Lei Wenliang, Liu Juan, Zhang Wenyong, Xu Jing, Bo Tao, Wang Zhiwen, Wang Wei
Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, China.
School of Life Science, Shanxi University, Taiyuan 030006, China.
Int J Biol Macromol. 2025 May;305(Pt 2):141166. doi: 10.1016/j.ijbiomac.2025.141166. Epub 2025 Feb 17.
HS is a crucial endogenous gaseous signaling molecule involved in various metabolic pathways and is associated with the biological response to heavy metal stress. The biomineralization of CdS serves as a critical mechanism for responding to cadmium stress and removing Cd in different organisms. CdS is also a widely utilized semiconductor material for the photocatalytic degradation of dyes. In this study, we found that cysteine synthetase 1 (TtCsa1) is involved in CdS formation under cadmium stress in Tetrahymena thermophila. TtCsa1 also catalyzed CdS formation in vitro, and the synthesized CdS material exhibited controllable particle size and photoluminescence. Concurrently, cysteine and glutathione functioned as capping agents to regulate CdS particle size. The biosynthetically produced CdS degraded 90 % of methylene blue under UV light. Furthermore, CdS-ZnS nanocomposites were synthesized by adding Zn into the CdS biosynthetic system, which decreased the size of CdS particles and increased the degradation rate of methylene blue. The results indicate that the CdS biosynthesized by TtCsa1 from Tetrahymena thermophila is effective in the photocatalytic degradation of organic dyes.
硫化氢是一种关键的内源性气体信号分子，参与多种代谢途径，并与对重金属胁迫的生物反应相关。硫化镉的生物矿化是不同生物体应对镉胁迫和去除镉的关键机制。硫化镉也是一种广泛用于光催化降解染料的半导体材料。在本研究中，我们发现嗜热四膜虫中的半胱氨酸合成酶1（TtCsa1）在镉胁迫下参与硫化镉的形成。TtCsa1在体外也催化硫化镉的形成，合成的硫化镉材料表现出可控的粒径和光致发光。同时，半胱氨酸和谷胱甘肽作为封端剂来调节硫化镉的粒径。生物合成产生的硫化镉在紫外光下可降解90%的亚甲基蓝。此外，通过向硫化镉生物合成系统中添加锌合成了硫化镉-硫化锌纳米复合材料，这减小了硫化镉颗粒的尺寸并提高了亚甲基蓝的降解率。结果表明，嗜热四膜虫的TtCsa1生物合成的硫化镉在光催化降解有机染料方面是有效的。
