Radiation-induced tetramer-to-dimer transition of Escherichia coli lactose repressor

Journal Article · Fri Aug 21 00:00:00 EDT 2009 · Biochemical and Biophysical Research Communications

DOI:https://doi.org/10.1016/J.BBRC.2009.06.012· OSTI ID:22199767

Goffinont, S. ^[1]; Davidkova, M. ^[2]

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1. Centre de Biophysique Moleculaire, CNRS, rue C. Sadron, 45071 Orleans (France)
2. Department of Radiation Dosimetry, Nuclear Physics Institute AS CR, Na Truhlarce 39/64, 18086, Prague 8 (Czech Republic)

The wild type lactose repressor of Escherichia coli is a tetrameric protein formed by two identical dimers. They are associated via a C-terminal 4-helix bundle (called tetramerization domain) whose stability is ensured by the interaction of leucine zipper motifs. Upon in vitro {gamma}-irradiation the repressor losses its ability to bind the operator DNA sequence due to damage of its DNA-binding domains. Using an engineered dimeric repressor for comparison, we show here that irradiation induces also the change of repressor oligomerisation state from tetramer to dimer. The splitting of the tetramer into dimers can result from the oxidation of the leucine residues of the tetramerization domain.

• OSTI ID: 22199767
• Journal Information: Biochemical and Biophysical Research Communications, Vol. 386, Issue 2; Other Information: Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0006-291X
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRONMENTAL POLLUTANT EFFECTS ON LIVING ORGANISMS AND BIOLOGICAL MATERIALS
BIOLOGICAL RADIATION EFFECTS
DIMERS
DNA
ESCHERICHIA COLI
GAMMA RADIATION
IN VITRO
IRRADIATION
LACTOSE
LEUCINE
OXIDATION
PROTEINS