[Native and modified subtilisin 72 as a catalyst of peptide synthesis in media with low water content].
The catalytic efficiencies of native subtilisin, its noncovalent complex with polyacrylic acid, and the subtilisin covalently immobilized in a cryogel of polyvinyl alcohol were studied in the reaction of peptide coupling in mixtures of organic solvents with a low water content in dependence on the medium composition, reaction time, and biocatalyst concentration. It was established that, in media with a DMF content > 80%, the synthase activity of modified subtilisins is higher than that of the native subtilisin. The use of N-acylpeptides with a free carboxyl group was found to be possible in organic solvents during the enzymatic synthesis catalyzed by both native and immobilized subtilisin. A series of tetrapeptide p-nitroanilides of the general formula Z-Ala-Ala-Xaa-Yaa-pNA (where Xaa is Leu, or Glu and Yaa is Phe or Asp) was obtained in the presence of immobilized enzyme in yields of 70-98% in DMF-MeCN without any activation of the carboxyl component and without protection of side ionogenic groups of polyfunctional amino acids.
Faculty of Chemistry, Moscow State University, Vorob'evy gory, Moscow, 119992 Russia.
A V
AV
Bacheva
O V
OV
Baĭbak
A V
AV
Beliaeva
E N
EN
Lysogoskaia
E S
ES
Oksenoĭt
V I
VI
Lozinskiĭ
I Iu
IIu
Filippova
D002384:Catalysis; D010455:Peptides / Q000138:chemical synthesis*; D013381:Subtilisins / Q000378:metabolism*; D014867:Water / Q000737:chemistry*
D010455:Peptides; D014867:Water; D013381:Subtilisins