Pyropheophorbide und a as a catabolite of ethylene-induced chlorophyll und a degradation

Conference · Tue May 01 00:00:00 EDT 1990 · Plant Physiology, Supplement; (USA)

OSTI ID:5644953

Shimokawa, Keishi; Hashizume, Akihito ^[1]; Shioi, Yuzo ^[2]

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1. Miyazaki Univ. (Japan)
2. Miyazaki Medical College (Japan)

An enzyme extract prepared from ethylene-induced degreening Citrus fruits contains chlorophyll (Chl) degrading enzymes. The fate of Chl carbons during an enzymatic degradation was investigated using Chl {und a}-{sup 14}C. Accompanying the disappearance of labelled Chl {und a}, pheophorbide {und a} and pyropheophorbide {und a} appeared and accumulation of pyropheophorbide {und a} was observed. HydroxyChl {und a} was also detected, but this is thought to be an artifact during chromatography. Unlike ethylene-induced Citrus fruits (in vivo), further degradation of pyropheophorbide {und a} did not occur in vitro enzyme system. This suggests that there is a lack of enzyme(s) and/or cofactor(s) for further degradation. It is concluded that Chl {und a} degraded enzymatically by the following order: Chl {und a}, chlorophyllide {und a}, pheophorbide {und a} and pyropheophorbide {und a}.

• OSTI ID: 5644953
• Report Number(s): CONF-9007196-; CODEN: PPYSA; TRN: 91-016561
• Journal Information: Plant Physiology, Supplement; (USA), Vol. 93:1; Conference: Annual meeting of the American Society of Plant Physiologists, Indianapolis, IN (USA), 29 Jul - 2 Aug 1990; ISSN 0079-2241
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
14 SOLAR ENERGY
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CHLOROPHYLL
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CARBON 14 COMPOUNDS
CHROMATOGRAPHY
CITRUS
ENZYMES
ETHYLENE
TRACER TECHNIQUES
ALKENES
CARBON COMPOUNDS
CARBOXYLIC ACIDS
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROCARBONS
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LABELLED COMPOUNDS
MAGNOLIOPHYTA
MAGNOLIOPSIDA
METABOLISM
ORGANIC ACIDS
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PHYTOCHROMES
PIGMENTS
PLANTS
PORPHYRINS
PROTEINS
SEPARATION PROCESSES
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