Advanced aspects of acetogens
Anja Poehlein, Benjamin Zeldes, Maximilian Flaiz, Tim Böer, Alina Lüschen, Franziska Höfele, Kira S Baur, Bastian Molitor, Christian Kröly, Meng Wang, Quan Zhang, Yixuan Fan, Wei Chao, Rolf Daniel, Fuli Li, Mirko Basen, Volker Müller, Largus T. Angenent, Diana Z. Sousa, Frank R. Bengelsdorf
Abstract
• Presentation of the current taxonomy of known acetogens. • Appearance of recently isolated and described acetogens. • Discussion of the physiology and diversity of redox carriers in acetogens. • Summary of metabolic engineering efforts using specific acetogens. • Features of mixed and co-cultures as well as bioreactor technologies. Acetogens are a diverse group of anaerobic bacteria that are capable of carbon dioxide fixation and have for long fascinated scientists due to their unique metabolic prowess. Historically, acetogens have been recognized for their remarkable ability to grow and to produce acetate from different one-carbon sources, including carbon dioxide, carbon monoxide, formate, methanol, and methylated organic compounds. The key metabolic pathway in acetogens responsible for converting these one-carbon sources is ́the Wood-Ljungdahl pathway. This review offers a comprehensive overview of the latest discoveries that are related to acetogens. It delves into a variety of topics, including newly isolated acetogens, their taxonomy and physiology and highlights novel metabolic properties. Additionally, it explores metabolic engineering strategies that are designed to expand the product range of acetogens or to understand specific traits of their metabolism. Lastly, the review presents innovative gas fermentation techniques within the context of industrial applications.