1F55

SOLUTION STRUCTURE OF THE CALCIUM BOUND N-TERMINAL DOMAIN OF YEAST CALMODULIN

1F55 の概要

• エントリーDOI: 10.2210/pdb1f55/pdb
• 関連するPDBエントリー: 1F54
• 分子名称: CALMODULIN, CALCIUM ION (2 entities in total)
• 機能のキーワード: ef-hand, helix-loop-helix, transport protein
• 由来する生物種: Saccharomyces cerevisiae (baker's yeast)
• 細胞内の位置: Cytoplasm, cytoskeleton, spindle pole body: P06787
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 8626.52

構造登録者

Ishida, H.,Takahashi, K.,Nakashima, K.,Kumaki, Y.,Nakata, M.,Hikichi, K.,Yazawa, M. (登録日: 2000-06-13, 公開日: 2003-07-15, 最終更新日: 2024-05-22)

主引用文献

Ishida, H.,Takahashi, K.,Nakashima, K.,Kumaki, Y.,Nakata, M.,Hikichi, K.,Yazawa, M.
Solution Structures of the N-terminal Domain of Yeast Calmodulin: Ca2+-Dependent Conformational Change and Its Functional Implication
Biochemistry, 39:13660-13668, 2000

PubMed Abstract: We have determined solution structures of the N-terminal half domain (N-domain) of yeast calmodulin (YCM0-N, residues 1-77) in the apo and Ca(2+)-saturated forms by NMR spectroscopy. The Ca(2+)-binding sites of YCM0-N consist of a pair of helix-loop-helix motifs (EF-hands), in which the loops are linked by a short beta-sheet. The binding of two Ca(2+) causes large rearrangement of the four alpha-helices and exposes the hydrophobic surface as observed for vertebrate calmodulin (CaM). Within the observed overall conformational similarity in the peptide backbone, several significant conformational differences were observed between the two proteins, which originated from the 38% disagreement in amino acid sequences. The beta-sheet in apo YCM0-N is strongly twisted compared with that in the N-domain of CaM, while it turns to the normal more stable conformation on Ca(2+) binding. YCM0-N shows higher cooperativity in Ca(2+) binding than the N-domain of CaM, and the observed conformational change of the beta-sheet is a possible cause of the highly cooperative Ca(2+) binding. The hydrophobic surface on Ca(2+)-saturated YCM0-N appears less flexible due to the replacements of Met51, Met71, and Val55 in the hydrophobic surface of CaM with Leu51, Leu71, and Ile55, which is thought to be one of reasons for the poor activation of target enzymes by yeast CaM.

PubMed: 11076504
DOI: 10.1021/bi000582x

実験手法

SOLUTION NMR