New paper in Applied and Environmental Microbiology: “A Model Addressing Enzyme Strategies in Free-Living bacterioplankton”

Monday 21 Sep 15


Colin Stedmon
Associate Professor
DTU Aqua
+45 35 88 34 10


Uffe Høgsbro Thygesen
Associate Professor
DTU Compute
+45 45 25 30 60
Vast amounts of carbon are stored in the ocean interior as dissolved organic matter. Bacteria and their extracellular enzymes are key for understanding the persistence and biological degradation of dissolved organic matter.

Extracellular enzymes are a first step in microbial degradation of organic compounds exceeding 600 Dalton in molecular weight. Sachia J Traving, Uffe H Thygesen, Lasse Riemann and Colin A Stedmon investigated the apparent refractory nature of dissolved organic matter in the oceans in terms of bacterial enzyme strategies (free versus cell bound). The authors’ model reveals that surface-attached and free enzymes generate unique enzyme and substrate fields and each strategy has distinctive advantages. For solitary cells the surface-attached enzymes are the most beneficial strategy. They also show that in the deep ocean, specific dissolved organic compounds likely persist below a threshold concentration and, therefore, can be perceived as resistant to degradation and utilization by free-living bacteria.


The accepted manuscript can be found here
19 JULY 2019