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Phosphate binding in the active centre of tomato multifunctional nuclease TBN1 and analysis of superhelix formation by the enzyme.

ABSTRACT: Tomato multifunctional nuclease TBN1 belongs to the type I nuclease family, which plays an important role in apoptotic processes and cell senescence in plants. The newly solved structure of the N211D mutant is reported. Although the main crystal-packing motif (the formation of superhelices) is conserved, the details differ among the known structures. A phosphate ion was localized in the active site of the enzyme. The binding of the surface loop to the active centre is stabilized by the phosphate ion, which correlates with the observed aggregation of TBN1 in phosphate buffer. The conserved binding of the surface loop to the active centre suggests biological relevance of the contact in a regulatory function or in the formation of oligomers.

SUBMITTER: Stransky J

PROVIDER: S-EPMC4631591 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Phosphate binding in the active centre of tomato multifunctional nuclease TBN1 and analysis of superhelix formation by the enzyme.

Stránský Jan J Koval' Tomáš T Podzimek Tomáš T Týcová Anna A Lipovová Petra P Matoušek Jaroslav J Kolenko Petr P Fejfarová Karla K Dušková Jarmila J Skálová Tereza T Hašek Jindřich J Dohnálek Jan J

Acta crystallographica. Section F, Structural biology communications 20151023 Pt 11

Tomato multifunctional nuclease TBN1 belongs to the type I nuclease family, which plays an important role in apoptotic processes and cell senescence in plants. The newly solved structure of the N211D mutant is reported. Although the main crystal-packing motif (the formation of superhelices) is conserved, the details differ among the known structures. A phosphate ion was localized in the active site of the enzyme. The binding of the surface loop to the active centre is stabilized by the phosphate ...[more]

PMID: 26527269

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Dataset Information

Phosphate binding in the active centre of tomato multifunctional nuclease TBN1 and analysis of superhelix formation by the enzyme.

Publications

Phosphate binding in the active centre of tomato multifunctional nuclease TBN1 and analysis of superhelix formation by the enzyme.

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