2lel
From Proteopedia
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== Structural highlights == | == Structural highlights == | ||
[[2lel]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Cupriavidus_metallidurans Cupriavidus metallidurans]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LEL OCA]. <br> | [[2lel]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Cupriavidus_metallidurans Cupriavidus metallidurans]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LEL OCA]. <br> | ||
| + | <b>[[Ligand|Ligands:]]</b> <scene name='pdbligand=CU:COPPER+(II)+ION'>CU</scene>, <scene name='pdbligand=CU1:COPPER+(I)+ION'>CU1</scene><br> | ||
<b>Activity:</b> <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span><br> | <b>Activity:</b> <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span><br> | ||
| + | <b>Resources:</b> <span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2lel FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2lel OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2lel RCSB], [http://www.ebi.ac.uk/pdbsum/2lel PDBsum]</span><br> | ||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
The bacterium Cupriavidus metallidurans CH34 is resistant to high environmental concentrations of many metal ions. Upon copper challenge, it upregulates the periplasmic protein CopK (8.3 kDa). The function of CopK in the copper resistance response is ill-defined, but CopK demonstrates an intriguing cooperativity: occupation of a high-affinity Cu(I) binding site generates a high-affinity Cu(II) binding site, and the high-affinity Cu(II) binding enhances Cu(I) binding. Native CopK and targeted variants were examined by chromatographic, spectroscopic, and X-ray crystallographic probes. Structures of two distinct forms of Cu(I)Cu(II)-CopK were defined, and structural changes associated with occupation of the Cu(II) site were demonstrated. In solution, monomeric Cu(I)Cu(II)-CopK features the previously elucidated Cu(I) site in Cu(I)-CopK, formed from four S(delta) atoms of Met28, -38, -44, and -54 (site 4S). Binding of Cu(I) to apo-CopK induces a conformational change that releases the C-terminal beta-strand from the beta-sandwich structure. In turn, this allows His70 and N-terminal residues to form a large loop that includes the Cu(II) binding site. In crystals, a polymeric form of Cu(I)Cu(II)-CopK displays a Cu(I) site defined by the S(delta) atoms of Met26, -38, and -54 (site 3S) and an exogenous ligand (modeled as H(2)O) and a Cu(II) site that bridges dimeric CopK molecules. The 3S Cu(I) binding mode observed in crystals was demonstrated in solution in protein variant M44L where site 4S is disabled. The intriguing copper binding chemistry of CopK provides molecular insight into Cu(I) transfer processes. The adaptable nature of the Cu(I) coordination sphere in methionine-rich clusters allows copper to be relayed between clusters during transport across membranes in molecular pumps such as CusA and Ctr1. | The bacterium Cupriavidus metallidurans CH34 is resistant to high environmental concentrations of many metal ions. Upon copper challenge, it upregulates the periplasmic protein CopK (8.3 kDa). The function of CopK in the copper resistance response is ill-defined, but CopK demonstrates an intriguing cooperativity: occupation of a high-affinity Cu(I) binding site generates a high-affinity Cu(II) binding site, and the high-affinity Cu(II) binding enhances Cu(I) binding. Native CopK and targeted variants were examined by chromatographic, spectroscopic, and X-ray crystallographic probes. Structures of two distinct forms of Cu(I)Cu(II)-CopK were defined, and structural changes associated with occupation of the Cu(II) site were demonstrated. In solution, monomeric Cu(I)Cu(II)-CopK features the previously elucidated Cu(I) site in Cu(I)-CopK, formed from four S(delta) atoms of Met28, -38, -44, and -54 (site 4S). Binding of Cu(I) to apo-CopK induces a conformational change that releases the C-terminal beta-strand from the beta-sandwich structure. In turn, this allows His70 and N-terminal residues to form a large loop that includes the Cu(II) binding site. In crystals, a polymeric form of Cu(I)Cu(II)-CopK displays a Cu(I) site defined by the S(delta) atoms of Met26, -38, and -54 (site 3S) and an exogenous ligand (modeled as H(2)O) and a Cu(II) site that bridges dimeric CopK molecules. The 3S Cu(I) binding mode observed in crystals was demonstrated in solution in protein variant M44L where site 4S is disabled. The intriguing copper binding chemistry of CopK provides molecular insight into Cu(I) transfer processes. The adaptable nature of the Cu(I) coordination sphere in methionine-rich clusters allows copper to be relayed between clusters during transport across membranes in molecular pumps such as CusA and Ctr1. | ||
Revision as of 10:19, 30 April 2014
Structure of Cu(I)Cu(II)-CopK from Cupriavidus metallidurans CH34
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