Department of Botany and Institute for Environmental Studies, University of Toronto, M5S 1A1, Toronto, Ontario, Canada.
Microb Ecol. 1988 Sep;16(2):213-31. doi: 10.1007/BF02018915.
In isolates ofEuglena mutabilis and an associated yeast from strongly acidic tundra ponds (pH 1.8-2.0) at the Smoking Hills, North West Territories (N.W.T.), and in isolates from acidic ponds in the Yukon, a remarkable degree of tolerance to a number of toxic elements and to very low pH has been found. Growth was used as a measure of tolerance. The tolerances to both low pH and to elevated metal concentrations were markedly enhanced when both organisms were present together. This mutualism occurred even betweenE. mutabilis from one field location and a yeast from another. In every field collection we made ofEuglena, the yeast was also found. The tolerances to metals are 10-100 times higher than the highest reported previously for algae, and include tolerance to some metals not elevated in the ponds from which isolations were made. Reciprocal combinations of algal-yeast partners suggest a generalized benefit of association and an increased benefit for co-selected pairs from a specific site. This algal-yeast association may be a major factor in allowing colonization of these extreme acid habitats, paralleling the cyanobacteria-bacterial associations of extremely alkaline waters.
在西北领地（N.W.T.）烟山的强酸性冻土地带池塘（pH 值 1.8-2.0）中，从变形虫（Euglena mutabilis）和与其相关的酵母中，以及在育空地区酸性池塘的分离物中，发现了对多种有毒元素和极低 pH 值的显著耐受程度。生长被用作耐受程度的衡量标准。当两种生物同时存在时，对低 pH 值和升高的金属浓度的耐受性都显著增强。这种共生关系甚至发生在来自一个野外地点的变形虫和另一种酵母之间。在我们对变形虫的每一次野外采集中，也发现了酵母。对金属的耐受性比以前报道的藻类最高水平高出 10-100 倍，并且包括对一些在进行分离的池塘中未升高的金属的耐受。藻类-酵母伙伴的相互组合表明，关联具有普遍的益处，并且来自特定地点的共同选择对具有更高的益处。这种藻类-酵母的共生关系可能是允许这些极端酸性栖息地殖民化的主要因素，与极碱性水中蓝细菌-细菌的共生关系相平行。
