The research group of Environmental Biotechnology at the Geo- and Environmental Center (GUZ) at the University of Tübingen is looking for an excellent Ph.D. candidate to support our international, interdisciplinary, and dynamic team of environmental/biological engineers, electrochemists, microbiologists, biotechnologists, and molecular biologists. The research in the Environmental Biotechnology Group is focused on investigating open, mixed, and pure microbial cultures in engineered systems-the group pioneers sustainable biotechnological production platforms, designed for future industrial adoption. In addition, the group studies the storage of renewable electric power with biological power-to-X technology. We apply methods from bioreactor design and operation (lab- and pilot-scale), genetic engineering, electrochemistry, and systems biology to next-generation sequencing and proteomics. The candidate should have the ambition to learn about analytical instruments (GC, HPLC) and have a deep curiosity about the ecology and syntrophy of natural metabolic pathways! The ideal applicant would have a background and understanding of bioreactor operation (i.e., from a masters program). Requirements include working independently and in a team, excellent management and communication skills, and high motivation. Very good computer and language skills (English) are necessary. The candidates will have the opportunity to present his/her results in international journals and conferences. English is the language of choice that is used in our international group. The candidate should have the ambition to learn about analytical instruments (GC, HPLC) and have a deep curiosity about the ecology and syntrophy of natural metabolic pathways! The ideal applicant would have a background and understanding of bioreactor operation (i.e., from a masters program). Requirements include working independently and in a team, excellent management and communication skills, and high motivation. Very good computer and language skills (English) are necessary. The candidates will have the opportunity to present his/her results in international journals and conferences. English is the language of choice that is used in our international group. The starting date can be from February 1, 2026 but can also be negotiated. The employment will be arranged by the administration of the University of Tübingen (salary TVL E13, 70%, including health insurance, 3 years). Disabled persons will be preferred in case of equal qualification.