Functional consequences of haem orientational disorder in sperm-whale and yellow-fin-tuna myoglobins

Ligand-binding kinetics of native and reconstituted sperm-whale myoglobin were studied in relation to haem orientational disorder by rapid kinetic methods. In addition, native yellow-fin-tuna myoglobin with significant amount of haem disorder was also used. The O2 dissociation and association rates were found for the proteins with different degrees of haem disorder, and these results suggest that the isomers are characterized by almost identical kinetic parameters. Rates of CO recombination after photolysis were also identical for the two orientational isomers. The results clearly indicate that the rotation of the haem about the alpha-gamma meso axis has little or no effect on the ligand-binding properties of these myoglobins.

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Kinetics of ligand binding to Pseudoterranova decipiens and Ascaris suum hemoglobins and to Leu-29–>Tyr sperm whale myoglobin mutant

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)85292-4 ◽

1993 ◽

Vol 268 (23) ◽

pp. 16993-16998

Author(s):

Q.H. Gibson ◽

R. Regan ◽

J.S. Olson ◽

T.E. Carver ◽

B. Dixon ◽

...

Keyword(s):

Ligand Binding ◽

Ascaris Suum ◽

Sperm Whale ◽

Pseudoterranova Decipiens ◽

Kinetics Of ◽

Sperm Whale Myoglobin

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The effects of amino acid substitution at position E7 (residue 64) on the kinetics of ligand binding to sperm whale myoglobin.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)39749-2 ◽

1990 ◽

Vol 265 (6) ◽

pp. 3168-3176 ◽

Cited By ~ 2

Author(s):

R J Rohlfs ◽

A J Mathews ◽

T E Carver ◽

J S Olson ◽

B A Springer ◽

...

Keyword(s):

Amino Acid ◽

Ligand Binding ◽

Amino Acid Substitution ◽

Sperm Whale ◽

Kinetics Of ◽

Sperm Whale Myoglobin

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The role of Val68(E11) in ligand binding to sperm whale myoglobin. Site-directed mutagenesis of a synthetic gene.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)38467-4 ◽

1990 ◽

Vol 265 (20) ◽

pp. 11788-11795

Author(s):

K D Egeberg ◽

B A Springer ◽

S G Sligar ◽

T E Carver ◽

R J Rohlfs ◽

...

Keyword(s):

Ligand Binding ◽

Sperm Whale ◽

Site Directed Mutagenesis ◽

Synthetic Gene ◽

Directed Mutagenesis ◽

Sperm Whale Myoglobin

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Spectroscopic analyses of the binding kinetics of 15d-PGJ2 to the PPARγ ligand-binding domain by multi-wavelength global fitting

Biochemical Journal ◽

10.1042/bj20050930 ◽

2006 ◽

Vol 393 (3) ◽

pp. 749-755 ◽

Cited By ~ 14

Author(s):

Takuma Shiraki ◽

Takashi S. Kodama ◽

Sayaka Shiki ◽

Tatsuo Nakagawa ◽

Hisato Jingami

Keyword(s):

Ligand Binding ◽

Intermediate State ◽

Covalent Binding ◽

Binding Domain ◽

Ligand Binding Domain ◽

Binding Kinetics ◽

Multi Wavelength ◽

Lipid Metabolites ◽

Kinetics Of ◽

Global Fitting

PPARγ (peroxisome proliferator-activated receptor γ) is a nuclear receptor that is activated by natural lipid metabolites, including 15d-PGJ2 (15-deoxy-Δ12,14-prostaglandin J2). We previously reported that several oxidized lipid metabolites covalently bind to PPARγ through a Michael-addition to activate transcription. To separate the ligand-entering (dock) and covalent-binding (lock) steps in PPARγ activation, we investigated the binding kinetics of 15d-PGJ2 to the PPARγ LBD (ligand-binding domain) by stopped-flow spectroscopy. We analysed the spectral changes of 15d-PGJ2 by multi-wavelength global fitting based on a two-step chemical reaction model, in which an intermediate state represents the 15d-PGJ2–PPARγ complex without covalent binding. The extracted spectrum of the intermediate state in wild-type PPARγ was quite similar to the observed spectrum of 15d-PGJ2 in the C285S mutant, which cannot be activated by 15d-PGJ2, indicating that the complex remains in the inactive, intermediate state in the mutant. Thus ‘lock’ rather than ‘dock’ is one of the critical steps in PPARγ activation by 15d-PGJ2.

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