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

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

OSTI ID:4701918

Muroshima, K; Hashizume, H; Matsuura, N; Imahori, K; Takizawa, M

BS>The radioinduced biochemical inactivation and polarographic wave decrease of chymotrypsinogen were investigated in aqueous phase and the obtained radiochemical yields were discussed from a stoichiometric point of view based on radical theory of radiolysis. The yields of enzyme inactivation were independent over a wide range of chymotrypsinogen concentration, providing G-value 0.51. On the contrary, polarographic yields corresponding to numbers of functional cystine destroyed for each 100 ev of energy absorption, depended on the concentration of protein. The reciprocal plots of radiochemical yields in G-value against the reciprocal solute concentration yielded a straight line intersecting the coordinate axis of (1/G) at 0.5, that means the hypothecal G-value 2.00 for a perfect radical scavenging. At a gamma dose lower than 20 Krep, radicals generated by radiolysis of water are consumed entirely for enzyme inactivation, while polarographic cystine wave is left unchanged or even somewhat increases. Once enzyme activity is lost, marked decrease in cystine wave appears. Along with these observations differential absorption spectra of irradiated protein solution were measured at wave length about 280 and 290 m mu , showing that the destruction of tertiary structure and tryptophane residue of the protein could be detected at gamma -ray dose lower than 20 Krep. From the stoichiometric evidences the tertiary structure and tryptophane residue of the protein molecule seemed to be attacked prior to the functional cystine group and the degradation with no redox reaction could be ascribed to the direct transfer of radical recombination energy. (auth)

• Research Organization: Tokyo Univ.
• NSA Number: NSA-17-040885
• OSTI ID: 4701918
• 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
AMINO ACIDS
BIOCHEMISTRY
CHEMICAL REACTIONS
CHEMISTRY
CHYMOTRYPSINOGEN
COBALT 60
CONCENTRATION
CYSTINE
DECOMPOSITION
EFFICIENCY
ENZYMES
FREE RADICALS
FREQUENCY
G-VALUE
GAMMA RADIATION
GAMMA SOURCES
HETEROCYCLICS
IRRADIATION
MEASURED VALUES
ORGANIC NITROGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDATION
POLAROGRAPHY
PROTEINS
QUALITATIVE ANALYSIS
QUANTITY RATIO
RADIATION CHEMISTRY
RADIATION DOSES
RADIOLYSIS
REDUCTION
SOLUTIONS
SPECTRA
SPECTROSCOPY
STOICHIOMETRY
TRYPTOPHAN
WATER