A comparative study of the cowpea and bean strains of southern bean mosaic virus

Features of the primary structure and translation of the genomic RNAs of the cowpea and bean strains of southern bean mosaic virus have been investigated in order to assess the similarity of the two viruses. The sequence of 400 bases at their 3' termini have been determined. These include the 3' noncoding regions and extend well into the coat protein cistrons. The noncoding regions (136 bases for the cowpea strain RNA and 129 bases for the bean strain RNA) show no obvious sequence homology. However, extensive base as well as amino acid sequence homology exists in the coding region. RNAs from both strains have a small protein attached to their 5' terminus-the protein in the cowpea strain being the smaller of the two. In vitro studies show that there are similarities in the overall mode of translation of the genomes of the two viruses. Although corresponding proteins are synthesized they differ in size

Characterization of the Coat Protein mRNA of Southern Bean Mosaic Virus and Its Relationship to the Genomic RNA

RNA isolated from southern bean mosaic virions contains, in small amount, a subgenomic RNA (molecular weight, 0.38 × 10(6)) that serves in vitro as an mRNA for southern bean mosaic virus coat protein. The RNA has a 5′-linked protein indistinguishable from the protein linked to the 5′ end of full-length genomic RNA. Its base sequence, determined to 91 bases from the 3′ end, is identical to the 3′-terminal sequence of the genomic RNA. The results suggest that the coat protein messenger sequence exists as a “silent” cistron near the 3′ end of the genomic RNA

Synthesis of sulfur-containing polyacetylenes and fabrication of their hybrids with ZnO nanoparticles

It has been a challenge to synthesize thiol-functionalized polyacetylenes because of the poisoning effect of mercapto group on the early transition-metal catalysts. Rhodium complexes such as [Rh(cod)Cl](2) can catalyze the polymerizations but the products are insoluble and intractable. In this work, we tackled this challenge. Sulfur-containing polyacetylenes with macroscopic processability were successfully synthesized by separating thiol pendant from polyene backbone with a flexible spacer (in PI), capping free mercapto group with acetyl or alkyl group (in P2 or P3), and using a zwitterionic complex Rh+[eta(6)-C6H5(nbd)B-(C6H5)(3)] as catalyst. The soluble polymers were characterized by NMR, IR, UV, PL, and TGA analyses. Due to the specific interactions between thiol group and zinc cation, ZnO nanoparticles were chemisorbed onto the surfaces of polymer films, as verified by AFM analysis. Polymer P2 and ZnO nanoparticles could be readily hybridized by simply mixing the two components in an organic solvent such as chloroform, THF, or DMF. SEM images revealed that the morphology of the film cast from the solution of the P2/ZnO hybrid was dominated by well-dispersed nanoparticles and smooth surface