Peptides composed of two amino acid units.
A naturally occurring dipeptide neuropeptide found in muscles.
EXOPEPTIDASES that specifically act on dipeptides. EC 3.4.13.
A NOD signaling adaptor protein that contains two C-terminal leucine-rich domains which recognize bacterial PEPTIDOGLYCAN. It signals via an N-terminal capase recruitment domain that interacts with other CARD SIGNALING ADAPTOR PROTEINS such as RIP SERINE-THEONINE KINASES. The protein plays a role in the host defense response by signaling the activation of CASPASES and the MAP KINASE SIGNALING SYSTEM. Mutations of the gene encoding the nucleotide oligomerization domain 2 protein have been associated with increased susceptibility to CROHN DISEASE.
The simplest of all peptides. It functions as a gamma-glutamyl acceptor.
Piperazines with two keto oxygens.
Membrane transporters that co-transport two or more dissimilar molecules in the same direction across a membrane. Usually the transport of one ion or molecule is against its electrochemical gradient and is "powered" by the movement of another ion or molecule with its electrochemical gradient.
Anserine is a muscle fiber protein, specifically a myosin heavy chain isoform, which is predominantly found in slow-twitch, type I muscle fibers and contributes to their contractile properties, playing a role in force production and fatigue resistance.
Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.
Peptides composed of between two and twelve amino acids.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
A non-essential amino acid. It is found primarily in gelatin and silk fibroin and used therapeutically as a nutrient. It is also a fast inhibitory neurotransmitter.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A papain-like cysteine protease that has specificity for amino terminal dipeptides. The enzyme plays a role in the activation of several pro-inflammatory serine proteases by removal of their aminoterminal inhibitory dipeptides. Genetic mutations that cause loss of cathepsin C activity in humans are associated with PAPILLON-LEFEVRE DISEASE.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
Long-acting, broad-spectrum, water-soluble, CEPHALEXIN derivative.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
A subclass of exopeptidases that includes enzymes which cleave either two or three AMINO ACIDS from the end of a peptide chain.
A semisynthetic cephalosporin antibiotic with antimicrobial activity similar to that of CEPHALORIDINE or CEPHALOTHIN, but somewhat less potent. It is effective against both gram-positive and gram-negative organisms.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by transamination. It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL NERVOUS SYSTEM.
The rate dynamics in chemical or physical systems.
The process of cleaving a chemical compound by the addition of a molecule of water.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
Ligases that catalyze the joining of adjacent AMINO ACIDS by the formation of carbon-nitrogen bonds between their carboxylic acid groups and amine groups.
Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (Freund's adjuvant, BCG, Corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
A subclass of EXOPEPTIDASES that act on the free N terminus end of a polypeptide liberating a single amino acid residue. EC 3.4.11.
Uptake of substances through the lining of the INTESTINES.
An essential branched-chain amino acid important for hemoglobin formation.
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A non-essential amino acid that is synthesized from GLUTAMIC ACID. It is an essential component of COLLAGEN and is important for proper functioning of joints and tendons.
Peptidoglycan is a complex, cross-linked polymer of carbohydrates and peptides that forms the rigid layer of the bacterial cell wall, providing structural support and protection while contributing to the bacterium's susceptibility or resistance to certain antibiotics.
Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).
The portion of the GASTROINTESTINAL TRACT between the PYLORUS of the STOMACH and the ILEOCECAL VALVE of the LARGE INTESTINE. It is divisible into three portions: the DUODENUM, the JEJUNUM, and the ILEUM.
A serine protease that catalyses the release of an N-terminal dipeptide. Several biologically-active peptides have been identified as dipeptidyl peptidase 4 substrates including INCRETINS; NEUROPEPTIDES; and CHEMOKINES. The protein is also found bound to ADENOSINE DEAMINASE on the T-CELL surface and is believed to play a role in T-cell activation.
A RIP serine-theonine kinase that contains a C-terminal caspase activation and recruitment domain. It can signal by associating with other CARD-signaling adaptor proteins and INITIATOR CASPASES that contain CARD domains within their N-terminal pro-domain region.
Toxic glycolipids composed of trehalose dimycolate derivatives. They are produced by MYCOBACTERIUM TUBERCULOSIS and other species of MYCOBACTERIUM. They induce cellular dysfunction in animals.
The middle portion of the SMALL INTESTINE, between DUODENUM and ILEUM. It represents about 2/5 of the remaining portion of the small intestine below duodenum.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.
An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.
An autosomal recessive disorder due to defective absorption of NEUTRAL AMINO ACIDS by both the intestine and the PROXIMAL RENAL TUBULES. The abnormal urinary loss of TRYPTOPHAN, a precursor of NIACIN, leads to a NICOTINAMIDE deficiency, PELLAGRA-like light-sensitive rash, CEREBELLAR ATAXIA, emotional instability, and aminoaciduria. Mutations involve the neurotransmitter transporter gene SLC6A19.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A zinc containing enzyme of the hydrolase class that catalyzes the removal of the N-terminal amino acid from most L-peptides, particularly those with N-terminal leucine residues but not those with N-terminal lysine or arginine residues. This occurs in tissue cell cytosol, with high activity in the duodenum, liver, and kidney. The activity of this enzyme is commonly assayed using a leucine arylamide chromogenic substrate such as leucyl beta-naphthylamide.
Transport proteins that carry specific substances in the blood or across cell membranes.

A novel role for carbonic anhydrase: cytoplasmic pH gradient dissipation in mouse small intestinal enterocytes. (1/2681)

1. The spatial and temporal distribution of intracellular H+ ions in response to activation of a proton-coupled dipeptide transporter localized at the apical pole of mouse small intestinal isolated enterocytes was investigated using intracellular carboxy-SNARF-1 fluorescence in combination with whole-cell microspectrofluorimetry or confocal microscopy. 2. In Hepes-buffered Tyrode solution, application of the dipeptide Phe-Ala (10 mM) to a single enterocyte reduced pHi locally in the apical submembranous space. After a short delay (8 s), a fall of pHi occurred more slowly at the basal pole. 3. In the presence of CO2/HCO3--buffered Tyrode solution, the apical and basal rates of acidification were not significantly different and the time delay was reduced to 1 s or less. 4. Following application of the carbonic anhydrase inhibitor acetazolamide (100 microM) in the presence of CO2/HCO3- buffer, addition of Phe-Ala once again produced a localized apical acidification that took 5 s to reach the basal pole. Basal acidification was slower than at the apical pole. 5. We conclude that acid influx due to proton-coupled dipeptide transport can lead to intracellular pH gradients and that intracellular carbonic anhydrase activity, by facilitating cytoplasmic H+ mobility, limits their magnitude and duration.  (+info)

Cluster of differentiation antigen 4 (CD4) endocytosis and adaptor complex binding require activation of the CD4 endocytosis signal by serine phosphorylation. (2/2681)

Cluster of differentiation antigen 4 (CD4), the T lymphocyte antigen receptor component and human immunodeficiency virus coreceptor, is down-modulated when cells are activated by antigen or phorbol esters. During down-modulation CD4 dissociates from p56(lck), undergoes endocytosis through clathrin-coated pits, and is then sorted in early endosomes to late endocytic organelles where it is degraded. Previous studies have suggested that phosphorylation and a dileucine sequence are required for down-modulation. Using transfected HeLa cells, in which CD4 endocytosis can be studied in the absence of p56(lck), we show that the dileucine sequence in the cytoplasmic domain is essential for clathrin-mediated CD4 endocytosis. However, this sequence is only functional as an endocytosis signal when neighboring serine residues are phosphorylated. Phosphoserine is required for rapid endocytosis because CD4 molecules in which the cytoplasmic domain serine residues are substituted with glutamic acid residues are not internalized efficiently. Using surface plasmon resonance, we show that CD4 peptides containing the dileucine sequence bind weakly to clathrin adaptor protein complexes 2 and 1. The affinity of this interaction is increased 350- to 700-fold when the peptides also contain phosphoserine residues.  (+info)

Caspase-dependent activation of calpain during drug-induced apoptosis. (3/2681)

We have previously demonstrated that calpain is responsible for the cleavage of Bax, a proapoptotic protein, during drug-induced apoptosis of HL-60 cells (Wood, D. E., Thomas, A., Devi, L. A., Berman, Y., Beavis, R. C., Reed, J. C., and Newcomb, E. W. (1998) Oncogene 17, 1069-1078). Here we show the sequential activation of caspases and calpain during drug-induced apoptosis of HL-60 cells. Time course experiments using the topoisomerase I inhibitor 9-amino-20(S)-camptothecin revealed that cleavage of caspase-3 substrates poly(ADP-ribose) polymerase (PARP) and the retinoblastoma protein as well as DNA fragmentation occurred several hours before calpain activation and Bax cleavage. Pretreatment with the calpain inhibitor calpeptin blocked calpain activation and Bax cleavage but did not inhibit PARP cleavage, DNA fragmentation, or 9-amino-20(S)-camptothecin-induced morphological changes and cell death. Pretreatment with the pan-caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-fmk) inhibited PARP cleavage, DNA fragmentation, calpain activation, and Bax cleavage and increased cell survival by 40%. Interestingly, Z-VAD-fmk-treated cells died in a caspase- and calpain-independent manner that appeared morphologically distinct from apoptosis. Our results suggest that excessive or uncontrolled calpain activity may play a role downstream of and distinct from caspases in the degradation phase of apoptosis.  (+info)

