Thiol‐dependent degradation of protoporphyrin IX by plant peroxidases

FEBS Letters

Duke, S.O²  Rimando, A.M²  Jacobs, N.J¹  Dayan, F.E² 

[1] Department of Microbiology, Dartmouth Medical School, Hanover, NH 03755, USA;USDA/ARS Natural Products Utilization Research Unit, P.O. Box 8048, University, MS 38677, USA

关键词: Porphyrin;    Tetrapyrrole;    Degradation;    Breakdown;    Turn-over;   

DOI  :  10.1016/S0014-5793(99)00065-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Protoporphyrin IX (PP) is the last porphyrin intermediate in common between heme and chlorophyll biosynthesis. This pigment normally does not accumulate in plants because its highly photodynamic nature makes it toxic. While the steps leading to heme and chlorophylls are well characterized, relatively little is known of the metabolic fate of excess PP in plants. We have discovered that plant peroxidases can rapidly degrade this pigment in the presence of thiol-containing substrates such as glutathione and cysteine. This thiol-dependent degradation of PP by horseradish peroxidase consumes oxygen and is inhibited by ascorbic acid.

【 授权许可】

Unknown