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Cloning, purification and characterisation of a recombinant purine nucleoside phosphorylase from Bacillus halodurans Alk36.

ABSTRACT: A purine nucleoside phosphorylase from the alkaliphile Bacillus halodurans Alk36 was cloned and overexpressed in Escherichia coli. The enzyme was purified fivefold by membrane filtration and ion exchange. The purified enzyme had a V (max) of 2.03 x 10(-9) s (-1) and a K (m) of 206 microM on guanosine. The optimal pH range was between 5.7 and 8.4 with a maximum at pH 7.0. The optimal temperature for activity was 70 degrees C and the enzyme had a half life at 60 degrees C of 20.8 h.

SUBMITTER: Visser DF

PROVIDER: S-EPMC2832885 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Cloning, purification and characterisation of a recombinant purine nucleoside phosphorylase from Bacillus halodurans Alk36.

Visser Daniel F DF Hennessy Fritha F Rashamuse Konanani K Louw Maureen E ME Brady Dean D

Extremophiles : life under extreme conditions 20100301 2

A purine nucleoside phosphorylase from the alkaliphile Bacillus halodurans Alk36 was cloned and overexpressed in Escherichia coli. The enzyme was purified fivefold by membrane filtration and ion exchange. The purified enzyme had a V (max) of 2.03 x 10(-9) s (-1) and a K (m) of 206 microM on guanosine. The optimal pH range was between 5.7 and 8.4 with a maximum at pH 7.0. The optimal temperature for activity was 70 degrees C and the enzyme had a half life at 60 degrees C of 20.8 h. ...[more]

PMID: 20063024

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