Chemical Cross-talk Research Articles

An Initial Exploration of Coupled Transient Mechanical and Electrochemical Behaviors in Lithium Ion Batteries

While lithium-ion batteries are the dominant technology in the energy storage market, aspects of these batteries remain a mystery. For example, better understanding of chemical and mechanical crosstalk, and transients thereof, may lead to increased cycle life and rate capability. Here, an ultrasound acoustic characterization technique is introduced to probe the electrode/electrolyte interface in operando using signal amplitude analysis. This technique gives insight into lithium-ion concentration accumulation and depletion at the electrode/electrolyte interface, and these findings are consistent with Dualfoil model simulations.

Epigenome – A mediator for host-microbiome crosstalk

The interaction between the gut and its eventual trillions of microbe inhabitants during microbial colonization, represents a critical time period for establishing the overall health and wellbeing of an individual. The gut microbiome represents a diverse community of microbes that are critical for many physiological roles of the host including host metabolism. These processes are controlled by a fine-tuned chemical cross talk between the host and microbiota. Although the exact mechanisms behind this cross talk remains elusive, microbiota induced epigenetic mechanisms like DNA methylation and histone modifications may be key. This review presents our perspective on the epigenome as a mediator for host-microbiota cross talk, as well as methodology to study epigenetics, the role of dysbiosis in disease, and how the gut microbiome-host axis may be used in personal medicine.

Responses to chemical cross-talk between the Mycobacterium ulcerans toxin, mycolactone, and Staphylococcus aureus

Buruli ulcer is a neglected tropical disease caused by the environmental pathogen, Mycobacterium ulcerans whose major virulence factor is mycolactone, a lipid cytotoxic molecule. Buruli ulcer has high morbidity, particularly in rural West Africa where the disease is endemic. Data have shown that infected lesions of Buruli ulcer patients can be colonized by quorum sensing bacteria such as Staphylococcus aureus, S. epidermidis, and Pseudomonas aeruginosa, but without typical pathology associated with those pathogens’ colonization. M. ulcerans pathogenesis may not only be an individual act but may also be dependent on synergistic or antagonistic mechanisms within a polymicrobial network. Furthermore, co-colonization by these pathogens may promote delayed wound healing, especially after the initiation of antibiotic therapy. Hence, it is important to understand the interaction of M. ulcerans with other bacteria encountered during skin infection. We added mycolactone to S. aureus and incubated for 3, 6 and 24 h. At each timepoint, S. aureus growth and hemolytic activity was measured, and RNA was isolated to measure virulence gene expression through qPCR and RNASeq analyses. Results showed that mycolactone reduced S. aureus hemolytic activity, suppressed hla promoter activity, and attenuated virulence genes, but did not affect S. aureus growth. RNASeq data showed mycolactone greatly impacted S. aureus metabolism. These data are relevant and significant as mycolactone and S. aureus sensing and response at the transcriptional, translational and regulation levels will provide insight into biological mechanisms of interspecific interactions that may play a role in regulation of responses such as effects between M. ulcerans, mycolactone, and S. aureus virulence that will be useful for treatment and prevention.

Role of High-Temperature Separator Stability on Safety and Thermal Signature of Li-Ion Pouch Cells

Thermal safety hazards are a bottleneck problem that constrains the development of lithium-ion batteries with high energy density. Although the internal short circuit (ISC) caused by separator rupture has been identified as a primary driver of catastrophic failure, the effects of separator architecture and high-temperature robustness on thermal runaway behaviors still need fundamental understanding. This study investigates custom-built pouch cells assembled with a wide range of separators to understand the impact of separators on cell-level thermal stability and resistance to catastrophic ISC. Carefully designed thermal abuse tests reveal how the separator shrinkage, melting, and collapse correlate with micro and massive ISC to drive the unstoppable thermal runaway. Cells are subjected to extreme operating conditions to facilitate quantification of the role of separator characteristics on the thermal runaway signature. The implications of separator distinctions on modulating chemical crosstalk between anode and cathode are explored to determine the dominant mechanism that triggers the onset of thermal runaway, with mitigation strategies being proposed from a new perspective.

