Biology subjects

Perez-Lorente, A. I.

Publications and source records attributed to Perez-Lorente, A. I..

4 recordsLinked to original sources

bioRxiv2026

Cooperative siderophore use stabilizes a protective leaf microbiome

Plant-associated microbial communities provide crucial protection against pathogens. Specialized metabolites play key roles in plant-microbe and microbe-microbe interactions and, ultimately, in plant health; however, the molecular mechanisms underlying their plant-protecting properties remain largely unknown. Nutrient deficiency (e.g., iron) on leaf surfaces creates intense competition among microbes, driving both antagonism and cooperation. Using a gnotobiotic Arabidopsis thaliana model and a synthetic leaf microbial community, we show that community stability and plant protection depend on cooperative siderophore exchange between the basidiomycete yeast Rhodotorula kratochvilovae and commensal Pseudomonas species. Removal of Pseudomonas caused a strong shift in the community metabolome and accumulation of the yeast siderophore rhodotorulic acid (RA). RA selectively promoted the growth of commensal Pseudomonas via TonB-dependent transporters, which are absent in pathogenic Pseudomonas strains. Inactivation of these transporter genes abolished RA uptake, destabilized the synthetic community, and eliminated protection against Pseudomonas syringae infection. RA and Rhodotorula also induced host iron-deficiency and jasmonate-related defense metabolites, linking microbial cooperation to plant stress responses. These findings reveal that microbial siderophore exchange acts as a key mechanism that maintains stability in the phyllosphere microbiome. Rather than solely promoting competition, iron-binding compounds can serve as cooperative currencies that align microbial fitness with host protection.

microbiology↗

bioRxiv2023

Cyclo(Pro-Tyr) elicits conserved cellular damage in fungi by targeting the ATPase Pma1 in plasma membrane domains

Bioactive metabolites play a crucial role in shaping interactions among diverse organisms. In this study, we identified cyclo(Pro-Tyr), a metabolite produced by Bacillus velezensis, as a potent inhibitor of Botrytis cinerea and Caenorhabditis elegans, two potential cohabitant eukaryotic organisms. Based on our investigation, cyclo(Pro-Tyr) disrupts plasma membrane polarization, induces oxidative stress and increases membrane fluidity, which compromises fungal membrane integrity. These cytological and physiological changes induced by cyclo(Pro-Tyr) may be triggered by the destabilization of membrane microdomains containing the [H+]ATPase Pma1. In response to cyclo(Pro-Tyr) stress, fungal cells activate a transcriptomic and metabolomic response, which primarily involves lipid metabolism and Reactive Oxygen Species (ROS) detoxification, to mitigate membrane damage. This similar response occurs in the nematode C. elegans, suggesting that cyclo(Pro-Tyr) universally targets eukaryotic cellular membranes.

microbiology↗

bioRxiv2022

A non-invasive method for time-lapse imaging of microbial interactions and biofilm dynamics

Complex interactions between microbial populations can greatly affect the overall properties of a microbial community, sometimes leading to cooperation and mutually beneficial coexistence, or to competition and the death or displacement of particular organisms or sub-populations. Interactions between different biofilm populations are highly relevant in diverse scientific areas, from antimicrobial resistance to microbial ecology. The utilization of modern microscopic techniques has provided new and interesting insight into how bacteria interact at the cellular level to form and maintain microbial biofilms. However, our ability to follow complex intra- and inter-species interactions in vivo at the microscopic level has remained somewhat limited. Here, we detail BacLive, a novel non-invasive method for tracking bacterial growth and biofilm dynamics using high resolution fluorescence microscopy and an associated ImageJ processing macro (https://github.com/BacLive) for easier data handling and image analysis. Finally, we provide examples of how BacLive can be used in the analysis of complex bacterial communities. ImportanceCommunication and interactions between single cells are continuously defining the structure and composition of microbial communities timely and spatially. Methods routinely used to the study of these communities at cellular level rely on sample manipulation what deprives from microscopic time lapse experiments on a given sample. BacLive is conceived as a method for the non-invasive study of the formation and development of bacterial communities, such as biofilms, and the dynamics of formation of specialized subpopulations in time-lapse experiments. In addition we prove that BacLive largely simplifies the analysis of the data generated.

microbiology↗

bioRxiv2022

Sporulation activated via σW protects Bacillus from a Tse1 peptidoglycan hydrolase T6SS effector

Bacterial communities constantly interact with various community members employing diverse offensive and defensive tools to reach coexistence. The extracellular matrix and sporulation are defensive mechanisms used by Bacillus cells when they interact with Pseudomonas strains expressing a type VI secretion system (T6SS). Here, we define Tse1 as the main toxin mobilized by the Pseudomonas T6SS that triggers sporulation in Bacillus. We characterize Tse1 as a peptidoglycan hydrolase that indirectly alters the dynamics and functionality of the Bacillus cell membrane. We also delineate the response of Bacillus cells to Tse1, which through the coordinated actions of the extracellular sigma factor {sigma}W and the cytoplasmic histidine kinases KinA and KinB, culminates in activation of the sporulation cascade. We propose that this cellular developmental response is conserved in Bacilli to defend against the toxicity of T6SS-mobilized Tse1 effector.

microbiology↗