Cadmium-detoxification in the earthworm Enchytraeus: specific expression of a putative aldehyde dehydrogenase.
The ubiquitous earthworm Enchytraeus buchholzi is provided with a very effective, but still unknown, mechanism of Cadmium (Cd)-detoxification, a central role in which has been ascribed to the Cd-inducible crp-gene encoding a novel cysteine-rich, non-metallothionein 25 kDa protein. This study identifies another Cd-responsive gene by differential screening of a cDNA-library constructed from Cd-exposed E. buchholzi. The isolated cDNA-clone designated Ebaldh encodes a putative aldehyde dehydrogenase. Northern blot analysis shows that the Ebaldh-expression is strongly enhanced by Cd, but remains unaffected by other stressors such as Zn, Hg, and H2O2. This Cd-specificity of Ebaldh suggests that Cd-detoxification in E. buchholzi requires low intracellular concentrations of aldehydes which are known to target sulfhydryl groups thus inactivating the Cd-binding capacity of CRP.
Willuhn
J
J
Division of Molecular Parasitology, Heinrich-Heine-Universitaet Duesseldorf, Germany.
Schmitt-Wrede
H P
HP
Otto
A
A
Wunderlich
F
F
D000444:Aldehyde Dehydrogenase / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001673:Biodegradation, Environmental; D002104:Cadmium / Q000378:metabolism*; D018076:DNA, Complementary; D008969:Molecular Sequence Data; D009835:Oligochaeta / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D012333:RNA, Messenger; D002104:Cadmium; D000444:Aldehyde Dehydrogenase