Inhibition of viral capsid assembly by 1,1'-bi(4-anilinonaphthalene-5-sulfonic acid).
The precursor shells of dsDNA bacteriophages are assembled by the polymerization of competent states of coat and scaffolding subunits. The fluorescent dye 1,1'-bi(4-anilinonaphthalene-5-sulfonic acid) (bisANS) binds to both the coat and scaffolding proteins from the Salmonella typhimurium bacteriophage P22. It displays little affinity for the polymerized forms of the proteins. The subunits with bound bisANS are incapable of assembling into procapsids. The binding constants of bisANS for both coat and scaffolding protein monomers have been measured and are 7 and 6 microM, respectively. Binding of bisANS to coat protein has little effect on the conformation as determined by circular dichroism and susceptibility to proteolysis. Binding of bisANS to scaffolding protein induces a change in the secondary structure consistent with a loss of alpha-helix, and an altered susceptibility to proteolysis. We suggest that the bisANS is probably binding at sites responsible for intersubunit interactions and thereby inhibiting capsid assembly.
Teschke
C M
CM
Department of Biology, Massachusetts Institute of Technology, Cambridge 02139.
King
J
J
Prevelige
P E
PE
D000817:Anilino Naphthalenesulfonates / Q000378:metabolism / Q000494:pharmacology*; D000998:Antiviral Agents / Q000494:pharmacology*; D017100:Bacteriophage P22 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D002213:Capsid / Q000096:biosynthesis* / Q000187:drug effects; D002942:Circular Dichroism; D005456:Fluorescent Dyes / Q000494:pharmacology; D007700:Kinetics; D008954:Models, Biological; D011485:Protein Binding; D011487:Protein Conformation; D012486:Salmonella typhimurium / Q000187:drug effects / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D014764:Viral Proteins / Q000096:biosynthesis* / Q000187:drug effects
D000817:Anilino Naphthalenesulfonates; D000998:Antiviral Agents; D005456:Fluorescent Dyes; D014764:Viral Proteins; C035763:5,5'-bis(8-(phenylamino)-1-naphthalenesulfonate)