3twh is a 3 chain structure with sequence from Alkalihalobacillus halodurans. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
↑ Nowotny M, Gaidamakov SA, Crouch RJ, Yang W. Crystal structures of RNase H bound to an RNA/DNA hybrid: substrate specificity and metal-dependent catalysis. Cell. 2005 Jul 1;121(7):1005-16. PMID:15989951 doi:http://dx.doi.org/10.1016/j.cell.2005.04.024