title: Orthopoxvirus species and strain differences in cell entry.
abstract: Vaccinia virus (VACV) enters cells by a low pH endosomal route or by direct fusion with the plasma membrane. We previously found differences in entry properties of several VACV strains: entry of WR was enhanced by low pH, reduced by bafilomycin A1 and relatively unaffected by heparin, whereas entry of IHD-J, Copenhagen and Elstree were oppositely affected. Since binding and entry modes may have been selected by specific conditions of in vitro propagation, we now examined the properties of three distinct, recently isolated cowpox viruses and a monkeypox virus as well as additional VACV and cowpox virus strains. The recent isolates were more similar to WR than to other VACV strains, underscoring the biological importance of endosomal entry by orthopoxviruses. Sequence comparisons, gene deletions and gene swapping experiments indicated that viral determinants, other than or in addition to the A26 and A25 "fusion-suppressor" proteins, impact entry properties.
authors.affiliation: Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-3210, USA.
authors.forename: Zain
authors.initials: Z
authors.lastname: Bengali
authors.forename: P S
authors.initials: PS
authors.lastname: Satheshkumar
authors.forename: Bernard
authors.initials: B
authors.lastname: Moss
mesh_terms: D000818:Animals; D002460:Cell Line; D002522:Chlorocebus aethiops; D015608:Cowpox virus / Q000472:pathogenicity / Q000502:physiology; D011992:Endosomes / Q000821:virology; D006025:Glycosaminoglycans / Q000494:pharmacology; D006367:HeLa Cells; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D018942:Macrolides / Q000494:pharmacology; D008993:Monkeypox virus / Q000472:pathogenicity / Q000502:physiology; D016366:Open Reading Frames; D018155:Orthopoxvirus / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D013045:Species Specificity; D014616:Vaccinia virus / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology; D053586:Virus Internalization / Q000187:drug effects
chemical_list: D006025:Glycosaminoglycans; D018942:Macrolides; C040929:bafilomycin A1; D006493:Heparin