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bioRxiv2017

Heat Shock Protein 70 (Hsp70) Is Involved In The Zika Virus Cellular Infection Process

Zika virus (ZIKV) is a historically neglected flavivirus that has recently caused epidemics in the western hemisphere. ZIKV has been associated with severe symptoms including infant microcephaly and Guillain Barre syndrome, stimulating interest in understanding factors governing ZIKV infection. Heat shock protein 70 (Hsp70) has been shown to be an infection factor for multiple viruses. We investigated the role of Hsp70 in the ZIKV infection process. We localized Hsp70 protein to the Vero cell membrane surface by confocal microscopy and demonstrated that, inside the cell, there is significant co-localization between Hsp70 and ZIKV E protein. Inducing and suppressing Hsp70 expression increased and decreased ZIKV production, respectively. Antibody blocking cell surface-localized Hsp70 decreased ZIKV cell infection rates and production of infectious virus particles, as did competition with recombinant Hsp70 protein. Our data suggest that Hsp70 is an important factor in the ZIKV infection process. Understanding the interactions between Hsp70 and ZIKV may lead to novel therapeutics for ZIKV infection, particularly for pregnant women and fetuses.

microbiology↗

bioRxiv2017

Epha2, An Epithelial Cell Pattern Recognition Receptor For Fungal β-Glucans

AbstractOral epithelial cells discriminate between pathogenic and non-pathogenic stimuli, and only induce an inflammatory response when they are exposed to high levels of a potentially harmful microorganism. The pattern recognition receptors (PRRs) in epithelial cells that mediate this differential response are poorly understood. Here, we demonstrate that the ephrin type-A receptor 2 (EphA2) is an oral epithelial cell PRR that binds to exposed {beta}-glucans on the surface of the fungal pathogen Candida albicans. Binding of C. albicans to EphA2 on oral epithelial cells activates signal transducer and activator of transcription 3 (Stat3) and mitogen-activated protein kinase signaling in an inoculum-dependent manner, and is required for induction of a pro-inflammatory and antifungal response. Inhibition of EphA2 in mice decreases IL-17 signaling during oropharyngeal candidiasis, resulting in increased oral fungal burden and fungal dissemination. Our study reveals that EphA2 functions as PRR for {beta}-glucans that senses epithelial cell fungal burden and is required for the maximal mucosal inflammatory response to C. albicans.\n\nOne Sentence SummaryEphA2 is a pattern recognition receptor that senses fungal {beta}-glucans to induce an inflammatory response in oral epithelial cells.

microbiology↗

bioRxiv2017

African Nonhuman Primates Are Infected With The Yaws Bacterium Treponema pallidum subsp. pertenue

Treponema pallidum subsp. pertenue (TPE) is the causative agent of yaws. The disease was subject to global eradication efforts in the mid 20th century but reemerged in West Africa, Southern Asia, and the Pacific region. Despite its importance for eradication, detailed data on possible nonhuman disease reservoirs are missing. A number of African nonhuman primates (NHPs) have been reported to show skin ulcerations suggestive of treponemal infection in humans. Furthermore antibodies against Treponema pallidum (TP) have been repeatedly detected in wild NHP populations. While genetic studies confirmed that NHPs are infected with TP strains, subspecies identification was only possible once for a strain isolated in 1966, pinpointing the involvement of TPE. We therefore collected a number of recently isolated simian TP strains and determined eight whole genome sequences using hybridization capture or long-range PCR combined with next-generation sequencing. These new genomes were compared with those of known human TP isolates. Our results show that naturally occurring simian TP strains circulating in three African NHP species all cluster with human TPE strains and show the same genomic structure as human TPE strains. These data indicate that humans are not the exclusive host for the yaws bacterium and that a One Health approach is required to achieve sustainable eradication of human yaws.

microbiology↗

bioRxiv2017

KKL-35 Exhibits Potent Antibiotic Activity Against Legionella Species Independently Of Trans-Translation Inhibition

