Research Group Pathology and Biogenic Stress Biology of Marine Macrophytes


Communication through molecular signals is a fundamental principle that structures the association of marine organisms. Cues regulate the behavior and thereby deter- mine the ecological functions of bacteria, protists, seaweeds and animals alike.

This gets particularly obvious when we look at sessile organisms: Their sedentary lifestyle forces them to develop efficient strategies that warrant protection from consumers, epibionts, competitors and pathogens and that attract symbiotic organisms and the gametes of mating partners. In order to reach such goals a wealth of various deterrents, attractants and molecular cues is employed. Moreover, many of the numerous microorganisms present in sea water may settle on the surfaces of marine organisms, forming biofilms and modulating the exchange of metabolites and chemical signals between their host and the environment.

The production and release of signaling compounds by marine organisms is regulated by various environmental triggers. Many of these triggers are again molecular signals, generated by synergistic or antagonistic organisms. Others are abiotic factors, such as light or water temperature. These may be perceived through specific sensing mechanisms (example: light receptors), but they may also cause shifts in the interaction networks among organisms if they change the availability of resources (example: light limitation of photosynthesis) or if they cause stressful physiological conditions (example: damage by excess light).

Our goal is to identify ecologically important chemical signals, to unravel the molecular mechanisms that regulate behavior and to understand the potential impact of environmental change upon the chemical interactions of marine organisms.

We are a member of the scientific cluster of excellence "Future Ocean" and of the academic network "Phycomorph".

Florian Weinberger: Group leader
Nadja Stärck: Technician
Sophie Steinhagen: PhD student
Guido Bonthond: PhD student
Helena Hager: MSc student
Okiemute Onoyiwe: MSc student

Recent projects

(1) Identification of compounds that deter pathogens,
     epibionts and consumers
     (a) in Gracilaria vermiculophylla, an invasive red alga
          originating from East Asia,
     (b) in eelgrass (Zostera marina) and bladderwrack
           (Fucus vesiculosus), two important habitat forming
           macrophytes in the Baltic Sea.

(2) Innate immunity and regulation of defenses in the same
     three model organisms.

(3) Invasion ecology of seaweeds:
      • Plasticity of stress resistance traits in native and non-native populations,
      • Interactions among native and non-native species.

(4) Biology of bloom-forming and drifting seaweeds; green tides.
     Morphological plasticity of Ulva-species in the North Sea and the Baltic Sea and its causes:
     Environmental conditions, genetic disposition or associated microorganisms?

(5) Perception of beach wrack by beach users: How important are odorant compounds,
     appearance and tactile stimuli for the overall perception?

For a description of our group see also here!