Exonuclease VII
| Exonuclease VII, large subunit | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| Symbol | Exonuc_VII_L | ||||||||
| Pfam | PF02601 | ||||||||
| InterPro | IPR020579 | ||||||||
| |||||||||
| Exonuclease VII small subunit | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| crystal structure of exodeoxyribonuclease vii small subunit (np_881400.1) from bordetella pertussis at 2.40 a resolution | |||||||||
| Identifiers | |||||||||
| Symbol | Exonuc_VII_S | ||||||||
| Pfam | PF02609 | ||||||||
| InterPro | IPR003761 | ||||||||
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The enzyme exodeoxyribonuclease VII (EC 3.1.11.6, Escherichia coli exonuclease VII, E. coli exonuclease VII, endodeoxyribonuclease VII, exodeoxyribonuclease VII) is a bacterial exonuclease enzyme.[1] [2] It is composed of two nonidentical subunits; one large subunit and 4 small ones.[3] that catalyses exonucleolytic cleavage in either 5′- to 3′- or 3′- to 5′-direction to yield nucleoside 5′-phosphates. The large subunit also contains an N-terminal OB-fold domain that binds to nucleic acids.
The widely used quinolone antibiotics induce DNA damage in bacterial cells by trapping DNA gyrase (an essential type II topoisomerase), leading to blocked gyrase cleavage complexes.[4] Exonuclease VII participates in repairing such DNA damage by resolving the trapped cleavage complexes.[4]
When Escherichia coli bacteria recA mutants are UV-irradiated, "reckless" DNA degradation occurs that involves exonuclease VII.[5]
References
[edit ]- ^ Chase, J.W.; Richardson, C.C. (1974). "Ribonuclease VII of Escherichia coli". J. Biol. Chem. 249 (14): 4545–4552. doi:10.1016/S0021-9258(19)42453-8 . PMID 4602029.
- ^ Chase, J.W.; Richardson, C.C. (1974). "Exonuclease VII of Escherichia coli". J. Biol. Chem. 249 (14): 4553–4561. doi:10.1016/S0021-9258(19)42454-X . PMID 4602030.
- ^ Vales LD, Rabin BA, Chase JW (August 1982). "Subunit structure of Escherichia coli exonuclease VII". J. Biol. Chem. 257 (15): 8799–805. doi:10.1016/S0021-9258(18)34201-7 . PMID 6284744.
- ^ a b Huang SN, Michaels SA, Mitchell BB, Majdalani N, Vanden Broeck A, Canela A, Tse-Dinh YC, Lamour V, Pommier Y (March 2021). "Exonuclease VII repairs quinolone-induced damage by resolving DNA gyrase cleavage complexes". Sci Adv. 7 (10). doi:10.1126/sciadv.abe0384. PMC 7929499 . PMID 33658195.
- ^ Repar J, Briški N, Buljubašić M, Zahradka K, Zahradka D (January 2013). "Exonuclease VII is involved in "reckless" DNA degradation in UV-irradiated Escherichia coli". Mutat Res. 750 (1–2): 96–104. doi:10.1016/j.mrgentox.201210005. PMID 23123979.
