Purification and properties of beta-galactosidase from Aspergillus nidulans.
Beta-Galactosidase from mycelial extract of Aspergillus nidulans has been purified by substrate affinity chromatography and used to obtain anti-beta-galactosidase polyclonal antibodies. A. nidulans growing in lactose as carbon source synthesizes one active form of beta-galactosidase which seems to be a multimeric enzyme of 450 kDa composed of monomers with 120 and 97 kDa. Although the enzyme was not released to the culture medium, some enzymatic activity was detected in a cell-wall extract, thus suggesting that it can be an extracellular enzyme. Beta-Galactosidase of A. nidulans is a very unstable enzyme with an optimum pH value of 7.5 and an optimum temperature of 30 degrees C. It was only active against beta-galactoside substrates like lactose and p-nitrophenyl-beta-D-galactoside (PNPG).
Díaz
M
M
Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Alcalá de Henares, Madrid, España.
Pedregosa
A M
AM
de Lucas
J R
JR
Torralba
S
S
Monistrol
I F
IF
Laborda
F
F
D001233:Aspergillus nidulans / Q000201:enzymology*; D001616:beta-Galactosidase / Q000032:analysis / Q000302:isolation & purification*
D001616:beta-Galactosidase