Characterisation of multiple substrate-specific (d)ITP/(d)XTPase and modelling of deaminated purine nucleotide metabolism
Accumulation of modified nucleotides is defective to variouscellular processes, especially those involving DNA and RNA.To be viable, organisms possess a number of (deoxy)nucleotidephosphohydrolases, which hydrolyze these nucleotidesremoving them from the active NTP and dNTP pools.Deamination of puri...
Main Authors: | , , , |
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Format: | Article |
Language: | English |
Published: |
Korean Society for Biochemistry and Molecular Biology
2012-04-01
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Series: | BMB Reports |
Subjects: | |
Online Access: | http://bmbreports.org/jbmb/pdf.php?data=MTMxMTA4MTZAcGRmX3JhaW50cmFjZV9sZWV5c0AlNUI0NS00JTVEMTIwNDI2MTkxN18lMjgyNTktMjY0JTI5Qk1CXzExLTE2OS5wZGY= |
Summary: | Accumulation of modified nucleotides is defective to variouscellular processes, especially those involving DNA and RNA.To be viable, organisms possess a number of (deoxy)nucleotidephosphohydrolases, which hydrolyze these nucleotidesremoving them from the active NTP and dNTP pools.Deamination of purine bases can result in accumulation ofsuch nucleotides as ITP, dITP, XTP and dXTP. E. coli RdgB hasbeen characterised as a deoxyribonucleoside triphosphate pyrophosphohydrolasethat can act on these nucleotides. S. cerevisiaehomologue encoded by YJR069C was purified and its(d)NTPase activity was assayed using fifteen nucleotidesubstrates. ITP, dITP, and XTP were identified as major substratesand kinetic parameters measured. Inhibition by ATP,dATP and GTP were established. On the basis of experimentaland published data, modelling and simulation of ITP, dITP,XTP and dXTP metabolism was performed. (d)ITP/(d)XTPase isa new example of enzyme with multiple substrate-specificitydemonstrating that multispecificity is not a rare phenomenon[BMB reports 2012; 45(4): 259-264] |
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ISSN: | 1976-6696 1976-670X |