Purification and Characterization of the alpha-Glucosidase Produced by Thermophilic Fungus Thermoascus aurantiacus CBMAI 756

Autor(es)

Azevedo Carvalho, Ana Flavia ^[1] ; Boscolo, Mauricio ^[1] ; da Silva, Roberto ^[1] ; Ferreira, Henrique ^[1] ; Gomes, Eleni ^[1]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ Unesp, Lab Bichem & Appl Microbiol, BR-15054000 Sao Jose Do Rio Preto - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF MICROBIOLOGY; v. 48, n. 4, p. 452-459, AUG 2010.
• Área do conhecimento: Ciências Biológicas - Microbiologia
• Citações Web of Science: 4
• Assunto(s): Enzimas alfa-Glucosidases Hidrolases Saccharomyces cerevisiae Thermoascus

Resumo

An alpha-glucosidase enzyme produced by the fungus Thermoascus aurantiacus CBMAI 756 was purified by ultra filtration, ammonium sulphate precipitation, and chromatography using Q Sepharose, Sephacryl S-200, and Superose 12 columns. The apparent molecular mass of the enzyme was 83 kDa as determined in gel electrophoresis. Maximum activity was observed at pH 4.5 at 70 degrees C. Enzyme showed stability stable in the pH range of 3.0-9.0 and lost 40% of its initial activity at the temperatures of 40, 50, and 60 C. In the presence of ions Na(+), Ba(2+), Co(2+), Ni(2+), Mg(2+), Mn(2+), Al(3+), Zn(2+), Ca(2+) this enzyme maintained 90-105% of its maximum activity and was inhibited by Cr(3+), Ag(+), and Hg(2+). The enzyme showed a transglycosylation property, by the release of oligosaccharides after 3 h of incubation with maltose, and specificity for short maltooligosaccharides and alpha-PNPG. The K(m) measured for the a-glucosidase was 0.07 mu M, with a V(max) of 318.0 mu mol/min/mg. (AU)

• Processo FAPESP: 10/12624-0 - Aplicação de métodos físico-químicos e enzimáticos na sacarificação do bagaço de cana: estudos de microrganismos, processos fermentativos relacionados e métodos de hidrólise
• Beneficiário: Eleni Gomes
• Linha de fomento: Auxílio à Pesquisa - Temático