Genetic characterization of a Sinorhizobium meliloti chromosomal region in lipopolysaccharide biosynthesis.

ABSTRACT: The genetic characterization of a 5.5-kb chromosomal region of Sinorhizobium meliloti 2011 that contains lpsB, a gene required for the normal development of symbiosis with Medicago spp., is presented. The nucleotide sequence of this DNA fragment revealed the presence of six genes: greA and lpsB, transcribed in the forward direction; and lpsE, lpsD, lpsC, and lrp, transcribed in the reverse direction. Except for lpsB, none of the lps genes were relevant for nodulation and nitrogen fixation. Analysis of the transcriptional organization of lpsB showed that greA and lpsB are part of separate transcriptional units, which is in agreement with the finding of a DNA stretch homologous to a "nonnitrogen" promoter consensus sequence between greA and lpsB. The opposite orientation of lpsB with respect

SUBMITTER: Lagares A 

PROVIDER: S-EPMC94998 | biostudies-literature | 2001 Feb

REPOSITORIES: biostudies-literature