Chlorophyll synthase catalyzes the final step in chlorophyll biosynthesis: the esterification of chlorophyllide with either geranylgeranyl diphosphate or phytyl diphosphate (PDP). Recent studies have pointed to the involvement of chlorophyll-linked reduction of geranylgeranyl by geranylgeranyl reductase as a major pathway for the synthesis of the PDP precursor of tocopherols. This indirect path...

The objective of this study was to determine the effects of lead (Pb) exposure on bioaccumulation, growth, and tolerance mechanisms in summer savory (Satureja hortensis L.). Plants were subjected to different levels of Pb concentrations including 0 (control), 5, 10, 25, 50 and 100 mg L-1 in growing medium. Pb treatment led to significant increase in root and shoot Pb content. Calculation of BF,...

Herbicidal Action of Aminotriazol, Wheat and Oat Seedlings, Chlorophyll, Phytol, Geranylgeraniol, Dihydrogeranylgeraniol, Tetrahydrogeranylgeraniol Treatment of wheat caryops with 3-amino-l,2,4-triazol followed by dark germination leads to phytol deficiency (based on the chlorophyll content) during the subsequent greening process in the light. The analysis of the pigment fraction reveales the p...

The positive effect of melatonin on the function of the photosynthetic apparatus is known, but little is known about the specific mechanisms of melatonin's action in plants. The influence of melatonin on chlorophyll metabolism of 24-day-old Pisum sativum L. seedlings during paraquat (PQ)-induced oxidative stress was investigated in this study. Seeds were hydro-primed with water (H), 50 and 200 ...

Anabaena variabilis, a blue-green alga lacking chlorophyll b, shows an absence of the major 22 and 24 kilodalton polypeptides which are present in the photosynthetic membranes of Chlamydomonas reinhardi and higher plants. These data are consistent with other investigations which have shown that these polypeptides are associated with chlorophyll b in the chloroplasts of higher plants, and indica...

Chlorophyll is utilized as a simple, inexpensive and environment-friendly (“green”) colorimetric indicator for nitrogen dioxide (NO2) gas. A drastic color change from green to yellow was observed when chlorophyll, either dissolved in CH2Cl2 solution or absorbed into paper, was exposed to NO2 gas. Other gases such as CO2 and SO2 did not exhibit any color change with chlorophyll. Spectroscopic an...

What is Chlorophyll? Chlorophyll, in various forms, is bound within the living cells of algae and other phytoplankton found in surface water. Chlorophyll is a key biochemical component in the molecular apparatus that is responsible for photosynthesis, the critical process in which the energy from sunlight is used to produce life-sustaining oxygen. In the photosynthetic reaction below, carbon di...

In this paper we examine time-series measurements of near-surface chlorophyll concentration from a mooring that was deployed at 80.5E on the equator in the Indian Ocean in 2010. These data reveal at least six striking spikes in chlorophyll from October through December, at approximately 2-week intervals, that coincide with the development of the fall Wyrtki jets during the transition between th...