Cellular Permeability and Extracellular Formation of Glutamic Acid in Brevibacterium flavum

Abstract

The accumulation of glutamate from glucose in the culture medium was strongly suppressed by 0.05% oleate or 30 [gamma]ml biotin; it was stimulated by penicillin-G, Tween-40 and -60 so that the glutamate formation parallelled the cell growth. The amino-acid-releasing rate of the cells grown in biotin-rich(30 [gamma]/ml) or oleic-acid-containing (300 mg/l) medium was far lower than that grown in biotin- or oleate-less medium; the effect of biotin or oleate was counteracted by penicillin-G or Tween-60. Aspartate-[alpha]-ketoglutarate transaminase activity was markedly reduced by adding biotin to the medium. It was reversed by the addition of penicillin G or Tween-60. The transaminase activity of the cetyltrlmethylammonium-bromide-treated cells was not greatly affected by the presence of biotin in the medium.