Fatty acid profiles in pigmented and non-pigmented strains of S-marcescens

Wild, pigmented strains of Serratia marcescens and their non-pigmented muta nts were compared on the basis of fatty acid profiles and lipid content. Cl assic biochemical tests show only minor differences, as well as fatty acid ratio C18:C16. The total amount of lipid synthesized and the saturated/unsaturated fatty a cids ratio disclose a sharp total lipid reduction and a high percentage of unsaturated fatty acids in the pigmented strains, placing them in separated clusters compared with the nonpigmented mutants. It is hypothesized that the synthesis of the polyacetate required for the c ompletion of the prodigiosin molecule may result in a waste of methyl group s and thus affect the total amount of lipids.