RT Journal Article SR Electronic(1) A1 Laeremans, T. A1 Coolsaet, N. A1 Verreth, C. A1 Snoeck, C. A1 Hellings, N. A1 Vanderleyden, J. A1 Martínez-Romero, E.YR 1997 T1 Functional redundancy of genes for sulphate activation enzymes in Rhizobium sp. BR816 JF Microbiology, VO 143 IS 12 SP 3933 OP 3942 DO https://doi.org/10.1099/00221287-143-12-3933 PB Microbiology Society, SN 1465-2080, AB The broad-host-range, heat-tolerant Rhizobium strain BR816 produces sulphated Nod metabolites. Two ORFs highly homologous to the Sinorhizobium meliloti nodPQ genes were isolated and sequenced. It was found that Rhizobium sp. BR816 contained two copies of these genes; one copy was localized on the symbiotic plasmid, the other on the megaplasmid. Both nodP genes were interrupted by insertion of antibiotic resistance cassettes, thus constructing a double nodP1P2 mutant strain. However, no detectable differences in Nod factor TILC profile from this mutant were observed as compared to the wild-type strain. Additionally, plant inoculation experiments did not reveal differences between the mutant strain and the wild-type. It is proposed that a third, functionally homologous locus complements mutations in the Nod factor sulphation genes. Southern blot analysis suggested that this locus contains genes necessary for the sulphation of amino acids., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-143-12-3933