title: Phytochelatin synthesis in Dunaliella salina induced by arsenite and arsenate under various phosphate regimes.
abstract: This study investigated the dynamic variations in thiol compounds, including cysteine (Cys), glutathione (GSH), and phytochelatins (PCs), in Dunaliella salina samples exposed to arsenite [As(III)] and arsenate [As(V)] under various phosphate (PO43-) regimes. Our results showed that GSH was the major non-protein sulfhydryl compound in D. salina cells. As(III) and As(V) induced PC syntheses in D. salina. PC2, PC3, and PC4were all found in algal cells; the PC concentrations decreased gradually while exposed to As for 3 d. The synthesis of PC2-3was significantly affected by As(III) and As(V) concentrations in the cultures. More PCs were detected in the As(V)-treated algal cells compared with the As(III) treatment. PC levels increased with As(III)/As(V) amount in the medium, but remained stable after 112μgL-1As(V) exposure. In contrast, significant (p<0.001) positive correlations were observed between PC synthesis and intracellular As(III) content or As accumulation in As(III)-treated algal cells during the 72-h exposure. PO43-had a significant influence on the PC synthesis in algal cells, irrespective of the As-treated species. Reductions in As uptake and subsequent PC synthesis by D. salina were observed as the PO43-concentration in the growth medium increased. L-Buthionine sulfoximine (BSO) differentially influenced PC synthesis in As-treated D. salina under different extracellular PO43-regimes. Overall, our data demonstrated that the production of GSH and PCs was affected by PO43-and that these thiols played an important role in As detoxification by D. salina.
authors.affiliation: Jiangsu Provincial Key Laboratory of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China; Institute of Food Quality and Safety, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Demonstration Laboratory of Element and Life Science Research, Laboratory Centre of Life Science, College of Life Science, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Chunhua
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Jiangsu Provincial Key Laboratory of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Yanheng
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Jiangsu Provincial Key Laboratory of Marine Biology, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: yingge711@njau.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Ge
mesh_terms: D020418:Algal Proteins / Q000378:metabolism*; D001149:Arsenates / Q000633:toxicity*; D018053:Arsenites / Q000633:toxicity*; D019328:Buthionine Sulfoximine / Q000494:pharmacology; D000460:Chlorophyta / Q000187:drug effects* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism; D058086:Microalgae / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism*; D054811:Phytochelatins / Q000378:metabolism*
chemical_list: D020418:Algal Proteins; D001149:Arsenates; D018053:Arsenites; D004791:Enzyme Inhibitors; D010710:Phosphates; D019328:Buthionine Sulfoximine; D054811:Phytochelatins; D005978:Glutathione
keywords: Arsenate; Arsenite; Dunaliella salina; Phosphate; Thiol compounds