title: Enzymatic and metabolic characterization of the phosphoglycerate kinase deficiency associated with chronic hemolytic anemia caused by the PGK-Barcelona mutation.
abstract: Recently, we reported a new mutation of phosphoglycerate kinase (PGK), called PGK-Barcelona, which causes chronic hemolytic anemia associated with progressive neurological impairment. We found a 140T→A substitution that produces an Ile46Asn change located at the N-domain of the enzyme and we suggested that the decrease of the PGK activity is probably related to a loss of enzyme stability. In this paper, by analyzing whole hemolysates and cloned enzymes, we show that both enzymes possess similar kinetic properties (although some differences are observed in the Km values) and the same electrophoretic mobility. However, PGK-Barcelona has higher thermal instability. Therefore, we confirm that the decrease of the red blood cell (RBC) PGK activity caused by the PGK-Barcelona mutation is more closely related to a loss of enzyme stability than to a decrease of enzyme catalytic function. Furthermore, we have measured the levels of glycolytic metabolites and adenine nucleotides in the RBC from controls and from the patient. The increase of 2,3-bisphosphoglycerate and the decrease of ATP RBC levels are the only detected metabolic changes that could cause hemolytic anemia.
authors.affiliation: Unitat de Bioquímica i Biologia Molecular, Departament de Ciències Fisiològiques I, Facultat de Medicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Universitat de Barcelona, Spain.
authors.forename: María José
authors.initials: MJ
authors.lastname: Ramírez-Bajo
authors.forename: Ada
authors.initials: A
authors.lastname: Repiso
authors.forename: Pablo Pérez de
authors.initials: PP
authors.lastname: la Ossa
authors.forename: Elisenda
authors.initials: E
authors.lastname: Bañón-Maneus
authors.forename: Pedro
authors.initials: P
authors.lastname: de Atauri
authors.forename: Fernando
authors.initials: F
authors.lastname: Climent
authors.forename: Joan-Lluís Vives
authors.initials: JL
authors.lastname: Corrons
authors.forename: Marta
authors.initials: M
authors.lastname: Cascante
authors.forename: José
authors.initials: J
authors.lastname: Carreras
mesh_terms: D019794:2,3-Diphosphoglycerate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000743:Anemia, Hemolytic / Q000150:complications* / Q000235:genetics* / Q000378:metabolism*; D002908:Chronic Disease; D004795:Enzyme Stability / Q000502:physiology; D004912:Erythrocytes / Q000201:enzymology; D006019:Glycolysis / Q000502:physiology; D006801:Humans; D007700:Kinetics; D009154:Mutation; D010735:Phosphoglycerate Kinase / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*; D013696:Temperature
chemical_list: D019794:2,3-Diphosphoglycerate; D000255:Adenosine Triphosphate; D010735:Phosphoglycerate Kinase