6rk9
From Proteopedia
Aspartyl/Asparaginyl beta-hydroxylase (AspH)oxygenase and TPR domains in complex with manganese, N-oxalylglycine and cyclic peptide substrate mimic of factor X
Structural highlights
FunctionASPH_HUMAN Isoform 1: specifically hydroxylates an Asp or Asn residue in certain epidermal growth factor-like (EGF) domains of a number of proteins.[1] Isoform 8: membrane-bound Ca(2+)-sensing protein, which is a structural component of the ER-plasma membrane junctions. Isoform 8 regulates the activity of Ca(+2) released-activated Ca(+2) (CRAC) channels in T-cells.[2] Publication Abstract from PubMedAspH is an endoplasmic reticulum (ER) membrane-anchored 2-oxoglutarate oxygenase whose C-terminal oxygenase and tetratricopeptide repeat (TPR) domains present in the ER lumen. AspH catalyses hydroxylation of asparaginyl- and aspartyl-residues in epidermal growth factor-like domains (EGFDs). Here we report crystal structures of human AspH, with and without substrate, that reveal substantial conformational changes of the oxygenase and TPR domains during substrate binding. Fe(II)-binding by AspH is unusual, employing only two Fe(II)-binding ligands (His679/His725). Most EGFD structures adopt an established fold with a conserved Cys1-3, 2-4, 5-6 disulfide bonding pattern; an unexpected Cys3-4 disulfide bonding pattern is observed in AspH-EGFD substrate complexes, the catalytic relevance of which is supported by studies involving stable cyclic peptide substrate analogues and by effects of Ca(II) ions on activity. The results have implications for EGFD disulfide pattern processing in the ER and will enable medicinal chemistry efforts targeting human 2OG oxygenases. Aspartate/asparagine-beta-hydroxylase crystal structures reveal an unexpected epidermal growth factor-like domain substrate disulfide pattern.,Pfeffer I, Brewitz L, Krojer T, Jensen SA, Kochan GT, Kershaw NJ, Hewitson KS, McNeill LA, Kramer H, Munzel M, Hopkinson RJ, Oppermann U, Handford PA, McDonough MA, Schofield CJ Nat Commun. 2019 Oct 28;10(1):4910. doi: 10.1038/s41467-019-12711-7. PMID:31659163[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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