Gene cloning, purification, and characterization of a heat-stable phytase from the fungus Aspergillus fumigatus

作者:Pasamontes L*; Haiker M; Wyss M; Tessier M; vanLoon APGM
来源:Applied and Environmental Microbiology, 1997, 63(5): 1696-1700.
DOI:10.1128/aem.63.5.1696-1700.1997

摘要

The finding of heat-stable enzymes or the engineering of moderately thermostable enzymes into more stable ones by random or site-directed mutagenesis has become a main priority of modern biotechnology. We report here for the first time a heat-stable phytase able to withstand temperatures up to 100 degrees C over a period of 20 min, with a loss of only 10% of the initial enzymatic activity. The gene (phyA) encoding this heat-stable enzyme has been cloned from Aspergillus fumigatus and overexpressed in Aspergillus niger. The enzyme showed high activity with 4-nitrophenyl phosphate at a pH range of 3 to 5 and with phytic acid at a pH range of 2.5 to 7.5.

  • 出版日期1997-5