ROLE OF TRACE ELEMENTS (ZINC, MANGANESE AND COPPER) IN THE REGULATION OF HUMAN MICROBIOTA

Abstract

ABSTRACT: The availability of vital trace elements has a significant impact on the composition and function of the human microbiota, a dynamic and tightly controlled ecosystem. As cofactors for enzymes involved in DNA synthesis, energy production, and oxidative stress defense, zinc (Zn), manganese (Mn), and copper (Cu) are essential micronutrients for microbial metabolism. However, when these metals are present in excess, they are inherently poisonous, thus both the host and the microbes must exercise rigorous regulatory control. Through homeostatic and immune-mediated processes, the host actively modifies trace element availability to limit pathogen virulence and microbial growth. This process is known as nutritional immunity. As a result, pathogenic and commensal bacteria have developed complex methods for acquiring, storing, and detoxifying metals that allow them to survive in environments that are either metal-rich or metal-restricted. Zn, Mn, and Cu homeostasis disruptions—caused by dietary imbalance, inflammation, or illness—can dramatically change microbial community structure, metabolic activity, and ecological stability, leading to dysbiosis and increased susceptibility to disease, according to growing experimental and clinical evidence. With a focus on mechanistic insights into metal-dependent microbial physiology, host-microbe competition, and their significance to health and illness, this narrative review incorporates current understanding on the roles of zinc, manganese, and copper in controlling the human microbiota. Future approaches to targeted microbiome modification and therapeutic intervention may benefit from a better knowledge of trace element–microbiota interactions.