1. The human thymus-brain antigen, which corresponds to the murine (mouse or rat) Thy1 antigen complex, was isolated from brain after solubilization in deoxycholate by gel-permeation chromatography, wheat-germ-lectin affinity chromatography and ionexchange chromatography. 2. The isolated antigen is a glycoprotein displaying an apparent molecular weight of 26000-29000 in sodium dodecyl sulphate/...

After complete solubilization by the direct method, porcine pepsin was not released from AOT in isooctane reverse micelles even under aqueous-phase conditions which would not ordinarily allow uptake. Similarly, bovine chymosin, once forward-transferred at a pH below its isoelectric point, was not back-transferred into an aqueous contact phase buffered at a pH value above its isoelectric point. ...

Tobacco is widely used as a model plant for feasibility studies of recombinant protein production from transgenic plants. However, dealing with large quantities of biomass to recover recombinant proteins is a challenge for down-stream processing. In this study, the effect of isoelectric precipitation on native tobacco protein was first studied. Among the three acids studied, hydrochloric acid i...

A process based on the isoelectric solubilization/precipitation (ISP) method was developed to recover collagen from low value poultry by-products. The application of the ISP process to turkey heads generated protein isolates and an insoluble biomass that was used to extract collagen. Isolated turkey head collagen was then enzymatically hydrolyzed for different time periods using alcalase, flavo...

The amino acid composition and the physicochemical and functional properties of quinoa protein isolates were evaluated. Protein isolates were prepared from quinoa seed by alkaline solubilization (at pH 9, called Q9, and at pH 11, called Q11) followed by isoelectric precipitation and spray drying. Q9 and Q11 had high levels of essential amino acids, with high levels of lysine. Both isolates show...

In preparing intracellular microbial samples for one- or two-dimensional electrophoresis, trichloroacetic acid (TCA) precipitation is frequently used to remove interfering compounds. Solubilization of TCA precipitate typically requires the addition of a number of chaotropes or detergents, in a multistep process, that requires hours to carry out. In this study, a simple, rapid, one-step method t...

Rat brain pyruvate carboxylase was purified 2000-fold and some of its properties and kinetic parameters were investigated. The use of (NH4)2SO4 gradient solubilization on a Celite column and precipitation with polyethylene glycol permitted purification to an estimated 20% purity. Except for a few subtle kinetic differences this enzyme is indistinguishable from rat liver pyruvate carboxylase.

In this paper, crude extract of a Bowman-Birk trypsin inhibitor from soybean meal was firstly isolated by a combination of alcohol precipitation, thermal denaturation, isoelectric precipitation and acetone precipitation. Then this extract was purified by DE-52 ion exchange and affinity chromatography. The results showed that soybean Bowman-Birk trypsin inhibitor (SBBI) was purified to 50.07-fol...

PROTEINS are generally least hydrated and least soluble at their respective isoelectric points. In this connection the process of electrofocusing of proteins (Svenson, 1962; Vesterberg & Svenson, 1966) is relevant. In this method several proteins are electrophoretically propelled-through an electrophoretically established pH gradient-until they reach the particular pH regions which equal their ...