从产黄青霉RFC3深层发酵产生的胞外多聚半乳糖醛酸酶的纯化

Gomes Eleni, Leite Rodrigo Simões Ribeiro, da Silva Roberto, Silva Dênis

Laboratory of Biochemistry and Applied Microbiology, Ibilce, Universidade Estadual Paulista (Unesp), Rua Cristovao Colombo, 2265, Jd. Nazareth, São José do Rio Preto, SP, CEP 15054-000, Brazil.

Int J Microbiol. 2009;2009:631942. doi: 10.1155/2009/631942. Epub 2010 Feb 3.

An exo-PG obtained from Penicillium viridicatum in submerged fermentation was purified to homogeneity. The apparent molecular weight of the enzyme was 92 kDa, optimum pH and temperature for activity were pH 5 and 50-55 degrees C. The exo-PG showed a profile of an exo-polygalacturonase, releasing galacturonic acid by hydrolysis of pectin with a high degree of esterification (D.E.). Ions Ca(2+) enhanced the stability of enzyme and its activity by 30%. The K(m) was 1.30 in absence of Ca(2+) and 1.16 mg mL(-1) in presence of this ion. In relation to the V(max) the presence of this ion increased from 1.76 to 2.07 mumol min(-1)mg(-1).

通过深层发酵从绿青霉中获得的一种外切多聚半乳糖醛酸酶被纯化至同质。该酶的表观分子量为92 kDa，活性的最适pH和温度分别为pH 5以及50 - 55℃。该外切多聚半乳糖醛酸酶呈现出外切多聚半乳糖醛酸酶的特征，通过水解高度酯化（D.E.）的果胶释放半乳糖醛酸。Ca(2+)离子可将酶的稳定性及其活性提高30%。在不存在Ca(2+)时K(m)为1.30，在存在该离子时为1.16 mg mL(-1)。关于V(max)，该离子的存在使其从1.76增加至2.07 μmol min(-1)mg(-1)。