microbiology

Enigmatic persistence of dissolved organic matter in the oceans

Marine dissolved organic matter (DOM) contains more carbon than the combined stocks of Earth’s biota. Organisms in the ocean continuously release a myriad of molecules that become food for microheterotrophs, but, for unknown reasons, a residual …

Story behind the paper: Optimal stock-enhancement of a spatially distributed renewable resource

When the watering can principle is not a good idea to manage your ecosystem

Shape matters: the relationship between cell geometry and diversity in phytoplankton

We analyse data on marine unicellular phytoplankton, exhibiting an astounding diversity of cell sizes and shapes. We quantify the variation in size and shape and explore their effects on taxonomic diversity. We find that cells of intermediate volume exhibit the greatest shape variation, with shapes ranging from oblate to extremely elongated forms, while very small and large cells are mostly compact. We show that cell shape has a strong effect on phytoplankton diversity, comparable in magnitude to the effect of cell volume, with both traits explaining up to 92% of the variance in phytoplankton diversity. Species richness decays exponentially with cell elongation and displays a log-normal dependence on cell volume, peaking for compact cells of intermediate volume.

Microbial physiology governs the oceanic distribution of dissolved organic carbon in a scenario of equal degradability

Dissolved organic carbon (DOC) forms one of the largest active organic carbon reservoirs on Earth and reaches average radiocarbon ages of several thousand years. Many previous large scale DOC models assume different lability classes (labile to …

The Gossip Paradox: why do bacteria share genes?

Bacteria, in contrast to eukaryotic cells contain two types of genes: chromosomal genes that are fixed to the cell, and plasmids that are mobile genes, easily shared to other cells. The sharing of plasmid genes between individual bacteria and between …

Marine geochemistry

Complex systems theory of dissolved organic matter

Movement Ecology

Linking magnetic and other orientation cues to global migration patterns

New Publication: Shape matters: cell geometry determines phytoplankton diversity

Exploring the shape-diversity relationship in phytoplankton

Amino Acid and Sugar Catabolism in the Marine Bacterium Phaeobacter inhibens DSM 17395 from an Energetic Viewpoint

Growth energetics and metabolic efficiency contribute to the lifestyle and habitat imprint of microorganisms. Roseobacters constitute one of the most abundant and successful marine bacterioplankton groups. Here, we reflect on the energetics and …

The marine bacterium Phaeobacter inhibens secures external ammonium by rapid buildup of intracellular nitrogen stocks

Reduced nitrogen species are key nutrients for biological productivity in the oceans. Ammonium is often present in low and growth-limiting concentrations, albeit peaks occur during collapse of algal blooms or via input from deep sea upwelling and …