title: Mercury uptake and removal by Euglena gracilis.
abstract: The uptake and removal of mercury (added as HgCl2) from the culture medium by Euglena gracilis was studied. In cultures initiated in the light, cells accumulated a small fraction of the added heavy metal (5-13%). Mercury was both biologically and nonbiologically volatilized, and cell growth was partially inhibited; under these conditions the glutathione content was 3.2 nmol/10(6) cells. In contrast, in cultures initiated in the dark, mercury uptake by cells was two to three times higher, biological volatilization remained unchanged and nonbiological volatilization and growth were negligible; the glutathione content diminished to 1.4 nmol/10(6) cells. Biological mercury volatilization depended on cell density and metal concentration, but was light-independent. Thus, volatilization of mercury by Euglena appeared not to be an effective mechanism of resistance, whereas a high intracellular level of glutathione and a low mercury uptake seemed necessary for successful tolerance.
authors.affiliation: Departamento de Bioquímica, Instituto Nacional de Cardiología, México. sdevars@hotmail.com
authors.forename: S
authors.initials: S
authors.lastname: Devars
authors.forename: C
authors.initials: C
authors.lastname: Avilés
authors.forename: C
authors.initials: C
authors.lastname: Cervantes
authors.forename: R
authors.initials: R
authors.lastname: Moreno-Sánchez
mesh_terms: D000818:Animals; D003470:Culture Media; D005056:Euglena gracilis / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D005978:Glutathione / Q000032:analysis / Q000378:metabolism; D008628:Mercury / Q000032:analysis / Q000378:metabolism*; D013347:Subcellular Fractions / Q000737:chemistry; D014835:Volatilization
chemical_list: D003470:Culture Media; D008628:Mercury; D005978:Glutathione