1TDP

NMR solution structure of the carnobacteriocin B2 immunity protein

1TDP の概要

• エントリーDOI: 10.2210/pdb1tdp/pdb
• NMR情報: BMRB: 6211
• 分子名称: carnobacteriocin B2 immunity protein (1 entity in total)
• 機能のキーワード: four-helix bundle, 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: 12680.63

構造登録者

Sprules, T.,Kawulka, K.E.,Vederas, J.C. (登録日: 2004-05-23, 公開日: 2004-09-28, 最終更新日: 2024-05-22)

主引用文献

Sprules, T.,Kawulka, K.E.,Vederas, J.C.
NMR Solution Structure of ImB2, a Protein Conferring Immunity to Antimicrobial Activity of the Type IIa Bacteriocin, Carnobacteriocin B2
Biochemistry, 43:11740-11749, 2004

PubMed Abstract: Bacteriocins produced by lactic acid bacteria are potent antimicrobial compounds which are active against closely related bacteria. Producer strains are protected against the effects of their cognate bacteriocins by immunity proteins that are located on the same genetic locus and are coexpressed with the gene encoding the bacteriocin. Several structures are available for class IIa bacteriocins; however, to date, no structures are available for the corresponding immunity proteins. We report here the NMR solution structure of the 111-amino acid immunity protein for carnobacteriocin B2 (ImB2). ImB2 folds into a globular domain in aqueous solution which contains an antiparallel four-helix bundle. Extensive packing by hydrophobic side chains in adjacent helices forms the core of the protein. The C-terminus, containing a fifth helix and an extended strand, is held against the four-helix bundle by hydrophobic interactions with helices 3 and 4. Most of the charged and polar residues in the protein face the solvent. Helix 3 is well-defined to residue 55, and a stretch of nascent helix followed by an unstructured loop joins it to helix 4. No interaction is observed between ImB2 and either carnobacteriocin B2 (CbnB2) or its precursor. Protection from the action of CbnB2 is only observed when ImB2 is expressed within the cell. The loop between helices 3 and 4, and a hydrophobic pocket which it partially masks, may be important for interaction with membrane receptors responsible for sensitivity to class IIa bacteriocins.

PubMed: 15362858
DOI: 10.1021/bi048854+

実験手法

SOLUTION NMR