Molecular analysis of two acidic proteinases pumAe and pumAi and aminopeptidase pumAPE from Ustilago maydis: enzymes purification and differential expression
Fecha
2006Autor
Versión
Acceso abierto / Sarbide irekia
Tipo
Contribución a congreso / Biltzarrerako ekarpena
Versión
Versión publicada / Argitaratu den bertsioa
Impacto
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nodoi-noplumx
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Resumen
Proteolytic system of Ustilago maydis was recently partially described (Mercado-Flores et al., 2003).
Two acidic proteinases pumAe (extracellular) and pumAi (intracellular) and aminopeptidase
pumAPE were detected and purified from the haploid phase of U. maydis. Purification consisted of
ammonium sulphate fractionation and different chromatographic steps. Molecular masses were estimated:
58 k ...
[++]
Proteolytic system of Ustilago maydis was recently partially described (Mercado-Flores et al., 2003).
Two acidic proteinases pumAe (extracellular) and pumAi (intracellular) and aminopeptidase
pumAPE were detected and purified from the haploid phase of U. maydis. Purification consisted of
ammonium sulphate fractionation and different chromatographic steps. Molecular masses were estimated:
58 kDa for pumAPE, 72 kDa for pumAe and 35.3 kDa for pumAi. Enzymatic activity was optimal
at pH 7.0 and 35 ºC for pumAPE and 4.0 for the two proteinases. pumAPE was inhibited by
EDTA-Na2, 1,10-phenanthroline, bestantin, PMSF and several divalent cations, while proteinase
pumAi was inhibited by pepstatine A, also finding that yeast-to-mycelium transition was inhibited by
Pepstatine A in the culture medium. Primers were designed in order to amplify the gene APEum encoding
pumAPE and PRAum gene encoding pumAi, and they were used as probes in a Southern blot.
One copy of each gene was detected by genome in several strains. Differential expression of APEum
was assessed under different physiological conditions, detecting high expression levels on media supplemented
with corn infusion, proline, peptone and ammonium sulphate. PRAum is expressed when
cells are exposed to corn infusion and ammonium sulphate. [--]
Materias
Ustilago maydis,
Molecular analysis
Editor
Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Publicado en
Antonio G. Pisabarro and Lucía Ramírez (eds.): VI Meeting on Genetics and Cellular Biology of Basidiomycetes (GCBB-VI). Pamplona: Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006.
Notas
Comunicación presentada al VI Meeting on Genetics and Cellular Biology of Basidiomycetes (GCBB-VI), organizado por y celebrado en la Universidad Pública de Navarra el 3-6 de junio de 2005.
Entidades Financiadoras
C. Hernández-Rodríguez
and L. Villa-Tanaca received COFAA, and EDI (IPN) supports.
This work was supported by grant CGPI 20050005, IPN, Mexico. L. Villa-
Tanaca was hired by “Programa Institucional de Contratación de Personal
Académico de Excelencia para el Reforzamiento del Posgrado, IPN”.