title: Effect of peroxynitrite on human serum albumin: a multi technique approach.
abstract: In this study, human serum albumin (HSA), the most abundant protein of blood plasma, was modified with varying concentrations of peroxynitrite. The peroxynitrite-induced changes in HSA was monitored by spectroscopy, SDS-PAGE, 1-anilinonaphthalene-8-sulfonic acid (ANS), thermal denaturation studies, and matrix-assisted laser desorption/inonization-time of flight mass spectrometry (MALDI-TOF MS). Aggregate formation was studied by thioflavin T binding and scanning electron microscopy (SEM). The results indicated formation of 3-nitrotyrosine, 6-nitrotryptophan, dityrosine, and carbonyls in modified samples and showed retarded mobility in SDS-polyacrylamide gel. Reduction in α-helicity and surface protein hydrophobicity confirmed the secondary and tertiary structure alterations in peroxynitrite-modified-HSA. Also, attachment of nitro group and increase in melting temperature was observed in modified sample. Furthermore, significant enhancement in the fluorescence intensity of ThT upon binding with peroxynitrite-modified-HSA and images under scanning electron microscope are suggestive of protein aggregation. It is, therefore, speculated that HSA modified by endogenously formed peroxynitrite might act as a trigger for nitration/aggregation and suggested the role of peroxynitrite-modified-HSA in SLE.
authors.affiliation: a Facuty of Medicine, Department of Biochemistry , J.N. Medical College, Aligarh Muslim University , Aligarh 202002 , UP , India.
authors.forename: Zarina
authors.initials: Z
authors.lastname: Arif
authors.affiliation: a Facuty of Medicine, Department of Biochemistry , J.N. Medical College, Aligarh Muslim University , Aligarh 202002 , UP , India.
authors.forename: Mir Yasir
authors.initials: MY
authors.lastname: Arfat
authors.affiliation: b Faculty of Medicine, Rajiv Gandhi Centre for Diabetes and Endocrinology , J.N. Medical College, Aligarh Muslim University , Aligarh 202002 , UP , India.
authors.forename: Km
authors.initials: K
authors.lastname: Neelofar
authors.affiliation: a Facuty of Medicine, Department of Biochemistry , J.N. Medical College, Aligarh Muslim University , Aligarh 202002 , UP , India.
authors.forename: Shafeeque
authors.initials: S
authors.lastname: Ahmad
authors.affiliation: a Facuty of Medicine, Department of Biochemistry , J.N. Medical College, Aligarh Muslim University , Aligarh 202002 , UP , India.
authors.forename: Asim
authors.initials: A
authors.lastname: Badar
authors.affiliation: a Facuty of Medicine, Department of Biochemistry , J.N. Medical College, Aligarh Muslim University , Aligarh 202002 , UP , India.
authors.forename: Md Adnan
authors.initials: MA
authors.lastname: Khan
authors.affiliation: a Facuty of Medicine, Department of Biochemistry , J.N. Medical College, Aligarh Muslim University , Aligarh 202002 , UP , India.
authors.forename: Asif
authors.initials: A
authors.lastname: Zaman
authors.affiliation: b Faculty of Medicine, Rajiv Gandhi Centre for Diabetes and Endocrinology , J.N. Medical College, Aligarh Muslim University , Aligarh 202002 , UP , India.
authors.forename: Jamal
authors.initials: J
authors.lastname: Ahmad
mesh_terms: D052160:Benzothiazoles; D001665:Binding Sites / Q000187:drug effects; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008855:Microscopy, Electron, Scanning; D030421:Peroxynitrous Acid / Q000737:chemistry* / Q000494:pharmacology; D066329:Protein Aggregates / Q000187:drug effects*; D011485:Protein Binding / Q000187:drug effects; D000075462:Serum Albumin, Human / Q000037:antagonists & inhibitors / Q000138:chemical synthesis* / Q000648:ultrastructure; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013057:Spectrum Analysis; D013844:Thiazoles / Q000737:chemistry
chemical_list: D052160:Benzothiazoles; D066329:Protein Aggregates; D013844:Thiazoles; D030421:Peroxynitrous Acid; C009462:thioflavin T; D000075462:Serum Albumin, Human
keywords: 3-nitrotyrosine; HSA; SLE; scanning electron microscopy