5HNK
Crystal structure of T5Fen in complex intact substrate and metal ions.
Summary for 5HNK
| Entry DOI | 10.2210/pdb5hnk/pdb |
| Related | 5HML |
| Descriptor | DNA (5'-D(*AP*AP*AP*AP*GP*CP*GP*TP*AP*CP*GP*C)-3'), Exodeoxyribonuclease, MAGNESIUM ION, ... (6 entities in total) |
| Functional Keywords | hydrolase, enzyme-dna complex, flap endonuclease, metalloenzyme. |
| Biological source | Escherichia phage T5 More |
| Total number of polymer chains | 4 |
| Total formula weight | 70091.62 |
| Authors | Almalki, F.A.,Feng, M.,Zhang, J.,Sedelnikova, S.E.,Rafferty, J.B.,Sayers, J.R.,Artymiuk, P.J. (deposition date: 2016-01-18, release date: 2016-06-01, Last modification date: 2024-01-10) |
| Primary citation | AlMalki, F.A.,Flemming, C.S.,Zhang, J.,Feng, M.,Sedelnikova, S.E.,Ceska, T.,Rafferty, J.B.,Sayers, J.R.,Artymiuk, P.J. Direct observation of DNA threading in flap endonuclease complexes. Nat.Struct.Mol.Biol., 23:640-646, 2016 Cited by PubMed Abstract: Maintenance of genome integrity requires that branched nucleic acid molecules be accurately processed to produce double-helical DNA. Flap endonucleases are essential enzymes that trim such branched molecules generated by Okazaki-fragment synthesis during replication. Here, we report crystal structures of bacteriophage T5 flap endonuclease in complexes with intact DNA substrates and products, at resolutions of 1.9-2.2 Å. They reveal single-stranded DNA threading through a hole in the enzyme, which is enclosed by an inverted V-shaped helical arch straddling the active site. Residues lining the hole induce an unusual barb-like conformation in the DNA substrate, thereby juxtaposing the scissile phosphate and essential catalytic metal ions. A series of complexes and biochemical analyses show how the substrate's single-stranded branch approaches, threads through and finally emerges on the far side of the enzyme. Our studies suggest that substrate recognition involves an unusual 'fly-casting, thread, bend and barb' mechanism. PubMed: 27273516DOI: 10.1038/nsmb.3241 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.22 Å) |
Structure validation
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