A Class IV Adenylate Cyclase, CyaB, Is Required for Capsule Polysaccharide Production and Biofilm Formation in Vibrio parahaemolyticus.

Cyclic AMP (cAMP) receptor protein (CRP), encoded by , is a global regulator that is activated by cAMP, a second messenger synthesized by a class I adenylate cyclase (AC-I) encoded by in Escherichia coli. cAMP-CRP is required for growth on nonpreferred carbon sources and is a global regulator. We constructed in-frame nonpolar deletions of the and homologs in Vibrio parahaemolyticus and found that the Δ mutant did not grow in minimal media supplemented with nonpreferred carbon sources, but the Δ mutant grew similarly to the wild type.

Fis Connects Two Sensory Pathways, Quorum Sensing and Surface Sensing, to Control Motility in .

Factor for inversion stimulation (Fis) is a global regulator that is highly expressed during exponential phase growth and undetectable in stationary phase growth. Quorum sensing (QS) is a global regulatory mechanism that controls gene expression in response to changes in cell density and growth phase. In , a marine species and a significant human pathogen, the QS regulatory sRNAs, Qrr1 to Qrr5, are expressed during exponential growth and negatively regulate the high cell density QS master regulator OpaR.

Regulatory Small RNA Qrr2 Is Expressed Independently of Sigma Factor-54 and Can Function as the Sole Qrr Small RNA To Control Quorum Sensing in Vibrio parahaemolyticus.

Bacterial cells alter gene expression in response to changes in population density in a process called quorum sensing (QS). In Vibrio harveyi, LuxO, a low-cell-density activator of sigma factor-54 (RpoN), is required for transcription of five noncoding regulatory small RNAs (sRNAs), Qrr1 to Qrr5, which each repress translation of the master QS regulator, LuxR. Vibrio parahaemolyticus, the leading cause of bacterial seafoodborne gastroenteritis, also contains five Qrr sRNAs that control OpaR (the LuxR homolog), controlling capsule polysaccharide (CPS), motility, and metabolism.

Object classification and acoustic imaging with active sonar.

The theoretical underpinnings of underwater acoustic classification and imaging using high-frequency active sonar are studied. All essential components of practical classification systems are incorporated in a Bayesian theoretic framework. The optimum decision rules and array processing are presented and evaluated.