Abstract: Methods are provided for identifying molecules that can be used to positively and negatively manipulate quorum-sensing-mediated communication to control bacterial behavior. Small-molecule antagonists that disrupt quorum-sensing-mediated activities are identified. Methods are provided for disrupting detection of acyl-homoserine lactone autoinducer in Gram-negative bacteria by contacting the bacteria with the antagonists. Methods of inhibiting quorum sensing-mediated activity in Gram-negative bacteria are provided wherein the activity is pathogenicity, bioluminescence, siderophore production, type III secretion, or metalloprotease production.

Abstract: Methods are provided for identifying molecules that can be used to positively and negatively manipulate quorum-sensing-mediated communication to control bacterial behavior. Small-molecule antagonists that disrupt quorum-sensing-mediated activities are identified. Methods are provided for disrupting detection of acyl-homoserine lactone autoinducer in Gram-negative bacteria by contacting the bacteria with the antagonists. Methods of inhibiting quorum sensing-mediated activity in Gram-negative bacteria are provided wherein the activity is pathogenicity, bioluminescence, siderophore production, type III secretion, or metalloprotease production.

Abstract: Methods are provided for identifying molecules that can be used to positively and negatively manipulate quorum-sensing-mediated communication to control bacterial behavior. Small-molecule antagonists that disrupt quorum-sensing-mediated activities are identified. Methods are provided for disrupting detection of acyl-homoserine lactone autoinducer in Gram-negative bacteria by contacting the bacteria with the antagonists. Methods of inhibiting quorum sensing-mediated activity in Gram-negative bacteria are provided wherein the activity is pathogenicity, bioluminescence, siderophore production, type III secretion, or metalloprotease production.

Abstract: Methods are provided for identifying molecules that can be used to positively and negatively manipulate quorum-sensing-mediated communication to control bacterial behavior. Small-molecule antagonists that disrupt quorum-sensing-mediated activities are identified. Methods are provided for disrupting detection of acyl-homoserine lactone autoinducer in Gram-negative bacteria by contacting the bacteria with the antagonists. Methods of inhibiting quorum sensing-mediated activity in Gram-negative bacteria are provided wherein the activity is pathogenicity, bioluminescence, siderophore production, type III secretion, or metalloprotease production.

Abstract: Methods are provided for identifying molecules that can be used to positively and negatively manipulate quorum-sensing-mediated communication to control bacterial behavior. Small-molecule antagonists that disrupt quorum-sensing-mediated activities are identified. Methods are provided for disrupting detection of acyl-homoserine lactone autoinducer in Gram-negative bacteria by contacting the bacteria with the antagonists. Methods of inhibiting quorum sensing-mediated activity in Gram-negative bacteria are provided wherein the activity is pathogenicity, bioluminescence, siderophore production, type III secretion, or metalloprotease production.

Abstract: A bacterial autoinducer, CAI-1, was purified and its structure identified. Methods for synthesis of the autoinducer and its analogues were elucidated. Methods of using the autoinducer or its analogues for treating bacterial pathogenicity and bio film formation are described. Methods for prevention and treatment of cholera are described. Synthetic (S)-3-hydroxytridecan-4-one functions as well as natural CAI-1 in repressing production of the virulence factor toxin co-regulated pilus (TCP). Strategies are described to manipulate bacterial quorum sensing in the clinical arena.

Abstract: Methods are provided for identifying molecules that can be used to positively and negatively manipulate quorum-sensing-mediated communication to control bacterial behavior. Small-molecule antagonists that disrupt quorum-sensing-mediated activities are identified. Methods are provided for disrupting detection of acyl-homoserine lactone autoinducer in Gram-negative bacteria by contacting the bacteria with the antagonists. Methods of inhibiting quorum sensing-mediated activity in Gram-negative bacteria are provided wherein the activity is pathogenicity, bioluminescence, siderophore production, type III secretion, or metalloprotease production.

