(full paper is archived in the Miller Library)
Title: The effect of anthropogenic organic pollution on glutathione S-transferase activity in the bay mussel, Mytilus galloprovincialis
Student Author(s): Uraiqat, Carina
Faculty Advisor(s): Somero, George
Location: Final Papers Biology 175H
Date: June 2000
Abstract: In order to measure organic pollutants and heavy metals in coastal waters, previous studies have directly assayed for these compounds in tissues of bioaccumulators such as Mytilus galloprovincialis. In contrast, this study measured the activity of the detoxification enzyme glutathione S-transferase (GST) in the digestive gland of M. galloprovincialis as a bioindicator of the state of organic pollution at three sites in the San Francisco and Monterey Bays with varying pollutant levels. Glutathione S-transferase activity was measured through the conjugation of 1-chloro-2,4-dinitrobenzene (CDNB) to reduced glutathione (GSH) to form CDNB-SH, at a wavelength of 340 nm. The activity data were collected in milliabsorbance units/min and were normalized by dividing by total tissue wet weight. Activity was highest in M. galloprovincialis from the most polluted site, Moss Landing (0.0573 ± 0.0226 mAbs/min/g tissue), intermediate in specimens from the Palo Alto site (0.0327 ± 0.0140 mAbs/min/g tissue), and lowest in samples from the least polluted site, Monterey Marina (0.0228 ± 0.0068 mAbs/min/g tissue, ANOVA p = 3.8 x 10-6). Organisms from Moss Landing also had greater digestive gland masses per total tissue mass and have higher protein concentrations than organisms from less polluted sites. Mytilus galloprovincialis was transplanted from polluted water at Moss Landing into pristine seawater and GST activity was measured over 30 days. There was a significant decrease in GST activity with reduced exposure to organic pollutants.