PhrR-like gene praR of Azorhizobium caulinodans ORS571 is essential for symbiosis with Sesbania rostrata and is involved in expression of reb genes.

ABSTRACT: This study focuses on the function of the gene praR that encodes a putative transcription factor in Azorhizobium caulinodans ORS571, a microsymbiont of Sesbania rostrata. The praR gene is a homolog of the phrR gene of Sinorhizobium medicae WSM419, and the praR and phrR homologs are distributed throughout the class Alphaproteobacteria. The growth and nitrogen fixation activity of an A. caulinodans praR deletion mutant in the free-living state were not significantly different from those of the wild-type strain. However, the stem nodules formed by the praR mutant showed lower nitrogen fixation activity than the wild-type stem nodules. Microscopy revealed that infected host cells with an oval or elongated shape were observed at early stages in the nodules formed by the praR mutant, but these i

SUBMITTER: Akiba N 

PROVIDER: S-EPMC2876453 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature