[Peptidase and glucosidase activities from mesocosm and bulk water incubations.] - Peptidase and glucosidase activities from mesocosm and bulk water incubations from waters taken aboard the R/V Endeavor in the Western North Atlantic during the research cruise EN683 in May and June, 2022. (Substrate structural complexity and abundance control distinct mechanisms of microbially-driven carbon cycling in the ocean)

Seawater was sampled from four depths at our initial station, and the deep chlorophyll maximum and bottom water from two subsequent stations differing in typical extent of primary productivity. We incubated mesocosms of seawater from the deep chlorophyll maximum and from bottom water from two stations differing in typical extent of primary productivity. We changed organic matter availability by adding to three mesocosms high molecular weight organic matter (dissolved and particulate) from diatoms, three mesocosms received an addition of the polysaccharide fucoidan, and three mesocosms were amended with the polysaccharide arabinogalactan.

One mesocosm from each depth and station was left unamended. These data help test this model because they provide information about the activities of exo-acting glucosidases and an exo-acting peptidase, plus endo-acting peptidases, all of which are used to hydrolyze high molecular weight organic matter. Activities of these enzymes differed by station as well as by depth