Article
Multidisciplinary Sciences
Nico Nouwen, Clemence Chaintreuil, Joel Fardoux, Eric Giraud
Summary: The mutant of Bradyrhizobium ORS285 lacking GOGAT activity has a significant impact on nitrogen source utilization and nitrogen fixation, especially in the symbiotic interaction with NF-independent Aeschynomene species. The mutant induces plant defense responses and is capable of nodule induction in NF-dependent species, but with ineffective nitrogen fixation. Overall, the study highlights the importance of GOGAT in nitrogen-fixing symbiosis.
SCIENTIFIC REPORTS
(2021)
Article
Biotechnology & Applied Microbiology
Li Sun, Zhenpeng Zhang, Xiaoyan Dong, Zhihong Tang, Bao Ju, Zongjun Du, Entao Wang, Zhihong Xie
Summary: In this study, three Bradyrhizobium strains were isolated from root nodules of Aeschynomene indica in Shandong Peninsula and identified as a new species named Bradyrhizobium aeschynomenes sp. nov.
SYSTEMATIC AND APPLIED MICROBIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Shingo Hata, Serina Kojima, Risa Tsuda, Nanami Kawajiri, Hiroshi Kouchi, Takamasa Suzuki, Kazuma Uesaka, Aiko Tanaka
Summary: We isolated a novel strain of Bradyrhizobium sp., SSBR45, from the nodulated roots of Aeschynomene indica and determined its draft genomic sequence. The labeled SSBR45 significantly promoted the growth of A. indica on a nitrogen-free medium, as observed by visualizing the fluorescent root nodules. SSBR45, a novel species of the genus Bradyrhizobium, possessed genes involved in nitrogen fixation, photosynthesis, and type IV secretion system, but lacked canonical nodABC genes and type III secretion system genes. It showed an average nucleotide identity and average amino acid identity of 87% and 90%, respectively, with the closest strain B. oligotrophicum S58.
PLANT SIGNALING & BEHAVIOR
(2023)
Article
Biochemistry & Molecular Biology
Nicolas Busset, Djamel Gully, Albin Teulet, Joel Fardoux, Alicia Camuel, David Cornu, Dany Severac, Eric Giraud, Peter Mergaert
Summary: The study expanded the catalog of T3SS effectors of Bradyrhizobium vignae ORS3257 using a multi-omics approach, showing that most of the putative effectors are regulated by TtsI and confirming the secretion of some T3Es through proteome analysis. Additionally, the research identified and validated a new potential T3Es.
Article
Ecology
Ryan S. Nett, Kelly S. Bender, Reuben J. Peters
Summary: Gibberellin produced by rhizobia can influence the size and number of nodules in soybean, benefiting both the bacteria and the plant.
Article
Microbiology
Dipanwita Patra, Sukhendu Mandal
Summary: This review focuses on different types of Bradyrhizobium species, types of nodule formation, nodulation regulation, comparative mechanism of nod-dependent and independent nitrogen fixation in legume plants, relationship with type 3 secretion systems (T3SS) and NI nitrogen fixation by Bradyrhizobium, the role of NF receptor homolog and NF in symbiosis. It predicts the transition of one group of symbionts to another unique type, where pathogen-associated machinery like T3SS plays a role in symbiosis.
Article
Plant Sciences
Antoine Vergne, Vincent Darbot, Corinne Bardot, Francois Enault, Anne-Helene Le Jeune, Jean-Francois Carrias, Bruno Corbara, Regis Cereghino, Celine Leroy, Christian Jeanthon, Eric Giraud, Isabelle Mary, Anne-Catherine Lehours
Summary: The study found that APB communities were specific to plant species and less dependent on location or habitat characteristics. The dominant factor explaining variance in APB community composition was the species of bromeliad, suggesting a close, mutualistic relationship between APB and tank bromeliads. The presence of nitrogen-fixing genes in APB communities inhabiting tank bromeliads may benefit the nutritional needs of bromeliads.
