|
Pseudomonalisin
The sedolisin (MEROPS S53) family of peptidases are a family of serine proteases structurally related to the subtilisin (S8) family. Well-known members of this family include sedolisin ("pseudomonalisin") found in ''Pseudomonas'' bacteria, xanthomonalisin ("sedolisin-B"), physarolisin as well as animal tripeptidyl peptidase I. It is also known as sedolysin or serine-carboxyl peptidase. This group of enzymes contains a variation on the catalytic triad: unlike S8 which uses Ser-His-Asp, this group runs on Ser-Glu-Asp, with an additional acidic residue Asp in the oxyanion hole. Their optimal pH is around 3. Most members of the family are produced as a precursor protein with N-terminal () and sometimes C-terminal peptides that need to be cleaved off. Family members Sedolisin Sedolisin (, ''pseudomonapepsin'', ''sedolysin'') is a serine protease. It is secreted by ''Pseudomonas'' sp. 101. It performs hydrolysis of the B chain of insulin at -Glu13-Ala-, -Leu15-Tyr- and -Phe25-Ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MEROPS
MEROPS is an online database for peptidases (also known as proteases, proteinases and proteolytic enzymes) and their inhibitors. The classification scheme for peptidases was published by Rawlings & Barrett in 1993, and that for protein inhibitors by Rawlings ''et al.'' in 2004.Rawlings, N.D., Tolle, D.P. & Barrett, A.J. (2004) "Evolutionary families of peptidase inhibitors." ''Biochem J'' 378, 705-716. The most recent version, MEROPS 12.5, was released in September 2023. Overview The classification is based on similarities at the tertiary and primary structural levels. Comparisons are restricted to that part of the sequence directly involved in the reaction, which in the case of a peptidase must include the active site, and for a protein inhibitor the reactive site. The classification is hierarchical: sequences are assembled into families, and families are assembled into clans. Each peptidase, family, and clan has a unique identifier. Classification Family The families of pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peptidases
A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the formation of new protein products. They do this by cleaving the peptide bonds within proteins by hydrolysis, a reaction where water breaks bonds. Proteases are involved in numerous biological pathways, including digestion of ingested proteins, protein catabolism (breakdown of old proteins), and cell signaling. In the absence of functional accelerants, proteolysis would be very slow, taking hundreds of years. Proteases can be found in all forms of life and viruses. They have independently evolved multiple times, and different classes of protease can perform the same reaction by completely different catalytic mechanisms. Classification Based on catalytic residue Proteases can be classified into seven broad groups: * Serine proteases - using a serine alcohol * Cysteine proteases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine Protease
Serine proteases (or serine endopeptidases) are enzymes that cleave peptide bonds in proteins. Serine serves as the nucleophilic amino acid at the (enzyme's) active site. They are found ubiquitously in both eukaryotes and prokaryotes. Serine proteases fall into two broad categories based on their structure: chymotrypsin-like (trypsin-like) or subtilisin-like. Classification The MEROPS protease classification system counts 16 protein superfamily, superfamilies (as of 2013) each containing many protein family, families. Each superfamily uses the catalytic triad or dyad in a different protein fold and so represent convergent evolution of the catalytic mechanism. The majority belong to the S1 family of the PA clan (superfamily) of proteases. For protein superfamily, superfamilies, P: superfamily, containing a mixture of nucleophile class families, S: purely serine proteases. superfamily. Within each superfamily, protein family, families are designated by their catalytic nucl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtilisin
Subtilisin is a protease (a protein-digesting enzyme) initially obtained from ''Bacillus subtilis''. Subtilisins belong to subtilases, a group of serine proteases that – like all serine proteases – initiate the nucleophilic attack on the peptide (amide) bond through a serine residue at the active site. Subtilisins typically have molecular weights 27kDa. They can be obtained from certain types of soil bacteria, for example, '' Bacillus amyloliquefaciens'' from which they are secreted in large amounts. Nomenclature "Subtilisin" does not refer to a single protein, but to an entire clade under subtilases containing the classical subtilisins. The clade can be further divided into four groups: "true subtilisins" (containing the classical members), "high-alkaline subtilisins", "intracellular subtilisins", and "phylogenetically intermediate subtilisins" (PIS). Notable subtilisins include: Other non-commercial names include ''ALK-enzyme'', ''bacillopeptidase'', ''Bacillus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudomonas
''Pseudomonas'' is a genus of Gram-negative bacteria belonging to the family Pseudomonadaceae in the class Gammaproteobacteria. The 348 members of the genus demonstrate a great deal of metabolic diversity and consequently are able to colonize a wide range of niches and hosts. Their ease of culture ''in vitro'' and availability of an increasing number of ''Pseudomonas'' strain genome sequences has made the genus an excellent focus for scientific research; the best studied species include '' P. aeruginosa'' in its role as an opportunistic human pathogen, the plant pathogen '' P. syringae'', the soil bacterium '' P. putida'', and the plant growth-promoting '' P. fluorescens, P. lini, P. migulae'', and '' P. graminis''. Because of their widespread occurrence in water and plant seeds such as dicots, the pseudomonads were observed early in the history of microbiology. The generic name ''Pseudomonas'' created for these organisms was defined in rather vague terms by Walter Migula i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tripeptidyl Peptidase I
