Crystallization
Crystallography, X-Ray
X-Ray Diffraction
Crystallography
Protein Conformation
Synchrotrons
Calcium Oxalate
Cloning, Molecular
Escherichia coli
Models, Molecular
Molecular Sequence Data
Hemoglobin C
Protein Structure, Tertiary
Amino Acid Sequence
Muramidase
Pyrococcus horikoshii
Volatilization
Detergents
Solubility
Electrophoresis, Polyacrylamide Gel
Solutions
Temperature
Thermus thermophilus
Calcium Carbonate
Proteins
Differential Thermal Analysis
Chemical Precipitation
Polyethylene Glycols
Urinary Calculi
Archaeoglobus fulgidus
Kidney Calculi
Chromatography, Gel
Methanococcaceae
Scattering, Radiation
Protein Structure, Quaternary
Bothrops
Negative Staining
Probing interactions between HIV-1 reverse transcriptase and its DNA substrate with backbone-modified nucleotides. (1/7757)
BACKGROUND: To gain a molecular understanding of a biochemical process, the crystal structure of enzymes that catalyze the reactions involved is extremely helpful. Often the question arises whether conformations obtained in this way appropriately reflect the reactivity of enzymes, however. Rates that characterize transitions are therefore compulsory experiments for the elucidation of the reaction mechanism. Such experiments have been performed for the reverse transcriptase of the type 1 human immunodeficiency virus (HIV-1 RT). RESULTS: We have developed a methodology to monitor the interplay between HIV-1 RT and its DNA substrate. To probe the protein-DNA interactions, the sugar backbone of one nucleotide was modified by a substituent that influenced the efficiency of the chain elongation in a characteristic way. We found that strand elongation after incorporation of the modified nucleotide follows a discontinuous efficiency for the first four nucleotides. The reaction efficiencies could be correlated with the distance between the sugar substituent and the enzyme. The model was confirmed by kinetic experiments with HIV-1 RT mutants. CONCLUSIONS: Experiments with HIV-1 RT demonstrate that strand-elongation efficiency using a modified nucleotide correlates well with distances between the DNA substrate and the enzyme. The functional group at the modified nucleotides acts as an 'antenna' for steric interactions that changes the optimal transition state. Kinetic experiments in combination with backbone-modified nucleotides can therefore be used to gain structural information about reverse transcriptases and DNA polymerases. (+info)Crystal structure of an MHC class I presented glycopeptide that generates carbohydrate-specific CTL. (2/7757)
T cell receptor (TCR) recognition of nonpeptidic and modified peptide antigens has been recently uncovered but is still poorly understood. Immunization with an H-2Kb-restricted glycopeptide RGY8-6H-Gal2 generates a population of cytotoxic T cells that express both alpha/beta TCR, specific for glycopeptide, and gamma/delta TCR, specific for the disaccharide, even on glycolipids. The crystal structure of Kb/RGY8-6H-Gal2 now demonstrates that the peptide and H-2Kb structures are unaffected by the peptide glycosylation, but the central region of the putative TCR binding site is dominated by the extensive exposure of the tethered carbohydrate. These features of the Kb/RGY8-6H-Gal2 structure are consistent with the individual ligand binding preferences identified for the alpha/beta and gamma/delta TCRs and thus explain the generation of a carbohydrate-specific T cell response. (+info)Structural basis of Rab effector specificity: crystal structure of the small G protein Rab3A complexed with the effector domain of rabphilin-3A. (3/7757)
The small G protein Rab3A plays an important role in the regulation of neurotransmitter release. The crystal structure of activated Rab3A/GTP/Mg2+ bound to the effector domain of rabphilin-3A was solved to 2.6 A resolution. Rabphilin-3A contacts Rab3A in two distinct areas. The first interface involves the Rab3A switch I and switch II regions, which are sensitive to the nucleotide-binding state of Rab3A. The second interface consists of a deep pocket in Rab3A that interacts with a SGAWFF structural element of rabphilin-3A. Sequence and structure analysis, and biochemical data suggest that this pocket, or Rab complementarity-determining region (RabCDR), establishes a specific interaction between each Rab protein and its effectors. RabCDRs could be major determinants of effector specificity during vesicle trafficking and fusion. (+info)Phe161 and Arg166 variants of p-hydroxybenzoate hydroxylase. Implications for NADPH recognition and structural stability. (4/7757)
Phe161 and Arg166 of p-hydroxybenzoate hydroxylase from Pseudomonas fluorescens belong to a newly discovered sequence motif in flavoprotein hydroxylases with a putative dual function in FAD and NADPH binding [1]. To study their role in more detail, Phe161 and Arg166 were selectively changed by site-directed mutagenesis. F161A and F161G are catalytically competent enzymes having a rather poor affinity for NADPH. The catalytic properties of R166K are similar to those of the native enzyme. R166S and R166E show impaired NADPH binding and R166E has lost the ability to bind FAD. The crystal structure of substrate complexed F161A at 2.2 A is indistinguishable from the native enzyme, except for small changes at the site of mutation. The crystal structure of substrate complexed R166S at 2.0 A revealed that Arg166 is important for providing an intimate contact between the FAD binding domain and a long excursion of the substrate binding domain. It is proposed that this interaction is essential for structural stability and for the recognition of the pyrophosphate moiety of NADPH. (+info)Identification of 17-methyl-18-norandrosta-5,13(17-dien-3beta-ol, the C19 fragment formed by adrenal side chain cleavage of a 20-aryl analog of (20S)-20-hydroxycholesterol. (5/7757)
Incubation of (20R)-20-phenyl-5-pregnene-3beta,20-diol, an aromatic analog of (23S)-20-hydroxycholesterol, with an adrenal mitochondrial preparation leads to the formation of four compounds: pregnenolone, phenol, a C8 ketone, acetophenone, and a nonpolar C19 compound. This latter compound has now been identified by reverse isotope dilution analysis and by gas chromatography/mass spectrometry as 17-methyl-18-norandrosta-5,13(17)-dien-3beta-ol. From these results it is evident that enzymatic fission of the C-17,20 bond of this synthetic derivative occurs. On the other hand, when (20S)-20-hydroxy[21-14C]cholesterol was used as substrate, the analogous cleavage did not take place. Thus, substitution of an aromatic group on C-20 facilitates side chain cleavage between that carbon atom and the nucleus whereas neither of the naturally occuring precursors, cholesterol or its 20-hydroxylated counterpart, are metabolized to a C8 fragment. (+info)Relationship between supersaturation and calcium oxalate crystallization in normals and idiopathic calcium oxalate stone formers. (6/7757)
BACKGROUND: In an earlier study on recurrent CaOx stone formers with no detectable abnormalities, we found that the urine of these subjects had a lower tolerance to oxalate load than controls and that the removal of urinary macromolecules with a molecular weight greater than 10,000 D improved their tolerance to oxalate. METHODS: The effects on CaOx crystallization of reduced urinary supersaturation of calcium oxalate (CaOx), induced by night water load, were studied in 12 normal males and in 15 male OxCa stone formers who were free from urinary metabolic abnormalities. The effect of the macromolecules, purified and retrieved from the natural and diluted urine, were analyzed in a metastable solution of CaOx. RESULTS: The water load caused an increase in urine volume (from 307 +/- 111 to 572 +/- 322 ml/8 hr, P = 0.014 in normal subjects, and from 266 +/- 92 to 518 +/- 208 ml/8 hr, P = 0.001 in the stone formers) and a concomitant reduction of the relative CaOx supersaturation (from 8.7 +/- 2.5 to 5.1 +/- 2.5 ml/8 hr, P = 0.001 in normal subjects, and from 10.4 +/- 3.5 to 5.0 +/- 2.7 ml/8 hr, P = 0.001 in the stone formers). The decrease in CaOx supersaturation was accompanied by an increase of the permissible increment in oxalate, both in normal subjects (from 43.8 +/- 10.1 to 67.2 +/- 30. 3 mg/liter, P = 0.018) and in the stone formers (from 25.7 +/- 9.4 to 43.7 +/- 17.1 mg/liter, P = 0.0001), without any significant variations of the upper limit of metastability for CaOx (from 21.6 +/- 5.3 to 20.5 +/- 4.2 mg/liter in normal subjects, and from 18.7 +/- 4.5 to 17.1 +/- 3.7 mg/liter in the stone formers). The inhibitory effect of urinary macromolecules with molecular weight greater than 10,000 Daltons did not undergo any change when the latter were recovered from concentrated or diluted urine, either in normal subjects or in the stone formers. CONCLUSIONS: Reduced CaOx supersaturation by means of water load has a protective effect with regards to CaOx crystallization in subjects who do not present any of the common urinary stone risk factors. (+info)Cryoelectron microscopy of a nucleating model bile in vitreous ice: formation of primordial vesicles. (7/7757)
