Biomaterial Database

Adiabatic compressibility of myoglobin. Effect of axial ligand and denaturation. 1986

W P Leung, and K C Cho, and Y M Lo, and C L Choy

An ultrasonic technique has been employed to study the adiabatic compressibility of three metmyoglobin derivatives (aquomet-, fluoromet- and azidometmyoglobin) at neutral pH, and aquometmyoglobin as a function of pH in the frequency range of 1-10 MHz at 20 degrees C. No difference was observed in the adiabatic compressibility of the various derivatives. This indicates that the binding of different axial ligands to myoglobin does not affect significantly the conformational fluctuations of the protein. The finding is consistent with the results of the hydrogen exchange rate experiment, indicating that both types of measurements are useful for the study of protein dynamics. Upon acid-induced denaturation, the adiabatic compressibility of myoglobin drops from 5.3 X 10(-12) cm2/dyn to 0.5 X 10(-12) cm2/dyn. Plausible reasons for such a decrease are discussed.

UI	MeSH Term	Description	Entries
D008024	Ligands	A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)	Ligand
D009211	Myoglobin	A conjugated protein which is the oxygen-transporting pigment of muscle. It is made up of one globin polypeptide chain and one heme group.
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D011489	Protein Denaturation	Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.	Denaturation, Protein,Denaturations, Protein,Protein Denaturations
D006736	Horses	Large, hoofed mammals of the family EQUIDAE. Horses are active day and night with most of the day spent seeking and consuming food. Feeding peaks occur in the early morning and late afternoon, and there are several daily periods of rest.	Equus caballus,Equus przewalskii,Horse, Domestic,Domestic Horse,Domestic Horses,Horse,Horses, Domestic
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014465	Ultrasonics	A subfield of acoustics dealing in the radio frequency range higher than acoustic SOUND waves (approximately above 20 kilohertz). Ultrasonic radiation is used therapeutically (DIATHERMY and ULTRASONIC THERAPY) to generate HEAT and to selectively destroy tissues. It is also used in diagnostics, for example, ULTRASONOGRAPHY; ECHOENCEPHALOGRAPHY; and ECHOCARDIOGRAPHY, to visually display echoes received from irradiated tissues.	Ultrasonic