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The two common polymorphic forms of human NRH-quinone oxidoreductase 2 (NQO2) have different biochemical properties.

ABSTRACT: There are two common forms of NRH-quinone oxidoreductase 2 (NQO2) in the human population resulting from SNP rs1143684. One has phenylalanine at position 47 (NQO2-F47) and the other leucine (NQO2-L47). Using recombinant proteins, we show that these variants have similar steady state kinetic parameters, although NQO2-L47 has a slightly lower specificity constant. NQO2-L47 is less stable towards proteolytic digestion and thermal denaturation than NQO2-F47. Both forms are inhibited by resveratrol, but NQO2-F47 shows negative cooperativity with this inhibitor. Thus these data demonstrate, for the first time, clear biochemical differences between the variants which help explain previous biomedical and epidemiological findings.

SUBMITTER: Megarity CF

PROVIDER: S-EPMC4045209 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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The two common polymorphic forms of human NRH-quinone oxidoreductase 2 (NQO2) have different biochemical properties.

Megarity Clare F CF Gill James R E JR Caraher M Clare MC Stratford Ian J IJ Nolan Karen A KA Timson David J DJ

FEBS letters 20140312 9

There are two common forms of NRH-quinone oxidoreductase 2 (NQO2) in the human population resulting from SNP rs1143684. One has phenylalanine at position 47 (NQO2-F47) and the other leucine (NQO2-L47). Using recombinant proteins, we show that these variants have similar steady state kinetic parameters, although NQO2-L47 has a slightly lower specificity constant. NQO2-L47 is less stable towards proteolytic digestion and thermal denaturation than NQO2-F47. Both forms are inhibited by resveratrol, ...[more]

PMID: 24631540

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