9.B.13 The Putative Pore-forming Entericidin (ECN) Family

&9;The ECN family includes two small lipoproteins, Entericidin B (a bacteriolytic toxin; 27 amino acyl residues) and Entericidin A (an anti-toxin antibiotic; 23 residues) in which the amino terminal cysteine is derivatized with an N-acyl-S-sn-1,2 diacyl glyceryl moiety. Both lipoproteins are predicted to adopt amphipathic α-helical structures in phospholipid bilayers and to thereby modulate membrane stability. These two small lipoproteins are tandemly encoded in the ecn locus of the E. coli chromosome; their syntheses are induced in stationary phase, and they mediate programmed cell death of a subpopulation of the bacteria. It is possible that Entericidin B exerts its toxic effect by forming transmembrane pores, but this possibility has not been established.



This family belongs to the .

 

References:

Bishop, R.E., S.S. Penfold, L.S. Frost, J.V. Holtje, J.H. Weiner (1995). Stationary phase expression of a novel Escherichia coli outer membrane lipoprotein and its relationship with mammalian Apolipoprotein D - implications for the origin of lipocalins. J. Biol. Chem. 270:23097-23103.

Bishop, R.E., B.K. Leskiw, R.S. Hodges, C.M. Kay and J.H. Weiner (1998). The entericidin locus of Escherichia coli and its implications for programmed bacterial cell death. J. Mol. Biol. 280: 583-596.

Examples:

TC#NameOrganismal TypeExample
9.B.13.1.1Putative pore-forming lipoprotein toxin EcnB

γ-Proteobacteria

Entericidin B (EcnB) of E. coli (P0ADB7)
 
9.B.13.1.2

Enterocidin B, EcnB

γ-Proteobacteria

EcnB of Halomonas sp. GFAJ-1

 
Examples:

TC#NameOrganismal TypeExample
9.B.13.2.1

Enterocidin B, EcnB

α-Proteobacteria

EcnB of Caulobacter crescentus

 
9.B.13.2.2

Enterocidin B, EcnB

α-Proteobacteria

EcnB of Caenispirllum salinarum