Biology subjects

Wagner, T.

Publications and source records attributed to Wagner, T..

At least 19 recordsLinked to original sources

bioRxiv2026

Trypanosomal MICOS is assembled on non-respiring mitochondrial crista precursors and associates with two integral microproteins

The mitochondrial contact site and cristae organizing system (MICOS) is a multiprotein complex that shapes crista junctions and maintains inner and outer membrane contacts. MICOS coordinates the assembly of electron transport chain complexes, a prerequisite for cellular respiration. Indeed, MICOS is lost in eukaryotes that dispensed with cellular respiration, suggesting that its assembly depends on the presence of an active respiratory chain. Trypanosoma brucei provides a unique system to test this hypothesis as its mitochondrion undergoes developmentally regulated remodeling. In the insect stage, the mitochondrion contains cristae with an active electron transport chain, whereas the mammalian bloodstream form possesses precursor cristae with stub-like morphology that lack respiratory activity. MICOS has been characterized in the insect stage but remains unexamined in the bloodstream form. Here, we demonstrate that all MICOS subunits assemble onto precursor cristae, retaining conserved interactions with both outer and inner membrane protein machineries. This is somewhat unexpected given the co-occurrence of MICOS with active cellular respiration in nature. Furthermore, we identify novel MICOS-associated proteins that are dispensable for its stability, suggesting auxiliary rather than core roles in MICOS function. Together, our findings establish that MICOS assembly precedes cellular respiratory competence and expand its interaction landscape in trypanosomatids.

cell biology↗

bioRxiv2026

Loss of either RASSF1A alone or in combination with Caveolin-1 inhibition is associated with different premalignant histopathological alterations in the mammary glands of transgenic mice

Analyses of human breast carcinomas (BCs) and premalignant breast lesions show that the loss of RASSF1A is an early event in the development of ER+ BCs, which correlates linearly with malignant progression. This observation suggests that RASSF1A inhibition is important for the development and progression of ER+ BCs. In addition to RASSF1A, concurrent caveolin-1 (Cav-1) inhibition may further promote ER+ breast carcinogenesis. In the present study, transgenic Rassf1a-/- and Cav-1(-/-) single as well as Rassf1a-/-, Cav-1(-/-) double knockout mice were used to investigate the impact of single or combined Rassf1a and Cav-1 inactivation on BC initiation. Loss of either one or both proteins led to different, pre-malignant histopathological alterations within the mammary glands of the mice, but not to fully developed BC, confirming that Rassf1a and Cav-1 are both important for maintaining the integrity of mammary gland epithelial structure, but suggesting that further intracellular changes or extracellular factors are required for the development of luminal BC when both genes are lost.

cancer biology↗

bioRxiv2026

Reconstructing the hyphosphere using a hyphal release-capture soil microcosm

Fungal hyphae form spatially confined interfaces in soil that mediate close associations with bacteria, collectively referred to as the hyphosphere. Despite its recognized ecological importance, experimental access to hyphosphere-associated microbial communities under realistic soil and plant-associated conditions has remained limited. Here, we present a soil-mimetic microcosm that enables controlled reconstruction and recovery of hyphosphere bacterial communities embedded within plant-associated soil. The system integrates field-derived soil, a native soil microbial inoculum, living cotton seedlings, and a spatially constrained fungal inoculum housed within sterile cell-strainer assemblies, permitting hyphal extension into soil while preserving a recoverable fungal-soil boundary. Using the soil-borne plant pathogen Fusarium oxysporum f. sp. vasinfectum as a model filamentous fungus, we show that the microcosm enables reproducible recovery of hypha-associated soil microaggregates containing physically attached bacterial cells. Full-length 16S rRNA profiling revealed pronounced reductions in bacterial richness and evenness in hyphosphere samples relative to bulk and rhizosphere soils, consistent with recruitment of a restricted subset of the surrounding microbiota. Ordination analyses demonstrated clear compositional separation between soil and hyphosphere compartments, with convergence of hypha-associated communities across bulk and rhizosphere contexts. Phylogenetic turnover analyses indicated phylogenetic structuring, whereas taxonomic analyses identified a conserved set of bacterial genera consistently associated with hyphae alongside compartment-specific taxa influenced by soil and plant context. Together, these findings establish the novel hyphal release-and-capture microcosm as a reproducible, ecologically grounded platform for studying hyphosphere-associated bacterial communities in plant-associated soils.

