Methods in Molecular Biology • 16 Enzymes of Molecular Biology

CHAPTER 14

Pronase (EC 3.4.24.4)

Patricia J. Sweeney and John M. Walker

1. Introduction
   Pronase is the name given to a group of proteolytic enzymes that are
   produced in the culture supematant of Streptomyces griseus K- 1 (1-3).
   Pronase is known to contain at least ten proteolytic components: five
   serine-type proteases, two Zn 2+ endopeptidases, two Zn2+-leucine ami-
   nopeptidases, and one Zn 2+ 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).
   Traditionally, protein hydrolysates for amino acid analysis are pro-
   duced by hydrolysis in 6N HC1. However, this method has the disad-
   vantage that tryptophan is totally destroyed, serine and threonine
   partially (5-10%) destroyed, and most importantly, asparagine and
   glutamine are hydrolyzed to the corresponding acids. Digestion of the
   protein/peptide with pronase overcomes these problems, and is par-
   ticularly useful when the concentration of asparagine and glutamine is
   required. The use of pronase for this application is detailed in Section


2. The use of pronase in the preparation of optically active amino acids
   has been described. The hydrolysis of amino amides by pronase results
   in high-rate significant enantioselectivity and a high degree of conver-

From: Methods in Molecular Biology, VoL 16: Enzymes of Molecular Biology

Edited by: M. M. Burrell Copyright ©1993 Humana Press Inc., Totowa, NJ

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