Induction of siderophore activity in Anabaena spp. and its moderation of copper toxicity.

摘要: Growth of Anabaena sp. strain 7120 (in the absence chelators or added iron) was inhibited by addition 2.1 to 6.5 microM copper and abolished concentration 10 higher. When chelated schizokinen (the siderophore produced this organism in response iron starvation), toxic effects were eliminated. Analysis culture filtrates showed that cupric remains medium, thereby lowering amount taken up cells. Although actively transports ferric schizokinen, it apparently does not recognize complex. Thus, is protected from toxicity under conditions which being produced. For cells grown low iron, accumulation extracellular observed parallel cell growth continue well into stationary phase. The actual status monitored using uptake velocity as an assay. Cultures on 0.1 found be severely limited upon reaching phase, thus explaining continued production schizokinen. These data show system spp. has developed primarily a starvation additional functions such alleviation allelopathic inhibition other algal species are merely secondary benefits.