[Molecular characterisation of the haemolytic isolates of Bacillus anthracis originated in Poland].
Bacillus anthracis is generally considered non-haemolytic, when cultured on the solid media. However, strains capable to lyse sheep erythrocytes have been reported. Anthrolysin O, an orthologue of cereolysin was proposed as a putative haemolysin of B. anthracis.


OBJECTIVE
to determine whether anthrolysin O, haemolytic enterotoxin HBL and the pleiotropic regulator PlcR that activates antrholysin O production are associated with a haemolytic activity of B. anthracis strains isolated in Poland.


METHODS
in total 8 B. anthracis strains - the fully virulent BL1 and seven the pXO2 lacking strains including: a vaccine strain Sterne 34F2 together with three haemolytic and three non-haemolytic strains isolated from different samples of the same animal died from anthrax in Poland.


METHODS
The haemolytic activity was detected using Columbia agar plates supplemented with 5% of sheep blood. Anthrolvsin O, cereolysin and gene hblA encoding the key subunit of the HBL were detected by PCR. In addition, the plcR gene fragment containing the B. anthracis specific non-sense mutation was analysed by the DNA sequencing. Ten marker loci based MLVA genotyping was performed to distinguish tested strains.


RESULTS
The alo gene encoding anthrolysin O was detected in both the haemolytic and non-haemolytic strains while hblA was absent. The B. anthracis specific plcR non-sense mutation was detected in both the groups of tested strains, suggesting that the haemolysis in tested strains may rather be conferred by the PlcR-independent factors. Moreover, haemolytic and non-haemolytic strains were indistinguishable by the MLVA. Obtained results may argue the haemolytic and non-haemolytic strains are isogenic and most probably a single mutational event is responsible for the haemolytic phenotype induction.
Gierczyński
Rafał
R
Zakład Bakteriologii PZH w Warszawie.
Zasada
Aleksandra A
AA
Kałuzewski
Stanisław
S
Jagielski
Marek
M
D000942:Antigens, Bacterial / Q000235:genetics; D001408:Bacillus anthracis / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism; D006461:Hemolysis / Q000235:genetics*; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D018598:Minisatellite Repeats / Q000235:genetics; D008969:Molecular Sequence Data; D011044:Poland; D016133:Polymerase Chain Reaction; D013045:Species Specificity; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D006460:Hemolysin Proteins; D008562:Membrane Glycoproteins; C099480:PlcR protein, Bacillus; D015534:Trans-Activators; D037521:Virulence Factors; C498000:anthrolysin O, Bacillus anthracis; C083961:hemolysin BL protein, Bacillus; C006953:cereolysin