Abstract
The crystal structure of the met repressor-operator complex shows two dimeric repressor molecules bound to adjacent sites 8 base pairs apart on an 18-base-pair DNA fragment. Sequence specificity is achieved by insertion of double-stranded antiparallel protein beta-ribbons into the major groove of B-form DNA, with direct hydrogen-bonding between amino-acid side chains and the base pairs. The repressor also recognizes sequence-dependent distortion or flexibility of the operator phosphate backbone, conferring specificity even for inaccessible base pairs.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Bacterial Proteins / chemistry*
-
Bacterial Proteins / metabolism*
-
Base Sequence
-
Crystallography*
-
DNA, Bacterial / chemistry
-
Escherichia coli / genetics
-
Escherichia coli Proteins*
-
Gene Expression Regulation, Bacterial / physiology*
-
Genes, Regulator*
-
Methionine / biosynthesis*
-
Molecular Conformation
-
Molecular Sequence Data
-
Operator Regions, Genetic / genetics*
-
Repressor Proteins / chemistry*
-
Repressor Proteins / metabolism*
Substances
-
Bacterial Proteins
-
DNA, Bacterial
-
Escherichia coli Proteins
-
Repressor Proteins
-
methionine repressor protein, Bacteria
-
methionine repressor protein, E coli
-
Methionine