• In particular, the availability of substrate and inhibitor "probes" for the major hepatic drug metabolizing UGTs together with batteries of recombinant enzymes allow the reaction phenotyping of drug glucuronidation reactions. (nih.gov)
  • This observation was verified by modeling enzyme-substrate and enzyme-inhibitor complexes, which also showed the geometry of the catalyzed reaction. (rcsb.org)
  • An enzyme is a biological catalyst that regulates the rate of a chemical reaction in a living organism. (newworldencyclopedia.org)
  • Yet, a denatured enzyme can refold within fractions of a second and then precisely react in a chemical reaction. (newworldencyclopedia.org)
  • Like all catalysts, enzymes work to lower the activation energy of a reaction, or the initial energy input necessary for most chemical reactions to occur. (newworldencyclopedia.org)
  • Heat cannot be added to a living system, so enzymes provide an alternate pathway: they bond with a substrate (the substance involved in the chemical reaction) to form a "transition state," an unstable intermediate complex that requires less energy for the reaction to proceed. (newworldencyclopedia.org)
  • Like any catalyst, the enzyme remains unaltered by the completed reaction and can therefore continue to interact with substrates. (newworldencyclopedia.org)
  • This region, where the binding of the substrate(s) and the reaction occur, is known as the active site of the enzyme. (newworldencyclopedia.org)
  • The synthesis of the peptide stem of bacterial peptidoglycan involves four enzymes, the Mur ligases (MurC, D, E and F). Among them, MurD is responsible for the ATP-dependent addition of d -glutamic acid to UDP-MurNAc- l -Ala, a reaction which involves acyl-phosphate and tetrahedral intermediates. (degruyter.com)
  • In the present review, we will deal with work performed on substrate specificity, reaction mechanism and 3D structure of E. coli MurD. (degruyter.com)
  • Enzymes are often used in these sensors because of their specificity and the reaction products can be electrochemically transduced for the measurement. (materialstoday.com)
  • The DGAT, which catalyzes the acylation reaction at the sn-3 position of the glycerol backbone, represents the only enzyme unique to the biosynthesis pathway of TAG [45]. (usda.gov)
  • While conventional methods can be plagued by harsh reaction conditions, corrosive reagents and costly protecting groups, enzymes and catalytic antibodies have high substrate specificity. (aiche.org)
  • The enzyme-substrate reaction is terminated by the addition of stop solution and the color turns yellow. (caslab.com)
  • Hydrolysis of the substrate by peroxidase produces a color change. (cdc.gov)
  • There is a substantial variation among individuals within a population due to genetic and environmental factors, including the Q192R polymorphism, which affect the efficiency of substrate hydrolysis. (cdc.gov)
  • Once partial deacetylation has been accomplished either by enzymes, or by partial chemical hydrolysis, the polymer's cellulose backbone is readily biodegraded. (springer.com)
  • 9 This enzyme, together with the collagenase produced by neutrophils and classified as MMP-8, are the only mammalian enzymes known to be capable of initiating hydrolysis of fibrillar type I collagen, 2 10 the major component of the corneal stroma. (bmj.com)
  • Ironically, the H-N-H motif of the E9 DNase although resembling the zinc binding site of a metalloenzyme does not support zinc-mediated hydrolysis of any DNA substrate. (gla.ac.uk)
  • A model of this "sister enzyme" derived from known homologous structures suggests that the reported L-substrate specificity and D-enantiomer inhibition are also determined by the location of the deprotonating base. (rcsb.org)
  • 1959 ) Mechanism of enzyme inhibition by phosphate esters Science . (academictree.org)
  • Studies of chemical recognition in biology were initiated about half a century ago with the flrst kinetic data obtained on enzyme catalysis and inhibition. (powells.com)
  • Here, we show that, the H-N-H enzyme from colicin E9 (the E9 DNase) shares many of the same basic enzymological characteristics as sequence-specific H-N-H enzymes including a dependence for high concentrations of Mg2+ or Ca2+ with double-stranded substrates, a high pH optimum (pH 8-9) and inhibition by monovalent cations. (gla.ac.uk)
