Lipopolysaccharides (LPSs), isolated from four
Aquaspirillum species, i.e. the type strains of
A. itersonii subsp.
nipponicum, A. polymorphum, A.
aquaticum and
A. metamorphum together with
A. metamorphum mutant strain 12-3 were characterized onto their chemical composition.
A.
itersonii subsp.
nipponicum IFO 13615 and
A. polymorphum IFO 13961, both belonging to the α-1 subgroup of
Proteobacteria, possess L-glycero-D- manno-heptose, glucuronic acid and galacturonic acid in their LPS and both have 3-hydroxy-tetradecanoic acid as hydroxylated fatty acid.
A.
itersonii subsp.
nipponicum has additionally 3-hydroxy-hexadecanoic acid and a small amount of 3-hydroxy-octadecanoic acid. In the LPSs of
A.
aquaticum IFO 14918 and both
A. metamorphum IFO 13960 strains, which belong to the β-1 subgroup of
Proteobacteria, neither heptoses nor uronic acids could be detected. The main sugar components were rhamnose and glucose and both possess the same three major fatty acid constituents dodecanoic acid, tetradecanoic acid and 3-hydroxydecanoic acid. From the DOC-PAGE pattern it was evident that
A. itersonii subsp.
nipponicum and
A. polymorphum have a similar LPS-type as revealed for two
Rhodospirillum strains,
R. fulvum DSM 117 and
R. molischianum NTHC 131. These strains being members of the α-1 group of
Proteobacteria possess LPSs which show distinct gaps between the band of R-type LPS and other slower-moving bands. In the case of
A. metamorphum such gap was also visible. The LPS of
A. aquaticum showed R-type character on DOC-PAGE.
View full abstract