Bp. Bradley et al., COMPLEX MIXTURE ANALYSIS USING PROTEIN EXPRESSION AS A QUALITATIVE AND QUANTITATIVE TOOL, Environmental toxicology and chemistry, 13(7), 1994, pp. 1043-1050
Some proteins in organisms exposed to chemicals in stressful amounts o
r toxic concentrations show increased expression; others show decrease
d expression. These inducible and repressible proteins together potent
ially provide qualitative and quantitative diagnoses of components in
complex mixtures of chemicals. We examined sets of proteins synthesize
d by Daphnia magna after exposure to mixtures of a cationic polyamide
epichlorhydrin adduct (Kymene) and a combined assortment of water-extr
actable substances from chemi-thermal-mechanical pulp (CTMP) in lab wa
ter. Proteins were identified, after extracting from Daphnia magna, by
gel filtration and silver staining, or by radiolabeling and then gel
separation. Patterns of proteins induced by Kymene(R) and by CTMP extr
acts were distinguishable in lab water, but there was interaction betw
een them. The method of identifying and quantifying Kymene, however, w
as successful using lab simulations of mixtures. The method was tested
using wastewater samples from a paper manufacturing plant. Kymene cou
ld be detected against variable levels and types of additional substan
ces. But, again, there was interference, perhaps due to Kymene binding
to other anionic polymers sometimes present in the samples. Interpret
ations from analyses of protein expression were consistent with result
s from sublethal Ceriodaphnia dubia assays.