Pre-exposure to UV irradiation increases the transfer frequency of the IncJ conjugative transposon-like elements R391, R392, R705, R706, R997 and pMERPH and is recA+ dependent.
The enteric conjugative transposon-like IncJ elements R391, R392, R705, R706 and pMERPH, all demonstrated increased conjugative transfer upon UV irradiation. The transfer frequency increased on average from its basal rate of 10(-5) to 10(-3) per recipient, upon pre-exposure to UV irradiation. However, the transfer frequency of R997, which was higher than the other IncJ elements at 10(-3) per donor, showed a smaller increase. This effect was shown to be recA+ dependent in all cases. Using PCR primers directed outwards from the ends of the integrated R391 element it was observed that a circular intermediate of the element forms within the host, which has been proposed to be a transfer intermediate. Using real-time PCR, it was determined that the amount of the circular intermediate produced increased substantially upon UV irradiation.
McGrath
Barry M
BM
Molecular Biochemistry Laboratory, Department of Chemical and Environmental Sciences, Industrial Biochemistry Programme, University of Limerick, Limerick, Ireland.
O'Halloran
John A
JA
Pembroke
J Tony
JT
D003227:Conjugation, Genetic / Q000528:radiation effects*; D004251:DNA Transposable Elements / Q000235:genetics* / Q000528:radiation effects*; D004755:Enterobacteriaceae / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011938:Rec A Recombinases / Q000378:metabolism; D014466:Ultraviolet Rays
D004251:DNA Transposable Elements; D011938:Rec A Recombinases