2020同步年報

050 ACTIVITY REPORT 2020 Y u-Ting Liu (National Chung Hsing University) and her collaborators recently revealed molecular mechanisms for the removal of Pb by Cyanidiales. Such releases of heavy metals due to anthropogenic activity have threatened the health of ecosystems. Lead (Pb) is a particularly dangerous chemical substance as it accumulates in not only organ- isms but entire food chains. Once human beings become exposed to Pb, the brain and kidneys, of both adults and children, might be damaged. To improve the situation caused by release of Pb into environments, especially in acid wastewater and soil systems, the team of Liu and her coworkers developed Cyanidiales as a potential biomate- rial for the removal of Pb. Cyanidiales (red microalgae) are capable of surviving in extreme environments (20−56 o C; pH 0.5−5.0) with concentrated metals, allowing them to serve as promising green materials applied in metal remediation. An understanding of their mechanisms of metal detox- ification has been limited. This work is hence the first to determine the capacity and related mechanisms of sorption of Pb(II) ions on Cyanidiales including Galdieria maximum Fig. 1 : 2-D images for (a,b) Gm, (c,d) Cm, and (e,f) Cc with and without sorbed Pb. Sorbed Pb was 38, 214 and 298 mg g -1 on Gm, Cm and Cc. [Reproduced from Ref. 1] (a) Inorganic species (b) Organic species (c) Results of LCF analyses (d) Protein secondary structure in vivo of cell Fig. 2 : Pb L III -edge X-ray absorption spectra of (a) inorganic and (b) organic Pb species as standard references used in linear combination fitting (LCF). (c) Results of LCF analyses to determine the Pb species on Gm, Cm and Cc on which Pb was sorbed at 38, 214 and 298 mg g -1 , respectively. (d) Ratios of signal intensity for an α-helix (1652 cm -1 ) to a parallel β-strand (1631 cm -1 ) on protein secondary structure as a function of amount of Pb sorbed on Gm, Cm and Cc. [Reproduced from Ref. 1] Lead (Pb) Contamination Improved by Cyanidiales Molecular mechanisms for the removal of Pb by Cyanidiales: a potential biomaterial applied in thermo-acidic conditions.