  • We also show that this seemingly nonspecific enzyme preferentially nicks double-stranded DNA at thymine producing 3'-hydroxy and 5'-phosphate termini, and that the enzyme does not cleave small substrates, such as dinucleotides or nucleotide analogues, which has implications for its mode of inhibition in bacteria by immunity proteins. (gla.ac.uk)
  • For more than 30 years, his main research interests have been the functional and structural study of the enzymes of peptidoglycan biosynthesis, the determination of the structure of peptidoglycan from certain bacterial species, and the search for peptidoglycan biosynthesis inhibitors that could act as antibacterial agents. (degruyter.com)
  • Like most enzymes of peptidoglycan biosynthesis, MurD constitutes an attractive target for the design and synthesis of new antibacterial agents. (degruyter.com)
  • Deciphering the Substrate Specificity of SbnA, the Enzyme Catalyzing the First Step in Staphyloferrin B Biosynthesis. (cathdb.info)
  • Genes in region A encode enzymes for biosynthesis of the capsular polysaccharide, and genes in regions B and C are implicated in the translocation of the high molecular weight polysaccharides to the cell surface. (cdc.gov)
  • The Acyl CoA:diacylglycerol (DGAT) is a membrane enzyme that catalyses the final step in TAG biosynthesis. (usda.gov)
  • Structure and substrate specificity determinants of the taurine biosynthetic enzyme cysteine sulphinic acid decarboxylase. (uib.no)
  • Dr. Mundorff's research interests are in the investigation of determinants of enzyme substrate specificity, using both study of mutants and computer modeling using specialized molecular modeling software. (hofstra.edu)
  • This difference in substrate sensitivity may be due to the lower enzyme specificity of phenyl acetate. (cdc.gov)
  • With any type of laboratory test, the clinical accuracy or reliability depends on performance characteristics such as sensitivity and specificity, as well as the pretest probability that a person has SARS-CoV-2 infection and the prevalence of COVID-19 in the local community. (medscape.com)
  • For any given substrate, enzyme specificity, enzyme content, substrate binding affinity and sensitivity to irreversible catalytic events all play a role in determining the overall efficiency, or intrinsic clearance, of elimination. (nih.gov)
  • CHROMagar Candida™ medium (CC) is a differential culture medium that allows the presumptive identification of yeasts species, with sensitivity and specificity higher than 99% to C. albicans 10 . (bvsalud.org)
  • In several cases, crystallographic studies of enzyme-substrate complexes have supported this model. (powells.com)
  • The mode of action of enzymes and macromolecular complexes as protein machines will be investigated. (manchester.ac.uk)
  • More recently we have probed the allosteric regulation of class II and class III RNRs by solving the structures of complexes with several combinations of allosteric effector and substrate [2,5]. (lu.se)
  • Disintegrin and metalloproteinase domain-containing protein 33 is an enzyme that in humans is encoded by the ADAM33 gene. (wikipedia.org)
  • Whereas the substrate specificities of γ-GCS domain protein and GS domain protein of S. agalactiae γ-GCS-GS were the same as those of S. agalactiae γ-GCS-GS. (elsevierpure.com)
  • Enzyme activity assays with crude beetle protein extracts revealed that glucosinolate sulfatase (GSS) activity is associated with the gut membrane and has narrow substrate specificity towards the benzenic glucosinolate sinalbin. (nature.com)
  • For instance, many household cleaners use enzymes to speed up the breakdown of protein or starch stains on clothes. (newworldencyclopedia.org)
  • [9] A second protein, referred to as debranching enzyme, performs α-1,6-glucose cleavage. (wikidoc.org)
  • With these models it has been possible to examine sources of interindividual variability in drug bioavailability including, variable constitutive enzyme expression (both genetic and environmentally determined), enzyme induction by drugs, disease and diet, and intrinsic or acquired differences in plasma protein binding and organ blood flow (food and drug effects). (nih.gov)
