Dataset Information

Structural and enzymatic characterization of the streptococcal ATP/diadenosine polyphosphate and phosphodiester hydrolase Spr1479/SapH.

ABSTRACT: Spr1479 from Streptococcus pneumoniae R6 is a 33-kDa hypothetical protein of unknown function. Here, we determined the crystal structures of its apo-form at 1.90 Å and complex forms with inorganic phosphate and AMP at 2.30 and 2.20 Å, respectively. The core structure of Spr1479 adopts a four-layer ????-sandwich fold, with Fe(3+) and Mn(2+) coordinated at the binuclear center of the active site (similar to metallophosphoesterases). Enzymatic assays showed that, in addition to phosphodiesterase activity for bis(p-nitrophenyl) phosphate, Spr1479 has hydrolase activity for diadenosine polyphosphate (Ap(n)A) and ATP. Residues that coordinate with the two metals are indispensable for both activities. By contrast, the streptococcus-specific residue Trp-67, which binds to phosphate in the two complex structures, is indispensable for the ATP/Ap(n)A hydrolase activity only. Moreover, the AMP-binding pocket is conserved exclusively in all streptococci. Therefore, we named the protein SapH for streptococcal ATP/Ap(n)A and phosphodiester hydrolase.

SUBMITTER: Jiang YL

PROVIDER: S-EPMC3195627 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Structural and enzymatic characterization of the streptococcal ATP/diadenosine polyphosphate and phosphodiester hydrolase Spr1479/SapH.

Jiang Yong-Liang YL Zhang Jun-Wei JW Yu Wei-Li WL Cheng Wang W Zhang Chen-Chen CC Frolet Cecile C Di Guilmi Anne-Marie AM Vernet Thierry T Zhou Cong-Zhao CZ Chen Yuxing Y

The Journal of biological chemistry 20110823 41

Spr1479 from Streptococcus pneumoniae R6 is a 33-kDa hypothetical protein of unknown function. Here, we determined the crystal structures of its apo-form at 1.90 Å and complex forms with inorganic phosphate and AMP at 2.30 and 2.20 Å, respectively. The core structure of Spr1479 adopts a four-layer αββα-sandwich fold, with Fe(3+) and Mn(2+) coordinated at the binuclear center of the active site (similar to metallophosphoesterases). Enzymatic assays showed that, in addition to phosphodiesterase ac ...[more]

PMID: 21865160

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Dataset Information

Structural and enzymatic characterization of the streptococcal ATP/diadenosine polyphosphate and phosphodiester hydrolase Spr1479/SapH.

Publications

Structural and enzymatic characterization of the streptococcal ATP/diadenosine polyphosphate and phosphodiester hydrolase Spr1479/SapH.

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