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C W Wrigley

Publications and source records attributed to C W Wrigley.

At least 19 recordsLinked to original sources
PubMed2001

The wheat-grain proteome as a basis for more efficient cultivar identification.

The wheat-grain proteome was investigated, as a basis for devising more efficient methods of cultivar identification or discrimination. Australian wheats (Halberd, Cranbrook, CD87 and Katepwa) were used as the basis of this study. These cultivars were selected on the basis of differences in the quality types represented, in terms of dough-processing attributes that can suit one cultivar better than another for specific types of industrial utilisation. Total wheat endosperm (flour) protein extracts were prepared from mature wheat for two-dimensional electrophoresis, across both acidic (pH 4-7) and basic (pH 6-11) pH ranges. Three particular regions of the proteome maps were chosen for close comparison, involving two sets of gluten proteins and a nongluten protein region (involving small heat shock proteins), based on previous protein characterisation. Differences in the nongluten protein regions (heat shock proteins and other unidentified polypeptides) are of particular interest as being possible targets for use in developing new approaches to cultivar discrimination, such as the development of simple immunoassays.

Electrophoresis, Gel, Two-Dimensional↗
PubMed1996

Distinction between genotypes of Lupinus species by sodium dodecyl sulphate-gel electrophoresis and by capillary electrophoresis.

Effective distinction was achieved among a wide range of lupin grain samples by either sodium dodecyl sulphate (SDS)-gel electrophoresis or capillary electrophoresis, based on grain-protein composition. Capillary electrophoresis was faster (< 1 h) and provided slightly greater distinction between the samples. On the other hand, SDS-gel electrophoresis could provide a greater through-put of samples in a 24 h period. Either technique could be used successfully to distinguish between lupin species and cultivars for taxonomic analysis or seed identification.

Electrophoresis, Capillary↗
PubMed1996

Preparative affinity membrane electrophoresis.

Using the patented Gradiflow system in conjunction with newly developed affinity membranes, the suitability of an electrokinetic technique for affinity fractionation was investigated. Blue dextran incorporated into an affinity membrane was used to deplete a solution of horse serum of albumin, with the result that a majority of serum proteins were enriched tenfold relative to albumin. The technique, when fully developed, would offer some advantages over affinity chromatography, since to a degree it is possible to control which components of the sample are presented to the affinity matrix. Furthermore, the technique would extend the capabilities of the already multifunctional Gradiflow system.

Blood Proteins↗
PubMed1994

Multifunctional apparatus for electrokinetic processing of proteins.

New equipment (the "Gradiflow") has been designed and constructed to provide efficient large-scale preparative fractionation of macromolecules, based on charge and/or size differences, as well as the concentration of macromolecules and electrodialysis. Examples of its capability are the separation of a mixture of haemoglobin (50 mg) from bovine serum albumin (50 mg) within 15 min (based on charge differences at pH 6.8), the purification of phycoerythrin from a crude extract on the basis of size, and the fractionation of serum proteins into two discrete size classes.

Animals↗
PubMed1993

Our obsession with high resolution in gel electrophoresis: does it necessarily give the right answer?

Poor resolution of protein zones in an electrophoretic pattern may not necessarily be the result of poor technique. The example is given of the 'streak material', extracted from wheat flour, now recognised to be aggregated subunits of glutenin. The size distribution of the aggregated glutenin 'streak' is the key to elucidating the functional properties of wheaten dough. A stepped-layer gel technique has been devised to quantitate the proportions of aggregated glutenin in specific size groupings.

Electrophoresis↗
PubMed1992

Rapid and automated characterisation of seed genotype using Micrograd electrophoresis and pattern-matching software.

New precast microgels are described for use in quickly identifying seed of cereal varieties by determining protein composition within an hour. For example, gliadin proteins are extracted from crushed wheat grain, wheatmeal or flour with ethylene glycol (centrifugation not necessary) and 5 microliters extract is applied to a Micrograd gel (3-15% gel gradient) for ten minutes' electrophoresis at 300 volts in sodium lactate buffer (pH 3.1). Alternatively, precast gels are available for SDS gel electrophoresis for examining a different aspect of grain composition as a means of identification. To further expedite identification, software packages have been developed to match the protein pattern for an unknown sample against those of authentic samples, thus to provide quick and definite identity, based on electrophoretic banding, densitometer scan, HPLC profile, multiple antibody reaction or RFLP pattern (PatMatch program). Furthermore, the program WhatWheat offers advice on the best combination of methods to use for a specific task of identification.

