Construction, characterization, and complementation of Rhodospirillum rubrum puf region mutants. J Bacteriol 1991 Sep;173(18):5712-22
Date
09/01/1991Pubmed ID
1715861Pubmed Central ID
PMC208302DOI
10.1128/jb.173.18.5712-5722.1991Scopus ID
2-s2.0-0026014907 (requires institutional sign-in at Scopus site) 11 CitationsAbstract
Rhodospirillum rubrum is a facultatively phototrophic bacterium that, under certain growth conditions, forms an intracytoplasmic chromatophore membrane (ICM) housing the photochemical apparatus. The puf operon of R. rubrum encodes protein subunits of the photochemical reaction center and the B880 light-harvesting antenna complex. Mutant strains of R. rubrum were constructed by interposon mutagenesis through which a kanamycin resistance gene cartridge was inserted into restriction sites and in place of restriction fragments of the puf region. Southern blot analysis demonstrated that the defective copies of puf sequences had replaced their normal chromosomal counterparts through homologous recombination. The phenotypes of the mutant strains were evaluated on the basis of puf gene expression, spectral analysis, pigment content of membranes, and electron-microscopic examination of thin sections of cells grown under semi-aerobic and dark anaerobic conditions. Alterations of the puf region affect phototrophic competence and the formation of the ICM. The latter result implies an obligatory role for puf gene products in ICM formation in R. rubrum. One mutant with a deletion in puf structural genes was complemented in trans to the wild-type phenotype. Other mutants could be restored to the wild-type phenotype only by recombination.
Author List
Hessner MJ, Wejksnora PJ, Collins MLAuthor
Martin J. Hessner PhD Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Blotting, NorthernGene Expression
Genes, Bacterial
Genetic Complementation Test
Morphogenesis
Mutation
Photosynthesis
RNA, Bacterial
RNA, Messenger
Rhodospirillum rubrum
Spectrophotometry