  • However, the biochemical basis for the combined enzyme deficiency is a loss of a protective protein that interacts with both enzymes to produce catalytic activity. (medscape.com)
  • Class I enzymes are totally O 2 -dependent and generate a stable tyrosyl radical on the protein through activation of O 2 by a di-iron centre. (lu.se)
  • A small chain of 150 amino acids making up an enzyme has an extraordinary number of possible folding configurations: if it tested 10 12 different configurations every second, it would take about 10 26 years to find the right one (Lewis 2005). (newworldencyclopedia.org)
  • An enzyme might contain only one polypeptide chain, typically linking one hundred or more amino acids, or it might consist of several polypeptide chains that act together as a unit. (newworldencyclopedia.org)
  • Only a very small portion of the enzyme, approximately ten amino acids, comes into direct contact with the substrate(s). (newworldencyclopedia.org)
  • The amino acids side chains that make up the active site are molded into a precise shape, which enables the enzyme to perform its catalytic function. (newworldencyclopedia.org)
  • The enzyme shows only a slight preference for basic amino acids in the P1 and P3 positions and a preference for aliphatic amino acids such as Ile, Pro, Val, Leu and norleucine in the P4 position. (expasy.org)
  • Finally, some reactive esters of N-acetylated amino acids have been evaluated as substrates of α-chymotrypsin. (caltech.edu)
  • In agreement with GSS activity localization in vivo , we identified six genes encoding arylsulfatase-like enzymes with a predicted C-terminal transmembrane domain, of which five showed GSS activity upon heterologous expression in insect cells. (nature.com)
  • His main research interests concern the identification of genes and enzymes involved in this pathway, the regulation of this metabolism, the mode of action of antibiotics and bacteriocins interfering with this pathway and the corresponding resistance mechanisms, as well as the molecular bases for the recognition of bacterial cell-wall peptidoglycan by host innate immunity mechanisms. (degruyter.com)
  • Doubtless, the availability of multiple cloned genes for this enzyme, the capacity of the enzyme for channeling specific fatty acids to TAG, and the significant effect of the activity on oil yield have made the DGAT enzyme a new target for future development of new, high quantity and quality oils suitable for specific commercial utilizations, especially when used with other enzymes directing the synthesis of some unusual fatty acids. (usda.gov)
  • Genes encoding this enzyme have been cloned from several plant species. (usda.gov)
  • Southern blot analyses indicate that the genes encoding DGAT enzymes are only present as a single copy in many plant genomes. (usda.gov)
  • How- ever, this does not necessarily result from a direct recognition process between rigid structures, but may result from a progressive adaptation during which the initial struc- tures of the enzyme and the ligand are modified (induced-flt mechanism). (powells.com)
  • The matrix metalloproteinases (MMPs) are a family of zinc and calcium ion dependent enzymes 1 of differing substrate specificity but similar structure and catalytic mechanism. (bmj.com)
  • We are also determining the structure of other class III RNRs which have overall activity regulation (the T4 enzyme does not), as well as of mutants of the T4 RNR which affect the catalytic mechanism and the allosteric regulation. (lu.se)
  • The active site of an enzyme can be modified as the substrate interacts with the enzyme, creating an "induced fit" between enzyme and substrate. (newworldencyclopedia.org)
  • A partial model of the locus of the active site which interacts with the R' 1 CONH- group of a substrate of the form R' 1 CONHCHR 2 COR' 3 is proposed. (caltech.edu)
  • In some cases, the substrate molecule changes shape slightly as it enters the active site. (newworldencyclopedia.org)
  • His main research interests are the structure-based design, synthesis and evaluation of small-molecule enzyme inhibitors and receptor ligands. (degruyter.com)
