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Previous studies indicated that the deficiency of starch-branching enzyme (SBE) Ia in the single mutant sbe1a::Mu (sbe1a) has no impact on endosperm starch structure, whereas the deficiency of SBEIIb in the ae mutant is well known to reduce the branching of starch. We hypothesized that in maize (Zea
Two major alpha-glucan phosphorylases (I and II) from leaves of the C(4) plant corn (Zea mays L.) were previously shown to be compartmented in mesophyll and bundle sheath cells, respectively (C Mateyka, C Schnarrenberger 1984 Plant Sci Lett 36: 119-123). The two enzymes were separated by
The amylose and amylopectin fractions from kernel starch synthesized shortly after exposure of intact Zea mays L. plants to (14)CO(2) had similar specific radioactivities (counts per min per mg of carbohydrate). In both fractions the radioactivity was distributed throughout the molecules. These data
Conserved isoamylase-type starch debranching enzymes (ISAs), including the catalytic ISA1 and noncatalytic ISA2, are major starch biosynthesis determinants. Arabidopsis thaliana leaves require ISA1 and ISA2 for physiological function, whereas endosperm starch is near normal with only ISA1. ISA
Among the desirable quality traits essential for commercial production of fresh or processed sweet corn, kernel sugar content is universally important. In sweet corn genotypes the primary kernel sugar is sucrose, which is elevated at the expense of starch, particularly amylopectin. Sweet corn
Sucrose synthase (SuSy) is a highly regulated cytosolic enzyme that catalyzes the conversion of sucrose and a nucleoside diphosphate into the corresponding nucleoside diphosphate glucose and fructose. In cereal endosperms, it is widely assumed that the stepwise reactions of SuSy, UDPglucose
The multiple forms of branching enzyme (BE) from developing maize (Zea mays) endosperm were purified by modification of previous procedures such that amylase activity could be eliminated completely from the BE preparation. Three distinct assays for BE activity (phosphorylase a stimulation assay, BE
To regulate the biosynthesis of maize starch, gene segment of starch branch enzyme (SBE) in maize was cloned and an expression vector of small interference RNA with the fragment of antisense gene + sense gene (pCJSBE2b, Fig.1) was constructed. The expression vector of pCJSBE2b was transformed into
In maize, opaque2 (o2) and opaque16 (o16) alleles can increase lysine content, while the waxy (wx) gene can enhance the amylopectin content of grains. In our study, o2 and o16 alleles were backcrossed into waxy maize line (wxwx). The o2o2o16o16wxwx lines had amylopectin contents similar to those of
In the present study, the effects of different irrigation levels (I50: 50%; I75: 75%; and I100: 100% of depleted water from field capacity) and nitrogen fertilizer concentrations (N1:100, N2:200 and N3:300 kg ha-1N) on starch properties (total, resistant and nonresistant starch,
The objective was to characterize thermal and viscosity properties of flour of purple maize from Argentina, and to evaluate the environmental effects on composition and flour properties. Half-sib families were selected from original germplasm and reproduced during 2014 and 2015. Chemical
This study analyzed changes in the starch structures and in vitro digestion profiles of a specific maize cultivar, Jike 728 (JK728), in Jilin, China, after 0-5 days of germination. The total starch, amylose, and amylopectin contents decreased significantly during germination. The average molecular
Mutations in the maize gene sugary2 ( su2 ) affect starch structure and its resultant physiochemical properties in useful ways, although the gene has not been characterized previously at the molecular level. This study tested the hypothesis that su2 codes for starch synthase IIa (SSIIa). Two
Starch is an agricultural raw material used in many food and industrial products. It is present in granules that vary in shape in the form of amylose and amylopectin. Starch-degrading enzymes are used on a large scale in the production of sweeteners (high fructose corn syrup) and concentrated
A methodology is developed for interpreting the molecular weight distributions of debranched amylopectin, based on techniques developed for quantitatively and qualitatively finding mechanistic information from the molecular weight distributions of synthetic polymers. If the only events occurring are