Characterization of a highly negative and labile binding protein induced in Euglena gracilis by cadmium

Journal Article · Sat Mar 01 00:00:00 EST 1986 · Environ. Health Perspect.; (United States)

DOI:https://doi.org/10.1289/ehp.866577· OSTI ID:5382356

Gingrich, D J; Weber, D N; Shaw, C F; Garvey, J S; Petering, D H

The physiochemical properties and physiological significance of the cadmium-binding protein (CdBP) of the algae Euglena gracilis have been studied. Following in vivo exposure of cells to 0.4 or 1.3 ..mu..g/mL of Cd/sup 2 +/, all the cytosolic Cd is bound to high molecular weight species. At 4.7 ..mu..g/mL, appreciable CdBP has formed in cells grown under illumination or in the dark. The large pool of very low molecular weight zinc species previously reported is increased when cells are exposed to high cadmium levels. Two distinct species, BP-1 and BP-2 are resolved by ion-exchange chromatography on DEAE-Sephadex. Unusually high conductivities are required to displace them, indicating that they are very negatively charged proteins at pH 8.6. The pH for half-titration of bound Cd/sup 2 +/ is between 5 and 6. Neither form of the CdBP cross-reacts with antibodies to rat liver metallothionein (MT) antibodies. The structural, chemical, and functional differences between the Euglena CdBPs and mammalian MTs are discussed. When cells are exposed to high levels of Cu, a CuBP is induced, and the very low molecular weight zinc band is depleted.

• Research Organization: Univ. of Wisconsin, Milwaukee
• OSTI ID: 5382356
• Journal Information: Environ. Health Perspect.; (United States), Vol. 65
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
CADMIUM CHLORIDES
BIOLOGICAL EFFECTS
COPPER COMPOUNDS
EUGLENA
PHYSIOLOGY
METALLOPROTEINS
BIOSYNTHESIS
CHEMICAL ACTIVATION
ION EXCHANGE CHROMATOGRAPHY
MOLECULAR WEIGHT
ALGAE
CADMIUM COMPOUNDS
CADMIUM HALIDES
CHLORIDES
CHLORINE COMPOUNDS
CHROMATOGRAPHY
HALIDES
HALOGEN COMPOUNDS
MASTIGOPHORA
MICROORGANISMS
ORGANIC COMPOUNDS
PLANTS
PROTEINS
SEPARATION PROCESSES
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS
UNICELLULAR ALGAE
560302* - Chemicals Metabolism & Toxicology- Microorganisms- (-1987)
550200 - Biochemistry