Advertisement

Topics

Large-scale isolation, fractionation, and purification of soluble starch-synthesizing enzymes: starch synthase and branching enzyme from potato tubers.

Summary of "Large-scale isolation, fractionation, and purification of soluble starch-synthesizing enzymes: starch synthase and branching enzyme from potato tubers."

Soluble starch-synthesizing enzymes, starch synthase (SSS) and starch-branching enzyme (SBE), were isolated, fractionated, and purified from white potato tubers (Solanum tuberosum) on a large scale. Five steps were used: potato tuber extract from 2 kg of peeled potatoes, two acetone precipitations, and two fractionations on a large ultrafiltration polysulfone hollow fiber 100 kDa cartridge. Three kinds of fractions were obtained: (1) mixtures of SSS and SBE; (2) SSS, free of SBE; and (3) SBE, free of SSS. Contaminating enzymes (amylase, phosphorylase, and disproportionating enzyme) and carbohydrates were absent from the 2nd acetone precipitate and from the column fractions, as judged by the Molisch test and starch triiodide test. Activity yields of 122% (300,000-400,000 units) of SSS fractions and 187% (40,000-50,000 units) of SBE fractions were routinely obtained from the cartridge. Addition of 0.04% (w/v) polyvinyl alcohol 50K and 1 mM dithiothreitol to the glycine buffer (pH 8.4) gave long-term stability and higher yields of SSS and SBE, due to activation of inactive enzymes. Several SSS and SBE fractions from the two fractionations had very high specific activities, indicating high degrees of purification. Polyacrylamide gel electrophoresis of selected SSS and SBE fractions gave two to five SSS and/or SBE activity bands, corresponding to the one to five protein bands present in the 2nd acetone precipitate.

Affiliation

Laboratory of Carbohydrate Chemistry and Enzymology, Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA.

Journal Details

This article was published in the following journal.

Name: Carbohydrate research
ISSN: 1873-426X
Pages: 1555-63

Links

DeepDyve research library

PubMed Articles [15899 Associated PubMed Articles listed on BioPortfolio]

Large scale expression and purification of secreted mouse hephaestin.

Hephaestin is a large membrane-anchored multicopper ferroxidase involved in mammalian iron metabolism. Newly absorbed dietary iron is exported across the enterocyte basolateral membrane by the ferrous...

Electroconvulsive Seizures in Rats and Fractionation of Their Hippocampi to Examine Seizure-induced Changes in Postsynaptic Density Proteins.

Electroconvulsive seizure (ECS) is an experimental animal model of electroconvulsive therapy, the most effective treatment for severe depression. ECS induces generalized tonic-clonic seizures with low...

A rapid, efficient, and economic device and method for the isolation and purification of mouse islet cells.

Rapid, efficient, and economic method for the isolation and purification of islets has been pursued by numerous islet-related researchers. In this study, we compared the advantages and disadvantages o...

New Interface for Purification of Proteins: 1D TiO2 Nanotubes Decorated by Fe3O4 nanoparticles.

In this work, a high surface area interface, based on anodic 1D TiO2 nanotubes homogenously decorated by Fe3O4 nanoparticles is reported for the first time for an unprecedented purification of His-tag...

Facile Purification of Milligram to Gram Quantities of Condensed Tannins According to Mean Degree of Polymerization and Flavan-3-ol Subunit Composition.

Unambiguous investigation of condensed tannin (CT) structure-activity relationships in biological systems requires well-characterized, high-purity CTs. Sephadex LH-20 and Toyopearl HW-50F resins were ...

Clinical Trials [3189 Associated Clinical Trials listed on BioPortfolio]

Standard Process 21 Day Purification Program Project

To determine the effects of a commercially available dietary modification plus nutritional supplement regimen, the Standard Process 21 day Purification Program (SPPP), on serum lipids, C-r...

Resistant Starch on Glucose and Insulin Sensitivity in Individuals With Type 2 Diabetes

This study will test the effects of resistant starch type 4 on blood sugar and hunger in adults with Type 2 diabetes.

Effects of Hi-maize Resistant Starch on Insulin Sensitivity

The purpose of this study is to determine the effects of a dietary fiber, resistant starch, on insulin sensitivity. Low insulin sensitivity is a risk factor for some diseases including ty...

Altered and Conventional Fractionated Radiotherapy in Patients With Head and Neck Cancer

The aim of our study was to evaluate the value of two different altered fractionation schedules – hyperfractionation and accelerated fractionation with concomitant boost – in compariso...

Starch or Saline After Cardiac Surgery

When people undergo major surgery, they require intravenous supplementation of fluids for a number of reasons: - to compensate for no oral intake - to support blood pressure ...

Medical and Biotech [MESH] Definitions

The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.

Electrophoresis in which a starch gel (a mixture of amylose and amylopectin) is used as the diffusion medium.

A scale comprising 18 symptom constructs chosen to represent relatively independent dimensions of manifest psychopathology. The initial intended use was to provide more efficient assessment of treatment response in clinical psychopharmacology research; however, the scale was readily adapted to other uses. (From Hersen, M. and Bellack, A.S., Dictionary of Behavioral Assessment Techniques, p. 87)

The large scale production of pharmaceutically important and commercially valuable RECOMBINANT PROTEINS.

A subjective psychometric response scale used to measure distinct behavioral or physiological phenomena based on linear numerical gradient or yes/no alternatives.

Quick Search
Advertisement
 


DeepDyve research library

Relevant Topics

Enzymes
Enzymes are proteins that catalyze (i.e., increase the rates of) chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical re...

Nutrition
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...


Searches Linking to this Article