METABOLIC PATTERNS OF NUTRITIONALLY DIFFERENTIATED CELL TYPES OF BACILLUS SUBTILIS

Abstract

An investigation, at the enzyme level, of nutritionally differentiated cell types (c.f. Gary and Bard, Jour. Bact. 64: 501-512. 1952) reveals that cells grown in a tryptone-yeast extract-glucose medium (C-cells) possess both the hexose mono- and diphosphate pathways of glucose dissimilation, but lack cytochrome oxidase activity. S-cells, cultivated in an ammonium chloride-glucose-salts medium, also possess the enzymes for both dissimilatory pathways; however, these cells lack the homolactic glucose fermentative capacity of C-cells. S-cells contain a vigorous cytochrome oxidase. The fermentative enzymes, aldolase, triose and lactate dehydrogenases, are present in reduced quantities in S-cells. Addition of a number of biological hydrogen acceptors to resting S-cells results in a vigorous heterolactic glucose fermentation. It is postulated that stimulation of fermentation occurs in the presence of hydrogen acceptors due to enhancement of hydrogen transport from reduced diphosphopyridine nucleotide coenzyme of the dehydrogenases, permitting more rapid turnover of the triose intermediate.