Periplasmic mar operon regulator; Multiple antibiotic resistance protein; Protein involved in response to drug and xenobiotic metabolic process.

Ara regulon transcriptional activator; Transcription factor that regulates the expression of several genes involved in the transport and metabolism of L-arabinose. Functions both as a positive and a negative regulator. In the presence of arabinose, activates the expression of the araBAD, araE, araFGH and araJ promoters. In the absence of arabinose, negatively regulates the araBAD operon. Represses its own transcription. Acts by binding directly to DNA.

Transcriptional repressor; Potential regulator protein for the acrAB genes.

Transport channel; Outer membrane channel, which is required for the function of several efflux systems such as AcrAB-TolC, AcrEF-TolC, EmrAB-TolC and MacAB-TolC. These systems are involved in export of antibiotics and other toxic compounds from the cell. TolC is also involved in import of colicin E1 into the cells.

Multidrug efflux system; AcrA-AcrB-AcrZ-TolC is a drug efflux protein complex with broad substrate specificity that uses the proton motive force to export substrates. This subunit may act as an adapter protein that links AcrB and TolC stably together. It is elongated in shape, being long enough to span the periplasm.

30S ribosomal subunit protein S4; One of two assembly initiator proteins for the 30S subunit, it binds directly to 16S rRNA where it nucleates assembly of the body of the 30S subunit. Plays a role in mRNA unwinding by the ribosome, possibly by forming part of a processivity clamp. Also functions as a rho-dependent antiterminator of rRNA transcription, increasing the synthesis of rRNA under conditions of excess protein, allowing a more rapid return to homeostasis. Binds directly to RNA polymerase; Belongs to the universal ribosomal protein uS4 family.

Outer membrane porin 1a (Ia;b;F); Forms pores that allow passive diffusion of small molecules across the outer membrane. (Microbial infection) A mixed OmpC-OmpF heterotrimer is the outer membrane receptor for toxin CdiA-EC536; polymorphisms in extracellular loops 4 and 5 of OmpC confer susceptibility to CdiA- EC536-mediated toxicity; Belongs to the Gram-negative porin family.

Redox-sensitive transcriptional activator of soxS; Activates the transcription of the soxS gene which itself controls the superoxide response regulon. SoxR contains a 2Fe-2S iron- sulfur cluster that may act as a redox sensor system that recognizes superoxide. The variable redox state of the Fe-S cluster is employed in vivo to modulate the transcriptional activity of SoxR in response to specific types of oxidative stress. Upon reduction of 2Fe-2S cluster, SoxR reversibly loses its transcriptional activity, but retains its DNA binding affinity.

DNA gyrase (type II topoisomerase), subunit A; A type II topoisomerase that negatively supercoils closed circular double-stranded (ds) DNA in an ATP-dependent manner to maintain chromosomes in an underwound state. This makes better substrates for topoisomerase IV (ParC and ParE) which is the main enzyme that unlinks newly replicated chromosomes in E.coli. Gyrase catalyzes the interconversion of other topological isomers of dsDNA rings, including catenanes. Relaxes negatively supercoiled DNA in an ATP-independent manner. E.coli gyrase has higher supercoiling activity than many other bac [...]