Because gallstones form so frequently in human bile, pathophysiologically relevant supersaturated model biles are commonly employed to study cholesterol crystal formation. We used cryo-transmission electron microscopy, complemented by polarizing light microscopy, to investigate early stages of cholesterol nucleation in model bile. In the system studied, the proposed microscopic sequence involves the evolution of small unilamellar to multilamellar vesicles to lamellar liquid crystals and finally to cholesterol crystals. Small aliquots of a concentrated (total lipid concentration = 29.2 g/dl) model bile containing 8.5% cholesterol, 22.9% egg yolk lecithin, and 68.6% taurocholate (all mole %) were vitrified at 2 min to 20 days after fourfold dilution to induce supersaturation. Mixed micelles together with a category of vesicles denoted primordial, small unilamellar vesicles of two distinct morphologies (sphere/ellipsoid and cylinder/arachoid), large unilamellar vesicles, multilamellar vesicles, and cholesterol monohydrate crystals were imaged. No evidence of aggregation/fusion of small unilamellar vesicles to form multilamellar vesicles was detected. Low numbers of multilamellar vesicles were present, some of which were sufficiently large to be identified as liquid crystals by polarizing light microscopy. Dimensions, surface areas, and volumes of spherical/ellipsoidal and cylindrical/arachoidal vesicles were quantified. Early stages in the separation of vesicles from micelles, referred to as primordial vesicles, were imaged 23-31 min after dilution. Observed structures such as enlarged micelles in primordial vesicle interiors, segments of bilayer, and faceted edges at primordial vesicle peripheries are probably early stages of small unilamellar vesicle assembly. A decrease in the mean surface area of spherical/ellipsoidal vesicles was correlated with the increased production of cholesterol crystals at 10-20 days after supersaturation by dilution, supporting the role of small unilamellar vesicles as key players in cholesterol nucleation and as cholesterol donors to crystals. This is the first visualization of an intermediate structure that has been temporally linked to the development of small unilamellar vesicles in the separation of vesicles from micelles in a model bile and suggests a time-resolved system for further investigation. (+info)Purification and properties of a low-molecular-weight, high-alkaline pectate lyase from an alkaliphilic strain of Bacillus. (8/7757)
A low-molecular-weight, high-alkaline pectate lyase (pectate transeliminase, EC 4.2.2.2) was found in an alkaline culture of Bacillus sp. strain KSM-P15, purified to homogeneity, and crystallized. The enzyme had a relative molecular weight of approximately 20,300 as measured by sedimentation equilibrium, with a sedimentation coefficient (s20,w0) of 1.73 S. It was a basic protein with an isoelectric point of pH 10.3, and the alpha-helical content was only 6.6%. In the presence of Ca2+ ions, the enzyme degraded polygalacturonic acid in a random manner to yield 4,5-unsaturated oligo-galacturonides and had its optimal activity around pH 10.5 and 50-55 degrees C. It also had a protopectinase-like activity on cotton fibers. The N-terminal amino acid sequences of the intact protein (28 amino acids) and its two lysyl endopeptidase-cleaved peptide fragments (8 and 12 amino acids) had very low sequence similarity with pectate lyases reported to date. These results strongly suggest that the pectate lyase of Bacillus sp. strain KSM-P15 may be a novel enzyme and belongs in a new family. (+info)Crystallization is a process in which a substance transitions from a liquid or dissolved state to a solid state, forming a crystal lattice. In the medical context, crystallization can refer to the formation of crystals within the body, which can occur under certain conditions such as changes in pH, temperature, or concentration of solutes. These crystals can deposit in various tissues and organs, leading to the formation of crystal-induced diseases or disorders.
For example, in patients with gout, uric acid crystals can accumulate in joints, causing inflammation, pain, and swelling. Similarly, in nephrolithiasis (kidney stones), minerals in the urine can crystallize and form stones that can obstruct the urinary tract. Crystallization can also occur in other medical contexts, such as in the formation of dental calculus or plaque, and in the development of cataracts in the eye.
X-ray crystallography is a technique used in structural biology to determine the three-dimensional arrangement of atoms in a crystal lattice. In this method, a beam of X-rays is directed at a crystal and diffracts, or spreads out, into a pattern of spots called reflections. The intensity and angle of each reflection are measured and used to create an electron density map, which reveals the position and type of atoms in the crystal. This information can be used to determine the molecular structure of a compound, including its shape, size, and chemical bonds. X-ray crystallography is a powerful tool for understanding the structure and function of biological macromolecules such as proteins and nucleic acids.
X-ray diffraction (XRD) is not strictly a medical definition, but it is a technique commonly used in the field of medical research and diagnostics. XRD is a form of analytical spectroscopy that uses the phenomenon of X-ray diffraction to investigate the crystallographic structure of materials. When a beam of X-rays strikes a crystal, it is scattered in specific directions and with specific intensities that are determined by the arrangement of atoms within the crystal. By measuring these diffraction patterns, researchers can determine the crystal structures of various materials, including biological macromolecules such as proteins and viruses.
In the medical field, XRD is often used to study the structure of drugs and drug candidates, as well as to analyze the composition and structure of tissues and other biological samples. For example, XRD can be used to investigate the crystal structures of calcium phosphate minerals in bone tissue, which can provide insights into the mechanisms of bone formation and disease. Additionally, XRD is sometimes used in the development of new medical imaging techniques, such as phase-contrast X-ray imaging, which has the potential to improve the resolution and contrast of traditional X-ray images.
Crystallography is a branch of science that deals with the geometric properties, internal arrangement, and formation of crystals. It involves the study of the arrangement of atoms, molecules, or ions in a crystal lattice and the physical properties that result from this arrangement. Crystallographers use techniques such as X-ray diffraction to determine the structure of crystals at the atomic level. This information is important for understanding the properties of various materials and can be used in fields such as materials science, chemistry, and biology.
Selenomethionine is an organic form of selenium, which is an essential trace element in human nutrition. It is incorporated into proteins in place of methionine, one of the 20 standard amino acids, and functions as an antioxidant by helping to prevent cellular damage from free radicals. Selenomethionine can be found in a variety of foods, including brazil nuts, fish, meat, and whole grains, and is also available as a dietary supplement.
Protein conformation refers to the specific three-dimensional shape that a protein molecule assumes due to the spatial arrangement of its constituent amino acid residues and their associated chemical groups. This complex structure is determined by several factors, including covalent bonds (disulfide bridges), hydrogen bonds, van der Waals forces, and ionic bonds, which help stabilize the protein's unique conformation.
Protein conformations can be broadly classified into two categories: primary, secondary, tertiary, and quaternary structures. The primary structure represents the linear sequence of amino acids in a polypeptide chain. The secondary structure arises from local interactions between adjacent amino acid residues, leading to the formation of recurring motifs such as α-helices and β-sheets. Tertiary structure refers to the overall three-dimensional folding pattern of a single polypeptide chain, while quaternary structure describes the spatial arrangement of multiple folded polypeptide chains (subunits) that interact to form a functional protein complex.
