Potential new enzymes in plant NO biosynthesis

• Applicant: Professor Günther Scherer, Ph.D.
• Subject Area: Plant Physiology
• Term: from 2006 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 29119983

This project aims at identifying the source enzyme(s) of polyamine-induced nitric oxide (NO). Polyamine-induced NO synthesis was discovered in the lab of the PI and is unprecedented. In contrast to published information about plant NO synthesizing enzymes, exogenous arginine is less effective than polyamines (putrescine, spermine, spermidine) in inducing rapid NO biosynthesis. As polyamine induction of NO synthesis is very rapid this indicates that perhaps known enzymes of plant NO biosynthesis or a new enzyme group for NO biosynthesis use polyamines as a substrate. The search will encompass the known AtNOS gene family and the polyamine oxidase gene family. The protein identified will be recombinantly purified and tested as a NO synthase and expressed under a chemically controlled promoter in Arabidopsis so that changes in NO biosynthesis and phenotype can be demonstrated. As polyamines have a wide-spread physiological significance in plants the project will give a new foundation to polyamine biology in plants.

• DFG Programme: Research Grants