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.