INTRODUCTION

() is a member of in family Pasteurellaceae. It is the causative agent of porcine pleuropneumonia, which has caused huge economic losses to pig industry over the world. Cysteine is a precursor of many important biomolecules and defense compounds in the cell. However, molecular mechanisms of cysteine transport in are unclear.

METHODS

In this study, gene-deleted mutants were generated and investigated, to reveal the roles of potential cysteine/cystine transport proteins FliY and YdjN of .

RESULTS

Our results indicated that the growth of was not affected after or single gene deletion, but absence of both FliY and YdjN decreased the growth ability significantly, when cultured in the chemically defined medium (CDM) supplemented with cysteine or cystine as the only sulfur source. double deletion mutant ΔΔ showed increased sensitivity to oxidative stress. Besides, -complementation of YdjN into ΔΔ and wild type leads to increased biofilm formation in CDM. However, the virulence of ΔΔ was not attenuated in mice or pigs.

DISCUSSION

These findings suggest that FliY and YdjN are involved in the cysteine/cystine acquisition, oxidative tolerance, and biofilm formation, but not contribute to the pathogenicity of .