[AE2413 FlaPS bulk] - Polysaccharide hydrolase activities from water samples collected at various sites under varying hydrostatic pressures in the Western North Atlantic aboard R/V Atlantic Explorer cruise AE2413 in May 2024 (Collaborative Research: Pressure effects on microbially-catalyzed organic matter degradation in the deep ocean)

We have new evidence that a substantial fraction of bacteria in bottom water from the North Atlantic Ocean use a specialized set of extracellular enzymes to rapidly take up HMW polysaccharides (Giljan et al. 2021), a substrate processing mechanism that would not be detected with the low molecular weight substrates used in most prior studies of microbial activity in the deep ocean (Nagata et al. 2010). Through our collaboration with the Danish Center for Hadal Research, we were able to use pressurization systems and in situ specialized equipment to investigate the effects of pressures characteristic of bathy- and abyssopelagic depths on microbial communities and their extracellular enzymes in the open North Atlantic Ocean.

Here we present the measurement of polysaccharide hydrolase activities above that measured for killed controls from various sites under varying hydrostatic pressures in the Western North Atlantic aboard R/V Atlantic Explorer, cruise AE2413 in May 2024.