Photosynthesis gene superoperons in purple nonsulfur bacteria: the tip of the iceberg?

1992 ◽  
Vol 38 (1) ◽  
pp. 20-27 ◽  
Author(s):  
C. L. Wellington ◽  
C. E. Bauer ◽  
J. T. Beatty
Keyword(s):  
Key Words ◽  
Environmental Conditions ◽  
Rhodobacter Capsulatus ◽  
Protein Complexes ◽  
Photosynthetic Pigment ◽  
Purple Nonsulfur Bacteria ◽  
Pigment Protein Complexes ◽  
Photosynthesis Genes ◽  
Overlapping Transcription ◽  
Photosynthesis Gene

The purple, nonsulfur phototrophic bacterium Rhodobacter capsulatus has recently been found to contain several pigment biosynthetic operons that exhibit marked transcription read through into downstream operons that encode polypeptide components of photosynthetic pigment-protein complexes. This phenomenon has been found to be phenotypically significant for adaptation to changes in environmental conditions, and the term superoperon has been proposed to describe this sort of coupled transcriptional arrangement. We summarize the data that led to recognition of this novel transcriptional arrangement and suggest that superoperons might be more prevalent in prokaryotes than has heretofore been recognized. Key words: superoperons, overlapping transcription units, photosynthesis genes.

scholarly journals Effect of Oxygen on Translation and Posttranslational Steps in Expression of Photosynthesis Genes inRhodobacter capsulatus

1998 ◽  
Vol 180 (15) ◽  
pp. 3983-3987 ◽  
Author(s):  
Markus Hebermehl ◽  
Gabriele Klug
Keyword(s):  
Gene Expression ◽  
Oxygen Tension ◽  
Rhodobacter Capsulatus ◽  
Protein Complexes ◽  
Photosynthetic Apparatus ◽  
Regulatory Effect ◽  
Pigment Protein Complexes ◽  
Photosynthesis Genes ◽  
The Stability ◽  
Effect Of Oxygen

ABSTRACT The formation of the photosynthetic apparatus in Rhodobacter capsulatus is regulated by oxygen tension. Previous studies have shown a regulatory effect of oxygen on the transcription of photosynthesis genes and on the stability of certain mRNA segments. Here we show that oxygen affects puf and pucgene expression posttranslationally and that this regulation depends on the presence of bacteriochlorophyll. Our data suggest that this posttranslational effect of oxygen on puf andpuc expression is due to the primary effect of oxygen on bacteriochlorophyll synthesis or assembly of pigment protein complexes. Oxygen does not affect the rates of translation ofpuf-encoded proteins.

Two-photon excitation spectroscopy of photosynthetic light-harvesting complexes and pigments

2019 ◽  
Vol 216 ◽  
pp. 494-506 ◽  
Author(s):  
Alexander Betke ◽  
Heiko Lokstein
Keyword(s):  
Spectral Region ◽  
Protein Complexes ◽  
Photosynthetic Pigment ◽  
Photon Absorption ◽  
Light Harvesting Complexes ◽  
Two Photon Absorption ◽  
Two Photon ◽  
Photon Excitation ◽  
Pigment Protein Complexes ◽  
Two Photon Excitation

Two-photon excitation (TPE) profiles of LHCII samples containing different xanthophyll complements were measured in the presumed 11Ag− → 21Ag− (S0 → S1) transition region of xanthophylls. Additionally, TPE profiles of Chls a and b in solution and of WSCP, which does not contain carotenoids, were measured. The results indicate that direct two-photon absorption by Chls in the presumed S0 → S1 transition spectral region of carotenoids is dominant over that of carotenoids, with negligible contributions of the latter. These results suggest the re-evaluation of previously published TPE data obtained with photosynthetic pigment–protein complexes containing (B)Chls and carotenoids.

Redox Conditions Affect Ultrafast Exciton Transport in Photosynthetic Pigment–Protein Complexes

2017 ◽  
Vol 9 (1) ◽  
pp. 89-95 ◽  
Author(s):  
Marco A. Allodi ◽  
John P. Otto ◽  
Sara H. Sohail ◽  
Rafael G. Saer ◽  
Ryan E. Wood ◽  
...  
Keyword(s):  
Protein Complexes ◽  
Photosynthetic Pigment ◽  
Redox Conditions ◽  
Exciton Transport ◽  
Pigment Protein Complexes
Sign in / Sign up

Export Citation Format

Share Document