Effect of short-chain fatty acids on the size of enteric bacteria

Abstract

The size of Escherichia coli and Salmonella enteritidis PT4 cells was measured using both transmission electron micrographs and image analysis. Incubation in the presence of formic and propionic acids resulted in larger cells, possibly as a result of DNA inhibition, with no apparent damage to the cell membranes. Bacteria incubated with propionic acid were more resistant to shrinkage after fixation, possibly as a result of altered phospholipid and fatty acid composition.