RESUMO
In the past years, stereoselective functionalizations of hydroxyl groups of alcohol substrates with chlorosilanes leading to silyl ether formation have evolved from a functional-group protection to an enantioselective synthetic strategy. This work comprises a controlled desymmetrization of dichlorosilanes by using a family of structurally specific chiral diols, chiral 1,1'-binaphthalene-2-α-arylmethanol-2'-ol (Ar-BINMOL). This process led to the facile construction of silicon-stereogenic organosilicon compounds with high yields and good diastereoselectivities. In addition, the diasteroselective silylation of chiral diols might not only be of interest for the development of highly stereoselective nucleophilic silylation, but also shed light on the construction of novel chiral phosphine ligands bearing a silicon-stereogenic center.
RESUMO
The capsid protein (CP) of duck circovirus (DuCV) is the major immunogenic protein and has a high proportion of arginine residues concentrated at the N terminus of the protein, which inhibits efficient mRNA translation in prokaryotic expression systems. In this study, we investigated the subcellular distribution of DuCV CP expressed via recombinant baculoviruses in Sf9 cells and the DNA binding activities of the truncated recombinant DuCV CPs. The results showed that two independent bipartite nuclear localization signals (NLSs) situated at N-terminal 1-17 and 18-36 amino acid residue of the CP. Moreover, two expression level regulatory signals (ELRSs) and two DNA binding signals (DBSs) were also mapped to the N terminus of the protein and overlapped with the two NLSs. The ability of CP to bind DNA, coupled with the karyophilic nature of this protein, strongly suggests that it may be responsible for nuclear targeting of the viral genome.
Assuntos
Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Circovirus/metabolismo , Sinais de Localização Nuclear/metabolismo , Animais , Baculoviridae/genética , Proteínas do Capsídeo/genética , Linhagem Celular , Núcleo Celular/metabolismo , Circovirus/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Patos/virologia , Genoma Viral , Sinais de Localização Nuclear/química , Sinais de Localização Nuclear/genética , Proteínas Recombinantes/metabolismo , Células Sf9 , Transdução de Sinais , Replicação ViralRESUMO
Infection with duck circovirus (DuCV) is associated with growth retardation and developmental problems in farmed ducks. To detect DuCV-specific antibody in duck serum, an indirect enzyme-linked immunosorbent assay (iELISA) method was developed using the recombinant capsid protein antigen prepared by cloning the cap (Cap) gene of DuCV FJ0601 strain into pET-32a (+) vector and expressed in Escherichia coli. Using the optimized iELISA method, DuCV-specific antibodies were detected in 157 (12.96%) of 1211 samples obtained from 17 (89.47%) of 19 meat duck flocks aged from 25 to 40 days and in 89 (22.08%) of 403 samples obtained from 9 (75%) of 12 breeder flocks aged from 14 to 61 weeks. These results indicated that the iELISA method is useful for serological diagnosis of DuCV infection and epidemiological investigation.
