Hydrolytic enzyme activities were determined using L-leucine-4-methylcoumarinyl-7-amide (MCA) hydrochloride, 4-methylumbelliferyl \u03b1-D-glucopyranoside, and 4-methylumbelliferone (MUF) \u03b2-D-glucopyranoside (Sigma-Aldrich) as substrate proxies for leucine-aminopeptidase, \u03b1-glucosidase, and \u03b2-glucosidase activities, respectively. For each bottle and substrate proxy, 196 \u00b5L of unfiltered experimental or control water was added in duplicate to a pure-grade black 96-well plate (Brand Life Sciences) containing a single substrate proxy at saturation levels (final concentration 200 \u00b5M). Fluorescence (excitation 370 nm, emission 440 nm) was measured in a Tecan Infinite 200 Pro microplate reader immediately following the addition of the substrate and several more times over 7-20 h. The well plates were incubated in the dark at in situ temperature. MUF and MCA standard solutions prepared in seawater were used to determine hydrolysis rates. Killed controls (boiled sample water) and ultrapure water samples showed little change over the incubations.
This dataset is from a laboratory experiment. Four phytoplankton cultures and their associated bacterial communities were incubated in replicate roller bottles (1.9 L) over 3-6 weeks under laboratory conditions. Bacterial dynamics in the culture bottles were measured and correlated with geochemical parameters to determine the role of bacterial activities on the formation of CDOM in the cultures (Kinsey et al., 2018, see below).
\nThe data include fluorescence and\u00a0bacterial enzyme activity during CDOM Coscinodiscus monoculture experiments.\u00a0Growth stages were initial and exponential.
BCO-DMO Processing Notes:
\n- added conventional header with dataset name, PI name, version date
\n- modified parameter names to conform with BCO-DMO naming conventions
\n- converted Excel file tables to a flat file and combined\u00a0a-glu, b-glu,\u00a0and leu substrate treatments.