JOURNAL OF ECOLOGY
(2021)
Review
Biochemical Research Methods
Benjamin Gourion, Pascal Ratet
Summary: Microbes interacting with plants can provide benefits such as protection against stresses and improved nutrition, but plants must also defend against parasites and pathogens. Evolution has led to improved tolerance and defense responses in plants to manage interactions with beneficial and detrimental microbes.
CURRENT OPINION IN BIOTECHNOLOGY
(2021)
Correction
Multidisciplinary Sciences
Pongpan Songwattana, Clemence Chaintreuil, Jenjira Wongdee, Albin Teulet, Mamadou Mbaye, Pongdet Piromyou, Djamel Gully, Joel Fardoux, Alexandre Mahougnon Aurel Zoumman, Alicia Camuel, Panlada Tittabutr, Neung Teaumroong, Eric Giraud
Summary: An amendment to this paper has been published and is accessible through a link at the top of the paper.
SCIENTIFIC REPORTS
(2021)
Article
Ecology
L. Tighilt, F. Boulila, B. F. S. De Sousa, E. Giraud, T. Ruiz-Argueso, J. M. Palacios, J. Imperial, L. Rey
Summary: The type VI secretion system (T6SS) in the symbiotic strain of the genus Bradyrhizobium plays an important role in nodule formation with legumes, affecting plant growth and competitiveness. The T6SS genes in Bradyrhizobium A16 are organized in two clusters, including a gene encoding a protein of unknown function. This study reveals the function of T6SS and its impact on nodulation.
Review
Microbiology
Albin Teulet, Alicia Camuel, Xavier Perret, Eric Giraud
Summary: The type III secretion systems (T3SSs) used by rhizobia deliver effector proteins (T3Es) inside host cells to suppress plant immunity and promote infection for nitrogen fixation. The immune system of legume hosts and the cocktail of T3Es secreted by rhizobia determine the outcome of their symbiotic interaction. Rhizobial T3Es can either reduce plant immunity and promote infection or trigger defense responses if recognized by plant receptors. Some rhizobial T3Es can also bypass nodulation factors to induce nodule formation.
ANNUAL REVIEW OF MICROBIOLOGY
(2022)
Article
Agronomy
Dyah Wulandari, Pongpan Songwattana, Frederic Gressent, Pongdet Piromyou, Kamonluck Teamtisong, Nantakorn Boonkerd, Eric Giraud, Panlada Tittabutr, Neung Teaumroong
Summary: This study found that Bradyrhizobium sp. DOA9 has a broad host range and highly divergent nodulation genes. The duplicated copies of the nodD and nodA genes may affect symbiotic nodulation through functional redundancy. Furthermore, nodA2 and nodB genes play a central role in Nod-Factor biosynthesis and symbiotic nodulation.
Article
Plant Sciences
Laurent Sauviac, Antoine Remy, Emeline Huault, Melanie Dalmasso, Theophile Kazmierczak, Marie-Francoise Jardinaud, Ludovic Legrand, Corentin Moreau, Bryan Ruiz, Anne-Claire Cazale, Sophie Valiere, Benjamin Gourion, Laurence Dupont, Veronique Gruber, Eric Boncompagni, Eliane Meilhoc, Pierre Frendo, Florian Frugier, Claude Bruand
Summary: This study identified hundreds of plant and bacterial genes associated with nodule senescence through dual plant-bacteria RNA sequencing, providing a valuable resource for exploring the mechanisms of nodule senescence. The study revealed that genes related to both plant and bacterial cell cycle and stress responses play important roles in nodule senescence, suggesting complex regulatory networks involved in this process.
PLANT CELL AND ENVIRONMENT
(2022)
Article
Plant Sciences
Marie-Francoise Jardinaud, Sebastien Carrere, Benjamin Gourion, Pascal Gamas
Summary: Symbiotic nitrogen fixation plays a key role in reducing the negative impact of nitrogen fertilizers in agroecosystems. The efficiency of this process is influenced by the combination of bacterial and plant genotypes, but the mechanisms behind differences in the efficiency of rhizobium strains are not well known.
