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Inactivation of NEIL2 DNA glycosylase by pyridoxal phosphate reveals a loop important for substrate binding.

ABSTRACT: Pyridoxal-5'-phosphate (PLP), in addition to its known metabolic functions, inactivates many DNA-dependent enzymes through conjugation to their critical amino groups. We have investigated the ability of PLP to inhibit bifunctional DNA repair glycosylases, which possess a catalytic amine. Of six enzymes tested, only endonuclease VIII-like protein 2 (NEIL2) was significantly inhibited by PLP. The inhibition was due to Schiff base formation between PLP and the enzyme. PLP-conjugated NEIL2 completely lost its ability to bind damaged DNA. Liquid chromatography/nanoelectrospray ionization tandem mass spectrometry of the products of proteolysis of pyridoxylated NEIL2 identified Lys50 as the site of modification. Thus, the beta2/beta3 loop where Lys50 is located in NEIL2 is important for DNA binding, presumably lies next to a phosphate-binding site, and may represent a target for regulation of the enzyme activity.

SUBMITTER: Grin IR

PROVIDER: S-EPMC2857644 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Inactivation of NEIL2 DNA glycosylase by pyridoxal phosphate reveals a loop important for substrate binding.

Grin Inga R IR Rieger Robert A RA Zharkov Dmitry O DO

Biochemical and biophysical research communications 20100220 1

Pyridoxal-5'-phosphate (PLP), in addition to its known metabolic functions, inactivates many DNA-dependent enzymes through conjugation to their critical amino groups. We have investigated the ability of PLP to inhibit bifunctional DNA repair glycosylases, which possess a catalytic amine. Of six enzymes tested, only endonuclease VIII-like protein 2 (NEIL2) was significantly inhibited by PLP. The inhibition was due to Schiff base formation between PLP and the enzyme. PLP-conjugated NEIL2 completel ...[more]

PMID: 20175991

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Inactivation of NEIL2 DNA glycosylase by pyridoxal phosphate reveals a loop important for substrate binding.

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Inactivation of NEIL2 DNA glycosylase by pyridoxal phosphate reveals a loop important for substrate binding.

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