Division of Biochemistry, Indian Agricultural Research Institute, New Delhi 110 012, India
*Corresponding author. E-mail: mll_bio@iari.res.in
Abbreviations: AVPs, antiviral proteins; CAT, catalase; FRAP, ferric reducing/antioxidant power; HR, hypersensitive response; POD, peroxidase; ROS, reactive oxygen species; SA, salicylic acid; SAR, systemic acquired resistance; SOD, superoxide dismutase; SRV, sunnhemp rosette virus; TMV, tobacco mosaic virus.
Bougainvillea xbuttiana antiviral proteins (AVPs) exhibited high antioxidant activity as measured by ferric reducing/antioxidant (FRAP) power assay. These AVPs were also found to modify activities of antioxidant enzymes like superoxide dismutase, peroxidase and catalase. The activities of superoxide dismutase and peroxidase increased, while the activity of catalase decreased in Tobacco mosaic virus (TMV) infected tobacco leaves. The trend was reversed when the leaves were treated with AVP alone. However, in TMV + AVP treated leaves, the activities of all the three enzymes were found to be midway between the activities obtained with other two treatments. It is therefore, suggested that Bougainvillea AVPs might be controlling viral diseases by scavenging reactive oxygen species as well as by altering host plant cell metabolism to maintain its antioxidant status.
Bougainvillea xbuttiana, antiviral proteins, antioxidant activity, oxidoreductases
