The periodide method for quaternary ammonium compounds (QAC) analysis was modified to permit rapid screening of numerous replicate plant samples. This procedure provides a valuable tool for assessing salt tolerance. Aqueous plant extracts were used without further purification. Total QAC were precipitated as the periodide complexes at low pH. In neutral media, only choline periodide crystallized; other major QAC (e.g. glycinebetaine) were soluble at pH 6.8–7.0 QAC concentration was then determined spectrophotometrically.

Rapid assay for determination of water soluble quaternary ammonium compounds

http://www.jbc.org/content/249/10/3116.full.pdf

Wheat Germ Agglutinin MOLECULAR CHARACTERISTICS AND SPECIFICITY FOR SUGAR BINDING

The wheat gluten proteins correspond to the major storage proteins that are deposited in the starchy endosperm cells of the developing grain. These form a continuous proteinaceous matrix in the cells of the mature dry grain and are brought together to form a continuous viscoelastic network when flour is mixed with water to form dough. These viscoelastic properties underpin the utilization of wheat to give bread and other processed foods. One group of gluten proteins, the HMM subunits of glutenin, is particularly important in conferring high levels of elasticity (i.e. dough strength). These proteins are present in HMM polymers that are stabilized by disulphide bonds and are considered to form the ‘elastic backbone’ of gluten. However, the glutamine–rich repetitive sequences that comprise the central parts of the HMM subunits also form extensive arrays of interchain hydrogen bonds that may contribute to the elastic properties via a ‘loop and train’ mechanism. Genetic engineering can be used to manipulate the amount and composition of the HMM subunits, leading to either increased dough strength or to more drastic changes in gluten structure and properties.

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The structure and properties of gluten: an elastic protein from wheat grain

R.J. Dimler

Papers

Improved Techniques in Paper Chromatography of Carbohydrates

Starch gel electrophoresis of wheat gluten proteins with concentrated urea.

Spectrophotometric Determination of Betaines and Other Quaternary Nitrogen Compounds as Their Periodides

Characterization and properties of the phosphomannan from Hansenula hostii NRRL Y-2448.

Amide groups as interaction sites in wheat gluten proteins: Effects of amide-ester conversion