Guido Grandi

Cloning of a novel pilin‐like gene from Bordetella pertussis: homology to the fim2 gene

A search for pilin genes in a Bordetella pertussis (Bp) genomic library has led to the identification of several clones which hybridize to synthetic oligonucleotides with sequences derived from amino acid sequences of Bp fimbrial subunits. One of these clones (corresponding to a gene we have named fimX) contains an open reading frame encoding a protein with a molecular weight of about 20 kD and a sequence similar but not identical to the fimbrial subunit fim2 and to other fimbrial protein sequences. In this communication we present the cloning and nucleotide sequence of the fimX gene and its homology to the fim2 gene. A genomic analysis on the positional relationship between the two genes is also presented.

New plasmid expression vectors for Bacillus subtilis

The construction of new cloning vectors for Bacillus subtilis is described. They are derived from the in vitro joining of parts of pE194 and pUB110 DNAs. Their common feature is to present a cloning site immediately after the promoter and ribosome binding site of the erythromycin resistance gene, allowing the insertion and expression of either sticky or blunt ended DNA fragments coding for any heterologous gene. The cloning and expression of Escherichia coli beta-lactamase and EcoRI methylase are given as examples. The enzymes are efficiently synthesized by B. subtilis cells.

Genomics and Proteomics in Vaccine Design

In 1881, Louis Pasteur, the father of bacterial vaccines and immunology, demonstrated publicly the first vaccine against a bacterial infection. His vaccine, against anthrax in sheep, consisted of Bacillus anthracis attenuated by high-temperature growth in his laboratory. At Pouilly-Le-Fort, a small village close to Paris, he vaccinated 25 sheep then challenged these plus 25 controls with a virulent strain of B. anthracis. All 25 control sheep died, and all 25 immunized sheep survived. This remarkably successful experiment silenced even his most vocal detractors and paved the way for the development of antibacterial vaccines for use in man. Remarkably, the anthrax vaccine produced today and used to immunize American soldiers is produced in a similar fashion except that a stable partially attenuated strain is used. The second bacterial vaccine was produced by Ramon in 1924 and was essentially a formaldehyde-inactivated supernatant from cultures of Corynebacterium diphtheriae. Again, current vaccines against diphtheria are produced in the same way except that the inactivated toxin that confers protection is partially purified from the culture supernatant. The story continues with the inactivated whole-cell vaccine against Bordetella pertussis (whooping cough) first produced in the late 1940s and still used today in developing countries. It is unlikely that these vaccines would gain FDA approval today. They are still accepted because several decades of use has demonstrated that they are reasonably safe and very effective. It should not be forgotten that these vaccines, together with the smallpox and polio vaccines, essentially eliminated the major causes of childhood mortality in the industrialized world.