SASDDJ2: Calcium-bound polcalcin Phl p 7 (polcalcin Phl p 7)

基本情報

• 登録情報: データベース: SASBDB / ID: SASDDJ2

試料

Calcium-bound polcalcin Phl p 7

• polcalcin Phl p 7 (protein), Phleum pratense

• 機能・相同性: EF-hand domain pair / EF-hand, calcium binding motif / EF-Hand 1, calcium-binding site / EF-hand calcium-binding domain. / EF-hand calcium-binding domain profile. / EF-hand domain / EF-hand domain pair / calcium ion binding / Polcalcin Phl p 7
• 生物種: Phleum pratense (オオアワガエリ)
• 引用: ジャーナル: Proteins / 年: 2013; タイトル: Solution structures of polcalcin Phl p 7 in three ligation states: Apo-, hemi-Mg2+-bound, and fully Ca2+-bound.; 著者: Michael T Henzl / Arthur G Sirianni / Wei G Wycoff / Anmin Tan / John J Tanner / ; 要旨: Polcalcins are small EF-hand proteins believed to assist in regulating pollen-tube growth. Phl p 7, from timothy grass (Phleum pratense), crystallizes as a domain-swapped dimer at low pH. This study describes the solution structures of the recombinant protein in buffered saline at pH 6.0, containing either 5.0 mM EDTA, 5.0 mM Mg(2+), or 100 μM Ca(2+). Phl p 7 is monomeric in all three ligation states. In the apo-form, both EF-hand motifs reside in the closed conformation, with roughly antiparallel N- and C-terminal helical segments. In 5.0 mM Mg(2+), the divalent ion is bound by EF-hand 2, perturbing interhelical angles and imposing more regular helical structure. The structure of Ca(2+)-bound Phl p 7 resembles that previously reported for Bet v 4-likewise exposing apolar surface to the solvent. Occluded in the apo- and Mg(2+)-bound forms, this surface presumably provides the docking site for Phl p 7 targets. Unlike Bet v 4, EF-hand 2 in Phl p 7 includes five potential anionic ligands, due to replacement of the consensus serine residue at -x (residue 55 in Phl p 7) with aspartate. In the Phl p 7 crystal structure, D55 functions as a helix cap for helix D. In solution, however, D55 apparently serves as a ligand to the bound Ca(2+). When Mg(2+) resides in site 2, the D55 carboxylate withdraws to a distance consistent with a role as an outer-sphere ligand. (15)N relaxation data, collected at 600 MHz, indicate that backbone mobility is limited in all three ligation states.

登録者

• John Tanner (Mizzou, University of Missouri-Columbia, Columbia, MO, USA)

モデル

• モデル #1715: ; タイプ: atomic / ダミー原子の半径: 1.90 A / カイ2乗値: 3.74441090663; Omokage検索でこの集合体の類似形状データを探す (詳細)

試料

• 試料: 名称: Calcium-bound polcalcin Phl p 7 / 試料濃度: 5.00-15.00
• バッファ: 名称: 0.15M NaCl, 0.025M Hepes, pH 7.4, 100 uM Ca2+ / pH: 7.4

要素 #929

タイプ: protein / 記述: polcalcin Phl p 7 / 分子量: 8.545 / 分子数: 1 / 由来: Phleum pratense / 参照: UniProt: O82040
配列:

ADDMERIFKR FDTNGDGKIS LSELTDALRT LGSTSADEVQ RMMAEIDTDG DGFIDFNEFI SFCNANPGLM KDVAKVF

実験情報

• ビーム: 設備名称: Advanced Light Source (ALS) 12.3.1 (SIBYLS) / 地域: Berkeley, CA / 国: USA / 線源: X-ray synchrotronシンクロトロン / 波長: 0.1127 Å
• 検出器: 名称: MAR 165 CCD

スキャン

タイトル: Calcium-bound Phl p 7 / 測定日: 2011年12月8日 / セル温度: 10 °C / 単位: 1/A /

	Min	Max
Q	0.021	0.3256

距離分布関数 P(R)

ソフトウェア P(R): GNOM 5.0 / ポイント数: 502 /

	Min	Max
Q	0.020978	0.325586
P(R) point	1	502
R	0	36.19

結果

カーブのタイプ: single_conc /

	実験値	Porod
分子量	8.545 kDa	8.5 kDa
体積	-	13.6 nm3

	P(R)	Guinier	Guinier error
前方散乱 I0	52.19	52.54	0.075
慣性半径, Rg	1.27 nm	1.29 nm	0.003

	Min	Max
D	-	3.62
Guinier point	1	132