Pyrazolinyl and cyclopropyl derivatives of protoporphyrin IX and chlorins related to chlorophyll a

Pecan is one of the most famous nut species in the world. The phenotype of mutants with albino leaves was found in the process of seeding pecan, providing ideal material for the study of the molecular mechanisms leading to the chlorina phenotype in plants. Both chlorophyll a and chlorophyll b contents in albino leaves (ALs) were significantly lower than those in green leaves (GLs). A total of 5171 differentially expression genes (DEGs) were identified in the comparison of ALs vs. GLs using high-throughput transcriptome sequencing; 2216 DEGs (42.85%) were upregulated and 2955 DEGs (57.15%) were downregulated. The expressions of genes related to chlorophyll biosynthesis (HEMA1, encoding glutamyl-tRNA reductase; ChlH, encoding Mg-protoporphyrin IX chelatase (Mg-chelatase) H subunit; CRD, encoding Mg-protoporphyrin IX monomethylester cyclase; POR, encoding protochlorophyllide reductase) in ALs were significantly lower than those in GLs. However, the expressions of genes related to chlorophyll degradation (PAO, encoding pheophorbide a oxygenase) in ALs were significantly higher than those in GLs, indicating that disturbance of chlorophyll a biosynthesis and intensification of chlorophyll degradation lead to the absence of chlorophyll in ALs of pecan. A total of 72 DEGs associated with photosynthesis pathway were identified in ALs compared to GLs, including photosystem I (15), photosystem II (19), cytochrome b6-f complex (3), photosynthetic electron transport (6), F-type ATPase (7), and photosynthesis-antenna proteins (22). Moreover, almost all the genes (68) mapped in the photosynthesis pathway showed decreased expression in ALs compared to GLs, declaring that the photosynthetic system embedded within the thylakoid membrane of chloroplast was disturbed in ALs of pecan. This study provides a theoretical basis for elucidating the molecular mechanism underlying the phenotype of chlorina seedlings of pecan.

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Molecular Aspects of Herbicide Action on Protoporphyrinogen Oxidase

Zeitschrift für Naturforschung C ◽

10.1515/znc-1993-3-434 ◽

1993 ◽

Vol 48 (3-4) ◽

pp. 326-333 ◽

Cited By ~ 5

Author(s):

Beate Nicolaus ◽

Gerhard Sandmann ◽

Peter Böger

Keyword(s):

Diphenyl Ether ◽

Protoporphyrin Ix ◽

Protoporphyrinogen Oxidase ◽

Relative Specificity ◽

Oxidase Inhibition ◽

Dilution Experiments ◽

Membrane Bound ◽

The Common ◽

Molecular Aspects ◽

Derivatives Of

Abstract Protoporphyrinogen oxidase, the last enzyme of the common tetrapyrrole biosynthetic pathway, is inhibited by several peroxidizing compounds resulting in accumulation of photodynamic tetrapyrroles, mainly protoporphyrin IX. The inhibition characteristics of two chemically unrelated compounds were studied using membrane bound protoporphyrinogen oxidase from corn etioplasts. As shown by Lineweaver-Burk-analysis, the inhibition of enzyme activity by the diphenyl ether oxyfluorfen and the cyclic imide MCI 15 are competitive with respect to the substrate. The competitive interaction of protoporphyrinogen and the two chemically unrelated inhibitors indicate a relative specificity of the binding site. The reversibility of oxyfluorfen inhibition was evaluated by dilution experiments and was shown to be independent of the presence of DTT. The analysis of structure-activity-relationship on protoporphyrinogen oxidase inhibition was investigated with para-substituted derivatives of phenyl-3,4,5,6-tetrahydro-phthalimides. The results obtained by QSAR -calculation yielded a good correlation of the inhibitory activity determined by the lipophilicity of the para-substituent. These data point to one binding region of the inhibitors within a lipophilic environment associated with the active center of the enzyme.

