Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023241 (Legionella)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In experiments on conjugation the transfer of a number of R-plasmids having a wide range of hosts, such as plasmids RP1, R68.45, RP4, N3, RK2, S-a, those having a narrow range of hosts, such as plasmid R64, to strains of different Legionella species was shown. The frequency of transfer varied from 3.1 X 10(-3) to 9.4 X 10(-7). The fact that the conjugation transfer was confirmed by the reverse transfer of plasmids from Legionella transconjugates to Escherichia coli strain K12, as well as by the detection of the DNA of the transferred plasmid by means of electrophoresis in agar gel. Plasmid RP1 showed different behavior in transconjugates of various Legionella species after several passages in a medium free of antibiotics. In the Legionella strain under study the unstable preservation of plasmid R64 was observed.
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PMID:[The conjugational transfer of plasmids to Legionella strains]. 218 66

Genetic exchange mechanisms, to our knowledge, have not been reported for Legionella pneumophila, and consequently, studies on the genetic organization of L. pneumophila have not appeared in the literature. Here, we describe gene transfer mediated by broad host range conjugative plasmids in Legionella spp. Escherichia coli strains carrying plasmids RP1 and R68.45 (IncP1), S-a (IncW), and R40a (IncC), but not plasmids of incompatibility groups FI, FII, and FV, served as donors in matings with L. pneumophila Knoxville 1 (LPK-1). Transconjugants selected by resistance to kanamycin (RP1, R68.45, and S-a) and carbenicillin (R40a) were observed at frequencies of 6.6 X 10(-3), 4.7 X 10(-3), 2.2 X 10(-4), and 5.4 X 10(-5), respectively. Plasmid transfer was not affected by DNase added to the mating medium. After plasmid transfer, LPK-1 stably maintained RP1, R68.45, and S-a, but not R40a. Plasmid-containing LPK-1 isolates also served as donors in agar plate matings with E. coli W1485-1 and naladixic acid-resistant mutants of LPK-1, Legionella micdadei, and Legionella longbeachii. Recombinational exchange of a chromosomal trait was demonstrated when a thymidine auxotroph of L. pneumophila was repaired by R68.45-mediated chromosomal mobilization of a prototrophic donor strain.
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PMID:Conjugation-mediated genetic exchange in Legionella pneumophila. 388