FIG. 3.

Oxygen uptake rates with various compounds by resting-cell suspensions of S. xenophagum grown in the presence and the absence of technical nonylphenol. Specific oxygen uptake rates were corrected for endogenous oxygen uptake (3.1 to 8.9 nmol O₂ × min⁻¹ × mg cells [dry weight]⁻¹) and expressed as percentages of the specific rate of O₂ consumption of the induced cells caused by 4-NP₁₁₂ (65.4 nmol O₂ × min⁻¹ × mg cells [dry weight]⁻¹). The data points represent the mean values of at least two measurements, and the corresponding standard deviations are expressed with error bars. The following substrates had an activity lower than 4% and were not included in the figure: p-cresol, 4-ethylphenol, 4-n-propylphenol, 4-isopropylphenol, 4-n-nonylphenol, 4-hydroxybenzoic acid, 4-hydroxybenzonitrile, 4-methoxyphenol, 4-n-octyloxyphenol, 4-fluorophenol, 4-chlorophenol, 4-nitrophenol, catechol, resorcinol, and p-benzoquinone.