铊在真菌亚细胞中的分布特征
Sub-cellular Distribution of Thallium in Fungus
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摘要: 将前期从铊污染区筛选得到的9株高耐受性真菌菌株用于微生物对铊的富集和亚细胞分布实验,采用酶解和差速离心法分离各亚细胞组分,并检测其中铊的质量分数.结果表明,生物富集量随着铊处理浓度上升而降低,其影响趋势与对生物量的影响趋势基本一致,最高可达7 189 mg/kg,最大富集系数为7.19.在亚细胞水平上,铊的富集优先顺序为:细胞质—细胞壁—细胞器.亚细胞水平的区隔化作用是真菌对铊的主要耐受机制,细胞质是赋存铊的主要场所(53.83%~79.45%).Abstract: This paper focused on the sub-cellular distribution of thallium in several different fungus strains.The fungus strains were isolated from the Lanmuchang thallium-mineralised area in southwest Guizhou Province,and were used in the bio-concentration experiments.The sub-cellular supernatants including cytoplasmic,cellwall and cell organelles were seperated by the differential centrifuge after treated with snailase.Resultsshow that the bio-concentration rate of thallium in the nine strains decreases with increasing thallium contents in the culture,the maximum at 7 189 mg/kg and the maximum bio-concentration factor(BCF) at 7.19.In the sub-cellular supernatants detected by ICP-OES,the majority of thallium(up to 79.45%) was found in cytoplasmic organelles,and the concentrations of thallium in the order of priority are as follows: cytoplasmic-cellwall-cell organelles.Cytoplasmic supernatant is apparently a major storage site for thallium,which is a possible detoxification of thallium by the fungus.