Production of listeriolysin by beta-hemolytic strains of XXXX .

@entity1 @entity3208 @entity22920 @entity95 @entity5125 @entity2975 @entity18778
Listeriolysin was isolated from target @entity95 erythrocyte membranes after lysis of the cells with partially purified toxin derived from a culture supernatant of @entity22920 . The membrane form of the toxin exhibited properties similar to those previously found for streptolysin O. Detergent-solubilized, delipidated listeriolysin was found to comprise a heterogeneous population of partially and fully circularized, amphiphilic oligomers whose embedment within the lipid bilayer generated large transmembrane pores. The molecular weight of the toxin monomer was estimated to be 55,000 to 60,000 by @entity3208 - @entity2975 gel electrophoresis. Immunological cross-reactions between the toxin and @entity18778 were demonstrable by @entity3208 - @entity2975 gel electrophoresis and immunoblotting. An immunoblot assay for detecting listeriolysin in agar-incorporated, lysed erythrocyte membranes was developed, and 28 defined, clinical isolates of @entity5125 were examined for toxin production. These isolates caused beta-hemolysis on the agar plates and had previously been regarded as listeriolysin producers. However, we found that only two isolates produced genuine listeriolysin, since the sensitive immunoblot assay entirely failed to detect the toxin in all other cases. We excluded that this finding derived from proteolytic degradation of membrane-bound toxin. Thus, the great majority of @entity1 pathogenic Listeria strains appear to produce one or several hemolysins that are immunologically and, by inference, molecularly distinct from the streptolysin O-related listeriolysin. We propose that the streptolysin O-related toxin be designated alpha-listeriolysin and that the other hemolysin(s) be termed beta-listeriolysin.
