Fig. 1.
The pathway of chl catabolism, and identification of possible PaO proteins in A. thaliana.(A) The pathway of chl catabolism. The key reaction is catalyzed by the joint action of PaO and RCCR. Chemical constitutions of chl catabolites are shown. Pyrrole rings (A–D), methine bridges (α-δ), and relevant carbon atoms are labeled. NCCs are species-specifically modified at different side positions (R1-R3). (B) Screening of the ATH1.pep database of the Arabidopsis Genome Initiative (AGI Proteins) for proteins with known properties of PaO.