microbiology↗

bioRxiv2025

Molecular mechanism of nitrogenase sequestration by a PII-protein couple

The microbial process of N2-fixation is crucial for the planetary nitrogen cycle and biosphere, but requires substantial cellular energy resources. Here, we solved how energy-limited anaerobes regulate on-demand N2-fixation by sequestering their nitrogenase through the PII-nitrogen regulatory proteins NifI1 and NifI2. The nitrogenase was directly isolated from a methanogenic archaeon, with NifI proteins tightly bound. The crystal structure of the inhibited form, refined to 2.3-[A] resolution, reveals a supercomplex in which three NifI1,2 units made of a NifI1,2 heterohexamer captured three nitrogenases via tentacular T-loops. Additional structural information confirmed that NifI1,2 sits at the nitrogenase reductase-binding site, preventing N2-reduction. The presence of MgATP and 2-oxoglutarate releases NifI1,2 from the nitrogenase core via a conformational switch of the T-loops, provoking a steric repulsion and loss of contacts. The overall molecular depiction corroborates previous genetic, biochemical, and biophysical experiments, proposing that NifI1,2 disrupts the dynamic nitrogenase-reductase association, thereby interfering with electron delivery for N2-fixation and preventing ATP consumption. While ligand-binding mode and the T-loop conformational switch are expected to be conserved among NifI1,2-utilisers, the association mode with the nitrogenase comes in different flavours as a few substitutions in NifI2 break NifI1,2 intramolecular dimerisation in Methanosarcinales species, readjusting the supercomplex without altering the inhibition mechanism. With the NifI1,2 allosteric control dependent on the alarmone 2-oxoglutarate, anaerobes can effectively balance nitrogen-acquisition versus energy-expenditure, a regulatory switch that might be primitive and has been progressively lost in non-energy-limited aerobes, but could inspire biotechnological engineering to optimise ammonia bioproduction.

biochemistry↗

bioRxiv2025

Molecular basis of N2 fixation in a hyperthermophilic archaeon

Exploring the natural diversity of phylogenetically distant nitrogenases is crucial for gaining new insights into the mechanism of atmospheric N2 fixation and unlocking biotechnological developments in sustainable ammonia production. Here, we investigated the N2-fixing system of Methanocaldococcus infernus, a deep-sea hyperthermophilic archaeon growing diazotrophically at 92 {degrees}C. This natively isolated nitrogenase has a melting temperature close to the water boiling point, with an extrapolated specific activity superior to mesophilic homologues. The crystal structures obtained at near-atomic resolution present the most simplified known nitrogenase, harbouring strategic hot spots for thermostability. It combines the structural traits of all three known nitrogenase isoforms, reinforcing the postulate that the archaeal enzyme predates modern versions. In contrast to structural homologues, the electron-transferring metallocofactor "P-cluster" is trapped in a rare state awaiting electron delivery, providing a detailed picture of the physiological state. The active site, harbouring the FeMo-cofactor catalyst, exhibits a mixture of the resting and "turnover" states, previously described solely in the bacterial vanadium and iron-only nitrogenases. Therefore, these results unify a mechanistic principle of all nitrogenases and highlight the advantages of the hyperthermostable nature of the archaeal enzyme, opening new avenues for further understanding of how nature splits the N2 triple bond.

biochemistry↗

bioRxiv2025

Endogenous Real Time Imaging Reveals Dynamic Chromosomal Mobility During Ligand-Mediated Transcriptional Burst Events

Enhancers serve as the major genomic elements regulating mammalian signal-dependent transcriptional programs, characterized by alternating periods of target gene "bursting" and "non-busting" that require investigation of induced enhancer condensates and locus motility in real time to provide dynamic insights into signal/ligand-dependent regulatory events. Here, endogenous live cell imaging has revealed the altered chromosomal dynamics/condensate formation occurring during estrogen receptor (ER)-dependent target gene bursting/post-bursting and chronic activation events. Simultaneous DNA/RNA endogenous live imaging reveals that an increased mobility of acutely ER-stimulated loci observed during the bursting phase is, unexpectedly, further increased in the subsequent non-burst phase. Single molecule tracking (SMT) of ER shows that the relatively high-burst, lower-mobility acute state was indeed enriched for high-viscosity, 1,6-hexanediol-sensative ER molecules in a low sub-diffusive confined state with enhanced condensate formation during burst activation. Consistent with this, blocking transcription with flavopiridol shifts DNA tracks into a non-confined state. Differential DNA kinetics during burst vs non-burst has provided a strategy to assess altered condensate formation during gene activation events. (165)

molecular biology↗

bioRxiv2025

Mini-bacterioferritins: Structural insight into a new type of ferritin-like protein from an anaerobic methane-oxidising archaeon

