Mapping of the priming substrate contacts in the active center of Escherichia coli RNA polymerase.
The active center of DNA-dependent RNA polymerase performs the principal biochemical reaction of gene expression. Using cross-linkable substrate analogs and site-directed mutations, two evolutionarily invariant amino acids in the beta subunit of the Escherichia coli enzyme (Lys1065 and His1237) were mapped close to the binding site of the priming substrate of the reaction. Surprisingly, the mutational substitution of these residues (Lys1065----Arg and His1237----Ala) did not inactivate the catalytic function, but inhibited transition from the initiation to the elongation stage of transcription.
Mustaev
A
A
Institute of Molecular Genetics, Union of Soviet Socialist Republics Academy of Sciences, Moscow.
Kashlev
M
M
Lee
J Y
JY
Polyakov
A
A
Lebedev
A
A
Zalenskaya
K
K
Grachev
M
M
Goldfarb
A
A
Nikiforov
V
V
D000345:Affinity Labels; D000595:Amino Acid Sequence; D001665:Binding Sites; D005075:Biological Evolution; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011994:Recombinant Proteins / Q000378:metabolism
D000345:Affinity Labels; D046911:Macromolecular Substances; D011994:Recombinant Proteins; D012321:DNA-Directed RNA Polymerases