Insertional mutations in mycobacteria

Chemistry: molecular biology and microbiology – Micro-organism – per se ; compositions thereof; proces of... – Bacteria or actinomycetales; media therefor

Reexamination Certificate

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C424S093100, C424S093200, C435S243000, C435S252100, C435S254110, C435S863000, C435S864000, C435S865000, C435S866000

Reexamination Certificate

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06566121

ABSTRACT:

This invention relates to mutagenesis of mycobacteria. More particularly, this invention relates to the generation of insertional mutations in mycobacteria.
Certain mycobacteria represent major pathogens of man and animals. For example, tuberculosis is generally caused in humans by
Mycobacterium tuberculosis,
and in cattle by
Mycobacterium bovis,
which may also be transmitted to humans and other animals.
Mycobacteria leprae
is the causative agent of leprosy.
M. tuberculosis
and mycobacteria of the avium-intracellulare-scrofulaceum group (MAIS group) represent major opportunistic pathogens of patients with acquired immune deficiency syndrome (AIDS).
M. pseudotuberculosis
is a major pathogen of cattle.
On the other hand, Bacille Calmette-Guerin, or BCG, an avirulent strain of
M. bovis,
is widely used in human vaccines, and in particular is used as a live vaccine, which is protective against tuberculosis. BCG is the only childhood vaccine which is currently given at birth, has a very low incidence of adverse effects, and can be used repeatedly in an individual (e.g., in multiple forms). In addition, BCG and other mycobacteria (e.g.,
M. smegmatis
), employed in vaccines, have adjuvant properties among the best currently known and, therefore, stimulate a recipient's immune system to respond to antigens with great effectiveness.
It has been suggested by Jacobs, et al,
Nature,
Vol. 327, No. 6122, pgs. 532-535 (Jun. 11, 1987) that BCG could be used as a host for the construction of recombinant vaccines. In other words, it was suggested to take an existing vaccine (in this case against tuberculosis) and expand its protective repertoire through the introduction of one or more genes from other pathogens. Because BCG vaccines are administered as live bacteria, it is essential that any foreign antigens, polypeptides, or proteins expressed by the bacteria are not lost from the bacteria subsequent to vaccination.
Transformation, the process whereby naked DNA is introduced into bacterial cells, has been carried out successfully in mycobacteria. Jacobs, et al (1987), hereinabove cited, have described transformation of mycobacteria through chemical methods, and Snapper, et al; PNAS, Vol. 85, pgs. 6987-6991 (September 1988) have described transformation of mycobacteria by electroporation. Electroporation can give from 10
5
to 10
6
transformants per &mgr;g of plasmid DNA and such plasmid DNA's may carry genes for resistance to antibiotic markers such as kanamycin (Snapper, et al 1988) to allow for selection of transformed cells from non-transformed cells.
Jacobs, et al (1987) and Snapper, et al (1988) have also described the use of cloning vehicles, such as plasmids and bacteriophages, for carrying genes of interest into mycobacteria.
Combination of the above-mentioned techniques, along with standard tools of molecular cloning (e.g., use of restriction enzymes, etc.) allows the cloning of genes of interest into vectors and introduction of such genes into mycobacteria. To express these genes, it is important to have available signals for gene expression, in particular, transcription promoter elements. Such promoter elements have been isolated from mycobacterial heat shock genes, and have been used to express foreign antigens in mycobacteria.
Molecular genetics of mycobacteria, however has only recently begun to be developed, in part because mycobacteria present formidable obstacles to genetic study in that mycobacteria, in general, clump in culture and grow very slowly. The direct selection of mutants by employing transposons (also known as random insertional mutagenesis) has been a useful approach to the mutational analysis of microbial pathogenesis (Isberg, et al.,
Curr. Top. Microbiol. Inmunol.
, Vol. 118, pgs. 1-11 (1985); Taylor, et al.,
J. Bacteriol,
Vol. 171, pgs. 1870-1878 (1989); Fields, et al.,
Science,
Vol. 243, pgs. 1059-1061 (1989); Bernardini, et al.,
Proc. Nat. Acad. Sci.,
Vol. 86, pgs. 3867-3871 (1989)); such selection of mutants, however, had not been described in mycobacteria.
Objects of the present invention include the generation of mutations in mycobacteria and/or the introduction of heterologous genes into mycobacteria; in particular, the generation of mutations of mycobacteria employed in vaccines, such as BCG, as well as the generation of mutations in pathogenic mycobacteria, such as
M. tuberculosis
or
M. leprae,
whereby such mutations make the mycobacteria non-pathogenic. Heterologous genes which may be introduced into the mycobacteria include, but are not limited to, genes for protective antigen(s) for a variety of pathogens, and/or for other therapeutic agents.


