Comparison of carbon metabolism between chloramphenicol-treated and untreated cultures of Clostridium acetobutylicum

Abstract

Carbon distribution from substrates to products in Clostridium acetobutylicum ATCC 824 was investigated by adding 14C-labeled substrates as tracers. Comparison of carbon conversion between chloramphenicol (CAP)-treated and untreated cultures was also studied. The percentage of 14C recovery in butanol, acetone and ethanol from uniformly labeled [14C]glucose was increased by 17, 25 and 30%, respectively, after CAP addition. The incorporation of 14C in solvents from 14C-labeled acetate and butyrate was also increased by the antibiotic treatment. A total ~4C recovery of 12°70 in all the products from added [14C]Na2CO3 indicates significant heterotrophic CO2 fixation in this microorganism. The ratio of carbon in butanol derived from glucose, acetate and butyrate was about 71:6: 18, and this ratio was unchanged by CAP treatment.