Single-enzyme biomineralization of cadmium sulfide nanocrystals with controlled optical properties.
Nature has evolved several unique biomineralization strategies to direct the synthesis and growth of inorganic materials. These natural systems are complex, involving the interaction of multiple biomolecules to catalyze biomineralization and template growth. Herein we describe the first report to our knowledge of a single enzyme capable of both catalyzing mineralization in otherwise unreactive solution and of templating nanocrystal growth. A recombinant putative cystathionine γ-lyase (smCSE) mineralizes CdS from an aqueous cadmium acetate solution via reactive H2S generation from l-cysteine and controls nanocrystal growth within the quantum confined size range. The role of enzymatic nanocrystal templating is demonstrated by substituting reactive Na2S as the sulfur source. Whereas bulk CdS is formed in the absence of the enzyme or other capping agents, nanocrystal formation is observed when smCSE is present to control the growth. This dual-function, single-enzyme, aerobic, and aqueous route to functional material synthesis demonstrates the powerful potential of engineered functional material biomineralization.
Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA 18015;
Robert
R
Dunleavy
Department of Materials Science and Engineering, Lehigh University, Bethlehem, PA 18015;
Li
L
Lu
Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA 18015; Department of Materials Science and Engineering, Lehigh University, Bethlehem, PA 18015;
Christopher J
CJ
Kiely
Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA 18015; bwb209@lehigh.edu stm310@lehigh.edu.
Steven
S
McIntosh
Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA 18015; Program in Bioengineering, Lehigh University, Bethlehem, PA 18015 bwb209@lehigh.edu stm310@lehigh.edu.
Bryan W
BW
Berger
D001688:Biological Products / Q000737:chemistry; D019187:Cadmium Compounds / Q000097:blood*; D002384:Catalysis; D003460:Crystallization / Q000379:methods*; D003542:Cystathionine gamma-Lyase / Q000737:chemistry*; D004789:Enzyme Activation; D008027:Light; D008422:Materials Testing; D008903:Minerals / Q000138:chemical synthesis*; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012031:Refractometry; D012542:Scattering, Radiation; D013440:Sulfides / Q000097:blood*; D013499:Surface Properties
D001688:Biological Products; D019187:Cadmium Compounds; D008903:Minerals; D013440:Sulfides; C034939:cadmium sulfide; D003542:Cystathionine gamma-Lyase
biomineralization; cadmium sulfide; enzyme; nanoparticle; quantum dot