Understanding protein conformation is crucial for elucidating protein function, as the specific three-dimensional shape of a protein directly influences its ability to interact with other molecules, such as ligands, nucleic acids, or other proteins. Any alterations in protein conformation due to genetic mutations, environmental factors, or chemical modifications can lead to loss of function, misfolding, aggregation, and disease states like neurodegenerative disorders and cancer.
A synchrotron is not a medical term, but rather a type of particle accelerator used in physics and related fields. Therefore, it doesn't have a specific medical definition. However, synchrotrons do have important applications in medicine, particularly in the field of medical imaging and radiation therapy.
In brief, a synchrotron is a large circular accelerator that uses magnetic fields to bend and focus a beam of charged particles (such as electrons) into a narrow, intense beam. The particles are then accelerated to very high speeds using electric fields. As the particles pass through special devices called insertion devices, they emit light in the form of X-rays or other forms of electromagnetic radiation. These X-rays can be used for a variety of scientific and medical applications, including:
1. Medical imaging: Synchrotron X-rays can produce high-resolution images of the body's internal structures, such as bones, tissues, and organs. This is particularly useful in the study of complex anatomical structures or diseases that affect them.
2. Radiation therapy: Synchrotron radiation can be used to deliver highly targeted doses of radiation to cancer cells while minimizing damage to surrounding healthy tissue. This technique, known as synchrotron-based radiotherapy, is still in the experimental stage but shows promise for improving the effectiveness and safety of radiation therapy.
3. Biomedical research: Synchrotron X-rays can be used to study the structure and function of biological molecules, such as proteins and DNA, at a molecular level. This information can help researchers better understand the mechanisms of diseases and develop new drugs and therapies.
In summary, while synchrotrons are not medical terms themselves, they have important applications in medicine, particularly in medical imaging, radiation therapy, and biomedical research.
Bacterial proteins are a type of protein that are produced by bacteria as part of their structural or functional components. These proteins can be involved in various cellular processes, such as metabolism, DNA replication, transcription, and translation. They can also play a role in bacterial pathogenesis, helping the bacteria to evade the host's immune system, acquire nutrients, and multiply within the host.
Bacterial proteins can be classified into different categories based on their function, such as:
1. Enzymes: Proteins that catalyze chemical reactions in the bacterial cell.
2. Structural proteins: Proteins that provide structural support and maintain the shape of the bacterial cell.
3. Signaling proteins: Proteins that help bacteria to communicate with each other and coordinate their behavior.
4. Transport proteins: Proteins that facilitate the movement of molecules across the bacterial cell membrane.
5. Toxins: Proteins that are produced by pathogenic bacteria to damage host cells and promote infection.
6. Surface proteins: Proteins that are located on the surface of the bacterial cell and interact with the environment or host cells.
Understanding the structure and function of bacterial proteins is important for developing new antibiotics, vaccines, and other therapeutic strategies to combat bacterial infections.
Calcium oxalate is a chemical compound with the formula CaC2O4. It is the most common type of stone found in kidneys, also known as kidney stones. Calcium oxalate forms when there is too much calcium or oxalate in the urine. This can occur due to various reasons such as dietary habits, dehydration, medical conditions like hyperparathyroidism, or genetic factors.
Calcium oxalate stones are hard and crystalline and can cause severe pain during urination or while passing through the urinary tract. They may also lead to other symptoms like blood in the urine, nausea, vomiting, or fever. Prevention strategies for calcium oxalate stones include staying hydrated, following a balanced diet, and taking prescribed medications to control the levels of calcium and oxalate in the body.
Molecular cloning is a laboratory technique used to create multiple copies of a specific DNA sequence. This process involves several steps:
1. Isolation: The first step in molecular cloning is to isolate the DNA sequence of interest from the rest of the genomic DNA. This can be done using various methods such as PCR (polymerase chain reaction), restriction enzymes, or hybridization.
2. Vector construction: Once the DNA sequence of interest has been isolated, it must be inserted into a vector, which is a small circular DNA molecule that can replicate independently in a host cell. Common vectors used in molecular cloning include plasmids and phages.
3. Transformation: The constructed vector is then introduced into a host cell, usually a bacterial or yeast cell, through a process called transformation. This can be done using various methods such as electroporation or chemical transformation.
4. Selection: After transformation, the host cells are grown in selective media that allow only those cells containing the vector to grow. This ensures that the DNA sequence of interest has been successfully cloned into the vector.
5. Amplification: Once the host cells have been selected, they can be grown in large quantities to amplify the number of copies of the cloned DNA sequence.
Molecular cloning is a powerful tool in molecular biology and has numerous applications, including the production of recombinant proteins, gene therapy, functional analysis of genes, and genetic engineering.
'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.
Recombinant proteins are artificially created proteins produced through the use of recombinant DNA technology. This process involves combining DNA molecules from different sources to create a new set of genes that encode for a specific protein. The resulting recombinant protein can then be expressed, purified, and used for various applications in research, medicine, and industry.
Recombinant proteins are widely used in biomedical research to study protein function, structure, and interactions. They are also used in the development of diagnostic tests, vaccines, and therapeutic drugs. For example, recombinant insulin is a common treatment for diabetes, while recombinant human growth hormone is used to treat growth disorders.
The production of recombinant proteins typically involves the use of host cells, such as bacteria, yeast, or mammalian cells, which are engineered to express the desired protein. The host cells are transformed with a plasmid vector containing the gene of interest, along with regulatory elements that control its expression. Once the host cells are cultured and the protein is expressed, it can be purified using various chromatography techniques.
Overall, recombinant proteins have revolutionized many areas of biology and medicine, enabling researchers to study and manipulate proteins in ways that were previously impossible.
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.
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.
Hemoglobin C is a type of hemoglobin variant, which is the oxygen-carrying protein in red blood cells. Hemoglobin C is caused by a specific genetic mutation that results in the substitution of lysine for glutamic acid at position 6 on the beta globin chain of the hemoglobin molecule.
This variant is often associated with a benign condition known as hemoglobin C trait, where an individual inherits one copy of the mutated gene from one parent and one normal gene from the other parent. People with this trait usually have no symptoms or only mild anemia, if any. However, if an individual inherits two copies of the Hemoglobin C gene (one from each parent), they will have a more severe form of hemoglobin disorder called Hemoglobin CC disease, which can cause mild to moderate hemolytic anemia and other complications.
It's important to note that Hemoglobin C is most commonly found in people of West African descent, but it can also occur in other populations with African ancestry.
Tertiary protein structure refers to the three-dimensional arrangement of all the elements (polypeptide chains) of a single protein molecule. It is the highest level of structural organization and results from interactions between various side chains (R groups) of the amino acids that make up the protein. These interactions, which include hydrogen bonds, ionic bonds, van der Waals forces, and disulfide bridges, give the protein its unique shape and stability, which in turn determines its function. The tertiary structure of a protein can be stabilized by various factors such as temperature, pH, and the presence of certain ions. Any changes in these factors can lead to denaturation, where the protein loses its tertiary structure and thus its function.
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.
Muramidase, also known as lysozyme, is an enzyme that hydrolyzes the glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine in peptidoglycan, a polymer found in bacterial cell walls. This enzymatic activity plays a crucial role in the innate immune system by contributing to the destruction of invading bacteria. Muramidase is widely distributed in various tissues and bodily fluids, such as tears, saliva, and milk, and is also found in several types of white blood cells, including neutrophils and monocytes.
I apologize for any confusion, but "Pyrococcus horikoshii" is not a medical term or concept. It is actually the name of a species of archaea, which are single-celled microorganisms that share some characteristics with both bacteria and eukaryotes (complex cells like those found in animals, plants, and fungi).
"Pyrococcus horikoshii" is particularly notable for its ability to thrive in extremely high temperature environments, with an optimum growth temperature of around 100 degrees Celsius. It was first isolated from a marine volcanic hot spring near Kuroshio, Japan. This organism has been studied extensively in the field of molecular biology and genetics due to its unique properties and potential applications in biotechnology.
