โ Scribed by Stewart, W. D. P. ;Lex, M.
No coin nor oath required. For personal study only.
The non-heteroeystous filamentous blue-green alga, Plectonema boryanum strain 594 reduces acetylene to ethylene, incorporates 15N 2 into cell protoplasm, and grows readily in medium free of combined nitrogen, when incubated in a gas phase without added oxygen. Cells grown in the presence of 50 mg/1 of ammonium-nitrogen do not reduce acetylene, and a concentration of 0.015 atm. CO in the gas phase inhibits nitrogenase activity completely but inhibits 14C02 incorporation by only 28o/0 . Nitrogenase activity is inhibited after 2 h treatment with 3 โข 10 -5 M DCMU and is inhibited completely in air.
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