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Isocitrate lyase (EC 4.1.3.1) has been demonstrated in crude dialyzed extracts of healthy spinach (Spinacia oleracea) leaves from commercial sources and wheat (Triticum aestivum) and maize (Zea mays) leaves stored in darkness in the cold room for 1 week. The products of the reaction were identified
Improvements in preparative techniques have made it possible to isolate and purify mitochondria from the mesophyll cells of Zea mays leaves. Contamination by mitochondria from the bundle sheath cellswas insignificant. The use of a self-generatedPercoll gradient allowed the purification of washed
Using 7.5% polyacrylamide gel electrophoresis, a heterogeneity of molecular forms of "malic" enzyme (EC 1.1.1.40) in corn leaves was established. Etyolated corn sprouts contain only one component of the enzyme, while in the green leaves 3 minor components were additionally found. A possible
Nicotinamide adenine dinucleotide phosphate (NADP)-dependent glyceraldehyde-3-phosphate dehydrogenase (GPDH) (EC 1.2.1.13), a chloroplast enzyme, had low activity in etioplasts of maize leaves. A light dependent increase of enzyme activity of 7-day-old etiolated seedlings showed a lag period of
The ultrastructure of etioplasts and the acyl lipid and the fatty acid composition of sequential 2-centimeter sections cut from the base (youngest) to the top (oldest) of nonilluminated 5-day-old etiolated leaves of Zea mays L., and the acyl lipid and fatty acid composition of the etioplasts
The aim of this work was to determine the compartmentation of antioxidants between the bundle-sheath and mesophyll cells of maize (Zea mays L.) leaves. Rapid fractionation of the mesophyll compartment was used to minimize modifications in the antioxidant status and composition due to extraction
Sap extracted from attached leaves of two-to three-week-old maize plants witt the aid of a roller device was almost devoid of bundle-sheath contamination as judged by the distribution of mesophyll and bundle-sheath markers. The extraction could be done very rapidly (less than 1 s) and the extract
The incorporation of (14)C into sucrose and hexose phosphates during steady-state photosynthesis was examined in intact leaves of Zea mays L. plants. The compartmentation of sucrose synthesis between the bundle sheath and mesophyll cells was determined by the rapid fractionation of the mesophyll and
Alanine aminotransferase (AlaAT, EC 2.6.1.2) and glycine aminotransferase (GlyAT, EC 2.6.1.4), two different enzymes catalyzing transamination reactions with L-alanine as the amino-acid substrate, were examined in maize in which alanine participates substantially in nitrogen transport. Preparative
Maize (Zea mays L. cv kanaujia) plants grown with Zn [10 (control), 0.1 (low) and 20 microM (high)], were investigated for concentration of antioxidants and activities of antioxidative enzymes in leaves. Young leaves of low Zn plants developed whitish-necrotic spots. Leaves of both low and high Zn
Short incubation of [1-14C]alpha-linolenic acid with whole homogenate of leaves of corn (Zea mays L.) led to the formation of 4 major lipoxygenase products, i.e. 12-oxo-13-hydroxy-9(Z),15(Z)-octadecadienoic acid, 12-oxo-10,15(Z)-phytodienoic acid (12-oxo-PDA),
Low-temperature scanning-electron microscopy was used to study the freezing of leaves of five species that have no resistance to freezing: bean (Phaseolus vulgaris L.), tobacco (Nicotiana tabacum L.), tomato (Lycopersicon esculentum L.), cucumber (Cucumis sativus L.), and corn (Zea mays L.). In the
The aim of this work was to investigate how light regulates the activity of phosphoenolpyruvate carboxylase in vivo in C(4) plants. The properties of phosphoenolpyruvate carboxylase were investigated in extracts which were rapidly prepared (in less than 30 seconds) from darkened and illuminated
Acquisition of cell identity requires communication among neighboring cells. To dissect the genetic pathways regulating cell signaling in later leaf development, a screen was performed to identify mutants with chloroplast pigmentation sectors that violate cell lineage boundaries in maize (Zea mays)
Fatty acid synthesis was studied in successive leaf sections from the base to the tip of developing barley (Hordeum vulgare L.), maize (Zea mays L.), rye grass (Lolium perenne L.) and wheat (Triticum aestivium L.) leaves. The basal regions of the leaves had the lowest rates of fatty acid synthesis