Volatilization, in the context of pharmacology and medicine, refers to the process by which a substance (usually a medication or drug) transforms into a vapor state at room temperature or upon heating. This change in physical state allows the substance to evaporate and be transferred into the air, potentially leading to inhalation exposure.
In some medical applications, volatilization is used intentionally, such as with essential oils for aromatherapy or topical treatments that utilize a vapor action. However, it can also pose concerns when volatile substances are unintentionally released into the air, potentially leading to indoor air quality issues or exposure risks.
It's important to note that in clinical settings, volatilization is not typically used as a route of administration for medications, as other methods such as oral, intravenous, or inhalation via nebulizers are more common and controlled.
Detergents are cleaning agents that are often used to remove dirt, grease, and stains from various surfaces. They contain one or more surfactants, which are compounds that lower the surface tension between two substances, such as water and oil, allowing them to mix more easily. This makes it possible for detergents to lift and suspend dirt particles in water so they can be rinsed away.
Detergents may also contain other ingredients, such as builders, which help to enhance the cleaning power of the surfactants by softening hard water or removing mineral deposits. Some detergents may also include fragrances, colorants, and other additives to improve their appearance or performance.
In a medical context, detergents are sometimes used as disinfectants or antiseptics, as they can help to kill bacteria, viruses, and other microorganisms on surfaces. However, it is important to note that not all detergents are effective against all types of microorganisms, and some may even be toxic or harmful if used improperly.
It is always important to follow the manufacturer's instructions when using any cleaning product, including detergents, to ensure that they are used safely and effectively.
Solubility is a fundamental concept in pharmaceutical sciences and medicine, which refers to the maximum amount of a substance (solute) that can be dissolved in a given quantity of solvent (usually water) at a specific temperature and pressure. Solubility is typically expressed as mass of solute per volume or mass of solvent (e.g., grams per liter, milligrams per milliliter). The process of dissolving a solute in a solvent results in a homogeneous solution where the solute particles are dispersed uniformly throughout the solvent.
Understanding the solubility of drugs is crucial for their formulation, administration, and therapeutic effectiveness. Drugs with low solubility may not dissolve sufficiently to produce the desired pharmacological effect, while those with high solubility might lead to rapid absorption and short duration of action. Therefore, optimizing drug solubility through various techniques like particle size reduction, salt formation, or solubilization is an essential aspect of drug development and delivery.
Electrophoresis, polyacrylamide gel (EPG) is a laboratory technique used to separate and analyze complex mixtures of proteins or nucleic acids (DNA or RNA) based on their size and electrical charge. This technique utilizes a matrix made of cross-linked polyacrylamide, a type of gel, which provides a stable and uniform environment for the separation of molecules.
In this process:
1. The polyacrylamide gel is prepared by mixing acrylamide monomers with a cross-linking agent (bis-acrylamide) and a catalyst (ammonium persulfate) in the presence of a buffer solution.
2. The gel is then poured into a mold and allowed to polymerize, forming a solid matrix with uniform pore sizes that depend on the concentration of acrylamide used. Higher concentrations result in smaller pores, providing better resolution for separating smaller molecules.
3. Once the gel has set, it is placed in an electrophoresis apparatus containing a buffer solution. Samples containing the mixture of proteins or nucleic acids are loaded into wells on the top of the gel.
4. An electric field is applied across the gel, causing the negatively charged molecules to migrate towards the positive electrode (anode) while positively charged molecules move toward the negative electrode (cathode). The rate of migration depends on the size, charge, and shape of the molecules.
5. Smaller molecules move faster through the gel matrix and will migrate farther from the origin compared to larger molecules, resulting in separation based on size. Proteins and nucleic acids can be selectively stained after electrophoresis to visualize the separated bands.
EPG is widely used in various research fields, including molecular biology, genetics, proteomics, and forensic science, for applications such as protein characterization, DNA fragment analysis, cloning, mutation detection, and quality control of nucleic acid or protein samples.
In the context of medical terminology, "solutions" refers to a homogeneous mixture of two or more substances, in which one substance (the solute) is uniformly distributed within another substance (the solvent). The solvent is typically the greater component of the solution and is capable of dissolving the solute.
Solutions can be classified based on the physical state of the solvent and solute. For instance, a solution in which both the solvent and solute are liquids is called a liquid solution or simply a solution. A solid solution is one where the solvent is a solid and the solute is either a gas, liquid, or solid. Similarly, a gas solution refers to a mixture where the solvent is a gas and the solute can be a gas, liquid, or solid.
In medical applications, solutions are often used as vehicles for administering medications, such as intravenous (IV) fluids, oral rehydration solutions, eye drops, and topical creams or ointments. The composition of these solutions is carefully controlled to ensure the appropriate concentration and delivery of the active ingredients.
Temperature, in a medical context, is a measure of the degree of hotness or coldness of a body or environment. It is usually measured using a thermometer and reported in degrees Celsius (°C), degrees Fahrenheit (°F), or kelvin (K). In the human body, normal core temperature ranges from about 36.5-37.5°C (97.7-99.5°F) when measured rectally, and can vary slightly depending on factors such as time of day, physical activity, and menstrual cycle. Elevated body temperature is a common sign of infection or inflammation, while abnormally low body temperature can indicate hypothermia or other medical conditions.
'Thermus thermophilus' is not a medical term, but a scientific name for a species of bacteria. It is commonly used in molecular biology and genetics research. Here is the biological definition:
'Thermus thermophilus' is a gram-negative, rod-shaped, thermophilic bacterium found in hot springs and other high-temperature environments. Its optimum growth temperature ranges from 65 to 70°C (149-158°F), with some strains able to grow at temperatures as high as 85°C (185°F). The bacterium's DNA polymerase enzyme, Taq polymerase, is widely used in the Polymerase Chain Reaction (PCR) technique for amplifying and analyzing DNA. 'Thermus thermophilus' has a single circular chromosome and can also have one or more plasmids. Its genome has been fully sequenced, making it an important model organism for studying extremophiles and their adaptations to harsh environments.
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks and in the shells of many marine animals. As a mineral, it is known as calcite or aragonite.
In the medical field, calcium carbonate is often used as a dietary supplement to prevent or treat calcium deficiency. It is also commonly used as an antacid to neutralize stomach acid and relieve symptoms of heartburn, acid reflux, and indigestion.
Calcium carbonate works by reacting with hydrochloric acid in the stomach to form water, carbon dioxide, and calcium chloride. This reaction helps to raise the pH level in the stomach and neutralize excess acid.
It is important to note that excessive use of calcium carbonate can lead to hypercalcemia, a condition characterized by high levels of calcium in the blood, which can cause symptoms such as nausea, vomiting, constipation, confusion, and muscle weakness. Therefore, it is recommended to consult with a healthcare provider before starting any new supplement regimen.
Archaeal proteins are proteins that are encoded by the genes found in archaea, a domain of single-celled microorganisms. These proteins are crucial for various cellular functions and structures in archaea, which are adapted to survive in extreme environments such as high temperatures, high salt concentrations, and low pH levels.
Archaeal proteins share similarities with both bacterial and eukaryotic proteins, but they also have unique features that distinguish them from each other. For example, many archaeal proteins contain unusual amino acids or modifications that are not commonly found in other organisms. Additionally, the three-dimensional structures of some archaeal proteins are distinct from their bacterial and eukaryotic counterparts.
Studying archaeal proteins is important for understanding the biology of these unique organisms and for gaining insights into the evolution of life on Earth. Furthermore, because some archaea can survive in extreme environments, their proteins may have properties that make them useful in industrial and medical applications.
Proteins are complex, large molecules that play critical roles in the body's functions. They are made up of amino acids, which are organic compounds that are the building blocks of proteins. Proteins are required for the structure, function, and regulation of the body's tissues and organs. They are essential for the growth, repair, and maintenance of body tissues, and they play a crucial role in many biological processes, including metabolism, immune response, and cellular signaling. Proteins can be classified into different types based on their structure and function, such as enzymes, hormones, antibodies, and structural proteins. They are found in various foods, especially animal-derived products like meat, dairy, and eggs, as well as plant-based sources like beans, nuts, and grains.
