Abstract
The toxicity of copper on a sole nitrate medium containing KH2PO4 as the phosphate source has been studied inNeurospora crassa. Iron counteracted the copper toxicity by suppressing the copper uptake and restored complete growth at a lower iron-copper molar ratio. Nitrite reductase activity was inhibited (75%) in copper toxic cultures, while the nitrate reductase activity was unaltered. Nitrite accumulated in the medium; this indicated decreased conversion of nitrate to ammonia. Alanine transaminase was also inhibited in copper toxicity, resulting in an accumulation of keto acids. Iron could restore the nitrite reductase and the transaminase activities to about 70% of the control value. The accumulation of both nitrite and keto acids disappeared under conditions of reversal of copper toxicity by iron.
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Rao, S., Subramanyam, C. & Venkateswerlu, G. Nitrogen metabolism in the blue mycelia ofNeurospora crassa isolated from copper toxic cultures. Current Microbiology 10, 79–83 (1984). https://doi.org/10.1007/BF01575763
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DOI: https://doi.org/10.1007/BF01575763