Structural analyses planning to discover the determinants of raltegravir joining to integrase must help us to comprehend the mechanism of action of this molecule and facilitate the composition based design of second-generation inhibitors. HDAC1 inhibitor Unfortuitously, our understanding of the style of binding of INIs is restricted by an absence of understanding of the composition of the fulllength protein, a precise description of the binding of the metal cation and experimental structural data in regards to the interaction of IN with its viral and cellular DNA substrates. Neither the structure of isolated full-length IN or that of IN in complex with its DNA substrate has yet been determined. Integrase is just a 288 amino acid protein encoded by the end of the pol gene. It is made within the Gag Pol polypeptide precursor, that it is produced by viral protease mediated cleavage. It’s three independent Neuroendocrine tumor domains : the N terminal domain, which holds an HHCC motif analogous to a zinc finger, possibly favoring protein multimerization, a key process in integration, the core domain, covering the catalytic motif, also involved in binding the ends of the viral DNA, notably via residue Q148, which is involved in resistance to raltegravir, the C terminal domain, which binds non specifically to DNA and therefore mainly involved in stabilizing the complex with DNA. The 24 houses available in the Protein data bank describe the three areas separately, or as two domain pieces composed of the catalytic core plus the C terminal domain or the catalytic core plus the N terminal domain. The published X ray structures of the catalytic core domain add a mutation of the F185 deposit introduced to boost the solubility of the enzyme while keeping its catalytic activities in vitro. Crystallization conditions might result in local differences, natural compound library however the topology of all structures obtained are similar. Two houses when the CCD will the cofactor coordinated with the two aspartate residues D64 and D116 have already been identified. The components of the isolated N and C terminal domains have now been dependant on NMR. The X-ray structure of a twodomain construct, comprising the N terminal and CCD areas, was established for that W131D, F139D, F185K double mutant. The asymmetric unit contains four molecules corresponding to two pairs of monomers linked with a low crystallographic two fold axis. Each dimer has well fixed N and CCD terminal domains connected with a highly disordered relating location. The structure of the two dimers varies only slightly when it comes to the relative situation of the two domains, the dihedral angle between these domains differing by 15. The structures of individual domains in this model correspond well to those obtained for the N terminal domains and remote CCD.