Differential Thermal Analysis (DTA) is a technique used in thermoanalysis to study the physical and chemical changes that occur in a material as it is heated or cooled. It measures the difference in temperature between a sample and a reference material, both of which are subjected to the same temperature program.
In DTA, the sample and reference material are placed in separate but identical holders, and the temperature of the reference material is kept constant while the temperature of the sample is increased or decreased at a controlled rate. As the sample undergoes physical or chemical changes, such as phase transitions or chemical reactions, it absorbs or releases heat, causing its temperature to change relative to the reference material.
The DTA curve plots the temperature difference between the sample and the reference material against time or temperature. The resulting curve provides information about the thermal behavior of the sample, including any endothermic or exothermic reactions that occur as it is heated or cooled. Endothermic reactions, which require heat input, are indicated by a negative deflection in the DTA curve, while exothermic reactions, which release heat, are indicated by a positive deflection.
DTA is widely used in materials science, chemistry, and physics to study the thermal properties of materials, including their phase transitions, melting points, crystallization behavior, and chemical stability. It can also be used to identify unknown materials or to characterize the purity of a sample.
Chemical precipitation is a process in which a chemical compound becomes a solid, insoluble form, known as a precipitate, from a liquid solution. This occurs when the concentration of the compound in the solution exceeds its solubility limit and forms a separate phase. The reaction that causes the formation of the precipitate can be a result of various factors such as changes in temperature, pH, or the addition of another chemical reagent.
In the medical field, chemical precipitation is used in diagnostic tests to detect and measure the presence of certain substances in body fluids, such as blood or urine. For example, a common test for kidney function involves adding a chemical reagent to a urine sample, which causes the excess protein in the urine to precipitate out of solution. The amount of precipitate formed can then be measured and used to diagnose and monitor kidney disease.
Chemical precipitation is also used in the treatment of certain medical conditions, such as heavy metal poisoning. In this case, a chelating agent is administered to bind with the toxic metal ions in the body, forming an insoluble compound that can be excreted through the urine or feces. This process helps to reduce the amount of toxic metals in the body and alleviate symptoms associated with poisoning.
Polyethylene glycols (PEGs) are a family of synthetic, water-soluble polymers with a wide range of molecular weights. They are commonly used in the medical field as excipients in pharmaceutical formulations due to their ability to improve drug solubility, stability, and bioavailability. PEGs can also be used as laxatives to treat constipation or as bowel cleansing agents prior to colonoscopy examinations. Additionally, some PEG-conjugated drugs have been developed for use in targeted cancer therapies.
In a medical context, PEGs are often referred to by their average molecular weight, such as PEG 300, PEG 400, PEG 1500, and so on. Higher molecular weight PEGs tend to be more viscous and have longer-lasting effects in the body.
It's worth noting that while PEGs are generally considered safe for use in medical applications, some people may experience allergic reactions or hypersensitivity to these compounds. Prolonged exposure to high molecular weight PEGs has also been linked to potential adverse effects, such as decreased fertility and developmental toxicity in animal studies. However, more research is needed to fully understand the long-term safety of PEGs in humans.
Urinary calculi, also known as kidney stones or nephrolithiasis, are hard deposits made of minerals and salts that form inside the urinary system. These calculi can develop in any part of the urinary system, which includes the kidneys, ureters, bladder, and urethra.
The formation of urinary calculi typically occurs when there is a concentration of certain substances, such as calcium, oxalate, uric acid, or struvite, in the urine. When these substances become highly concentrated, they can crystallize and form small seeds that gradually grow into larger stones over time.
The size of urinary calculi can vary from tiny, sand-like particles to large stones that can fill the entire renal pelvis. The symptoms associated with urinary calculi depend on the stone's size, location, and whether it is causing a blockage in the urinary tract. Common symptoms include severe pain in the flank, lower abdomen, or groin; nausea and vomiting; blood in the urine (hematuria); fever and chills; and frequent urge to urinate or painful urination.
Treatment for urinary calculi depends on the size and location of the stone, as well as the severity of symptoms. Small stones may pass spontaneously with increased fluid intake and pain management. Larger stones may require medical intervention, such as extracorporeal shock wave lithotripsy (ESWL), ureteroscopy, or percutaneous nephrolithotomy (PCNL) to break up or remove the stone. Preventive measures include maintaining adequate hydration, modifying dietary habits, and taking medications to reduce the risk of stone formation.
'Archaeoglobus fulgidus' is a species of archaea, which are single-celled microorganisms that share some characteristics with bacteria but are genetically and biochemically distinct. This particular species is extremophilic, meaning it thrives in extreme environments that are hostile to most other life forms.
'Archaeoglobus fulgidus' is found in deep-sea hydrothermal vents and oil reservoirs, where it exists under high temperatures (up to 92°C) and high pressures. It is a sulfate-reducing organism, which means it obtains energy by reducing sulfates to hydrogen sulfide, using organic compounds as electron donors. This process plays a significant role in the global sulfur cycle and the anaerobic degradation of organic matter in extreme environments.
The study of 'Archaeoglobus fulgidus' and other archaea has provided valuable insights into the evolution and diversity of life on Earth, as well as the biochemical adaptations that allow organisms to survive under extreme conditions.
Kidney calculi, also known as kidney stones, are hard deposits made of minerals and salts that form inside your kidneys. They can range in size from a grain of sand to a golf ball. When they're small enough, they can be passed through your urine without causing too much discomfort. However, larger stones may block the flow of urine, causing severe pain and potentially leading to serious complications such as urinary tract infections or kidney damage if left untreated.
The formation of kidney calculi is often associated with factors like dehydration, high levels of certain minerals in your urine, family history, obesity, and certain medical conditions such as gout or inflammatory bowel disease. Symptoms of kidney stones typically include severe pain in the back, side, lower abdomen, or groin; nausea and vomiting; fever and chills if an infection is present; and blood in the urine. Treatment options depend on the size and location of the stone but may include medications to help pass the stone, shock wave lithotripsy to break up the stone, or surgical removal of the stone in severe cases.
Gel chromatography is a type of liquid chromatography that separates molecules based on their size or molecular weight. It uses a stationary phase that consists of a gel matrix made up of cross-linked polymers, such as dextran, agarose, or polyacrylamide. The gel matrix contains pores of various sizes, which allow smaller molecules to penetrate deeper into the matrix while larger molecules are excluded.
In gel chromatography, a mixture of molecules is loaded onto the top of the gel column and eluted with a solvent that moves down the column by gravity or pressure. As the sample components move down the column, they interact with the gel matrix and get separated based on their size. Smaller molecules can enter the pores of the gel and take longer to elute, while larger molecules are excluded from the pores and elute more quickly.
Gel chromatography is commonly used to separate and purify proteins, nucleic acids, and other biomolecules based on their size and molecular weight. It is also used in the analysis of polymers, colloids, and other materials with a wide range of applications in chemistry, biology, and medicine.
Methanococcaceae is a family of archaea within the order Methanococcales. These are obligate anaerobic, methanogenic microorganisms that are commonly found in marine and freshwater environments. They can also be found in association with animals, including humans, where they may play a role in digestion. Members of this family are characterized by their ability to produce methane as a metabolic end-product using hydrogen and carbon dioxide as substrates. Some notable genera within this family include Methanococcus, Methanothermococcus, and Methanocaldococcus.
Aldose-ketose isomerases are a group of enzymes that catalyze the interconversion between aldoses and ketoses, which are different forms of sugars. These enzymes play an essential role in carbohydrate metabolism by facilitating the reversible conversion of aldoses to ketoses and vice versa.