Trans-translation is a ribosome rescue system that is ubiquitous in bacteria. Small molecules defining a new family of oxadiazole compounds that inhibit trans-translation have been found to have broad-spectrum antibiotic activity. We sought to determine the activity of KKL-35, a potent member of the oxadiazole family, against the human pathogen Legionella pneumophila and other related species that can also cause Legionnaires disease (LD). Consistent with the essential nature of trans-translation in L. pneumophila, KKL-35 inhibits growth of all tested strains at sub-micromolar concentrations. KKL-35 is also active against other LD-causing Legionella species. KKL-35 remains equally active against L. pneumophila mutants that have evolved resistance to macrolides. KKL-35 inhibits multiplication of L. pneumophila in human macrophages at several stages of infection. No resistant mutants could be obtained, even during extended and chronic exposure. Surprisingly, KKL-35 is not synergistic with other ribosome-targeting antibiotics and does not induce the filamentation phenotype observed in cells defective for trans-translation. Importantly, KKL-35 remains active against L. pneumophila mutants expressing an alternate ribosome-rescue system and lacking tmRNA, the essential component of trans-translation. These results indicate that the antibiotic activity of KKL-35 is not related to the specific inhibition of trans-translation and its mode of action remains to be identified. In conclusion, KKL-35 is an effective antibacterial agent against the intracellular pathogen L. pneumophila and with no detectable resistance. However, further studies are needed to better understand its mechanism of action and to assess further the potential of oxadiazoles in treatment.

microbiology↗

bioRxiv2017

Wolbachia Effects On Rift Valley Fever Virus Infection In Culex tarsalis Mosquitoes

Innovative tools are needed to alleviate the burden of mosquito-borne diseases, and strategies that target the pathogen instead of the mosquito are being considered. A possible tactic is the use of Wolbachia, a maternally inherited, endosymbiotic bacterium that can suppress diverse pathogens when introduced to naive mosquito species. We investigated effects of somatic Wolbachia (strain wAlbB) infection on Rift Valley fever virus (RVFV) in Culex tarsalis mosquitoes. When compared to Wolbachia-uninfected mosquitoes, there was no significant effect of Wolbachia infection on RVFV infection, dissemination, or transmission frequencies, nor on viral body or saliva titers. Within Wolbachia-infected mosquitoes, there was a modest negative correlation between RVFV body titers and Wolbachia density, suggesting that Wolbachia may suppress RVFV in a density-dependent manner in this mosquito species. These results are contrary to previous work in the same mosquito species, showing Wolbachia-induced enhancement of West Nile virus infection rates. Taken together, these results highlight the importance of exploring the breadth of phenotypes induced by Wolbachia.\n\nAuthor SummaryAn integrated vector management program utilizes several practices, including pesticide application and source reduction, to reduce mosquito populations. However, mosquitoes are developing resistance to some of these methods and new control approaches are needed. A novel technique involves the bacterium Wolbachia that lives naturally in many insects. Wolbachia can be transferred to uninfected mosquitoes and can block pathogen transmission to humans. Additionally, Wolbachia is maternally inherited, allowing it to spread quickly through uninfected field populations of mosquitoes. We studied the impacts of Wolbachia on Rift Valley fever virus (RVFV) in the naturally uninfected mosquito, Culex tarsalis. Wolbachia had no effects on the ability of Culex tarsalis to become infected with or transmit RVFV. High densities of Wolbachia were associated with no virus infection or low levels of virus, suggesting that Wolbachia might suppress RVFV at high densities. These results contrast with our previous study that showed Wolbachia enhances West Nile virus infection in Culex tarsalis. Together, these studies highlight the importance of studying Wolbachia effects on a variety of pathogens so that control methods are not impeded.

