Effects of inorganic arsenic on growth and microcystin production of a Microcystis strain isolated from an algal bloom in Dianchi Lake,China

• 来源期刊: 科学通报(英文版)
• 学科: 地球科学
• 年，卷（期）: 2011,（22）
• 页码范围: 2337-2342
• 页数: 6页
• 分类号: X173
• 语种: 中文

摘要

Our previous data have shown that inorganic arsenic concentrations were high in Dianchi Lake,China,where Microcystis blooms often occur.To explore the relationship between arsenic and the growth of Microcystis,the effects of arsenite[As(III)]and arsenate[As(V)]on the growth and toxin production of M.aeruginosa strain FACHB 905 were tested.Results showed that M.aeruginosa FACHB 905 was tolerant to inorganic arsenic and its growth was not inhibited when the concentration of As(III)was below 10-5 mol L-1 or that of As(V)below 10-3 mol L-1.Total microcystin production was stimulated in the presence of 10-7 mol L-1 As(III)and the response of this M.aeruginosa strain to As(III)seemed to be a typical inverted U-shaped hormesis.The content increase of microcystin-LR per cell indicated that the toxicity was enhanced as M.aeruginosa FACHB 905 was exposed to As(V).Considering the relatively high concentration of inorganic arsenic in Dianchi Lake(139μg L-1 in epilimnetic water),the origin of the M.aeruginosa strain,inorganic arsenic favors survival of M.aeruginosa FACHB 905 and may stimulate its microcystin production and cellular toxicity.