title: Isolation of antibiotic-resistant and antimetabolite-resistant mutants of Frankia strains EuI1c and Cc1.17.
abstract: Antibiotic-resistant and antimetabolite-resistant mutants of the nitrogen-fixing symbiotic bacterium Frankia were isolated to provide strains with genetic backgrounds amenable to genetic analysis. The lethal and mutagenic effects of ethyl methanesulfonate (EMS) and UV light on four Frankia strains were investigated. UV irradiation or EMS treatment of strain EuI1c cells resulted in the formation of two different colony types: rough and smooth. The smooth colonies were conditional sporulation mutants. In the case of EMS-induced cells of strain Cc1.17, resistance to lincomycin, ampicillin, and 5-fluorouracil occurred at a frequency of 1 x 10(-5), 1 x 10(-5), and 4 x 10(-5), respectively. The lincomycin-resistant mutants produced a yellow-tan pigment that was released into the growth medium. Resistance to tetracycline and lincomycin with EMS-induced cells of strain EuI1c occurred at a frequency of 3.2 x 10(-3) and 4.7 x 10(-4), respectively. These strains will be useful for the development of genetic methods for Frankia.
authors.affiliation: Department of Microbiology, University of New Hampshire, Durham, 03824-2617, USA.
authors.forename: Anna K
authors.initials: AK
authors.lastname: Myers
authors.forename: Louis S
authors.initials: LS
authors.lastname: Tisa
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D005020:Ethyl Methanesulfonate / Q000494:pharmacology; D040161:Frankia / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000528:radiation effects; D009154:Mutation; D014466:Ultraviolet Rays
chemical_list: D000900:Anti-Bacterial Agents; D005020:Ethyl Methanesulfonate