PHOSPHOLIPIDS AND SULFOLIPIDS AS BIOMARKERS OF CAULOBACTER-SENSU-LATO, BREVUNDIMONAS AND HYPHOMONAS

Phospholipids of type strains and isolates of Caulobacter, Brevundimon as, Hyphomonas and Mycoplana bullata were studied bu chromatographic a nd spectroscopic methods. Using tandem mass spectrometry individual ph ospholipids were analyzed and their structures elucidated. From the 69 strains included in this study 26 new phosphoglucolipids and two new sulfoquinovosyl-diacylglycerols could be identified. While more than 3 0 different fatty acids were found in the phospholipid fraction of Cau lobacter and Brevundimonas only seven different fatty acids occur with in the 26 different phosphoglucolipids identified. The distribution of the different types of phospholipids, especially of the sulfoquinovos yl-. glucoronotaurine amide- and phosphatidyl-glucopyranosyl-diacylgly cerols, leads to the identification of four different phenotypic group s of these bacteria in agreement with the phylogeny published by STAHL et al. in 1992. One comprises Caulobacter sensu stricto with the type strain C. vibrioides, the second the type strains of Brevundimonas to gether with a considerable number of Caulobacter species and the third the halophilic Caulobacter spp. around C. maris. The latter group lac ks the phosphatidyl-glucopyranosyl-diacylglycerols but contains sulfoq uinovosyl- and glucuronotaurine amide diacylglycerols. They can be dis cerned from Hyphomonas by the occurrence of sulfoquinovosyl-diacylglyc erols which are absent in strains of the genus Hyphomonas.