Abstract
Operator DNA fragments were modified in the presence of lac repressor protein or its trypsin-resistant core. Operator DNA was alkylated or cleaved enzymatically with these related proteins present to compare the influences of their binding on the reactivities or enzymatic susceptibilities of individual bases in the sequence. These two protein species have pronounced and distinguishable effects on the reactivity of the bases of the operator fragment toward methylation by dimethyl sulfate. Perturbation of base alkylation by the trypsin-resistant core repressor is most pronounced in the inner, asymmetric region of the operator DNA, while repressor effects extend further on either end of the operator sequence. Digestion of the two protein-operator complexes by DNase I yields fragment patterns that differ primarily in extent of protection. These data extend the experimental base supporting the involvement of the core region of the lac repressor in addition to its NH2 termini in the operator-specific binding activity of this protein.
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- Alexander M. E., Burgum A. A., Noall R. A., Shaw M. D., Matthews K. S. Modification of tyrosine residues of the lactose repressor protein. Biochim Biophys Acta. 1977 Aug 23;493(2):367–379. doi: 10.1016/0005-2795(77)90193-3. [DOI] [PubMed] [Google Scholar]
- Arndt K., Nick H., Boschelli F., Lu P., Sadler J. Repressor--operator interaction in the lac operon. III. Nuclear magnetic resonance observations with altered amino-terminal DNA binding domains. J Mol Biol. 1982 Nov 5;161(3):439–457. doi: 10.1016/0022-2836(82)90248-0. [DOI] [PubMed] [Google Scholar]
- Bennett G. N. Formation of alkali labile linkages in DNA by hedamycin and use of hedamycin as a probe of protein-DNA complexes. Nucleic Acids Res. 1982 Aug 11;10(15):4581–4594. doi: 10.1093/nar/10.15.4581. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Boschelli F., Jarema M. A., Lu P. Inducer and anti-inducer interactions with the lac repressor seen by nuclear magnetic resonance changes at tyrosines and tryptophans. J Biol Chem. 1981 Nov 25;256(22):11595–11599. [PubMed] [Google Scholar]
- Burgum A. A., Matthews K. S. Lactose repressor protein modified with fluorescein mercuric acetate. J Biol Chem. 1978 Jun 25;253(12):4279–4286. [PubMed] [Google Scholar]
- Butler A. P., Revzin A., von Hippel P. H. Molecular parameters characterizing the interaction of Escherichia coli lac repressor with non-operator DNA and inducer. Biochemistry. 1977 Nov 1;16(22):4757–4768. doi: 10.1021/bi00641a001. [DOI] [PubMed] [Google Scholar]
- Dunaway M., Manly S. P., Matthews K. S. Model for lactose repressor protein and its interaction with ligands. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7181–7185. doi: 10.1073/pnas.77.12.7181. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Files J. G., Weber K. Limited proteolytic digestion of lac repressor by trypsin. Chemical nature of the resulting trypsin-resistant core. J Biol Chem. 1976 Jun 10;251(11):3386–3391. [PubMed] [Google Scholar]
- Friedman B. E., Olson J. S., Matthews K. S. Interaction of lac repressor with inducer, kinetic and equilibrium measurements. J Mol Biol. 1977 Mar 25;111(1):27–39. doi: 10.1016/s0022-2836(77)80129-0. [DOI] [PubMed] [Google Scholar]
- Geisler N., Weber K. Isolation of amino-terminal fragment of lactose repressor necessary for DNA binding. Biochemistry. 1977 Mar 8;16(5):938–943. doi: 10.1021/bi00624a020. [DOI] [PubMed] [Google Scholar]
- Jacobs J. W., Niall H. D., Sharp G. W. The amino terminal sequence of cholera toxin subunits. Biochem Biophys Res Commun. 1974 Nov 27;61(2):391–395. doi: 10.1016/0006-291x(74)90969-3. [DOI] [PubMed] [Google Scholar]
- Jovin T. M., Geisler N., Weber K. Amino-terminal fragments of Escherichia coli lac repressor bind to DNA. Nature. 1977 Oct 20;269(5630):668–672. doi: 10.1038/269668a0. [DOI] [PubMed] [Google Scholar]
- Lin S., Riggs A. D. A comparison of lac repressor binding to operator and to nonoperator DNA. Biochem Biophys Res Commun. 1975 Feb 3;62(3):704–710. doi: 10.1016/0006-291x(75)90456-8. [DOI] [PubMed] [Google Scholar]
- Lin S., Riggs A. D. The general affinity of lac repressor for E. coli DNA: implications for gene regulation in procaryotes and eucaryotes. Cell. 1975 Feb;4(2):107–111. doi: 10.1016/0092-8674(75)90116-6. [DOI] [PubMed] [Google Scholar]
