Effects of⁶⁰Co γ-irradiation on Chondromucoprotein

Abstract

Pulse radiolysis and 60Co gamma-radiolysis have been used to study the effects of ionizing radiations on the protein-polysaccharide complex, chondromucoprotein. Both hydroxyl radicals and hydrated electrons readily react with the complex, with second-order rate-constants of 4-55 X 10(8)M-1s-1, respectively. Depolymerization of the carbohydrate component, which is initiated by reaction of OH, readily occurs after irradiation in aqueous solution, as is evidenced by an increase in the formation of reducing-end groups and a decrease in the viscosity of the solution. The ability of the anionic carbohydrate component to bind cationic counter-ions also decreases.

Molecular engineering of glycosaminoglycan chemistry for biomolecule delivery

“…Chemical degradation reactions were originally explored to uncover the structure of GAGs by breaking the polymer into sugar monomers or oligomers for subsequent downstream analysis. Reaction conditions include harsh treatments with highly concentrated hydroxides [165], nitrous acid treatment [166–168], radiolysis [169], hydrazinolysis [170], hydrogen peroxide treatment [171], treatment with ozone and sunlight [172] and the application of Fenton’s reagents (Fe 2+ /H 2 O 2 ) [173]. …”

Electron beam fragmentation of bacterial polysaccharides as a method of producing oligosaccharides for the preparation of conjugate vaccines

“…In a quest for a simple and general fragmentation method that could be applied to a wide variety of PSs irrespective of the chemical structure, we have focused our research on the effect of ionizing radiation on PSs. Radiation‐induced chemical alterations of biopolymers, including chain scission, have been extensively studied in molecules such as glycosaminoglycans [23–26], proteins [27], DNA [28], and synthetic glyco‐co‐polymers [29], but the reports on the effect of the radiation on chemical and antigenic properties of bacterial PSs are scarce and limited only to LPS of Escherichia coli [30–32].…”

Effects of Gamma and Electron Radiation on the Structural Integrity of Organic Molecules and Macromolecular Biomarkers Measured by Microarray Immunoassays and Their Astrobiological Implications

“…, epitopes), much can be learnt from them regarding the effects of ionizing radiation on the chemistry and the structure of organic molecules, including biogenic molecules. There is extensive literature reporting that the radiation sensitivity is dependent on the size of the macromolecules (Kempner and Schlegel, 1979 ; Venter et al , 1983 ; Peters et al , 1984 ), and the fragmentation effect of radiation on biopolymers such as proteins (Miller et al , 1998 ), DNA (Rydberg, 1996 ), or polysaccharides (Edwards et al , 1977 ; Atrous et al , 2015 ) has also been reported. Some experimental studies in the planetary exploration context showed a linear increase of the radiolysis constant with the molecular weight in small molecules such as amino acids (Kminek and Bada, 2006 ).…”

“…Ionizing radiation can also penetrate meters into regolith or ice, and can cause structural and chemical changes on organic and biological molecules (Dartnell et al , 2007b ). For example, direct impacts by radiation produce fragmentation but not dissociation on the native structure of proteins (Miller et al , 1998 ), and polysaccharides are depolymerized into small fragments after irradiating with gamma rays (Edwards et al , 1977 ), and their antigenic properties are severely affected in a radiation dose-dependent manner (Csako et al , 1987 ). In the case of nucleic acids, ionizing radiation is known to cause cross-linking and strand breaks in DNA (Rydberg, 1996 ) and RNA molecules (Hutchinson et al , 1963 ).…”