Ferritins are ubiquitous among life forms, as they are essential for iron homeostasis. Here, we unveiled a novel member of the ferritin family, baptised mini-bacterioferritin. The characterised mini-bacterioferritin was isolated from a microbial enrichment dominated by the methanotrophic archaeon Candidatus Methanoperedens BLZ2. Its atomic resolution crystal structure reveals a 12-mer assembly with a diiron ferroxidase centre located within a four-helix bundle. Redox cycling experiments on protein crystals reveal a shift in iron position at the active site, which follows the established ferritin catalytic cycle. The 12-mer sphere-like structure harboured six Fe-coproporphyrin III ligands, positioned at the interdimeric interface, a characteristic previously only found in 24-mer bacterioferritins. Phylogenetics, together with structure predictions of closely related proteins, revealed that mini-bacterioferritins form a new clade within the ferritin family that might conserve ancestral traits. Future research will need to investigate the physiological roles of these enzymes, which were unsuspectingly widely distributed among prokaryotes. TeaserA novel ferritin family, the heme-binding mini-bacterioferritin, assembles as a dodecamer and is widely distributed among microbes.

biochemistry↗

bioRxiv2025

Modulation of collagen-binding integrins affects fibroblast activation and inhibits fibrosis

The extracellular matrix contributes to the progression of several diseases, sometimes by disrupting organ function such as in lung and liver fibrosis. Because integrin receptors mediate cell-matrix interactions, we conditionally deleted {beta}1 integrin in murine hepatocytes in vivo. Increased TGF-{beta} and matrix deposition ensued. Application of a cyclic peptide (GLQGE) that binds to both 10{beta}1 and 11{beta}1 diminished fibrosis in two murine models. In liver fibrosis, TGF-{beta} production was reduced. In lung fibrosis, however, the effect was exclusively due to suppressing fibroblast activation and hence collagen production without TGF-{beta} involvement. In summary, integrin manipulation successfully changed cell behavior, with effects differing depending on the cell type. Importantly, it is possible to directly suppress fibroblast activation and consequently diminish matrix production independent of disease pathogenesis. This underscores the importance of matrix composition in modifying the behavior of embedded cells and hence disease severity. Key findingsO_LILoss of 11{beta}1 integrin-mediated signal in hepatocytes increases TGF-{beta} and leads to fibrosis C_LIO_LIEngaging 10{beta}1 and/or 11{beta}1 with a cyclic peptide (GLQGE) inhibits fibroblast activation directly and, consequently matrix production and progression of fibrosis C_LI

cell biology↗

bioRxiv2025

Atomic resolution structures of key enzyme MCR in anaerobic methanotrophy reveal novel and extensive post-translational modifications.

Anaerobic methanotrophic archaea (ANME) are crucial to planetary carbon cycling. They oxidise methane in anoxic niches by transferring electrons directly to nitrate or metal oxides and alternatively to sulfate-reducing bacteria. Due to their physiological complexity, no ANME species have been isolated, hampering the biochemical investigation of the enzymatic processes involved in anaerobic methane oxidation. To study the methane-capturing enzyme of these microorganisms, we circumvented the isolation barrier by exploiting microbial enrichments of freshwater nitrate-reducing ANME-2d grown in bioreactors, and marine ANME-2c in syntrophy with bacterial partners. The crystal structures of their Methyl-Coenzyme M Reductases (MCRs), refined to true atomic resolution, provided the most precise image of the enzyme to date. Despite their physiological differences, these ANMEs have extremely conserved MCR structures, similar to homologs from methanogenic Methanosarcinales, rather than the phylogenetically distant MCR of ANME-1 isolated from Black Sea mats. The three studied MCRs are highly modified, with seven post-translational modifications. Among them was a novel 3(S)-methylhistidine on the {gamma}-chain of both ANME-2d MCRs. Labelling with gaseous krypton did not reveal any internal channels that would facilitate alkane diffusion to the active site as observed in the ethane-specialized enzyme. Based on our data, the methanotrophic MCRs should follow the same radical reaction mechanism proposed for the methane-generating homologues. The described pattern of post-translational modifications underscores the importance of native purification as a powerful approach to discovering intrinsic enzymatic features in uncultivated microorganisms existing in nature.

