2jhn
From Proteopedia
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==Overview== | ==Overview== | ||
| - | N(1)-methyladenine (m(1)A) and N(3)-methylcytosine (m(3)C) are major toxic, and mutagenic lesions induced by alkylation in single-stranded DNA. In, bacteria and mammals, m(1)A and m(3)C were recently shown to be repaired, by AlkB-mediated oxidative demethylation, a direct DNA damage reversal, mechanism. No AlkB gene homologues have been identified in Archaea. We, report that m(1)A and m(3)C are repaired by the AfAlkA base excision, repair glycosylase of Archaeoglobus fulgidus, suggesting a different, repair mechanism for these lesions in the third domain of life. In, addition, AfAlkA was found to effect a robust excision of, 1,N(6)-ethenoadenine. We present a high-resolution crystal structure of, AfAlkA, which, together with the characterization of several site-directed, mutants, forms a . | + | N(1)-methyladenine (m(1)A) and N(3)-methylcytosine (m(3)C) are major toxic, and mutagenic lesions induced by alkylation in single-stranded DNA. In, bacteria and mammals, m(1)A and m(3)C were recently shown to be repaired, by AlkB-mediated oxidative demethylation, a direct DNA damage reversal, mechanism. No AlkB gene homologues have been identified in Archaea. We, report that m(1)A and m(3)C are repaired by the AfAlkA base excision, repair glycosylase of Archaeoglobus fulgidus, suggesting a different, repair mechanism for these lesions in the third domain of life. In, addition, AfAlkA was found to effect a robust excision of, 1,N(6)-ethenoadenine. We present a high-resolution crystal structure of, AfAlkA, which, together with the characterization of several site-directed, mutants, forms a molecular rationalization for the newly discovered base, excision activity. |
==About this Structure== | ==About this Structure== | ||
| - | 2JHN is a | + | 2JHN is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Archaeoglobus_fulgidus Archaeoglobus fulgidus] with HG, NA, MBO, MES and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA-3-methyladenine_glycosylase_II DNA-3-methyladenine glycosylase II], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.21 3.2.2.21] Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2JHN OCA]. |
==Reference== | ==Reference== | ||
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[[Category: n3-methylcytosine]] | [[Category: n3-methylcytosine]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 14:27:44 2007'' |
Revision as of 12:22, 5 November 2007
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3-METHYLADENINE DNA-GLYCOSYLASE FROM ARCHAEOGLOBUS FULGIDUS
Overview
N(1)-methyladenine (m(1)A) and N(3)-methylcytosine (m(3)C) are major toxic, and mutagenic lesions induced by alkylation in single-stranded DNA. In, bacteria and mammals, m(1)A and m(3)C were recently shown to be repaired, by AlkB-mediated oxidative demethylation, a direct DNA damage reversal, mechanism. No AlkB gene homologues have been identified in Archaea. We, report that m(1)A and m(3)C are repaired by the AfAlkA base excision, repair glycosylase of Archaeoglobus fulgidus, suggesting a different, repair mechanism for these lesions in the third domain of life. In, addition, AfAlkA was found to effect a robust excision of, 1,N(6)-ethenoadenine. We present a high-resolution crystal structure of, AfAlkA, which, together with the characterization of several site-directed, mutants, forms a molecular rationalization for the newly discovered base, excision activity.
About this Structure
2JHN is a Single protein structure of sequence from Archaeoglobus fulgidus with HG, NA, MBO, MES and GOL as ligands. Active as DNA-3-methyladenine glycosylase II, with EC number 3.2.2.21 Structure known Active Site: AC1. Full crystallographic information is available from OCA.
Reference
Structural basis for enzymatic excision of N1-methyladenine and N3-methylcytosine from DNA., Leiros I, Nabong MP, Grosvik K, Ringvoll J, Haugland GT, Uldal L, Reite K, Olsbu IK, Knaevelsrud I, Moe E, Andersen OA, Birkeland NK, Ruoff P, Klungland A, Bjelland S, EMBO J. 2007 Apr 18;26(8):2206-17. Epub 2007 Mar 29. PMID:17396151
Page seeded by OCA on Mon Nov 5 14:27:44 2007
Categories: Archaeoglobus fulgidus | DNA-3-methyladenine glycosylase II | Single protein | Andersen, O.A. | Birkeland, N.K. | Bjelland, S. | Grosvik, K. | Haugland, G.T. | Klungland, A. | Knaevelsrud, I. | Leiros, I. | Moe, E. | Nabong, M.P. | Olsbu, I.K. | Reite, K. | Ringvoll, J. | Ruoff, P. | Uldal, L. | GOL | HG | MBO | MES | NA | Alka | Dna repair | Hydrolase | Hyperthermophiles | N1-methyladenine | N3-methylcytosine
