2K19

NMR solution structure of PisI

2K19 の概要

• エントリーDOI: 10.2210/pdb2k19/pdb
• NMR情報: BMRB: 15673
• 分子名称: Putative piscicolin 126 immunity protein (1 entity in total)
• 機能のキーワード: pisi, immunity protein, bacteriocin, immune system, antimicrobial protein
• 由来する生物種: Carnobacterium maltaromaticum
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 11197.76

構造登録者

Martin-Visscher, L.A.,Sprules, T.,Gursky, L.J.,Vederas, J.C. (登録日: 2008-02-25, 公開日: 2008-06-17, 最終更新日: 2024-05-08)

主引用文献

Martin-Visscher, L.A.,Sprules, T.,Gursky, L.J.,Vederas, J.C.
Nuclear magnetic resonance solution structure of PisI, a group B immunity protein that provides protection against the type IIa bacteriocin piscicolin 126, PisA.
Biochemistry, 47:6427-6436, 2008

PubMed Abstract: Lactic acid bacteria produce and secrete bacteriocins. These bacteriocins are potent antimicrobial peptides that are active against other closely related bacteria. As a means of self-protection, producer organisms also express immunity proteins. Immunity proteins are generally located on the same genetic locus and are cotranscribed with the bacteriocin. Although some cross immunity between bacteriocins has been observed, immunity proteins are typically highly specific. Immunity proteins for the type IIa bacteriocins range from 81 to 115 amino acids in length and display substantial variation in their sequences. Nonetheless, such immunity proteins have been classified into three groupings (groups A, B, and C) according to sequence homology. The structures of a group C (ImB2) and two group A (EntA-im and PedB) immunity proteins have previously been reported. We herein report the nuclear magnetic resonance solution structure of the remaining class of the type IIa immunity proteins. PisI, a 98-amino acid protein, is a group B immunity protein conferring immunity against piscicolin 126 (PisA). Like ImB2, EntA-im, and PedB, PisI folds into a globular protein in aqueous solution and contains an antiparallel four-helix bundle. Compared to ImB2 and EntA-im, PisI has a substantially longer and more flexible N-terminus, but a shorter C-terminus. No direct interaction between the bacteriocin and immunity protein is observed by NMR in either aqueous or membrane mimicking environments. This further suggests that the mechanism that mediates immunity is not due to a direct bacteriocin-immunity protein interaction but rather is receptor-mediated. It has now been confirmed that the four-helix bundle is indeed a structural motif among the type IIa immunity proteins.

PubMed: 18500825
DOI: 10.1021/bi8004076

実験手法

SOLUTION NMR