Identifying metabolic pathway intermediates that modulate the gallate dioxygenase (DesB) from Sphingobium sp. strain SYK-6

Lignin is often considered an underutilized carbon source for the production of biofuels and other value-added compounds. Depolymerized lignin results in a collection of different aromatic compounds that have their own metabolic pathways for conversion into central metabolites. This investigation describes the chemical crosstalk of compounds between different metabolic pathways involved in the catabolism of lignin. Specifically, seven compounds were identified as inhibitors of the dioxygenase DesB. The most potent inhibitor, protocatechuate, moderately impacts both vmax and KM of DesB (71 s−1 and 167 μM versus 130 s−1 and 123 μM, in the presence and absence of protocatechuate, respectively) suggesting a mixed (competitive and non-competitive) inhibition profile. Molecular docking identified a putative allosteric pocket adjacent to the active site, in a position analogous to one identified previously for a related dioxygenase. This work demonstrates that lignin catabolic pathway intermediates can modulate the activity of multiple enzymes within the lignin degradation pathway and need to be considered when engineering organisms to utilize lignin for biomass conversion.

Mini-review: Trophic interactions between cancer cells and primary afferent neurons

Cancer neurobiology is an emerging discipline that inevitably unfurls new perspectives in oncology. The role that nerves play in cancer progression resonates with the long-reported dependency of tumors on neuro-molecular mechanisms that remain insufficiently elucidated. Whereas interactions between neurotrophic growth factors and receptors have been heavily studied in the nervous system, their expression in cancers and their impact on tumor cell growth and metastasis through their corresponding signaling pathways has been undervalued. Accumulating evidence suggests that trophic factors released by nerves strongly influence tumor development and that this neural contribution appears to not only play a stimulatory role but also function as an essential part of the tumor’s microenvironment. This bidirectional communication between proliferating cells and tumor-infiltrating nerves drives axonogenesis and tumor growth and migration. Acquiring a better understanding of the trophic interactions between primary afferent neurons and invading tumors will guide clinically actionable strategies to prevent tumor-associated axonogenesis, disrupting the chemical crosstalk between neurons and tumors and ultimately decreasing tumor growth and spread.

Determinants of Host Range Specificity in Legume-Rhizobia Symbiosis.

Leguminous plants possess the almost unique ability to enter symbiosis with soil-resident, nitrogen fixing bacteria called rhizobia. During this symbiosis, the bacteria physically colonize specialized organs on the roots of the host plant called nodules, where they reduce atmospheric nitrogen into forms that can be assimilated by the host plant and receive photosynthates in return. In order for nodule development to occur, there is extensive chemical cross-talk between both parties during the formative stages of the symbiosis. The vast majority of the legume family are capable of forming root nodules and typically rhizobia are only able to fix nitrogen within the context of this symbiotic association. However, many legume species only enter productive symbiosis with a few, or even single rhizobial species or strains, and vice-versa. Permitting symbiosis with only rhizobial strains that will be able to fix nitrogen with high efficiency is a crucial strategy for the host plant to prevent cheating by rhizobia. This selectivity is enforced at all stages of the symbiosis, with partner choice beginning during the initial communication between the plant and rhizobia. However, it can also be influenced even once nitrogen-fixing nodules have developed on the root. This review sets out current knowledge about the molecular mechanisms employed by both parties to influence host range during legume-rhizobia symbiosis.

Volatiles from soil‐borne fungi affect directional growth of roots

Volatiles play major roles in mediating ecological interactions between soil (micro)organisms and plants. It is well‐established that microbial volatiles can increase root biomass and lateral root formation. To date, however, it is unknown whether microbial volatiles can affect directional root growth. Here, we present a novel method to study belowground volatile‐mediated interactions. As proof‐of‐concept, we designed a root Y‐tube olfactometer, and tested the effects of volatiles from four different soil‐borne fungi on directional growth of Brassica rapa roots in soil. Subsequently, we compared the fungal volatile organic compounds (VOCs) previously profiled with Gas Chromatography–Mass Spectrometry (GC–MS). Using our newly designed setup, we show that directional root growth in soil is differentially affected by fungal volatiles. Roots grew more frequently toward volatiles from the root pathogen Rhizoctonia solani, whereas volatiles from the other three saprophytic fungi did not impact directional root growth. GC–MS profiling showed that six VOCs were exclusively emitted by R. solani. These findings verify that this novel method is suitable to unravel the intriguing chemical cross‐talk between roots and soil‐borne fungi and its impact on root growth.

