The chemolithoautotrophic bacterium Nitrosospira multiformis is involved in affecting the process of nitrogen cycling. Here we report the existence and characterization of a functional quorum sensing signal synthase in N. multiformis. One gene (nmuI) playing a role in generating a protein with high levels of similarity to N-acyl homoserine lactone (AHL) synthase protein families was identified....

Many pathogenic bacteria use quorum sensing (QS) systems to regulate the expression of virulence genes in a density-dependent manner. In one widespread QS paradigm the enzyme LuxI generates a small diffusible molecule of the acyl-homoserine lactone (AHL) family; high cell densities lead to high AHL levels; AHL binds the transcription factor LuxR, triggering it to activate gene expression at a v...

among factors causing disagreement of shiites and sunnis is commentatorial   hadiths. such hadiths are of great significance in the process of understanding as well as commenting on the quran–and even inferring juristic precepts. hence, attitude of muslims towards such   hadiths play a significant role in the process of formation of their beliefs and inferring islamic precepts. attitude of sunn...

In Gram-negative bacteria, quorum sensing is mediated by N-acylhomoserine lactones (AHL) to regulate different biological functions, including production of virulence factors. Quorum quenching refers to the interruption of quorum sensing, and the most attractive way is to degrade the AHL molecules. With the aim of isolating soil bacteria capable of blocking quorum sensing by inactivating AHL, a...

BACKGROUND Aeromonas hydrophila is a serious pathogen and can cause hemorrhagic septicemia in fish. To control this disease, antibiotics and chemicals are widely used which can consequently result in "superbugs" and chemical accumulation in the food chain. Though vaccine against A. hydrophila is available, its use is limited due to multiple serotypes of this pathogen and problems of safety and ...

Citrobacter freundii strain ST2, isolated from the algae bloom sample, possesses an N-acylhomoserine lactone (AHL) production activity that secretes short-chain AHL molecules. In this study, we sequenced the complete genome of C. freundii strain ST2 to understand the molecular regulation of the AHL system and to search for the AHL gene in this bacterium. The results show that the genome size is...