Gehin Gaitan, Carraro Nicolas, van der Meer Jan Roelof, Peña Jasquelin
Department of Civil and Environmental Engineering, University of California, Davis, CA, USA.
Department of Fundamental Microbiology, University of Lausanne, Vaud, CH, Switzerland.
NPJ Biofilms Microbiomes. 2025 Mar 24;11(1):50. doi: 10.1038/s41522-025-00670-5.
The enzymatic oxidation of aqueous divalent manganese (Mn) is a widespread microbial trait that produces reactive Mn(III, IV) oxide minerals. These biominerals drive carbon, nutrient, and trace metal cycles, thus playing important environmental and ecological roles. However, the regulatory mechanisms and physiological functions of Mn biomineralization are unknown. This challenge arises from the common occurrence of multiple Mn oxidases within the same organism and the use of Mn oxides as indicators of combined gene activity. Through the detection of gene activation in individual cells, we discover that expression of mnxG and mcoA, two Mn oxidase-encoding genes in Pseudomonas putida GB-1, is confined to subsets of cells within the population, with each gene showing distinct spatiotemporal patterns that reflect local microenvironments. These coordinated intra-population dynamics control Mn biomineralization and illuminate the strategies used by microbial communities to dictate the extent, location, and timing of biogeochemical transformations.
二价锰（Mn）在水溶液中的酶促氧化是一种广泛存在的微生物特性，可产生具有反应活性的Mn（III, IV）氧化物矿物。这些生物矿物驱动着碳、养分和痕量金属循环，因此发挥着重要的环境和生态作用。然而，锰生物矿化的调控机制和生理功能尚不清楚。这一挑战源于同一生物体中多种锰氧化酶的普遍存在，以及使用锰氧化物作为联合基因活性的指标。通过检测单个细胞中的基因激活情况，我们发现恶臭假单胞菌GB-1中两个编码锰氧化酶的基因mnxG和mcoA的表达仅限于群体中的部分细胞，每个基因都呈现出独特的时空模式，反映了局部微环境。这些群体内的协同动态控制着锰生物矿化，并阐明了微生物群落用于决定生物地球化学转化的程度、位置和时间的策略。