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The chemistry of pyrrolic compounds. XIV. meso-Hydroxyprotoporphyrin IX and its derivatives

Australian Journal of Chemistry ◽

10.1071/ch9702477 ◽

1970 ◽

Vol 23 (12) ◽

pp. 2477 ◽

Cited By ~ 13

Author(s):

PS Clezy ◽

AJ Liepa

Keyword(s):

Protoporphyrin Ix ◽

Bile Pigment ◽

General Properties ◽

Biliverdin Ix ◽

Hydrolysis Of ◽

Derivatives Of ◽

Benzoate Derivatives

The preparation of the acetate and benzoate derivatives of �-hydroxy-protoporphyrin IX is described and the hydrolysis of these enolic esters examined. The general properties of these porphyrins are discussed together with the oxidation of this system to a bile pigment identical with biliverdin IX�: with regard to spectroscopic and chromatographic characteristics.

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Identification of Novel Sulfur-Containing Derivatives of Chlorophyll a in a Recent Sediment.

ChemInform ◽

10.1002/chin.200326188 ◽

2003 ◽

Vol 34 (26) ◽

Author(s):

Angela H. Squier ◽

Dominic A. Hodgson ◽

Brendan J. Keely

Keyword(s):

Chlorophyll A ◽

Recent Sediment ◽

Derivatives Of ◽

Sulfur Containing

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Bile pigment synthesis in plants. Incorporation of haem into phycocyanobilin and phycobiliproteins in Cyanidium caldarium

Biochemical Journal ◽

10.1042/bj1940137 ◽

1981 ◽

Vol 194 (1) ◽

pp. 137-147 ◽

Cited By ~ 35

Author(s):

S B Brown ◽

J A Holroyd ◽

R F Troxler ◽

G D Offner

Keyword(s):

Chlorophyll A ◽

Protoporphyrin Ix ◽

Bile Pigment ◽

Cyanidium Caldarium ◽

Pigment Synthesis ◽

14C Labelling

A procedure was developed whereby haem was taken up by dark-grown cells of the unicellular rhodophyte Cyanidium caldarium. These cells were subsequently incubated either in the dark with 5-aminolaevulinate, which results in excretion of phycocyanobilin into the suspending medium or incubated in the light, which results in synthesis and accumulation of phycocyanin and chlorophyll a within the cells. Phycocyanobilin was isolated from phycocyanin by cleavage from apoprotein in methanol. Phycocyanobilin prepared from phycocyanin or excreted from cells given 5-aminolaevulinate was methylated and purified by t.l.c. By using 14C labelling either in the haem or in 5-aminolaevulinate administered, haem incorporation into phycocyanobilin was demonstrated in both dark and light systems. Since chlorophyll a synthesized in the light in the presence of labelled haem contained no radioactivity, it was clear that haem was directly incorporated into phycocyanobilin and not first converted into protoporphyrin IX. These results clearly demonstrate phycocyanobilin synthesis via haem and not via magnesium protoporphyrin IX as has also been postulated.

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Chlorophyll a biosynthesis

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1976.0010 ◽

1976 ◽

Vol 273 (924) ◽

pp. 207-225 ◽

Cited By ~ 10

Keyword(s):

Chlorophyll A ◽

Chlorophyll Biosynthesis ◽

Protoporphyrin Ix ◽

Chlorophyll Synthesis ◽

Synthesis Reaction ◽

Etiolated Leaves ◽

Regulatory Aspects ◽

Vinyl Group ◽

Chlorophyll A Biosynthesis ◽

Monomethyl Ester

Protoporphyrin IX is believed to be an intermediate common to both haem and chlorophyll biosynthesis. The pathway specific to chlorophyll starts with magnesium protoporphyrin and its monomethyl ester. Two routes have been proposed for conversion of the latter compound to protochlorophyllide: A, formation of the isocyclic ring followed by reduction of the 4-vinyl group, or B, reduction of the 4-vinyl group followed by formation of the isocyclic ring. Membranes prepared from isolated barley etioplasts are found to convert magnesium 2,4-divinylphaeoporphyrin a 5 monomethyl ester to chlorophyllide a at a rate equal to that of chlorophyll synthesis in intact leaves: this result supports route A. NADPH is necessary to maintain the two successive reductive steps: reduction of the 4-vinyl group and then the photoreduction of ring IV to yield chlorophyllide. The prohaem content of etiolated leaves does not increase during the phase of active chlorophyll synthesis although evidence is presented that suggests that the ALA synthesis reaction that regulates chlorophyll synthesis is common to both pathways. This and other regulatory aspects are discussed.

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