Mixotrophic growth of bacteriochlorophyll a -containing members of the OM60/NOR5 clade of marine gammaproteobacteria is carbon-starvation independent and correlates with the type of carbon source and oxygen availability

摘要: Background: Populations of aerobic anoxygenic photoheterotrophic bacteria in marine environments are dominated by members the Roseobacter lineage within Alphaproteobacteria and OM60/NOR5 clade gammaproteobacteria. A wealth information exists about regulation pigment production mixotrophic growth various clade, but a detailed knowledge bacteriochlorophyll a-containing gammaproteobacteria is still limited to one strain species Congregibacter litoralis. Results: The photosynthetic pigments light-dependent was analysed Luminiphilus syltensis DSM 22749 T , Chromatocurvus halotolerans 23344 Pseudohaliea rubra 19751 representing three taxonomically diverse strains affiliated clade. In these expression apparatus depended mainly on type carbon source availability oxygen. effect illumination varied significantly between strains. contrast halotolerans, repressed light moderate intensities, probably indicating higher sensitivity light-induced oxidative stress. efficiency using for did not correlate with cellular level pigments, metabolized substrate malate being optimal most cases. Conclusions: Oligotrophic conditions or limitation were required ability as energy fine tuning photosynthesis gene oxygen availability, which indicates that controlled redox state. While has main impact representatives this case