  • Dr. Jaremko's research interests are in the investigation of enzymes involved in natural product pathways, including fatty acids and non-ribosomal peptides (pharmaceuticals), using small molecule probes and inhibitors. (hofstra.edu)
  • A debranching enzyme is a molecule that helps facilitate the breakdown of glycogen , which serves as a store of glucose in the body, through glucosyltransferase and glucosidase activity. (wikidoc.org)
  • A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts. (bvsalud.org)
  • Whereas there remains much to learn about the potential biological relevance of UGTs, deficient glucuronidation can result in either elevated tissue concentrations and direct toxicity of substrates, as with the endobiotic bilirubin, or, alternatively, enhanced bioactivation of substrates to toxic reactive intermediates, as in the case of acetaminophen and benzo[ a ]pyrene. (aspetjournals.org)
  • Enzymes (and other proteins) are composed of amino acid chains called polypeptide chains. (newworldencyclopedia.org)
  • The results are interpreted in terms of the available specificity theories and are compared with results obtained in the study of polypeptide substrates. (caltech.edu)
  • For the research on glycosyltransferases, funded by DFG-SFB 578, recombinant high-level expression systems have been constructed and are used to investigate the acceptor substrate specificity of the glycosyltransferase R (GtfR). (helmholtz-hzi.de)
  • The importance of non-productive binding in determining the kinetic parameters of these substrates is discussed. (caltech.edu)
  • CUPRA-ZYME: An Assay for Measuring Carbohydrate-Active Enzyme Activities, Pathways, and Substrate Specificities. (bvsalud.org)
  • 1955 ) A simple model of molecular specificity in enzyme-substrate systems. (academictree.org)
  • This enzyme has a molecular mass of 73.6 kDa, and is coded for by the gene glgX. (wikidoc.org)
  • So-called lock-and-key interactions, i. e., the preferred association of molecular building blocks with complementary shapes, are omnipresent in biology, where they for example describe the interactions between enzymes and their substrates. (lu.se)
  • These enzymes catalyze the conversion of aldehydes and ketones to their corresponding alcohols by utilizing NADH and/or NADPH as cofactors. (cancerindex.org)
  • Enzymes are usually specific, or unique, to the reactions they catalyze and the substrates that are involved in these reactions. (newworldencyclopedia.org)
  • Sulfotransferase enzymes catalyze the sulfate conjugation of many hormones, neurotransmitters, drugs, and xenobiotic compounds. (origene.com)
  • Proteins that catalyze both functions are referred to as glycogen debranching enzymes (GDEs). (wikidoc.org)
  • In humans, both hepatic and intestinal enzymes can catalyze the metabolism of a drug as it transits between the gastrointestinal lumen and systemic blood for the first time. (nih.gov)
  • Recent studies have revealed an extensive superfamily of UDP-glucuronosyltransferases (UGTs), 2 previously termed glucuronyl transferases, which catalyze the conjugation of UDP-glucuronic acid with lipid-soluble substrates to form polar conjugates that are excreted in the urine and feces. (aspetjournals.org)
  • These studies have provided fundamental insights into UGT gene structure and regulation, isozyme substrate selectivity, and interindividual variability. (aspetjournals.org)
  • The enzymes display overlapping but distinct substrate specificity. (cancerindex.org)
  • Glucosyltransferase and glucosidase are performed by a single enzyme in mammals, yeast, and some bacteria, but by two distinct enzymes in E. coli and other bacteria, complicating nomenclature. (wikidoc.org)
  • When glucosyltransferase and glucosidase are catalyzed by distinct enzymes, "glycogen debranching enzyme" usually refers to the glucosidase enzyme . (wikidoc.org)
  • In E. coli and other bacteria, glucosyltransferase and glucosidase functions are performed by two distinct enzymes. (wikidoc.org)
  • The specificity of these accumulated materials to the distinct enzyme defect is striking in the lysosomal disorders, and the accumulation then leads to abnormal cell architecture. (medscape.com)
  • This gene encodes a member of the aldo/keto reductase superfamily, which consists of more than 40 known enzymes and proteins. (cancerindex.org)