Automation↗
PubMed1992

Rapid (ten-minute) pore-gradient electrophoresis of proteins and peptides in Micrograd gels.

Precast gradient gels of short migration length (25 mm) have been developed to provide rapid electrophoretic separation without loss of resolution. These Micrograd gels have been prepared in gel ranges (conventional and unique) to match pore-gradient electrophoresis conditions to proteins/peptides ranging in size from several hundreds to millions. The Hylinx Micrograd gel combines an extreme gel range (6 to 48% polyacrylamide) with a novel crosslinker to provide sieving of polypeptides, and pore-limit electrophoresis of the smallest proteins (e.g. insulin monomer). All gel ranges (such as 3 to 30%) provide zone sharpening in routine analysis of conventional protein mixtures (e.g. serum) within 10 min electrophoresis at 200 to 300 volts. The gels are thin (1 mm) and thus stain quickly, but the gel cassette is of conventional overall width (83 mm), thus fitting many apparatus designs and accommodating 12 samples. The gels are finding valuable use in screening applications, requiring the electrophoretic analysis of many samples, and in cases where a rapid answer is needed, such as monitoring protein purification. The gels have proved particularly useful, in-house, for the latter application in developing Gradipore's new large-scale preparative electrophoresis system, the Gradiflow.

Electrophoresis, Polyacrylamide Gel↗
PubMed1991

A rapid (less than 10 minute) electrophoresis method for identification of wheat varieties.

Conventional procedures for electrophoretic identification of grain samples according to variety are too slow to permit checking at the time of delivery. The method described permits electrophoretic identification within an hour. It involves extraction of gliadin proteins from crushed grain with 6% urea solution or ethylene glycol, cathodic electrophoresis for 9 min at 300 V in a Micrograd gel (MG 315 from Gradipore Ltd, Sydney, Australia) using sodium lactate buffer (pH 3.1), and staining in Gradipore (at about 50 degrees C). Distinction between a set of Australian varieties was similar to that obtainable with the Australian Standard Procedure.

Electrophoresis, Polyacrylamide Gel↗
PubMed1985

A comparison of the binding of IgE in the sera of patients with bakers' asthma to soluble and insoluble wheat-grain proteins.

The IgE-binding proteins from flour, associated with bakers' asthma, have been reassessed by use of a modified RAST suitable for both soluble and insoluble proteins. Nitrocellulose sheet was used for preparing RAST discs, and seven different solvents were compared for their suitability in preparing discs. Dilute alkali (1% potassium hydroxide) was chosen as the best solvent for disc preparation, and its use was compared with that of water as solvent. RAST analyses of sera from 24 allergic bakers demonstrated that the albumin fraction of flour is clearly allergenic (as found in previous studies), but in addition, major IgE-binding proteins were found in the other three fractions (globulin, gliadin, and glutenin) when potassium hydroxide was the solvent (but not with water). We conclude that current RAST procedures, which favor water-soluble allergens, are inadequate because they do not satisfactorily test for water-insoluble allergens.

Albumins↗
PubMed1985

Identification of species of fish by gradient-gel electrophoresis.

An electrophoretic method is described for distinguishing between fish fillets according to their protein composition. Thaw fluid (4 microL) was applied to one of 14 sample positions of a precast gel, containing a gradient of polyacrylamide of either 2.5 to 27% or 3 to 40%. All reagents and gels are commercially available in ready-to-use form. Either gel provided a distinction between any of the 42 fish types, but the 3 to 40% gel gave better identification because of its superior molecular-sieving properties. Reproducible electrophoretic patterns were obtained for different samples of the same fish type, but small differences were shown for fish of widely different origin, for example Australian and New Zealand ling.

Animals↗
PubMed1984

Allergen discs prepared from nitrocellulose: detection of IgE binding to soluble and insoluble allergens.

