Agr is an autoinducing, quorum-sensing system that functions in many Gram-positive species and is best characterized in the pathogen Staphylococcus aureus, in which it is a global regulator of virulence gene expression. Allelic variations in the agr genes have resulted in the emergence of four quorum-sensing specificity groups in S. aureus, which correlate with different strain pathotypes. The ...

Classical quorum-sensing (autoinduction) regulation, as exemplified by the lux system of Vibrio fischeri, requires N-acyl homoserine lactone (AHL) signals to stimulate cognate transcriptional activators for the cell density-dependent expression of specific target gene systems. For Pantoea stewartii subsp. stewartii, a bacterial pathogen of sweet corn and maize, the extracellular polysaccharide ...

Distributed software transactional memory (D-STM) promises to alleviate difficulties with lock-based (distributed) synchronization and object performance bottlenecks in distributed systems. Past single copy data-flow (SC) D-STM proposals keeps only one writable copy of each object in the system and are not fault-tolerant in the presence of network node/link failures in large-scale distributed s...

Brucella quorum sensing has been described as an important regulatory system controlling crucial virulence determinants such as the VirB type IV secretion system and the flagellar genes. However, the basis of quorum sensing, namely the production of autoinducers in Brucella has been questioned. Here, we report data obtained from the use of a genetic tool allowing the in situ detection of long-c...

A failure detection service is perfect if it eventually detects all failures and every detection correctly identifies a failure that has already occurred. Such a perfect failure detection service serves as a basic building block for many reliable distributed systems, for example in primary/backup replication protocols and distributed lock services. In this paper, we present a comprehensive stud...

quorum sensing controls the luminescence of vibrio fischeri through the transcriptional activator luxr and the specific autoinducer signal produced by luxi. amino acid sequences of these two genes were analyzed using bioinformatics tools. luxi consists of 193 amino acids and appears to contain five α-helices and six ß-sheets when analyzed by sspro8. luxi belongs to the autoinducer synthetase fa...

Quorum sensing allows bacteria to sense and respond to changes in population density. Acyl-homoserine lactones serve as quorum-sensing signals for many Proteobacteria, and acyl-homoserine lactone signaling is known to control cooperative activities. Quorum-controlled activities vary from one species to another. Quorum-sensing controls a constellation of genes in the opportunistic pathogen Pseud...

Quorum sensing is a regulatory system for controlling gene expression in response to increasing cell density. N-Acylhomoserine lactone (AHL) is produced by gram-negative bacteria, which use it as a quorum-sensing signal molecule. Serratia marcescens is a gram-negative opportunistic pathogen which is responsible for an increasing number of serious nosocomial infections. S. marcescens AS-1 produc...

We develop mathematical models to examine the formation, growth and quorum sensing activity of bacterial biofilms. The growth aspects of the model are based on the assumption of a continuum of bacterial cells whose growth generates movement, within the developing biofilm, described by a velocity field. A model proposed in Ward et al. (2001) to describe quorum sensing, a process by which bacteri...

An ideal gene drive system to alter wild populations would 1) exclusively affect organisms within the political boundaries of consenting communities, and 2) be capable of restoring any engineered population to its original genetic state. Here we describe 'daisy quorum' drive systems that meet these criteria by combining daisy drive with underdominance. A daisy quorum drive system is predicted t...