Aldoses are sugars that contain a carbonyl group (a functional group consisting of a carbon atom double-bonded to an oxygen atom) at the end of the carbon chain, while ketoses have their carbonyl group located in the middle of the chain. The isomerization process catalyzed by aldose-ketose isomerases helps maintain the balance between these two forms of sugars and enables cells to utilize them more efficiently for energy production and other metabolic processes.
There are several types of aldose-ketose isomerases, including:
1. Triose phosphate isomerase (TPI): This enzyme catalyzes the interconversion between dihydroxyacetone phosphate (a ketose) and D-glyceraldehyde 3-phosphate (an aldose), which are both trioses (three-carbon sugars). TPI plays a crucial role in glycolysis, the metabolic pathway that breaks down glucose to produce energy.
2. Xylulose kinase: This enzyme is involved in the pentose phosphate pathway, which is a metabolic route that generates reducing equivalents (NADPH) and pentoses for nucleic acid synthesis. Xylulose kinase catalyzes the conversion of D-xylulose (a ketose) to D-xylulose 5-phosphate, an important intermediate in the pentose phosphate pathway.
3. Ribulose-5-phosphate 3-epimerase: This enzyme is also part of the pentose phosphate pathway and catalyzes the interconversion between D-ribulose 5-phosphate (an aldose) and D-xylulose 5-phosphate (a ketose).
4. Phosphoglucomutase: This enzyme catalyzes the reversible conversion of glucose 1-phosphate (an aldose) to glucose 6-phosphate (an aldose), which is an important intermediate in both glycolysis and gluconeogenesis.
5. Phosphomannomutase: This enzyme catalyzes the reversible conversion of mannose 1-phosphate (a ketose) to mannose 6-phosphate (an aldose), which is involved in the biosynthesis of complex carbohydrates.
These are just a few examples of enzymes that catalyze the interconversion between aldoses and ketoses, highlighting their importance in various metabolic pathways.
Radiation scattering is a physical process in which radiation particles or waves deviate from their original direction due to interaction with matter. This phenomenon can occur through various mechanisms such as:
1. Elastic Scattering: Also known as Thomson scattering or Rayleigh scattering, it occurs when the energy of the scattered particle or wave remains unchanged after the collision. In the case of electromagnetic radiation (e.g., light), this results in a change of direction without any loss of energy.
2. Inelastic Scattering: This type of scattering involves an exchange of energy between the scattered particle and the target medium, leading to a change in both direction and energy of the scattered particle or wave. An example is Compton scattering, where high-energy photons (e.g., X-rays or gamma rays) interact with charged particles (usually electrons), resulting in a decrease in photon energy and an increase in electron kinetic energy.
3. Coherent Scattering: In this process, the scattered radiation maintains its phase relationship with the incident radiation, leading to constructive and destructive interference patterns. An example is Bragg scattering, which occurs when X-rays interact with a crystal lattice, resulting in diffraction patterns that reveal information about the crystal structure.
In medical contexts, radiation scattering can have both beneficial and harmful effects. For instance, in diagnostic imaging techniques like computed tomography (CT) scans, radiation scattering contributes to image noise and reduces contrast resolution. However, in radiation therapy for cancer treatment, controlled scattering of therapeutic radiation beams can help ensure that the tumor receives a uniform dose while minimizing exposure to healthy tissues.
Quaternary protein structure refers to the arrangement and interaction of multiple folded protein molecules in a multi-subunit complex. These subunits can be identical or different forms of the same protein or distinctly different proteins that associate to form a functional complex. The quaternary structure is held together by non-covalent interactions, such as hydrogen bonds, ionic bonds, and van der Waals forces. Understanding quaternary structure is crucial for comprehending the function, regulation, and assembly of many protein complexes involved in various cellular processes.
"Bothrops" is a genus of venomous snakes commonly known as lancehead vipers, found primarily in Central and South America. The name "Bothrops" comes from the Greek words "bothros," meaning pit, and "ops," meaning face, referring to the deep pits on the sides of their heads that help them detect heat and locate prey. These snakes are known for their aggressive behavior and potent venom, which can cause severe pain, swelling, tissue damage, and potentially life-threatening systemic effects if left untreated.
The genus "Bothrops" includes over 30 species of pit vipers, many of which are considered medically important due to their ability to inflict serious envenomations in humans. Some notable examples include Bothrops asper (the terciopelo or fer-de-lance), Bothrops atrox (the common lancehead), and Bothrops jararaca (the jararaca).
If you encounter a snake of this genus, it is essential to seek medical attention immediately if bitten, as the venom can cause significant harm if not treated promptly.
Negative staining is a histological or microscopy technique used to enhance the contrast of transparent or translucent specimens, such as bacteria and viruses. This technique involves applying a thin layer of a dense, dark-staining material (such as a heavy metal salt) onto the surface of the sample. The stain does not penetrate the specimen but rather forms a thin layer around it, creating a "negative" image where the specimen appears lighter against the dark background. This method is particularly useful for visualizing the shape and structure of small or delicate biological samples that would be difficult to see using other staining techniques.
Diffusion, in the context of medicine and physiology, refers to the process by which molecules move from an area of high concentration to an area of low concentration until they are evenly distributed throughout a space or solution. This passive transport mechanism does not require energy and relies solely on the random motion of particles. Diffusion is a vital process in many biological systems, including the exchange of gases in the lungs, the movement of nutrients and waste products across cell membranes, and the spread of drugs and other substances throughout tissues.
Crystallization
Crystallization (love)
Strain crystallization
Crystallization (disambiguation)
Adolescent crystallization
Crystallization adjutant
Fractional crystallization
Protein crystallization
Fractional crystallization (geology)
Fractional crystallization (chemistry)
Metal-induced crystallization
Crystallization of polymers
Water of crystallization
Urea extraction crystallization
International Organization for Biological Crystallization
PreQ1 synthase
Social norm
Sodium nitrate
Alan Neville Gent
Arab Potash
Mineral evolution
Selenomethionine
Supersaturation
Zero liquid discharge
Nucleation
Canavalin
Cytochrome c
Ergothioneine
Turnip yellow mosaic virus
L-lactate dehydrogenase (cytochrome)
Crystallization - Wikipedia
Crystallization (love) - Wikipedia
Crystallization and Evaporation | AIChE
Rotigotine Patch Recalled Due to Drug Crystallization
Glass crystallization making red phosphor for | EurekAlert!
Crystallization - New World Encyclopedia
NetLogo Models Library: Crystallization Directed
Biomolecular Crystallisation and Characterisation (BCC) - CSIRO
Protein Crystallization | Create Lattices
Crystallization and Crystallizers - ISTE
Protein Crystallization Experiment in Space for Improved Patient Care - Bristol Myers Squibb
Yttria-stabilized zirconia crystallization in Al2O3/YSZ multilayers | Journal of Materials Research | Cambridge Core
Crystallization of prostaglandin-H synthase for X-ray structure analysis.
Peptoids help to uncover different crystallization pathways - Materials Today
Advanced methods in macromolecular crystallization X - FEBS
Crystallization of the Past Masters -- Part 1
Crystallisation of caesium borosilicate glasses with approximate boroleucite composition
IUCr) Crystallization and diffraction analysis of the SARS coronavirus nsp10-nsp16 complex
DME-driven fractional crystallization: 2023 R&D 100 Award | Ames Laboratory
Crystallisation inhibitor | IMCD
Protein Crystallization Scientist job with Virginia Commonwealth University | 37331474
Session: PAT for Crystallization Development and Manufacturing (2014 Annual Meeting)
APS -APS March Meeting 2020 - Event - Flow-Induced Crystallization of Polymers during Multi-Axial Deformation
Alaska Volcano Observatory - Geothermometry and cathodluminescence of quartz reveal crystallization histories of Katmai magmas
Characterizing the Impact of Shear Induced Crystallization on a Polymer Melt | Anton Paar
Examining the crystallisation during additive biomanufacturing - - Diamond Light Source
International Symposium on Industrial Crystallization (ISIC) 2008
SNF472, a novel anti-crystallization agent, inhibits induced calcification in an in vitro model of human aortic valve...
