Assembly of hybrid bacteriophage Qbeta virus-like particles.
Bacteriophage Qbeta coat protein forms uniform virus-like particles when expressed recombinantly in a variety of organisms. We have inserted the IgG-binding Z domain at the carboxy terminus of the coat protein and coexpressed this chimeric subunit with native coat protein to create hybrid, IgG-binding virus-like particles. Extracellular osmolytes were found to have an effect on the efficiency of incorporation of fusion proteins into VLPs in Escherichia coli when a carbenicillin, but not a kanamycin, selection marker was used. The addition of sucrose to the growth medium decreased the incorporation efficiency; the osmoprotectant glycine betaine eliminated this effect. The decrease in efficiency was not observed when carbenicillin was omitted from the final expression culture. The addition of sodium chloride instead of sucrose gave rise to particles with a larger number of fusion proteins than the standard conditions. These results illustrate that cellular conditions should be taken into account even in apparently simple systems when natural or engineered protein nanoparticles are made.
Department of Chemistry and The Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Steven D
SD
Brown
Jason D
JD
Fiedler
M G
MG
Finn
D017908:Allolevivirus / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D001622:Betaine / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D036022:Capsid Proteins / Q000378:metabolism*; D002228:Carbenicillin / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects; D005110:Extracellular Space / Q000378:metabolism; D007074:Immunoglobulin G / Q000378:metabolism; D007612:Kanamycin / Q000494:pharmacology; D008082:Lipotropic Agents / Q000737:chemistry / Q000378:metabolism; D012965:Sodium Chloride / Q000737:chemistry; D013395:Sucrose / Q000737:chemistry; D013499:Surface Properties; D019065:Virus Assembly
D036022:Capsid Proteins; D007074:Immunoglobulin G; D008082:Lipotropic Agents; C043366:coat protein, Bacteriophage Qbeta; D001622:Betaine; D012965:Sodium Chloride; D013395:Sucrose; D007612:Kanamycin; D002228:Carbenicillin