Receiver domain of sensor histidine kinase CKI1: Difference between revisions
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==CKI1RD tructure and effects of magnesium binding in the active site== | ==CKI1RD tructure and effects of magnesium binding in the active site== | ||
<StructureSection load='3mmn' size='400' side='right' caption='CKI1RD (PDB entry [[3mmn]])' scene= | <StructureSection load='3mmn' size='400' side='right' caption='CKI1RD (PDB entry [[3mmn]])' scene= | ||
='Receiver_domain/Magnesium_in_cki1rd_asite/6' | ='Receiver_domain/Magnesium_in_cki1rd_asite/6'>' | ||
>The crystal structure of CKI1RD shows the conformational conservation of RDs belonging to CheY-like protein superfamily <ref>PMID:8257674</ref><ref>PMID:19036790</ref>. CKI1RD is folded in a (a/ß)5 manner with central ß-sheet formed from parallel beta-strands (ß2-ß1-ß3-ß4-ß5) surrounded on both sides by two (a1 and a5) and three (a2, a3, a4) a-helices. Secondary structure elements are connected by five loops L1-L5 on the face side of the protein. The active site with phosphoacceptor D1050 is located at the C-termini of the central ß3-strand in a pocket delineated loops L1, L3 and L5. A highly conserved triad of carboxyl oxygens formed by D1050 together with D992 and D993 and carbonyl oxygen of Q1052 give the active site an acidic character. This architecture of the active site is well conserved among CheY-like superfamily and corresponds to the phosphotransfer function of the receiver domains. | >The crystal structure of CKI1RD shows the conformational conservation of RDs belonging to CheY-like protein superfamily <ref>PMID:8257674</ref><ref>PMID:19036790</ref>. CKI1RD is folded in a (a/ß)5 manner with central ß-sheet formed from parallel beta-strands (ß2-ß1-ß3-ß4-ß5) surrounded on both sides by two (a1 and a5) and three (a2, a3, a4) a-helices. Secondary structure elements are connected by five loops L1-L5 on the face side of the protein. The active site with phosphoacceptor D1050 is located at the C-termini of the central ß3-strand in a pocket delineated loops L1, L3 and L5. A highly conserved triad of carboxyl oxygens formed by D1050 together with D992 and D993 and carbonyl oxygen of Q1052 give the active site an acidic character. This architecture of the active site is well conserved among CheY-like superfamily and corresponds to the phosphotransfer function of the receiver domains. | ||