Mutagenesis of AS52 cells by low concentrations of lead(II) and mercury(II)

The effect of iron on the biological activities of erionite and mordenite

“…Since the gpt gene is not essential for growth or survival of AS52 cells, it is possible to isolate mutants containing a variety of mutations, including: point, interchromosomal deletions, mitotic recombinations, gene -chromosomal conversions and multilocus deletions. We, as well as others, have demonstrated that AS52 cells can be used to determine molecular and mechanistic features associated with mutagenesis in mammalian cells (Tindall et al, 1984(Tindall et al, , 1986(Tindall et al, , 1987Tindall and Stankowski, 1989;Hsie et al, 1990;Ariza and Williams, 1996;Ariza et al, 1998).…”

“…AS52 cells were maintained, as described previously (Ariza and Williams, 1996), at 37 jC in a humidified 5% CO 2 environment in F-12 medium, which contains 3 AM Fe 2 SO 4 Á7H 2 0, supplemented with 5% (v/v) heat-inactivated DFBS and MPA additives (10 Ag/ml mycophenolic acid, 25 Ag/ml adenine, 50 AM thymidine, 250 Ag/ml xanthine and 3 AM aminopterin).…”

“…Mutagenesis was performed with minor modifications of the procedures that we have described previously (Ariza and Williams, 1996). Briefly, AS52 cells (10 6 ) were exposed to various concentrations of zeolites (expressed as Ag/cm 2 of culture dish) with and without added soluble iron (ferrous chloride 1 -20 AM) for 24 h in Ham's F-12 medium containing 5% DFBS.…”

“…Cytotoxicity and relative cloning efficiency (RCE) was determined, as we have described (Ariza and Williams, 1996). Briefly, cytotoxicity is determined 24 h after initiation of treatment, by determining the RCE of the treated population when compared to nontreated controls.…”

“…The historical spontaneous mutation frequency of AS52 cells in our laboratory is 10.5 F 2.7 TG r mutants/10 6 clonable cells. As a positive control, AS52 cells were treated with ethylmethanesulfonate (EMS) as described previously (Tindall et al, 1984;Ariza and Williams, 1996). The mutation frequency under these conditions was 346.7 F 22.4 TG r mutants/10 6 clonable cells.…”