albumin - publications
Monotopic modifications derived from in vitro glycation of albumin with ribose.
Electrophoresis. 2013 Apr 8;
Authors: Pataridis S, Stastná Z, Sedláková P, Mikšík I
Posttranslational 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, i.e. it has an important role in the pathophysiology and "normal" physiology of animals. In the work presented here, we studied the glycation of albumins (human serum albumin and bovine serum albumin). Methodologically, we used nano-liquid chromatography coupled to a Q-TOF mass spectrometer. In vitro-modified proteins were cleaved by trypsin and the arising peptides were separated on a C18 nano column with a trap-column. Peptides and their modifications were analysed with a high-resolution Q-TOF 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 carboxymethyllysine, 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.
PMID: 23564614 [PubMed - as supplied by publisher]