title: Cascade biocatalysis by multienzyme-nanoparticle assemblies.
abstract: Multienzyme complexes are of paramount importance in biosynthesis in cells. Yet, how sequential enzymes of cascade catalytic reactions synergize their activities through spatial organization remains elusive. Recent development of site-specific protein-nanoparticle conjugation techniques enables us to construct multienzyme assemblies using nanoparticles as the template. Sequential enzymes in menaquinone biosynthetic pathway were conjugated to CdSe-ZnS quantum dots (QDs, a nanosized particulate material) through metal-affinity driven self-assembly. The assemblies were characterized by electrophoretic methods, the catalytic activities were monitored by reverse-phase chromatography, and the composition of the multienzyme-QD assemblies was optimized through a progressive approach to achieve highly efficient catalytic conversion. Shorter enzyme-enzyme distance was discovered to facilitate intermediate transfer, and a fine control on the stoichiometric ratio of the assembly was found to be critical for the maximal synergy between the enzymes. Multienzyme-QD assemblies thereby provide an effective model to scrutinize the synergy of cascade enzymes in multienzyme complexes.
authors.affiliation: Department of Chemistry, The Chinese University of Hong Kong , Shatin, Hong Kong SAR, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Kang
authors.forename: Jiahui
authors.initials: J
authors.lastname: Liu
authors.forename: Jianpeng
authors.initials: J
authors.lastname: Wang
authors.forename: Yunyu
authors.initials: Y
authors.lastname: Nie
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Guo
authors.forename: Jiang
authors.initials: J
authors.lastname: Xia
mesh_terms: D055162:Biocatalysis; D008958:Models, Molecular; D009097:Multienzyme Complexes / Q000737:chemistry* / Q000378:metabolism*; D011487:Protein Conformation; D045663:Quantum Dots / Q000737:chemistry*
chemical_list: D009097:Multienzyme Complexes