Article Abstract:
Strain N4 of Sinorhizobium meliloti contains a Tn5luxAB insertion in a gene, identified as hmgA, which is induced by carbon and nitrogen deprivation as well as in the presence of tyrosine. The Tn5luxAB-targeted locus shares significant similarity with the human hmgA gene and the corresponding Aspergillus nidulans gene, encoding the enzyme homogentisate dioxygenase, which is involved in tyrosine degradation. Strain N4 was not capable of using tyrosine as carbon source and producing a melanin-like pigment. In addition, it lacked homogentisate dioxygenase activity and was not affected in stationary-phase survival.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
The Rhizobium (R.) meliloti strain 042B, from alfalfa grown in the Xinjiang Autonomous Region of China can nodulate and fix nitrogen with soybean plants indicating that the symbiotic capabilities of R. meliloti are not restricted to alfalfa and other legumes. R. strains generally form nodules only on a selected range of host plants though the host specificity varies in different strains. The R. meliloti strain can fix more nitrogen per hectare than other rhizobia including soybean rhizobia.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
The effect of inactivated nolX on symbiotic properties was studied on the three Rhizobium fredii strains, namely, USDA191, USDA257 and HH103. Inactivation of nolX lead retarded initial nodulation rates on the soybean cultivars. Nodulation of two Erythrina species, however, was blocked if nolX was present but was allowed to proceed when the gene was inactivated. NolX revealed to have dual function and was concluded to be of symbiotic significance in all the three strains.
User Contributions:
Comment about this article or add new information about this topic: