Recent study by Dr. Shakibaie M.R and co-workers revealed that at low iron concenteration the expression of biofilm associated protein (bap ) gene increases four fold

The sequence of bap was determined and deposited in the GenBank database (accession no. KR080550.1). Expression of bap in the presence of low iron was analyzed by relative quantitative real time PCR (rqRT­PCR). Nearly half of the isolates belonged to RAPD­types A and B remaining were either small clusters or singleton. The results of biofilm formation revealed that 23 (35.4%), 18 (27.7%), 13 (20%), and 11 (16.9%) of the isolates had strong, moderate, weak, and no biofilm activities, respectively. ompA and csuE genes were detected in all, while bap and bla were detected in 43 (66%) and 42 (64%) of the isolates that showed strong and moderate biofilm activities (p ≤ 0.05), respectively. Analysis of bap expression by rqRT­PCR revealed five isolates with four­fold bap overexpression in the presence of low iron concentration (20 µM).