Effects of carbon source sugars on the yield of amino acid production and sucrose metabolism in Brevibacterium flavum.

Abstract

l-Phenylalanine produced by Brevibacterium flavum mutant M-128 from fructose as the carbon source, was 1/3 to 1/4 of that from glucose. The production from sucrose gave a similar yield as that from glucose, but that from an equimolar mixture of glucose and fructose was half of that from glucose, l -Glutamic acid production was not so strongly affected by these carbon source sugars. When mutant M-128 was producing l-phenylalanine at the maximum rate, the intracellular level of F6P was much lower with fructose as the carbon source than with glucose. The level with sucrose was similar as that with glucose, but that with the mixture of glucose and fructose was 1/2 to 1/3 of that with glucose, rather similar to that with half the amount of glucose. The intracellular AMP concentration was found to inhibit FBPase almost completely in the cells grown on any of these carbon source sugars. Toluenized cells of B. flavum strains able to grow on sucrose showed PEP-dependent PTS activity with sucrose as the sugar subst...