Native metabolomics identifies pteridines as CutA ligands and modulators of copper binding
Abstract
CutA, a conserved protein across all domains of life, has been suggested to be involved in copper tolerance in bacteria, though recent studies have questioned this association, leaving its biological role unknown. To clarify its function, we studied cutA knockout mutants from two phylogenetically distant species, Synechococcus elongatus PCC 7942 and Escherichia coli , using phenotyping combined with metabolomics. To investigate the interaction of CutA with potential substrates and cofactors, we performed a series of native metabolomics experiments with CutA and cell extracts from which we identified the lumazine 2’-deoxyxanthopterin B2, a previously uncharacterized pteridine, to bind CutA in both species. Based on these results, we identified a set of other pteridines, including the essential cofactor tetrahydrobiopterin, as ligands of CutA. In the presence of pterins, we observed an increased affinity of CutA for copper ions. In addition, E. coli CutA mutants exhibited decreased copper resistance. These findings, alongside the known role of pteridines as redox shuttles, suggest a previously unrecognized role for CutA in coordinating cellular copper homeostasis and redox balance via pteridine metabolism.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (17)
Berenike C. Wagner
Department of Organismic Interactions, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Karoline Steuer-Lodd
Department of Biochemistry, University of California
Christian Geibel
Cluster of Excellence “Controlling Microbes to Fight Infections” (Excellence Cluster 2124), Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Amelie Stadelmann
Cluster of Excellence “Controlling Microbes to Fight Infections” (Excellence Cluster 2124), Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Johanna Rapp
Cluster of Excellence “Controlling Microbes to Fight Infections” (Excellence Cluster 2124), Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Hannes Link
Cluster of Excellence “Controlling Microbes to Fight Infections” (Excellence Cluster 2124), Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Tilman Schramm
Department of Biochemistry, University of California
Nouneh Boodaghian
Department of Microbiology and Plant Pathology, University of California
Ansel Hsiao
Department of Microbiology and Plant Pathology, University of California
Eva Nussbaum
Department of Organismic Interactions, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Heinz-Paul Grenzendorfer
Department of Organismic Interactions, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Reinhard Albrecht
Department of Protein Evolution, Max Planck Institute for Developmental Biology
Marcus D. Hartmann
Department of Protein Evolution, Max Planck Institute for Developmental Biology
Karl Forchhammer
Department of Organismic Interactions, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Khaled A. Selim
Microbial Biochemistry Group, Institute of Phototrophic Microbiology, Faculty of Mathematics and Natural Sciences, Heinrich-Heine University Düsseldorf
Chambers C. Hughes
Cluster of Excellence “Controlling Microbes to Fight Infections” (Excellence Cluster 2124), Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen
Daniel Petras
Cluster of Excellence “Controlling Microbes to Fight Infections” (Excellence Cluster 2124), Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen