We investigate molecular mechanisms of rhizobium–legume interactions and the regulation of horizontal gene transfer, combining genetics, microbiology and omics approaches.
Overview
Mission
Understand how rhizobia sense environmental conditions and establish specific interactions with legumes, and how plasmid-mediated genetic transfer is regulated. We combine bacterial genetics, mutagenesis, expression analysis, transcriptomics, proteomics, metabolomics and bacterium–plant assays.
Vision
Generate original knowledge about symbiosis, bacterial adaptation and genetic dynamics, train researchers and develop knowledge with potential agricultural applications through national and international collaborations.
Research areas
Molecular basis of rhizobium–legume interactions
We investigate bacterial and plant factors underlying efficient symbiosis, particularly Medicago sativa and M. truncatula with Rhizobium and Ensifer. Comparative bacterial and nodule transcriptomics and proteomics identify determinants of bacteroid differentiation and biological nitrogen fixation in efficient and inefficient associations.
Regulation of horizontal gene transfer
We investigate conjugative plasmid transfer in rhizobia and its implications for the evolution of bacterium–plant associations. We characterise rcgR and rcgA, regulators of the Rhizobium favelukesii LPU83 plasmid pLPU83a that affect transfer through different mechanisms.
Research areas shared with other units
These research areas are developed collaboratively by the participating units.
Functional genomics of bacteria of agricultural and biotechnological interest
Sequencing and functional analysis of bacterial genomes to discover mechanisms and genes of applied interest.
We sequence, assemble and annotate genomes of bacteria isolated from agricultural soils in different regions. Through data mining and comparison with international databases we identify genes related to stress tolerance, metabolite production and plant–microorganism interaction.
The integrative approach of functional genomics and systems biology provides knowledge to design next-generation bacterial inoculants and more sustainable and efficient agricultural solutions.
Participants: Mauricio Lozano, Antonio Lagares and Gonzalo Torres Tejerizo.
Bacteria–host interaction in symbiotic and pathogenic systems
Study of the molecular and cellular interactions that determine beneficial or pathogenic colonization.
We analyze how bacteria perceive host signals, modulate their gene expression and adjust their metabolism and physiology during symbiosis or infection. We use genomic, transcriptomic and proteomic approaches to identify regulators and molecular determinants of these interactions.
The knowledge generated can guide the development of more efficient agricultural inoculants and sustainable antimicrobial strategies.
Participants: María Carla Martini, Antonio Lagares and Gonzalo Torres Tejerizo.
Team
- Gonzalo Arturo Torres TejerizoGroup director · Independent Researcher CONICET
- Abril LuchettiCONICET postdoctoral fellow
- María Delfina CabreraCONICET doctoral fellow
- Catalina D'AddonaANPCyT doctoral fellow
- Ornella FaldutiCONICET doctoral fellow · Shared doctoral association: Rhizobia–Soybean Interactions
Projects and funding
- PICT2021-I-A-00153: “Omics approaches to study determinants involved in the differentiation of nitrogen-fixing bacteria”. ANPCyT; principal investigator Gonzalo A. Torres Tejerizo; reported four-year duration, still ongoing in the presentation.
- PIET-R 2025, code 29820250100147CO, 2026–2028: regulation of stress memory or priming in soybean using beneficial microorganisms and/or priming inducers carried by biodegradable seed biopolymers. CONICET; participation in the responsible research team.
- UNLP project X1019: led by Gonzalo A. Torres Tejerizo, with María Carla Martini as a participating researcher. Also shown in Antimycobacterial Research.
- Previous project: PICT2020-02314, “Molecular basis of a new regulatory circuit involved in plasmid transfer in rhizobia”. ANPCyT; principal investigator Gonzalo A. Torres Tejerizo; completed according to the presentation.
- Fundación Williams 2024: “Experimental validation of determinants involved in bacterial differentiation into bacteroids for efficient nitrogen-fixing symbiosis”. Led by Gonzalo A. Torres Tejerizo; previously published in Genomics.
Selected scientific output
Selected publications associated with the group’s research areas and members. Work predating the reorganisation retains its institutional provenance; each shared publication has one catalogue record.
- Characterization of RcgA and RcgR, two rhizobial proteins involved in the modulation of plasmid transfer
- Comparative genomic analysis of Sinorhizobium meliloti LPU88: plasmid diversity and conjugative mechanisms
- The Complete Genome of Rhizobium favelukesii LPU83T: Insights into Plastic pSym and Its Symbiotic Incompatibility with a Broad Range of Legume Hosts
- Characterization and identification of Pseudomonas sp. AW4, an arsenic-resistant and plant growth-promoting bacteria isolated from the soybean (Glycine max L.) rhizosphere
- Characterization of an accessory plasmid of Sinorhizobium meliloti and its two replication-modules
Collaborations
- Bioinformatics, Bacterial Signal Transduction, Bacteria–Host Systems and Antimycobacterial Research groups.
- Julieta Pérez Giménez and Elías Mongiardini (IBBM); joint doctoral supervision of Catalina D'Addona and Ornella Falduti with Julieta Pérez Giménez.
- Adriana Alippi (FCAyF–UNLP), Julián Dib (PROIMI), Juan Ignacio Quelas (Y-TEC), Elizabeth Agostini (INBIAS), Tania Taurian and Federico Ibáñez (INIAB), and Mario Perelló (IMBICE).
- Karsten Niehaus, Alfred Pühler and Tobias Busche (Bielefeld University); David Romero (CCG–UNAM); Tea Pavkov-Keller (University of Graz); Kondorosi's group (Biological Research Centre, Hungary).
Capabilities
Bacterial genetics, mutagenesis, gene-expression and plasmid-transfer analysis, bacterium–plant interaction assays and integration of transcriptomics, proteomics and metabolomics.
Contact
Gonzalo Arturo Torres Tejerizo · gatt@biol.unlp.edu.ar