External links
- Saccharopepsin at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
| Vertebrate | |
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| Pathogenic | |
| Plant | |
| Cathepsin | |
| Activity | |
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| Regulation | |
| Classification | |
| Kinetics | |
| Types |
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| Saccharopepsin | |||||||||
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| Identifiers | |||||||||
| EC no. | 3.4.23.25 | ||||||||
| CAS no. | 37228-80-1 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
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Saccharopepsin (EC 3.4.23.25, yeast endopeptidase A, Saccharomyces aspartic proteinase, aspartic proteinase yscA, proteinase A, proteinase yscA, yeast proteinase A, Saccharomyces cerevisiae aspartic proteinase A, PRA) is an enzyme. [1] [2] [3] This enzyme catalyses the following chemical reaction
This enzyme is present in baker's yeast ( Saccharomyces cerevisiae ).
Proteinase A is an aspartic proteinase found in Saccharomyces cerevisiae, commonly called “Brewer’s Yeast” or “Baker’s Yeast” and is used in the fermentation processes of beer and wine making. Fermentation can cause stress conditions for Saccharomyces cerevisiae and proteinase A can be excreted from the cell. [4]
Structure
Proteinase A is relatively simple protein and is 329 amino acid residues in length. It is composed of both alpha helices and beta pleated sheets, with beta pleated sheets being the prevailing structure. [5]
Proteinase A has two symmetrical lobes. The lobes are folded so that an aspartic acid from each lobe line up to form the active site of the protein. The structure of proteinase A is stabilized by two separate disulfide bridges, one in each lobe. The structure also includes a malleable sheet composed of beta pleated sheets that can cover and uncover the active site. [4]
Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitute 1% of all described fungal species.
Galactokinase is an enzyme (phosphotransferase) that facilitates the phosphorylation of α-D-galactose to galactose 1-phosphate at the expense of one molecule of ATP. Galactokinase catalyzes the second step of the Leloir pathway, a metabolic pathway found in most organisms for the catabolism of α-D-galactose to glucose 1-phosphate. First isolated from mammalian liver, galactokinase has been studied extensively in yeast, archaea, plants, and humans.
In biology and biochemistry, protease inhibitors, or antiproteases, are molecules that inhibit the function of proteases. Many naturally occurring protease inhibitors are proteins.
Enoyl-CoA-(∆) isomerase (EC 5.3.3.8, also known as dodecenoyl-CoA- isomerase, 3,2-trans-enoyl-CoA isomerase, ∆3 ,∆2 -enoyl-CoA isomerase, or acetylene-allene isomerase, is an enzyme that catalyzes the conversion of cis- or trans-double bonds of coenzyme A bound fatty acids at gamma-carbon to trans double bonds at beta-carbon as below:
Protein splicing is an intramolecular reaction of a particular protein in which an internal protein segment is removed from a precursor protein with a ligation of C-terminal and N-terminal external proteins on both sides. The splicing junction of the precursor protein is mainly a cysteine or a serine, which are amino acids containing a nucleophilic side chain. The protein splicing reactions which are known now do not require exogenous cofactors or energy sources such as adenosine triphosphate (ATP) or guanosine triphosphate (GTP). Normally, splicing is associated only with pre-mRNA splicing. This precursor protein contains three segments—an N-extein followed by the intein followed by a C-extein. After splicing has taken place, the resulting protein contains the N-extein linked to the C-extein; this splicing product is also termed an extein.
The enzyme Trehalase is a glycoside hydrolase, produced by cells in the brush border of the small intestine, which catalyzes the conversion of trehalose to glucose. It is found in most animals.
In molecular biology, the protein domain Saccharopine dehydrogenase (SDH), also named Saccharopine reductase, is an enzyme involved in the metabolism of the amino acid lysine, via an intermediate substance called saccharopine. The Saccharopine dehydrogenase enzyme can be classified under EC 1.5.1.7, EC 1.5.1.8, EC 1.5.1.9, and EC 1.5.1.10. It has an important function in lysine metabolism and catalyses a reaction in the alpha-Aminoadipic acid pathway. This pathway is unique to fungal organisms therefore, this molecule could be useful in the search for new antibiotics. This protein family also includes saccharopine dehydrogenase and homospermidine synthase. It is found in prokaryotes, eukaryotes and archaea.
