Showing papers on "2,3-Butanediol published in 1988"
TL;DR: The cells appeared to regulate themselves such that energy generation is optimal subject to the constraint that the cells do not produce more reducing equivalents than can be oxidized by the electron transport system.
Abstract: Bacillus polymyxa produces (R, R)-2,3-butanediol from a variety of carbohydrates. Other metabolites are also produced including acetoin, acetate, lactate, and ethanol. The excretion of each metabolite was found to depend on the relative availability of oxygen to the culture. When the relative oxygen uptake rate was high, enhanced yields of acetate and acetoin were noted. At an intermediate oxygen availability, the butanediol yield was maximal. When the availability of oxygen was more restricted, higher yields of lactate and ethanol occurred. The cells appeared to regulate themselves such that energy generation is optimal subject to the constraint that the cells do not produce more reducing equivalents than can be oxidized by the electron transport system. The dependence of each product yield on the relative oxygen availability was determined, and this knowledge was used to carry out a fed-batch fermentation that attained a final butanediol concentration of over 40 g/L in 50 h.
106 citations
13 citations
TL;DR: The biochemistry and physiology of 2,3‐butanediol metabolism has been studied in a number of selected yeast species and an attempt is made to explain these phenomena on the basis of the substrate specificity of the two enzymes which oxidize 2, 3‐butanol in C. utilis.
Abstract: The biochemistry and physiology of 2,3-butanediol metabolism has been studied in a number of selected yeast species. Candida utilis CBS 621 exhibited diauxic growth on 2,3-butanediol. The first phase was characterized bu the utilization of the two optically active stereoisomers and associated accumulatoin. In the second phase of growth the meso-form of 2,3-butanediol was utilized together with acetoin. An attempt is made to explain these phenomena on the basis of the substrate specificity of the two enzymes which oxidize 2,3-butanediol in C. utilis. Although whole cells oxidized acetoin and diacetyl at high rates, attempts to identify the enzymes responsible for these oxidations were unsuccessful. In C. utilis and other yeasts metabolism of 2,3-butanediol probably involves a cleavage of the substrate into C2-units which are assimilated by the glyoxylate cycle. In the few yeasts which have been found to grow on 2,3-butanediol differences may be encountered with respect to the substrate specificity for the three stereoisomers of 2,3-butanediol. For example, Candida salmanticensis CBS 5121 showed no diauxis growth and utilized only two of three stereomers.
8 citations