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www.AutismRecoveryTreatment.com Autism Recovery – Clostridia bacteria can be quite problematic for many individuals with Autism. But there are various forms of bacteria and they each have their own markers for identification and their own ramifications. Biomedical autism intervention specialist physician, Dr. Kurt Woeller, explains. www.AutismRecoveryTreatment.com

This article is from Gut Pathogens , volume 5 . Abstract The gastrointestinal tract is a complex and dynamic network where an intricate and mutualistic symbiosis modulates the relationship between the host and the microbiota in order to establish and ensure gut homeostasis. Commensal Clostridia consist of gram-positive, rod-shaped bacteria in the phylum Firmicutes and make up a substantial part of the total bacteria in the gut microbiota. They start to colonize the intestine of breastfed infants during the first month of life and populate a specific region in the intestinal mucosa in close relationship with intestinal cells. This position allows them to participate as crucial factors in modulating physiologic, metabolic and immune processes in the gut during the entire lifespan, by interacting with the other resident microbe populations, but also by providing specific and essential functions. This review focus on what is currently known regarding the role of commensal Clostridia in the maintenance of overall gut function, as well as touch on their potential contribution in the unfavorable alteration of microbiota composition (dysbiosis) that has been implicated in several gastrointestinal disorders. Commensal Clostridia are strongly involved in the maintenance of overall gut function. This leads to important translational implications in regard to the prevention and treatment of dysbiosis, to drug efficacy and toxicity, and to the development of therapies that may modulate the composition of the microflora, capitalizing on the key role of commensal Clostridia, with the end goal of promoting gut health.

This article is from Environmental Microbiology , volume 14 . Abstract Three classes of low-G+C Gram-positive bacteria (Firmicutes), Bacilli, Clostridia and Negativicutes, include numerous members that are capable of producing heat-resistant endospores. Spore-forming firmicutes include many environmentally important organisms, such as insect pathogens and cellulose-degrading industrial strains, as well as human pathogens responsible for such diseases as anthrax, botulism, gas gangrene and tetanus. In the best-studied model organism Bacillus subtilis, sporulation involves over 500 genes, many of which are conserved among other bacilli and clostridia. This work aimed to define the genomic requirements for sporulation through an analysis of the presence of sporulation genes in various firmicutes, including those with smaller genomes than B. subtilis. Cultivable spore-formers were found to have genomes larger than 2300 kb and encompass over 2150 protein-coding genes of which 60 are orthologues of genes that are apparently essential for sporulation in B. subtilis. Clostridial spore-formers lack, among others, spoIIB, sda, spoVID and safA genes and have non-orthologous displacements of spoIIQ and spoIVFA, suggesting substantial differences between bacilli and clostridia in the engulfment and spore coat formation steps. Many B. subtilis sporulation genes, particularly those encoding small acid-soluble spore proteins and spore coat proteins, were found only in the family Bacillaceae, or even in a subset of Bacillus spp. Phylogenetic profiles of sporulation genes, compiled in this work, confirm the presence of a common sporulation gene core, but also illuminate the diversity of the sporulation processes within various lineages. These profiles should help further experimental studies of uncharacterized widespread sporulation genes, which would ultimately allow delineation of the minimal set(s) of sporulation-specific genes in Bacilli and Clostridia.

The second International Meeting on the Molecular Biology and Pathogenesis of the Clostridia was held at Seillac, France during the period 22-25 June 1997. The meeting was attended by leading researchers in the field from a variety of countries (list of attendees attached). The proceedings of the meeting were provided as a compilation of the abstracts of all oral and poster presentations at the meeting (attached). The meeting was considered a success and the third International Meeting will be held in Japan in Spring 2000.

The second International Meeting on the Molecular Biology and Pathogenesis of the Clostridia was held at Seillac, France during the period 22-25 June 1997. The meeting was attended by leading researchers in the field from a variety of countries (list of attendees attached). The proceedings of the meeting were provided as a compilation of the abstracts of all oral and poster presentations at the meeting (attached). The meeting was considered a success and the third International Meeting will be held in Japan in Spring 2000.

The second International Meeting on the Molecular Biology and Pathogenesis of the Clostridia was held at Seillac, France during the period 22-25 June 1997. The meeting was attended by leading researchers in the field from a variety of countries (list of attendees attached). The proceedings of the meeting were provided as a compilation of the abstracts of all oral and poster presentations at the meeting (attached). The meeting was considered a success and the third International Meeting will be held in Japan in Spring 2000.

The second International Meeting on the Molecular Biology and Pathogenesis of the Clostridia was held at Seillac, France during the period 22-25 June 1997. The meeting was attended by leading researchers in the field from a variety of countries (list of attendees attached). The proceedings of the meeting were provided as a compilation of the abstracts of all oral and poster presentations at the meeting (attached). The meeting was considered a success and the third International Meeting will be held in Japan in Spring 2000.

