3MBA

APLYSIA LIMACINA MYOGLOBIN. CRYSTALLOGRAPHIC ANALYSIS AT 1.6 ANGSTROMS RESOLUTION

3MBA の概要

• エントリーDOI: 10.2210/pdb3mba/pdb
• 分子名称: MYOGLOBIN, FLUORIDE ION, PROTOPORPHYRIN IX CONTAINING FE, ... (4 entities in total)
• 機能のキーワード: oxygen storage
• 由来する生物種: Aplysia limacina (slug sea hare)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 15984.92

構造登録者

Bolognesi, M.,Onesti, S.,Gatti, G.,Coda, A.,Ascenzi, P.,Brunori, M. (登録日: 1989-02-22, 公開日: 1990-01-15, 最終更新日: 2024-10-23)

主引用文献

Bolognesi, M.,Onesti, S.,Gatti, G.,Coda, A.,Ascenzi, P.,Brunori, M.
Aplysia limacina myoglobin. Crystallographic analysis at 1.6 A resolution.
J.Mol.Biol., 205:529-544, 1989

PubMed Abstract: The crystal structure of the ferric form of myoglobin from the mollusc Aplysia limacina has been refined at 1.6 A resolution, by restrained crystallographic refinement methods. The crystallographic R-factor is 0.19. The tertiary structure of the molecule conforms to the common globin fold, consisting of eight alpha-helices. The N-terminal helix A and helix G deviate significantly from linearity. The distal residue is recognized as Val63 (E7), which, however, does not contact the heme directly. Moreover the sixth (distal) co-ordination position of heme iron is not occupied by a water molecule at neutrality, i.e. below the acid-alkaline transition point of A. limacina myoglobin. The heme group sits in its crevice in the conventional orientation and no signs of heme isomerism are evident. The iron atom is 0.26 A out of the porphyrin plane, with a mean Fe-N (porphyrin) distance of 2.01 A. The co-ordination bond to the proximal histidine has a length of 2.05 A, and forms an angle of 4 degrees with the heme normal. A plane containing the imidazole ring of the proximal His intersects the heme at an angle of 29 degrees with the (porphyrin) 4N-2N direction. Inspection of the structure of pH 9.0 indicates that a hydroxyl ion is bound to the Fe sixth co-ordination position.

PubMed: 2926816
DOI: 10.1016/0022-2836(89)90224-6

実験手法

X-RAY DIFFRACTION (2 Å)