Crystallization | Biomolecular X-ray Crystallography Facility | University of Colorado Boulder
3.6A: Single Solvent Crystallization - Chemistry LibreTexts
Biophysical2
- The ideal candidate will have a strong background in medicinal chemistry, and/or protein crystallization, and biophysical/biochemical characterization. (chronicle.com)
- At the LP3 crystallisation and biophysical laboratory, you can carry out a wide variety of robot-assisted crystallisation experiments in nano volumes as well as screen for a large number of buffer conditions to stabilize their sample. (lu.se)
Processes5
- The session is focused on providing examples where Process Analytical Technologies (PAT) have been used in the development and control of crystallization processes. (confex.com)
- Crystallisation processes have evolved to practical methods that allow isolation of an enantiopure product in high yield. (strath.ac.uk)
- This tutorial review covers the basic principles behind asymmetric crystallisation processes, with an emphasis on Viedma ripening, and shows that to date many novel organic molecules can be obtained in enantiopure solid form. (strath.ac.uk)
- Hello everyone, I would be interested in trying to use TD to mimic fractional crystallization processes. (research-talk.org)
- The protein is normally unstable during the purification and crystallization processes. (nih.gov)
Crystals4
- Crystallization is the (natural or artificial) process of formation of solid crystals from a homogeneous solution or melt , or more rarely directly from a gas . (newworldencyclopedia.org)
- The results suggest that the shear field generated during printing enhances the formation of oriented crystals and that rapid undercooling, with a relatively high temperature gradient within the nozzle, appears to be the dominant influencing factor in crystallisation in this case. (diamond.ac.uk)
- Crystallization imagers are installed at 20 °C and 4 °C for imaging crystals in 96-well plates. (colorado.edu)
- The crystallization was carried out using the capillary counter-diffusion technique, which facilitates the screening, manipulation and transport of the crystals and allows the collection of X-ray data directly from the capillary in which the crystals were grown. (nih.gov)
Experiments4
- A team of Bristol Myers Squibb scientists is once again sending experiments into space, where microgravity conditions better support protein crystallization. (bms.com)
- Experiments suggest that, at the beginning of the crystallization process, molecules first form a disordered clump and then start rearranging into a crystal from within that group, as if the cards have to be mixed into a pile first before they can form a deck. (materialstoday.com)
- Allows setting up crystallisation drops with volumes as low as 50 nl protein + 50 nl reservoir and 1-3 protein samples per condition, thus 96-288 experiments can be done in one plate. (lu.se)
- Performs automatic imaging of crystallisation experiments at 20 °C using visible and UV light. (lu.se)
Methods4
- Covered methods are protein expression in E. coli , affinity chromatography, ion exchange chromatography, preparative and analytical gel filtration, crystallization, X-ray diffraction, and photometric assays. (jove.com)
- This manuscript describes methods for FAHD protein expression in E. coli , affinity chromatography, ion exchange chromatography, ammonium sulfate precipitation, preparative and analytical gel filtration, crystallization, X-ray diffraction, and photometric assays. (jove.com)
- Different methods were developed and employed to understand the influence of small organic solvents on the crystallization of paracetamol. (hu-berlin.de)
- Discussions focused on progress in high-throughput methods for cloning, production, purification, and crystallization of proteins for X-ray crystallography and NMR studies. (nih.gov)
Diffraction3
- Broad XRD scattering together without any diffraction peaks confirm amorphous structure of network of the glass, sharp diffraction peaks indexed to cordierite appear after glass crystallization. (eurekalert.org)
- Crystallisation and annealing behaviour of two caesium borosilicate glass samples with approximate boroleucite composition were characterised by means of differential scanning calorimetry measurements as well as X-ray powder diffraction investigations with subsequent profile fitting of the observed patterns according to the Rietveld and/or Pawley method. (degruyter.com)
- The SSRL Crystallization Plate avoids manual manipulation of samples during crystal screening and diffraction data collection. (mitegen.com)
International Symposium on Industrial Crystallization1
- The next International Symposium on Industrial Crystallization will be held in Glasgow (UK) on 5-8 September 2023. (efce.info)
Temperature4
- The crystallization temperature of YSZ increases from 344 to 404 °C as the layer thickness decreases from 15 to 4 nm. (cambridge.org)
- At the onset temperature of glass crystallisation T x , on = 770 °C, it existed only for about 75 min. (degruyter.com)
- We have 3 temperature contolled walk-in crystallization rooms at 4, 20 and 30 o C with shelf space for hundreds of crystallization trays. (colorado.edu)
- The degree of MRO increases as a function of temperature and maximizes at 140 °C when crystallization starts to occur, which suggests that crystallization prerequires the development of nanoscale MRO that serves as the site of nucleation. (aip.org)
Formulation1
- Crystallisation of drug reduces the bioavailability of the drug resulting in reduction of efficacy of formulation. (imcdgroup.com)
Screens1
- The SBU also has an array of 96 well crystallization screens to determine optimal conditions for crystallization with only 1mg of protein. (nih.gov)
Thermodynamics and Transport Properties1
- The Pharma Challenge: a cross-cutting perspective from the WPs CAPE, Crystallization and Thermodynamics and Transport Properties. (efce.info)
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Optimisation1
- Using nanoliter volumes this liquid handling system pipets your optimisation screen directly into the crystallisation plate (pipetting range: 200 nL - 4 mL). (lu.se)
Proteins2
- Purified proteins are used for crystallization and antibody production and employed for enzyme assays. (jove.com)
- It is used for in-situ crystallization of proteins on substrates affixed to magnetic sample pin bases. (mitegen.com)
Structural biology1
- The journal Acta Crystallographica Section F: Structural Biology and Crystallization Communications is now participating in PubMed Central, archives include volume 61, 2005. (nih.gov)
Experiment1
- The effect of buffer conditions and additives on protein stability can be probed, which is useful in preparation for a crystallisation experiment. (lu.se)
Fractional crystallization1
- Ether-based Aqueous Separations and Extractions (EASE) applies dimethyl ether-driven fractional crystallization (DME-FC) and zero liquid discharge (ZLD) technology to improve energy efficiency, reduce waste and reagent use. (ameslab.gov)
Purification and crystallization2
- In this paper, the expression, purification and crystallization of nsp10 in complex with nsp16 are reported. (iucr.org)
- The 2003 NIGMS Protein Purification and Crystallization Workshop was organized with the main goal of providing an effective platform for scientists to share and exchange ideas and data, to discuss progress and problems, and to address the most challenging bottlenecks. (nih.gov)
Nucleation2
- The crystallization process consists of two major events, nucleation and crystal growth which are driven by thermodynamic properties as well as chemical properties. (wikipedia.org)
- Supersaturation is the driving force of the crystallization process-the rates of nucleation and growth are driven by supersaturation within the solution. (newworldencyclopedia.org)
Crystalline phase1
- Crystallization is also a chemical solid-liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid crystalline phase occurs. (wikipedia.org)
Formation2
- Crystallisation inhibitors prevent the crystallisation of the drug by increasing viscosity or by formation of hydrogen bonds with the drug. (imcdgroup.com)
- This chapter provides a perspective on the current state-of-the-art research on the formation and crystallization mechanisms of ACC to vaterite. (tcd.ie)
Metastable intermediates1
- Non-equilibrium molecular dynamics simulations with periodic simulated annealing were used as a tool to probe the nature of precursors of the metastable intermediates occurring in the crystallization process. (hu-berlin.de)
Process13
- Crystallization is the process by which solid forms, where the atoms or molecules are highly organized into a structure known as a crystal. (wikipedia.org)
- Supersaturation is one of the driving forces of crystallization, as the solubility of a species is an equilibrium process quantified by Ksp. (wikipedia.org)
- There are many examples of natural process that involve crystallization. (wikipedia.org)
