The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Modification of horseradish peroxidase with bifunctional N-hydroxysuccinimide esters: effects on molecular stability》. Authors are Miland, Enda; Smyth, Malcolm R.; Fagain, Ciaran O..The article about the compound:Bis(2,5-dioxopyrrolidin-1-yl) O,O’-ethane-1,2-diyl disuccinatecas:70539-42-3,SMILESS:O=C(ON1C(CCC1=O)=O)CCC(OCCOC(CCC(ON2C(CCC2=O)=O)=O)=O)=O).Quality Control of Bis(2,5-dioxopyrrolidin-1-yl) O,O’-ethane-1,2-diyl disuccinate. Through the article, more information about this compound (cas:70539-42-3) is conveyed.
Horseradish peroxidase (HRP) has been chem. modified with the homobifunctional crosslinking reagents suberic acid N-hydroxysuccinimide ester (SA-NHS) and ethylene glycol bis-succinimidyl succinate (EG-NHS) yielding derivatives of native HRP with enhanced stability in a range of organic solvents. Modification did not cause any loss of activity. It has been shown that these modification reagents react specifically with the ε-amino groups of the six lysine residues of HRP. Stability increased with concentrations of EG-NHS up to a level of 4-5 mg ml-1. A marked difference was observed in the tryptophan fluorescence profiles of native and the EG-NHS peroxidases upon thermoinactivation at 65°. Both modified peroxidases exhibited improved resistance to the denaturant guanidine hydrochloride.
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Reference:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem