title: A novel selenocystine-accumulating plant in selenium-mine drainage area in Enshi, China.
abstract: Plant samples of Cardamine hupingshanesis (Brassicaceae), Ligulariafischeri (Ledeb.) turcz (Steraceae) and their underlying top sediments were collected from selenium (Se) mine drainage areas in Enshi, China. Concentrations of total Se were measured using Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS) and Se speciation were determined using liquid chromatography/UV irradiation-hydride generation-atomic fluorescence spectrometry (LC-UV-HG-AFS). The results showed that C. hupingshanesis could accumulate Se to 239±201 mg/kg DW in roots, 316±184 mg/kg DW in stems, and 380±323 mg/kg DW in leaves, which identifies it as Se secondary accumulator. Particularly, it could accumulate Se up to 1965±271 mg/kg DW in leaves, 1787±167 mg/kg DW in stem and 4414±3446 mg/kg DW in roots, living near Se mine tailing. Moreover, over 70% of the total Se accumulated in C. hupingshanesis were in the form of selenocystine (SeCys2), increasing with increased total Se concentration in plant, in contrast to selenomethionine (SeMet) in non-accumulators (eg. Arabidopsis) and secondary accumulators (eg. Brassica juncea), and selenomethylcysteine (SeMeCys) in hyperaccumulators (eg. Stanleya pinnata). There is no convincing explanation on SeCys2 accumulation in C. hupingshanesis based on current Se metabolism theory in higher plants, and further study will be needed.
authors.affiliation: Jiangsu Bio-Engineering Research Centre of Selenium, Suzhou, Jiangsu, China ; School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui, China. yuanli@mail.ustc.edu.cn
authors.forename: Linxi
authors.initials: L
authors.lastname: Yuan
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Zhi-Qing
authors.initials: ZQ
authors.lastname: Lin
authors.forename: Gary
authors.initials: G
authors.lastname: Banuelos
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Xuebin
authors.initials: X
authors.lastname: Yin
mesh_terms: D001673:Biodegradation, Environmental; D001947:Breeding; D002681:China; D008906:Mining; D009928:Organ Specificity; D010944:Plants / Q000378:metabolism*; D012643:Selenium / Q000302:isolation & purification / Q000378:metabolism*; D017279:Selenocysteine / Q000378:metabolism*
chemical_list: D017279:Selenocysteine; D012643:Selenium