Effect of nickel, copper, and zinc on emulsifier production and saturation of cellular fatty acids in the filamentous fungus Curvularia lunata
Effect of nickel, copper, and zinc on emulsifier production and saturation of cellular fatty acids in the filamentous fungus Curvularia lunata
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DOI：
10.1016/j.ibiod.2008.03.015
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发表时间：
2009
影响因子：
4.8
通讯作者：
K. Paraszkiewicz;P. Bernat;J. Długoński
中科院分区：
文献类型：
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作者：
K. Paraszkiewicz;P. Bernat;J. Długoński
在本研究的第一步中，评估了Ni 2+、Cu 2+和Zn 2+离子对新月弯孢菌产乳化剂菌株的毒性。在所研究的重金属中，Ni ~（2+）对C.而Zn ~（2+）的毒性最低。此外，只有Ni ~（2+），当使用在亚致死浓度（5 mM）引起一些菌丝顶端细胞裂解后，短期曝光（5 h）。在48 h培养液中，在重金属不抑制真菌生长的情况下，检测了乳化剂的产生、菌丝体和乳化剂对重金属的积累以及细胞脂肪酸的饱和度（在初始浓度为1、5和15 mM的Ni 2+、Cu 2+和Zn 2+离子的存在下，分别为）和在其中发生约50%生物量抑制的培养物中（在分别为3、10和17.5mM的初始浓度的Ni 2+、Cu 2+和Zn 2+离子存在下）。在所有研究的重金属中，只有Ni 2+离子没有诱导乳化剂的产生。与对照相比，只有生物量与Ni 2+离子处理显示出增加总脂质饱和度。这种影响主要是由于亚油酸（18：2）含量的减少与硬脂酸（18：0）含量的增加相关。探讨了Ni ~（2+）离子改变C.并对乳化剂的保护作用进行了讨论。
In the first step of this investigation the toxicity of Ni2+, Cu2+, and Zn2+ions to the emulsifier producing strain of Curvularia lunata was assessed. Among all the heavy metals studied, Ni2+ions were found to be the most toxic to C. lunata, whereas Zn2+ions exhibited the lowest toxicity. Moreover, only Ni2+, when used at sublethal concentration (5mM) caused lysis of some hyphal tip cells after a short-term exposure (5h). In the next step, emulsifier production, accumulation of heavy metals by mycelia and emulsifier as well as saturation of cellular fatty acids were examined in 48-h-old cultures where fungal growth intensity was not inhibited by heavy metals (in the presence of Ni2+, Cu2+, and Zn2+ions at the initial concentration of 1, 5, and 15mM, respectively) and in cultures where approximately 50% biomass inhibition occurred (in the presence of Ni2+, Cu2+, and Zn2+ions at the initial concentrations of 3, 10, and 17.5mM, respectively). Among all the heavy metals studied only Ni2+ions did not induce emulsifier production. As compared with the control, only biomass treated with Ni2+ions displayed an increase in total lipid saturation. This effect resulted mainly from the decrease in linoleic acid (18:2) content correlated with the increase in the amount of stearic acid (18:0). The possible mechanisms by which Ni2+ions could alter the fatty acid profile of C. lunata and the protective role of the emulsifier were also discussed.