EcoRI
| EcoRI | ||
|---|---|---|
|
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| Ribbon model with DNA according to PDB 1QPS | ||
|
Existing structural data : 1ckq , 1cl8 , 1eri , 1qc9 , 1qps , 1qrh , 1qri , 2oxv |
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| Mass / length primary structure | 276 amino acids | |
| Secondary to quaternary structure | Homodimer | |
| Cofactor | 2 mg 2+ | |
| Identifier | ||
| External IDs | ||
| Enzyme classification | ||
| EC, category | 3.1.21.4 , restriction enzyme | |
| Response type | hydrolysis | |
| Substrate | GAATTC (dDNA) | |
| Occurrence | ||
| Homology family | ECOR1 | |
| Parent taxon | Proteobacteria | |
EcoRI is an enzyme from the nuclease family . It was the first nuclease I from strain R of E scherichia co li . It is used especially in molecular biology as a restriction enzyme . The enzyme consists of a homodimer and cuts double-stranded DNA within the palindromic recognition sequence to form a 5 'overhang as follows:
| Recognition sequence | Restriction cut |
|---|---|
5'-GAATTC-3' 3'-CTTAAG-5' |
5'-G AATTC-3' 3'-CTTAA G-5' |
This formation of a 4-base overhang (“sticky ends”) is used in molecular biology to facilitate the ligation of DNA fragments. Under certain conditions, EcoRI shows a reduced selectivity for the recognition sequence ( star activity ).