A5004638012- Legume Nitrogen Fixing Symbiosis
- Plant nutrient uptake and metabolism
- Agronomic Practices and Intercropping Systems
- Nematode management and characterization studies
- Soil Carbon and Nitrogen Dynamics
- Photosynthetic Processes and Mechanisms
- Microbial Community Ecology and Physiology
- Bacterial Identification and Susceptibility Testing
- Microbial Fuel Cells and Bioremediation
- Wastewater Treatment and Nitrogen Removal
- Trace Elements in Health
- Fungal Infections and Studies
- Bacterial Genetics and Biotechnology
- PARP inhibition in cancer therapy
- Cassava research and cyanide
- Plant Pathogens and Fungal Diseases
- Plant Parasitism and Resistance
- Mitochondrial Function and Pathology
- Redox biology and oxidative stress
- Protein Structure and Dynamics
- DNA Repair Mechanisms
- Protist diversity and phylogeny
- Genomics and Phylogenetic Studies
- Toxin Mechanisms and Immunotoxins
- Diphtheria, Corynebacterium, and Tetanus
University of Oxford
2020-2025
ETH Zurich
2014-2022
German Cancer Research Center
2017
Heidelberg University
2017
Paul Scherrer Institute
2014
University of Zurich
2014
ABSTRACT Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) is increasingly used for the identification bacteria and fungi in diagnostic laboratory. We evaluated mold database Bruker Daltonik (Bremen, Germany), Filamentous Fungi Library 1.0. First, we studied 83 phenotypically molecularly well-characterized, nondermatophyte, nondematiaceous molds from a clinical strain collection. Using manufacturer-recommended interpretation criteria, genus species...
Significance Rhizobia are soil-dwelling bacteria that form symbioses with legumes and provide biologically useable nitrogen as ammonium for the host plant. High-throughput DNA sequencing has led to a rapid expansion in publication of complete genomes numerous rhizobia, but analysis gene function increasingly lags discovery. Mariner-based transposon insertion allowed us characterize fitness contribution bacterial genes determine those functionally important Rhizobium– legume symbiosis at...
Significance Legumes, like peas, beans, and lentils, are high in protein because they form associations with specialized nitrogen-fixing bacteria. Plants provide the bacteria carbon receive nitrogen return, but some bacterial strains more than others. We show that pea plants supply resources to poor at fixing only if have no other choice. If a better strain is present, withheld. This indicates legumes can make conditional decisions, giving them remarkable control over their symbiotic...
Modification of nucleic acids by ADP-ribosylation is catalyzed various ADP-ribosyltransferases, including the DarT enzyme. The latter part bacterial toxin-antitoxin (TA) system DarTG, which was shown to provide control DNA replication and growth as well protection against bacteriophages. Two subfamilies have been identified, DarTG1 DarTG2, are distinguished their associated antitoxins. While DarTG2 catalyzes reversible thymidine bases employing a macrodomain antitoxin, activity biochemical...
Rhizobia are a phylogenetically diverse group of soil bacteria that engage in mutualistic interactions with legume plants. Although specifics the symbioses differ between strains and plants, all ultimately result formation specialized root nodule organs host nitrogen-fixing microsymbionts called bacteroids.
Abstract Background After two decades of extensive microbiome research, the current forefront scientific exploration involves moving beyond description and classification to uncovering intricate mechanisms underlying coalescence microbial communities. Deciphering assembly has been technically challenging due their vast diversity but establishing a synthetic community (SynCom) serves as key strategy in unravelling this process. Achieving absolute quantification is crucial for causality...
Bradyrhizobium diazoefficiens USDA 110 (formerly named japonicum) can fix dinitrogen when living as an endosymbiont in root nodules of soybean and some other legumes. Formation a functional symbiosis relies on defined developmental program mediated by controlled gene expression both symbiotic partners. In contrast to well-studied Rhizobium-legume model systems that have been thoroughly examined means genetically tagged strains, analysis B. host infection has impaired due the lack suitable...
Abstract Peptidoglycan is an essential component of the bacterial cell envelope—a mesh-like macromolecule that protects bacterium from osmotic stress and its internal turgor pressure. The composition architecture peptidoglycan heterogeneous changes as bacteria grow, divide, respond to their environment. Though has long been studied via LC-MS/MS, analysis this data remains challenging peptidoglycan’s unusual branching can’t be handled by proteomics software. Here we describe user-friendly...
