BEM VINDOS! - Este blog é uma pequena viagem ao mundo do ensino e pesquisa em ciência. Espero que gostem, enviem comentários sobre as postagens, críticas e/ou sugestões.

Characterisation of an acid trehalase produced by the thermotolerant fungus Rhizopus microsporus var. rhizopodiformis: Biochemical properties and immunochemical localisation

FEMS MICROBIOLOGY LETTERS 251 (2005) 169–175


Ana Carla Medeiros Morato de Aquino, Simone Carvalho Peixoto-Nogueira, João Atílio Jorge, Héctor Francisco Terenzi, Maria de Lourdes Teixeira de Moraes Polizeli

An acid trehalase from Rhizopus microsporus var. rhizopodiformis was purified to apparent homogeneity. The molecular weight by SDS–PAGE (60 kDa) or Sephacryl S-200 filtration (105 kDa) suggested a homodimer. The carbohydrate content was 72%. Endoglycosidase H digestion resulted in one sharp band of 51.5 kDa in SDS–PAGE. pH and temperature optima were 4.5 and 45ºC, respectively. The isoelectric point was 6.69 and activation energy was 1.14 kcal mol-1. The enzyme was stable for 1 h at 50ºC and decayed at 60ºC (t50 of 1.3 min.). Apparent KM for trealose was 0.2 mM. Immunolocalisation studies showed the enzyme tightly packed at the surface of the cells.