Posttranslational regulation of the retinoblastoma gene family member p107 by calpain protease. (4/2681)

The retinoblastoma protein plays a critical role in regulating the G1/S transition. Less is known about the function and regulation of the homologous pocket protein p107. Here we present evidence for the posttranslational regulation of p107 by the Ca2+-activated protease calpain. Three negative growth regulators, the HMG-CoA reductase inhibitor lovastatin, the antimetabolite 5-fluorouracil, and the cyclic nucleotide dibutyryl cAMP were found to induce cell type-specific loss of p107 protein which was reversible by the calpain inhibitor leucyl-leucyl-norleucinal but not by the serine protease inhibitor phenylmethylsulfonylfluoride, caspase inhibitors, or lactacystin, a specific inhibitor of the 26S proteasome. Purified calpain induced Ca2+-dependent p107 degradation in cell lysates. Transient expression of the specific calpain inhibitor calpastatin blocked the loss of p107 protein in lovastatin-treated cells, and the half-life of p107 was markedly lengthened in lovastatian-treated cells stably transfected with a calpastatin expression vector versus cells transfected with vector alone. The data presented here demonstrate down-regulation of p107 protein in response to various antiproliferative signals, and implicate calpain in p107 posttranslational regulation.  (+info)

Multiplicity of the H+-dependent transport mechanism of dipeptide and anionic beta-lactam antibiotic ceftibuten in rat intestinal brush-border membrane. (5/2681)

To elucidate the transport characteristics of the H+/dipeptide carrier that recognizes the orally active beta-lactam antibiotic ceftibuten, the uptake behaviors were compared of ceftibuten and Gly-Sar by rat intestinal brush-border membrane vesicles. The results show that 1) both the uptake of ceftibuten and that of Gly-Sar were dependent on an inwardly directed H+ gradient; 2) anionic compounds such as hippurylphenyllactic acid competitively inhibited ceftibuten uptake in the presence of H+ gradient, whereas this anion did not inhibit Gly-Sar uptake; and 3) the carrier-mediated uptake of ceftibuten did not disappear even in the presence of 20 mM Gly-Sar. The results provide an evidence that several transporters with different features are potentially responsible for the uptake of beta-lactam antibiotics into the intestinal cells. It is suggested that the dianionic beta-lactam antibiotics that carry a net negative charge such as ceftibuten use multiple H+-dependent transport systems for absorption.  (+info)

Interactions of a nonpeptidic drug, valacyclovir, with the human intestinal peptide transporter (hPEPT1) expressed in a mammalian cell line. (6/2681)

The results of previous work performed in our laboratory using an in situ perfusion technique in rats and rabbit apical brush border membrane vesicles have suggested that the intestinal uptake of valacyclovir (VACV) appears to be mediated by multiple membrane transporters. Using these techniques, it is difficult to characterize the transport kinetics of VACV with each individual transporter in the presence of multiple known or unknown transporters. The purpose of this study was to characterize the interaction of VACV and the human intestinal peptide transporter using Chinese hamster ovary (CHO) cells that overexpress the human intestinal peptide transporter (hPEPT1) gene. VACV uptake was significantly greater in CHO cells transfected with hPEPT1 than in cells transfected with only the vector, pcDNA3. The optimum pH for VACV uptake was determined to occur at pH 7.5. Proton cotransport was not observed in hPEPT1/CHO cells, consistent with previously observed results in tissues and Caco-2 cells. VACV uptake was concentration dependent and saturable with a Michaelis-Menten constant and maximum velocity of 1.64 +/- 0.06 mM and 23.34 +/- 0.36 nmol/mg protein/5 min, respectively. A very similar Km value was obtained in hPEPT1/CHO cells and in rat and rabbit tissues and Caco-2 cells, suggesting that hPEPT1 dominates the intestinal transport properties of VACV in vitro. VACV uptake was markedly inhibited by various dipeptides and beta-lactam antibiotics, and Ki values of 12.8 +/- 2.7 and 9.1 +/- 1.2 mM were obtained for Gly-Sar and cefadroxil at pH 7.5, respectively. The present results demonstrate that VACV is a substrate for the human intestinal peptide transporter in hPEPT1/CHO cells and that although transport is pH dependent, proton cotransport is not apparent. Also, the results demonstrate that the hPEPT1/CHO cell system has use in investigating the transport kinetics of drugs with the human intestinal peptide transporter hPEPT1; however, the extrapolation of these transport properties to the in vivo situation requires further investigation.  (+info)

Allosteric modulation of BPTI interaction with human alpha- and zeta-thrombin. (7/2681)

In this study, thrombin interaction with the basic pancreatic trypsin inhibitor (BPTI) was investigated in the presence of different allosteric modulators of thrombin, that is the C-terminal hirudin peptide 54-65 (Hir54-65), a recombinant thrombomodulin form (TMEGF4-6) and Na+. BPTI binding to alpha-thrombin is positively linked to Na+. Under low sodium concentration (5 mM Na+) the BPTI affinity for alpha-thrombin was roughly threefold lower than in the presence of 150 mM sodium (Ki = 320 microM vs. 100 microM). The hirudin fragment, which binds to the fibrinogen recognition site (FRS) of thrombin, induced a progressive and saturable decrease (3.6-fold) of alpha-thrombin affinity for BPTI, whereas the thrombomodulin peptide, which binds to a more extended region of FRS, caused a 5.5-fold increase of the enzyme affinity for the inhibitor. The opposite effect exerted by Hir54-65 and TMEGF4-6 was also observed for BPTI interaction with zeta-thrombin, in which the amidic bond between W148 and T149 is cleaved. However, in this case the effect by Hir54-65 and TMEGF4-6, although qualitatively similar to that observed with alpha-thrombin, had a smaller magnitude. Thrombin hydrolysis of Protein C was also differently affected by Hir54-65 and TMEGF4-6 peptides. While the latter enhanced the Protein C activation, the former caused a reduction of both alpha- and zeta-thrombin kcat/K(m)' for Protein C cleavage. These results showed that (a) Na+ facilitates BPTI interaction with thrombin; (b) Hir54-65 and TMEGF4-6, though sharing in part the same binding site at the thrombin FRS, can affect in opposite way thrombin's interaction with BPTI and Protein C; (c) such findings along with the results obtained with zeta-thrombin might be explained by admitting that the thermodynamic linkage between FRS and the critical W60-loop is also controlled by ligation and/or conformational state of the W148 insertion loop.  (+info)

Bifunctional inhibitors of the trypsin-like activity of eukaryotic proteasomes. (8/2681)

BACKGROUND: The 20S proteasome is a multicatalytic protease complex that exhibits trypsin-like, chymotrypsin-like and post-glutamyl-peptide hydrolytic activities associated with the active sites of the beta2, beta5 and beta1 subunits, respectively. Modulation of these activities using inhibitors is essential for a better understanding of the proteasome's mechanism of action. Although there are highly selective inhibitors of the proteasome's chymotryptic activity, inhibitors of similar specificity have not yet been identified for the other activities. RESULTS: The X-ray structure of the yeast proteasome reveals that the sidechain of Cys118 of the beta3 subunit protrudes into the S3 subsite of the beta2 active site. The location of this residue was exploited for the rational design of bidentated inhibitors containing a maleinimide moiety at the P3 position for covalent linkage to the thiol group and a carboxy-terminal aldehyde group for hemiacetal formation with the Thr1 hydroxyl group of the active site. Structure-based modelling was used to determine the optimal spacing of the maleinimide group from the P2-P1 dipeptide aldehydes and the specificity of the S1 subsite was exploited to limit the inhibitory activity to the beta2 active site. X-ray crystallographic analysis of a yeast proteasome-inhibitor adduct confirmed the expected irreversible binding of the inhibitor to the P3 subsite. CONCLUSIONS: Maleoyl-beta-alanyl-valyl-arginal is a new type of inhibitor that is highly selective for the trypsin-like activity of eukaryotic proteasomes. Despite the reactivity of the maleinimide group towards thiols, and therefore the limited use of this inhibitor for in vitro studies, it might represent an interesting new biochemical tool.  (+info)

A dipeptide is a type of molecule that is formed by the condensation of two amino acids. In this process, the carboxyl group (-COOH) of one amino acid combines with the amino group (-NH2) of another amino acid, releasing a water molecule and forming a peptide bond.

The resulting molecule contains two amino acids joined together by a single peptide bond, which is a type of covalent bond that forms between the carboxyl group of one amino acid and the amino group of another. Dipeptides are relatively simple molecules compared to larger polypeptides or proteins, which can contain hundreds or even thousands of amino acids linked together by multiple peptide bonds.

Dipeptides have a variety of biological functions in the body, including serving as building blocks for larger proteins and playing important roles in various physiological processes. Some dipeptides also have potential therapeutic uses, such as in the treatment of hypertension or muscle wasting disorders.

Carnosine is a dipeptide molecule composed of the amino acids histidine and alanine, which is naturally found in high concentrations in certain tissues of the body, particularly in muscle and brain tissue. It acts as an antioxidant, helping to protect cells from damage caused by free radicals and other oxidative stressors. Carnosine also has anti-glycation properties, meaning it helps prevent the formation of advanced glycation end products (AGEs) that can contribute to aging and age-related diseases. Additionally, carnosine has been shown to have potential benefits in neuroprotection, cardioprotection, and anti-inflammation. It is being studied for its potential therapeutic uses in various health conditions, including diabetes, cataracts, Alzheimer's disease, and other neurological disorders.

