Biomaterial Database

The radiation-induced inactivation of external yeast invertase in dilute aqueous solution. 1989

S Nagrani, and R H Bisby

Department of Biological Sciences, University of Salford, U.K.

The inactivation of external yeast invertase by irradiation in dilute aqueous solution has been investigated. The contributions of the individual radical species from water radiolysis to inactivation and amino acid degradation were estimated from the results of experiments in which solutions were saturated with nitrogen, nitrous oxide or oxygen, and on addition of hydroxyl radical scavengers. Under conditions where inactivation by hydroxyl radicals predominates, the rate of inactivation increased with increasing dose, indicating that in the initial stages of the radiolysis the mannose-rich oligosaccharide chains of the glycoprotein protect the polypeptide chain from radical attack. Amino acid analysis of the irradiated external invertase showed that there was significant destruction of tyrosine, phenylalanine, methionine and histidine residues. Destruction of methionine and histidine residues may be responsible for the free radical-induced inactivation of this enzyme.

UI	MeSH Term	Description	Entries
D003037	Cobalt Radioisotopes	Unstable isotopes of cobalt that decay or disintegrate emitting radiation. Co atoms with atomic weights of 54-64, except 59, are radioactive cobalt isotopes.	Radioisotopes, Cobalt
D004307	Dose-Response Relationship, Radiation	The relationship between the dose of administered radiation and the response of the organism or tissue to the radiation.	Dose Response Relationship, Radiation,Dose-Response Relationships, Radiation,Radiation Dose-Response Relationship,Radiation Dose-Response Relationships,Relationship, Radiation Dose-Response,Relationships, Radiation Dose-Response
D005609	Free Radicals	Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. Free radicals include reactive oxygen and nitrogen species (RONS). They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.	Free Radical
D005720	Gamma Rays	Penetrating, high-energy electromagnetic radiation emitted from atomic nuclei during NUCLEAR DECAY. The range of wavelengths of emitted radiation is between 0.1 - 100 pm which overlaps the shorter, more energetic hard X-RAYS wavelengths. The distinction between gamma rays and X-rays is based on their radiation source.	Gamma Wave,Gamma Radiation,Nuclear X-Rays,Radiation, Gamma,X-Rays, Nuclear,Gamma Radiations,Gamma Ray,Gamma Waves,Nuclear X Rays,Nuclear X-Ray,Ray, Gamma,Wave, Gamma,Waves, Gamma,X Rays, Nuclear,X-Ray, Nuclear
D006026	Glycoside Hydrolases	Any member of the class of enzymes that catalyze the cleavage of the glycosidic linkage of glycosides and the addition of water to the resulting molecules.	Endoglycosidase,Exoglycosidase,Glycohydrolase,Glycosidase,Glycosidases,Glycoside Hydrolase,Endoglycosidases,Exoglycosidases,Glycohydrolases,Hydrolase, Glycoside,Hydrolases, Glycoside
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
D012996	Solutions	The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Solution
D014867	Water	A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Hydrogen Oxide
D043324	beta-Fructofuranosidase	A glycoside hydrolase found primarily in PLANTS and YEASTS. It has specificity for beta-D-fructofuranosides such as SUCROSE.	beta-D-Fructofuranosidase,Acid Invertase,Invertase,Saccharase,Sacrosidase,Sucraid,Sucrose 6-Phosphate Hydrolase,beta-Fructosidase,6-Phosphate Hydrolase, Sucrose,Hydrolase, Sucrose 6-Phosphate,Invertase, Acid,Sucrose 6 Phosphate Hydrolase,beta D Fructofuranosidase,beta Fructofuranosidase,beta Fructosidase