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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.

SUBMITTER: Saravanan M

PROVIDER: S-EPMC2492507 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Evolution of sequence specificity in a restriction endonuclease by a point mutation.

Saravanan Matheshwaran M Vasu Kommireddy K Nagaraja Valakunja V

Proceedings of the National Academy of Sciences of the United States of America 20080722 30

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 generat ...[more]

PMID: 18647833

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