Antimicrobial Pressure of Ciprofl oxacin and Gentamicin on Biofi lm Development by an Endoscope-Isolated Pseudomonas aeruginosa

Abstract

Background: Yersinia pestis synthesizes the attached biofilms in the flea proventriculus, which is important for the transmission of this pathogen by fleas. The hmsHFRS operons is responsible for the synthesis of exopolysaccharide (the major component of biofilm matrix), which is activated by the signaling molecule 39, 59-cyclic diguanylic acid (c-di-GMP) synthesized by the only two diguanylate cyclases HmsT, and YPO0449 (located in a putative operonYPO0450-0448).

CRP Is an Activator of Yersinia pestis Biofilm Formation that Operates via a Mechanism Involving gmhA and waaAE-coaD

“…As described in our previous studies ( Sun et al, 2012 ; Zhang et al, 2013a , b ) a 5′- 32 P-labeled oligonucleotide primer complementary to a portion of the RNA transcript of each indicated gene was employed to synthesize cDNAs from total RNA templates using the Promega Primer Extension System. If different Y. pestis strains were involved in a single experiment, equal amounts of total RNA were used as starting materials.…”

“…A promoter-proximal DNA region of each indicated gene was cloned into the low-copy-number transcriptional fusion vector pRW50 ( Lodge et al, 1992 ) that harbors a promoterless lacZ reporter gene. Y. pestis strains transformed with the recombinant plasmid or the empty pRW50 (negative control) were cultivated to measure β-galactosidase activity in the cellular extract using the β-galactosidase Enzyme Assay System (Promega) ( Sun et al, 2012 ; Zhang et al, 2013a , b ).…”

“…For EMSA ( Sun et al, 2012 ; Zhang et al, 2013a ), promoter-proximal DNA regions were prepared by PCR amplification. EMSA was performed using the Gel Shift Assay Systems (Promega).…”