title: Physicochemical studies on peroxynitrite-modified H3 histone.
abstract: Histones are DNA protective proteins and may adopt different structures under nitrosative stress. Peroxynitrite is a powerful oxidant and nitrating agent and has in vivo existence. In this communication, we report effect of peroxynitrite-mediated oxidation and nitration on the structure of calf thymus H3 histone. Fine details of peroxynitrite-modified H3 histone were worked out by UV, fluorescence, circular dichroism and Fourier-transformed infrared spectroscopy and polyacrylamide gel. The results revealed that peroxynitrite-mediated nitration and oxidation in H3 histone produced partially folded structure in comparison to the intrinsically disordered structure of native H3 histone. It may be concluded that the H3 histone, constituent of core histones, is highly sensitive to peroxynitrite and can adopt different structures under nitrosative stress in order to protect the packaged DNA from the deleterious insult of peroxynitrite.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Aligarh Muslim University (A.M.U.), Aligarh 202 002, Uttar Pradesh, India.
authors.forename: Kiran
authors.initials: K
authors.lastname: Dixit
authors.forename: M Asad
authors.initials: MA
authors.lastname: Khan
authors.forename: Y D
authors.initials: YD
authors.lastname: Sharma
authors.lastname: Moinuddin
authors.forename: Khursheed
authors.initials: K
authors.lastname: Alam
mesh_terms: D000818:Animals; D002417:Cattle; D055598:Chemical Phenomena / Q000187:drug effects*; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D004591:Electrophoresis, Polyacrylamide Gel; D006657:Histones / Q000378:metabolism*; D006868:Hydrolysis / Q000187:drug effects; D030421:Peroxynitrous Acid / Q000494:pharmacology*; D011489:Protein Denaturation / Q000187:drug effects; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014357:Trypsin / Q000494:pharmacology; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
chemical_list: D006657:Histones; D030421:Peroxynitrous Acid; D014443:Tyrosine; C007543:dityrosine; D014357:Trypsin