LINEAR AND CIRCULAR DICHROISM OF MEMBRANES FROM RHODOPSEUDOMONAS CAPSULATA

Journal Article · Wed Oct 01 04:00:00 EDT 1980 · Biochimica et Biophysica Acta

OSTI ID:1090452

Bolt, John D.; Sauer, Kenneth; Shiozawa, Judith A.; Drews, Gerhart

Absorption, linear dichroism and circular dichroism spectra of Rhodopseudomonas capsulate (wild-type - St. Louis strain, mutant Y5 and mutant A1a{sup +}) are particularly sensitive to the nature of the light-harvesting bacteriochlorophyll-carotenoid-protein complexes. Evidence for exciton-type interactions is seen near 855 nm in the membranes from the wild-type and from mutant Y5, as well as in an isolated B800+850 light-harvesting complex from mutant Y5. The strong circular dichroism that reflects these interactions is attenuated more than 10-fold in membranes from the A1a+ mutant, which lacks both B800+850 and colored carotenoids and contains only the B875 light-harvesting complex. These results lead to the conclusion that these two light-harvesting complexes have significantly different chromophore arrangements or local environments.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: Chemical Sciences Division
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 1090452
• Report Number(s): LBL-11757
• Journal Information: Biochimica et Biophysica Acta, Journal Name: Biochimica et Biophysica Acta
• Country of Publication: United States
• Language: English

Related Subjects

light-harvesting pigment-protein
(Rps. capsulata)
59 BASIC BIOLOGICAL SCIENCES
Bacteriochlorophyll
Photosynthetic bacteria