Practical thin layer chromatography techniques for diaminopimelic acid and whole cell sugar analyses in the classification of environmental actinomycetes

Abstract

For the determination of diaminopimelic acid (DAP) stereoisomers in whole cell hydrolysates as chemotaxonomic markers of actinomycetes, two new pyridine-free solvent systems for TLC on cellulose sheets have been introduced: methanol/0.05 m potassium hydrogenphthalate buffer pH 4 2:1 (v/v) and methanol/0.12 M dimethylaminopyridine (DMAP) in H(2)O pH 6 2:1 (v/v). The commercial (Sigma) DAP standard can be separated by repeated TLC into its three stereoisomers. Addition of a single stereoisomer to the samples supported the detection (presence or absence) of the relevant stereoisomer by HPLC. In the study on whole cell sugars, TLC both on cellulose and on silica gel revealed to be successful in the separation of the components in modified pyridine-free solvent systems. The procedures of DAP and sugar analyses are summarized in two flow-charts.