Dipeptidases are a group of enzymes that break down dipeptides, which are composed of two amino acids joined by a peptide bond. These enzymes catalyze the hydrolysis of dipeptides into individual amino acids, helping to facilitate their absorption and utilization in the body. Dipeptidases can be found on the brush border membrane of the small intestine, as well as in various tissues and organs, such as the kidneys, liver, and pancreas. They play a crucial role in protein metabolism and maintaining amino acid homeostasis within the body.

NOD2 (Nucleotide-binding Oligomerization Domain-containing protein 2) signaling adaptor protein, also known as CARD15 (Caspase Recruitment Domain-containing protein 15), is a crucial intracellular pattern recognition receptor (PRR) that plays an essential role in the innate immune response. NOD2 is primarily expressed in monocytes, macrophages, dendritic cells, and intestinal epithelial cells.

NOD2 signaling adaptor protein contains two caspase recruitment domains (CARD), a nucleotide-binding oligomerization domain (NOD), and multiple leucine-rich repeats (LRR). The LRR region is responsible for recognizing and binding to pathogen-associated molecular patterns (PAMPs) derived from bacterial cell walls, such as muramyl dipeptide (MDP). Upon recognition of MDP, NOD2 undergoes oligomerization through its NOD domain, which leads to the recruitment of receptor-interacting protein kinase 2 (RIPK2) via CARD-CARD interactions. This interaction results in the activation of downstream signaling pathways, including nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs), which ultimately induce the expression of proinflammatory cytokines, chemokines, and antimicrobial peptides.

Dysregulation or mutations in NOD2 signaling adaptor protein have been implicated in several inflammatory diseases, such as Crohn's disease, Blau syndrome, and susceptibility to certain mycobacterial infections.

Glycylglycine is not a medical condition or term, but rather it is a chemical compound. It is a dipeptide, which means it is composed of two amino acids linked together. Specifically, glycylglycine consists of two glycine molecules joined by an amide bond (also known as a peptide bond) between the carboxyl group of one glycine and the amino group of the other glycine.

Glycylglycine is often used in laboratory research as a buffer, a substance that helps maintain a stable pH level in a solution. It has a relatively simple structure and is not naturally found in significant amounts in living organisms.

Diketopiperazines are a type of cyclic compound that contains two adjacent amide bonds. They are formed by the condensation of two α-amino acids, resulting in a five-membered ring structure. Diketopiperazines can be found naturally in various organisms and are also produced synthetically for use in pharmaceuticals and other applications.

In medical terms, diketopiperazines have been studied for their potential therapeutic uses. Some diketopiperazines have been found to have anti-inflammatory, antimicrobial, and anticancer properties. For example, the diketopiperazine cyclo(L-tryptophanyl-L-prolyl) has been shown to have anti-inflammatory effects by inhibiting the production of pro-inflammatory cytokines. Additionally, some diketopiperazines have been found to have anticancer activity by inducing apoptosis (programmed cell death) in cancer cells.

However, it is important to note that while some diketopiperazines have shown promise as potential therapeutic agents, more research is needed to fully understand their mechanisms of action and safety profiles before they can be used clinically.

A symporter is a type of transmembrane protein that functions to transport two or more molecules or ions across a biological membrane in the same direction, simultaneously. This process is called co-transport and it is driven by the concentration gradient of one of the substrates, which is usually an ion such as sodium (Na+) or proton (H+).

Symporters are classified based on the type of energy that drives the transport process. Primary active transporters, such as symporters, use the energy from ATP hydrolysis or from the electrochemical gradient of ions to move substrates against their concentration gradient. In contrast, secondary active transporters use the energy stored in an existing electrochemical gradient of one substrate to drive the transport of another substrate against its own concentration gradient.

Symporters play important roles in various physiological processes, including nutrient uptake, neurotransmitter reuptake, and ion homeostasis. For example, the sodium-glucose transporter (SGLT) is a symporter that co-transports glucose and sodium ions across the intestinal epithelium and the renal proximal tubule, contributing to glucose absorption and regulation of blood glucose levels. Similarly, the dopamine transporter (DAT) is a symporter that co-transports dopamine and sodium ions back into presynaptic neurons, terminating the action of dopamine in the synapse.

Anserine is a type of protein that belongs to the family of muscle proteins called myofibrillar proteins. It is found in high concentrations in the muscles of birds, especially in the breast muscle, and is also present in the muscles of some mammals, including humans. Anserine is composed of three peptide chains: two actin molecules and one tropomyosin molecule. It plays a role in the contraction and relaxation of muscles, and has been studied for its potential role in muscle function and disease. In humans, anserine is found primarily in type II (fast-twitch) muscle fibers, which are responsible for powerful, quick movements.

Glycopeptides are a class of antibiotics that are characterized by their complex chemical structure, which includes both peptide and carbohydrate components. These antibiotics are produced naturally by certain types of bacteria and are effective against a range of Gram-positive bacterial infections, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE).

The glycopeptide antibiotics work by binding to the bacterial cell wall precursor, preventing the cross-linking of peptidoglycan chains that is necessary for the formation of a strong and rigid cell wall. This leads to the death of the bacteria.

Examples of glycopeptides include vancomycin, teicoplanin, and dalbavancin. While these antibiotics have been used successfully for many years, their use is often limited due to concerns about the emergence of resistance and potential toxicity.

Oligopeptides are defined in medicine and biochemistry as short chains of amino acids, typically containing fewer than 20 amino acid residues. These small peptides are important components in various biological processes, such as serving as signaling molecules, enzyme inhibitors, or structural elements in some proteins. They can be found naturally in foods and may also be synthesized for use in medical research and therapeutic applications.

Amino acids are organic compounds that serve as the building blocks of proteins. They consist of a central carbon atom, also known as the alpha carbon, which is bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain (R group). The R group can be composed of various combinations of atoms such as hydrogen, oxygen, sulfur, nitrogen, and carbon, which determine the unique properties of each amino acid.

There are 20 standard amino acids that are encoded by the genetic code and incorporated into proteins during translation. These include:

1. Alanine (Ala)
2. Arginine (Arg)
3. Asparagine (Asn)
4. Aspartic acid (Asp)
5. Cysteine (Cys)
6. Glutamine (Gln)
7. Glutamic acid (Glu)
8. Glycine (Gly)
9. Histidine (His)
10. Isoleucine (Ile)
11. Leucine (Leu)
12. Lysine (Lys)
13. Methionine (Met)
14. Phenylalanine (Phe)
15. Proline (Pro)
16. Serine (Ser)
17. Threonine (Thr)
18. Tryptophan (Trp)
19. Tyrosine (Tyr)
20. Valine (Val)

Additionally, there are several non-standard or modified amino acids that can be incorporated into proteins through post-translational modifications, such as hydroxylation, methylation, and phosphorylation. These modifications expand the functional diversity of proteins and play crucial roles in various cellular processes.

Amino acids are essential for numerous biological functions, including protein synthesis, enzyme catalysis, neurotransmitter production, energy metabolism, and immune response regulation. Some amino acids can be synthesized by the human body (non-essential), while others must be obtained through dietary sources (essential).

Glycine is a simple amino acid that plays a crucial role in the body. According to the medical definition, glycine is an essential component for the synthesis of proteins, peptides, and other biologically important compounds. It is also involved in various metabolic processes, such as the production of creatine, which supports muscle function, and the regulation of neurotransmitters, affecting nerve impulse transmission and brain function. Glycine can be found as a free form in the body and is also present in many dietary proteins.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Cathepsin C is a lysosomal cysteine protease that plays a role in intracellular protein degradation and activation of other proteases. It is also known as dipeptidyl peptidase I (DPP I) because of its ability to remove dipeptides from the N-terminus of polypeptides. Cathepsin C is widely expressed in many tissues, including immune cells, and has been implicated in various physiological and pathological processes such as antigen presentation, bone resorption, and tumor cell invasion. Defects in the gene encoding cathepsin C have been associated with several genetic disorders, including Papillon-Lefèvre syndrome and Haim-Munk syndrome, which are characterized by severe periodontal disease and skin abnormalities.

Substrate specificity in the context of medical biochemistry and enzymology refers to the ability of an enzyme to selectively bind and catalyze a chemical reaction with a particular substrate (or a group of similar substrates) while discriminating against other molecules that are not substrates. This specificity arises from the three-dimensional structure of the enzyme, which has evolved to match the shape, charge distribution, and functional groups of its physiological substrate(s).

Substrate specificity is a fundamental property of enzymes that enables them to carry out highly selective chemical transformations in the complex cellular environment. The active site of an enzyme, where the catalysis takes place, has a unique conformation that complements the shape and charge distribution of its substrate(s). This ensures efficient recognition, binding, and conversion of the substrate into the desired product while minimizing unwanted side reactions with other molecules.

Substrate specificity can be categorized as:

1. Absolute specificity: An enzyme that can only act on a single substrate or a very narrow group of structurally related substrates, showing no activity towards any other molecule.
2. Group specificity: An enzyme that prefers to act on a particular functional group or class of compounds but can still accommodate minor structural variations within the substrate.
3. Broad or promiscuous specificity: An enzyme that can act on a wide range of structurally diverse substrates, albeit with varying catalytic efficiencies.

