Identification of a novel @entity16258 nodulation efficiency nfe gene homolog of XXXX @entity7222 cyclodeaminase.

@entity3261 @entity535 @entity7222 @entity1521 @entity16258
The nfe genes located on the large plasmid pRmeGR4b are involved in the nodulation efficiency and competitiveness of @entity16258 GR4 on alfalfa roots. One hundred twenty-eight base-pairs downstream of nfe2 gene we found an open reading frame designated ORFC, 970 bp long and potentially coding for a 320 @entity535 long protein. The @entity535 sequence of the putatively encoded ORFC product shows similarity with @entity7222 cyclodeaminase (OCD) of @entity3261 an unusual enzyme that converts @entity7222 into @entity1521 . The gene product of ORFC was identified as a 37-kDa protein by in vitro-coupled transcription-translation and in vivo by the T7 RNA polymerase/promoter system. DNA hybridization studies showed that strain GR4 carries a single copy of the ocd-like gene. No homologous sequences to GR4 ORFC DNA were found in other @entity16258 strains or Rhizobium spp. assayed. Furthermore, a GR4 derivative mutant obtained by plasmid disruption of ORFC showed an impaired nodulation efficiency as compared to that of the wild-type strain GR4. Thus, the former locus should be considered a novel nfe gene. We propose to rename the nfe genes, nfe1, 2 and ORFC as nfeA, B, and D, respectively.
