title: Carnosinases, their substrates and diseases.
abstract: Carnosinases are Xaa-His dipeptidases that play diverse functions throughout all kingdoms of life. Human isoforms of carnosinase (CN1 and CN2) under appropriate conditions catalyze the hydrolysis of the dipeptides carnosine (β-alanyl-L-histidine) and homocarnosine (γ-aminobutyryl-L-histidine). Alterations of serum carnosinase (CN1) activity has been associated with several pathological conditions, such as neurological disorders, chronic diseases and cancer. For this reason the use of carnosinase levels as a biomarker in cerebrospinal fluid (CSF) has been questioned. The hydrolysis of imidazole-related dipeptides in prokaryotes and eukaryotes is also catalyzed by aminoacyl-histidine dipeptidases like PepD (EC 3.4.13.3), PepV (EC 3.4.13.19) and anserinase (EC 3.4.13.5). The review deals with the structure and function of this class of enzymes in physiological and pathological conditions. The main substrates of these enzymes, i.e., carnosine, homocarnosine and anserine (β-alanyl-3-methyl-L-histidine) will also be described.
authors.affiliation: Institute of Biostructure and Bioimaging, CNR, viale A. Doria 6, 95125 Catania, Italy. francesco.bellia@cnr.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Bellia
authors.affiliation: Department of Chemical Sciences, University of Catania, viale A. Doria 6, 95125 Catania, Italy. gr.vecchio@unict.it.
authors.forename: Graziella
authors.initials: G
authors.lastname: Vecchio
authors.affiliation: Institute of Biostructure and Bioimaging, CNR, viale A. Doria 6, 95125 Catania, Italy. erizzarelli@unict.it.
authors.forename: Enrico
authors.initials: E
authors.lastname: Rizzarelli
mesh_terms: D002336:Carnosine / Q000031:analogs & derivatives / Q000378:metabolism; D004150:Dipeptidases / Q000097:blood / Q000737:chemistry* / Q000235:genetics; D004151:Dipeptides / Q000737:chemistry; D006801:Humans; D009369:Neoplasms / Q000201:enzymology* / Q000209:etiology / Q000473:pathology; D009422:Nervous System Diseases / Q000201:enzymology* / Q000209:etiology / Q000473:pathology; D011487:Protein Conformation; D013329:Structure-Activity Relationship; D013379:Substrate Specificity
chemical_list: D004151:Dipeptides; C005038:homocarnosine; D002336:Carnosine; C522928:CNDP1 protein, human; D004150:Dipeptidases