A genomic update on clostridial phylogeny: Gram-negative spore formers and other misplaced clostridia

A genomic update on clostridial phylogeny: Gram-negative spore formers and other misplaced clostridia.

The class Clostridia in the phylum Firmicutes (formerly low-G+C Gram-positive bacteria) includes diverse bacteria of medical, environmental and biotechnological importance. The Selenomonas-Megasphaera-Sporomusa branch, which unifies members of the Firmicutes with Gram-negative-type cell envelopes, was recently moved from Clostridia to a separate class Negativicutes. However, draft genome sequen...

Medical Applications of Clostridia and Clostridial Toxins

The bacterial genus Clostridium produces a diverse array of protein toxins, many of which have played an important role in disease and medicine. Although initially known for their ability to do harm, many clostridial toxins have been shown to have therapeutic value for a diverse array of diseases. The articles included in this special issue provide insight into some of that diversity and show t...

Editorial: Spores and Spore Formers

Carotenoids present in halotolerant Bacillus spore formers.

Six isolates of pigmented spore-forming bacteria were recovered from human faeces from subjects in Vietnam. 16S rRNA analysis demonstrated close association with known pigmented Bacillus species. All isolates were able to tolerate growth on 8% NaCl and were resistant to arsenate, characteristics that make them most related to Bacillus indicus. Two visible pigments were apparent, a yellow pigmen...

Genomic determinants of sporulation in Bacilli and Clostridia: towards the minimal set of sporulation-specific genes

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, b...