Microbial chemotaxonomy. Chromatography, electrophoresis and relevant profiling techniques.

This review deals with the chemistry of marker substances used in microbial classification and identification, their isolation and purification and their biomedical application. A critical evaluation of current methods is also included. The information presented is partly based on personal experience, partly derived from more than 300 publications in this rapidly expanding field of science. Much has been done to improve the recognition of microorganisms by GC, but there are also a series of other techniques available that can assist in bacterial classification and identification. Some of these techniques have been made available to the clinical microbiologist through commercial systems, e.g., assessment of bacterial fatty acids. A fingerprint library has been developed by Hewlett-Packard for the analysis of fatty acids from approximately 6000 different bacteria. Other chemotaxonomic methods require great personal expertise and advanced equipment. Efforts should therefore be made to adapt and simplify such methods for application in the routine clinical laboratory. Chemical markers will probably have a great impact on future microbial taxonomy, particularly in cases where conventional methods fail to give satisfactory classifications. In order to make taxonomy more objective, there seems to be a need for screening of chemical markers in bacterial species and for compiling chemotaxonomic fingerprints in clinical manuals.