This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Web of Science (20) Citing Articles via Google Scholar Google Scholar Articles by Gearing, P. Articles by Parker, P. L. Search for Related Content PubMed PubMed Citation Articles by Gearing, P. Articles by Parker, P. L. Agricola Articles by Gearing, P. Articles by Parker, P. L.

Articles

Biochemical Effects of Technetium-99-Pertechnetate on Microorganisms ¹

^a The University of Texas Marine Science Institute, Port Aransas, Texas 78373

The biochemical effects of technetium-99 as pertechnetate (TcO₄^–) were investigated in a variety of microorganisms (a nonsulfur purple bacterium, five blue-green algae, a protozoan, a diatom, two heterotrophic bacteria, a red alga and two green algae). Sensitivity to pertechnetate as measured by growth ranged from marked inhibition at 1 µg Tc/ml (nonsulfur purple bacterium) to no effect at 600 µg Tc ml (both green algae). No correlation between organism type and growth susceptibility to pertechnetate was apparent. The blue-green alga, Agmenellum quadruplicatum strain PR-6, bound technetium-99 to a level of 3 µg/mg dry weight cells (from medium containing 1.5 mM pertechnetate) in the light, but little or none in the dark; cell death occurred only with uptake. Addition of TcO₄^– to the medium caused a rapid but temporary increase in ATP levels of PR-6 (in the light only) and Tetrahymena pyriformis strain WH14. Respiration of organisms WH14 and Bacillus subtilis and photosynthesis of organism PR-6 were immediately slowed by the introduction of pertechnetate. Technetium as pertechnetate has a possible biochemical effect on cells, unrelated to its radioactivity or to a general oxidation effect.