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1e68
From Proteopedia
SOLUTION STRUCTURE OF BACTERIOCIN AS-48
Overview
The solution structure of bacteriocin AS-48, a 70-residue cyclic polypeptide from Enterococcus faecalis, consists of a globular arrangement of five alpha-helices enclosing a compact hydrophobic core. The head-to-tail union lies in the middle of helix 5, a fact that is shown to have a pronounced effect on the stability of the three-dimensional structure. Positive charges in the side chains of residues in helix 4 and in the turn linking helix 4 to helix 5 form a cluster that most probably determine its antibacterial activity by promoting pore formation in cell membranes. A similar five-helix structural motif has been found in the antimicrobial NK-lysin, an effector polypeptide of T and natural killer (NK) cells. Bacteriocin AS-48 lacks the three disulfide bridges characteristic of the saposin fold present in NK-lysin, and has no sequence homology with it. Nevertheless, the similar molecular architecture and high positive charge strongly suggest a common mechanism of antibacterial action.
About this Structure
1E68 is a Single protein structure of sequence from Enterococcus faecalis. Full crystallographic information is available from OCA.
Reference
Bacteriocin AS-48, a microbial cyclic polypeptide structurally and functionally related to mammalian NK-lysin., Gonzalez C, Langdon GM, Bruix M, Galvez A, Valdivia E, Maqueda M, Rico M, Proc Natl Acad Sci U S A. 2000 Oct 10;97(21):11221-6. PMID:11005847 Page seeded by OCA on Fri May 2 14:42:53 2008
