colicin

The colicin operons are generally organized with several major genes.

In short, colicin production may only occur in terminally-ill cells.

A second strain has mutations that eliminate the proteins colicin binds to.

At the same time, colicin is only released from a producing cell by the use of the lysis protein, which results in that cell's death.

The larger plasmids carry other genes as well as the colicin operon.

The colicin itself is repressed by the SOS response and may be regulated in other ways as well.

Its name derives from the fact that it carries a gene for colicin E1 (the cea gene).

A colicin is a type of bacteriocin produced by and toxic to some strains of Escherichia coli.

Such transformations occur in pore forming toxins such as colicin A, alpha-hemolysin, and others.

These include an immunity gene, a colicin structural gene, and a BRP (bacteriocin release protein), or lysis, gene.

Because they target specific receptors and use specific translocation machinery, cells can make themselves resistant to the colicin by repressing or deleting the genes for these proteins.

Mulczyk M, Krukowska A, Slopek S. 1967 Typing of Shigella sonnei by colicin production.

One of them produces a protein, colicin, that's toxic to other cells; it also makes a set of proteins that allow it to survive the toxins it makes.

The immunity gene is often produced constitutively, while the BRP is generally produced only as a read-through of the stop codon on the colicin structural gene.

Mulczyk M, Slopek S, Marcinowska H. 1967 Phage typing, colicin sensitivity and colicinogeny of Shigella flexneri 6.

The molecules secreted vary in size from the small Escherichia coli peptide colicin V, (10 kDa) to the Pseudomonas fluorescens cell adhesion protein LapA of 900 kDa.

The colicin G, H and X determinants encode microcins M and H47, which might utilize the catecholate siderophore receptors FepA, Cir, Fiu and IroN.

Research indicates that retaining the colicin plasmid is very important for cells that live with their relatives, because if a cell loses the immunity gene, it quickly becomes subject to destruction by circulating colicin.

In fact, one of the oldest known so-called colicins was called colicin V and is now known as microcin V. It is much smaller and produced and secreted in a different manner than the classic colicins.

Nucleoside-specific porin (the tsx gene of Escherichia coli) is an outer membrane protein, Tsx, which constitutes the receptor for colicin K and Bacteriophage T6, and functions as a substrate-specific channel for nucleosides and deoxy-nucleosides.

While an undergraduate student, he worked in the laboratory of Dr. Salvador Luria, studying the effects of the bactericidal agent, Colicin K. He received his M.D. degree from the Columbia University College of Physicians and Surgeons in 1976.

In addition, polyamine participate in initiating the expression of SOS response of Colicin E7 operon and down-regulate proteins that are essential for colicin E7 uptake, thus conferring a survival adventage on colicin-producing E. coli under stress conditions.