abstract book - Clostridia

GENE TOOLS AND THEIR APPLICATION TO CLOSTRIDIUM
BOTULINUM
N.P. Minton, C.M. Cooksley, I. Davis, J.T. Heap, S.T. Cartman, B.A.
Blount & O.J. Pennington.
Institute of Infection, Immunity & Inflammation, Centre for Biomolecular
Sciences, School of Molecular Medical Sciences, University of
Nottingham, Nottingham, GN7 2RD, UK.
Despite the medical and industrial importance of the genus Clostridium
our understanding of their basic biology lags behind that of their more
illustrious counterpart, Bacillus. The advent of the genomics era has
provided new insights, but full exploitation of the data becoming available
is being hindered by a lack of mutational tools for functional genomic
studies. Thus, in the preceding decades the number of clostridial mutants
generated has been disappointingly low. On the one hand, the absence
of effective transposon elements has stymied random mutant generation.
On the other hand, the construction of directed mutants using classical
methods of recombination-based, allelic exchange has met with only
limited success. Indeed, in the majority of clostridial species mutants are
largely based on integration of plasmids by a Campbell-like mechanism.
Such single crossover mutants are unstable. As an alternative,
recombination-independent strategies have been developed that are
reliant on retargeted group II intron. One element in particular, the
ClosTron, has been devised which provides the facility for the positive
selection of mutants. ClosTron-mediate mutant generation is extremely
rapid, highly efficient and reproducible. Moreover the mutants made are
extremely stable. Its deployment considerably expands current options
for functional genomic studies in Clostridium botulinum.
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