Host and Pathogen Communication in the Respiratory Tract: Mechanisms and Models of a Complex Signaling Microenvironment.

Chronic lung diseases are a leading cause of morbidity and mortality across the globe, encompassing a diverse range of conditions from infections with pathogenic microorganisms to underlying genetic disorders. The respiratory tract represents an active interface with the external environment having the primary immune function of resisting pathogen intrusion and maintaining homeostasis in response to the myriad of stimuli encountered within its microenvironment. To perform these vital functions and prevent lung disorders, a chemical and biological cross-talk occurs in the complex milieu of the lung that mediates and regulates the numerous cellular processes contributing to lung health. In this review, we will focus on the role of cross-talk in chronic lung infections, and discuss how different cell types and signaling pathways contribute to the chronicity of infection(s) and prevent effective immune clearance of pathogens. In the lung microenvironment, pathogens have developed the capacity to evade mucosal immunity using different mechanisms or virulence factors, leading to colonization and infection of the host; such mechanisms include the release of soluble and volatile factors, as well as contact dependent (juxtracrine) interactions. We explore the diverse modes of communication between the host and pathogen in the lung tissue milieu in the context of chronic lung infections. Lastly, we review current methods and approaches used to model and study these host-pathogen interactions in vitro, and the role of these technological platforms in advancing our knowledge about chronic lung diseases.

Abundance and Extracellular Release of Phytohormones in Aero-terrestrial Microalgae (Trebouxiophyceae, Chlorophyta) As a Potential Chemical Signaling Source1.

Phytohormones are pivotal signaling compounds in higher plants, in which they exert their roles intracellularly, but are also released for cell‐to‐cell communication. In unicellular organisms, extracellularly released phytohormones can be involved in chemical crosstalk with other organisms. However, compared to higher plants, hardly any knowledge is available on the roles of phytohormones in green algae. Here, we studied phytohormone composition and extracellular release in aero‐terrestrial Trebouxiophyceae. We investigated (a) which phytohormones are produced and if they are released extracellularly, and if extracellular phytohormone levels are (b) affected by environmental stimuli, and (c) differ between lichen‐forming and non‐lichen‐forming species. Three free‐living microalgae (Apatococcus lobatus, Chloroidium ellipsoideum, and Myrmecia bisecta) and three lichen‐forming microalgae (Asterochloris glomerata, Trebouxia decolorans, and Trebouxia sp.) were studied. Algae were grown on solid media and the following cellular phytohormones were identified by ultra‐high‐performance liquid chromatography coupled with tandem mass spectrometry (UHPLC‐MS/MS): indole‐3‐acetic acid (IAA), indole‐3‐butyric acid (IBA), abscisic acid (ABA), gibberellin A4 (GA4), and zeatin (ZT). Furthermore, IAA, IBA, ABA, jasmonic acid (JA), gibberellin A3 (GA3), and GA4 were found to be released extracellularly. IAA and ABA were released by all six species, and IAA was the most concentrated. Phytohormone release was affected by light and water availability, especially IAA in A. glomerata, Trebouxia sp., and C. ellipsoideum. No clear patterns were observed between lichen‐forming and non‐lichen‐forming species. The results are envisaged to contribute valuable baseline information for further studies into the roles of phytohormones in microalgae.

Yucasin and cinnamic acid inhibit IAA and flavonoids biosynthesis minimizing interaction between maize and endophyte Aspergillus nomius

Chemical crosstalk between plant roots and associated microbes is imperative for the initiation of symbiosis. Phenolics, flavonoids and indole-3-acetic acid (IAA) are acclaimed as signaling molecules in developing plant-microbe symbiosis. The role of IAA and flavonoids in establishing a symbiotic relationship between Aspergillus nomius wlg2 and maize roots have also been observed during the present study. The isolate A. nomius wlg2 and maize roots have secreted flavonoids and IAA that helped in A. nomius-maize association. However, the suppression of either flavonoids or IAA secretion reduced the endophyte colonization of the maize roots by 77% and 67%, respectively. The main flavonoids secreted by maize were identified as luteolin, calycosin, phenolics cis-caftaric acid, and caffeoyl-d-glucose. The identified flavonoids were most likely to be involved in the root-endophyte association. To establish a plant-microbe interaction, the complex chemical dialogue is necessary for which IAA and flavonoids play a central role.

