Regulation of ammonia uptake inAspergillus nidulans

Summary The ammonia uptake inA. nidulans was found to be linear for about 20 min, and was proportional up to 1.5 mg/ml dry cell density. The transport of ammonia does not involve energy. Normal and biotin deficientA. nidulans showed an identical K_m-values of 10.26×10^–5 M ammonia for uptake. The uptake of ammonium ion has been shown to be regulated by the intracellular concentration of ammonia.Acknowledgment. The award of research fellowship by the Govt of India, Department of Atomic Energy, Bombay, to JDD is acknowledged.