Lemna system

New transgenic production systems are emerging that possess the potential to become industrially successful (e.g., transgenic moss, lemna, fungal or yeast expression systems, transgenic animals and... 

Leachate Lemna root Lentic system Lethal... 

Organization for Economic Cooperation and Development (OECD) (1999a) Draft Guideline for the Testing of Chemicals. Section 2 - Effects on Biotic Systems. Lemna spp. Growth Inhibition Test. OECD, Paris. 

Fig. 2. Efifect of growii Lemna at various concentrations of sulfate on the short-term sulfate uptake rate. Uptake was measured at low concentrations of sulfate (2 and 20 fiM) to ascertain the rate of the high-affinity (low K ) uptake system and at a high concentration of sulffite (25 mM) from which the nonsaturating uptake component was calculated. (From Datko and Mudd, 1984a.)...

The level of sulfotransferase in Lemna and in Phaseolus vulgaris is also subject to strong inhibition by gaseousH2S(Brunoldand Schmidt, 1976,1978 Wyss and Brunold, 1979). However, the extractable acti vity of cysteine synthase is not similarly affected. Removal of H2S firom the gas phase results in rapid restoration of activity which, based on a study of labeling of the enzyme (von Arb and Brunold, 1980), was attributed to synthesis ofthe enzyme de novo. HjS also inhibits the level of APS sulfotransferase in cell suspension cultures of Nicotiana sylvestris in this tissue neither the ATP-sulfiirylase or cysteine synthase activity was affected by H2S or cysteine (Brunold etal., 9Sl). Importantly, the inhibition of APS sulfotransferase by H2S was correlated with an enhanced level of cysteine, suggesting that the H2S inhibition could have been mediated via this reaction product. Uptake of exogenous sulfate was also inhibited by H2S in this system (Brunold et al., 1981). 

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