title: Evolution of sequence specificity in a restriction endonuclease by a point mutation.
abstract: Restriction endonucleases (REases) protect bacteria from invading foreign DNAs and are endowed with exquisite sequence specificity. REases have originated from the ancestral proteins and evolved new sequence specificities by genetic recombination, gene duplication, replication slippage, and transpositional events. They are also speculated to have evolved from nonspecific endonucleases, attaining a high degree of sequence specificity through point mutations. We describe here an example of generation of exquisitely site-specific REase from a highly-promiscuous one by a single point mutation.
authors.affiliation: Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
authors.forename: Matheshwaran
authors.initials: M
authors.lastname: Saravanan
authors.forename: Kommireddy
authors.initials: K
authors.lastname: Vasu
authors.forename: Valakunja
authors.initials: V
authors.lastname: Nagaraja
mesh_terms: D001665:Binding Sites; D004247:DNA / Q000737:chemistry; D004262:DNA Restriction Enzymes / Q000235:genetics*; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics* / Q000378:metabolism; D007477:Ions; D007700:Kinetics; D008274:Magnesium / Q000737:chemistry; D008670:Metals / Q000737:chemistry; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D010957:Plasmids / Q000378:metabolism; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic
chemical_list: D007477:Ions; D008670:Metals; D004247:DNA; D004262:DNA Restriction Enzymes; D015252:Deoxyribonucleases, Type II Site-Specific; C029312:GGTACC-specific type II deoxyribonucleases; D008274:Magnesium