  • The structural specificity of α-chymotrypsin for polypeptides and denatured proteins has been examined. (caltech.edu)
  • Enzyme structure is important because it determines the enzyme's particular function in the body. (newworldencyclopedia.org)
  • dNTP products regulate the enzyme's specificity for the NTP or NDP substrates. (lu.se)
  • In the context of current structural information, our data show that the H-N-H motif is an adaptable catalytic centre able to hydrolyse nucleic acid by different mechanisms depending on the substrate and metal ion regime. (gla.ac.uk)
  • Major advances in the characterization of uridine diphosphate (UDP)-glucuronosyltransferase (UGT) enzyme substrate and inhibitor selectivities and the development of experimental paradigms to investigate xenobiotic glucuronidation in vitro now permit the prediction of a range of drug-glucuronidation parameters in humans. (nih.gov)
  • Studies on specificities of the DGAT enzyme for substrates demonstrated that the DGAT had pronounced selectivities for acyl donors and acyl acceptors with both 'common' and 'uncommon' fatty acids. (usda.gov)
  • N-acylated peptide esters as substrates. (caltech.edu)
  • A series of N-acetylated peptide esters of varying length have been evaluated as substrates of α-chymotrypsin. (caltech.edu)
  • Activity is regulated on two levels: overall activity and substrate specificity (as only one RNR catalyses the reduction of all four ribonucleotides under given physiological conditions). (lu.se)
  • This enzyme catalyzes the reduction of prostaglandin (PG) D2, PGH2 and phenanthrenequinone (PQ), and the oxidation of 9alpha,11beta-PGF2 to PGD2. (cancerindex.org)
  • Aspirin works by inhibiting COX-1 and COX-2, the enzymes that produce prostaglandin, a hormonal messenger that signals inflammation. (newworldencyclopedia.org)
  • Thus the debranching enzymes, transferase and α-1,6- glucosidase converts the branched glycogen structure into a linear one, paving the way for further cleavage by phosphorylase. (wikidoc.org)
  • Indeed, in a crystallized ligand-enzyme complex, a close fltting is observed between the active center of the enzyme and the functional groups of the ligand. (powells.com)
  • Bernhard SA, Lau SJ, Noller H. ( 1965 ) Spectrophotometric identification of acyl enzyme intermediates. (academictree.org)
  • We revealed that in the γ-GCS activity, S. agalactiae γ-GCS-GS had different substrate specificities from those of Escherichia coli γ-GCS. (elsevierpure.com)
  • Enzymes are essential to sustain life because most chemical reactions in biological cells , such as the digestion of food, would occur too slowly or would lead to different products without the activity of enzymes. (newworldencyclopedia.org)
  • Enzymes can be affected by molecules that increase their activity (activators) or decrease their activity (inhibitors). (newworldencyclopedia.org)
  • By inhibiting the activity of these enzymes, aspirin suppresses our experience of pain and inflammation. (newworldencyclopedia.org)
  • The data suggest that the proteolytic specificity and activity depend on the formation of dimers of C3 with C3b of the convertase. (rcsb.org)
  • PON1 activity and Q192R phenotype were determined using phenyl acetate and CMPA [4- (Chloromethyl)phenyl acetate] as substrates. (cdc.gov)
  • [10] Activity of the two enzymes is not always necessarily coupled. (wikidoc.org)
  • Because of the observed correlation between tear film MMP content and clinical evidence of PUK progression, it has been suggested that the zymographic visualisation of these enzymes in tears could be reliably used as a monitor of disease activity. (bmj.com)
  • Direct visualization of cholinesterase activity on polyacrylamide gels is routinely practiced using acetylthiocholine as a substrate. (who.int)
  • Overnight incubation with the staining solution is required to understand the enzyme activity bands on gels. (who.int)
  • Here, we have explored alternative substrates, such as 1-NA and 2-NA which might have the potential to behave as specific substrates for the detection of hemolysate cholinesterase activity on the gels. (who.int)
  • Moreover, the enzyme activity bands formed using 1-NA proves the specificity of the substrate for hemolysate cholinesterase as in the presence of specific acetylcholinesterase inhibitors the band formation disappears. (who.int)