Chemical Structure, Biological Roles, Biosynthesis and Regulation of the Yellow Xanthomonadin Pigments in the Phytopathogenic Genus Xanthomonas.

Xanthomonadins are membrane-bound yellow pigments that are typically produced by phytopathogenic bacterial Xanthomonas spp., Xylella fastidiosa, and Pseudoxanthomonas spp. They are also produced by a diversity of environmental bacterial species. Considerable research has revealed that they are a unique group of halogenated, aryl-polyene, water-insoluble pigments. Xanthomonadins have been shown to play important roles in epiphytic survival and host-pathogen interactions in the phytopathogen Xanthomonas campestris pv. campestris, which is the causal agent of black rot in crucifers. Here, we review recent advances in the understanding of xanthomonadin chemical structures, physiological roles, biosynthetic pathways, regulatory mechanisms, and crosstalk with other signaling pathways. The aim of the present review is to provide clues for further in-depth research on xanthomonadins from Xanthomonas and other related bacterial species.

Astroglial Isopotentiality and Calcium-Associated Biomagnetic Field Effects on Cortical Neuronal Coupling.

Synaptic neurotransmission is necessary but does not sufficiently explain superior cognitive faculties. Growing evidence has shown that neuron–astroglial chemical crosstalk plays a critical role in the processing of information, computation, and memory. In addition to chemical and electrical communication among neurons and between neurons and astrocytes, other nonsynaptic mechanisms called ephaptic interactions can contribute to the neuronal synchronization from different brain regions involved in the processing of information. New research on brain astrocytes has clearly shown that the membrane potential of these cells remains very stable among neighboring and distant astrocytes due to the marked bioelectric coupling between them through gap junctions. This finding raises the possibility that the neocortical astroglial network exerts a guiding template modulating the excitability and synchronization of trillions of neurons by astroglial Ca2+-associated bioelectromagnetic interactions. We propose that bioelectric and biomagnetic fields of the astroglial network equalize extracellular local field potentials (LFPs) and associated local magnetic field potentials (LMFPs) in the cortical layers of the brain areas involved in the processing of information, contributing to the adequate and coherent integration of external and internal signals. This article reviews the current knowledge of ephaptic interactions in the cerebral cortex and proposes that the isopotentiality of cortical astrocytes is a prerequisite for the maintenance of the bioelectromagnetic crosstalk between neurons and astrocytes in the neocortex.

Epigenetic Regulation at the Interplay Between Gut Microbiota and Host Metabolism.

Gut microbiota communities have coevolved for millions of years in a symbiotic relationship with their mammalian hosts. Elucidating and understanding the molecular mechanisms by which microbiota interacts with its host and how this contributes to the homeostasis of the host is crucial. One of these molecular relationships is the so-called chemical crosstalk between microbiota and host metabolisms, including the poorly explored epigenetic regulation of host tissues by the metabolic activity of gut microbiota in response to changes in diet. DNA methylation and histone modifications are epigenetic marks partly regulated by enzymes such as methylases and acetylases, whose activity depend on host and microbiota metabolites that act as substrates and cofactors for these reactions. However, providing a complete mechanistic description of the regulatory interactions between both metabolisms and the impact on the expression of host genes through an epigenetic modulation, remains elusive. This article presents our perspective on how metabolomic, metagenomic, transcriptomic, and epigenomic data can be used to investigate the “microbiota–nutrient metabolism–epigenetics axis.” We also discuss the implications and opportunities this knowledge may have for basic and applied science, such as the impact on the way we structure future research, understand, and prevent diseases like type 2 diabetes or obesity.

The Microbiome of the Maculinea-Myrmica Host-Parasite Interaction

Maculinea (=Phengaris) are endangered butterflies that are characterized by a very complex biological cycle. Maculinea larvae behave as obligate parasites whose survival is strictly dependent on both particular food plants and species-specific Myrmica ants. In this interaction, Maculinea caterpillars induce Myrmica workers to retrieve and rear them in the nest by chemical and acoustic deception. Social insect symbiotic microorganisms play a key role in intraspecific and interspecific communication; therefore, it is possible that the Maculinea caterpillar microbiome might be involved in the chemical cross-talk by producing deceptive semiochemicals for host ants. To address this point, the microbiota of Maculinea alcon at different larval stages (phytophagous early larvae, intermediate larvae, carnivorous late larvae) was analyzed by using 16S rRNA-guided metabarcoding approach and compared to that of the host ant Myrmica scabrinodis. Structural and deduced functional profiles of the microbial communities were recorded, which were used to identify specific groups of microorganisms that may be involved in the chemical cross-talk. One of the most notable features was the presence in all larval stages and in the ants of two bacteria, Serratia marcescens and S. entomophila, which are involved in the chemical cross-talk between the microbes and their hosts.

