Iron is an essential element for living organisms that plays critical roles in the process of bacterial growth and metabolism.However,it remains to be elucidated whether piuB encoding iron-uptake factor is involved in iron uptake and pathogenicity of Xanthomonas axonopodis pv.glycines(Xag).To investigate the function of piuB,we firstly generated a piuB deletion mutant(ΔpiuB)by homologous recombination.Compared with the wild-type,the piuB mutant exhibited significantly reduced growth and virulence in host soybean.The mutant displayed markedly increased siderophore secretory volume,and its sensitivity to Fe3+,Cu2+,Zn2+and Mn2+was significantly enhanced.Additionally,the H2O2 resistance,exopolysaccharide yield,biofilm formation,and cell mobility of ΔpiuB were significantly diminished compared to that of the wild-type.The addition of exogenous Fe3+cannot effectively restore the above characteristics of ΔpiuB.However,expressing piuB in trans rescued the properties lost by ΔpiuB to the levels in the wild-type.Taken together,our results demonstrated that PiuB is a potential factor for Xag to assimilate Fe3+,and is necessary for Xag to be pathogenic in host soybean.
维普
万方数据