This article is from Biotechnology for Biofuels , volume 7 . Abstract Background: Clostridium autoethanogenum strain JA1-1 (DSM 10061) is an acetogen capable of fermenting CO, CO2 and H2 (e.g. from syngas or waste gases) into biofuel ethanol and commodity chemicals such as 2,3-butanediol. A draft genome sequence consisting of 100 contigs has been published. Results: A closed, high-quality genome sequence for C. autoethanogenum DSM10061 was generated using only the latest single-molecule DNA sequencing technology and without the need for manual finishing. It is assigned to the most complex genome classification based upon genome features such as repeats, prophage, nine copies of the rRNA gene operons. It has a low G + C content of 31.1%. Illumina, 454, Illumina/454 hybrid assemblies were generated and then compared to the draft and PacBio assemblies using summary statistics, CGAL, QUAST and REAPR bioinformatics tools and comparative genomic approaches. Assemblies based upon shorter read DNA technologies were confounded by the large number repeats and their size, which in the case of the rRNA gene operons were ~5 kb. CRISPR (Clustered Regularly Interspaced Short Paloindromic Repeats) systems among biotechnologically relevant Clostridia were classified and related to plasmid content and prophages. Potential associations between plasmid content and CRISPR systems may have implications for historical industrial scale Acetone-Butanol-Ethanol (ABE) fermentation failures and future large scale bacterial fermentations. While C. autoethanogenum contains an active CRISPR system, no such system is present in the closely related Clostridium ljungdahlii DSM 13528. A common prophage inserted into the Arg-tRNA shared between the strains suggests a common ancestor. However, C. ljungdahlii contains several additional putative prophages and it has more than double the amount of prophage DNA compared to C. autoethanogenum. Other differences include important metabolic genes for central metabolism (as an additional hydrogenase and the absence of a phophoenolpyruvate synthase) and substrate utilization pathway (mannose and aromatics utilization) that might explain phenotypic differences between C. autoethanogenum and C. ljungdahlii. Conclusions: Single molecule sequencing will be increasingly used to produce finished microbial genomes. The complete genome will facilitate comparative genomics and functional genomics and support future comparisons between Clostridia and studies that examine the evolution of plasmids, bacteriophage and CRISPR systems.

Recent increases in the understanding of clostridial genetics and pathogenesis prompted the planning of the First International Conference on the Molecular Genetics and Pathogenesis of the Clostridia. The specific aims of the Conference were to provide a centralized, broad-based forum on new developments, with particular emphasis on molecular biology, to encourage new insights, especially the identification of common themes in dostridial genetics and pathogenesis, to help train the next generation of dostridial researchers, to bring together basic and clinical scientists, stimulating the development of new ideas, perspectives, and collaborations, and to encourage reactivation of interest by the veterinary community in dostridial disease. Overall, the conference included 82 talks and posters, presented in eight oral and two poster sessions. Dr. Madelaine Sebald presented the keynote address The Development of Clostridial Genetics'. The oral sessions included 'Clostridia in Clinical Practice,' 'Genome Organization and Molecular Genetics,' 'Membrane-Active Toxins and Enzymes,' 'Neurotoxins,' Enterotoxins, 'Host-Pathogen Interactions,' "Regulation of virulence,' - and 'Prophylaxis, Therapy and Diagnosis.' There were also two afternoon poster sessions, which complemented the oral sessions. Overall, the conference was well received by both participants and organizers.

This article is from PLoS Pathogens , volume 10 . Abstract The bacteriophage ΦCD27 is capable of lysing Clostridium difficile, a pathogenic bacterium that is a major cause for nosocomial infection. A recombinant CD27L endolysin lyses C. difficile in vitro, and represents a promising alternative as a bactericide. To better understand the lysis mechanism, we have determined the crystal structure of an autoproteolytic fragment of the CD27L endolysin. The structure covers the C-terminal domain of the endolysin, and represents a novel fold that is identified in a number of lysins that target Clostridia bacteria. The structure indicates endolysin cleavage occurs at the stem of the linker connecting the catalytic domain with the C-terminal domain. We also solved the crystal structure of the C-terminal domain of a slow cleaving mutant of the CTP1L endolysin that targets C. tyrobutyricum. Two distinct dimerization modes are observed in the crystal structures for both endolysins, despite a sequence identity of only 22% between the domains. The dimers are validated to be present for the full length protein in solution by right angle light scattering, small angle X-ray scattering and cross-linking experiments using the cross-linking amino acid p-benzoyl-L-phenylalanine (pBpa). Mutagenesis on residues contributing to the dimer interfaces indicates that there is a link between the dimerization modes and the autocleavage mechanism. We show that for the CTP1L endolysin, there is a reduction in lysis efficiency that is proportional to the cleavage efficiency. We propose a model for endolysin triggering, where the extended dimer presents the inactive state, and a switch to the side-by-side dimer triggers the cleavage of the C-terminal domain. This leads to the release of the catalytic portion of the endolysin, enabling the efficient digestion of the bacterial cell wall.

The program and abstracts of the Third International Meeting on the Molecular Genetics and Pathogenesis of the Clostridia is presented.

The 4 International Meeting on the Molecular Genetics and pathogenesis of the Clostridia was held at the Woods Role Marine Biological Laboratory during the period 26th - 3Oth April 2003. The aim of this meeting was to bring together scientists from around the world who are working on the pathogenic clostridia to discuss recent results and to facilitate discussions and the exchange of new information and ideas 130 delegates from a range of countries attended the meeting.

(1) Metabolic differentiation to solventogenesis with slowing growth rate is sequential rather than simultaneous in Clostridium beijerinckii, with the production of butanol occurring in stage III of sporulation. (2) A pathway to n-propanol rather than to 2-propanol appears in this species at very slow growth under carbon limitation. (3) A constant fraction of carbon-energy substrate is used by Clostridium strain C7 for cellulase secretion at any growth rate: exoenzyme production is independent of maintenance energy costs and can therefore be produced efficiently at any growth rate. (4) Transformation in Bacillus subtilis occurs with maximum frequency at a doubling time of 2-3 hours, a region in which the cell is switching from anabolic to catabolic limitation.