Peptide Syntheses with Proteinases. Fragment Condensation of ZLeuGlnGlyOH or ZGlnGlyOH with HLeuValNH2 Using Metalloproteinases

Abstract

Abstract The crude preparations of microbial metalloproteinase from Bacillus subtilis var. amyloliquefaciens (Prolisin) catalyzed the condensation of ZLeuGlnGlyOH or ZGlnGlyOH with HLeuValNH2 in the presence of the serineproteinase inhibitor from potatoes to give the corresponding Z-penta or tetra-peptide amide in good yields in an aqueous buffer solution. Two other metalloproteinases, from Bacillus thermoproteoliticus (Thermolysin or Thermoase) and Streptomyces caespitosus (Tacynase N), also catalyzed this reaction; however, they gave poorer results than Prolisin. The yields of the coupling products were affected most by the concentration of the substrates, among the several factors investigated. Addition of a small amount of an organic solvent sometimes promoted the yield for this method.