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

ABSTRACT: 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.

SUBMITTER: Pasamontes L

PROVIDER: S-EPMC168464 | biostudies-other | 1997 May

REPOSITORIES: biostudies-other

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

Pasamontes L L Haiker M M Wyss M M Tessier M M van Loon A P AP

Applied and environmental microbiology 19970501 5

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 overexpress ...[more]

PMID: 9143104

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