microbiology↗

bioRxiv2024

Palatability of Insecticides and Protein in Sugar Solutions to Argentine Ants

Invasive ant species like Linepithema humile cause significant ecological and economic harm, making effective control strategies essential. Insecticide baits are currently the most effective approach for controlling ants. Therefore, quantifying how palatable or unpalatable baits, bait additives, or toxicants are, is critical for developing effective control methods. It has recently been demonstrated that in the comparative evaluation of foods, animals that are aware of both a test food and a comparator food exhibit greatly increased sensitivity when detecting the unpalatability of liquid baits. Here, we deploy a newly developed comparative evaluation methodology to examine the palatability to L. humile workers of three toxicants used in invasive ant control: Fipronil, spinosad, and imidacloprid, as well as egg white protein. Ants showed no significant preference between pure sucrose and sucrose-toxicant solutions, indicating that they either cannot detect the toxicants or that they do not find them distasteful. Survival tests confirmed that the toxicant concentrations used were lethal, with a survival rate of 50% or below after 72 hours. However, ants found egg protein additive unpalatable, significantly preferring pure sucrose to a sucrose-egg protein mix. These findings confirm that three major toxicants are suitable for use in baits, and that reported abandonment or avoidance of toxic baits is not due to the unpalatability of these toxicants. However, the addition of egg protein to sucrose baits, even at ratios which optimise colony growth, is likely counterproductive. Future research should investigate the relative preference of invasive ants for various bait matrixes over naturally available food, ensuring more effective pest management strategies.

animal behavior and cognition↗

bioRxiv2024

Snapshots of acetyl-CoA synthesis, the final step of CO2 fixation in the Wood-Ljungdahl pathway

In the ancient microbial Wood-Ljungdahl pathway, CO2 is fixed in a multi-step process ending with acetyl-CoA synthesis at the bifunctional carbon monoxide dehydrogenase/acetyl-CoA synthase complex (CODH/ACS). Here, we present catalytic snapshots of the CODH/ACS from the gas-converting acetogen Clostridium autoethanogenum, characterizing the molecular choreography of the overall reaction including electron transfer to the CODH for CO2 reduction, methyl transfer from the corrinoid iron-sulfur protein (CoFeSP) partner to the ACS active site and acetyl-CoA production. Unlike CODH, the multidomain ACS undergoes large conformational changes to form an internal connection to the CODH active site, accommodate the CoFeSP for methyl transfer and protect the reaction intermediates. Altogether, the structures allow us to draw a detailed reaction mechanism of this enzyme crucial for CO2 fixation in anaerobic organisms. One-Sentence Summary: Structural description of key states of CO2 fixation by the carbon monoxide dehydrogenase/acetyl-CoA synthase complex.

biophysics↗

bioRxiv2024

Carbon monoxide-driven bioethanol production operates via a tungsten-dependent catalyst

Microbial alcohol production from waste gasses is a game changer for sustainable carbon cycling and remediation. While the biotechnological process employing Clostridium autoethanogenum to transform syngas (H2/CO2/CO) is blooming, the reactions involved in ethanol biosynthesis remain to be demonstrated. Here, we experimentally showed that ethanol production initiates via a tungsten-dependent aldehyde:ferredoxin oxidoreductase (AFOR), which reduces acetate to acetaldehyde. Such an unfavourable reaction has often been considered unsuitable for a biological process. To answer this riddle, we demonstrated that the thermodynamic pull of CO-oxidation and ethanol synthesis is crucial for triggering acetate reduction. The experimental setup performed with native CO-dehydrogenase and AFOR highlighted the key role of ferredoxin in stimulating the activity of both metalloenzymes and electron shuttling. The crystal structure of holo AFOR refined to 1.59-[A] resolution, together with its biochemical characterisation, provides new insights into the reaction mechanism and the specificities of this enzyme fundamental to sustainable biofuel production.

biochemistry↗

bioRxiv2024

Recruitment of CTCF to the SIRT1 promoter after Oxidative Stress mediates Cardioprotective Transcription