Understanding substrate specificity is crucial for elucidating enzymatic mechanisms, designing drugs that target specific enzymes or pathways, and developing biotechnological applications that rely on the controlled manipulation of enzyme activities.

Cefadroxil is a type of antibiotic known as a cephalosporin. It works by interfering with the bacteria's ability to form a cell wall, which is necessary for its survival. Without a functional cell wall, the bacteria eventually die. Cefadroxil is used to treat a variety of infections caused by bacteria, including skin infections, ear infections, and urinary tract infections.

Cefadroxil is available as a prescription medication and is typically taken by mouth in the form of a tablet or liquid suspension. It is usually taken one to two times a day, depending on the severity of the infection and the individual patient's needs.

As with all antibiotics, it is important to take cefadroxil exactly as directed by your healthcare provider and to finish the entire course of treatment, even if you start to feel better. This will help ensure that the infection is fully treated and reduce the risk of the bacteria becoming resistant to the antibiotic.

Some common side effects of cefadroxil include nausea, vomiting, diarrhea, and stomach pain. In rare cases, more serious side effects may occur, such as an allergic reaction or severe skin reactions. If you experience any unusual symptoms while taking cefadroxil, it is important to contact your healthcare provider right away.

Peptides are short chains of amino acid residues linked by covalent bonds, known as peptide bonds. They are formed when two or more amino acids are joined together through a condensation reaction, which results in the elimination of a water molecule and the formation of an amide bond between the carboxyl group of one amino acid and the amino group of another.

Peptides can vary in length from two to about fifty amino acids, and they are often classified based on their size. For example, dipeptides contain two amino acids, tripeptides contain three, and so on. Oligopeptides typically contain up to ten amino acids, while polypeptides can contain dozens or even hundreds of amino acids.

Peptides play many important roles in the body, including serving as hormones, neurotransmitters, enzymes, and antibiotics. They are also used in medical research and therapeutic applications, such as drug delivery and tissue engineering.

Dipeptidyl-peptidases (DPPs) and tripeptidyl-peptidases (TPPs) are two types of enzymes that belong to the class of peptidases, which are proteins that help break down other proteins into smaller peptides or individual amino acids.

Dipeptidyl-peptidases cleave dipeptides (two-amino acid units) from the N-terminus (the end with a free amino group) of polypeptides and proteins, while tripeptidyl-peptidases cleave tripeptides (three-amino acid units) from the same location.

There are several different isoforms of DPPs and TPPs that have been identified in various organisms, including humans. These enzymes play important roles in regulating various physiological processes, such as digestion, immune function, and blood glucose homeostasis.

Inhibitors of DPP-4, one specific isoform of DPPs, have been developed for the treatment of type 2 diabetes, as they help increase the levels of incretin hormones that stimulate insulin secretion and suppress glucagon production.

Cephalexin is a type of antibiotic known as a first-generation cephalosporin. It works by interfering with the bacteria's ability to form a cell wall, which is essential for its survival. Without a functional cell wall, the bacterial cells become unstable and eventually die.

Cephalexin is effective against a wide range of gram-positive and some gram-negative bacteria, making it a useful antibiotic for treating various types of infections, such as respiratory tract infections, skin and soft tissue infections, bone and joint infections, and urinary tract infections.

Like all antibiotics, cephalexin should be used only to treat bacterial infections, as it has no effect on viral infections. It is important to take the full course of treatment as directed by a healthcare professional, even if symptoms improve before the medication is finished, to ensure that the infection is fully treated and to reduce the risk of antibiotic resistance.

Common side effects of cephalexin include nausea, diarrhea, vomiting, and stomach pain. In rare cases, more serious side effects such as allergic reactions, severe skin rashes, or liver damage may occur. It is important to seek medical attention immediately if any signs of an allergic reaction or serious side effect are experienced while taking cephalexin.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Alanine is an alpha-amino acid that is used in the biosynthesis of proteins. The molecular formula for alanine is C3H7NO2. It is a non-essential amino acid, which means that it can be produced by the human body through the conversion of other nutrients, such as pyruvate, and does not need to be obtained directly from the diet.

Alanine is classified as an aliphatic amino acid because it contains a simple carbon side chain. It is also a non-polar amino acid, which means that it is hydrophobic and tends to repel water. Alanine plays a role in the metabolism of glucose and helps to regulate blood sugar levels. It is also involved in the transfer of nitrogen between tissues and helps to maintain the balance of nitrogen in the body.

In addition to its role as a building block of proteins, alanine is also used as a neurotransmitter in the brain and has been shown to have a calming effect on the nervous system. It is found in many foods, including meats, poultry, fish, eggs, dairy products, and legumes.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Hydrolysis is a chemical process, not a medical one. However, it is relevant to medicine and biology.

Hydrolysis is the breakdown of a chemical compound due to its reaction with water, often resulting in the formation of two or more simpler compounds. In the context of physiology and medicine, hydrolysis is a crucial process in various biological reactions, such as the digestion of food molecules like proteins, carbohydrates, and fats. Enzymes called hydrolases catalyze these hydrolysis reactions to speed up the breakdown process in the body.

Biological transport refers to the movement of molecules, ions, or solutes across biological membranes or through cells in living organisms. This process is essential for maintaining homeostasis, regulating cellular functions, and enabling communication between cells. There are two main types of biological transport: passive transport and active transport.

Passive transport does not require the input of energy and includes:

1. Diffusion: The random movement of molecules from an area of high concentration to an area of low concentration until equilibrium is reached.
2. Osmosis: The diffusion of solvent molecules (usually water) across a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.
3. Facilitated diffusion: The assisted passage of polar or charged substances through protein channels or carriers in the cell membrane, which increases the rate of diffusion without consuming energy.

Active transport requires the input of energy (in the form of ATP) and includes:

1. Primary active transport: The direct use of ATP to move molecules against their concentration gradient, often driven by specific transport proteins called pumps.
2. Secondary active transport: The coupling of the movement of one substance down its electrochemical gradient with the uphill transport of another substance, mediated by a shared transport protein. This process is also known as co-transport or counter-transport.

Peptide synthases are a group of enzymes that catalyze the formation of peptide bonds between specific amino acids to produce peptides or proteins. They are responsible for the biosynthesis of many natural products, including antibiotics, bacterial toxins, and immunomodulatory peptides.

Peptide synthases are large, complex enzymes that consist of multiple domains and modules, each of which is responsible for activating and condensing specific amino acids. The activation of amino acids involves the formation of an aminoacyl-adenylate intermediate, followed by transfer of the activated amino acid to a thiol group on the enzyme. The condensation of two activated amino acids results in the formation of a peptide bond and release of adenosine monophosphate (AMP) and pyrophosphate.

Peptide synthases are found in all three domains of life, but are most commonly associated with bacteria and fungi. They play important roles in the biosynthesis of many natural products that have therapeutic potential, making them targets for drug discovery and development.

Immunologic adjuvants are substances that are added to a vaccine to enhance the body's immune response to the antigens contained in the vaccine. They work by stimulating the immune system and promoting the production of antibodies and activating immune cells, such as T-cells and macrophages, which help to provide a stronger and more sustained immune response to the vaccine.

Immunologic adjuvants can be derived from various sources, including bacteria, viruses, and chemicals. Some common examples include aluminum salts (alum), oil-in-water emulsions (such as MF59), and bacterial components (such as lipopolysaccharide or LPS).

The use of immunologic adjuvants in vaccines can help to improve the efficacy of the vaccine, particularly for vaccines that contain weak or poorly immunogenic antigens. They can also help to reduce the amount of antigen needed in a vaccine, which can be beneficial for vaccines that are difficult or expensive to produce.

It's important to note that while adjuvants can enhance the immune response to a vaccine, they can also increase the risk of adverse reactions, such as inflammation and pain at the injection site. Therefore, the use of immunologic adjuvants must be carefully balanced against their potential benefits and risks.

A Structure-Activity Relationship (SAR) in the context of medicinal chemistry and pharmacology refers to the relationship between the chemical structure of a drug or molecule and its biological activity or effect on a target protein, cell, or organism. SAR studies aim to identify patterns and correlations between structural features of a compound and its ability to interact with a specific biological target, leading to a desired therapeutic response or undesired side effects.

By analyzing the SAR, researchers can optimize the chemical structure of lead compounds to enhance their potency, selectivity, safety, and pharmacokinetic properties, ultimately guiding the design and development of novel drugs with improved efficacy and reduced toxicity.

Aminopeptidases are a group of enzymes that catalyze the removal of amino acids from the N-terminus of polypeptides and proteins. They play important roles in various biological processes, including protein degradation, processing, and activation. Aminopeptidases are classified based on their specificity for different types of amino acids and the mechanism of their action. Some of the well-known aminopeptidases include leucine aminopeptidase, alanyl aminopeptidase, and arginine aminopeptidase. They are widely distributed in nature and found in various tissues and organisms, including bacteria, plants, and animals. In humans, aminopeptidases are involved in several physiological functions, such as digestion, immune response, and blood pressure regulation.

