Purification and Characterization of an Alkaline Phosphatase Induced by Phosphorus Starvation in Common Bean (Phaseolus vulgaris L.) Roots

Two phosphatase isoforms from roots of the common bean(Phaseolus vulgaris L.) showed an increase in activity in responseto phosphate deficiency. One of them (APIII) was chosen for further purification through ionic exchange chromatography and preparative electrophoresis. The estimated molecular mass...

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Detalles Bibliográficos
Autores: Lorena Morales, Natalia Gutiérrez, Vanessa Maya, Carmen Parra, Eleazar Martínez-Barajas, Patricia Coello
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:México
Institución:Universidad Nacional Autónoma de México
Repositorio:Redalyc-UNAM
OAI Identifier:oai:redalyc.org:47523284013
Acceso en línea:https://www.redalyc.org/articulo.oa?id=47523284013
Access Level:acceso abierto
Palabra clave:Química
purification
pyrophosphate
Phaseolus vulgaris
Alkaline phosphatase
phosphate deficiency
Descripción
Sumario:Two phosphatase isoforms from roots of the common bean(Phaseolus vulgaris L.) showed an increase in activity in responseto phosphate deficiency. One of them (APIII) was chosen for further purification through ionic exchange chromatography and preparative electrophoresis. The estimated molecular mass of APIII was 35 kDa by both SDS-PAGE and gel filtration analyses, suggesting a monomeric form of the active enzyme. The phosphatase was classified as an alkaline phosphatase based on the requirement of pH 8 for optimum catalysis. It not only exhibited broad substrate specificity, with the most activity against pyrophosphate, but also effectively catalyzed the hydrolysis of polyphosphate, glucose-1-phosphate and phosphoenolpyruvate. Activity was completely inhibited by molybdate, vanadate and phosphate but was only partially inhibited by fluoride. Although divalent cations were not essential for the pyrophosphatase activity of this enzyme, the hydrolysis of pyrophosphate increased substantially in the presence of Mg2+.