| 摘要 |
FIELD: biotechnology, antibiotics. SUBSTANCE: invention relates to preparing semi-synthetic beta-lactam antibiotics aminopenicillins and aminocephalosporins and their N-substituted derivatives also. Method involves enzymatic transformation of the parent beta-lactam compound in the presence of enzyme system. For realizing method biosynthetic beta-lactam compounds and their chemical analogues are used as parent beta-lactam compounds and biocatalysts of the 2-d generation based on immobilized cells comprising hydrolase for biosynthetic beta-lactams in combination with enzyme amino-beta-lactam synthase specific to derivatives of aminophenylacetic acid are used as enzymes. Amino acid esters are used as acylating agent that are added to reaction mass and flowing molar excess of acylating agent with respect to amino acid is maintained to be 3-4-fold and its total content is 1.9-2.1 M/M of the parent beta-lactam, not above. End products are isolated by direct precipitation as amino-beta- lactams by pH value change, medium dielectric permeability value or by addition of specific precipitating agent, preferably alpha- naphthol, or as N-substituted derivative by pH value change. Invention provides elevating effectiveness of method with its simultaneous simplification. EFFECT: enhanced yield, improved quality of product. 4 cl, 9 ex |
