Artigo
Purification and properties of acid phosphatase (EC 3.1.3.2) secreted by strain 74A of the mould Neurospora crassa
Fecha
1996-01-01Registro en:
World Journal of Microbiology & Biotechnology. London: Rapid Science Publishers, v. 12, n. 1, p. 109-110, 1996.
0959-3993
10.1007/BF00327816
WOS:A1996TW25900027
Autor
Universidade de São Paulo (USP)
Universidade Estadual Paulista (Unesp)
Resumen
Both P-i-repressible acid phosphatases, IIb (mycelial) and IIc (extracellular), synthesized by Neurospora crassa and purified to apparent homogeneity by 7.5% PAGE, are monomers, are inhibited by 2 mM ZnCl2 and are nonspecifically stimulated by salts. However, the IIc form is activated by p-nitrophenylphosphate (in a negative cooperativity effect with a K-0.5 of 2.5 mM) whereas form IIb shows Michaelis kinetics, with a K-m of 0.5 mM. Thus, since both enzymatic forms may be expressed by the same gene (pho-3), it is possible that post-translational modifications lead to the excretion of an enzymatic form with altered Michaelis kinetics compared with the enzymatic form retained by the mycelium.