Intestinal absorption refers to the process by which the small intestine absorbs water, nutrients, and electrolytes from food into the bloodstream. This is a critical part of the digestive process, allowing the body to utilize the nutrients it needs and eliminate waste products. The inner wall of the small intestine contains tiny finger-like projections called villi, which increase the surface area for absorption. Nutrients are absorbed into the bloodstream through the walls of the capillaries in these villi, and then transported to other parts of the body for use or storage.

Leucine is an essential amino acid, meaning it cannot be produced by the human body and must be obtained through the diet. It is one of the three branched-chain amino acids (BCAAs), along with isoleucine and valine. Leucine is critical for protein synthesis and muscle growth, and it helps to regulate blood sugar levels, promote wound healing, and produce growth hormones.

Leucine is found in various food sources such as meat, dairy products, eggs, and certain plant-based proteins like soy and beans. It is also available as a dietary supplement for those looking to increase their intake for athletic performance or muscle recovery purposes. However, it's important to consult with a healthcare professional before starting any new supplement regimen.

Stereoisomerism is a type of isomerism (structural arrangement of atoms) in which molecules have the same molecular formula and sequence of bonded atoms, but differ in the three-dimensional orientation of their atoms in space. This occurs when the molecule contains asymmetric carbon atoms or other rigid structures that prevent free rotation, leading to distinct spatial arrangements of groups of atoms around a central point. Stereoisomers can have different chemical and physical properties, such as optical activity, boiling points, and reactivities, due to differences in their shape and the way they interact with other molecules.

There are two main types of stereoisomerism: enantiomers (mirror-image isomers) and diastereomers (non-mirror-image isomers). Enantiomers are pairs of stereoisomers that are mirror images of each other, but cannot be superimposed on one another. Diastereomers, on the other hand, are non-mirror-image stereoisomers that have different physical and chemical properties.

Stereoisomerism is an important concept in chemistry and biology, as it can affect the biological activity of molecules, such as drugs and natural products. For example, some enantiomers of a drug may be active, while others are inactive or even toxic. Therefore, understanding stereoisomerism is crucial for designing and synthesizing effective and safe drugs.

Hydrogen-ion concentration, also known as pH, is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm (to the base 10) of the hydrogen ion activity in a solution. The standard unit of measurement is the pH unit. A pH of 7 is neutral, less than 7 is acidic, and greater than 7 is basic.

In medical terms, hydrogen-ion concentration is important for maintaining homeostasis within the body. For example, in the stomach, a high hydrogen-ion concentration (low pH) is necessary for the digestion of food. However, in other parts of the body such as blood, a high hydrogen-ion concentration can be harmful and lead to acidosis. Conversely, a low hydrogen-ion concentration (high pH) in the blood can lead to alkalosis. Both acidosis and alkalosis can have serious consequences on various organ systems if not corrected.

Proline is an organic compound that is classified as a non-essential amino acid, meaning it can be produced by the human body and does not need to be obtained through the diet. It is encoded in the genetic code as the codon CCU, CCC, CCA, or CCG. Proline is a cyclic amino acid, containing an unusual secondary amine group, which forms a ring structure with its carboxyl group.

In proteins, proline acts as a structural helix breaker, disrupting the alpha-helix structure and leading to the formation of turns and bends in the protein chain. This property is important for the proper folding and function of many proteins. Proline also plays a role in the stability of collagen, a major structural protein found in connective tissues such as tendons, ligaments, and skin.

In addition to its role in protein structure, proline has been implicated in various cellular processes, including signal transduction, apoptosis, and oxidative stress response. It is also a precursor for the synthesis of other biologically important compounds such as hydroxyproline, which is found in collagen and elastin, and glutamate, an excitatory neurotransmitter in the brain.

Peptidoglycan is a complex biological polymer made up of sugars and amino acids that forms a crucial component of the cell walls of bacteria. It provides structural support and protection to bacterial cells, contributing to their shape and rigidity. Peptidoglycan is unique to bacterial cell walls and is not found in the cells of other organisms, such as plants, animals, or fungi.

The polymer is composed of linear chains of alternating units of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM), which are linked together by glycosidic bonds. The NAM residues contain short peptide side chains, typically consisting of four amino acids, that cross-link adjacent polysaccharide chains, forming a rigid layer around the bacterial cell.

The composition and structure of peptidoglycan can vary between different species of bacteria, which is one factor contributing to their diversity. The enzymes responsible for synthesizing and degrading peptidoglycan are important targets for antibiotics, as inhibiting these processes can weaken or kill the bacterial cells without affecting host organisms.

Cyclic peptides are a type of peptides in which the N-terminus and C-terminus of the peptide chain are linked to form a circular structure. This is in contrast to linear peptides, which have a straight peptide backbone with a free N-terminus and C-terminus. The cyclization of peptides can occur through various mechanisms, including the formation of an amide bond between the N-terminal amino group and the C-terminal carboxylic acid group (head-to-tail cyclization), or through the formation of a bond between side chain functional groups.

Cyclic peptides have unique structural and chemical properties that make them valuable in medical and therapeutic applications. For example, they are more resistant to degradation by enzymes compared to linear peptides, which can increase their stability and half-life in the body. Additionally, the cyclic structure allows for greater conformational rigidity, which can enhance their binding affinity and specificity to target molecules.

Cyclic peptides have been explored as potential therapeutics for a variety of diseases, including cancer, infectious diseases, and neurological disorders. They have also been used as tools in basic research to study protein-protein interactions and cell signaling pathways.

The small intestine is the portion of the gastrointestinal tract that extends from the pylorus of the stomach to the beginning of the large intestine (cecum). It plays a crucial role in the digestion and absorption of nutrients from food. The small intestine is divided into three parts: the duodenum, jejunum, and ileum.

1. Duodenum: This is the shortest and widest part of the small intestine, approximately 10 inches long. It receives chyme (partially digested food) from the stomach and begins the process of further digestion with the help of various enzymes and bile from the liver and pancreas.
2. Jejunum: The jejunum is the middle section, which measures about 8 feet in length. It has a large surface area due to the presence of circular folds (plicae circulares), finger-like projections called villi, and microvilli on the surface of the absorptive cells (enterocytes). These structures increase the intestinal surface area for efficient absorption of nutrients, electrolytes, and water.
3. Ileum: The ileum is the longest and final section of the small intestine, spanning about 12 feet. It continues the absorption process, mainly of vitamin B12, bile salts, and any remaining nutrients. At the end of the ileum, there is a valve called the ileocecal valve that prevents backflow of contents from the large intestine into the small intestine.

The primary function of the small intestine is to absorb the majority of nutrients, electrolytes, and water from ingested food. The mucosal lining of the small intestine contains numerous goblet cells that secrete mucus, which protects the epithelial surface and facilitates the movement of chyme through peristalsis. Additionally, the small intestine hosts a diverse community of microbiota, which contributes to various physiological functions, including digestion, immunity, and protection against pathogens.

Dipeptidyl peptidase 4 (DPP-4) is a serine protease enzyme that is widely distributed in various tissues and organs, including the kidney, liver, intestines, and immune cells. It plays a crucial role in regulating several biological processes, such as glucose metabolism, immune function, and cell signaling.

In terms of glucose metabolism, DPP-4 is responsible for breaking down incretin hormones, including glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), which are released from the gut in response to food intake. These hormones stimulate insulin secretion from pancreatic beta cells, suppress glucagon release, and promote satiety, thereby helping to regulate blood sugar levels. By degrading GLP-1 and GIP, DPP-4 reduces their activity and contributes to the development of type 2 diabetes.

DPP-4 inhibitors are a class of drugs used to treat type 2 diabetes by blocking the action of DPP-4 and increasing incretin hormone levels, leading to improved insulin secretion and glucose control.

Receptor-Interacting Protein Serine-Threonine Kinase 2 (RIPK2) is a protein that plays a crucial role in the regulation of inflammatory and cell death pathways. It is a serine-threonine kinase that interacts with receptors involved in innate immune signaling, such as TNFR1 and TLRs. RIPK2 is essential for the activation of NF-κB, a transcription factor that regulates the expression of genes involved in inflammation, immunity, and cell survival. Additionally, RIPK2 has been implicated in the regulation of programmed cell death pathways such as necroptosis. Mutations in RIPK2 have been associated with various immune-related disorders, including inflammatory bowel disease and Blau syndrome.

Cord factors are a group of glycolipids that are found on the surface of mycobacteria, including Mycobacterium tuberculosis, which is the bacterium that causes tuberculosis. These cord factors are called "cord factors" because they help to form characteristic "cords" or cable-like structures when mycobacteria grow in clumps.

Cord factors contribute to the virulence of mycobacteria by inhibiting the ability of certain immune cells, such as macrophages, to destroy the bacteria. They do this by preventing the fusion of lysosomes (which contain enzymes that can break down and kill the bacteria) with phagosomes (the compartments in which the bacteria are contained within the macrophage). This allows the mycobacteria to survive and replicate inside the host cells, leading to the development of tuberculosis.

Cord factors have also been shown to induce the production of pro-inflammatory cytokines, which can contribute to tissue damage and the pathogenesis of tuberculosis. Therefore, cord factors are an important target for the development of new therapies and vaccines against tuberculosis.