  • On the other hand, ATCh requires minimum 8-12 h staining time for detection of enzyme activity band following Karnovsky and Roots protocol. (who.int)
  • Our results prove that 1-NA is an alternative substrate of hemolysate cholinesterase which specifically detects the enzyme activity on gel rapidly. (who.int)
  • In addition, they have among the most complex allosteric regulations of any enzyme system. (lu.se)
  • These media contains chromogenic substrates that react with yeast enzymes, resulting in colored colonies 9 . (bvsalud.org)
  • In lysosomal storage disorders, the deficiency of a specific lysosomal enzyme interrupts the normal catabolic pathway, resulting in the cellular accumulation of substrates ordinarily degraded by that enzyme. (medscape.com)
  • While the enzyme is more active with D-tryptophan than L-tryptophan, its only known function to date is in the metabolism of L-tryptophan [2,6]. (genome.jp)
  • These cytosolic enzymes are different in their tissue distributions and substrate specificities. (origene.com)
  • 2 Physiologically, these enzymes participate in tissue remodelling 3-5 and, pathologically, they cause disruption or disintegration of extracellular matrices. (bmj.com)
  • Most inherited human diseases result from a genetic mutation , overproduction, or deficiency of a single critical enzyme. (newworldencyclopedia.org)
  • During our work in recent years on the genetic engineering of enzyme substrate specificities, we have obtained substantial expertise in biotransformations involving two different families of enzymes, aryl-hydroxylating dioxygenases and sucrose-utilizing glycosyltransferases. (helmholtz-hzi.de)
  • Her main research interests have been the study of Mur ligases from different bacterial species and the search for inhibitors of these enzymes. (degruyter.com)
  • Colicin endonucleases and the H-N-H family of homing enzymes share a common active site structural motif that has similarities to the active sites of a variety of other nucleases such as the non-specific endonuclease from Serratia and the sequence-specific His-Cys box homing enzyme I-PpoI. (gla.ac.uk)
  • This was the first structural proof of a common evolutionary origin for the three classes of RNR and also pointed to an evolutionary relationship to the glycyl radical enzyme pyruvate formate lyase (PFL). (lu.se)
  • Through enzyme engineering, applying a metagenomic approach as well as directed and random formats of mutagenesis, we were able to generate libraries of variants possessing diversified substrate ranges that expand our synthetic capabilities for combinatorial compound synthesis. (helmholtz-hzi.de)
  • The gelatinases MMP-2 and MMP-9 are enzymes that will hydrolyse type IV collagen, the major component of basement membranes. (bmj.com)
  • The crystal structure of 6-hydroxy-d-nicotine oxidase (EC 1.5.3.6) was solved by X-ray diffraction analysis in three crystal forms at resolutions up to 1.9 A. The enzyme is monomeric in solution and also in the mother liquor but formed disulfide-dimers in all crystals. (rcsb.org)
  • Each enzyme has a specific three-dimensional structure that determines its function. (newworldencyclopedia.org)
  • Crystal Structure of the Pyrococcus horikoshii Isopropylmalate Isomerase Small Subunit Provides Insight into the Dual Substrate Specificity of the Enzyme. (expasy.org)
  • Thirteen capsular polysaccharides have been described, and nuclear magnetic resonance spectroscopy has enabled determination of the structure of capsular polysaccharides responsible for serogroup specificity. (cdc.gov)
  • Nuclear magnetic resonance spectroscopy enabled determination of the structure of capsular polysaccharides responsible for serogroup specificity, and structures for 12 of the 13 serogroups (all but serogroup D) from N. meningitidis capsular polysaccharides have been reported ( 6 - 15 ). (cdc.gov)
  • The structure specificity of alpha-chymotrypsin. (caltech.edu)
  • The aims of the present investigation were to determine the source of these enzymes and to ascertain whether their accumulation in tears is a phenomenon specific to PUK or a general feature of other anterior segment diseases. (bmj.com)
