Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023
Höfundar / Authors: Silja H. Hlynsdóttir, Sean M. Scully
Starfsvettvangur / Affiliations: University of Akureyri, Faculty of Natural Resource Sciences
Kynnir / Presenter: Silja H. Hlynsdóttir
The sustainable production of useful chemical building blocks, such as alcohols, remains one of the challenges of the 21st century, as processes still heavily rely on petroleum-based crude materials. The microbial production of these compounds from renewable resources offers an environmentally friendlier alternative. The study herein reports the ability of mesophilic, facultative anaerobes isolated from a geothermally-heated intertidal pool north of Húsavík, Iceland to produce 1,2-propanediol (1,2-PD) from methylpentoses. Majority of investigated strains belonged to genera Enterobacter, Shigella, and Escherichia. All 21 environmental isolates produced 1,2-PD from D-glucose, L-rhamnose, and L-fucose. During a preliminary study of the strains‘ abilities to synthesize 1,2-PD from these three model substrates, Enterobacter cloacae strains C1B, BB5C, Z1B, and BB1B and Escherichia fergusonii strain NT5CB yielded 1,2-PD titers of 90% and higher that of theoretical. Assessment of the influence of initial concentration of L-rhamnose generally showed inhibition at loadings higher than 20 mM. Strictly anaerobic conditions were not required for the production of 1,2-PD as many strains showed highest titers when cultivated under aerobic conditions. Unsurprisingly, lowest 1,2-PD yields were obtained at fully aerobic condition with the exception of Shigella sonnei (DSM 5570) that required the presence of oxygen for the successful synthesis of 1,2-PD.