3BOI

Snow Flea Antifreeze Protein Racemate

3BOI の概要

• エントリーDOI: 10.2210/pdb3boi/pdb
• 関連するPDBエントリー: 2PNE 3B0G
• 分子名称: 6.5 kDa glycine-rich antifreeze protein (2 entities in total)
• 機能のキーワード: racemate, sfafp, mirror image proteins, racemic protein crystallography, antifreeze protein
• 由来する生物種: Hypogastrura harveyi
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 12979.62

構造登録者

Pentelute, B.L.,Kent, S.B.H.,Gates, Z.P.,Tereshko, V.,Kossiakoff, A.A.,Kurutz, J.,Dashnau, J.,Vaderkooi, J.M. (登録日: 2007-12-17, 公開日: 2008-09-23, 最終更新日: 2024-11-13)

主引用文献

Pentelute, B.L.,Gates, Z.P.,Tereshko, V.,Dashnau, J.L.,Vanderkooi, J.M.,Kossiakoff, A.A.,Kent, S.B.
X-ray structure of snow flea antifreeze protein determined by racemic crystallization of synthetic protein enantiomers
J.Am.Chem.Soc., 130:9695-9701, 2008

PubMed Abstract: Chemical protein synthesis and racemic protein crystallization were used to determine the X-ray structure of the snow flea antifreeze protein (sfAFP). Crystal formation from a racemic solution containing equal amounts of the chemically synthesized proteins d-sfAFP and l-sfAFP occurred much more readily than for l-sfAFP alone. More facile crystal formation also occurred from a quasi-racemic mixture of d-sfAFP and l-Se-sfAFP, a chemical protein analogue that contains an additional -SeCH2- moiety at one residue and thus differs slightly from the true enantiomer. Multiple wavelength anomalous dispersion (MAD) phasing from quasi-racemate crystals was then used to determine the X-ray structure of the sfAFP protein molecule. The resulting model was used to solve by molecular replacement the X-ray structure of l-sfAFP to a resolution of 0.98 A. The l-sfAFP molecule is made up of six antiparallel left-handed PPII helixes, stacked in two sets of three, to form a compact brick-like structure with one hydrophilic face and one hydrophobic face. This is a novel experimental protein structure and closely resembles a structural model proposed for sfAFP. These results illustrate the utility of total chemical synthesis combined with racemic crystallization and X-ray crystallography for determining the unknown structure of a protein.

PubMed: 18598029
DOI: 10.1021/ja8013538

実験手法

X-RAY DIFFRACTION (1 Å)