Isolation and characterization of a Cd-binding protein from Allolobophora caliginosa (Annelida, Oligochaeta): distinction from metallothioneins.
1. One Cd-binding peak was detected after gel filtration chromatography on Sephadex G75 in an extract from Allolobophora caliginosa contaminated with Cd. 2. Two subsequent cation-exchange chromatographies allowed the isolation of a Cd-binding protein which was called Cd-BP14. This protein is a monomer with a molecular weight of 14 kDa and has an isoelectric point of 6.5. 3. Amino acid analysis showed the presence of a high level of aromatic amino acids and a lack of cysteine. 4. On the basis of these results we conclude that Cd-BP14 is different from metallothioneins described in mammals or other invertebrates.
Nejmeddine
A
A
Université Cadi Ayaad, Faculté des Sciences de Marrakech (I), Laboratorie d'Ecotoxicologie, Morocco.
Sautiere
P
P
Dhainaut-Courtois
N
N
Baert
J L
JL
D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003545:Cysteine / Q000032:analysis*; D004591:Electrophoresis, Polyacrylamide Gel; D007525:Isoelectric Focusing; D008668:Metallothionein / Q000032:analysis* / Q000302:isolation & purification; D008970:Molecular Weight; D009835:Oligochaeta / Q000737:chemistry*
D000596:Amino Acids; C004203:cadmium-binding protein; D008668:Metallothionein; D003545:Cysteine