1MCY

SPERM WHALE MYOGLOBIN (MUTANT WITH INITIATOR MET AND WITH HIS 64 REPLACED BY GLN, LEU 29 REPLACED BY PHE

1MCY の概要

• エントリーDOI: 10.2210/pdb1mcy/pdb
• 分子名称: MYOGLOBIN (CARBONMONOXY), SULFATE ION, PROTOPORPHYRIN IX CONTAINING FE, ... (5 entities in total)
• 機能のキーワード: heme, oxygen transport, respiratory protein, myoglobin (carbonmonoxy)
• 由来する生物種: Physeter catodon (sperm whale)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 18130.70

構造登録者

Li, T.,Phillips Jr., G.N. (登録日: 1995-07-19, 公開日: 1995-12-07, 最終更新日: 2024-02-14)

主引用文献

Zhao, X.,Vyas, K.,Nguyen, B.D.,Rajarathnam, K.,La Mar, G.N.,Li, T.,Phillips, G.N.,Eich, R.F.,Olson, J.S.,Ling, J.
A double mutant of sperm whale myoglobin mimics the structure and function of elephant myoglobin.
J.Biol.Chem., 270:20763-20774, 1995

PubMed Abstract: The functional, spectral, and structural properties of elephant myoglobin and the L29F/H64Q mutant of sperm whale myoglobin have been compared in detail by conventional kinetic techniques, infrared and resonance Raman spectroscopy, 1H NMR, and x-ray crystallography. There is a striking correspondence between the properties of the naturally occurring elephant protein and those of the sperm whale double mutant, both of which are quite distinct from those of native sperm whale myoglobin and the single H64Q mutant. These results and the recent crystal structure determination by Bisig et al. (Bisig, D. A., Di Iorio, E. E., Diederichs, K., Winterhalter, K. H., and Piontek, K. (1995) J. Biol. Chem. 270, 20754-20762) confirm that a Phe residue is present at position 29 (B10) in elephant myoglobin, and not a Leu residue as is reported in the published amino acid sequence. The single Gln64(E7) substitution lowers oxygen affinity approximately 5-fold and increases the rate of autooxidation 3-fold. These unfavorable effects are reversed by the Phe29(B10) replacement in both elephant myoglobin and the sperm whale double mutant. The latter, genetically engineered protein was originally constructed to be a blood substitute prototype with moderately low O2 affinity, large rate constants, and increased resistance to autooxidation. Thus, the same distal pocket combination that we designed rationally on the basis of proposed mechanisms for ligand binding and autooxidation is also found in nature.

PubMed: 7657659
DOI: 10.1074/jbc.270.35.20781

実験手法

X-RAY DIFFRACTION (1.7 Å)