Neurotoxins from Clostridium botulinum (serotype A) isolated from the soil of Mendoza (Argentina) differ from the A-Hall archetype and from that causing infant botulism

PATRICIA CABALLERO; TRONCOSO M; PATTERSON SI; LÓPEZ GOMEZ C; RA FERNANDEZ; SOSA MA

TOXICON

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2016 vol. 121 p. 30 - 35

0041-0101

Mendoza. The soil is the main reservoir for C.botulinum and is possibly one of the infection sources ininfant botulism. In this study, we characterized and compared autochthonous C. botulinum strains andtheir neurotoxins. Bacterial samples were obtained from the soil and from fecal samples collected fromchildren with infant botulism. We first observed differences in the appearance of the colonies betweenstrains from each source and with the A Hall control strain. In addition, purified neurotoxins of bothstrains were found to be enriched in a band of 300 kDa, whereas the A-Hall strain was mainly made up ofa band of ~600 kDa. This finding is in line with the lack of hemagglutinating activity of the neurotoxinsunder study. Moreover, the proteolytic activity of C. botulinum neurotoxins was evaluated against SNARE(soluble N-ethylmaleimide-sensitive factor-attachment protein receptor) proteins from rat brain. It wasobserved that both, SNAP 25 (synaptosomal-associated protein 25) and VAMP 2 (vesicle-associatedmembrane protein) were cleaved by the neurotoxins isolated from the soil strains, whereas the neurotoxinsfrom infant botulism strains only induced a partial cleavage of VAMP 2. On the other hand, theneurotoxin from the A-Hall strain was able to cleave both proteins, though at a lesser extent. Our dataindicate that the C.botulinum strain isolated from the soil, and its BoNT, exhibit different propertiescompared to the strain obtained from infant botulism patients, and from the A-Hall archetype.