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Preliminary crystallographic studies of purine nucleoside phosphorylase from the cariogenic pathogen Streptococcus mutans.

ABSTRACT: The punA gene of the cariogenic pathogen Streptococcus mutans encodes purine nucleoside phosphorylase (PNP), which is a pivotal enzyme in the nucleotide-salvage pathway, catalyzing the phosphorolysis of purine nucleosides to generate purine bases and alpha-ribose 1-phosphate. In the present work, the PNP protein was expressed in Escherichia coli strain BL21 (DE3) in a soluble form at a high level. After purification of the PNP enzyme, the protein was crystallized using the sitting-drop vapour-diffusion technique; the crystals diffracted to 1.6 A resolution at best. The crystals belonged to space group H3, with unit-cell parameters a = b = 113.0, c = 60.1 A.

SUBMITTER: Hou QM

PROVIDER: S-EPMC2802883 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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Preliminary crystallographic studies of purine nucleoside phosphorylase from the cariogenic pathogen Streptococcus mutans.

Hou Qiao Ming QM Liu Xiang X Brostromer Erik E Li Lan Fen LF Su Xiao Dong XD

Acta crystallographica. Section F, Structural biology and crystallization communications 20091127 Pt 12

The punA gene of the cariogenic pathogen Streptococcus mutans encodes purine nucleoside phosphorylase (PNP), which is a pivotal enzyme in the nucleotide-salvage pathway, catalyzing the phosphorolysis of purine nucleosides to generate purine bases and alpha-ribose 1-phosphate. In the present work, the PNP protein was expressed in Escherichia coli strain BL21 (DE3) in a soluble form at a high level. After purification of the PNP enzyme, the protein was crystallized using the sitting-drop vapour-di ...[more]

PMID: 20054131

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