Onderwerp scriptie

Co-cultivating sponge associated microorganisms

Marine sponges harbor a plethora of yet unexplored bioactive components, and microbial origin is suspected for many metabolites. However, sponge associated bacteria have not been isolated yet so their potential cannot be successfully exploited. Therefore, novel cultivation strategies have to be developed and applied so the yet uncultured sponge-associated microorganisms can be studied physiologically, and their drug-producing potential can be explored and exploited.

We currently investigate the holobiont of two Mediterranean sponge species (Aplysina aerophoba and Dysidea avara) with multiple molecular approaches, including analysis of community composition, metabolic screening and functional metagenomics and metatranscriptomics, in order to design cultivation conditions based on genomic predictions and to identify promising co-culture candidates. We are working on developing novel and innovative cultivation technologies that by imitating the natural conditions in the sponge enable us to isolate yet uncultured microorganisms. Since in the sponge the microorganisms live in close relationship to each other and communicate and cross feed, we try to maintain those relationships in our cultivation experiments and aim for the cultivation and characterization of defined multi-species communities.

Techniques and Methods:

Designing innovative cultivation experiments for sponge associated bacteria

PCR, DNA extraction

Light and Fluorescence Microscopy

Oxygen, pH and redox potential measurements

Diversity (16S) and genome sequencing

Sequencing data analysis


We are looking for creative and motivated Master students that are interested in marine (micro-)biology and biotechnology. Your ideas and suggestions are most welcome, and if feasible we will try to realize them in the course of the 6 month thesis project. Don’t hesitate to contact us if you’re up for a scientific adventure!


Johanna Gutleben


0317 480062

Laboratory of Microbiology

Microbiology building, room K. 016


Dr. Detmer Sipkema


Tel: 0317-483113

Laboratory of Microbiology

Microbiology building, room 0023

Duration: 5-6.5 months

Credits: 39 (max.)