biostudies-literaturePujic PAgence Nationale de la Recherche651https://www.ebi.ac.uk/biostudies/studies/S-EPMC8951365biostudies-literatureUnknown10(3)Omics are the most promising approaches to investigate microbes for which no genetic tools exist such as the nitrogen-fixing symbiotic <i>Frankia.</i> A proteogenomic analysis of symbiotic <i>Frankia alni</i> was done by comparing those proteins more and less abundant in <i>Alnus glutinosa</i> nodules relative to N₂-fixing pure cultures with propionate as the carbon source. There were 250 proteins that were significantly overabundant in nodules at a fold change (FC) ≥ 2 threshold, and 1429 with the same characteristics in in vitro nitrogen-fixing pure culture. Nitrogenase, SuF (Fe-Su biogenesis) and hopanoid lipids synthesis determinants were the most overabundant proteins in symbiosis. Nitrogenase was found to constitute 3% of all <i>Frankia</i> proteins in nodules. Sod (superoMicroorganismsThe Proteogenome of Symbiotic <i>Frankia alni</i> in <i>Alnus glutinosa</i> Nodules.PMC8951365BugsInACell ANR-13-BSV7-0013-03Abrouk DFournier PAlloisio NArmengaud JNormand PMiotello GPujic PfalseThe Proteogenome of Symbiotic <i>Frankia alni</i> in <i>Alnus glutinosa</i> Nodules.Omics are the most promising approaches to investigate microbes for which no genetic tools exist such as the nitrogen-fixing symbiotic <i>Frankia.</i> A proteogenomic analysis of symbiotic <i>Frankia alni</i> was done by comparing those proteins more and less abundant in <i>Alnus glutinosa</i> nodules relative to N₂-fixing pure cultures with propionate as the carbon source. There were 250 proteins that were significantly overabundant in nodules at a fold change (FC) ≥ 2 threshold, and 1429 with the same characteristics in in vitro nitrogen-fixing pure culture. Nitrogenase, SuF (Fe-Su biogenesis) and hopanoid lipids synthesis determinants were the most overabundant proteins in symbiosis. Nitrogenase was found to constitute 3% of all <i>Frankia</i> proteins in nodules. Sod (supero2022-01-01T00:00:00Z2022 Mar2026-04-08T09:39:23.416Z2025-04-19T22:35:58.49ZS-EPMC89513653533622710.3390/microorganisms10030651