The jejunum is the middle section of the small intestine, located between the duodenum and the ileum. It is responsible for the majority of nutrient absorption that occurs in the small intestine, particularly carbohydrates, proteins, and some fats. The jejunum is characterized by its smooth muscle structure, which allows it to contract and mix food with digestive enzymes and absorb nutrients through its extensive network of finger-like projections called villi.

The jejunum is also lined with microvilli, which further increase the surface area available for absorption. Additionally, the jejunum contains numerous lymphatic vessels called lacteals, which help to absorb fats and fat-soluble vitamins into the bloodstream. Overall, the jejunum plays a critical role in the digestion and absorption of nutrients from food.

'Escherichia coli' (E. coli) is a type of gram-negative, facultatively anaerobic, rod-shaped bacterium that commonly inhabits the intestinal tract of humans and warm-blooded animals. It is a member of the family Enterobacteriaceae and one of the most well-studied prokaryotic model organisms in molecular biology.

While most E. coli strains are harmless and even beneficial to their hosts, some serotypes can cause various forms of gastrointestinal and extraintestinal illnesses in humans and animals. These pathogenic strains possess virulence factors that enable them to colonize and damage host tissues, leading to diseases such as diarrhea, urinary tract infections, pneumonia, and sepsis.

E. coli is a versatile organism with remarkable genetic diversity, which allows it to adapt to various environmental niches. It can be found in water, soil, food, and various man-made environments, making it an essential indicator of fecal contamination and a common cause of foodborne illnesses. The study of E. coli has contributed significantly to our understanding of fundamental biological processes, including DNA replication, gene regulation, and protein synthesis.

Membrane transport proteins are specialized biological molecules, specifically integral membrane proteins, that facilitate the movement of various substances across the lipid bilayer of cell membranes. They are responsible for the selective and regulated transport of ions, sugars, amino acids, nucleotides, and other molecules into and out of cells, as well as within different cellular compartments. These proteins can be categorized into two main types: channels and carriers (or pumps). Channels provide a passive transport mechanism, allowing ions or small molecules to move down their electrochemical gradient, while carriers actively transport substances against their concentration gradient, requiring energy usually in the form of ATP. Membrane transport proteins play a crucial role in maintaining cell homeostasis, signaling processes, and many other physiological functions.

Phenylalanine is an essential amino acid, meaning it cannot be produced by the human body and must be obtained through diet or supplementation. It's one of the building blocks of proteins and is necessary for the production of various molecules in the body, such as neurotransmitters (chemical messengers in the brain).

Phenylalanine has two forms: L-phenylalanine and D-phenylalanine. L-phenylalanine is the form found in proteins and is used by the body for protein synthesis, while D-phenylalanine has limited use in humans and is not involved in protein synthesis.

Individuals with a rare genetic disorder called phenylketonuria (PKU) must follow a low-phenylalanine diet or take special medical foods because they are unable to metabolize phenylalanine properly, leading to its buildup in the body and potential neurological damage.

Hartnup disease is a rare autosomal recessive disorder of amino acid transport, characterized by the excretion of large amounts of neutral amino acids in the urine and pellagra-like symptoms. It is caused by mutations in the SLC6A19 gene, which encodes for the B0AT1 protein, a neutral amino acid transporter in the brush border of the small intestine and kidney proximal tubule. The disease affects the absorption and reabsorption of neutral amino acids, leading to their deficiency in the body. Symptoms can include skin rashes, cerebellar ataxia, psychiatric symptoms, and episodic neurological symptoms that respond to treatment with nicotinamide (a form of vitamin B3). The diagnosis is confirmed by detecting increased excretion of neutral amino acids in the urine. Treatment typically involves dietary supplementation with affected amino acids and nicotinamide.

Molecular models are three-dimensional representations of molecular structures that are used in the field of molecular biology and chemistry to visualize and understand the spatial arrangement of atoms and bonds within a molecule. These models can be physical or computer-generated and allow researchers to study the shape, size, and behavior of molecules, which is crucial for understanding their function and interactions with other molecules.

Physical molecular models are often made up of balls (representing atoms) connected by rods or sticks (representing bonds). These models can be constructed manually using materials such as plastic or wooden balls and rods, or they can be created using 3D printing technology.

Computer-generated molecular models, on the other hand, are created using specialized software that allows researchers to visualize and manipulate molecular structures in three dimensions. These models can be used to simulate molecular interactions, predict molecular behavior, and design new drugs or chemicals with specific properties. Overall, molecular models play a critical role in advancing our understanding of molecular structures and their functions.

Leucyl aminopeptidase (LAP) is an enzyme that plays a role in the metabolism and breakdown of proteins. It is found in various tissues and organs throughout the body, including the small intestine, liver, and kidneys. LAP specifically catalyzes the removal of leucine, a type of amino acid, from the N-terminus (the beginning) of peptides and proteins. This enzyme is important for the proper digestion and absorption of dietary proteins, as well as for the regulation of various physiological processes in the body. Abnormal levels or activity of LAP have been implicated in certain diseases, such as cancer and liver disease.

Carrier proteins, also known as transport proteins, are a type of protein that facilitates the movement of molecules across cell membranes. They are responsible for the selective and active transport of ions, sugars, amino acids, and other molecules from one side of the membrane to the other, against their concentration gradient. This process requires energy, usually in the form of ATP (adenosine triphosphate).

Carrier proteins have a specific binding site for the molecule they transport, and undergo conformational changes upon binding, which allows them to move the molecule across the membrane. Once the molecule has been transported, the carrier protein returns to its original conformation, ready to bind and transport another molecule.

Carrier proteins play a crucial role in maintaining the balance of ions and other molecules inside and outside of cells, and are essential for many physiological processes, including nerve impulse transmission, muscle contraction, and nutrient uptake.

For example, the dipeptide Ala-Gln has the solubility of 586 g/L more than 10x the solubility of Gln (35 g/L). Dipeptides also ... A well known dipeptide is aspartame, an artificial sweetener. Dipeptides are white solids. Many are far more water-soluble than ... Dipeptides activate G-cells found in the stomach to secrete gastrin. Diketopiperazines are a special class of dipeptides, which ... Dietary proteins are digested to dipeptides and amino acids, and the dipeptides are absorbed more rapidly than the amino acids ...
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... is constituent of both Gram-positive and Gram-negative bacteria composed of N-acetylmuramic acid linked by ... Dipeptide Mifamurtide, a synthetic analogue for the treatment of osteosarcoma Inohara, N.; Ogura, Y.; Fontalba, A.; Gutierrez, ... 2004 Nov 9;14(21):1929-34., Martinon F, Agostini L, Meylan E, Tschopp J. Identification of bacterial muramyl dipeptide as ... "Host Recognition of Bacterial Muramyl Dipeptide Mediated through NOD2. Implications for Crohn's Disease". Journal of Biological ...
Dipeptides with an ester terminus spontaneously cyclize often. Racemization can be problematic. The Ugi reaction using an ... These cyclic dipeptides incorporate both donor and acceptor groups for hydrogen bonding. They are conformationally constrained ... Most commonly 2,5-diketopiperazines are generated by cyclisation of dipeptides. In addition to the many methods of peptide ... Ilaria, Belleza (2014). "Cyclic dipeptides: from bugs to brain". Trends in Molecular Medicine. 20: 551-8. Tullberg M, Grøtli M ...
It is a dipeptide consisting of alanine and glutamine. As a dietary supplement, alanyl-glutamine protects the gastrointestinal ... In cell culture, L-alanyl-L-glutamine is sometimes used as a replacement for L-glutamine because this dipeptide is stable in ... Fürst, Peter; Pogan, Karin; Stehle, Peter (1997). "Glutamine dipeptides in clinical nutrition". Nutrition. 13 (7-8): 731-737. ... Effects of parenteral nutrition with or without alanyl-glutamine dipeptide supplementation". Nutrition. 24 (1): 37-44. doi: ...
Xue, Jinghua; Wu, Min (27 March 2015). "Cyclic Dipeptides from Streptomyces michiganensis". Chemistry of Natural Compounds. 51 ...
Trusek-Holownia A. (2003). "Synthesis of ZAlaPheOMe, the precursor of bitter dipeptide in the two-phase ethyl acetate-water ... Yagasaki, Makoto; Hashimoto, Shin-ichi (November 2008). "Synthesis and application of dipeptides; current status and ...
This is found with dipeptides. The reagent is commonly used in the biuret protein assay, a colorimetric test used to determine ... Datta, S. P.; Leberman, R.; Rabin, B. R. (1959). "The chelation of metal ions by dipeptides and related substances. Part 5.- ...
... is a methyl ester of the dipeptide of the natural amino acids L-aspartic acid and L-phenylalanine. Under strongly ... It is a methyl ester of the aspartic acid/phenylalanine dipeptide with brand names NutraSweet, Equal, and Canderel. Aspartame ... Yagasaki M, Hashimoto S (November 2008). "Synthesis and application of dipeptides; current status and perspectives". Applied ... Dipeptides, Carboxylate esters, Sugar substitutes, Methyl esters, E-number additives). ...
Blumberg S, Tauber Z (October 1983). "Inhibition of metalloendopeptidases by 2-mercaptoacetyl-dipeptides". European Journal of ...
At the low end are the dipeptides. The most important drugs with a dipeptide (L-alanyl-L-proline) moiety are the "-pril" ... is a dipeptide. At the high end there is the anticoagulant hirudin, MW ≈ 7000, which is composed of 65 amino acids. Apart from ...
Nanotubes formed from dipeptides are the widest among peptide nanotubes. An example of a dipeptide that has been studied is ... Dipeptides have also been shown to self-assemble into hydrogels, another form of nanostructures, when connected to the ... Nanotubes formed from dipeptides are stable under extreme conditions. Dry nanotubes do not degrade until 200 °C; nanotubes ... Nanostructures can be made by dissolving dipeptides in 1,1,1,3,3, 3-hexafluoro-2-propanol at 100 mg/ml and then diluting it ...
"Intestinal absorption of two dipeptides in Hartnup disease". Gut. 11 (5): 380-387. doi:10.1136/gut.11.5.380. PMC 1411553. PMID ...
Giessen; A. Marahiel, Tobias; Mohamed (August 2014). "The tRNA-Dependent Biosynthesis of Modified Cyclic Dipeptides". ...
Artis, Dean R.; Lipton, Mark A. (1998). "Conformations of Thioamide-Containing Dipeptides: A Computational Study". J. Am. Chem ...
Peptidase and dipeptide esterase activities". The Journal of Biological Chemistry. 243 (15): 4143-50. doi:10.1016/S0021-9258(18 ... This enzyme catalyses the following chemical reaction: Release of an N-terminal dipeptide, Xaa-Yaa!, preferentially when Yaa is ...
1990). "Fluoroolefin dipeptide isosteres -II". Tetrahedron Letters. 31 (50): 7301. doi:10.1016/s0040-4039(00)88549-4. Nishikawa ...
It is a cyclic dipeptide. Barettin is the major compound in the deep-sea sponge Geodia barretti. It was isolated for the first ...
Dipeptide Tetrapeptide Nelson, David L.; Cox, Michael M. (2005). Principles of Biochemistry (4th ed.). New York: W. H. Freeman ...
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... s are secreted onto the brush border of the villi in the small intestine, where they cleave dipeptides into their ... They are also found within the enterocytes themselves, performing cytosolic digestion of absorbed dipeptides. Dipeptidases are ... Dipeptidases hydrolyze bound pairs of amino acids, called dipeptides. ...
Kaiser RI, Stockton AM, Kim YS, Jensen EC, Mathies RA (2013). "On the Formation of Dipeptides in Interstellar Model Ices". The ...
By self-assembling of dendritic dipeptides, hollow cylinders can be produced. The cylindrical assemblies possess internal ... "Self-assembly of amphiphilic dendritic dipeptides into helical pores". Nature. 430 (7001): 764-8. Bibcode:2004Natur.430..764P. ...
"Self-assembly of amphiphilic dendritic dipeptides into helical pores". Nature. 430 (7001): 764-768. Bibcode:2004Natur.430..764P ...
A dipeptide has two amino acids. A tripeptide has three amino acids. A tetrapeptide has four amino acids. A pentapeptide has ... Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. ...
Amino acids can also form dimers, which are called dipeptides. An example is glycylglycine, consisting of two glycine molecules ...
Experiments with sulfides in an aqueous environment at 100 °C produced a small yield of dipeptides (0.4% to 12.4%) and a ... smaller yield of tripeptides (0.10%). However, under the same conditions, dipeptides were quickly broken down. Several models ...
Tap and Tsr recognize dipeptides and serine as chemoattractants, respectively. Chemoattractants or chemorepellents bind MCPs at ...
Bracco, S.; Asnaghi, D.; Negroni, M.; Sozzani, P.; Comotti, A. (2018). "Porous dipeptide crystals as volatile-drug vessels". ...
Huperzine A. Dipeptide D-Phe-L-Tyr. weakly inhibit NMDA/Gly-induced currents possibly by ifenprodil-like mechanism. Ibogaine: a ...
For example, the dipeptide Ala-Gln has the solubility of 586 g/L more than 10x the solubility of Gln (35 g/L). Dipeptides also ... A well known dipeptide is aspartame, an artificial sweetener. Dipeptides are white solids. Many are far more water-soluble than ... Dipeptides activate G-cells found in the stomach to secrete gastrin. Diketopiperazines are a special class of dipeptides, which ... Dietary proteins are digested to dipeptides and amino acids, and the dipeptides are absorbed more rapidly than the amino acids ...
Conformational study of dipeptides: A sensitivity analysis approach. Roberta Susnow, Clarence Schutt, Herschel Rabitz, Shankar ... Dive into the research topics of Conformational study of dipeptides: A sensitivity analysis approach. Together they form a ...
表面活性剂百科(Surfactant.TOP | SAAPedia.org)是一个专业的表
How many dipeptides are possible by the reaction of glycine and alanine?. Ask Question ... How many dipeptides are possible by the reaction of glycine and alanine? ...
ABSTRACT: In this study, we report that the insertion of a pseudoproline dipeptide for the solid-phase peptide synthesis of ... KEYWORDS: Solid-State Peptide Synthesis; Pseudoproline Dipeptide; Phospholamban JOURNAL NAME: Open Journal of Synthesis Theory ... TITLE: Improved Solid-Phase Peptide Synthesis of Wild-Type and Phosphorylated Phospholamban Using a Pseudoproline Dipeptide ...
INCI & Tgas : Glycerin & Aqua & Palmitoyl Dipeptide‐5 Diaminobutyloyl Hydroxythreonine & Palmitoyl Dipeptide‐5 ...
Dipeptide "alaptide" prevented impairments in spontaneous behavior produced with trimethyltin in male rats.. Hlinak Z, Krejci I ... Hlinak Z, Krejci I, Hynie S, Klenerova V. Dipeptide "alaptide" prevented impairments in spontaneous behavior produced with ...
Abstract This study was carried out to evaluate the effect of Glutamine, as a dipeptide or a free amino acid form, on the ... Oral glutamine dipeptide or oral glutamine free amino acid reduces burned injury progression in rats ... Oral glutamine dipeptide or oral glutamine free amino acid reduces burned injury progressi ... and treated groups that orally received Glutamine as dipeptide (G2-Dip) or free amino acid (G3-FreeAA). Two and seven days ...
... typically contains a GH dipeptide 11-24 residues from .... ... typically contains a GH dipeptide 11-24 residues from .... ... typically contains a GH dipeptide 11-24 residues from .... ... typically contains a GH dipeptide 11-24 residues from .... ... typically contains a GH dipeptide 11-24 residues from .... ... typically contains a GH dipeptide 11-24 residues from .... ...
Specifically, prolidase divides dipeptides containing the amino acids proline or hydroxyproline. By freeing these amino acids, ... Researchers have suggested that accumulation of dipeptides that have not been broken down may lead to cell death. When cells ... Prolidase helps divide certain dipeptides, which are molecules composed of two protein building blocks (amino acids. ). ...
Compound: Dipeptide and tripeptide permease A. Species: Escherichia coli K-12 [TaxId:83333]. Gene: dtpA, tppB, ydgR, b1634, ...
Attractive interactions between side chains of histidine-histidine and histidine-arginine-based cationic dipeptides in water. J ...
Dietary muramidase degrades bacterial peptidoglycan to NOD-activating muramyl dipeptides and reduces duodenal inflammation in ...
Introduction of the worlds first dipeptide solution for parenteral nutrition. Inauguration of the state-of-the-art infusions ...
Afonso, R. V., Durão, J., Mendes, A., Damas, A. M., & Gales, L. (2010). Dipeptide crystals as excellent permselective materials ... Durão, J., & Gales, L. (2013). Guest diffusion in dipeptide crystals. CrystEngComm, 15(8), 1532 - 1535.*Google Scholar ... Afonso, R., Mendes, A., & Gales, L. (2014). Hydrophobic dipeptide crystals: A promising Ag-free class of ultramicroporous ...
In addition, a novel mechanism of poly-dipeptide production, repeat-associated non-ATG translation (RAN) [52] has been shown to ...
Blood-brain barrier permeability to dipeptides and their constituent amino acids Brain Res. 1983 Jul 18; 271(1):65-71. . View ...
The RNAi let these worms live longer and it decreased the number of RNAi foci and the amount of dipeptide repeat proteins. They ... The idea is that these foci and weird dipeptide proteins are at least part of the reason why these folks have their ALS ... So it looks like targeting SUPT4H1 may be a good strategy for dealing with ALS if the RNA foci and dipeptide repeat proteins ... These RNAs get translated by a process called repeat-associated non-ATG, or RAN, which causes a buildup of dipeptide repeat ...
Carnosine is a natural dipeptide that has generated particular interest for its antioxidant, anti-aging and especially for its ... Carnosine is a natural dipeptide that has generated particular interest for its antioxidant, anti-aging and especially for its ...
... prevention by hydrolyzed whey protein enriched with glutamine dipeptide. European Journal of Applied Physiology, 103(3), 289- ...
One of the major hypotheses for toxicity is the accumulation of dipeptide repeat (DPR) proteins produced by RNA repeats. There ...
The effect of l-alanyl-l-glutamine dipeptide supplemented total parenteral nutrition on infectious morbidity and insulin ...
... dipeptide motif. To obtain structural insight into the ligandability of this pocket, a novel construct was designed fusing ...
Dipeptides Containing Pyrene and Modified Photochemically Reactive Tyrosine: Noncovalent and Covalent Binding to ...
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This enzyme uses the energy released by removing the peptide bond between Cys and Gly to condensate the γ-Glu-Cys dipeptide to ...
Abstract: Dipeptide nitrile Cathepsin K inhibitors of formula I, and pharmaceutically acceptable salts or esters thereof: In ... Abstract: N-terminal substituted dipeptide nitriles as defined are useful as inhibitors of cysteine cathepsins, e.g. cathepsins ... Particular dipeptide nitriles are compounds of formula I, or physiologically-acceptable and -cleavable esters or a salts ...
... parvum protein with an additional GlySer dipeptide at the amino terminus was released by overnight cleavage with thrombin at ...
... cleaving Xaa-Pro dipeptides from the N-termini of proteins. Increased activity of this protein is associated with endometrial ...
Alzheimers DiseaseMolecular ProbesDiagnostic TherapyMolecular ArchitectonicsSilk & Cyclic Dipeptide Biomaterials ... Molecular self‐assembly of cyclic dipeptide derivatives and their applications. S Manchineella, T Govindaraju ...
  • Abstract This study was carried out to evaluate the effect of Glutamine , as a dipeptide or a free amino acid form, on the progression of burn injuries in rats . (bvsalud.org)
  • The animals were randomized into three groups (n=10) saline solution (G1-Control) and treated groups that orally received Glutamine as dipeptide (G2-Dip) or free amino acid (G3-FreeAA). (bvsalud.org)
  • Patients will be randomized to receive glutamine dipeptide or not receive glutamine dipeptide (control group). (who.int)
  • In the glutamine dipeptide group, (N(2)-L-Alanyl-L-Glutamine Dipeptide, (Dipeptiven), by Fresenius Laboratories, Germany) will be given IV in a dose of 20 gm/100ml on the day 1-2 regimen every 2 weeks. (who.int)
  • esterification of the C terminal residue is free from enantiomerization and dipeptide formation 7 because attachment does not involve activation of the incoming protected amino acid ( Method 5 ). (sigmaaldrich.com)
  • To appraise the utility as biomarkers of blood antibodies and immune complexes to neurofilaments and dipeptide repeat proteins, the products of translation of the most common genetic mutation in amyotrophic lateral sclerosis (ALS). (nih.gov)
  • Antibodies and immune complexes against neurofilament light, medium, heavy chains as well as poly-(GP)-(GR) dipeptide repeats were measured in blood samples from the ALS Biomarkers (n = 107) and the phenotype-genotype biomarker (n = 129) studies and in 140 healthy controls. (nih.gov)
  • The species distribution and stability constants were evaluated for six mixed imidazole (A)-dipeptide (B) complexes of Cu(II) in aqueous perchlorate medium at I = 0.15 M (NaClO 4 ) and 37°C from pH titration data. (ias.ac.in)
  • The stability order found for these complexes is discussed in terms of the steric effects due to side chain substituents in the dipeptide (B) ligands. (ias.ac.in)
  • The amide deprotonated dipeptides (B) appear to be tridentate in the CuA 2 BH -1 and CuABH -1 complexes. (ias.ac.in)
  • In the search for new cytotoxic drugs, two copper complexes with isomeric dipeptides (Ala-Phe and Phe-Ala) were developed in order to determine the influence of their different structures in the modulation of the chemical, biochemical and biological properties. (fq.edu.uy)
  • These experiments showed that both Cu-dipeptide complexes have a similar cytotoxic effect against breast cancer cells, and lower toxicity against BJ non-tumor cells in comparison to Cisplatin. (fq.edu.uy)
  • Facchin, Gianella, "Experimental and theoretical studies of copper complexes with isomeric dipeptides as novel candidates against breast cancer," RIQUIM - Repositorio Institucional de la Facultad de Química - UdelaR , accessed April 14, 2024, https://riquim.fq.edu.uy/items/show/4388. (fq.edu.uy)
  • Dietary proteins are digested to dipeptides and amino acids, and the dipeptides are absorbed more rapidly than the amino acids, because their uptake involves a separate mechanism. (wikipedia.org)
  • Diphenylalanine is the most studied building block in peptide nanotechnology Kyotorphin (L-tyrosyl-L-arginine) is a neuroactive dipeptide which plays a role in pain regulation in the brain. (wikipedia.org)
  • The Bergmann azlactone peptide synthesis is a classic organic synthesis for the preparation of dipeptides. (wikipedia.org)
  • ABSTRACT: In this study, we report that the insertion of a pseudoproline dipeptide for the solid-phase peptide synthesis of wild-type Phospholamban protein (WT-PLB) has two important advantages. (scirp.org)
  • Dipeptide "alaptide" prevented impairments in spontaneous behavior produced with trimethyltin in male rats. (nel.edu)
  • Hlinak Z, Krejci I, Hynie S, Klenerova V. Dipeptide "alaptide" prevented impairments in spontaneous behavior produced with trimethyltin in male rats. (nel.edu)
  • A dipeptide is an organic compound derived from two amino acids. (wikipedia.org)
  • How many dipeptides are possible by the reaction of glycine and alanine? (stackexchange.com)
  • We report a distinctive humoral response characterized by raising antibodies against neurofilaments and dipeptide repeats in faster progressing and C9orf72 genetic mutation carriers ALS patients. (nih.gov)
  • The nucleotide-binding oligomerization domain 2 (NOD2) protein plays a key role in innate immunity as a sensor of muramyl dipeptide (MDP), a breakdown product of bacterial peptidoglycan. (nih.gov)
  • Muramyl dipeptide activation of nucleotide-binding oligomerization domain 2 protects mice from experimental colitis. (nih.gov)
  • L-NIL also effectively inhibited NF-kappaB activation induced by other inflammatory stimulants, such as lipopolysaccharide (LPS) or muramyl dipeptide (MDP). (cdc.gov)
  • Antibodies and immune complexes against neurofilament light, medium, heavy chains as well as poly-(GP)-(GR) dipeptide repeats were measured in blood samples from the ALS Biomarkers (n = 107) and the phenotype-genotype biomarker (n = 129) studies and in 140 healthy controls. (nih.gov)
  • To appraise the utility as biomarkers of blood antibodies and immune complexes to neurofilaments and dipeptide repeat proteins, the products of translation of the most common genetic mutation in amyotrophic lateral sclerosis (ALS). (nih.gov)
  • The RNA also generates toxic proteins called dipeptide repeat proteins. (nih.gov)
  • Carnosine, a dipeptide of l -histidine and BA, occurs in high concentrations in human skeletal muscles ( 11 ). (frontiersin.org)
  • Along with zinc and copper, the dipeptide carnosine also is found in the olfactory system. (nih.gov)
  • L-Carnosine is a dipeptide antioxidant found in the brain, heart, skin, muscles, kidneys and stomach that supports mitochondrial health. (myvillagegreen.com)
  • However, chains of fewer than ten or fifteen amino acid bonds are called oligopeptides that including dipeptides, tripeptides, and tetrapeptides. (vedantu.com)
  • 18. Histamine synthesis, imidazole dipeptides, and wound healing. (nih.gov)
  • Cell proliferative activity as a fundamental property of a natural dipeptide inherent to traditional antioxidant, anti-aging biological activities: balancing and a hormonally correct agent, novel patented oral therapy dosage formulation for mobility, skeletal muscle power and functional performance, hypothalamic-pituitary- brain relationship in health, aging and stress studies. (nih.gov)
  • Short chains may be known by terms which indicate the number of amino acids in the grouping, as in the case of dipeptides, while longer chains are known simply as polypeptides, referencing the fact that they contain many amino acids. (allthescience.org)
  • Numerous dipeptides are found in nature, performing a variety of functions, and they can also be made in laboratory environments. (allthescience.org)
  • By using NMR experiments, it was found that strains inactivated in asnO and ngg were unable to produce the dipeptide. (nih.gov)
  • Kyotorphin, a dipeptide found in the brain, helps regulate pain. (allthescience.org)
  • Numerous dipeptides can be found in the body. (allthescience.org)
  • Unravelling glutathione conjugate catabolism in Saccharomyces cerevisiae: the role of glutathione/dipeptide transporters and vacuolar function in the release of volatile sulfur compounds 3-mercaptohexan-1-ol and 4-mercapto-4-methylpentan-2-one. (oregonstate.edu)
  • Dipeptides have a number of commercial and industrial uses in addition to playing an important role in the biology of many species on Earth. (allthescience.org)
  • Other dipeptides do things like reducing fatigue and playing a role as antioxidants. (allthescience.org)
  • Researchers who work with amino acids are often interested in identifying dipeptides and learning about their function, in addition to researching known dipeptides to learn more about them. (allthescience.org)
  • At least one dipeptides actually signals the body to produce enzymes which can be used in digestion. (allthescience.org)
  • The dipeptide N-acetylglutaminylglutamine amide (NAGGN) was discovered in the bacterium Sinorhizobium meliloti grown at high osmolarity, and subsequently shown to be synthesized and accumulated by a few osmotically challenged bacteria. (nih.gov)
  • Additional study suggested that while this dipeptide could be dangerous for some people in high quantities, the low level use of aspartame as an artificial sweetener was probably not a cause for concern. (allthescience.org)
  • 7. Scavenging of singlet molecular oxygen by imidazole compounds: high and sustained activities of carboxy terminal histidine dipeptides and exceptional activity of imidazole-4-acetic acid. (nih.gov)