Chlorophylls synthesis

U. Johanningmeier, S. H. Howell (1984) Regulation of light-harvesting chlorophyll-binding protein mRNA accumulation in Chlamydomonas reinhardtii. Possible involvement of chlorophyll synthesis precursors. J. Biol. Chem., 259 13541-13549... 

Dale,M. F. B., Griffiths, D. W., Bain, H., Goodman, B. A. (1997). The Effect ofGamma Irradiation on Glyeoalkaloid and Chlorophyll Synthesis in Seven Potato Cultivars. J Sci Food Agric., 75, 141-147. 

A welcome side effect of treating fungi (e.g. peronospora plasmopara viticola) with iron blue is the fertilizing of vines in soils that give rise to chlorosis. Leaf color is intensified, ageing of the leaves is retarded, and wood quality ( ripeness ) is also improved [3.196]—[3.198]. Iron is necessary for chlorophyll synthesis, which improves grape quality and yield. Other iron salts do not have this effect [3.197]. 

Chlorophyll. The pathway of chlorophyll synthesis has been elucidated through biochemical genetic studies of Rhodobacter spheroides y]7 118a which produces bacteriochlorophyll, from studies of cyanobacteria,419 420 and from investigations of green algae and higher plants,421 which make chlorophyll a. The first step in the conversion of protoporphyrin IX into chlorophyll is the insertion of Mg2+ (Fig. 24-23, step a). 

COPPER (In Biological Systems), The activity of copper in plant metabolism manifests itself in two forms 11) synthesis of chlorophyll, and 12) activity of enzymes. In leaves, most of the copper occurs in close association with chlorophyll, but little is known of ns rale in chlorophyll synthesis, other than the presence of cupper is required. Copper is a definite constituent of several enzymes catalyzing oxidation-reduction reactions (oxidases), in which the activity is believed to be due to the shuttling of copper between the +1 and +2 oxidalicm states,... 

Biosynthesis of The starting point for heme and chlorophyll synthesis is aminolaevulinic acid... 

Gough. Genetic regulation of chlorophyll synthesis analyzed with mutants in barley. Science 184 800-802, 1974. 

More specifically, compounds like podolactone A (Fig. 10.1) inhibit proton efflux from plant cells induced by fusicoccin, without affecting ATP levels.42 The related compound, podolactone E is a strong inhibitor of 6-aminolevulinic acid and chlorophyll synthesis.34 The authors concluded that this was caused by suppression of synthesis of proteins needed in the porphyrin pathway because podolactones also inhibited gibberellic acid-induced a-amylase synthesis in barley embryos. The molecular target site(s) of this class of terpenoid phytotoxins remains to be determined. 

Role in chlorophyll synthesis, enzymes, oxygen transfer... 

Falbel T, Meehl JB and Staehelin LA. (1996). Severity of mutant phenotype in a series of chlorophyll-deficient wheat mutants depends on light intensity and the severity of the block in chlorophyll synthesis. Plant Physiol. 112, 821-832. 

Maize is a hot-weather crop. Table II shows that low temperature depressed the synthesis of chlorophyll in etiolated leaves exposed to light, and brassinolide relaxed the depression of chlorophyll synthesis, especially at low temperature. For example, the chlorophyll content of the control at 18 ° C was 68% less than that of control at 30 ° C. However, the chlorophyll content of brassinolide-treated leaves at 18 ° C was only 36-44.5% less than that of brassinolide-treated leaves at 30 ° C. A... 

Iron-containing proteins are essential for photosynthetic and respiratory electron transport. Chlorophyll synthesis is also dependent on iron, and chlorophyll content is diminished under iron limitation. Requirements for iron are also influenced by the nitrogen substrate used to support growth. Both nitrate and nitrite reductases contain iron in their catalytical centres. Iron efficiency models (Raven, 1988) and culture studies (Maldonado Price, 1999) show that cells using nitrate require 60-70% more cellular iron to support a given growth rate than those assimilating ammonia. 

Rudiger W (2003) The Last Step of Chlorophyll Synthesis. In Kadish KM, Smith KM, Guilard R (eds.) The Porphyrin Handbook, Vol. 13, p. 71. Elsevier Science, Amsterdam... 

Thylakoid membrane absorption of light by chlorophyll, synthesis of ATP -, NADPH, and electron transport... 

In plants treated with borates phytotoxic symptoms develop slowly, the main symptoms being withering and scorching. The biochemical mode of action of borates is unknown. According to the investigations of Brebion et al. (1954), sodium tetraborate considerably inhibits chlorophyll synthesis in young wheat plants, indicating one possible cause of its herbicidal activity. 

Used pre- and postemergence, dichlormate kills young sensitive seedlings. After treatment, sensitive weeds show on sprouting extreme chlorotic symptoms and wither because of the inhibition of chlorophyll synthesis. 

---