title: Direct monitoring of albumin lysine-525 N-homocysteinylation in human serum by liquid chromatography/mass spectrometry.
abstract: A posttranslational protein modification by homocysteine-thiolactone (N-homocysteinylation) is linked to human vascular and neurodegenerative diseases. Although chemical and immunological methods are available to detect and quantify the extent of protein N-homocysteinylation, the determination of site-specific N-homocysteinylation in vivo remains challenging. Here we describe a liquid chromatography/mass spectrometry method that monitors the extent of N-homocysteinylation at albumin lysine-525 in vivo directly in human serum. Using this method, we found that the extent of lysine-525 N-homocysteinylation was significantly increased in patients with cystathionine beta-synthase deficiency.
authors.affiliation: Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznań, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Sikora
authors.forename: Lukasz
authors.initials: L
authors.lastname: Marczak
authors.forename: Tomasz
authors.initials: T
authors.lastname: Twardowski
authors.forename: Maciej
authors.initials: M
authors.lastname: Stobiecki
authors.forename: Hieronim
authors.initials: H
authors.lastname: Jakubowski
mesh_terms: D000595:Amino Acid Sequence; D002853:Chromatography, Liquid / Q000379:methods*; D003541:Cystathionine beta-Synthase / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D006710:Homocysteine / Q000097:blood; D006801:Humans; D008239:Lysine / Q000378:metabolism*; D013058:Mass Spectrometry / Q000379:methods*; D011499:Protein Processing, Post-Translational; D012709:Serum Albumin / Q000378:metabolism*
chemical_list: D012709:Serum Albumin; D006710:Homocysteine; D003541:Cystathionine beta-Synthase; D008239:Lysine