LAUSR

Significance Enzymatic proteins are the engines of life, generating energy, fixing CO2 into organic matter, and building biomass. At scale, these biological catalysts have the power to drive global elemental cycles. These microbial machines were responsible for the oxygenation of the atmosphere, can mediate the formation and destruction of greenhouse gases, and potentially influence cloud formation. Here, we used metaproteomics across the central Pacific Ocean to investigate how microbial protein distributions change across vertical and horizontal scales, identify interactions among microbial consortia, and characterize metabolic hot spots in line with major geochemical features. These observations provide insights into microbial community dynamics and can act as empirical constraints for biogeochemical ecosystem models to improve understanding of microbial interactions on a changing planet.