ISSN:
1432-072X
Keywords:
Photosynthetic bacteria
;
Rhodobacter capsulatus (Rhodopseudomonas capsulata)
;
Cryptic plasmid
;
DNA-DNA hybridization
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Phodobacter capsulatus (formerly Rhodopseudomonas capsulata) strain B10 was found to contain a single plasmid of molecular weight 86×106. Strains lacking this plasmids were isolated by various methods from strains containing the mutant R plasmid, pTH10. With the exception of two strains, which were found to contain chromosomal insertions of R plasmid DNA, strains lacking the endogenous plasmid appeared to be unaffected in any of the following metabolic or genetic functions: photosynthetic, autotrophic, diazotrophic, and dark, anaerobic growth; the production of bacteriocin; homologous recombination; the restriction of foreign DNA; and the production of gene transfer agent. DNA-DNA hybridization experiments confirmed that the plasmid had been eliminated from these strains and not become integrated into the chromose. However, sequences homologous to those of the endogenous plasmid were found to be present in the chromosome of R. capsulatus B10. This suggests, among other possibilities, that the endogenous plasmid may have originated in the chromosome, and might serve to duplicate certain chromosomal functions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00415274
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