Filling a cavity dramatically increases pressure stability of the c-Myb R2 subdomain.
Cavities or packing defects in proteins may generally be related with the dynamics and function of a protein. In the c-Myb R2 subdomain, its single cavity has been shown to be crucial for its DNA recognition. Cavities are also considered important in determining the pressure stability of a protein. In the present work, high-pressure proton nuclear magnetic resonance ((1)H NMR) spectroscopy at 750 MHz is used to study the effect of a cavity-filling mutation (V103L) on the stability of the c-Myb R2 subdomain in the pressure range between 1 and 3,700 bar at 5 degrees C. A dramatic increase in the pressure stability of the c-Myb R2 subdomain is attained, from which we estimate the cavity size to be 35.3 A(3), in good agreement with literature values. We also evaluated the increase in thermodynamic stability DeltaG(0)(1bar) from 5.35 kJ/mol to 7.34 kJ/mol by the mutation, giving a clear example of the effect of a cavity on the global stability of a globular protein.
Lassalle
M W
MW
Department of Molecular Science, Graduate School of Science and Technology, Kobe University, Kobe, Japan.
Yamada
H
H
Morii
H
H
Ogata
K
K
Sarai
A
A
Akasaka
K
K
D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009154:Mutation / Q000235:genetics; D011312:Pressure; D011487:Protein Conformation; D011489:Protein Denaturation; D017510:Protein Folding; D020673:Protein Renaturation; D017434:Protein Structure, Tertiary; D020598:Proto-Oncogene Proteins c-myb / Q000737:chemistry* / Q000235:genetics; D013816:Thermodynamics
D020598:Proto-Oncogene Proteins c-myb