Functional analysis of motA gene in Azorhizobium caulinodans ORS571

Abstract:

[Objective] MotA, an important flagellar motor protein regulating flagellar motility, is one of components of transmembrane proton channel. In this study, we explored the role of motA in Azorhizobium caulinodans ORS571 in the free-living and symbiotic states. [Methods] ∆motA mutant was constructed by homologous recombination and tri-parental conjugation. We tested the characterizations of the growth state, swimming motility, nitrogen fixation, exopolysaccharides (EPS) production, biofilm formation, and host colonization between wild-type and ∆motA mutant. [Results] ∆motA mutant showed defective cell motility ability but the growth property was not impaired, and its nitrogen fixation, EPS production, biofilm formation, and host colonization were lower than that of the wild-type. [Conclusion] In A. caulinodans ORS571, MotA plays role in motility, nitrogen fixation, EPS production, biofilm formation, and root colonization.

Key words:Azorhizobium caulinodans ORS571;flagellar motor protein;motA