Effects of biotin on glutamate production and fatty acid composition in Bacillus cereus 14B22

Publisher Website
Google Scholar
Abstract
Bacillus cereus 14B22 exhibits a biochemical regulation by biotin. In glucose–salts or citrate–salts media, limiting amounts of biotin restrict cellular synthesis and induce synthesis of high yields of extracellular L-glutamic acid. With nonlimiting levels of biotin, abundant cellular synthesis occurs without the concomitant accumulation of glutamate. The biotin status of cells was not reflected in experiments with cell-free extracts. Citrate was converted to glutamate at comparable rates by extracts of biotin-sufficient and biotin-deficient cells. The biotin requirement for growth can be replaced with Tween 80 or with a mixture of Tween 40 and oleic acid. The yields of glutamate given by cultures of these "fatty acid-grown cells" were intermediate between those obtained with biotin-deficient and biotin-sufficient cells. Biotin deficiency also altered the fatty acid composition of the cell membrane. The proportion of straight-chain to branched-chain fatty acids is significantly smaller in low-biotin cells than in high-biotin cells. These changes did not affect cellular permeability to glutamate. Variations in the morphology of B. cereus 14B22 as influenced by biotin and the fatty acid composition of the medium are described.

This publication has 0 references indexed in Scilit: