TY - JOUR
T1 - A compilation of in vitro rate and affinity values for xenobiotic biotransformation in fish, measured under physiological conditions
AU - Fitzsimmons, Patrick N.
AU - Lien, Gregory J.
AU - Nichols, John W.
PY - 2007/5
Y1 - 2007/5
N2 - Scientific literature from the past 25 years was searched to obtain in vitro biotransformation rate and affinity data for fish. To maximize the environmental relevance of this dataset, we focused on studies conducted at multiple substrate concentrations, and established acceptance criteria with respect to assay temperature and pH. Altogether, enzyme rate and affinity parameters are provided for 43 species and 77 compounds. In all but three instances, the reported reactions exhibited saturation at high substrate concentrations and could be used to calculate Michaelis-Menten rate (Vmax) and affinity (Km) constants. Most of this information was obtained using in vitro systems derived from liver tissue. Information from non-hepatic tissues was included, however, to provide a basis for comparisons among tissues. Where possible, in vitro enzyme parameters were examined to compare: (1) hepatic metabolism of a common substrate within a species, (2) hepatic metabolism of common substrates by different species, and (3) metabolism of a common substrate by different tissues of one species. Comparisons within species highlight a number of factors that may substantially influence xenobiotic metabolism in fish including gender, life stage, and acclimation temperature. Limited data suggest that Vmax and Km for the same reaction may vary by up to three orders of magnitude among species.
AB - Scientific literature from the past 25 years was searched to obtain in vitro biotransformation rate and affinity data for fish. To maximize the environmental relevance of this dataset, we focused on studies conducted at multiple substrate concentrations, and established acceptance criteria with respect to assay temperature and pH. Altogether, enzyme rate and affinity parameters are provided for 43 species and 77 compounds. In all but three instances, the reported reactions exhibited saturation at high substrate concentrations and could be used to calculate Michaelis-Menten rate (Vmax) and affinity (Km) constants. Most of this information was obtained using in vitro systems derived from liver tissue. Information from non-hepatic tissues was included, however, to provide a basis for comparisons among tissues. Where possible, in vitro enzyme parameters were examined to compare: (1) hepatic metabolism of a common substrate within a species, (2) hepatic metabolism of common substrates by different species, and (3) metabolism of a common substrate by different tissues of one species. Comparisons within species highlight a number of factors that may substantially influence xenobiotic metabolism in fish including gender, life stage, and acclimation temperature. Limited data suggest that Vmax and Km for the same reaction may vary by up to three orders of magnitude among species.
KW - Affinity
KW - Biotransformation
KW - Enzymes
KW - Fish
KW - Rate
UR - http://www.scopus.com/inward/record.url?scp=34247547874&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34247547874&partnerID=8YFLogxK
U2 - 10.1016/j.cbpc.2006.12.011
DO - 10.1016/j.cbpc.2006.12.011
M3 - Review article
C2 - 17360241
AN - SCOPUS:34247547874
SN - 1532-0456
VL - 145
SP - 485
EP - 506
JO - Comparative Biochemistry and Physiology - C Toxicology and Pharmacology
JF - Comparative Biochemistry and Physiology - C Toxicology and Pharmacology
IS - 4
ER -