PLANT AND CELL PHYSIOLOGY
(2023)
Editorial Material
Plant Sciences
Maria J. Soto, Christian Staehelin, Benjamin Gourion, Luis Cardenas, Jose M. Vinardell
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Plant Sciences
Fathi Berrabah, Gautier Bernal, Ait-Salem Elhosseyn, Cyrille El Kassis, Roxane L'Horset, Farouk Benaceur, Jiangqi Wen, Kirankumar S. Mysore, Marie Garmier, Benjamin Gourion, Pascal Ratet, Veronique Gruber
Summary: This study investigated the relationship between senescence and immunity in Medicago nodules. It found that in nonfunctional nodules, senescence and immunity appear to be antagonistic, while in normal nodules under stress, they switch to a synergistic relationship. The study also identified key genes involved in symbiotic immunity suppression. Understanding the links between senescence and immunity in nodules contributes to the knowledge of nodule organogenesis.
Editorial Material
Ecology
Antoine Vergne, Eric Giraud, Alicia Camuel, Corinne Bardot, Hermine Billard, Clementin Bouquet, Bruno Corbara, Djamel Gully, Frederic Mathonat, Christian Jeanthon, Isabelle Mary, Jean-Claude Caissard, Anne-Catherine Lehours
Article
Microbiology
Jenjira Wongdee, Pongdet Piromyou, Pongpan Songwattana, Teerana Greetatorn, Neung Teaumroong, Nantakorn Boonkerd, Eric Giraud, Nico Nouwen, Panlada Tittabutr
Summary: RpoN is an alternative sigma factor that recruits the core RNA polymerase to gene promoters. It has diverse physiological functions in bacteria, including a key role in nitrogen fixation genes. In the Bradyrhizobium sp. DOA9 strain, both the chromosomal and plasmid encoded RpoN proteins have pleiotropic effects on the physiology of the bacteria under free-living and symbiotic conditions. Inactivation of these proteins severely impacts bacterial motility, carbon and nitrogen utilization, EPS production, and biofilm formation under free-living conditions, and also reduces symbiotic nodulation, nitrogen fixation efficiency, and intracellular survival ability.
FRONTIERS IN MICROBIOLOGY
(2023)
Review
Biotechnology & Applied Microbiology
Erhard Bremer, Alexandra Calteau, Antoine Danchin, Colin Harwood, John D. Helmann, Claudine Medigue, Bernhard O. Palsson, Agnieszka Sekowska, David Vallenet, Abril Zuniga, Cristal Zuniga
Summary: The majority of genomic sequences are automatically annotated, but depend on manual annotation efforts using verified experimental data. This article summarizes the updated functional annotation of Bacillus subtilis strain 168, highlighting new metabolic insights, the role of metals in metabolism and biosynthesis, functions related to biofilm formation, features controlling cell growth, and protein agents allowing class discrimination. The updated sequence, including new genomic objects and literature review, is available at the International Nucleotide Sequence Database Collaboration (INSDC: AccNum AL009126.4).
MICROBIAL BIOTECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Flaviana Di Lorenzo, Simone Nicolardi, Roberta Marchetti, Adele Vanacore, Noemi Gallucci, Katarzyna Duda, Ferran Nieto Fabregat, Ha Ngoc Anh Nguyen, Djamel Gully, James Saenz, Eric Giraud, Luigi Paduano, Antonio Molinaro, Gerardino D'Errico, Alba Silipo
Summary: The ability of Methylobacterium extorquens to grow on methanol as the sole carbon and energy source is influenced by the composition and function of the lipopolysaccharide (LPS) in the outer membrane. The LPS of M. extorquens is unique, with non-phosphorylated and heavily O-methylated core oligosaccharides, and a distinctive lipid A structure. These chemical features impact the resistance of the membrane to methanol, regulating membrane ordering and dynamics.
Article
Plant Sciences
Johan Quilbe, Nico Nouwen, Marjorie Pervent, Remi Guyonnet, Julie Cullimore, Frederic Gressent, Natasha Horta Araujo, Djamel Gully, Christophe Klopp, Eric Giraud, Jean-Francois Arrighi
Summary: Characterization of Aeschynomene evenia mutants altered in nodulation provides insights into the mechanisms of Nod-independent symbiosis and contributes to the understanding of rhizobium-legume symbiosis.
