Methylammonium (ammonium) uptake in a glutamine auxotroph of the cyanobacterium Anabaena cycadeae

FEBS Letters

Singh, D.T.²  Singh, H.N.²  Rai, A.N.¹ 

[1] Department of Biochemistry, North-Eastern Hill University, Shillong 793014, India;School of Life Sciences, University of Hyderabad, Hyderabad 500134, India

关键词: Ammonium transport;    Anabaena cycadeae;    Cyanobacteria;    GS;    glutamine synthetase;    MSX;    L-methionine-DL-sulphoximine;   

DOI  :  10.1016/0014-5793(85)81337-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Methylammonium uptake was studied in a glutamine auxotroph of the cyanobacterium Anabaena cycadeae lacking glutamine synthetase activity. The uptake pattern was found to be biphasic, consisting of an initial fast phase lasting up to 60 s followed by a slower second phase. When cells were preincubated with L-meth-ionine-DL-sulphoximine, an irreversible inhibitor of glutamine synthetase activity, the second uptake phase was abolished although the first phase was unaffected. Since the glutamine auxotroph did not have any glutamine synthetase activity the inhibition of the second phase by L-methionine-DL-sulphoximine could not have been due to the inhibition of glutamine synthetase activity. Thus, it is suggested that the two uptake phases may represent two different ammonium transport systems, the second one being sensitive to L-meth-ionine-DL-sulphoximine.

【 授权许可】

Unknown