- Crystallization is a concept, developed in 1822 by the French writer Stendhal, which describes the process, or mental metamorphosis, in which unattractive characteristics of a new love are transformed into perceptual diamonds of shimmering beauty. (wikipedia.org)
- This journey or crystallization process, shown above, was detailed by Stendhal on the back of a playing card while speaking to Madame Gherardi, during his trip to the Salzburg salt mine. (wikipedia.org)
- Crystallization is a valuable process for both research and industrial applications. (newworldencyclopedia.org)
- The solution that remains after a crystallization process is called the mother liquor . (newworldencyclopedia.org)
- Chemists don't yet have enough control over the crystallization process to ensure the creation of the best crystal form, partly because chemists aren't sure how the earliest steps in crystallization occur. (materialstoday.com)
- The simple peptoid followed all the rules of a one-step crystallization process. (materialstoday.com)
- New types of crystal structures can be obtained by the presence of a surface during the crystallisation process. (icmab.es)
- The crystallization of drug carrying lipid nanoparticles (LNP) is a typical batch process for pharmaceutical products and is used here to demonstrate benefits, challenges and application possibilities of the conversion into a continuous microscale process. (asme.org)
- This contribution addresses the in-process cleaning of a micro heat exchanger for the continuous crystallization using ultrasound. (asme.org)
- The Bureau of Mines has conducted a laboratory and field corrosion testing program to determine materials of construction for the leaching and gas-sparging crystallization environment of the clay-HCl process in order to more fully utilize the alumina from domestically available kaolinitic clays. (cdc.gov)
Initial1
- Twenty years ago, the initial FEBS crystallization course took place in the Czech Republic, becoming a celebrated tradition for students and postdocs worldwide. (febs.org)
Antibody Fragments1
- They also added small antibody fragments to the protein solution to encourage crystallization. (nih.gov)
Pathways3
- The findings address an ongoing debate about crystallization pathways,' said materials scientist Jim De Yoreo at the US Department of Energy's Pacific Northwest National Laboratory (PNNL) and the University of Washington. (materialstoday.com)
- In pharmaceuticals, these various crystallization pathways can mean the difference between a drug that works versus one that doesn't. (materialstoday.com)
- Changes in any of these variables affect the lifetime of ACC and the crystallization rates and pathways to vaterite or other CaCO3 polymorphs. (tcd.ie)
Amorphous3
- Crystallization is therefore related to precipitation, although the result is not amorphous or disordered, but a crystal. (wikipedia.org)
- The evolution of medium range ordering (MRO) and crystallization behavior of amorphous TiO 2 films grown by atomic layer deposition (ALD) were studied using in situ four-dimensional scanning transmission electron microscopy. (aip.org)
- The films remain fully amorphous when grown at 120 °C or below, but they start showing crystallization of anatase phases when grown at 140 °C or above. (aip.org)
Workshop4
- The aim of the workshop is to foster interactions and to share information regarding protein production and crystallization between scientists involved in the NIH-funded Protein Structure Initiative, and between the PSI group and members of the international structural genomics community. (nih.gov)
- Protein Production and Crystallization Workshop, April 9-11, 2003. (nih.gov)
- In a second workshop the scope of the meeting was expanded to include crystallization. (nih.gov)
- The Protein Production and Crystallization Workshop was held at NIH, in Bethesda, in April 2003. (nih.gov)
Robot1
- For crystallization projects, the lab has access to a Mosquito crystallization robot, a MUVIS tryptophan fluorescence microscope and access to the APS synchrotron. (nih.gov)
Facility1
- The crystallisation facility is available after booking. (lu.se)
Behavior4
- Polishing the bonding surface, before or after crystallization, does not alter the fatigue behavior of bonded CAD-CAM lithium disilicate. (bvsalud.org)
- The aim of this study was to assess if the finishing/polishing of the bonding surface of lithium disilicate ceramic , prior to or after crystallization , would affect the fatigue behavior of a bonded restorations. (bvsalud.org)
- Neither the finishing/polishing procedure of the bonding surface, nor the moment (prior to or after crystallization ), affected the fatigue behavior of bonded milled lithium disilicate. (bvsalud.org)
- Finishing/polishing the bonding surface of milled lithium disilicate, before or after crystallization , does not alter the fatigue behavior of the bonded restorative set, although there is some influence on roughness and topography . (bvsalud.org)
Production2
- Artificial crystallization includes two major groups of applications: crystal production and purification. (newworldencyclopedia.org)
- 98%) may be employed for crystallization or antibody production. (jove.com)
Reagent1
- The crystallization pictured in this section shows purification of a roughly \(1 \: \text{g}\) sample of old \(\ce{N}\)-bromosuccinimide (NBS), which was found in its reagent bottle as an orange powder. (libretexts.org)
Examples1
- There are many examples of crystallization in nature, some of which are noted below. (newworldencyclopedia.org)
Dimensions1
- The Professional Preferences Crystallization Inventory (PPCI) is an important instrument which evaluates two dimensions: choosing a career and thus promoting professional development. (bvsalud.org)
Organic1
- If a crystallization is to be performed using flammable organic solvents, a steam bath is recommended and in some situations necessary (when using diethyl ether, acetone, or low-boiling petroleum ether). (libretexts.org)
Composition1
- The latter value is consistent with the reported crystallization enthalpy for YSZ powder of the same composition prepared by precipitation from aqueous solution. (cambridge.org)
Equilibrium1
- Once the solution is no longer supersaturated, the solid-liquid system reaches equilibrium and crystallization is complete, unless the operating conditions are modified from equilibrium so that the solution becomes supersaturated again. (newworldencyclopedia.org)
Melt1
- In this webinar, we explore characterizing the impact of shear induced crystallization on a polymer melt. (anton-paar.com)
Method4
- In a new paper published in Light Science & Application , a team of scientists, led by Professor Zhiguo Xia and Professor Qinyuna Zhang from South China University of Technology, has developed an efficient red-emitting Mg2Al4Si5O18:Eu2+ composite phosphor by using thermal-treatment induced glass structure relaxation and crystallization method, and Professor Lixin Ning from Anhui Normal University performed the theoretical calculation to support the experimental findings. (eurekalert.org)
- Noteworthy, there are rare reports of fabrication of Eu2+ activated red-emitting glass ceramic phosphor by glass crystallization method. (eurekalert.org)
- The time-resolved Raman spectroscopy crystallization data was processed using a newly developed objective function based non-negative matrix factorization method (NMF). (hu-berlin.de)
- Efficient Method for Protein Crystallization. (nih.gov)
Solution1
- For artificial crystallization of a solute from solution, the conditions must be adjusted such that the solution becomes supersaturated with the solute. (newworldencyclopedia.org)
Situ1
- In situ Raman spectroscopy was used with a custom-made acoustic levitator to follow crystallization. (hu-berlin.de)
Suitable1
- This model is also suitable for the crystallization of polymers under other flow fields. (aps.org)
Drug1
- April 9, 2008 - Rotigotine extended-release transdermal systems ( Neupro , Schwarz Pharma [UCB Group]) are being recalled because of drug crystallization that can hamper absorption, the US Food and Drug Administration (FDA) announced today. (medscape.com)
Honey2
- Honey crystallization (nearly all types of honey crystallize). (wikipedia.org)
- Crystallization of honey . (newworldencyclopedia.org)
Glass1
- The crystallization slightly suppresses the bioactivity and dissolution of the glass. (rsc.org)
Group1
- and POST group, which received the treatment after its crystallization . (bvsalud.org)
Data1
- An orthogonal time-lapse photography was used in conjunction with NMF to get unique and accurate factors that pertain to the spectra and concentrations of different moieties of paracetamol crystallization existing as latent components in the untreated data. (hu-berlin.de)
Chemical1
- In chemical engineering, crystallization occurs in a crystallizer. (wikipedia.org)
Research1
- The BCC is designed around facilitating access to crystallization and characterisation services for the clients that do not have access to either the equipment or expertise required for their scientific research campaign. (www.csiro.au)