Sugar transport by maize endosperm suspension cultures. [Zea mays]

Conference · Sat Aug 01 04:00:00 EDT 1987 · Plant Physiol., Suppl.; (United States)

OSTI ID:6071294

Felker, F C; Goodwin, J C

To determine the mechanism of sugar uptake by suspension cultures derived from developing maize (Zea mays L.) endosperm, incorporation of radioactivity from /sup 14/C-sugars by the tissue in the mid-log phase of growth was examined. Among the sugars tested was l'-deoxy-l'-fluorosucrose (FS), a derivative not hydrolyzed by invertase but recognized by sucrose carriers in other systems. At 40 mM, uptake of label from FS was 23% of that from sucrose, while uptake of label from L-glucose (used as a control for medium carry-over and adsorption) was 16% of that from sucrose. Uptake of label from sucrose did not increase at concentrations above 50 mM, possibly due to a rate-limiting requirement for extracellular hydrolysis. Kinetic analysis revealed both saturable and linear components of uptake for glucose and fructose. The rate of fructose uptake exceeded that of glucose at all concentrations. Fructose uptake at 20 mM was inhibited by NaN/sub 3/, HgCl/sub 2/, dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone, and p-chloromercuribenzenesulfonic acid. Results suggest that sucrose is hydrolyzed prior to uptake, and that fructose is transported preferentially by a carrier sensitive to an external sulfhydryl group inhibitor. Metabolic activity is required for sugar uptake. The specificity of the hexose transporter is currently being investigated.

• Research Organization: Dept. of Agriculture, Peoria, IL
• OSTI ID: 6071294
• Report Number(s): CONF-8707108-
• Conference Information: Journal Name: Plant Physiol., Suppl.; (United States) Journal Volume: 83:4
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALDEHYDES
BIOCHEMICAL REACTION KINETICS
BODY
CARBOHYDRATES
CARBON 14 COMPOUNDS
CARRIERS
CEREALS
DISACCHARIDES
ENDOSPERM
FRUCTOSE
GLUCOSE
GRASS
GROWTH
HEXOSES
INHIBITION
ISOTOPE APPLICATIONS
KETONES
KINETICS
LABELLED COMPOUNDS
MAIZE
MONOSACCHARIDES
OLIGOSACCHARIDES
ORGANIC COMPOUNDS
PHYSIOLOGY
PLANT GROWTH
PLANT TISSUES
PLANTS
REACTION KINETICS
SACCHARIDES
SACCHAROSE
TISSUES
TRACER TECHNIQUES
UPTAKE