INACTIVATION OF PEPSIN BY ROENTGEN RADIATION. II. EFFECT OF DIFFERENT ENZYME CONCENTRATIONS OR VARIOUS ORGANIC COMPOUNDS

Journal Article · Wed Jul 01 04:00:00 EDT 1959 · Radiation Research

DOI:https://doi.org/10.2307/3570735· OSTI ID:4249328

Loken, M K; Stenstrom, K W; Marvin, J F; Mosser, D G

The activity of pepsin exposed to roentgen irradiation was found to depend on the concentration of the enzyme during irradiation and the addition of organic compounds to the enzyme solution before radiation exposure. Pepsin was found to provide a significant selfprotection from radiation inactivation. Albumin protected pepsin from radiation to a degree which is comparable to that provided by pepsin itself. Hematoporphyrin, cysteamine, cysteine, glucose, and sucrose all protected the enzyme when present in the solution during the irradiation. Low concentrations of hematoporphyrin provided the same protection as that observed with concentrations of glucose which were about one hundred times higher. As the concentration of hematoporphyrin was increased above 10/sup -4/ M, its antiproteolytic effect became manifest so that its effectiveness as a radioprotective agent was impaired. At concentrations of 10/sup -3/ M or greater, cysteamine afforded the greatest protection of all chemicals used. (auth)

• Research Organization: Univ. of Minnesota, Minneapolis
• NSA Number: NSA-13-016719
• OSTI ID: 4249328
• Journal Information: Radiation Research, Journal Name: Radiation Research Journal Issue: 1 Vol. Vol: 11; ISSN 0033-7587
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ALBUMINS
AMINES
BIOLOGY AND MEDICINE
CHEMICAL REACTIONS
CYSTEAMINE
CYSTEINE
DECOMPOSITION
EFFICIENCY
ENZYMES
GLUCOSE
HEMATOPORPHYRIN
ORGANIC COMPOUNDS
PEPSIN
PIGMENTS
PORPHYRINS
PROTEINS
PROTEOLYSIS
QUANTITY RATIO
RADIATION EFFECTS
RADIATION PROTECTION
SOLUTIONS
SUCROSE
SUGARS
VARIATIONS
X RADIATION