Stran 1 iz 31 rezultatov
The potency of L-valine as an inhibitor of Zea mays acetohydroxyacid synthase (AHAS) is increased more than 8000-fold on conversion to its N-phthalyl anilide derivative which is active at 2 microM. The D-valine, alpha-aminobutyric acid, isoleucine and phenylalanine analogs are 11- to 43-fold less
The homodimeric alcohol dehydrogenase gene produce of maize (Zea mays L.) Adh1-1S1108 mutation was purified and compared with the parental Adh1-1S enzyme. The mutant alcohol dehydrogenase activity had pH optima and substrate specificity similar to those of the parental enzyme, but exhibited somewhat
Carbon-13 nuclear magnetic resonance (NMR) spectroscopy has been applied to the direct observation of acetate and pyruvate metabolism in suspension cultures of Zea mays (var Black Mexican Sweet). Growth of the corn cells in the presence of 2 millimolar [2-(13)C]acetate resulted in a rapid uptake of
The chloroplast genome contains genes for a large and probably complete set of tRNAs. These genes are unique in sharing attributes of both nuclear and bacterial tRNA genes. Two chloroplast tRNA genes from Zea mays are described here. tV-UAC, encoding a valine tRNA with the anticodon UAC, contains a
Three corn (Zea mays L.) lines resistant to imidazolinone herbicides were developed by in vitro selection and plant regeneration. For all three lines, resistance is inherited as a single semidominant allele. The resistance alleles from resistant lines XA17, XI12, and QJ22 have been crossed into the
Acetolactate synthase (EC 4.1.3.18) activity was examined in maize (Zea mays L.) endosperm and embryos as a function of kernel development. When assayed using unpurified homogenates, embryo acetolactate synthase activity appeared less sensitive to inhibition by leucine + valine and by the
Three 21-day feeding experiments were conducted to determine the sequence in which the amino acids of corn become limiting for the growth of young rats. Diets consisted of corn fortified with minerals and vitamins, and supplemented with various combinations of essential amino acids. On the basis of
Proline was the most abundant amino acid with a mean value of 186.28 μ moles/mg dry pollen. The other amino acids tested were below 33 μ moles/mg dry pollen. The mutant wx significantly increased aspartic acid, valine, histidine and an unknown but significantly decreased α aminobutyric acid. The
Pollen grains containing either the Wx, wx, Su 1, su 1, Sh 2 or sh 2 alleles were stored at 0, 1, 2, 3, 4 and 5 days at 2 °C. After each storage period, a portion of pollen from each genotype was analyzed for free amino acid content. Over all genotypes, storage significantly altered the content of
An N-balance and isotope dilution study was performed to determine the effect of lower gut N supply on N retention and CO(NH(2))(2) kinetics in growing pigs. Nine cecally cannulated and jugular-catheterized barrows (initial BW 22.4 ± 1.2 kg) were randomly assigned to 1 of 3 cecal N infusion
Aflatoxin contamination is associated with the development of aflatoxigenic fungi such as Aspergillus flavus and A. parasiticus on food grains. This study was aimed at investigating metabolites produced during fungal development on maize and their correlation with aflatoxin levels. Maize cobs were
ABSTRACT A hydrophobic 19.7-kDa amylase inhibitor (AI) was purified from corn kernels by 95% ethanol extraction and anionic exchange chromatography. The AI has an isoelectric point of 3.6 and was very stable at different pH values and high temperatures, maintaining 47.6% activity after heating to 94
The transcription factors DREB1s/CBFs specifically interact with the DRE/CRT cis-acting element (core motif: G/ACCGAC) and control the expression of many stress-inducible genes in Arabidopsis. We isolated a cDNA for a DREB1/CBF homolog, ZmDREB1A in maize using a yeast one-hybrid system. The ZmDREB1A
The maize (Zea mays L.) floury-2 (fl2) mutation is associated with a general decrease in storage protein synthesis, altered protein body morphology, and the synthesis of a novel 24-kD alpha-zein storage protein. Unlike storage proteins in normal kernels and the majority of storage proteins in fl2
This work was undertaken to investigate the concentrations of free amino acids in blood after food was withheld from growing, male Wistar rats fed cholesterol-free, low fat (1 g corn oil/100 g) diets with casein or soybean protein for 2 wk. A diet containing 22.5 or 23.5 g/100 g of soybean protein