Nitrocellulose discs, 6 mm in diameter, are suggested as an alternative to cyanogen bromide-activated paper for the coupling of allergens in radio- or enzyme-linked assays to estimate allergen-specific IgE in serum. The preparation of allergen discs with nitrocellulose is simple, involving 3 steps: (a) drying allergen extract onto disc, (b) soaking discs in a 3% solution of bovine serum albumin, and (c) washing out the buffer. Very similar results (r = 0.94) were obtained using either paper or nitrocellulose discs for radioallergosorbent testing of sera from 15 bakers using allergens from mites, ryegrass pollen or wheat grain. The amount of protein (as radiolabelled albumin) actually bound to either type of disc or microtitre trays was similar, and low (5% of the protein applied for each media). However, when the protein was applied to nitrocellulose in 1% KOH up to 70% of it was bound. This solvent permitted better evaluation of IgE binding to insoluble allergens such as glutenin, which proved to be the most allergenic wheat-grain fraction tested by this method for a group of 9 bakers.

Allergens↗
PubMed1984

Relationships between plants relevant to allergy.

This article gives background information on the taxonomic relationships between plants, for clinicians, patients and students of allergy. A list is provided of plants considered potentially allergenic either by inhalation of pollen or by ingestion of grain products. Distributions in Australia of plant species important in assessing pollen-related allergy, and the range of foodstuffs that contain cereal-grain protein, are also indicated. Particular emphasis is placed on the grasses because of their importance as producers of both grain and pollen.

Cross Reactions↗
PubMed1984

Simultaneous detection of IgE binding to several allergens using a nitrocellulose 'polydisc'.

The use of nitrocellulose for allergen disc preparation permits several different allergens to be applied as separate spots to the same disc for simultaneous evaluation with one serum sample (50 microliter). To achieve this, an immunological application method involving anti-human IgE and the peroxidase-anti-peroxidase procedure must be used with a substrate that produces an insoluble product. The suitability of the polydiscs for routine clinical evaluation of several allergens at once was demonstrated by testing the sera of seven allergic bakers with discs containing extracts of flour or pollen from wheat, cereal rye, or rye grass.

Allergens↗
PubMed1984

The diversity of allergens involved in bakers' asthma.

Sera from 35 individuals with suspected allergies to inhaled flour were screened for the presence of immunoglobulin E (IgE) specific for wheat-flour proteins. Sera from nine asthmatic bakers with high wheat RAST scores were selected for further study with the aim of purifying the allergen(s) involved in bakers' asthma and related conditions. However, each of the different techniques applied--ion exchange chromatography, preparative isoelectric focusing and the electrophoretic transfer, or 'Western blotting' technique, showed that serum IgE from different individuals have markedly different specificities and bind to numerous wheat proteins. When three purified wheat proteins were tested--wheat germ agglutinin; a fraction purified using a concanavalin-A affinity column and a putative trypsin inhibitor--all were identified as allergens for some but not all of the allergic bakers.

Allergens↗
PubMed1983

Electrophoresis of small proteins in highly concentrated and crosslinked polyacrylamide gradient gels.

A high concentration (40%) of acrylamide plus N,N'-methylenebisacrylamide combined with a high level of crosslinking (12.5%) yielded clear gels capable of restricting the passage of small proteins. This gel composition was chosen in preference to other combinations, in particular those producing opaque gels which have larger pore sizes and which provide a reduced sieving effect. Gradient gels were prepared in which the gel concentration rose from 3 to 40% and the degree of crosslinking increased from 4 to 12.5%. Such gels were suitable for fractionating crude, unreduced, and uncharacterized extracts containing proteins ranging in molecular size from 10,000 to several million daltons under conditions where all proteins are retained on the gel even after prolonged electrophoresis. The gels yielded zones which were of improved sharpness and resolution compared with gels of lower concentration and degree of crosslinking, and can be used to provide an estimate of molecular size. Examples of the use of HX gradient gels included both anodic and cathodic electrophoresis at pH 8.3 and 3.1, respectively, of serum and cereal-grain proteins and a partial enzymic hydrolysate of serum albumin.

Acrylamides↗
PubMed1982

Detection of IgE- and IgG-binding proteins after electrophoretic transfer from polyacrylamide gels.

An electrophoretic technique for transferring proteins to a nitrocellulose membrane has been applied to proteins separated in polyacrylamide gels by isoelectric focusing, and gradient, SDS and 2-dimensional electrophoresis. Allergenic proteins were then identified by successive incubation of the transfer membrane with serum from allergic individuals and with 125I-labelled anti-human IgE, followed by autoradiography. Alternatively, IgG binding proteins were detected using 125I-labelled protein A. The application of these methods was illustrated with cereal grain proteins and sera from individuals with bakers' asthma and coeliac disease. This approach allowed the easy comparison of allergens important for different patients in a single source, and of allergens present in different but cross-reacting sources.

Allergens↗