1e9s: Difference between revisions

The transfer of DNA across membranes and between cells is a central, biological process; however, its molecular mechanism remains unknown. In, prokaryotes, trans-membrane passage by bacterial conjugation, is the main, route for horizontal gene transfer. It is the means for rapid acquisition, of new genetic information, including antibiotic resistance by pathogens., Trans-kingdom gene transfer from bacteria to plants or fungi and even, bacterial sporulation are special cases of conjugation. An integral, membrane DNA-binding protein, called TrwB in the Escherichia coli R388, conjugative system, is essential for the conjugation process. This large, multimeric protein is responsible for recruiting the relaxosome, DNA-protein complex, and participates in the transfer of a single DNA, strand during cell mating. Here we report the three-dimensional structure, of a soluble variant of TrwB. The molecule consists of two domains: a, nucleotide-binding domain of alpha/beta topology, reminiscent of RecA and, DNA ring helicases, and an all-alpha domain. Six equivalent protein, monomers associate to form an almost spherical quaternary structure that, is strikingly similar to F1-ATPase. A central channel, 20 A in width, traverses the hexamer.

1E9S is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Structure known Active Site: NBS. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1E9S OCA].  

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