4 publications

4 publications

Chemical Conversion of a DNA-Binding Protein into a Site-Specific Nuclease

Sigman, D.S.

Science 1987, 237, 1197-1201, 10.1126/science.2820056

The tryptophan gene (trp) repressor of Escherichia coli has been converted into a site-specific nuclease by covalently attaching it to the 1,10-phenanthroline-copper complex. In its cuprous form, the coordination complex with hydrogen peroxide as a coreactant cleaves DNA by oxidatively attacking the deoxyribose moiety. The chemistry for the attachment of 1,10-phenanthroline to the trp repressor involves modification of lysyl residues with iminothiolane followed by alkylation of the resulting sulfhydryl groups with 5-iodoacetamido-1,10-phenanthroline. The modified trp repressor cleaves the operators of aroH and trpEDCBA upon the addition of cupric ion and thiol in a reaction dependent on the corepressor L-tryptophan. Scission was restricted to the binding site for the repressor, defined by deoxyribonuclease I footprinting. Since DNA-binding proteins have recognition sequences approximately 20 base pairs long, the nucleolytic activities derived from them could be used to isolate long DNA fragments for sequencing or chromosomal mapping.


Metal: Cu
Ligand type: Phenanthroline
Anchoring strategy: Covalent
Optimization: ---
Reaction: Oxidative cleavage
Max TON: <1
ee: ---
PDB: ---
Notes: Engineered sequence specificity

Flavohemoglobin: A Semisynthetic Hydroxylase Acting in the Absence of Reductase

Kaiser, E.T.

J. Am. Chem. Soc. 1987, 109, 606-607, 10.1021/ja00236a062

n/a


Metal: Fe
Ligand type: Porphyrin
Host protein: Hemoglobin
Anchoring strategy: ---
Optimization: ---
Max TON: ---
ee: ---
PDB: ---
Notes: ---

Generation of a Hybrid Sequence-Specific Single Stranded Deoxyribonuclease

Schultz, P.G.

Science 1987, 238, 1401-1403, 10.1126/science.3685986

The relatively nonspecific single-stranded deoxyribonuclease, staphylococcal nuclease, was selectively fused to an oligonucleotide binding site of defined sequence to generate a hybrid enzyme. A cysteine was substituted for Lys116 in the enzyme by oligonucleotide-directed mutagenesis and coupled to an oligonucleotide that contained a 3'-thiol. The resulting hybrid enzyme cleaved single-stranded DNA at sites adjacent to the oligonucleotide binding site.


Metal: Ca
Ligand type: Undefined
Host protein: Staphylococcal nuclease
Anchoring strategy: ---
Optimization: ---
Max TON: <1
ee: ---
PDB: ---
Notes: Engineered sequence specificity

Synthesis of a Sequence-Specific DNA-Cleaving Peptide

Dervan, P.B.

Science 1987, 238, 1129-1132, 10.1126/science.3120311

A synthetic 52-residue peptide based on the sequence-specific DNA-binding domain of Hin recombinase (139-190) has been equipped with ethylenediaminetetraacetic acid (EDTA) at the amino terminus. In the presence of Fe(II), this synthetic EDTA-peptide cleaves DNA at Hin recombination sites. The cleavage data reveal that the amino terminus of Hin(139-190) is bound in the minor groove of DNA near the symmetry axis of Hin recombination sites. This work demonstrates the construction of a hybrid peptide combining two functional domains: sequence-specific DNA binding and DNA cleavage.


Metal: Fe
Ligand type: EDTA
Anchoring strategy: Covalent
Optimization: ---
Reaction: DNA cleavage
Max TON: <1
ee: ---
PDB: ---
Notes: Engineered sequence specificity