摘要：SummaryRoot colonization by beneficial rhizobacteria determines their plant beneficial effects. The messenger c-di-GMP is involved in the bacterial transition process between motility and biofilm, which are crucial to the colonization ability of the rhizobacteria. In this study, we identified three GGDEF domain-containing proteins (YdaK, YhcK, and YtrP) and two EAL domain-containing proteins (YuxH and YkuI) in beneficial rhizobacteriumBacillus velezensisSQR9. We found that deficiency ofytrPorykuIin SQR9 led to impaired biofilm formation, while deficiency ofyuxHled to weakened motility. Further investigation showed that YtrP, YuxH, and YkuI all contributed to the root colonization of SQR9 on cucumber root. Further bioinformatics analysis showed that YtrP and YuxH are conserved in plant beneficialBacillusgroup, while they do not occur in animal pathogenicBacillus. This research will be useful for enhancing the beneficial function ofBacillusspp. in agricultural application.Graphical abstractDisplay OmittedHighlights•C-di-GMP is involved in root colonization ofB. velezensis•YtrP and YkuI enhance the root colonization by regulating biofilm ofB velezensis•YuxH enhances the root colonization by affecting the motility ofB. velezensis•YtrP and YuxH are conserved in plant beneficialBacillusgroupMicrobiology; Microbiofilms; Plant biology; Interaction of plants with organisms; Plant physiology
