2qk9

<table><tr><td colspan='2'>[[2qk9]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2QK9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2QK9 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=16D:HEXANE-1,6-DIAMINE'>16D</scene>, <scene name='pdbligand=FLC:CITRATE+ANION'>FLC</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Ribonuclease_H Ribonuclease H], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.26.4 3.1.26.4] </span></td></tr>

[[https://www.uniprot.org/uniprot/RNH1_HUMAN RNH1_HUMAN]] Endonuclease that specifically degrades the RNA of RNA-DNA hybrids.

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== Publication Abstract from PubMed ==

We report here crystal structures of human RNase H1 complexed with an RNA/DNA substrate. Unlike B. halodurans RNase H1, human RNase H1 has a basic protrusion, which forms a DNA-binding channel and together with the conserved phosphate-binding pocket confers specificity for the B form and 2'-deoxy DNA. The RNA strand is recognized by four consecutive 2'-OH groups and cleaved by a two-metal ion mechanism. Although RNase H1 is overall positively charged, the substrate interface is neutral to acidic in character, which likely contributes to the catalytic specificity. Positions of the scissile phosphate and two catalytic metal ions are interdependent and highly coupled. Modeling of HIV reverse transcriptase (RT) with RNA/DNA in its RNase H active site suggests that the substrate cannot simultaneously occupy the polymerase active site and must undergo a conformational change to toggle between the two catalytic centers. The region that accommodates this conformational change offers a target to develop HIV-specific inhibitors.

Structure of human RNase H1 complexed with an RNA/DNA hybrid: insight into HIV reverse transcription.,Nowotny M, Gaidamakov SA, Ghirlando R, Cerritelli SM, Crouch RJ, Yang W Mol Cell. 2007 Oct 26;28(2):264-76. PMID:17964265<ref>PMID:17964265</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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== References ==

<references/>

[[Category: Human]]

[[Category: Cerritelli, S M]]

[[Category: Crouch, R J]]

[[Category: Gaidamakov, S A]]

[[Category: Ghirlando, R]]

[[Category: Nowotny, M]]

[[Category: Yang, W]]

[[Category: Rnase h]]