Prokaryotic Communities in Hydrothermal Vents: Insights into the Origin of Life and Potential Biomedical Applications

November 24, 2025

Hydrothermal vents provide unique environments to study microbial diversity, ecological adaptations, and their broader significance for astrobiology and biotechnology. This thesis examined prokaryotic communities from two Azorean systems: the terrestrial fumarole Caldeira Seca (CS) and shallow-water vents at São Miguel (SM). DNA was extracted from sediments, concentrated and analysed through 16S rRNA gene amplicon sequencing, followed by diverse bioinformatics tools employed in data processing and downstream statistics. CS samples yielded very low DNA concentrations, resulting in poor amplification and highly variable abundance profiles. In contrast, SM samples produced more reliable yields and reproducible results, with greater richness and evenness across replicates. Differential-abundance analyses revealed clear site-specific enrichments, with several taxa showing higher abundance in SM, including Acidithrix ferrooxidans and Actinomarinicola tropica, and others in CS, notably Alicyclobacillus disulfidooxidans. In silico analyses of Acidithrix and Rhodothermus genomes revealed functional signatures through Protein Family (Pfam) and Clusters of Orthologous Groups of Proteins (COGs) annotations, alongside Biosynthethic Gene Clusters (BGCs) for terpenoids, carotenoids, squalene, phytoene, betalactones, ranthipeptides, nucleoside derivatives and redox cofactors, several with recognised pharmaceutical and industrial value and adaptive characteristics to dynamic environments, with potential applications as Europa and Enceladus life analogues. These results position Azorean hydrothermal vents as natural laboratories for investigating microbial diversity, functional potential and analogues of life in extraterrestrial settings, in particular in icy moons with a subsurface ocean.

Authors in the community:

• 

  M

  Margarida da Costa Cordeiro

  ist199691

Supervisors of this institution:

• 

  Z

  Zita Martins

  ist31684

• 

  R

  Rodrigo da Silva Costa

  ist426960

industrial-biotechnology - Industrial Biotechnology

eng - English

Instituto Superior Técnico