A butyrylcholinesterase in the early development of the brine shrimp (Artemia salina) larvae: a target for phthalate ester embryotoxicity?
The phthalate ester insensitive blue-green algae (Synechococcus lividus) were used as a food source to extend the survival of synchronously hatched brine shrimp (Artemia salina) larvae allowing measurement of a reduced toxic response to phthalate esters at late post-hatching stages of development. The maximum acute toxicity due to di-n-butyl phthalate (DNBP) correlated with the expression of a phthalate ester-hydrolyzing enzyme. The purified enzyme was identified as a butyrylcholinesterase due to its rapid inactivation by low concentrations (10(-7)M) of diisopropyl fluorophosphate and inhibition by physostigmine (IC(50)=6 x 10(-7)M) and tetraisopropylpyrophosphoramide (I-OMPA, IC(50)=x 10(-6)M) but not by BW284c5. Apparently competition of the phthalates with the endogenous substrates of the enzyme led to development-dependent toxicity.
Acey
Roger A
RA
Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90840, USA. racey@csulb.edu
Bailey
Stacie
S
Healy
Patricia
P
Jo
Chang
C
Unger
Thomas F
TF
Hudson
Richard A
RA
D000818:Animals; D001156:Artemia / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development*; D002091:Butyrylcholinesterase / Q000378:metabolism*; D000458:Cyanobacteria / Q000378:metabolism; D004032:Diet; D004952:Esters; D007814:Larva / Q000187:drug effects / Q000378:metabolism; D015394:Molecular Structure; D010795:Phthalic Acids / Q000378:metabolism / Q000633:toxicity*
D004952:Esters; D010795:Phthalic Acids; C032279:phthalic acid; D002091:Butyrylcholinesterase