6bna

[[Image:6bna.jpg|left|200px]]

|PDB= 6bna |SIZE=350|CAPTION= <scene name='initialview01'>6bna</scene>, resolution 2.210&Aring;

 

'''BINDING OF AN ANTITUMOR DRUG TO DNA. NETROPSIN AND C-G-C-G-A-A-T-T-BRC-G-C-G'''

 

 

==Overview==

The antitumor antibiotic netropsin has been co-crystallized with a double-helical B-DNA dodecanucleotide of sequence: C-G-C-G-A-A-T-T-BrC-G-C-G, and the structure of the complex has been solved by X-ray diffraction at a resolution of 2.2 A. The structure has been refined independently by Jack-Levitt and Hendrickson-Konnert least-squares methods, leading to a final residual error of 0.257 by the Jack-Levitt approach (0.211 for two-sigma data) or 0.248 by the Hendrickson-Konnert approach, with no significant difference between refined structures. The netropsin molecule displaces the spine of hydration and fits snugly within the minor groove in the A-A-T-T center. It widens the groove slightly and bends the helix axis back by 8 degrees, but neither unwinds nor elongates the double helix. The drug molecule is held in place by amide NH hydrogen bonds that bridge adenine N-3 and thymine O-2 atoms, exactly as with the spine of hydration. The requirement of A X T base-pairs in the binding site arises because the N-2 amino group of guanine would demand impermissibly close contacts with netropsin. It is proposed that substitution of imidazole for pyrrole in netropsin should create a family of "lexitropsins" capable of reading G X C-containing base sequences.

 

==About this Structure==

6BNA is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6BNA OCA].

 

==Reference==

Binding of an antitumor drug to DNA, Netropsin and C-G-C-G-A-A-T-T-BrC-G-C-G., Kopka ML, Yoon C, Goodsell D, Pjura P, Dickerson RE, J Mol Biol. 1985 Jun 25;183(4):553-63. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/2991536 2991536]

[[Category: Protein complex]]

[[Category: Dickerson, R E.]]

[[Category: Goodsell, D.]]

[[Category: Kopka, M L.]]

[[Category: Pjura, P.]]

[[Category: Yoon, C.]]

[[Category: NT]]

[[Category: b-dna]]

[[Category: complexed with drug]]

[[Category: double helix]]

[[Category: modified]]