title: Two-Dimensional Crystallization of P22 Virus-Like Particles.
abstract: Virus-like particles (VLPs) are well established platforms for constructing functional biomimetic materials. The VLP from the bacteriophage P22 can be used as a nanocontainer to sequester active enzymes, at high concentration, within its cavity through a process of directed self-assembly. Construction of ordered 2D assemblies of these catalytic VLPs can be envisioned as a functional membrane. To achieve this, it is important to establish methods to fabricate densely packed monolayers of VLPs. Highly ordered assemblies of P22 can also be utilized as a two-dimensional (2D) crystal for electron crystallography to get precise structural information on the VLP. Here we report 2D crystallization of different P22 morphologies: P22 procapsid (PC), enzyme encapsulated PC (β-glycosidase and enhanced green fluorescent protein), empty shell (PC without scaffold proteins, ES), the expanded form of P22 (EX), and enzyme encapsulated EX (NADH oxidase). The 2D crystals of P22 VLPs were formed on a positively charged lipid monolayer at the water-air interface with a subphase containing 1% trehalose. A P22 solution, injected underneath the lipid monolayer, floated to the surface because of the density difference between the subphase and protein solution. The lipid monolayer, with adsorbed P22, was transferred to a holey carbon grid and was examined by electron microscopy. 2D crystals were obtained from a subphase containing 100 mM NaCl, 10 mM MES (pH 5.0), and 1% trehalose. The diffraction spots from the transferred film extended to the sixth order in negatively stained samples and the 10th order in cryo-electron microscopy samples.
authors.affiliation: Department of Physics, Meiji University , 1-1-1 Higashimita, Tama-ku, Kawasaki, 214-8571, Japan.|Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Yoshimura
authors.affiliation: Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
authors.forename: Ethan
authors.initials: E
authors.lastname: Edwards
authors.affiliation: Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
authors.forename: Masaki
authors.initials: M
authors.lastname: Uchida
authors.affiliation: Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
authors.forename: Kimberly
authors.initials: K
authors.lastname: McCoy
authors.affiliation: Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
authors.forename: Raj
authors.initials: R
authors.lastname: Roychoudhury
authors.affiliation: Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Schwarz
authors.affiliation: Department of Chemistry & Biochemistry, University of Texas at Tyler , 3900 University Boulevard, Tyler, Texas 75799, United States.
authors.forename: Dustin
authors.initials: D
authors.lastname: Patterson
authors.affiliation: Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
authors.forename: Trevor
authors.initials: T
authors.lastname: Douglas
mesh_terms: D000388:Air / Q000032:analysis; D017100:Bacteriophage P22 / Q000737:chemistry* / Q000648:ultrastructure; D040761:Biomimetic Materials / Q000737:chemistry*; D020285:Cryoelectron Microscopy; D003460:Crystallization / Q000379:methods*; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D004339:Drug Compounding; D049452:Green Fluorescent Proteins / Q000737:chemistry; D009097:Multienzyme Complexes / Q000737:chemistry; D009226:Myristates / Q000737:chemistry; D009247:NADH, NADPH Oxidoreductases / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D055672:Static Electricity; D013499:Surface Properties; D014199:Trehalose / Q000737:chemistry; D014771:Virion / Q000737:chemistry* / Q000648:ultrastructure; D014867:Water / Q000737:chemistry; D001617:beta-Glucosidase / Q000737:chemistry
chemical_list: C117241:1,2-dimyristoyl-3-trimethylammonium propane; D009097:Multienzyme Complexes; D009226:Myristates; D000644:Quaternary Ammonium Compounds; C485184:enhanced green fluorescent protein; D014867:Water; D049452:Green Fluorescent Proteins; D014199:Trehalose; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D001617:beta-Glucosidase; D004134:Dimyristoylphosphatidylcholine