Background: N-Acyl homoserine lactone (AHL) is found to be the main component of quorum sensing (QS) in Gram-negative bacteria and plays an important role in biofilm formation. Little information is available regarding the role of AHL in biofilm formation in Escherichia coli (E. coli). The purpose of this investigation was to biochemically detect and characterize AHL activity in biofilm-forming...

problem of evil is something which is considered against existence of god or his attributes like being omnipotent and absolutely good. philosophers and theologians have tried to solve this problem by different ways. the solution which is accepted by muslim philosophers is the nothingness of evils. according to this opinion evils are not except nothing of essence or perfections of essence. in th...

An investigation of name-bearing types and other relevant type specimens of twelve nominal Leptopelis taxa described from or distributed in the Eastern Arc Mountains in East Africa was carried out. Our aim was to clarify their status and where necessary revise respective nomina. We suggest several nomenclatural and taxonomic actions: 1) Leptopelis barbouri Ahl, 1929 is transferred to the synony...

Algebraic High-Level (AHL) nets are a well-known modelling technique based on Petri nets with algebraic data types, which allows to model the communication structure and the data flow within one modelling framework. Transformations of AHL-nets – inspired by the theory of graph transformations – allow in addition to modify the communication structure. Moreover, high-level processes of AHL-nets c...

Many Proteobacteria govern responses to changes in cell density by using acyl-homoserine lactone (AHL) quorum-sensing (QS) signaling. Similar to the LuxI-LuxR system described in Vibrio fischeri, a minimal AHL QS circuit comprises a pair of genes, a luxI-type synthase gene encoding an enzyme that synthesizes an AHL and a luxR-type AHL-responsive transcription regulator gene. In most bacteria th...

N-acylhomoserine lactone (AHL)-based quorum sensing (QS) is important for the regulation of proteobacterial virulence determinants. Thus, the inhibition of AHL synthases offers non-antibiotics-based therapeutic potentials against QS-mediated bacterial infections. In this work, functional AHL synthases of Pseudomonas aeruginosa LasI and RhlI were heterologously expressed in an AHL-negative Esche...

Ulva zoospores preferentially settle on N-acylhomoserine lactone (AHL) producing marine bacterial biofilms. To investigate whether AHL signal molecules also affect the success and rate of zoospore germination in addition to zoospore attraction, the epiphytic bacteria associated with mature Ulva linza were characterized and bacterial isolates representative of this community tested for the abili...