Abstract: A crystal comprising LuxP is obtained, and a binding site for autoinducer-2 (AI-2) identified. The X-ray crystallographic data for LuxP and a LuxP-AI-2 complex is determined and used in a drug discovery method. Pharmaceutical compositions comprising ligands identified by such drug discovery methods are used to treat bacterial infections.

Abstract: The invention relates to the identification and isolation of a novel sigma 54 (?54) transcription factor from Vibrio harveyi. The invention further relates to the identification of ?54 interactions with LuxO. More particularly, the invention provides methods for identifying compounds that regulate bacterial cell growth and virulence by regulating LuxO-?54 activities.

Abstract: The present invention relates to the discovery of the lsr operon, the genes therein, and the polypeptides encoded by these genes. The present invention also includes strains with altered expression levels of the polypeptides encoded by the genes and the lsr operon relative to wild type cells. In some embodiments, the strains express a transporter that transports an autoinducer into the cell at a level higher than that of wild type cells. The present invention also includes methods for identifying compounds that modulate the transport of the autoinducer into cells.

Abstract: This invention relates to crystals comprising apo-LsrB and holo-LsrB. The structure of holo-LsrB identifies a tetrahydroxytetrahydrofuran derived from 4,5-dihydroxy-2,3-pentanedione (DPD) as the active autoinducer-2 (AI-2) molecule in Salmonella typhimurium. The X-ray crystallographic data can be used in a drug discovery method. Additionally the invention provides AI-2 analogs based on this discovery as well as pharmaceutical compositions containing those analogs.

Abstract: This invention relates to crystals comprising apo-LsrB and holo-LsrB. The structure of holo-LsrB identifies a tetrahydroxytetrahydrofuran derived from 4,5-dihydroxy-2,3-pentanedione (DPD) as the active autoinducer-2 (AI-2) molecule in Salmonella typhimurium. The X-ray crystallographic data can be used in a drug discovery method. Additionally the invention provides AI-2 analogs based on this discovery as well as pharmaceutical compositions containing those analogs.

Abstract: Quorum-sensing bacteria communicate with extracellular signal molecules called autoinducers to allow community-wide synchronization of gene expression. The present invention relates to the identification the Vibrio harveyi and Vibrio cholerae protein Hfq as mediating interactions between small, regulatory RNAs (sRNAs) and specific messenger RNA (mRNA) targets. Accordingly, the present invention provides nucleic acids encoding the Vibrio sRNAs, strains having various deletions and mutations of one or more qrr genes encoding these sRNA as well as methods of identifying quorum-sensing regulators. Additionally, the invention relates to an isolated V. harveyi Hfq protein and conservative amino acid substitutions thereof as well as nucleic acids encoding those proteins, recombinant methods of producing those proteins and antibodies against those proteins.

Abstract: Three genes involved in the catabolism of chitin in Vibrio furnissii: endI encodes periplasmic chitodextrinase, exoI encodes periplasmic .beta.-N-acetylglucosaminidase, and exoII encodes aryl .beta.-N-acetylglucosaminidase are provided. The complete nucleotide sequence for each of the three genes and the complete amino acid for the corresponding enzymes are demonstrated along with host cells capable of expressing the recombinant enzymes. The present invention also describes four specific strains of V. furnissii having deletions in genes involved in the catabolic pathway of chitin and a process for the production of chitin oligosaccharides.

Abstract: The present invention reveals the cloning of four genes involved in the catabolism of chitin in Vibrio furnissii: endI encodes periplasmic chitodextrinase, exoI encodes periplasmic .beta.-N-acetylglucosaminidase, exoII encodes aryl .beta.-N-acetyl-glucosaminidase and chiA encodes extracellular chitinase. The complete nucleotide sequence for each of the four genes and the complete amino acid for the corresponding enzymes are demonstrated along with host cells capable of expressing the recombinant enzymes. The present invention also describes four specific strains of V. furnissii having deletions in genes involved in the catabolic pathway of chitin and a process for the production of chitin oligosaccharides.