Virulence regulation of Znuptake systemon mesophilicSRW-OG1.

Abstract

Psychrophiliccould not grow above 25°C and therefore thought unable to infect mammals and humans. In our previous study, a mesophilicSRW-OG1 was isolated fromwith furunculosis. Through the analysis of preliminary RNA-seq, it was found that the Znuptake related genesandmight be involved in the virulence regulation ofSRW-OG1. Therefore, the purpose of this study was to explore the effect ofsilencing on the virulence regulation ofSRW-OG1. The results showed that the growth of the-RNAi,-RNAi, and-RNAi strains was severely restricted under the Festarvation, but surprisingly there was no significant difference under the Znrestriction. In the absence of Znand Fe, the expression level ofwas significantly increased. The motility, biofilm formation, adhesion and hemolysis of the-RNAi,-RNAi, and-RNAi strains were significantly reduced. We also detected the expression ofunder different growth periods, temperatures, pH, as well as Cuand Pbstresses. The results showed thatwas significantly up-regulated in the logarithmic phase and the decline phase of. Interestingly, the trend of expression levels of theat 18, 28, and 37°C was reversed to another Znuptake related gene. Taken together, these indicated that thewas necessary forSRW-OG1 pathogenicity and environmental adaptability, and was cross regulated by iron starvation, but it was not irreplaceable forSRW-OG1 Znuptake in the host.