Effects of different culture media and oxygen upon lipids of<i>Escherichia coli</i> K‐12

Abstract

Abstract The effects of altering the chemical composition of the culture media and the oxygen content of the environment upon the lipid metabolism of Escherichia coli K‐12 were investigated. When E. coli cells were grown on the same culture medium but under aerobic and anaerobic conditions, an increase in the free fatty acids of anaerobically grown cells was observed with a disproportionate increase in the unsaturated fatty acids. When glucose was the sole carbon source, both fatty alcohols and hydrocarbons were detected as component lipids of these cells, whether growth occurred under aerobic or anaerobic conditions. Based upon this observation, acetate is considered the initial precursor for fatty alcohol and hydrocarbon biosynthesis. A possible metabolic pathway involving fatty alcohols in hydrocarbon synthesis has been postulated.