The Tn7 transposase is composed of proteins TnsA and TnsB. DNA breakage at the 5' end of the transposon is carried out by TnsA, and breakage and joining at the 3' end is carried out by TnsB. The N terminal domain of TnsA is catalytic [1,2]. This domain is also found in Bacteriophage T4 gp4-like head completion protein whose nuclease activity is required for packaging [3,4]. This domain contains the catalytic triad of one basic and two acidic residues that form a restriction endonuclease-like active site and conserved between TnsA with gp4 proteins [3]. [1]. 10911996. Unexpected structural diversity in DNA recombination: the restriction endonuclease connection. Hickman AB, Li Y, Mathew SV, May EW, Craig NL, Dyda F;. Mol Cell. 2000;5:1025-1034. [2]. 22638584. Sequence, structure and functional diversity of PD-(D/E)XK phosphodiesterase superfamily. Steczkiewicz K, Muszewska A, Knizewski L, Rychlewski L, Ginalski K;. Nucleic Acids Res. 2012;40:7016-7045. [3]. 32056848. Gp4 is a nuclease required for morphogenesis of T4-like bacteriophages. Benler S, Hung SH, Vander Griend JA, Peters GA, Rohwer F, Segall AM;. Virology. 2020;543:7-12. [4]. 33466489. Jumbo Phages: A Comparative Genomic Overview of Core Functions and Adaptions for Biological Conflicts. M Iyer L, Anantharaman V, Krishnan A, Burroughs AM, Aravind L;. Viruses. 2021; [Epub ahead of print] (from Pfam)
- Date:
- 2024-10-16