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Eric A. Johnson - One of the best experts on this subject based on the ideXlab platform.

  • Clostridium | Clostridium botulinum
    Encyclopedia of Food Microbiology, 2014
    Co-Authors: Eric A. Johnson
    Abstract:

    Botulism is a neuroparalytic disease in humans and animals resulting from the actions of neurotoxins produced by Clostridium botulinum and rare strains of Clostridium butyricum and Clostridium baratii . botulinum-producing organisms are dispersed widely throughout the world in soils and sediments and the intestine of animals. botulinum neurotoxins (BoNTs) are the most poisonous toxins known by the oral and intravenous routes. Foodborne botulism occurs following ingestion of BoNT preformed in foods, while infant botulism results from colonization of the intestine with toxin production and absorption into the circulation. Botulism is a serious concern of the food industry and regulatory agencies because of the resistance properties of spores of C . botulinum , and the organism's ability to grow and form toxin in many foods. The detection of BoNT in the affected human or in consumed foods provides a diagnosis of botulism.

  • Topley and Wilson's Microbiology and Microbial Infections - Clostridium botulinum and Clostridium tetani
    Topley & Wilson's Microbiology and Microbial Infections, 2010
    Co-Authors: Eric A. Johnson
    Abstract:

    1 Genus and Species Definitions 2 Historical Background of the Pathogenic Clostridia 3 Milestones in the Understanding of Botulism and Tetanus 4 Classification of Neurotoxigenic Clostridia 5 Habitats of Pathogenic Clostridia 6 Physical and Metabolic Properties of Pathogenic Clostridia including C. botulinum and C. tetani 7 Growth Properties of C. botulinum and C. tetani 8 Physiology of C. botulinum and C. tetani 9 Descriptions of the Species C. botulinum, C. tetani, and other Neurotoxigenic Clostridia 10 botulinum Neurotoxins 11 Detection of botulinum and Tetanus Neurotoxins 12 Genomics of Clostridium tetani and Clostridium botulinum 13 Susceptibility of Neurotoxigenic Clostridia to Chemical and Physical Agents 14 Epidemiology and Clinical Aspects 15 Use of botulinum Toxin in Medicine 16 Safety Precautions for Working with C. botulinum, C. tetani, and their Neurotoxins 17 Acknowledgments Keywords: Clostridium botulinum and Clostridium tetani; understanding botulism and tetanus; pathogenic clostridia habitats; C. botulinum and C. tetani growth properties; botulinum neurotoxins; Clostridium tetani and Clostridium botulinum genomics; susceptibility of neurotoxigenic clostridia to chemical and physical agents; botulinum toxin use in medicine

  • Plasmid encoded neurotoxin genes in Clostridium botulinum serotype A subtypes.
    Biochemical and biophysical research communications, 2007
    Co-Authors: Kristin M Marshall, Marite Bradshaw, Sabine Pellett, Eric A. Johnson
    Abstract:

    Clostridium botulinum, an important pathogen of humans and animals, produces botulinum neurotoxin (BoNT), the most poisonous toxin known. We have determined by pulsed-field gel electrophoresis (PFGE) and Southern hybridizations that the genes encoding BoNTs in strains Loch Maree (subtype A3) and 657Ba (type B and subtype A4) are located on large (approximately 280 kb) plasmids. This is the first demonstration of plasmid-borne neurotoxin genes in Clostridium botulinum serotypes A and B. The finding of BoNT type A and B genes on extrachromosomal elements has important implications for the evolution of neurotoxigenicity in clostridia including the origin, expression, and lateral transfer of botulinum neurotoxin genes.

