Title: Role of flgA for Flagellar Biosynthesis and Biofilm Formation of Campylobacter jejuni NCTC11168
Abstract: IntroductionCampylobacter jejuni is one of the most common foodborne pathogenic bacteria worldwide.Consumption of poultry, especially chickens, is considered the most common route for human infections of C. jejuni [11,34].C. jejuni is microaerophilic and susceptible to relatively high oxygen concentrations under normal atmosphere.However, it often confronts and can survive the aerobic conditions that are common in food-associated environments to infect humans.It strongly suggests that C. jejuni should have developed several strategies to overcome the obstacles of those conditions [2,20].Biofilm formation is considered as one of the important survival strategies bacterial pathogens employ to survive harsh environmental conditions such as acids, metal toxicity, sanitizers, antibiotics, and antimicrobial agents [10,16,18,20,29].It is a biologically active matrix in which bacterial cells are embedded with a self-produced polymeric exopolysaccharide substance [5].Antimicrobials such as sanitizers may not easily penetrate the three-dimensional matrix and reach the microbial cells embedded in the matrix [16].Thus, the biofilms formed by foodborne pathogens are more likely to survive the harsh environmental conditions compared with planktonic cells.They can impose a significant threat on public health because microbial cells encased in biofilms can contaminate food products such as in food processing facilities.C. jejuni has the flagellar apparatus enabling the bacterium to move freely, which is important for its survival in the environment and the colonization of animal host.The flagella have the functions of not only motility but also the secretion of proteins involved in pathogenesis [1,15,27].C. jejuni can also form biofilms on various abiotic surfaces such as stainless steel, glass, and plastic [12].The biofilm is considered to be a potential strategy that C. jejuni,