FIELD: biotechnology.
SUBSTANCE: invention represents a polypeptide variant having isopropyl malate synthase activity, containing one or more substitutions selected from a group consisting of 1) replacing the amino acid residue corresponding to position 138 with another amino acid residue, 2) replacing the amino acid residue corresponding to position 162 with another amino acid residue, 3) replacing the amino acid residue corresponding to position 211 with another amino acid residue, 4) replacing the amino acid residue corresponding to position 245 with another amino acid residue and 5) replacing the amino acid residue corresponding to position 588 with another amino acid residue in the amino acid sequence SEQ ID NO: 1. Invention also relates to a method of producing L-leucine, comprising a stage of culturing in a medium of a microorganism of the genus Corynebacterium, which produces L-leucine, wherein the microorganism contains said version of the polypeptide, a polynucleotide encoding it or a vector comprising it.
EFFECT: invention enables to obtain L-isoleucine with high efficiency.
14 cl, 13 tbl, 4 ex
