Chlorophyll breakdown in spinach: on the structure of five nonfluorescent chlorophyll catabolites*
In extracts of senescent leaves of spinach (Spinacia oleracea), five colourless compounds with UV/Vis-characteristics of nonfluorescent chlorophyll catabolites (NCCs) were detected and tentatively named So-NCCs. The most abundant polar NCC in the leaves of this vegetable, So-NCC-2, had been isolated earlier and its constitution was determined by spectroscopic means. The catabolite So-NCC-2 was found to be an epimer of a polar NCC from barley (Hordeum vulgare), the first non-green chlorophyll catabolite from a higher plant to be structurally analyzed. Here, we report on the isolation of four additional So-NCCs from the extracts of senescent leaves of Sp. oleracea by two- (or multi-)stage chromatographic purification and on their structural characterization. The constitution of So-NCC-3 could be determined by spectroscopic analysis in combination with chemical correlation with a known NCC from Cercidiphyllum japonicum (Cj-NCC): So-NCC-3 was identified as the hydrolysis product of the methyl ester function of Cj-NCC. The less polar catabolite So-NCC-4 could be directly identified with Cj-NCC. Two further So-NCCs, So-NCC-1 and So-NCC-5, were detected only in trace amounts. Five structurally related nonfluorescent chlorophyll catabolites (So-NCCs) are thus present in senescent leaves of spinach. The structures of this set of So-NCCs indicate several peripheral refunctionalization reactions and inform on the late catabolic transformations during leaf senescence. The transformation of the tetrapyrrolic skeleton in chlorophyll catabolism in spinach and in C. japonicum is revealed to exhibit a common stereochemical pattern.
Unable to display preview. Download preview PDF.
- Bortlik K-H, Peisker C and Matile P (1990) A novel type of chlorophyll catabolite in senescent barley leaves. J Plant Physiol 136: 161–165Google Scholar
- Brown SB, Houghton JD and Hendry GAF (1991) Chlorophyll breakdown. In:Scheer H (ed) Chlorophylls, pp 465–489. CRC Press, Boca Raton, FloridaGoogle Scholar
- Kessler H, Gehrke M and Griesinger C (1988) Zweidimensionale NMR-Spektroskopie, Grundlagen und Ñbersicht über die Experimente. Angew Chem 100: 507–544; Angew Chem Int Ed Engl 27: 490-537Google Scholar
- Kräutler B, Jaun B, Amrein W, Bortlik K, Schellenberg M and Matile P (1992) Breakdown of chlorophyll: constitution of a secoporphinoid chlorophyll catabolite isolated from senescent barley leaves. Plant Physiol Biochem 30: 333–346Google Scholar
- Matile P (1987) Seneszenz bei Pflanzen und ihre Bedeutung für den Stickstoffhaushalt. Chimia 41: 376–381Google Scholar
- Mendel G (1865) Versuche über Pflanzenhybriden. Verhandlungen des Naturwissenschaftlichen Vereins, Brünn 4: 3–47Google Scholar
- Mühlecker W and Kräutler B (1996) Breakdown of chlorophyll: constitution of nonfluorescing chlorophyll-catabolites from senescent cotyledons of the dicot rape. Plant Physiol Biochem 34: 61–75Google Scholar
- Pretsch E, Bühlmann P and Affolter C (2000) Structure Determination of Organic Compounds, pp 158–160. Springer-Verlag, BerlinGoogle Scholar
- Sanders JKM and Hunter BK (1987) Modern NMR-spectroscopy. Oxford University Press, Oxford Scheer H (ed) (1991) Chlorophylls. CRC-Press, Boca Raton, FloridaGoogle Scholar
- Shioi Y, Watanabe K and Takamiya K (1996) Enzymatic conversion of pheophorbide a to a precursor of pyropheophorbide a in leaves of Chenopodium album. Plant Cell Physiol 37: 1143–1149Google Scholar
- Smith RD, Light-Wahl KJ, Winger BE and Goodlett DR (1995) Electrospray Ionization. In: Matsuo T, Caprioli RM, Gross ML and Seyama Y (eds) Biological Mass Spectrometry: Present and Future, pp 41–74. John Wiley & Sons, Chichester, UKGoogle Scholar
- Watson TR (1995) Fast atom bombardment. In: Matsuo T, Caprioli RM, Gross ML and Seyama Y (eds) Biological Mass Spectrometry: Present and Future, pp 24–40. John Wiley & Sons, Chichester, UKGoogle Scholar