SULT1A1, SULT1B1, and SULT1E1 are the major phenol sulfotransferases expressed in human liver, with SULT1A1 (also known as ST1A3) found at the highest concentration (Honma et al.
We genotyped the HL cytosol fractions used in this study, with respect to the common SULT1A1 polymorphic variants, to examine the possibility that OH-PCBs would affect their activity differently.
We found that the HL cytosols used were from individuals with different SULT1A1 genotypes, as determined by PCR amplification of the region of the SULT1A gene flanking the polymorphic base pair.
We observed substrate inhibition in HL cytosol and with SULT1A1 and SULT1E1, but not with SULTIA3 or SULT1B1.
2002) and that a compound structurally related to OH-PCBs, 2,4,4'-trichloro-2'hydroxydiphenyl ether (triclosan), inhibited sulfonation and glucuronidation of 3-OHBaP and other substrates in HL cytosol and with SULT1A1, SULT1B1, and SULT1E1 (Wang et al.
We could not discern any other clear relationship of inhibitory potency with structural features or with physicochemical properties of the OH-PCBs in this relatively small series of compounds, with cytosol or the two expressed SULT1A1 enzymes.
SULT1B1, the thyroid hormone sulfotransferase, catalyzed the sulfonation of 3-OH-BaP; however, OH-PCBs that were potent inhibitors of SULT1A1 were only weak inhibitors of the SULT1Bl-catalyzed reaction.