IDENTIFICATION OF ORGANIC SOLUTES ACCUMULATED BY PURPLE AND GREEN SULFUR BACTERIA DURING OSMOTIC-STRESS USING NATURAL-ABUNDANCE C-13 NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY
Dt. Welsh et Ra. Herbert, IDENTIFICATION OF ORGANIC SOLUTES ACCUMULATED BY PURPLE AND GREEN SULFUR BACTERIA DURING OSMOTIC-STRESS USING NATURAL-ABUNDANCE C-13 NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY, FEMS microbiology, ecology, 13(2), 1993, pp. 145-149
Natural abundance C-13 NMR spectroscopy has identified sucrose and tre
halose as the principle compatible solutes accumulated by non-halophil
ic purple and green sulphur bacteria respectively, in response to osmo
tic stress. Synthesis of glycine betaine as a compatible solute was ra
re in non-halophilic phototrophic sulphur bacteria and appears to be l
imited almost exclusively to halotolerant isolates, although all isola
tes tested were able to accumulate exogenous glycine betaine from the
growth medium in response to osmotic stress. These data support the hy
pothesis that the degree of halotolerance of a microorganism may be du
e, at least in part, to the metabolic effects of the compatible solute
(s) accumulated.