Home Page | Help | Contact | Log In | Search | Follow us: Official ASLO 2011 ASM Twitter Feed Official ASLO 2011 ASM Facebook Page

Navigation

del Valle, D. A., University of Hawaii, Honolulu, HI, USA, dadv@hawaii.edu
Kiene, R. P., University of South Alabama, Mobile, AL, USA, rkiene@disl.org
Karl, D. M., University of Hawaii, Honolulu, HI, USA, dkarl@hawaii.edu

LIGHT DEPENDENCE OF DISSOLVED DMSP-SULFUR ASSIMILATION AND DMS PRODUCTION IN THE OLIGOTROPHIC NORTH PACIFIC SUBTROPICAL GYRE

The aim of the present study was to assess the effect of photosynthetically active radiation (PAR, 400-700 nm) on the utilization of dissolved dimethylsulfoniopropionate (DMSPd) by the microbial community of the oligotrophic North Pacific subtropical gyre. Rates of DMSPd-sulfur assimilation into macromolecules in surface mixed layer seawater were 39-78% higher in light than in dark-incubated samples, and there was no photoinhibition in the light range tested (0 to 1200 µEin m-2 s-1). DMSPd-sulfur assimilation was highly correlated (r=0.93) to leucine assimilation, indicating that cells can respond quickly to sulfur requirements for protein synthesis by assimilating DMSP-sulfur. Light-driven changes in DMSPd-sulfur assimilation were inversely correlated (r=-0.57) to changes in the corresponding DMS yield (i.e., DMS produced per DMSP consumed), in agreement with the hypothesis that DMS is produced when cellular sulfur requirements are met. However, more than ≈50% of the DMSPd product pool remained unidentified, suggesting that there might be other metabolic processes or products that can potentially regulate DMS production, besides assimilation.

Session #:S86
Date: 02-18-2011
Time: 16:15

Presentation is given by student: No