1887

Abstract

The effect of the respiratory electron acceptor nitrous oxide on the synthesis of the photosynthetic apparatus of was examined. In phototrophically grown cells, the addition of nitrous oxide caused a reduction in the level of light-harvesting complex I and light-harvesting complex II under conditions of high light intensity (200 W m) and low light intensity (16 W m). 5-Aminolaevulinate synthase activity was decreased during growth in the presence of nitrous oxide and this limited production of spectral complexes since addition of exogenous 5-aminolaevulinic acid partially suppressed the effect of nitrous oxide. The effect of nitrous oxide on the expression of the operons encoding the pigment-binding proteins of light-harvesting complex I (), light-harvesting complex II () and the two isoenzymes of 5-aminolaevulinate synthase ( and ) were measured using transcriptional fusions to Nitrous oxide caused a decrease in and transcription. However, there was an apparent increase in the expression of and transcriptional fusions. The level of light-harvesting complexes in cells grown in the dark with different electron acceptors was also examined. Cells grown anaerobically with DMSO had a higher level of light-harvesting complexes than those grown anaerobically with nitrous oxide as electron acceptor. Cells grown aerobically had the lowest level of light-harvesting complexes. It is proposed that FnrL-dependent and FnrL-independent expression of photosynthesis genes is modulated by redox changes elicited by nitrous oxide respiration.

Loading

Article metrics loading...

/content/journal/micro/10.1099/13500872-142-10-2831
1996-10-01
2019-10-23
Loading full text...

Full text loading...

http://instance.metastore.ingenta.com/content/journal/micro/10.1099/13500872-142-10-2831
Loading
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error