Chlorophyll synthesis and degradation were analyzed in the cyanobacterium Synechocystis sp. PCC 6803 by incubating cells in the presence of 13C-labeled glucose or 15N-containing salts. Upon mass spectral analysis of chlorophyll isolated from cells grown in the presence of 13C-glucose for different time periods, four chlorophyll pools were detected that differed markedly in the amount of 13C inc...

An in vitro translation system using lysed etioplasts was developed to test if the accumulation of plastid-encoded chlorophyll a apoproteins is dependent on the de novo synthesis of chlorophyll a. The P700 apoproteins, CP47 and CP43, were not radiolabeled in pulsechase translation assays employing lysed etioplasts in the absence of added chlorophyll precursors. When chlorophyllide a plus phytyl...

Developing chloroplasts were incubated under conditions previously shown to induce protochlorophyll and chlorophyll biosynthesis, as well as chloroplast maintenance and partial differentiation in vitro. In the presence of air, delta-aminolevulinic acid, coenzyme A, glutathione, potassium phosphate, methyl alcohol, magnesium, nicotinamide adenine dinucleotide, and adenosine triphosphate, microgr...

Although it’s not very well known in the world of nutrition, chlorophyll couldn’t be more important in the world of biology and plants. All green plants contain at least one type of chlorophyll (chlorophyll a). Plants that evolved at a later point in history (“higher plants”) also contain a second type of chlorophyll (chlorophyll b). There are also forms of chlorophyll called chlorophyll c1, c2...

Photosynthetic pigment composition was studied in batch cultures of Heterocapsa sp. and Olisthodiscus luteus growing exponentially in a 12:12 light:dark cycle. Both species divided in the dark. The synthesis of pigments was continuous for both species. However for chlorophyll c and peridinin, in Heterocapsa sp., and chlorophyll c and fucoxanthin, in 0. luteus, (pigments belonging to light harve...

Impact of the wheat stem sawßy, Cephus cinctus Norton (Hymenoptera: Cephidae), feeding injury on chlorophyll content and photosystem II (PSII) photochemistry in heads of wheat, TriticumaestivumL., at the grain-Þlling developmental stagewas evaluated by biochemically assessing the total chlorophyll, chlorophyll a (Chla), chlorophyll b (Chlb), chlorophyll a/b ratio (Chla/b), and carotenoid concen...

The organization of pigment molecules in photosystems is strictly determined. The peripheral antennae have both chlorophyll a and b, but the core antennae consist of only chlorophyll a in green plants. Furthermore, according to the recent model obtained from the crystal structure of light-harvesting chlorophyll a/b-protein complexes II (LHCII), individual chlorophyll-binding sites are occupied ...

Trimeric (bT) and monomeric (bM) light-harvesting complex II (LHCII) with a chlorophyll a/b ratio of 0.03 were reconstituted from the apoprotein overexpressed in Escherichia coli. Chlorophyll/xanthophyll and chlorophyll/protein ratios of bT complexes and 'native' LHCII are rather similar, namely, 0.28 vs 0. 27 and 10.5 +/- 1.5 vs 12, respectively, indicating the replacement of most chlorophyll ...

Constant reduction of stratospheric ozone layer and the increase of ultraviolet radiation intensity were observed in last twenty years of the 20th century. Four tree species; Acacia amplicepsis, Acacia gerradii, Casuarina glauca and Eucalyptus intertexta grown in Experimental station of Food and Agriculture Sciences Collage, King Saud University were used to study the impact of UV-C on potentia...