2018-08-242018-08-242011GALDINO, Alexsandro Sobreira; SILVA, Roberto Nascimento; LOTTERMANN, Muriele Taborda; ALVARES, Alice Cunha Morales; MORAES, Lídia Maria Pepe de; TORRES, Fernando Araripe Gonçalves; FREITAS, Sonia Maria de; ULHOA, Cirano Jose. Biochemical and structural characterization of Amy1, an alpha-amylase from Cryptococcus flavus expressed in Saccharomyces cerevisiae. Enzyme Research, London, v. 2011, p. 1-7, 2011.2090-0406e- 2090-0414http://repositorio.bc.ufg.br/handle/ri/15732An extracellular alpha-amylase (Amy1) whose gene from Cryptococcus flavus was previously expressed in Saccharomyces cerevisiae was purified to homogeneity (67 kDa) by ion-exchange and molecular exclusion chromatography. The enzyme was activated by NH 4 + and inhibited by Cu +2 and Hg +2 . Significant biochemical and structural discrepancies between wild-type and recombinant α- amylase with respect to K m values, enzyme specificity, and secondary structure content were found. Far-UV CD spectra analysis at pH 7.0 revealed the high thermal stability of both proteins and the difference in folding pattern of Amy1 compared with wild-type amylase from C. flavus, which reflected in decrease (10-fold) of enzymatic activity of recombinant protein. Despite the differences, the highest activity of Amy1 towards soluble starch, amylopectin, and amylase, in contrast with the lowest activity of Amy1 w , points to this protein as being of paramount biotechnological importance with many applications ranging from food industry to the production of biofuels.engAcesso AbertoArtigo10.4061/2011/157294