Studying Pathogenic Organisms a5 Look at other similar members of the same genus; for example M, smegmatis vs M tuberculosis M, smegmatis is faster-growing; methods may be applicable to M. tuberculosis BIOL 533 7 Lecture three
BIOL 533 7 Lecture Three Studying Pathogenic Organisms • Look at other, similar members of the same genus; for example: – M. smegnatis vs. – M. tuberculosis M. smegnatis is faster-growing; methods may be applicable to M. tuberculosis
Studying Pathogenic Organisms a5 Approaches for identifying virulence factor and proving its importance in causing disease Biochemical Genetic Immunological Best to combine approaches BIOL 533 Lecture three
BIOL 533 8 Lecture Three Studying Pathogenic Organisms • Approaches for identifying virulence factor and proving its importance in causing disease: – Biochemical – Genetic – Immunological • Best to combine approaches
Biochemical/Immunological Purify molecule and study in vitro Yields detailed information about Cofactors General physical properties BIOL 533 Lecture three
BIOL 533 9 Lecture Three Biochemical/Immunological • Purify molecule and study in vitro • Yields detailed information about – Cofactors – General physical properties
Biochemical/Immunological TWo limitations Molecule must be assayable: most applicable if know product and function Measurements on isolated molecules may not accurately reflect function in intact bacterium Prove function in vivo, have to take either genetic or immunological approach BIOL 533 Lecture three
BIOL 533 10 Lecture Three Biochemical/Immunological • Two limitations: – Molecule must be assayable; most applicable if know product and function – Measurements on isolated molecules may not accurately reflect function in intact bacterium • Prove function in vivo; have to take either genetic or immunological approach
Immunological Determine whether ab to bacterial product are protective in infected animals Possible problem Ab to bacterial surface molecules might prevent infection by opsonizing or enhancing complement action rather than inactivating virulence factor BIOL 533 Lecture three
BIOL 533 11 Lecture Three Immunological • Determine whether Ab to bacterial product are protective in infected animals • Possible problem: – Ab to bacterial surface molecules might prevent infection by opsonizing or enhancing complement action rather than inactivating virulence factor