Differentiation of the Gene Clusters Encoding Botulinum Neurotoxin Type A Complexes in Clostridium botulinum Type A, Ab, and A(B) Strains

Abstract

We describe a strategy to identify the clusters of genes encoding components of the botulinum toxin type A (boNT/A) complexes in 57 strains of Clostridium botulinum types A, Ab, and A(B) isolated in Italy and in the United States from different sources. Specifically, we combined the results of PCR for detecting the ha33 and/or p47 genes with those of boNT/A PCR-restriction fragment length polymorphism analysis. Three different type A toxin gene clusters were revealed; type A1 was predominant among the strains from the United States, whereas type A2 predominated among the Italian strains, suggesting a geographic distinction between strains. By contrast, no relationship between the toxin gene clusters and the clinical or food source of strains was evident. In two C. botulinum type A isolates from the United States, we recognized a third type A toxin gene cluster (designated type A3) which was similar to that previously described only for C. botulinum type A(B) and Ab strains. Total genomic DNA from the strains was subjected to pulsed-filed gel electrophoresis and randomly amplified polymorphic DNA analyses, and the results were consistent with the boNT/A gene clusters obtained.

Toxin Detection in Patients' Sera by Mass Spectrometry during Two Outbreaks of Type A Botulism in France

“…It is assumed that food contamination reflects the prevalence of C. botulinum types in the environment where the food is prepared (6). This is consistent with the fact that C. botulinum A2 is frequent in southern Italy (8) and that the contaminated food from Corsica, which is close to Italy, also contains a subtype A2 strain.…”

Comparison of DNA Fingerprinting Methods for Use in Investigation of Type E Botulism Outbreaks in the Canadian Arctic

“…PFGE is the current gold standard method used to differentiate strains of bacterial pathogens of public health significance, to assess the epidemic spread of infectious diseases in hospitals (32,48), and to trace food-borne outbreaks (1, 8, 36). Although PFGE is reproducible and discriminatory, some strains of C. botulinum types A and E have not been typeable using PFGE (20)(21)(22) due to DNA degradation, despite the use of formaldehyde prior to DNA isolation. In this study, however, we have shown that the addition of 50 M thiourea to the running buffer overcomes the problems of DNA degradation, with all 21 type E isolates that were previously untypeable now producing high-quality fingerprints.…”

“…PFGE and RAPD typing have revealed extensive genetic biodiversity among type E isolates (22,29). PFGE has recently been applied for typing outbreak strains of C. botulinum group I (20), but its usefulness during a food-borne outbreak investigation remains unknown, in part because of the low incidence of botulism outbreaks yielding isolates from clinical, food, and environmental sources (33).…”

Šlapinimosi sutrikimai po stuburo traumų ir jų gydymas botulino toksino A endovezikinėmis injekcijomis

“…Yra skiriami septyni skirtingi botulino neurotoksino tipai (A, B, C, D, E, F, G). Medicinoje dažniausiai yra naudojamas botulino neurotoksinas A [32].…”