Sequencing and Comparative Analysis of Flagellin Genes fliC , fljB , and flpA from Salmonella

Abstract

Salmonella isolates have traditionally been classified by serotyping, the serologic identification of two surface antigens, O-polysaccharide and flagellin protein. Serotyping has been of great value in understanding the epidemiology of Salmonella and investigating disease outbreaks; however, production and quality control of the hundreds of antisera required for serotyping is difficult and time-consuming. To circumvent the problems associated with antiserum production, we began the development of a system for determination of serotype in Salmonella based on DNA markers. To identify flagellar antigen-specific sequences, we sequenced 280 alleles of the three genes that are known to encode flagellin in Salmonella, fliC, fljB, and flpA, representing 67 flagellar antigen types. Analysis of the data indicated that the sequences from fliC, fljB, and flpA clustered by the antigen(s) they encode not by locus. The sequences grouped into four clusters based on their conserved regions. Three of the four clusters included multiple flagellar antigen types and were designated the G complex, the Z4 complex, and the ␣ cluster. The fourth cluster contained a single antigen type, H:z 29 . The amino acid sequences of the conserved regions within each cluster have greater than 95% amino acid identity, whereas the conserved regions differ substantially between clusters (75 to 85% identity). Substantial sequence heterogeneity existed between alleles encoding different flagellar antigens while alleles encoding the same flagellar antigen were homologous, suggesting that flagellin genes may be useful targets for the molecular determination of flagellar antigen type.

Development of a Novel Protein Microarray Method for Serotyping Salmonella enterica Strains

“…However, the PCR methods only detect a limited number of serovars at a time, and many different genetic markers are still to be developed or verified for identification of various serovars (8). In this research, a new antibody microarray-based assay that allows parallel analysis of multiple antigens was investigated for Salmonella serotyping.…”

Distribution Flagellin Gene Variants of Salmonella Typhi in Patients with Typhoid Fever in West Kutai, East Kalimantan, Indonesia

“…In most of Salmonella, there are two genes encode the flagella antigen, they are FliC and fljB. FliC gene can express two types of flagellin namely flagellin Hd and Hj [10].…”

Expressed and cryptic flagellin genes in the H44 and H55 type strains of Escherichia coli

“…In Salmonella, 114 different H antigens have been recognized and are known to be composed of combinations of 99 distinct antigenic factors (Popoff et al, 2003;McQuiston et al, 2004). Diphasic S. enterica strains have two flagellin genes, fliC and fljB, which specify different H antigens called phase 1 and phase 2, respectively.…”

“…Among the flagellin proteins from different H serotypes, the amino-acid sequences are well conserved in their N-and C-terminal regions, which bear the essential functions for protein export through the flagellumspecific type III secretion machinery and for polymerization into the filament (Mimori-Kiyosue et al, 1997;Samatey et al, 2001;Beatson et al, 2006). On the other hand, the central region is variable in length and aminoacid sequence and carries H serotype-specific epitopes (Reid at al., 1999;Wang et al, 2003;McQuiston et al, 2004).…”