Method of preparation of a compound using a genetically modified homolactic thermophilic bacilli

Abstract

Disclosed herein is a genetic modification of moderately thermophilicspecies that are facultative anaerobic and homolactic. The method includes introducing DNA cloned in a thermosensitive plasmid system containing a pSH71 replicon or a homologue thereof into cells of a moderately thermophilicspecies that is facultative anaerobic and homolactic; culturing the cells on a selective medium at a permissive temperature to select transformed cells; culturing the transformed cells on a selective medium at a non-permissive temperature to select transformed cells capable of growing on the selective medium at the non-permissive temperature. The method can modify the Bacilli for R-lactic acid production, production of other organic acids than lactic acid, alcohol, enzymes, amino acids, and vitamins. Thespecies may be modified by replacing the S-lactate dehydrogenase gene by a DNA construct including a DNA sequence encoding R-lactate dehydrogenase.