Because most DNA-binding transcription factors (dbTFs), including the architectural regulator CTCF, bind RNA and exhibit di-/multimerization, a central conundrum is whether these distinct properties are regulated post-transcriptionally to modulate transcriptional programs. Here, investigating stress-dependent activation of SIRT1, encoding an evolutionarily-conserved protein deacetylase, we show that induced phosphorylation of CTCF acts as a rheostat to permit CTCF occupancy of low-affinity promoter DNA sites to precisely the levels necessary. This CTCF recruitment to the SIRT1 promoter is eliciting a cardioprotective cardiomyocyte transcriptional activation program and provides resilience against the stress of the beating heart in vivo. Mice harboring a mutation in the conserved low-affinity CTCF promoter binding site exhibit an altered, cardiomyocyte-specific transcriptional program and a systolic heart failure phenotype. This transcriptional role for CTCF reveals that a covalent dbTF modification regulating signal-dependent transcription serves as a previously unsuspected component of the oxidative stress response.

cell biology↗

bioRxiv2024

A high-throughput and sensitive method for food preference assays in walking insects

Insects pose significant challenges in both pest management and ecological conservation. Often, the most effective strategy is employing toxicant-laced baits, which must also be designed to specifically attract and be preferred by the targeted species for optimal species- specific effectiveness. However, traditional methods for measuring bait preference are either non-comparative, meaning that most animals only ever taste one bait, or suffer from methodological or conceptual limitations. Here we demonstrate the value of direct comparison food preference assays using the invasive and pest ant Linepithema humile (Mayr, 1868) as a model. We compare the food preference sensitivity of non-comparative (one visit to a food source) and sequential comparative (visiting one type of food then another) assays at detecting low levels of aversive quinine in sucrose solution. We then introduce and test a novel dual-choice feeder method for simultaneous comparative evaluation of bait preferences, testing its effectiveness in discerning between foods with varying quinine or sucrose levels. While the non-sequential assay could not detect aversion to 1.25mM quinine in 1M sucrose, the sequential comparative approach detected aversion to quinine levels as low as 0.94mM. The novel dual feeder method approach could detect aversion to quinine levels as low as 0.31mM, and also preference for 1M sucrose over 0.75M sucrose. The dual-feeder method combines the sensitivity of comparative evaluation with high throughput, ease of use, and avoidance of interpretational issues. This innovative approach offers a promising tool for rapid and effective testing of bait solutions, contributing to the development of targeted control strategies. The method could also be easily extended to other ant species.

animal behavior and cognition↗

bioRxiv2024

Butyrate and propionate are microbial danger signals that activate the NLRP3-inflammasome in human macrophages in the presence of TLR stimulation

Short chain fatty acids (SCFAs) are immunomodulatory compounds produced by the microbiome through fermentation of dietary fibre. Although they are generally considered beneficial for gut health, patients suffering from inflammatory bowel disease (IBD) have shown poor tolerance to fibre-rich diets, suggesting that SCFAs may have contrary effects under inflammatory conditions. To investigate this, we examined the effect of SCFAs on human macrophages in the presence of toll-like receptor agonists. In contrast to their anti-inflammatory effects under steady state conditions, we observed that the SCFAs butyrate and propionate triggered the activation of the NLRP3 inflammasome when added in conjunction with TLR agonists. Mechanistically, butyrate and propionate activated NLRP3 by inhibiting HDACs 1-3 and 10, leading to an uneven distribution of histone hyperacetylation that resulted in alterations in the transcriptome. Specifically, there was a lack of hyperacetylation at the loci of the CFLAR and IL10 genes, two important inhibitors of NLRP3 inflammasome activation. The concurrent loss of transcription and protein expression of cFLIP and IL-10 enabled caspase-8-dependent NLRP3-inflammasome activation. SCFA-driven NLRP3 activation did not require potassium efflux and did not result in cell death but rather triggered hyperactivation and IL-1{beta} release. Our findings demonstrate that butyrate and propionate are bacterially-derived, viability-dependent danger signals (vita-PAMPs) that regulate NLRP3 inflammasome activation through epigenetic modulation of the inflammatory response. SummaryUnder inflammatory conditions, SCFAs are bacterially-derived, viability-dependent danger signals that, through HDAC inhibition and epigenetic modification, prevent expression of the anti-cell death gene cFLIP to trigger activation of the NLRP3 inflammasome.

