New model of membrane damage by staphylococcal alpha toxin.

Evaluation of lysis of rabbit erythrocytes by staphylococcal alpha toxin was done through the turbidometric assay. The results showed that the absorbance curves produced by turbidometric assay, displayed several changes in the slope which indicated the presence of several mechanisms of action of alpha toxin on erythrocytes. The first derivative analysis of the lysis curve, revealed that there were two specific peaks present. However, turbidometric assay produced high variation in these peaks from one experiment to the other. The variation was related to the changes occurring in the erythrocytes. Erythrocytic Band 3 is a proven receptor for alpha toxin, and it was found that as erythrocytes aged, there was a gradual degradation of Band 3. Young erythrocytes according to the model, are capable of inducing the damage by a hexameric form due to the presence of the intact Band 3 which permits the assembly of monomers into haxamers. These cells can also be lysed by a less effective monomeric form of alpha toxin. The old erythrocytes on the other hand are capable of inducing lysis of a monomeric form only, since Band 3 is broken down in these cells and cannot induce the aggregation of monomers into hexameric units. (Abstract shortened by UMI.)Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1992 .K368. Source: Masters Abstracts International, Volume: 31-03, page: 1135. Chair: H. B. Fackrell. Thesis (M.Sc.)--University of Windsor (Canada), 1991