EVALUATED THE PROTEOLYTIC ACTIVITY OF THE DIFFERENT BOTULINUM NEUROTOXIN TIPO A AGAINST TARGET PROTEINS OBTAINED OF STRAIN OF MENDOZA, ARGENTINA

CABALLERO, P.; TRONCOSO, M.; FERNANDEZ, R.; SOSA, MA.

San Luis

Congreso; XXXII Jornadas de la Sociedad de Biología de Cuyo; 2014

Sociedad de Biología de Cuyo

NTBo type A, produced by C.botulinum (Cb), is prevalent serotype in soil strain of Mendoza. The main reservoir for Cb soil (Su) and possibly one of infection sources for developing infant botulism (IB). The high incidence of IB in breast milk fed infants with history of no any other complementary feeding suggest that soil is an important source of infection. In previous studies we found that culture of strains obtained from Su and from IB differ in morphology and also in some biological properties of NTBo. In this study we evaluated the proteolytic activity (PA) of the different NTBo against target proteins. Rat brain homogenates were incubated with NTBo from either Su or IB and compared with that of A-Hall strain, under controlled conditions. Proteolysis of SNAP-25 and synaptobrevin was analysed by Western blot, using the corresponding monoclonal antibodies and detected by chemiluminescence method. The specific bands of each protein were normalized to actin detection. We observed that both proteins are cleaved to smaller fragments by the Su toxin, and at lesser extent the A-Hall. However, the IB toxin showed scarce activity against these synaptic proteins. The differential effect of the toxins is somehow in accordance with the higher toxicity of Su in comparison with the other strains. The differences between Su and IB toxins indicate a more powerful proteolytic toxic activity from Su that IB. Also could indicate that the bacterial is highly modified during staying in the digestive tract of the infants.