Abstract
Biofilm plays an important role in pathogenicity of serovar Typhimurium. To understand the molecular mechanism of biofilm formation by Typhimurium, a library of random mutagenized clones was constructed using the commercial Tn5 transposon EZ::TN (TM) < KAN-2 > Tnp Transposome (TM) (Epicentre). This library was screened for phenotypic analyses of their ability to form biofilm and 5 mutants were confirmed to be biofilm deficient. From these mutants, the insertion site flanking sequences were amplified by inverse PCR followed by sequencing. Three mutants had a transposon insertion in gene encoding for flagellar basal body P-ring biosynthesis protein that is required for assembly of the flagellar basal body P-ring. Two mutants had a transposon insertion in the gene encoding for flagellar component of cell-proximal portion of basal-body rod. These mutants were non-motile as confirmed by MSRV and transmission electron microscope suggesting that motility was necessary for biofilm development in Typhimurium.