Cloning and nucleotide sequence of a flagellin-coding gene (hag) from Serratia marcescens 274

The pigmented enterobacterium Serratia marcescens shows a high frequency of color variation. In strain 274, color variation was shown to be closely associated with flagellar variation [Paruchuri and Harshey, J. Bacteriol. 169 (1987) 61-65]. As a first step towards understanding the genetic basis of this phenomenon, we have cloned and sequenced a flagellin-coding gene of S. marcescens 274. The gene codes for a protein product of 351 aa, with a predicted Mr of 36,862. Amino acid sequence comparisons reveal a high degree of homology between the N-terminal half and C-terminal third of the Serratia flagellin and flagellins from Escherichia coli and Salmonella typhimurium.