Finished Whole-Genome Sequences of Clostridium butyricum Toxin Subtype E4 and Clostridium baratii Toxin Subtype F7 Strains.

Clostridium butyricum and Clostridium baratii species have been known to produce botulinum toxin types E and F, respectively, which can cause botulism, a rare but serious neuroparalytic disease. Here, we present finished genome sequences for two of these clinically relevant strains.

Finished Whole-Genome Sequences of Two Clostridium botulinum Type A(B) Isolates.

Clostridium botulinum secretes a potent neurotoxin that causes devastating effects when ingested, including paralysis and death if not treated. In the United States, some clinically significant strains produce toxin type A while also harboring a silent B gene. These are the first two closed genome sequences published for this subset.

Finished Whole-Genome Sequence of Clostridium argentinense Producing Botulinum Neurotoxin Type G.

Here, we present a closed genome sequence for Clostridium argentinense strain 89G, the first strain identified to produce botulinum neurotoxin type G (BoNT/G). Although discovered in 1970, to date, there have been no reference quality sequences publicly available for this species.

Characterizing the fecal microbiota of infants with botulism.

BACKGROUND: Infant botulism is the most prevalent form of botulism in the USA, representing 68.5 % of cases reported from 2001-2012. Infant botulism results when botulinum toxin-producing clostridia (BTPC) colonize the infant gut with concomitant in vivo production of the highly potent botulinum neurotoxin (BoNT). The gut microbiota of infants with botulism is largely uncharacterized; therefore, it remains unclear whether the microbiota profile of these patients are distinct in composition, abundance, or diversity. To address this uncertainty, we employed 16S rRNA gene profiling to characterize the fecal microbiota in 14 stool samples among laboratory-confirmed and non-confirmed infant botulism cases. RESULTS: Seven bacterial phyla were identified among all 14 infant stool samples examined. Compared to samples from non-confirmed cases, the fecal microbiota of infant botulism patients displayed significantly higher Proteobacteria abundance. Of the 20 bacterial families identified, Enterobacteriaceae was significantly more abundant in samples from infants with botulism. Firmicutes abundance and the abundance ratio of Firmicutes/Proteobacteria was significantly lower in samples from infants with botulism. Lactobacillus spp. abundance was notably reduced in 12 of the 14 samples. Clostridium botulinum and Clostridium baratii were identified in low relative abundances in confirmed and non-confirmed samples based on their 16S rRNA gene profiles, although their toxigenicity remained undetermined. No significant differences were observed in the number of operational taxonomic units (OTUs) observed or in fecal microbiota diversity between laboratory-confirmed and non-confirmed samples. Correlations between individual phylum abundances and infant age were variable, and no significant differences were shown in number of OTUs observed or in fecal microbiota diversity between samples delineated by overall mean age. CONCLUSIONS: Significant differences in Proteobacteria, Firmicutes, and Enterobacteriaceae abundances were identified in the fecal microbiota of infants with botulism when compared to samples from non-confirmed cases. Fecal microbiota diversity was not significantly altered in infants with botulism, and a limited presence of BTPC was shown. It could not be determined whether the fecal microbiota profiles shown here were comparable prior to patient illness, or whether they were the direct result of infant botulism. The results of this study do, however, provide a detailed and descriptive observation into the infant gut microbiota after intestinal colonization by BTPC.