  • Using a positional scanning combinatorial library, it was found that the major substrate-specificity determinant is for Ala in the P2 position. (expasy.org)
  • The current catalyst range for these processes extends from traditional strong acids and bases, transition metals, and heterogeneous materials to environmentally friendly enzymes and catalytic antibodies. (aiche.org)
  • In contrast to these latter enzymes, however, it remains unclear how H-N-H enzymes cleave nucleic acid substrates. (gla.ac.uk)
  • However, many other CYP3A substrates do not appear susceptible to a gut wall first-pass, possibly because of enzyme saturation during first-pass or a limited intrinsic metabolic clearance. (nih.gov)
  • The MMPs of all samples were visualised by zymography and tear samples were assayed using nitrophenol acetate and an MMP-9 susceptible quenched fluorescent peptide as substrate. (bmj.com)
  • These acids and bases are amino acid side chains in the active site of the enzyme. (wikidoc.org)
  • We have been able to explain how conformational changes a loop spanning the dimer interface communicate the substrate specificity signal to the active site for the class II RNR. (lu.se)
  • Similar movements were observed for the class III enzyme but the full picture has still not been obtained as substrates were not observed to bind to the active site in this system. (lu.se)
  • We continue to try to obtain substrate binding to the active site of class III RNRs. (lu.se)
  • For most xenobiotics and many endobiotics, glucuronidation constitutes a major route of elimination and thereby may substantially modulate substrate concentrations and effects. (aspetjournals.org)
  • [1] When glycogen breakdown is compromised by mutations in the glycogen debranching enzyme, metabolic diseases such as Glycogen storage disease type III can result. (wikidoc.org)
  • It is also clear that some of the substrates for CYP3A4 (e.g., cyclosporine, midazolam, nifedipine, verapamil and saquinavir) undergo significant metabolic extraction by the gut wall. (nih.gov)
  • Hopefully, though, newer models for studying human gut wall metabolic extraction will provide the means to predict the average extraction ratio and maximum first-pass availability of a putative substrate, or the range of possible inhibitory or inductive changes for a putative inhibitor/inducer. (nih.gov)
  • Supported by model calculations, the experiments demonstrate the high specificity of the assembly highlighted by the formation of defined clusters, so-called colloidal molecules. (lu.se)
  • The factors that govern this specificity of UGT expression remain largely unknown. (aspetjournals.org)
  • Glycogen debranching enzymes assist phosphorylase, the primary enzyme involved in glycogen breakdown , mobilize glycogen stores. (wikidoc.org)
  • The primary specificity of the enzyme for these natural substrates is shown to closely correspond to that observed for model substrates. (caltech.edu)
  • C. acetobutylicum GS had broad substrate specificities and synthesized several kinds of γ-glutamyltripeptide, γ-Glu-Cys-X aa . (elsevierpure.com)
  • There are two models to explain how the binding of enzyme and substrate occurs: the "lock and key" model and induced fit. (newworldencyclopedia.org)
  • This model of exact fit, introduced in the 1890s, is often referred to as the "lock and key" model, because the enzyme binding to a substrate is analogous to the specific fit of a lock into a key. (newworldencyclopedia.org)
  • They led to a rather static representation of the recognition process illustrated by the lock and key model that still continues to influence our overall image of recognition and its specificity. (powells.com)
  • The enzyme is specific for 6-hydroxy-D-nicotine and is inhibited by the L-enantiomer. (rcsb.org)
  • However, although this is a possibility, to date there is no information pertaining to the source of these enzymes and whether their appearance in tears is specific to PUK. (bmj.com)
  • His group seeks to trace the evolutionary path by which these enzymes gain the ability to inactivate antibiotics. (hofstra.edu)
  • Together with phosphorylases , debranching enzymes mobilize glucose reserves from glycogen deposits in the muscles and liver. (wikidoc.org)