Detrimental Effects of Chemical Cross-Talk in Rechargeable Lithium Metal Batteries

The energy density of conventional Li-ion batteries (LIBs) has eventually reached their theoretical limit. Increasing worldwide efforts have been made towards the next generation of energy storage systems including batteries using Li metal anode in combination with various cathodes, including intercalation compounds (such as NMC) or conversion materials (such as oxygen (O2) and sulfur (S)). For a full demonstration of new battery chemistries, the interfacial stability is essential to long cycle lifespan and battery performance. In general, batteries suffer from “cross-talk” processes upon cycling by the crossover of parasitic chemicals through the electrolyte media [1]. Indeed, "cross-talk" phenomena in Li-ion batteries, such as Mn2+ crossover from the cathode and contaminate graphite anode has been well established [2]. Li-S and Li-O2 batteries also have the shuttle issues of soluble redox-active materials, polysulfides and superoxide radical anions, respectively. However, the similar characteristics in Li metal batteries (LMBs) with conventional Li ion intercalation cathodes have rarely been studied. Therefore, an in-depth understanding of how a Li metal anode affects the cathode interface chemistry is critical to ensure the long-term cycling stability of LMBs. Here, we report the cathode failure triggered by the chemical “cross-talk” between the electrode pair in rechargeable LMBs. In sharp contrast to LIBs, the cathode in LMBs suffers more significant and irreversible capacity fade during cycling, and its capacity cannot be fully recovered in spite of repeated replacement with new Li metal in the successive cycling. In-depth characterizations of the cathode surface reveal severe deterioration of cathode electrolyte interphase related to the significant accumulation of highly resistive polymeric components and lithium fluoride. Extensive salt-anion decomposition at Li metal surface can cause the chemical aging of the electrolyte allowing the migration of soluble byproducts toward the cathode side, resulting in the severe deterioration of cathode and separator surfaces. A selective Li-ion permeable separator with polydopamine coating has been developed to mitigate the detrimental chemical crossover and enhance the cathode stability. [1] Mikhaylik, Y. V.; Akridge, J. R., Polysulfide Shuttle Study in the Li/S Battery System. J. Electrochem. Soc. 2004, 151 (11), A1969-A1976 [2] Vetter, J.; Novák, P.; Wagner, M. R.; Veit, C.; Möller, K. C.; Besenhard, J. O.; Winter, M.; Wohlfahrt-Mehrens, M.; Vogler, C.; Hammouche, A. Ageing mechanisms in lithium-ion batteries. J. Power Sources 2005, 147 (1), 269-281. Figure 1

Tuning Interfacial Processes in Mn-Based Li-Ion Systems Though Vapor Phase Modification

Among the different rechargeable battery technologies available, Co/Ni/Mn-based Li-ion systems appear to be a leading contender for automotive applications as a result of their high specific energy. However, the high operating potential of this system is outside the thermodynamic stability window of standard organic carbonate-based electrolytes. This results in electrolyte oxidation with transition metal dissolution and gas formation at the electrode/electrolyte interface during cycling, which leads to severe loss of electrochemical performance. To address these challenges, many strategies are currently being investigated, ranging from the development of new electrodes and electrolytes to the improvement of commercial Li-ion systems by surface engineering of the interfaces.In this work, we mitigate parasitic interfacial processes in start/stop batteries by atomic layer deposition (ALD). We develop an Al2O3 or LiPON conformal artificial SEI layer on LMO and LTO electrodes and study its effect on the Li-ion batteries failure modes with differential electrochemical mass spectroscopy (DEMS), X-ray Photoelectron Spectroscopy (XPS) and ICP measurements. The beneficial impact of the protection layer on the kinetics of the gassing, metal dissolution and associated chemical cross-talk was clearly identified. The presence of a protection layer at the LMO surface, in particular of a 10 nm LiPON conformal layer, mitigate the electrolyte oxidation at high voltage at 60°C with a significant reduction of the amount of H2 produced. The formation of metal complexes and subsequent poisoning of the SEI is also attenuated. Interestingly, counter intuitively, the ratio of the inorganic to organic components of the SEI is lowered by the presence of an inorganic protection layer. The correlation between the nature of the electrode protection layer, the electrode’s surface activity, and associated organic electrolyte oxidation pathways will be presented and discussed. Acknowledgement This work was supported by SAFT and as part of the Nanostructures for Electrical Energy Storage (NEES), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science.

