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On the transformation of coliform types, proper and irregular forms
Zentralblatt Fur Bakteriologie, Parasitenkunde, Infektionskrankheiten Und Hygiene. Zweite Naturwissenschaftliche Abteilung: Mikrobiologie Der Landwirtschaft Der Technologie Und Des Umweltschutzes
|January 1, 1979
Summary
Researchers induced physiological and biochemical changes in Escherichia coli (E. coli) strains, transforming regular and irregular forms. These transformations were achieved through UV irradiation and selective growth conditions, altering E. coli
Area of Science:
- Microbiology
- Bacteriology
- Molecular Biology
Background:
- Escherichia coli (E. coli) exists in regular and irregular forms with distinct biochemical profiles.
- Understanding the relationship and potential transformations between these forms is crucial for microbial identification and environmental monitoring.
Purpose of the Study:
- To induce physiological and biochemical transformations in E. coli strains.
- To investigate the relationship between regular and irregular coliforms.
- To explore methods for altering E. coli strain characteristics.
Main Methods:
- Culturing E. coli strains (E. coli I, E. coli III) in a basal synthetic medium with supplements (sodium pyruvate, glucose, yeast extract, peptone).
- Inducing biochemical pattern changes using IMViC tests and growth at 44.5°C.
- Applying ultra-violet (UV) irradiation to E. coli I.
- Training E. coli III for heat resistance and growth in MacConkey broth.
- Utilizing phage typing for verifying relationships between coliforms.
Main Results:
- Biochemical transformations were induced, altering E. coli strains between regular and irregular forms.
- UV irradiation transformed E. coli I into a methyl-red negative strain.
- E. coli III was trained to produce acid and gas at 44.5°C.
- E. coli I was transformed to mimic Geldreich's untyped form 1 via UV irradiation.
- E. coli III exhibited E. coli I's biochemical reactions after heat resistance training.
- Phage typing confirmed relationships between regular and irregular coliforms, analyzed by lytic activity and efficiency of plating.
Conclusions:
- Physiological and biochemical transformations between regular and irregular E. coli forms are achievable through environmental manipulation and specific treatments.
- UV irradiation and selective culturing are effective methods for inducing significant changes in E. coli characteristics.
- Phage typing provides a valuable tool for elucidating the taxonomic and phylogenetic relationships among coliform bacteria.