Jürgen Wierz

Jürgen Wierz

Evolutionäre Ökologie

Institut für Organismische und Molekulare Evolutionsbiologie
Hanns-Dieter-Hüsch-Weg 15
55128 Mainz

phone: +49 - (0) 6131 - 39 26717
fax: +49 - (0) 6131 - 39 23731



Research      -     CV

Research Interest

Microbial symbionts are ubiquitous in this world, supporting their hosts in various different ways and sometimes even enter obligatory relationships with the host. Due to their enormous variety of biochemical pathways, bacteria are particularly valuable symbiotic partners.

Beetles (Coleoptera) are the largest of all insect orders. Their most outstanding characteristic is that their front pair of wings are hardened into protective wing-cases, called elytra. This guarantees them extra protection against predators, pathogens and provides a higher desiccation resistance. However, this comes with a cost as it makes them require a very high amount of tyrosine during development, because it is crucial for cuticle biosynthesis, hardening, and tanning. Insects in general are not able to produce tyrosine on their own and rely on either taking up the amino acid through food or with the help of symbionts. In beetles multiple different families are associated with microbial symbionts that provision their host with tyrosine.

I focus on the beetle families of Melyridae, Throscidae and Zopheridae. Here, I want to find out what the taxonomic distribution of tyrosine supplementing symbionts is in order to get new insights about the evolutionary history of the symbionts. Furthermore, whole representative symbiont genomes will be sequenced to compare the metabolic capabilities of the symbionts within and across those families. In addition to this I analyze how the hosts regulate their symbiont titers and/or the tyrosine metabolism as symbionts are costly besides all their benefits and need to be regulated by the host. An interesting question I try to answer via GCMS analysis is what the actual chemical contribution to the cuticle in terms of AS provision by the symbionts is and how impactful it is. This will shed light on how strong the differences between symbiotic and aposymbiotic beetles are and in which life stages those differences occur.



  • 2015 - 2016 | BSC. IN BIOLOGY | JGU MAINZ
    • Thesis: “Ant personality and roles during the recruitment process of Temnothorax ants”


  • 2016 - 2018 | MSC. IN BIOLOGY | JGU MAINZ
    • Thesis: “Transmission and pathogenicity of Burkholderia gladioli symbionts of Lagria beetles in crop plants”


  • Seit 2019
    • Doktorand, Evolutionäre Ökologie, iOME | JGU MAINZ


Wierz, J.C., Gaube, P., Klebsch, D., Kaltenpoth M. & Flórez, L.V. (2021) Transmission of Bacterial Symbionts With and Without Genome Erosion Between a Beetle Host and the Plant Environment, doi: 10.3389/fmicb.2021.715601

Kiefer, J. S. T. et al. (2021) Inhibition of a nutritional endosymbiont by glyphosate abolishes mutualistic benefit on cuticle synthesis in Oryzaephilus surinamensis, Communications Biology 4: 554, DOI: 10.1038/s42003-021-02057-6