RESUMO
The viral genome-linked protein (VPg) of Potyviruses is covalently attached to the 5’ end of the genomic RNA. Towards biophysical characterization, the VPg coding region of Cardamom mosaic virus (CdMV) was amplified from the cDNA and expressed in E. coli. Most of the expressed VPg aggregated as inclusion bodies that were solubilized with urea and refolded with L-arginine hydrochloride. The various forms of CdMV VPg (native, denatured and refolded) were purified and the conformational variations between these forms were observed with fluorescence spectroscopy. Native and refolded CdMV VPg showed unordered secondary structure in the circular dichroism (CD) spectrum. The model of CdMV VPg was built based on the crystal structure of phosphotriesterase (from Pseudomonas diminuta), which had the maximum sequence homology with VPg to identify the arrangement of conserved amino acids in the protein to study the functional diversity of VPg. This is the first report on the VPg of CdMV, which is classified as a new member of the Macluravirus genus of the Potyviridae family.
Assuntos
Dicroísmo Circular , Elettaria/metabolismo , Genoma Viral/genética , Corpos de Inclusão/genética , Corpos de Inclusão/metabolismo , Modelos Moleculares , Vírus do Mosaico/genética , Vírus do Mosaico/metabolismo , Vírus de Plantas/genética , Vírus de Plantas/metabolismo , Potyvirus/genética , Potyvirus/metabolismo , Redobramento de Proteína , Estrutura Secundária de Proteína , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/isolamento & purificação , Proteínas de Ligação a RNA/metabolismo , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
An aqueous suspension of cardamom, Elettaria cardamomum was tested for its ability to inhibit gastric secretion and to protect gastric mucosa against the injuries caused by pylorus ligation, indomethacin and cytodestructive agents [80% ethanol, 0.2 M NaOH and 25% NaCI] in rats. The cardamom suspension at doses [250 and 500 mg/kg] exhibited significant decrease in basal gastric secretions and ulcers induced by Shay rats and indomethacin in rats. The suspension also significantly protected gastric mucosal against necrotizing agents. Histopathological evaluation revealed no significant pathological changes in the stomach of rats after 80% ethanol challenge. The LD[50] of cardamom was found to be 26.0 g/kg in mice. A large margin of safety was observed in animals in acute and chronic toxicity tests. Treatment with cardamom suspension did not induce any significant changes in the micronucleated polychromatic erythrocytes [PCE] and the ratio of PCE and normochromatic erythrocytes [NCE] at both doses used as compared to control group. In conclusion, cardamom showed a significant antisecretory and antiulcer activities without causing any deleterious effects in acute, prolong administration and genotoxicity in the animals