MftG is crucial for ethanol metabolism of mycobacteria by linking mycofactocin oxidation to respiration
Ana Patrícia Graça,
Vadim Nikitushkin,
Mark Ellerhorst,
Cláudia Vilhena,
Tilman E Klassert,
Andreas Starick,
Malte Siemers,
Walid K Al-Jammal,
Ivan Vilotijevic,
Hortense Slevogt,
Kai Papenfort,
Gerald Lackner
Affiliations
Ana Patrícia Graça
Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute, Junior Research Group Synthetic Microbiology, Jena, Germany
Vadim Nikitushkin
Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute, Junior Research Group Synthetic Microbiology, Jena, Germany; University of Bayreuth, Chair of Biochemistry of Microorganisms, Kulmbach, Germany
Mark Ellerhorst
Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute, Junior Research Group Synthetic Microbiology, Jena, Germany; University of Bayreuth, Chair of Biochemistry of Microorganisms, Kulmbach, Germany
Cláudia Vilhena
Leibniz Institute for Natural Product Research and Infection Biology– Hans Knöll Institute, Department of Infection Biology, Jena, Germany
Tilman E Klassert
Respiratory Infection Dynamics, Helmholtz Centre for Infection Research - HZI Braunschweig, Braunschweig, Germany; Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, German Center for Lung Research (DZL), BREATH, Hannover, Germany
Andreas Starick
Friedrich Schiller University Jena, Institute of Microbiology, Jena, Germany; Microverse Cluster, Friedrich Schiller University Jena, Jena, Germany
Malte Siemers
Friedrich Schiller University Jena, Institute of Microbiology, Jena, Germany; Microverse Cluster, Friedrich Schiller University Jena, Jena, Germany
Walid K Al-Jammal
Friedrich Schiller University Jena, Institute of Organic Chemistry and Macromolecular Chemistry, Jena, Germany
Ivan Vilotijevic
Friedrich Schiller University Jena, Institute of Organic Chemistry and Macromolecular Chemistry, Jena, Germany
Hortense Slevogt
Respiratory Infection Dynamics, Helmholtz Centre for Infection Research - HZI Braunschweig, Braunschweig, Germany; Department of Respiratory Medicine and Infectious Diseases, Hannover Medical School, German Center for Lung Research (DZL), BREATH, Hannover, Germany
Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute, Junior Research Group Synthetic Microbiology, Jena, Germany; University of Bayreuth, Chair of Biochemistry of Microorganisms, Kulmbach, Germany; Microverse Cluster, Friedrich Schiller University Jena, Jena, Germany
Mycofactocin is a redox cofactor essential for the alcohol metabolism of mycobacteria. While the biosynthesis of mycofactocin is well established, the gene mftG, which encodes an oxidoreductase of the glucose-methanol-choline superfamily, remained functionally uncharacterized. Here, we show that MftG enzymes are almost exclusively found in genomes containing mycofactocin biosynthetic genes and are present in 75% of organisms harboring these genes. Gene deletion experiments in Mycolicibacterium smegmatis demonstrated a growth defect of the ∆mftG mutant on ethanol as a carbon source, accompanied by an arrest of cell division reminiscent of mild starvation. Investigation of carbon and cofactor metabolism implied a defect in mycofactocin reoxidation. Cell-free enzyme assays and respirometry using isolated cell membranes indicated that MftG acts as a mycofactocin dehydrogenase shuttling electrons toward the respiratory chain. Transcriptomics studies also indicated remodeling of redox metabolism to compensate for a shortage of redox equivalents. In conclusion, this work closes an important knowledge gap concerning the mycofactocin system and adds a new pathway to the intricate web of redox reactions governing the metabolism of mycobacteria.
