Dual-Toxin ("Bivalent") Infant Botulism in California, 1976-2020: Epidemiologic, Clinical, and Laboratory Aspects.

Objective: To assess the consequences of infant botulism that result from Clostridium botulinum strains that produce 2 botulinum toxin serotypes, termed "bivalent."

Study Design: Epidemiologic investigations used a standard questionnaire. Clostridium botulinum strains were isolated by standard methods.

Closed Genome Sequence of Clostridium botulinum Strain IBCA10-7060 Type Bh.

Clostridium botulinum strain IBCA10-7060 was isolated from a stool specimen from an infant botulism patient and is the only Clostridium botulinum strain known that produces botulinum toxin type H. We present here its 4.09-Mbp closed genome sequence.

Molecular epidemiology of infant botulism in California and elsewhere, 1976-2010.

Background: Infant botulism (IB), first identified in California in 1976, results from Clostridium botulinum spores that germinate, multiply, and produce botulinum neurotoxin (BoNT) in the immature intestine. From 1976 to 2010 we created an archive of 1090 BoNT-producing isolates consisting of 1012 IB patient (10 outpatient, 985 hospitalized, 17 sudden death), 25 food, 18 dust/soils, and 35 other strains.

Methods: The mouse neutralization assay determined isolate toxin type (56% BoNT/A, 32% BoNT/B).

Arrangement of the Clostridium baratii F7 toxin gene cluster with identification of a σ factor that recognizes the botulinum toxin gene cluster promoters.

Botulinum neurotoxin (BoNT) is the most poisonous substances known and its eight toxin types (A to H) are distinguished by the inability of polyclonal antibodies that neutralize one toxin type to neutralize any of the other seven toxin types. Infant botulism, an intestinal toxemia orphan disease, is the most common form of human botulism in the United States. It results from swallowed spores of Clostridium botulinum (or rarely, neurotoxigenic Clostridium butyricum or Clostridium baratii) that germinate and temporarily colonize the lumen of the large intestine, where, as vegetative cells, they produce botulinum toxin.

Molecular characterization of a novel botulinum neurotoxin type H gene.

We sequenced the 2 botulinum toxin gene clusters of Clostridium botulinum strain IBCA10-7060 type Bh. The sequence of bont/H differed substantially from the sequences of the 7 known bont genes for toxin types A-G. The 5' one-third terminus of bont/H that codes for the botulinum toxin light chain differed markedly from the light chain coding sequences of toxin types A-G.

Clostridium botulinum strain Af84 contains three neurotoxin gene clusters: bont/A2, bont/F4 and bont/F5.

Sanger and shotgun sequencing of Clostridium botulinum strain Af84 type Af and its botulinum neurotoxin gene (bont) clusters identified the presence of three bont gene clusters rather than the expected two. The three toxin gene clusters consisted of bont subtypes A2, F4 and F5. The bont/A2 and bont/F4 gene clusters were located within the chromosome (the latter in a novel location), while the bont/F5 toxin gene cluster was located within a large 246 kb plasmid.

Expression of recombinant green fluorescent protein in Bacillus methanolicus.

Microbial biocatalysts are used in a wide range of industries to produce large scale quantities of proteins, amino acids, and commodity chemicals. While the majority of these processes use glucose or other low-cost sugars as the substrate, Bacillus methanolicus is one example of a biocatalyst that has shown sustained growth on methanol as a carbon source at elevated temperature (50-53°C optimum) resulting in reduced feed and utility costs. Specifically, the complete chemical process enabled by this approach takes methane from natural gas, and following a low-cost conversion to methanol, can be used for the production of high value products.

Interfering with different steps of protein synthesis explored by transcriptional profiling of Escherichia coli K-12.

Escherichia coli responses to four inhibitors that interfere with translation were monitored at the transcriptional level. A DNA microarray method provided a comprehensive view of changes in mRNA levels after exposure to these agents. Real-time reverse transcriptase PCRanalysis served to verify observations made with microarrays, and a chromosomal grpE::lux operon fusion was employed to specifically monitor the heat shock response.