John T. Heap

TL;DR: It is shown that isogenic mutants of C. difficile producing either toxin A or toxin B alone can cause fulminant disease in the hamster model of infection, re-establish the importance of both toxin A and toxin B and highlight the need to continue to consider both toxins in the development of diagnostic tests and effective countermeasures against C. diffuse.

TL;DR: A mutagenesis system based on the mobile group II intron from the ltrB gene of Lactococcus lactis to function in clostridial hosts is adapted, which is highly efficient and reproducible, and should revolutionize functional genomic studies inClostridia.

TL;DR: The specification, design and construction of a standardized modular system for Clostridium-Escherichia coli shuttle plasmids was described, and existing replicons and selectable markers were incorporated, along with a novel clostridial replicon.

TL;DR: The improved ClosTron system supersedes the prototype plasmid pMTL007 and the original method, and exploits the potential of Group II introns more fully, and means mutants can now be constructed with very little time and effort for the researcher.

TL;DR: An aberrant tcdC genotype does not provide a broadly applicable rationale for the perceived notion that PCR ribotype 027 strains are “high-level” toxin producers, and may well explain why several studies have reported that an aberranttcdC gene does not predict increased toxin production or, indeed, increased virulence.