title: Monotopic modifications derived from in vitro glycation of albumin with ribose.
abstract: Post-translational modifications are significant reactions that occur to proteins. One of these modifications is a non-enzymatic reaction between the oxo-group(s) of sugars and amino-group(s) of protein - glycation. This reaction plays an important role in the chronic complications of diabetes mellitus, or in the aging process of organisms, that is, it has an important role in the pathophysiology and "normal" physiology of animals. In the work presented here, we studied the glycation of albumins (HSA and BSA). Methodologically, we used nano-LC coupled to a QTOF mass spectrometer. In vitro-modified proteins were cleaved by trypsin and the arising peptides were separated on a C(18) nano column with a trap-column. Peptides and their modifications were analysed with a high-resolution QTOF mass spectrometer with a mass determination precision of better than 5 ppm. Non-enzymatic in vitro reaction products between albumin and ribose were identified. Besides well-known carboxymethyl lysine, new modifications were determined - creating mass shifts of 78 and 218. The origin of the first modification is discussed and its possible structure is presented. In addition, a mass shift of 132 belonging to a Schiff base was also identified. The location of all the modifications within the structure of the proteins was determined and their reactivity to various oxo-compounds was also examined.
authors.affiliation: Institute of Physiology, Academy of Sciences of the Czech Republic v.v.i, Prague, Czech Republic.
authors.forename: Statis
authors.initials: S
authors.lastname: Pataridis
authors.forename: Zdeňka
authors.initials: Z
authors.lastname: Stastná
authors.forename: Pavla
authors.initials: P
authors.lastname: Sedláková
authors.forename: Ivan
authors.initials: I
authors.lastname: Mikšík
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D019075:Electrophoresis, Capillary; D017127:Glycation End Products, Advanced / Q000737:chemistry* / Q000378:metabolism*; D006031:Glycosylation; D006801:Humans; D008969:Molecular Sequence Data; D012266:Ribose / Q000737:chemistry* / Q000378:metabolism*; D012709:Serum Albumin / Q000737:chemistry* / Q000378:metabolism*; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D017127:Glycation End Products, Advanced; D012709:Serum Albumin; D012266:Ribose