Inactivation of the nodH gene in Sinorhizobium sp. BR816 enhances symbiosis with Phaseolus vulgaris L.
Sulfate modification on Rhizobium Nod factor signaling molecules is not a prerequisite for successful symbiosis with the common bean (Phaseolus vulgaris L.). However, many bean-nodulating rhizobia, including the broad host strain Sinorhizobium sp. BR816, produce sulfated Nod factors. Here, we show that the nodH gene, encoding a sulfotransferase, is responsible for the transfer of sulfate to the Nod factor backbone in Sinorhizobium sp. BR816, as was shown for other rhizobia. Interestingly, inactivation of nodH enables inoculated bean plants to fix significantly more nitrogen under different experimental setups. Our studies show that nodH in the wild-type strain is still expressed during the later stages of symbiosis. This is the first report on enhanced nitrogen fixation by blocking Nod factor sulfation.
Remans
Roseline
R
Centre of Microbial and Plant Genetics, Kasteelpark Arenberg, Heverlee, Belgium.
Snoeck
Carla
C
Verreth
Christel
C
Croonenborghs
Anja
A
Luyten
Ellen
E
Ndayizeye
Maxime
M
Martínez-Romero
Esperanza
E
Michiels
Jan
J
Vanderleyden
Jos
J
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D005810:Multigene Family; D009154:Mutation; D009586:Nitrogen Fixation / Q000235:genetics; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D027805:Phaseolus / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D053204:Root Nodules, Plant / Q000235:genetics / Q000382:microbiology / Q000648:ultrastructure; D020579:Sinorhizobium / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D015238:Sulfotransferases / Q000235:genetics* / Q000378:metabolism; D013559:Symbiosis / Q000235:genetics*
D001426:Bacterial Proteins; D010088:Oxidoreductases; C029130:nitrogenase reductase; C092976:NodH protein, Sinorhizobium meliloti; D015238:Sulfotransferases