Table 2. Computational promoter analysis.

Operon	First gene	Patten matching
		Fur box-like sequence	Position δ	Sore
hmsT	hmsT	AATGATAATCATAACCAAT	D-272…−254	15.07
		AACAATAATAATTCCCAAC	D-95…−77	8.74
hmsHFRS	hmsH	AATGATGATGAAATGGAAT	R-94…−76	4.58
YPO0450-0448	YPO0450	AATAAGATTTAAGATAAAT	D-139…−121	3.89

A PSSM [13] representing the conserved signals for Fur recognition in Y. pestis was used for the prediction of Fur-box like sequences within the 300 bp upstream DNA regions of the major biofilm-required genetic loci hmsT, hmsHFRS, and YPO0450-0498. The diguanylate cyclase gene YPO0449 was located in the putative operon YPO0450-0498. δ, the minus numbers indicated the nucleotide positions upstream of translation start, and D and R represented the direct and reverse sequences, respectively.