title: Enzymatic Dissolution of Biocomposite Solids Consisting of Phosphopeptides to Form Supramolecular Hydrogels.
abstract: Enzyme-catalyzed dephosphorylation is essential for biomineralization and bone metabolism. Here we report the exploration of using enzymatic reaction to transform biocomposites of phosphopeptides and calcium (or strontium) ions to supramolecular hydrogels as a mimic of enzymatic dissolution of biominerals. (31) P NMR shows that strong affinity between the phosphopeptides and alkaline metal ions (e.g., Ca(2+) or Sr(2+) ) induces the formation of biocomposites as precipitates. Electron microscopy reveals that the enzymatic reaction regulates the morphological transition from particles to nanofibers. Rheology confirms the formation of a rigid hydrogel. As the first example of enzyme-instructed dissolution of a solid to form supramolecular nanofibers/hydrogels, this work provides an approach to generate soft materials with desired properties, expands the application of supramolecular hydrogelators, and offers insights to control the demineralization of calcified soft tissues.
authors.affiliation: Department of Chemistry, Brandeis University, 415 South St, Waltham, MA 02454 (USA), Fax: (+1) 781-736-2516.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Shi
authors.affiliation: Department of Chemistry, Brandeis University, 415 South St, Waltham, MA 02454 (USA), Fax: (+1) 781-736-2516.
authors.forename: Dan
authors.initials: D
authors.lastname: Yuan
authors.affiliation: Department of Chemistry, Brandeis University, 415 South St, Waltham, MA 02454 (USA), Fax: (+1) 781-736-2516.
authors.forename: Richard
authors.initials: R
authors.lastname: Haburcak
authors.affiliation: Division of Physical Science & Engineering and Core Lab, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia).
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Division of Physical Science & Engineering and Core Lab, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia).
authors.forename: Chao
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Division of Physical Science & Engineering and Core Lab, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia).
authors.forename: Xixiang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, Brandeis University, 415 South St, Waltham, MA 02454 (USA), Fax: (+1) 781-736-2516. bxu@brandeis.edu.
authors.forename: Bing
authors.initials: B
authors.lastname: Xu
mesh_terms: D055162:Biocatalysis; D002113:Calcification, Physiologic; D002118:Calcium / Q000737:chemistry*; D006801:Humans; D020100:Hydrogels / Q000138:chemical synthesis / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D010748:Phosphopeptides / Q000737:chemistry* / Q000378:metabolism*; D010766:Phosphorylation; D012212:Rheology / Q000379:methods; D013324:Strontium / Q000737:chemistry*
chemical_list: D020100:Hydrogels; D010748:Phosphopeptides; D002118:Calcium; D013324:Strontium
keywords: bone mineralization; enzyme; phosphopeptide; self-assembly; solid-gel transition