Fatty acid composition of bacteria as a chemotaxonomic criterion.

The paper reviews data on the fatty acid composition of bacteria as a taxonomic criterion useful for the identification of bacteria and specifying their classification. Variations in the fatty acid composition of bacteria associated with culturing conditions and due largely to the adaptive role of fatty acids in the bacterial cell require that standard conditions be maintained while examining that character. In some cases, adjustment of culturing conditions may be a factor providing for the identification of specificities in the fatty acid profile of bacteria of related species. The use of data on the fatty acid composition of bacteria has promising applications in confirming and establishing their phylogenetic relationship, that being accomplished not only on the basis of similarity in the character under consideration which correlates with similarity in genotypic and other phenotypic characters, but by analyzing its adaptive variability as well. The latter approach is especially promising for creating a natural classification. It is pointed out that the determination of the fatty acid composition of the lipid component of lipopolysaccharides from Gram-negative bacteria is useful as it supplies additional taxonomic information.