Specificity of Virus Reconstitution between Tobacco Mosaic Virus Strains and Infectivity of Reconstituted Viruses

Hybrid virus particles were reconstituted by RNA and protein extracted from tobacco mosaic virus crucifer strain (C) and ordinary strain (OM), or C and Bean strain (B). The reconstituted viral yield of the combination ‘C-RNA+OM-protein’ was markedly lower than those of the other combinations. According to sucrose density gradient centrifugation of the reconstituted substances prepared from the combination ‘C-RNA+OM-protein’, the virus particles of 300mμ in length were smaller in number. On the other hand, C-protein reacted sufficiently with OM-RNA or B-RNA, and they formed efficiently the complete virus particles. The reconstituted virus ‘OM-RNA+C-protein’ revealed similar specific infectivity to the reconstituted virus ‘OM-RNA+OM-protein’. Specific infectivity of the reconstituted viruses was almost equal to that of the standard virus (intact OM) on the primary leaves of Phaseolus vulgaris whereas the former was lower than the latter on the leaves of Nicotiana glutinosa. The reconstituted viruses were more sensitive to RNase than the standard virus.