RESUMO
Suspension cultures of Abronia nana were established to produce C-methylisoflavones. Treatment of the A. nana cultures with yeast elicitor induced boeravinone E (1), with maximum induction at 24 h after elicitor treatment. Of the biotic and abiotic elicitors tested, yeast extract gave the strongest induction of 1. The IC50 value of 1 against ß-secretase (ß-amyloid cleaving enzyme-1) was 5.57 µM. Other proteases such as trypsin, chymotrypsin, and elastase were not inhibited by concentrations up to 1.0 mM, indicating that inhibition of ß-secretase was specific. 1 was noncompetitive in Dixon plot, and Ki value was 3.79 µM.
Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Meios de Cultura/metabolismo , Flavonoides/biossíntese , Nyctaginaceae/enzimologia , Proteínas de Plantas/metabolismo , Leveduras/química , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Células Cultivadas , Nyctaginaceae/crescimento & desenvolvimento , Nyctaginaceae/metabolismo , Proteínas de Plantas/antagonistas & inibidoresRESUMO
A full-length cDNA encoding ribosome-inactivating/antiviral protein from the leaves of Bougainvillea xbuttiana was recently isolated. The coding region of cDNA was cloned and expressed in Escherichia coli, and the protein product was designated as BBAP1 (Bougainvillea xbuttiana antiviral protein 1). BBAP1 showed ribonuclease activity against Torula yeast RNA. It also exhibited depurination activity against supercoiled pBlueScript SK+ plasmid DNA in a concentration dependent manner, and was found to convert nicked circular DNA into linear form only at higher concentration. On bioassay, BBAP1 exhibited antiviral activity against sunnhemp rosette virus infecting Cyamopsis tetragonoloba leaves in which 95% inhibition of local lesion formation was observed.
Assuntos
Antivirais/farmacologia , Desoxirribonucleases/metabolismo , Nyctaginaceae/enzimologia , Ribonucleases/metabolismo , Proteínas Inativadoras de Ribossomos/metabolismo , Proteínas Inativadoras de Ribossomos/farmacologia , Antivirais/química , Desoxirribonucleases/genética , Escherichia coli/genética , Expressão Gênica , Proteínas Recombinantes , Ribonucleases/genética , Proteínas Inativadoras de Ribossomos/genéticaRESUMO
An antiviral protein from Bougainvillea xbuttiana leaves induced systemic resistance in host plants N. glutinosa and Cyamopsis tetragonoloba against TMV and SRV, respectively which was reversed by actinomycin D, when applied immediately or shortly after antiviral protein treatment. When the inhibitor was applied to the host plant leaves post inoculation, it was effective if applied upto 4 h after virus infection. It also delayed the expression of symptoms in systemic hosts of TMV. The inhibitor showed characteristic N-glycosidase activity on 25S rRNA of tobacco ribosomes, suggesting that it could also be interfering with virus multiplication through ribosome-inactivation process.