- Manly S. P., Matthews K. S. Activity changes in lac repressor with cysteine oxidation. J Biol Chem. 1979 May 10;254(9):3341–3347. [PubMed] [Google Scholar]
- Matthews K. S. Tryptic core protein of lactose repressor binds operator DNA. J Biol Chem. 1979 May 10;254(9):3348–3353. [PubMed] [Google Scholar]
- Matthews K. S. Ultraviolet difference spectra of the lactose repressor protein. II. Trypsin core protein. Biochim Biophys Acta. 1974 Aug 8;359(2):334–340. doi: 10.1016/0005-2795(74)90232-3. [DOI] [PubMed] [Google Scholar]
- Maxam A. M., Gilbert W. Sequencing end-labeled DNA with base-specific chemical cleavages. Methods Enzymol. 1980;65(1):499–560. doi: 10.1016/s0076-6879(80)65059-9. [DOI] [PubMed] [Google Scholar]
- Miller J. H., Ganem D., Lu P., Schmitz A. Genetic studies of the lac repressor. I. Correlation of mutational sites with specific amino acid residues: construction of a colinear gene-protein map. J Mol Biol. 1977 Jan 15;109(2):275–298. doi: 10.1016/s0022-2836(77)80034-x. [DOI] [PubMed] [Google Scholar]
- Miller J. H. Genetic studies of the lac repressor. XI. On aspects of lac repressor structure suggested by genetic experiments. J Mol Biol. 1979 Jun 25;131(2):249–258. doi: 10.1016/0022-2836(79)90075-5. [DOI] [PubMed] [Google Scholar]
- Miller J. H., Schmeissner U. Genetic studies of the lac repressor. X. Analysis of missense mutations in the lacI gene. J Mol Biol. 1979 Jun 25;131(2):223–248. doi: 10.1016/0022-2836(79)90074-3. [DOI] [PubMed] [Google Scholar]
- Müller-Hill B. Lac repressor and lac operator. Prog Biophys Mol Biol. 1975;30(2-3):227–252. doi: 10.1016/0079-6107(76)90011-0. [DOI] [PubMed] [Google Scholar]
- Nick H., Arndt K., Boschelli F., Jarema M. A., Lillis M., Sadler J., Caruthers M., Lu P. lac repressor-lac operator interaction: NMR observations. Proc Natl Acad Sci U S A. 1982 Jan;79(2):218–222. doi: 10.1073/pnas.79.2.218. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nick H., Arndt K., Boschelli F., Jarema M. A., Lillis M., Sommer H., Lu P., Sadler J. Repressor--operator interaction in the lac operon. II. Observations at the tyrosines and tryptophans. J Mol Biol. 1982 Nov 5;161(3):417–438. doi: 10.1016/0022-2836(82)90247-9. [DOI] [PubMed] [Google Scholar]
- O'Gorman R. B., Matthews K. S. N-Bromosuccinimide modification of Lac repressor protein. J Biol Chem. 1977 Jun 10;252(11):3565–3571. [PubMed] [Google Scholar]
- Ogata R. T., Gilbert W. An amino-terminal fragment of lac repressor binds specifically to lac operator. Proc Natl Acad Sci U S A. 1978 Dec;75(12):5851–5854. doi: 10.1073/pnas.75.12.5851. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ogata R. T., Gilbert W. DNA-binding site of lac repressor probed by dimethylsulfate methylation of lac operator. J Mol Biol. 1979 Aug 25;132(4):709–728. doi: 10.1016/0022-2836(79)90384-x. [DOI] [PubMed] [Google Scholar]
- Pfahl M. Genetic map of the lactose repressor gene (i) of Escherichia coli. Genetics. 1972 Nov;72(3):393–410. doi: 10.1093/genetics/72.3.393. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pfahl M., Stockter C., Gronenborn B. Genetic analysis of the active sites of lac repressor. Genetics. 1974 Apr;76(4):669–679. doi: 10.1093/genetics/76.4.669. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Platt T., Files J. G., Weber K. Lac repressor. Specific proteolytic destruction of the NH 2 -terminal region and loss of the deoxyribonucleic acid-binding activity. J Biol Chem. 1973 Jan 10;248(1):110–121. [PubMed] [Google Scholar]
- Rosenberg J. M., Khallai O. B., Kopka M. L., Dickerson R. E., Riggs A. D. Lac repressor purification without inactivation of DNA binding activity. Nucleic Acids Res. 1977 Mar;4(3):567–572. doi: 10.1093/nar/4.3.567. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schmitz A., Galas D. J. Sequence-specific interactions of the tight-binding I12-X86 lac repressor with non-operator DNA. Nucleic Acids Res. 1980 Feb 11;8(3):487–506. doi: 10.1093/nar/8.3.487. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schnarr M., Maurizot J. C. Unfolding of lac repressor and its proteolytic fragment by urea: headpieces stabilize the core within lac repressor. Biochemistry. 1981 Oct 13;20(21):6164–6169. doi: 10.1021/bi00524a039. [DOI] [PubMed] [Google Scholar]
- Yang D. S., Burgum A. A., Matthews K. S. Modification of the cysteine residues of the lactose repressor protein using chromophoric probes. Biochim Biophys Acta. 1977 Jul 22;493(1):24–36. doi: 10.1016/0005-2795(77)90257-4. [DOI] [PubMed] [Google Scholar]


