AEM
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Schofield, P. R.
Right arrow Articles by Watson, J. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Schofield, P. R.
Right arrow Articles by Watson, J. M.
Agricola
Right arrow Articles by Schofield, P. R.
Right arrow Articles by Watson, J. M.

 Previous Article  |  Next Article 

Appl Environ Microbiol. 1987 December; 53(12): 2942-2947
Copyright © 1987, American Society for Microbiology. All Rights Reserved.

Evidence for Genetic Exchange and Recombination of Rhizobium Symbiotic Plasmids in a Soil Population

Peter R. Schofield{dagger}, Alan H. Gibson, William F. Dudman and John M. Watson*

Commonwealth Scientific and Industrial Research Organisation Division of Plant Industry, Canberra City 2601, Australia

ABSTRACT

A soil population of 16 Rhizobium leguminosarum bv. trifolii isolates was characterized by using three Sym (for symbiotic) plasmid-specific DNA hybridization probes: (i) an R. leguminosarum bv. trifolii-specific, repeated-sequence probe; (ii) a nifHDK gene probe, and (iii) a nod gene probe. A predominant Sym plasmid family was identified among the isolates. Three other unrelated Sym plasmid families were also identified. The isolates were also classified either by using a chromosomal DNA hybridization probe or by serological relatedness to 25 different R. leguminosarum bv. trifolii antisera. With either method, it was possible to group the 16 soil isolates into identical or related families. However, the correlation between the two techniques was not high. Irrespective of the means used to classify the bacterial host strain, it was possible to identify the same Sym plasmids in unrelated strains, as well as unrelated Sym plasmids in identical host strains. These data indicate that, within this soil population, there has been genetic exchange of Sym plasmids, and in one instance the hybridization pattern indicates that in vivo recombination of two different Sym plasmids may have occurred. Symbiotic effectiveness tests on red, strawberry, and subterranean clovers clearly differentiated the isolates. In general, the pattern of response was similar within groupings on the basis of Sym plasmid and chromosomal profiles but different between such groups.


FOOTNOTES

* Corresponding author.

{dagger} Present address: Laboratory of Molecular Neuroendocrinology, ZmbH, Universität Heidelberg, D-6900 Heidelberg, Federal Republic of Germany.


Appl Environ Microbiol. 1987 December; 53(12): 2942-2947
Copyright © 1987, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Microbiol. Mol. Biol. Rev. Eukaryot. Cell All ASM Journals

Copyright © 1987 by the American Society for Microbiology. All rights reserved.