Differential inactivation of mammalian and Escherichia coli O6-alkylguanine-DNA alkyltransferases by O6-benzylguanine.

2.50
Hdl Handle:
http://hdl.handle.net/10541/96178
Title:
Differential inactivation of mammalian and Escherichia coli O6-alkylguanine-DNA alkyltransferases by O6-benzylguanine.
Authors:
Elder, Rhoderick H; Margison, Geoffrey P; Rafferty, Joseph A
Abstract:
The action of O6-benzylguanine (O6-BzlG) on recombinant mammalian and Escherichia coli O6-alkylguanine-DNA alkyltransferases (ATase; EC 2.1.1.63; methylated-DNA-protein-cysteine methyltransferase) was compared by preincubation of these proteins with the base, followed by measurement of residual ATase activity using [3H]methylated substrate DNA. All of the mammalian proteins examined were inactivated by O6-BzlG (Chinese hamster: I40, 0.04 microM; human and rat: I40, 0.06 microM); however, the murine ATase was substantially more resistant requiring 4-5 fold higher concentrations of O6-BzlG to achieve the same levels of inactivation (I40, 0.28 microM). A similar differential inactivation was seen with human and murine ATases when extracts of 3T6 (murine) cells and Raji (human) cells were compared. Of the two E. coli ATase proteins, only the ogt-encoded protein was inactivated, but approximately 400 times more O6-BzlG was required to achieve a level of inactivation similar to that seen with the human protein (I40, 24.8 microM). When O6-BzlG was present in an oligonucleotide, the differential effect on the murine, human and ogt-encoded ATases was not seen and only the ada-encoded ATase remained refractory under the conditions used.
Affiliation:
CRC Department of Carcinogenesis, Paterson Institute for Cancer Research, Christie Hospital (NHS) Trust, Manchester, U.K.
Citation:
Differential inactivation of mammalian and Escherichia coli O6-alkylguanine-DNA alkyltransferases by O6-benzylguanine. 1994, 298 ( Pt 1):231-5 Biochem. J.
Journal:
The Biochemical Journal
Issue Date:
15-Feb-1994
URI:
http://hdl.handle.net/10541/96178
PubMed ID:
8129725
Type:
Article
Language:
en
ISSN:
0264-6021
Appears in Collections:
All Paterson Institute for Cancer Research

Full metadata record

DC FieldValue Language
dc.contributor.authorElder, Rhoderick Hen
dc.contributor.authorMargison, Geoffrey Pen
dc.contributor.authorRafferty, Joseph Aen
dc.date.accessioned2010-04-09T13:40:09Z-
dc.date.available2010-04-09T13:40:09Z-
dc.date.issued1994-02-15-
dc.identifier.citationDifferential inactivation of mammalian and Escherichia coli O6-alkylguanine-DNA alkyltransferases by O6-benzylguanine. 1994, 298 ( Pt 1):231-5 Biochem. J.en
dc.identifier.issn0264-6021-
dc.identifier.pmid8129725-
dc.identifier.urihttp://hdl.handle.net/10541/96178-
dc.description.abstractThe action of O6-benzylguanine (O6-BzlG) on recombinant mammalian and Escherichia coli O6-alkylguanine-DNA alkyltransferases (ATase; EC 2.1.1.63; methylated-DNA-protein-cysteine methyltransferase) was compared by preincubation of these proteins with the base, followed by measurement of residual ATase activity using [3H]methylated substrate DNA. All of the mammalian proteins examined were inactivated by O6-BzlG (Chinese hamster: I40, 0.04 microM; human and rat: I40, 0.06 microM); however, the murine ATase was substantially more resistant requiring 4-5 fold higher concentrations of O6-BzlG to achieve the same levels of inactivation (I40, 0.28 microM). A similar differential inactivation was seen with human and murine ATases when extracts of 3T6 (murine) cells and Raji (human) cells were compared. Of the two E. coli ATase proteins, only the ogt-encoded protein was inactivated, but approximately 400 times more O6-BzlG was required to achieve a level of inactivation similar to that seen with the human protein (I40, 24.8 microM). When O6-BzlG was present in an oligonucleotide, the differential effect on the murine, human and ogt-encoded ATases was not seen and only the ada-encoded ATase remained refractory under the conditions used.en
dc.language.isoenen
dc.subject.meshAnimals-
dc.subject.meshBase Sequence-
dc.subject.meshCells, Cultured-
dc.subject.meshCricetinae-
dc.subject.meshCricetulus-
dc.subject.meshEscherichia coli-
dc.subject.meshGuanine-
dc.subject.meshHumans-
dc.subject.meshMethyltransferases-
dc.subject.meshMice-
dc.subject.meshMolecular Sequence Data-
dc.subject.meshO(6)-Methylguanine-DNA Methyltransferase-
dc.subject.meshOligodeoxyribonucleotides-
dc.subject.meshRats-
dc.titleDifferential inactivation of mammalian and Escherichia coli O6-alkylguanine-DNA alkyltransferases by O6-benzylguanine.en
dc.typeArticleen
dc.contributor.departmentCRC Department of Carcinogenesis, Paterson Institute for Cancer Research, Christie Hospital (NHS) Trust, Manchester, U.K.en
dc.identifier.journalThe Biochemical Journalen
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