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N-Glycosyl Hydrolases: A class of enzymes involved in the hydrolysis of the N-glycosidic bond of nitrogen-linked sugars.Hydrolases: Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.Glycoside HydrolasesEpoxide Hydrolases: Enzymes that catalyze reversibly the formation of an epoxide or arene oxide from a glycol or aromatic diol, respectively.Carboxylic Ester Hydrolases: Enzymes which catalyze the hydrolysis of carboxylic acid esters with the formation of an alcohol and a carboxylic acid anion.Lysosomes: A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured. Such rupture is supposed to be under metabolic (hormonal) control. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Acid Phosphatase: An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.2.GlucuronidaseHexosaminidases: Enzymes that catalyze the hydrolysis of N-acylhexosamine residues in N-acylhexosamides. Hexosaminidases also act on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES.Mannosephosphates: Phosphoric acid esters of mannose.N-Acetylmuramoyl-L-alanine Amidase: An autolytic enzyme bound to the surface of bacterial cell walls. It catalyzes the hydrolysis of the link between N-acetylmuramoyl residues and L-amino acid residues in certain cell wall glycopeptides, particularly peptidoglycan. EC 3.5.1.28.Peptide Hydrolases: Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.Mucolipidoses: A group of inherited metabolic diseases characterized by the accumulation of excessive amounts of acid mucopolysaccharides, sphingolipids, and/or glycolipids in visceral and mesenchymal cells. Abnormal amounts of sphingolipids or glycolipids are present in neural tissue. INTELLECTUAL DISABILITY and skeletal changes, most notably dysostosis multiplex, occur frequently. (From Joynt, Clinical Neurology, 1992, Ch56, pp36-7)Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Thiolester HydrolasesReceptor, IGF Type 2: A receptor that is specific for IGF-II and mannose-6-phosphate. The receptor is a 250-kDa single chain polypeptide which is unrelated in structure to the type 1 IGF receptor (RECEPTOR, IGF TYPE 1) and does not have a tyrosine kinase domain.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Acetylglucosaminidase: A beta-N-Acetylhexosaminidase that catalyzes the hydrolysis of terminal, non-reducing 2-acetamido-2-deoxy-beta-glucose residues in chitobiose and higher analogs as well as in glycoproteins. Has been used widely in structural studies on bacterial cell walls and in the study of diseases such as MUCOLIPIDOSIS and various inflammatory disorders of muscle and connective tissue.alpha-L-Fucosidase: An enzyme that catalyzes the hydrolysis of an alpha L-fucoside to yield an alcohol and L-fucose. Deficiency of this enzyme can cause FUCOSIDOSIS. EC 3.2.1.51.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Xylosidases: A group of enzymes that catalyze the hydrolysis of alpha- or beta-xylosidic linkages. EC 3.2.1.8 catalyzes the endo-hydrolysis of 1,4-beta-D-xylosidic linkages; EC 3.2.1.32 catalyzes the endo-hydrolysis of 1,3-beta-D-xylosidic linkages; EC 3.2.1.37 catalyzes the exo-hydrolysis of 1,4-beta-D-linkages from the non-reducing termini of xylans; and EC 3.2.1.72 catalyzes the exo-hydrolysis of 1,3-beta-D-linkages from the non-reducing termini of xylans. Other xylosidases have been identified that catalyze the hydrolysis of alpha-xylosidic bonds.Cellulase: An endocellulase with specificity for the hydrolysis of 1,4-beta-glucosidic linkages in CELLULOSE, lichenin, and cereal beta-glucans.Cellvibrio: A genus of aerobic, gram-negative, motile, slightly curved, rod-shaped bacteria. (From Bergey's Manual of Determinative Bacteriology, 9th ed)beta-Glucosidase: An exocellulase with specificity for a variety of beta-D-glycoside substrates. It catalyzes the hydrolysis of terminal non-reducing residues in beta-D-glucosides with release of GLUCOSE.Galactosidases: A family of galactoside hydrolases that hydrolyze compounds with an O-galactosyl linkage. EC 3.2.1.