RADIOLYTIC INACTIVATION OF CHYMOTRYPSINOGEN BY $sup 60$Co $gamma$-RAYS

Journal Article · Sat Jun 01 04:00:00 EDT 1963 · Nippon Kagaku Zasshi (Japan) Formerly Nippon Kagaku Kaishi (1921- 47) Merged with Kogyo Kagaku Zasshi to form Nippon Kagaku Kaishi

OSTI ID:4097328

Takisawa, M; Matsu, J

Co/sup 60/ gamma rays impinged upon a 0.01N sulfuric acid solution of chymotrypsinogen. Radiolytic inactivation was followed either by a polarographic method or by the spectrophotometric method. The radiolytic enzyme inactivation yield was found to be constant, i.e., G/inact/ = 0.5, and independent of the chymotrypsinogen concentration. However, G/inact/ seemed to increase with the protein concentration when it was measured by a change in polarographic wave. H, OH, and HO/sub 2/ radicals formed by the radiolysis of the water molecule may be exclusively involved in the inactivation of enzyme by the cleavage of bonds of rather small bond energy, e.g., hydrogen bond, and by the decomposition of some amino acid residues that may undergo bond fission with a minimum energy of activation. Stoichiometrically, the inactivation reaction may be regarded as the twoelectron donating (or accepting) reactions of OH, H, and HO/sub 2/ radicals. The fact that the radiolytic enzyme inactivation yield was always 0.5 independent of the presence of air in solution indicates that an energy absorption of 2 x 100 ev renders 1 molecule of protein inactive. Therefore, only one tryptophane residue in one chymotrypsin molecule would be contributing to the enzymic activation. (Nucl. Sci. Abstr. Japan, Vol. 2, No. 4)

• Research Organization: Inst. of Physical and Chemical Research, Tokyo
• NSA Number: NSA-18-008425
• OSTI ID: 4097328
• Journal Information: Nippon Kagaku Zasshi (Japan) Formerly Nippon Kagaku Kaishi (1921- 47) Merged with Kogyo Kagaku Zasshi to form Nippon Kagaku Kaishi, Journal Name: Nippon Kagaku Zasshi (Japan) Formerly Nippon Kagaku Kaishi (1921- 47) Merged with Kogyo Kagaku Zasshi to form Nippon Kagaku Kaishi Vol. Vol: 84; ISSN NPKZA
• Country of Publication: Country unknown/Code not available
• Language: Japanese

Related Subjects

ABSORPTION
ACIDITY
AMINO ACIDS
BINDING ENERGY
CHEMICAL REACTIONS
CHEMISTRY
CHYMOTRYPSINOGEN
COBALT 60
CONFIGURATION
DECOMPOSITION
EFFICIENCY
ENZYMES
EXCITATION
FREE RADICALS
GAMMA RADIATION
GAMMA SOURCES
HETEROCYCLICS
HYDROGEN
HYDROXIDES
IONIZATION
IRRADIATION
LIGHT
MEASURED VALUES
MOLECULES
PHOTOMETRY
POLAROGRAPHY
PRODUCTION
PROTEINS
QUANTITY RATIO
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIOBIOLOGY
RADIOLYSIS
RESIDUES
SOLUTIONS
SPECTROSCOPY
SULFURIC ACID
THERMODYNAMICS
TRYPTOPHAN
USES
VARIATIONS
WATER