RADIOLYSIS OF REDUCED DIPHOSPHOPYRIDINE NUCLEOTIDE IN AQUEOUS SOLUTION

Journal Article · Fri Nov 01 04:00:00 EST 1963 · Biochemistry (U.S.)

DOI:https://doi.org/10.1021/bi00906a021· OSTI ID:4133889

Adelstein, S J; Mee, L K

The radiolysis of DPNH solutions by 250-kvp x rays has been followed utilizing the absorption at 340 m mu , the corresponding fluorescence at 470 m mu , and the coenzymatic activity with alcohol dehydrogenase. All three parameters are decreased simultaneously and this reduction in DPNH concentration is neither linear nor logarithmic with dose. The coenzyme is protected in the presence of protein; the protection afforded by glutannic dehydrogenase, a DPNHbinding enzyme, is equal to that of serum albumin at the same weight concentration. The radiolysis of DPNH is independent of pH over the range 4.8--7.5 and is accompanied by an initial increase in pH, 260-m mu sbsorption, and cyanide reactivity. These observations suggest that DPNH is the first product formed which is, in turn, degraded logarithmically. A kinetic model for the radiolysis was formulated which gives a G(-DPNH) of 2.3 in air and 1.2 in oxygen-free nitrogen. (auth)

• Research Organization: Cambridge Univ., Eng.
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-003821
• OSTI ID: 4133889
• Journal Information: Biochemistry (U.S.), Journal Name: Biochemistry (U.S.) Vol. Vol: 2; ISSN BICHA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ABSORPTION
ACIDITY
ALBUMINS
CHEMISTRY
CYANIDES
DECOMPOSITION
DPNH
ENZYMES
FLUORESCENCE
G-VALUE
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHORUS COMPOUNDS
PROTEINS
PYRIDINES
RADIATION CHEMISTRY
RADIOLYSIS
REACTION KINETICS
SOLUTIONS
STABILITY
WATER
X RADIATION