ISSN:
1432-072X
Keywords:
Membrane Differentiation
;
Reaction Center
;
Bacteriochlorophyll
;
Antenna-Pigment Complex
;
Bacteriochlorophyll-Protein Association
;
Photosynthetic Bacteria
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Formation of the photosynthetic apparatus was induced in aerobically grown dark cultures of Rhodopseudomonas capsulata by lowering of the oxygen tension. Besides the wild type strain the carotenoid-less mutant strain A1a+ was investigated. Both strains exhibited initially a decrease of the molar ratio of total bacteriochlorophyll (Bchl) to reaction center (RC) Bchl, followed by an increase. Synthesis of RC-Bchl preceded the synthesis of light-harvesting (LH) Bchl. Activities of photophosphorylation in membrane preparations, isolated from cultures after different periods of incubation at low aeration, decreased on the basis of total Bchl from about 9 to 2 μmole ATP/μmole total Bchl·min, whereas the rate on the basis of RC-Bchl remained constant (about 500 μmole ATP/μmole RC-Bchl·min). Under the same conditions the membrane proteins were labelled with U−14C-protein hydrolysate. Corresponding to RC-Bchl the synthesis of RC-proteins dominated during the first 30 min of incubation at pO2 below 3 mmHg. After 45–60 min of membrane formation at low aeration the synthesis of LH-complex proteins exceeded the synthesis of RC proteins. The correlations between protein and Bchl synthesis in the sequential formation of RC- and LH-complexes are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00447303