REFERENCES:
patent: 5504005 (1996-04-01), Bloom et al.
patent: 5672345 (1997-09-01), Curtiss, III
patent: 0166410 (1986-01-01), None
patent: 8806626 (1988-09-01), None
patent: WO8806626 (1988-09-01), None
patent: 90/10101 (1990-09-01), None
patent: 9010701 (1990-09-01), None
patent: 9000594 (1990-12-01), None
patent: 9015873 (1990-12-01), None
patent: WO9201783 (1992-02-01), None
patent: WO9201796 (1992-02-01), None
patent: WO9221374 (1992-12-01), None
patent: WO9222326 (1992-12-01), None
Lugosi—Tubercle 70:159-170, 1989 Genetic Transformation of BCG.*
Woodley et al, Antimicrobical Agents & ChemoTheropy 19:571-574, 1981.*
Cirillo et al Abstracts of the Annual Meeting of the American Society for Microbiology May 13-17, 1990 p. 143, Abstract #U13.*
Hayes et al The Genetics of Bacteria & Thier Viruses, p. 120-124, 1968.*
Neidhardt, Escherichia Coli and Salmonella Typhiumvrium Cellular & Molecular Biology vol. 1 p. X & X1.*
Martin et al Nature 345:739-743, 1990.*
Snapper et al Mol. Microbiology 4:1911-1919, 1990.*
Snapper et al Dissertation International 52/05-B p. 2415, Abstract Only, 1990.*
Ranes et al. Journal of Bacteriology 172:2793-2797 (May 1990).*
Woodley et al Antimicrob., Agents and ChemoTherapy 19:571-574, 1981.*
Subramanyam et al Journal of General Microbiology 135:2651-2654, 1989.*
Subramanyam et al Letters in Applied Microbiology 8:161-164, 1989.*
Cirillo, et al., A Novel Transposon Trap for Mycobacteria: Isolation and Characterization of IS1096, Journal of Bacteriology, Dec. 1991, vol. 173, No. 24, pp. 7772-7780.
Jacobs, Jr., et al., Genetic Systems for Mycobacteria, Methods in Enzymology, vol. 204, pp. 537-555, 1991.
Jacobs, et al., Development of BCG as a Recombinant Vaccine Vehicle, Curr. Topics in Microbiology & Immunology, 155, pp. 153-160 (1990).
Kalpana, et al., Insertional Mutagenesis and Illegitimate Recombination in Mycobacteria, Proc. Natl. Acad. Sci., 88, pp. 5433-5437, Jun. 1991.
Ingraham, et al., eds.,Eschericia Coliand Salomella Typhimurium—Cellular and Molecular Biology, vol. 1, American Society for Microbiology, pp. x and xi, 1987—Table of Contents Only.
Lugosi, et al., Genetic Transformation of BCG, Tubercle, 70, pp. 159-170 (1989).
Hayes, et al., Genetic of Bacteria and Their Viruses, 2nd Ed., John Wiley & Sons, pp. 120-124 (1968).
England, et al., IS900—Promoted Stable Integration of a Foreign Gene into Mycobacteria, Molecular Microbiology, 5(8), pp. 2047-2052, 1991.

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