  • Transposon Tn916 mutagenesis in Clostridium botulinum.
    Applied and environmental microbiology, 1991
    Co-Authors: Wei-jen Lin, Eric A. Johnson
    Abstract:

    The study of toxinogenesis and other properties in Clostridium botulinum is limited by the absence of genetic methods that enable construction of defined mutants. In this study, tetracycline-resistant transposon Tn916 in Enterococcus faecalis was conjugatively transferred in filter matings to group I Clostridium botulinum strains Hall A and 113B. The Tn916 transfer frequencies to C. botulinum ranged from 10(-8) to 10(-5) Tcr transconjugant per recipient depending on the donor strain. Southern blot analyses of EcoRI or HindIII chromosomal digests extracted from randomly selected Tcr transconjugants showed that the transposon inserted at different sites in the recipient chromosome, and the copy number of Tn916 varied from one to three. Tn916 insertion gave several different auxotrophic mutants. This approach should be useful for the study of genes important in growth, survival, and toxinogenesis in C. botulinum.

Fu Si-w - One of the best experts on this subject based on the ideXlab platform.

  • The isolation and identification of a type C strain of Clostridium botulinum
    Modern Preventive Medicine, 2013
    Co-Authors: Fu Si-w
    Abstract:

    OBJECTIVE The study is examined for distribution of Clostridium botulinum in Northwest, China. METHODS All soils from Gansu Province were washed by 0.2% gelatin phosphate buffer, and then carried out with the methods of bacteria-proliferating, isolating culture repeatedly. The isolated strain was identified by toxin determination and biochemical characteristics. RESULTS 2 of the 175 soil specimens appeared typical symptoms of botulism, and only 1 could be completely neutralized by type C botulinum antitoxin. CONCLUSION The strain is identified as type C Clostridium botulinum.

Peipei Liu - One of the best experts on this subject based on the ideXlab platform.

  • The Fur Transcription Regulator and Fur-Regulated Genes in Clostridium botulinum A ATCC 3502
    Journal of biomedicine & biotechnology, 2011
    Co-Authors: Weibin Zhang, Chengyuan Zang, Yingying Song, Peipei Liu
    Abstract:

    Clostridium botulinum is a spore-forming bacterium that can produce a very powerful neurotoxin that causes botulism. In this study, we have investigated the Fur transcription regulators in Clostridium botulinum and Fur-regulated genes in Clostridium botulinum A ATCC 3502. We found that gene loss may be the main cause leading to the different numbers of Fur transcription regulators in different Clostridium botulinum strains. Meanwhile, 46 operons were found to be regulated by the Fur transcription regulator in Clostridium botulinum A ATCC 3502, involved in several functional classifications, including iron acquisition, iron utilization, iron transport, and transcription regulator. Under an iron-restricted medium, we experimentally found that a Fur transcription regulator (CBO1372) and two operons (DedA, CBO2610–CBO2614 and ABC transporter, CBO0845–CBO0847) are shown to be differentially expressed in Clostridium botulinum A ATCC 3502. This study has provided-us novel insights into the diversity of Fur transcription regulators in different Clostridium botulinum strains and diversity of Fur-targeted genes, as well as a better understanding of the dynamic changes in iron restriction occurring in response to this stress.

Richard L. Whitman - One of the best experts on this subject based on the ideXlab platform.

Bal Ram Singh - One of the best experts on this subject based on the ideXlab platform.

  • Molecular characterization of type E Clostridium botulinum and comparison to other types of Clostridium botulinum.
    Biochimica et biophysica acta, 1998
    Co-Authors: X. Qian, Hemanta K. Sarkar, Bal Ram Singh
    Abstract:

    Determination of nucleotide sequence upstream to the neurotoxin binding protein (NBP) gene of type E Clostridium botulinum has revealed an open reading frame whose stop codon is only 18 bp apart from the start codon of the NBP gene. Amino acid sequence derived from the corresponding nucleotide sequence suggested the existence of the open reading frame as a 47.8 kDa protein (P-48). Protein data bank search revealed that the 47.8 kDa protein has 80% sequence identity to P-47 of type F C. botulinum. The gene organization of type E. Clostridium botulinum was predicted and compared to other types of C. botulinum. In type E C. botulinum, genes for the P-48, the neurotoxin binding protein and the neurotoxin form an operon which was similar to that of type F C. botulinum. However, type E C. botulinum has a P-18 gene instead of P-21 gene observed in type F C. botulinum, both located upstream to their respective P-48/P-47 gene.