Search results

Search:
in the keywords: THERAPEUTIC EFFECT

Sort By:

Limit search:

Yeast antimicrobial proteins

100%

Salek A. T.

Biotechnologia

2001

issue 4

135-162

Many yeasts secrete proteins which are toxic for pathogenic and non-pathogenic microorganisms. These toxins, mostly glycoproteins, consist of membrane-binding subunits which interact with carbohydrates (e.g. 1,6--D-glucan or -mannan) on the cell wall of sensitive strains. The killing effect is presented by membrane permeation, cell lysis or inhibition of the cell cycle. It is also suggested that these killer glycoproteins, similar in structure to lectins, can mediate self-adhesion of the pathogenic microorganisms, thus stimulating their excretion from the intestines of infected mammals. It is supposed that the above interactions could be important for therapeutic applications, especially for enteric diseases. In order to fully understand the structural basis of the functions of killer glycoproteins, it is essential to characterize their glycosylation state and to determine the structure of all glycans attached to the proteins. In this paper, a strategic approach to the purification of yeast protein from complex biological mixtures is presented. The approach is structured into seven subassignments, each of which is essential for the successful isolation of a pure and biologically active yeast protein. The subassignments are: 1) decision on the use of the purified protein; 2) collecting information about the chemical, physical and biological properties of the protein; 3) establishing assays for the protein and its biological activity; 4) decision on the source of raw material; 5) development of an efficient extraction method; 6) development of a purification method; 7) establishment of optimum conditions for storage of the purified protein.

The influence of yeast killer toxins on the cytotoxicity of shiga-like toxins Part I ? The effect of killer toxins on mammalian cells

72%

Salek A. T.

2003

issue 1

244-256

It is evident that the results of preliminary experiments with 5 different yeast killer proteins did not show emphatic cytotoxicity or any adverse effect on any mammalian and embryo-cells. Moreover, they are likely to be harmless to animals? and humans? tissue cells. Therefore, they could be used to explain the pre-therapeutic effect on mammalian cells (mostly animals) in the case of infections by strains Escherichia coli, called EHEC. It was found that the yeast killer toxin from Williopsis mrakii can protect mammalian cells such as HeLa and Vero cells against the challenge by Shiga-Like-Toxins (derived from cultures of pathogenic strains of Escherichia coli). The final activities of tested mammalian cells are better when they are pre-treated by the killer protein, i.e. before the challenge with Shiga-Like-Toxins. It appears that this prophylactic effect could be very interesting for veterinary, which has been proved on a big population (about 2000) of healthy and ill (with diarrhoea, i.e. haemorrhagic colitis) pigs (manuscript ? confidential data). We can conclude that the yeast killer strains are probiotic, i.e. could reduce or eliminate fecal shedding of EHEC strains in pigs prior treated with the developed yeast toxins.

Refine search results

2 Biotechnologia

1 2003

1 2001

2 Salek A. T.

Search results

Yeast antimicrobial proteins

The influence of yeast killer toxins on the cytotoxicity of shiga-like toxins Part I ? The effect of killer toxins on mammalian cells