BIOSYNTHESIS OF L-LYSINE AND L-THREONINE IN BREVIBACTERIUM .7. EFFECT OF BIOTIN LEVELS ON L-LYSINE FORMATION IN BREVIBACTERIUM-LACTOFERMENTUM

The relationship between L-lysine production and biotin levels in culture medium was investigated in Brevibacterium lactofermentum. Strain AJ3799 accumulated 34 mg/ml and 42 mg/ml of L-Iysine· HCI in the presence of 50 Kg/Iiter and 500 Kg/liter, respectively, of biotin in culture medium. This increase in L-Iysine production was observed with various kinds of lysine producers and also with resting cells grown in biotin poor medium. Biotin functioned as an effector only when glucose or pyruvate was used as a substrate. And this effect was accompanied with reduction of carbon dioxide liberation, as well as decreased accumulation of L-alanine, L-valine and L-Ieucine. On the other hand, penicillin and some surfactants had no effect on the function of biotin. These data suggest a significant new role for biotin in Brev. lactofermentum. © 1979 Taylor & Francis Group, LLC.