rptA, a novel gene from Ensifer (Sinorhizobium) meliloti involved in conjugal transfer

PISTORIO M.; TORRES TEJERIZO G. A.; DEL PAPA M. F.; GIUSTI M. A.; LOZANO M. J.; LAGARES A.

FEMS MICROBIOLOGY LETTERS

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2013 vol. 345 p. 22 - 30

0378-1097

We approached the identification of Ensifer (Sinorhizobium) meliloti conjugalfunctions by random Tn5-B13 mutagenesis of the pSmeLPU88a plasmid ofE. meliloti strain LPU88 and the subsequent selection of those mutants thathad lost the ability to mobilize the small plasmid pSmeLPU88b. The Tn5-B13-insertion site of one of the mutants was cloned as an EcoRI-restricted DNAfragment that after subsequent isolation and sequencing demonstrated that asmall open reading frame of 522 bp (designated rptA, for rhizobium plasmidtransfer A) had been disrupted. The predicted gene product encoded by therptA sequence shows a significant similarity to two hypothetical proteins of theplasmid pSmed03 of Ensifer medicae WSM419 and other rhizobia plasmids. Nosignificant similarity was found to any protein sequence of known functionregistered in the databases. Although the rptA gene was required for pSmeLPU88b-plasmid mobilization in the strain 2011 background, it was notrequired in the original strain LPU88 background.