Characterization of the Bradyrhizobium japonicum galE gene: its impact on lipopolysaccharide profile and nodulation of soybean.
The galE gene from Bradyrhizobium japonicum 61A101C, a soybean endosymbiont, was cloned and characterized. Its deduced amino-acid sequence showed a high similarity with that of other rhizobia. Functional identification of the galE gene was achieved by complementation of a galE mutant strain, PL2, with a series of pKM subclones. Disruption of the B. japonicum galE gene affects the lipopolysaccharide profile compared with that of the wild type, suggesting that galE is responsible for alteration of lipopolysaccharide structure. Examination of nodule formation by the wild-type and galE mutant revealed that the former displayed normal nodule development on soybean roots, whereas the latter showed no nodule formation at all time points examined except for 20 days after inoculation when <10% of soybean formed pseudo-nodules.
Chang
Woo-Suk
WS
National Center for Soybean Biotechnology and Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA. changwo@missouri.edu
Park
Kyoung-Min
KM
Koh
Sung-Cheol
SC
So
Jae-Seong
JS
D020369:Bradyrhizobium / Q000235:genetics / Q000502:physiology*; D008070:Lipopolysaccharides / Q000096:biosynthesis*; D009586:Nitrogen Fixation / Q000187:drug effects; D018517:Plant Roots / Q000254:growth & development* / Q000382:microbiology; D013025:Glycine max / Q000382:microbiology*
D008070:Lipopolysaccharides