Chlorophyll Breakdown Products as a Tool for Studying Plant Cellular Processes

The breakdown of chlorophyll in ripening fruits such as apple and pear, similar to the breakdown of green to yellow and red pigments in senescing leaves during autumn, produces decomposition products called non-fluorescing chlorophyll catabolites (NCC). In bananas, however, chlorophylls fade to give unique fluorescent catabolites (FCCs), causing yellow bananas to glow blue when viewed under the UV light. Recently, a team of researchers from Austria found that these fluorescent catabolites can signal symptoms of cell suicide in plants. Bernhard Krautler and colleagues found that FCCs accumulate in luminescent halos around dark spots that appear naturally in the peel of ripening bananas, within senescing cells undergoing transition to dead tissues. The scientists, in a paper published by PNAS, wrote that "fruit eating animals might have learned, through survival pressure, to notice the blue luminescence of FCCs in ripening bananas, and the characteristic rings that develop as halos on the spotted peels of very ripe bananas."

Krautler and colleagues said that these catabolites "may prove to be helpful as a noninvasive, molecular tool for studying cellular processes in plants."

The paper is available at http://dx.doi.org10.1073/pnas.0908060106