A Functional Bacterium-to-Plant DNA Transfer Machinery of Rhizobium etli
نویسندگان
چکیده
Different strains and species of the soil phytopathogen Agrobacterium possess the ability to transfer and integrate a segment of DNA (T-DNA) into the genome of their eukaryotic hosts, which is mainly mediated by a set of virulence (vir) genes located on the bacterial Ti-plasmid that also contains the T-DNA. To date, Agrobacterium is considered to be unique in its capacity to mediate genetic transformation of eukaryotes. However, close homologs of the vir genes are encoded by the p42a plasmid of Rhizobium etli; this microorganism is related to Agrobacterium, but known only as a symbiotic bacterium that forms nitrogen-fixing nodules in several species of beans. Here, we show that R. etli can mediate functional DNA transfer and stable genetic transformation of plant cells, when provided with a plasmid containing a T-DNA segment. Thus, R. etli represents another bacterial species, besides Agrobacterium, that encodes a protein machinery for DNA transfer to eukaryotic cells and their subsequent genetic modification.
منابع مشابه
Transfer of DNA from Bacteria to Eukaryotes
Historically, the members of the Agrobacterium genus have been considered the only bacterial species naturally able to transfer and integrate DNA into the genomes of their eukaryotic hosts. Yet, increasing evidence suggests that this ability to genetically transform eukaryotic host cells might be more widespread in the bacterial world. Indeed, analyses of accumulating genomic data reveal cases ...
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