The reaction of several plant chlorophyll-protein complexes with NaBH, has been studied by absorption spectroscopy. In all the complexes studied, chlorophyll b is more reactive than Chl a , due to preferential reaction of its formyl substituent at C-7. The complexes also show large variations in reactivity towards NaBH, and the order of reactivity is: LHCI > PSI1 complex > LHCII > PSI > P700 (i...

background & aim: the pigments inside the leaf chloroplasts receive sunlight energy and transport it to photosynthesis reaction center. the most important of these pigments is chlorophyll. in this study, the pigments existence in medicinal plant, sumac (rhus coriaria l.), was investigated at biotechnology laboratory, isfahan university of technology. experimental: experiments were performed...

The content of individual chlorophyll and carotenoid pigments is determined in three spinach varieties (Lorelei, Springfield, and Ballet) after processing. Raw spinach and spinach that is steam-blanched for 3, 9, or 15 min is stored frozen at -24 degrees C for 6 months. In addition, spinach is air-dried at 75 degrees C, packed in atmospheric air or nitrogen, and stored at ambient temperature fo...

Tonnage (T), Simmonds (S) avocado trees, and TxS crosses were evaluated for differences in chlorophyll content and maximal quantum yield of photosystem II in sun and shade-type leaves. Total chlorophyll content by area (Chl a+bar) ranged from 984 mg m in TxS240 to 4320 mg m in Simmonds. Chlorophyll a/b ratio (Chl a/b) ranged from 9.8 to 5.5 in TxS238 and TxS243, respectively. Tonnage and Simmon...

Chlorophyll b is an ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. Its biosynthesis plays a key role in the adaptation to various light environments. We isolated six chlorophyll b-less mutants by insertional mutagenesis by using the nitrate reductase or argininosuccinate lyase genes as tags and examined the rearrangement of mutant genomes. We found that an overla...

The light harvesting like protein 3 (LIL 3) from higher plants, has been linked to functions in chlorophyll and tocopherol biosynthesis, photo-protection and chlorophyll transfer. However, the binding of chlorophyll to LIL3 is unclear. We present a reconstitution protocol for chlorophyll binding to LIL3 in DDM micelles. It is shown in the absence of lipids and carotenoids that reconstitution of...

The partition of phylloquinone (vitamin K J, of chlorophylls a and b and of the two main carotenoids, /?-carotene and lutein, in subthylakoid particles (digitonin treatment) and chlorophyll protein complexes (sodium dodecylsulfate polyamide-gel electrophoresis) isolated from tobacco chloroplasts (Nicotiana tabacum L.) is described. 1. The “light particle” fractions (S 90000, S 150000) of digito...

The mechanism of formation of the formyl group of chlorophyll b has long been obscure but, in this paper, the origin of the 7-formyl-group oxygen of chlorophyll b in higher plants was determined by greening etiolated maize leaves, excised from dark-grown plants, by illumination under white light in the presence of either H2(18)O or 18O2 and examining the newly synthesized chlorophylls by mass s...

Plants acclimate to variations in light intensity by changing the antenna size of photosystems. This acclimation allows them to undergo efficient photosynthesis and creates a protective strategy to minimize photodamage. Chlorophyll b synthesis by chlorophyllide a oxygenase (CAO) is a key regulatory step in the control of antenna size. Recently, we found that higher plant CAOs consist of three d...