Clostripain (, ''clostridiopeptidase B'', ''clostridium histolyticum proteinase B'', ''alpha-clostridipain'', ''clostridiopeptidase'', ''Endoproteinase Arg-C'') is a
proteinase
A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the ...
that cleaves
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...
s on the carboxyl peptide bond of
arginine
Arginine is the amino acid with the formula (H2N)(HN)CN(H)(CH2)3CH(NH2)CO2H. The molecule features a guanidino group appended to a standard amino acid framework. At physiological pH, the carboxylic acid is deprotonated (−CO2−) and both the a ...
. It was isolated from ''
Clostridium histolyticum
''Hathewaya histolytica'' (formerly ''Clostridium histolyticum'') is a species of bacteria found in feces and the soil. It is a motile, gram-positive, aerotolerant anaerobe. ''H. histolytica'' is pathogenic in many species, including guinea p ...
''. The isoelectric point of the
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...
is 4.8-4.9 (at 8 °C), and optimum pH is 7.4~7.8 (against α-benzoyl-arginine ethyl ester). The composition of the enzyme is indicated to be of two chains of relative
molecular mass
The molecular mass (''m'') is the mass of a given molecule: it is measured in daltons (Da or u). Different molecules of the same compound may have different molecular masses because they contain different isotopes of an element. The related quant ...
45,000 and 12,500.
See also
*
Benzoyl
In organic chemistry, benzoyl (, ) is the functional group with the formula C6H5CO-. It can be viewed as benzaldehyde missing one hydrogen.
The term "benzoyl" should not be confused with benzyl, which has the formula C6H5CH2. The benzoyl grou ...
*
Ethyl ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are ...
References
External links
*
*
EC 3.4.22
Post-translational modification
{{hydrolase-stub