Untargeted proteomics from a 5,000 km+ transect across the central Pacific Ocean from Hawaii to Tahiti. The expedition crossed multiple biogeochemical provinces, inlcuding the oligotrophic North Pacific Subtropical Gyre, the extremety of the Eastern Tropical North Pacific Oxygen Deficient Zone, and the relatively productive equatorial region associated with upwelling. This dataset focuses on the microbial fraction (0.2-3.0 micrometer filter size) and the microbial community dynamics across these biogeochemical provinces, from the surface oceance to the mesopelagic (1,250 m depth maximum).