Pronase (EC 3.4.24.4)

Pronase is the name given to a group of proteolytic enzymes that are produced in the culture supernatant of Streptomyces griseus K-1 (1 –3 ). Pronase is known to contain at least ten proteolytic components: five serine-type proteases, two Zn²⁺ endopeptidases, two Zn²⁺ -leucine aminopeptidases, and one Zn²⁺ carboxypeptidase (4 ,5 ). Pronase therefore has very broad specificity, and is used in cases where extensive or complete degradation of protein is required. It has been used, for example, to reveal the protein components of cell organelles by the hydrolysis of tissue slices (6 ), and as an alternative to proteinase K to remove protein during plasmid DNA (7 ), chromosomal DNA (8 ), and RNA isolation (9 –11 ). Another use of pronase is the production of a protein hydrolysate suitable for amino acid analysis (12 ,13 ).