Tripeptidyl-peptidase 1, also known as Lysosomal pepstatin-insensitive protease, is an enzyme that in humans is encoded by the ''TPP1'' gene, also known as ''CLN2''. TPP1 should not be confused with the TPP1 shelterin protein which protects telomeres and is encoded by the ACD gene. Mutations in the ''TPP1'' gene leads to late-infantile neuronal ceroid lipofuscinosis. Structure Gene The human gene ''TPP1'' encodes a member of the sedolisin family of serine protease enzymes. The human gene has 13 exons and locates at the chromosome band 11p15. It is also known as ''CLN2'', due to the relation to the disease. Protein The human TPP1 is 61kDa in size and composed of 563 amino acids. An isoform of 34.5kDa and 320 amino acids is generated by alternative splicing and a peptide fragment of 1-243 amino acid is missing. TPP1 contains a globular structure with a subtilisin-like fold, a Ser475- Glu272- Asp360 catalytic triad. It also contains an octahedrally coordinated Ca2+-binding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalytic Triad
A catalytic triad is a set of three coordinated amino acid residues that can be found in the active site of some enzymes. Catalytic triads are most commonly found in hydrolase and transferase enzymes (e.g. proteases, amidases, esterases, aminoacylase, acylases, lipases and β-lactamases). An acid-base (chemistry), base-nucleophile triad is a common motif for generating a nucleophilic residue for covalent catalysis. The residues form a charge-relay network to polarise and activate the nucleophile, which attacks the Substrate (chemistry), substrate, forming a covalent intermediate which is then hydrolysed to release the Product (chemistry), product and regenerate free enzyme. The nucleophile is most commonly a serine or cysteine, but occasionally threonine or even selenocysteine. The Protein tertiary structure, 3D structure of the enzyme brings together the triad residues in a precise orientation, even though they may be far apart in the sequence (Protein primary structure, primary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxyanion Hole
An oxyanion hole is a pocket in the active site of an enzyme that stabilizes transition state negative charge on a deprotonation, deprotonated oxygen or alkoxide. The pocket typically consists of backbone amides or positively charged residues. Stabilising the transition state lowers the activation energy necessary for the reaction, and so promotes enzyme catalysis, catalysis. For example, proteases such as chymotrypsin contain an oxyanion hole to stabilise the tetrahedral molecular geometry, tetrahedral intermediate anion formed during proteolytic, proteolysis and protects Substrate (chemistry), substrate's negatively charged oxygen from water molecules. Additionally, it may allow for insertion or positioning of a substrate, which would suffer from steric hindrance if it could not occupy the hole (such as 2,3-Bisphosphoglycerate, BPG in hemoglobin). Enzymes that catalyse multi-step reactions can have multiple oxyanion holes that stabilise different transition states in the reaction. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of Biomolecule, biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insulin
Insulin (, from Latin ''insula'', 'island') is a peptide hormone produced by beta cells of the pancreatic islets encoded in humans by the insulin (''INS)'' gene. It is the main Anabolism, anabolic hormone of the body. It regulates the metabolism of carbohydrates, fats, and protein by promoting the absorption of glucose from the blood into cells of the liver, fat cell, fat, and skeletal muscles. In these tissues the absorbed glucose is converted into either glycogen, via glycogenesis, or Fatty acid metabolism#Glycolytic end products are used in the conversion of carbohydrates into fatty acids, fats (triglycerides), via lipogenesis; in the liver, glucose is converted into both. Glucose production and secretion by the liver are strongly inhibited by high concentrations of insulin in the blood. Circulating insulin also affects the synthesis of proteins in a wide variety of tissues. It is thus an anabolic hormone, promoting the conversion of small molecules in the blood into large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiotensin I
Angiotensin is a peptide hormone that causes vasoconstriction and an increase in blood pressure. It is part of the renin–angiotensin system, which regulates blood pressure. Angiotensin also stimulates the release of aldosterone from the adrenal cortex to promote sodium retention by the kidneys. An oligopeptide, angiotensin is a hormone and a dipsogen. It is derived from the precursor molecule angiotensinogen, a serum globulin produced in the liver. Angiotensin was isolated in the late 1930s (first named "angiotonin" or "hypertensin", later renamed "angiotensin" as a consensus by the 2 groups that independently discovered it) and subsequently characterized and synthesized by groups at the Cleveland Clinic and Ciba laboratories. Precursor and types Angiotensinogen Angiotensinogen is an α-2-globulin synthesized in the liver and is a precursor for angiotensin, but has also been indicated as having many other roles not related to angiotensin peptides. It is a member of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthomonas
''Xanthomonas'' (from greek: ''xanthos'' – "yellow"; ''monas'' – "entity") is a genus of bacteria, many of which cause plant pathology, plant diseases. There are at least 27 plant associated ''Xanthomonas spp.'', that all together infect at least 400 plant species. Different species typically have specific host and/or tissue range and colonization strategies. Taxonomy The genus ''Xanthomonas'' has been subject of numerous taxonomic and phylogenetic studies and was first described as ''Bacterium vesicatorium'' as a pathogen of pepper and tomato in 1921. Dowson later reclassified the bacterium as ''Xanthomonas campestris'' and proposed the genus ''Xanthomonas''.''Xanthomonas'' was first described as a monotypic genus and further research resulted in the division into two groups, A and B. Later work using DNA:DNA hybridization has served as a framework for the general ''Xanthomonas'' species classification. Other tools, including multilocus sequence analysis and amplified fragmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