-.beta-Mannosidase: An enzyme that catalyzes the hydrolysis of terminal, non-reducing beta-D-mannose residues in beta-D-mannosides. The enzyme plays a role in the lysosomal degradation of the N-glycosylprotein glycans. Defects in the lysosomal form of the enzyme in humans result in a buildup of mannoside intermediate metabolites and the disease BETA-MANNOSIDOSIS.Endo-1,4-beta Xylanases: Enzymes which catalyze the endohydrolysis of 1,4-beta-D-xylosidic linkages in XYLANS.Xylans: Polysaccharides consisting of xylose units.Acid Anhydride Hydrolases: A group of enzymes that catalyze the hydrolysis of diphosphate bonds in compounds such as nucleoside di- and tri-phosphates, and sulfonyl-containing anhydrides such as adenylylsulfate. (Enzyme Nomenclature, 1992) EC 3.6.Arylsulfatases: Enzymes that catalyze the hydrolysis of a phenol sulfate to yield a phenol and sulfate. Arylsulfatase A, B, and C have been separated. A deficiency of arylsulfatases is one of the causes of metachromatic leukodystrophy (LEUKODYSTROPHY, METACHROMATIC). EC 3.1.6.1.beta-N-Acetylhexosaminidases: A hexosaminidase specific for non-reducing N-acetyl-D-hexosamine residues in N-acetyl-beta-D-hexosaminides. It acts on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES. Two specific mammalian isoenzymes of beta-N-acetylhexoaminidase are referred to as HEXOSAMINIDASE A and HEXOSAMINIDASE B. Deficiency of the type A isoenzyme causes TAY-SACHS DISEASE, while deficiency of both A and B isozymes causes SANDHOFF DISEASE. The enzyme has also been used as a tumor marker to distinguish between malignant and benign disease.DisaccharidasesSequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Pyrophosphatases: A group of enzymes within the class EC 3.6.1.- that catalyze the hydrolysis of diphosphate bonds, chiefly in nucleoside di- and triphosphates. They may liberate either a mono- or diphosphate. EC 3.6.1.-.Cathepsins: A group of lysosomal proteinases or endopeptidases found in aqueous extracts of a variety of animal tissues. They function optimally within an acidic pH range. The cathepsins occur as a variety of enzyme subtypes including SERINE PROTEASES; ASPARTIC PROTEINASES; and CYSTEINE PROTEASES.AmidohydrolasesGlucosidases: Enzymes that hydrolyze O-glucosyl-compounds. (Enzyme Nomenclature, 1992) EC 3.2.1.-.Mannosidases: Glycoside hydrolases that catalyze the hydrolysis of alpha or beta linked MANNOSE.Cathepsin D: An intracellular proteinase found in a variety of tissue. It has specificity similar to but narrower than that of pepsin A. The enzyme is involved in catabolism of cartilage and connective tissue. EC 3.4.23.5. (Formerly EC 3.4.4.23).Cell Wall: The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.Monocrotophos: An organophosphate insecticide that inhibits monoamine oxidase and acetylcholinesterase. It has been shown to be genotoxic.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Transferases (Other Substituted Phosphate Groups): A class of enzymes that transfers substituted phosphate groups. EC 2.7.8.Cellulases: A family of glycosidases that hydrolyse crystalline CELLULOSE into soluble sugar molecules. Within this family there are a variety of enzyme subtypes with differing substrate specificities that must work together to bring about complete cellulose hydrolysis. They are found in structures called CELLULOSOMES.Catalytic Domain: The region of an enzyme that interacts with its substrate to cause the enzymatic reaction.EsterasesKinetics: The rate dynamics in chemical or physical systems.Vacuoles: Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.Cellulose: A polysaccharide with glucose units linked as in CELLOBIOSE. It is the chief constituent of plant fibers, cotton being the purest natural form of the substance. As a raw material, it forms the basis for many derivatives used in chromatography, ion exchange materials, explosives manufacturing, and pharmaceutical preparations.