Phylogenetically diverse bacteria respond to various stress conditions by mounting a general response (GSR) resulting in the induction of protection or damage repair functions. In α-proteobacteria, GSR is induced regulatory cascade consisting extracytoplasmic function (ECF) σ factor EcfG , its anti-σ NepR, and anti-anti-σ PhyR. We have reported previously that PhyR Bradyrhizobium diazoefficiens (formerly named japonicum), nitrogen-fixing root nodule symbiont soybean related legumes, are...
The adaptation of rhizobia from the free-living state in soil to endosymbiotic comprises several physiological changes order cope with extremely low oxygen availability (microoxia) within nodules. To uncover cellular functions required for bacterial microoxia directly at protein level, we applied a systems biology approach on key rhizobial model and soybean endosymbiont Bradyrhizobium diazoefficiens USDA 110 (formerly B. japonicum 110). As first step, complete genome 110spc4, strain used...
We demonstrate how two copper atoms are brought together to build a metal center in an essential enzyme for cellular respiration.
The plant common symbiosis signalling (SYM) pathway has shared function between interactions with rhizobia and arbuscular mycorrhizal fungi, the two most important symbiotic plants microorganisms that are crucial in agricultural yields. Here, we determine role of SYM structure abundance microbiota model legume Medicago truncatula whether this is controlled by nitrogen or phosphorus status plant. We show mutants (dmi3) differ substantially from wild type (WT) absolute root microbiota,...
Analysis of bacterial gene function commonly relies on disruption or replacement followed by phenotypic characterization the resulting mutant strains. Deletion targeted regions is achieved via two homologous recombination (HR) events between genome and a nonreplicating plasmid carrying DNA fragments flanking region to be deleted. The counterselection clones that have integrated entire in their single HR event crucial this procedure. Various genetic tools well-established protocols are...
The Bradyrhizobium -soybean symbiosis is of great agricultural significance and serves as a model system for fundamental research in bacterium-plant interactions. While detailed molecular insight available about mutual recognition early nodule organogenesis, our understanding the host-imposed conditions physiology infecting rhizobia during transition from free-living state rhizosphere to endosymbiotic bacteroids currently limited.
Bacterial persistence in the rhizosphere and colonization of root niches are critical for establishment many beneficial plant-bacteria interactions including those between Rhizobium leguminosarum its host legumes. Despite this, most studies on R. have focused symbiotic lifestyle as an endosymbiont nodules. Here, we use random barcode transposon sequencing to assay gene contributions during competitive growth various plant species. This facilitated identification 189 genes commonly required...
Rhizobia, such as B. diazoefficiens , play an important role in the nitrogen cycle by making gas bioavailable through symbiosis with legume plants. As climate change threatens soil health, this has received increased attention a more sustainable source of than energy-intensive Haber-Bosch process.
Rhizobium leguminosarum aspartate aminotransferase (AatA) mutants show drastically reduced symbiotic nitrogen fixation in legume nodules. Whilst AatA reversibly transaminates the two major amino-donor compounds and glutamate, reason for lack of N 2 mutant has remained unclear. During our investigations into role AatA, we found that it catalyses an additional transamination reaction between pyruvate, forming alanine. This secondary runs at around 60 % canonical transaminase rate connects...
The general stress response (GSR) enables bacteria to sense and overcome a variety of environmental stresses. In alphaproteobacteria, stress-perceiving histidine kinases the HWE HisKA_2 families trigger signaling cascade that leads phosphorylation regulator PhyR and, consequently, activation GSR σ factor EcfG . nitrogen-fixing bacterium Bradyrhizobium diazoefficiens, are crucial for tolerance against stresses under free-living conditions also efficient infection its symbiotic host soybean....
Abstract By analyzing successive lifestyle stages of a model Rhizobium -legume symbiosis using mariner-based transposon insertion sequencing (INSeq), we have defined the genes required for rhizosphere growth, root colonization, bacterial infection, N 2 -fixing bacteroids and release from legume (pea) nodules. While only 27 are annotated as nif fix in leguminosarum , show 603 genetic regions (593 genes, 5 tRNAs RNA features) competitive ability to nodulate pea . Of these, 146 common growth...