Cystathionine beta-lyase, also commonly referred to as CBL or β-cystathionase, is an enzyme that primarily catalyzes the following α,β-elimination reaction
Kexin is a prohormone-processing protease, specifically a yeast serine peptidase, found in the budding yeast. It catalyzes the cleavage of -Lys-Arg- and -Arg-Arg- bonds to process yeast alpha-factor pheromone and killer toxin precursors. The human homolog is PCSK4. It is a family of subtilisin-like peptidases. Even though there are a few prokaryote kexin-like peptidases, all kexins are eukaryotes. The enzyme is encoded by the yeast gene KEX2, and usually referred to in the scientific community as Kex2p. It shares structural similarities with the bacterial protease subtilisin. The first mammalian homologue of this protein to be identified was furin. In the mammal, kexin-like peptidases function in creating and regulating many differing proproteins.
Exopolyphosphatase (PPX) is a phosphatase enzyme which catalyzes the hydrolysis of inorganic polyphosphate, a linear molecule composed of up to 1000 or more monomers linked by phospho-anhydride bonds. PPX is a processive exophosphatase, which means that it begins at the ends of the polyphosphate chain and cleaves the phospho-anhydride bonds to release orthophosphate as it moves along the polyphosphate molecule. PPX has several characteristics which distinguish it from other known polyphosphatases, namely that it does not act on ATP, has a strong preference for long chain polyphosphate, and has a very low affinity for polyphosphate molecules with less than 15 phosphate monomers.
Glucanases are enzymes that break down large polysaccharides via hydrolysis. The product of the hydrolysis reaction is called a glucan, a linear polysaccharide made of up to 1200 glucose monomers, held together with glycosidic bonds. Glucans are abundant in the endosperm cell walls of cereals such as barley, rye, sorghum, rice, and wheat. Glucanases are also referred to as lichenases, hydrolases, glycosidases, glycosyl hydrolases, and/or laminarinases. Many types of glucanases share similar amino acid sequences but vastly different substrates. Of the known endo-glucanases, 1,3-1,4-β-glucanase is considered the most active.
Very-long-chain enoyl-CoA reductase (EC 1.3.1.93, TSC13 (gene name), CER10 (gene)) is an enzyme with systematic name very-long-chain acyl-CoA:NADP+ oxidoreductase. This enzyme catalyses the following chemical reaction
Cerevisin is an enzyme. This enzyme catalyses the following chemical reaction
Penicillopepsin is an enzyme. This enzyme catalyses the following chemical reaction
Endothiapepsin is an enzyme. This enzyme catalyses the following chemical reaction
Candidapepsin is an enzyme. This enzyme catalyses the following chemical reaction
Yapsin 1 is an enzyme. This enzyme catalyses the following chemical reaction
Saccharolysin is an enzyme. This enzyme catalyses the following chemical reaction
The yeast mitochondrial code is a genetic code used by the mitochondrial genome of yeasts, notably Saccharomyces cerevisiae, Candida glabrata, Hansenula saturnus, and Kluyveromyces thermotolerans.
Aerobic fermentation or aerobic glycolysis is a metabolic process by which cells metabolize sugars via fermentation in the presence of oxygen and occurs through the repression of normal respiratory metabolism. It is referred to as the Crabtree effect in yeast. and is part of the Warburg effect in tumor cells. While aerobic fermentation does not produce adenosine triphosphate (ATP) in high yield, it allows proliferating cells to convert nutrients such as glucose and glutamine more efficiently into biomass by avoiding unnecessary catabolic oxidation of such nutrients into carbon dioxide, preserving carbon-carbon bonds and promoting anabolism.
