莱茵衣藻响应重金属胁迫的分子防御机制研究进展

doi:10.13560/j.cnki.biotech.bull.1985.2025-0088

摘要/Abstract

摘要：

随着城市化和工业化的快速发展，重金属污染对水生生态系统造成不可估量的威胁，并可通过食物链富集效应严重威胁人类生命健康，已然成为全球性关注的环境问题。在此背景下，以生物修复技术为代表的绿色环境治理方案因其环境友好性和可持续发展性而备受关注。藻类作为水生生态系统中的重要初级生产者，具有高度多样性和生态适应性，并通过多种分子机制响应重金属胁迫。莱茵衣藻（Chlamydomonas reinhardtii）是一种单细胞的真核微藻，通过多层次的生理结构和调控机制维持细胞内部金属离子稳态，在金属的生物转化与生物吸附方面显示出独特能力，已成为重金属污染水体修复研究的重要模式生物。莱茵衣藻细胞金属稳态机制研究的不断深入和现代生物技术的快速发展，为深入理解莱茵衣藻应对重金属胁迫防御机制提供了理论依据，也为利用莱茵衣藻进行重金属污染水体的生物修复提供科学指导。本文将从细胞表面（如细胞壁、细胞外聚合物）至细胞内部（如金属转运蛋白、重金属结合因子、维持金属稳态相关细胞器）等多层面，综述莱茵衣藻响应重金属胁迫的关键组分与调控机制，并结合现代分子生物学技术用于改造莱茵衣藻重金属生物修复能力的研究，探讨其在水环境保护领域的应用潜力。

关键词: 莱茵衣藻, 重金属胁迫, 细胞外聚合物, 金属转运蛋白, 金属结合因子

Abstract:

With the rapid development of urbanization and industrialization, heavy metal pollution has posed an immeasurable threat to aquatic ecosystems. Through the bioaccumulation effect in food chains, it severely endangers human health and has become a globally concerning environmental issue. In this context, green environmental remediation solutions represented by bioremediation have garnered significant attention due to their eco-friendliness and sustainability. As crucial primary producers in aquatic ecosystems, microalgae demonstrate high diversity and ecological adaptability, employing various molecular mechanisms to respond to heavy metal stress. Chlamydomonas reinhardtii, a unicellular eukaryotic microalga, maintains intracellular metal ion homeostasis through multi-layered physiological structures and regulatory mechanisms. Its unique capabilities in metal biotransformation and biosorption have established it as an important model organism for studying bioremediation of heavy metal-contaminated water bodies. The deepening understanding of C. reinhardtii’s metal homeostasis mechanisms and rapid advancements in modern biotechnology have provided theoretical foundations for elucidating its defense strategies against heavy metal stress, while offering scientific guidance for its application in water remediation. This review summarizes key components and regulatory mechanisms involved in its responses to heavy metal stress, spanning from cell surface adaptations (e.g., cell walls and extracellular polymeric substances) to intracellular processes (e.g., metal transport proteins, heavy metal-binding factors, and metal-regulating organelles). Furthermore, it explores the potential applications of modern molecular biology techniques in enhancing C. reinhardtii’s bioremediation capabilities and discusses its prospects in aquatic environmental protection.

Key words: Chlamydomonas reinhardtii, heavy metal stress, extracellular polymeric substances, metal transporters, metal-binding factors

李亚, 蒋林, 徐闯, 王苏慧, 马曌, 王亮. 莱茵衣藻响应重金属胁迫的分子防御机制研究进展[J]. 生物技术通报, 2025, 41(8): 53-64.

LI Ya, JIANG Lin, XU Chuang, WANG Su-hui, MA Zhao, WANG Liang. Research Progress in Molecular Defense Mechanisms of Chlamydomonas reinhardtii in Response to Heavy Metal Stress[J]. Biotechnology Bulletin, 2025, 41(8): 53-64.

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