Safety First

Safety First

Abstract B062: Proteomic characterization of the secretome from prostate cancer and bone progenitor cell coculture

Abstract Prostate cancer (PCa) is one of the most frequent sites of primary tumor development in human beings. PCa tumor cells tend to disseminate to and form metastatic lesions in the bone. Given the evident prevalence and clinical significance of bone metastases, unraveling the mechanisms exploited by cancer to form these destructive lesions is of critical interest. This is partly due to the fact that the metastatic cascade encompasses many rate-limiting steps demanding tumor cells to employ new mechanisms at each stage. Our work aimed at evaluating which soluble factors could mediate the chemical crosstalk between PCa cells and bone progenitor cells. For this purpose, we used coculture transwell systems of PC3 (human PCa cells) with the preosteoclastic Raw264.7 or preosteoblastic MC3T3 cell lines (murine cells), where cells shared the culture media (CMs) without physical contact for 24h. We employed mass spectrometry—nanoLC-MS/MS(Orbitrap) —for the secretome analysis of the CMs. The obtained spectra were analyzed with the Proteome Discover Software and compared with both human and murine protein databases. Results highlight a differential secretome profile released to the CM when tumor cells are grown in coculture compared to controls. These results could potentially explain the altered mRNA expression levels assessed by RTqPCR in PCa cells growing in coculture, displaying significant upregulation for HO-1 ANXA2, ANXA2R, OPG, and PTHrP (p<0.05). Of note, coculture secretomes showcase highly bone-associated proteins released by tumoral cells such as periostin, cartilage oligomeric matrix protein, OPN, BMP and ILGF-II, IL-7, FGF, Mx-1—involved in prostate carcinogenesis—compared to controls, evidencing a misregulated microenvironment. These results may offer a better understanding of the molecular affinity between PCa cells and the bone microenvironment, allowing the improvement of PCa patient prognosis Citation Format: Nicolás Anselmino, Alejandra Páez, Sofía Lage Vickers, Javier Cotignola, Pía Valacco, Geraldine Gueron, Elba Vázquez. Proteomic characterization of the secretome from prostate cancer and bone progenitor cell coculture [abstract]. In: Proceedings of the AACR Special Conference: Prostate Cancer: Advances in Basic, Translational, and Clinical Research; 2017 Dec 2-5; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(16 Suppl):Abstract nr B062.

Relevance of the deletion of the Tatri4 gene in the secondary metabolome of Trichoderma arundinaceum.

The fungus Trichoderma arundinaceum (Ta37) has a significant biocontrol application which has been related to the production of the trichothecene, harzianum A (2). Previous studies with a strain of T. arundinaceum which was blocked for the production of 2, revealed the existence of a chemical cross-regulation between the biocontrol fungus and its target organism. A study of the secondary metabolome of a single culture of a mutant of T. arundinaceum TaΔTri4 which produces trichothecene biosynthetic intermediates, has now been carried out. The production of secondary metabolites in a co-culture with the phytopathogen, Botrytis cinerea, was then analyzed. The mutant produced a larger quantity of the aspinolides B (6) and C (7) and other derivatives when compared to the wild type Ta37. Ten new metabolites were isolated: three aspinolides 12-14, the γ-lactones 15 and 16, two hemi-ketals 17 and 18 and three aspinolide degradation products, 19, 21 and 22. In the confrontation cultures involving the TaΔTri4 and the B. cinerea B05.10 strains, there was a higher production of the aspinolides B and C by the TaΔTri4 mutant while the production of the botryanes and botcinins by B. cinerea was reduced in the area of interaction between the cultures. These results shed light on the chemical cross-talk and ecological interactions between these fungi.