Penicillium chrysogenum extracellular acid phosphatase: purification and biochemical characterization.
An extracellular acid phosphatase (EC 3.1.3.2) from crude culture filtrate of Penicillium chrysogenum was purified to homogeneity using high-performance ion-exchange chromatography and size-exclusion chromatography. SDS-PAGE of the purified enzyme exhibited a single stained band at an Mr of approx. 57,000. The mobility of the native enzyme indicated the Mr to be 50,000, implying that the active form is a monomer. The isoelectric point of the enzyme was estimated to be 6.2 by isoelectric focusing. Like acid phosphatases from several yeasts and fungi the Penicillium enzyme was a glycoprotein. Removal of carbohydrate resulted in a protein band with an Mr of 50,000 as estimated by SDS-PAGE, suggesting that 12% of the mass of the enzyme was carbohydrate. The enzyme was catalytically active at temperatures ranging from 20 degrees C to 65 degrees C with a maximum activity at 60 degrees C and the pH optimum was at 5.5. The Michaelis constant of the enzyme for p-nitrophenyl phosphate was 0.11 mM and it was inhibited competitively by inorganic phosphate (ki = 0.42 mM).
Haas
H
H
Institut für Mikrobiologie (Medizinische Fakultät), Universität Innsbruck, Austria.
Redl
B
B
Leitner
E
E
Stöffler
G
G
D000135:Acid Phosphatase / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism; D000596:Amino Acids / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D005656:Fungal Proteins / Q000032:analysis; D006023:Glycoproteins / Q000032:analysis; D006031:Glycosylation; D007525:Isoelectric Focusing; D007700:Kinetics; D008970:Molecular Weight; D010408:Penicillium chrysogenum / Q000201:enzymology*
D000596:Amino Acids; D005656:Fungal Proteins; D006023:Glycoproteins; D000135:Acid Phosphatase