Farias Pedro, Francisco Romeu, Maccario Lorrie, Herschend Jakob, Sørensen Søren J, Morais Paula V
University of Coimbra, CEMMPRE, ARISE, Department of Life Sciences, 3000-456, Coimbra, Portugal.
Department of Biology, Section of Microbiology, University of Copenhagen, Copenhagen, Denmark.
Sci Rep. 2025 Apr 13;15(1):12745. doi: 10.1038/s41598-025-95321-2.
Contaminated environments can pose new challenges when new contaminants appear and can select organisms with new genetic and metabolic strategies. The increased presence of Te(IV) in the environment is becoming more important. This highlights how underexplored the investigation of how bacteria molecularly respond to less common environmental contaminants, such as tellurite when compared to other metals/ metalloids. Understanding what tools an organism uses from its genetic pool when responding to a new contaminant requires a multiple-technique approach, such as metabolic tests and differential omics analysis. These analyses provide a full metabolic and phenotypical map of stress response that can include new resistance mechanisms, whether specific or not. This study aimed to determine if Bacillus altitudinis strain 3W19, isolated from a Te(IV) contaminated site, presents specific changes at the proteomic level when exposed to the metalloid. In strain 3W19, growth in the presence of Te(IV) upregulated pathways of amino acid metabolism and membrane transport and downregulated pathways of carbohydrate metabolism. Growth in the presence of Te(IV) also induced the formation of reactive oxygen species and lowered the metabolic activity of the strain. This metal led to the overexpression of the proteins of the ter gene cluster. When compared with other strains, the ter system identified in this strain differed in genomic organization from related Bacillus sp. strains. Together, these strain-specificities can contribute to understanding its Te(IV) resistance phenotype.
当新的污染物出现时，受污染的环境会带来新的挑战，并可能选择具有新的遗传和代谢策略的生物。环境中四价碲（Te(IV)）含量的增加正变得越来越重要。这凸显出，与其他金属/类金属相比，细菌如何在分子水平上响应不太常见的环境污染物（如亚碲酸盐）的研究仍未得到充分探索。要了解生物体在应对新污染物时从其基因库中使用了哪些工具，需要采用多种技术方法，如代谢测试和差异组学分析。这些分析提供了应激反应的完整代谢和表型图谱，其中可能包括新的抗性机制，无论其是否具有特异性。本研究旨在确定从受Te(IV)污染的地点分离出的高海拔芽孢杆菌3W19菌株在暴露于该类金属时，在蛋白质组水平上是否会出现特定变化。在3W19菌株中，在Te(IV)存在的情况下生长会上调氨基酸代谢和膜转运途径，并下调碳水化合物代谢途径。在Te(IV)存在的情况下生长还会诱导活性氧的形成，并降低该菌株的代谢活性。这种金属导致了ter基因簇蛋白的过度表达。与其他菌株相比，该菌株中鉴定出的ter系统在基因组组织上与相关芽孢杆菌属菌株不同。总之，这些菌株特异性有助于理解其对Te(IV)的抗性表型。
