title: Strong and weak zinc binding sites in human zinc-α2-glycoprotein.
abstract: Zinc-α2-glycoprotein (ZAG) is an adipokine with an MHC class I-like protein fold. Even though zinc causes ZAG to precipitate from plasma during protein purification, no zinc binding has been identified to date. Using mass spectrometry, we demonstrated that ZAG contains one strongly bound zinc ion, predicted to lie close to the α1 and α2 helical groove. UV, CD and fluorescence spectroscopies detected weak zinc binding to holo-ZAG, which can bind up to 15 zinc ions. Zinc binding to 11-(dansylamino) undecanoic acid was enhanced by holo-ZAG. Zinc binding may be important for ZAG binding to fatty acids and the β-adrenergic receptor.
authors.affiliation: Department of Biochemistry, King's College London, Franklin Wilkins Building, 150 Stamford Street, London SE1 9NH, UK.
authors.forename: Aditya Arun
authors.initials: AA
authors.lastname: Kumar
authors.forename: Debolina
authors.initials: D
authors.lastname: Hati
authors.forename: Thana'a Mohajer
authors.initials: TM
authors.lastname: Thaker
authors.forename: Layeque
authors.initials: L
authors.lastname: Miah
authors.forename: Phil
authors.initials: P
authors.lastname: Cunningham
authors.forename: Carmen
authors.initials: C
authors.lastname: Domene
authors.forename: Tam T T
authors.initials: TT
authors.lastname: Bui
authors.forename: Alex F
authors.initials: AF
authors.lastname: Drake
authors.forename: Lindsay C
authors.initials: LC
authors.lastname: McDermott
mesh_terms: D054392:Adipokines; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry* / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism; D006023:Glycoproteins / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs / Q000502:physiology; D017433:Protein Structure, Secondary; D011943:Receptors, Adrenergic, beta / Q000378:metabolism; D013379:Substrate Specificity; D015032:Zinc / Q000737:chemistry / Q000378:metabolism*; D000090203:Zn-Alpha-2-Glycoprotein
chemical_list: D054392:Adipokines; D002352:Carrier Proteins; D005227:Fatty Acids; D006023:Glycoproteins; D011943:Receptors, Adrenergic, beta; D015032:Zinc; C488891:AZGP1 protein, human; D000090203:Zn-Alpha-2-Glycoprotein
keywords: 11-(dansylamino) undecanoic acid; Adipokine; DAUDA; GdnHCl; ICP-MS; MDS; Molecular modeling; Spectroscopy; ZAG; Zinc α2 glycoprotein; guanidinium hydrochloride; inductively coupled plasma-mass spectrometry; molecular dynamics simulations; zinc-α2-glycoprotein