immunology↗

bioRxiv2024

F420 reduction as a cellular driver for anaerobic ethanotrophy

The anaerobic ethane oxidation performed by seafloor archaea and sulfate-reducing partner bacteria involves largely uncharted biochemistry. This study deciphers the molecular basis of the CO2-generating steps by characterizing the native archaeal enzymes isolated from a thermophilic enrichment culture. While other microorganisms couple these steps to ferredoxin reduction, we found that the CO-dehydrogenase and the formylmethanofuran-dehydrogenase are bound to an F420-reductase module. The crystal structures of these multi-metalloenzyme complexes revealed a [4Fe-4S]-cluster networks electronic bridges coupling C1-oxidation to F420-reduction. Accordingly, both systems exhibit robust F420-reductase activities, which are not detected in methanogenic or methanotrophic relative organisms. We speculate that the whole catabolism of these archaea is reoriented towards F420-reduction, which facilitates the electron transfer to the sulfate-reducing partner, therefore representing the driving force of ethanotrophy.

biochemistry↗

bioRxiv2023

Phytohormones regulate asexual Toxoplasma gondii

The protozoan Toxoplasma (T.) gondii is a zoonotic disease agent causing systemic infection in warm-blooded intermediate hosts including humans. During acute infections, the parasite infects host cells and multiplies intracellularly in the asexual tachyzoite stage. In this stage of the life cycle, invasion, multiplication, and egress are most critical events in the parasites replication. T. gondii features diverse cell organelles to support these processes, including the so-called apicoplast, an endosymbiont-derived vestigial plastid originating from an alga ancestor. Previous studies have highlighted that phytohormones can modify the calcium-mediated secretion, e.g., of adhesins involved in parasite movement and cell invasion processes. The present study aimed to elucidate the influence of different plant hormones on the replication of asexual tachyzoites in a human foreskin fibroblast (HFF) host cell culture. T. gondii replication was measured by the determination of T. gondii DNA copies via qPCR. Three selected phytohormones, namely abscisic acid (ABA), gibberellic acid (GIBB), and kinetin (KIN)as representatives of different plant hormone groups were tested. Moreover, the influence of typical cell culture media components on the phytohormone effects was assessed. Our results indicate that ABA is able to induce a significant increase of T. gondii DNA copies in typical supplemented cell culture medium when applied in concentrations of 20 ng/l or 2 ng/l, respectively. In contrast, depending on the culture medium composition, GIBB may potentially serve as T. gondii growth inhibitor and may be further investigated as a potential treatment for toxoplasmosis.

microbiology↗

bioRxiv2023

Can nestmate corpses cause bait neglect in invasive ants?

Invasive ants, such as Linepithema humile (the Argentine ant), pose a global threat, necessitating a better understanding of their behaviour in order to improve management strategies. Traditional eradication methods, including baiting, have had limited success, but the causes of control failure are not always clear. Here we propose that ants may learn to avoid toxic baits in part due to their association with ant corpses. Ants were tested on a Y-maze after exposure to scented corpses or dummies. 69% (n = 64) of ants avoided branches bearing the scent of scented corpses. At a collective level, colonies neglected food sources associated with scented ant corpses in favour of a food source with a novel odour, with only 42% (n = 273) of foragers feeding from the corpse-scent associated food source. However, if corpses were produced by feeding ants scented toxicant, focal ants encountering these corpses did not avoid the corpse-associated scent on a Y maze (53%, n = 65). Moreover, in a dual-feeder test, ants did not avoid feeding at food sources scented with an odour associated with conspecific corpses. The study demonstrates that conspecific corpses can act as a negative stimulus for Linepithema humile, leading to avoidance of odours associated with corpses, which can lead to potential avoidance of toxic baits. Why the more realistic Y-maze trial with corpses of ants that had ingested the toxicant elicited no avoidance is unclear: it may be due to weaker odour cues from ingested food, or a counterbalancing of the negative corpse stimulus by the positive presence of food remains on the corpse. Nonetheless, this study demonstrates that conspecific corpses act as a negative stimulus for ants, and this should be kept in mind when planning control efforts. A simple solution to this issue would be adding odours to baits, and cycling baits between treatments. This would disrupt the association between bait odour and corpses.

animal behavior and cognition↗