microbiology↗

bioRxiv2017

The dental calculus metabolome in modern and historic samples

IntroductionDental calculus is a mineralized microbial dental plaque biofilm that forms throughout life by precipitation of salivary calcium salts. Successive cycles of dental plaque growth and calcification make it an unusually well-preserved, long-term record of host-microbial interaction in the archaeological record. Recent studies have confirmed the survival of authentic ancient DNA and proteins within historic and prehistoric dental calculus, making it a promising substrate for investigating oral microbiome evolution via direct measurement and comparison of modern and ancient specimens.\n\nObjectiveWe present the first comprehensive characterization of the human dental calculus metabolome using a multi-platform approach.\n\nMethodsUltra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) quantified 285 metabolites in modern and historic (200 years old) dental calculus, including metabolites of drug and dietary origin. A subset of historic samples was additionally analyzed by high-resolution gas chromatography-MS (GC-MS) and UPLC- MS/MS for further characterization of polar metabolites and lipids, respectively. Metabolite profiles of modern and historic calculus were compared to identify patterns of persistence and loss.\n\nResultsDipeptides, free amino acids, free nucleotides, and carbohydrates substantially decrease in abundance and ubiquity in archaeological samples, with some exceptions. Lipids generally persist, and saturated and mono-unsaturated medium and long chain fatty acids appear to be well-preserved, while metabolic derivatives related to oxidation and chemical degradation are found at higher levels in archaeological dental calculus than fresh samples.\n\nConclusionsThe results of this study indicate that certain metabolite classes have higher potential for recovery over long time scales and may serve as appropriate targets for oral microbiome evolutionary studies.

microbiology↗

bioRxiv2017

Diversity Of Biocrust-Forming Cyanobacteria In A Semiarid Gypsiferous Site From Central Spain

Cyanobacteria are an important constituent of biocrusts, communities dominated by lichens, mosses and associated microorganisms, which are prevalent in drylands worldwide and that largely determine their functioning. Despite their importance, there are large gaps in our knowledge of cyanobacteria associated to biocrusts, particularly in areas such as the Mediterranean Basin. We studied the diversity of these cyanobacteria in a gypsiferous grassland from Central Spain using both morphological identification after cultivation and genetic analyses with the 16S rRNA gene. Eight different morphotypes were observed, most of them corresponding to filamentous and one of them to unicellular cyanobacteria. We found cyanobacterial genera typical of biocrust communities, such as Microcoleus, Schizothrix or Tolypothrix, and N-fixing cyanobacteria as Scytonema or Nostoc. Genetic information allowed us to identify cultures belonging to recently described genera such as Roholtiella, Nodosilinea and Mojavia. In this study we describe two new phylotypes of Microcoleus and Scytonema, which are key genera contributing to ecosystem functioning in biocrust-dominated ecosystems worldwide.

microbiology↗

bioRxiv2017

Adaptation Of Staphylococcus saprophyticus At The Host-Pathogen Interface

Human-pathogenic bacteria are found in a variety of niches, including free-living, zoonotic, and microbiome environments. Identifying bacterial adaptions that enable invasive disease is an important means of gaining insight into the molecular basis of pathogenesis and understanding pathogen emergence. Staphylococcus saprophyticus, a leading cause of urinary tract infections, can be found in the environment, food, animals, and the human microbiome. We identified a selective sweep in the gene encoding the Aas adhesin, a key virulence factor that binds host fibronectin. We hypothesize that the mutation under selection (aas_2206A>C) facilitates colonization of the urinary tract, an environment where bacteria are subject to strong shearing forces. The mutation appears to have enabled emergence and expansion of a human pathogenic lineage of S. saprophyticus. These results demonstrate the power of evolutionary genomic approaches in discovering the genetic basis of virulence and emphasize the pleiotropy and adaptability of bacteria occupying diverse niches.\n\nImportanceStaphylococcus saprophyticus is an important cause of urinary tract infections (UTI) in women, which are common, can be severe, and are associated with significant impacts to public health. In addition to being a cause of human UTI, S. saprophyticus can be found in the environment, in food, and associated with animals. After discovering that UTI strains of S. saprophyticus are for the most part closely related to each other, we sought to determine whether these strains are specially adapted to cause disease in humans. We found evidence suggesting that a mutation in the gene aas is advantageous in the context of human infection. We hypothesize that the mutation allows S. saprophyticus to survive better in the human urinary tract. These results show how bacteria found in the environment can evolve to cause disease.

microbiology↗

bioRxiv2017

FplA From Fusobacterium nucleatum Is A Type Vd Autotransporter Phospholipase With A Proposed Role In Altered Host Signaling And Evasion Of Autophagy

Fusobacterium nucleatum is a pathogenic oral bacterium that is linked to multiple human infections and colorectal cancer. While most Gram-negative pathogens utilize secretion systems for cellular invasion and infection, F. nucleatum lacks Type I, II, III, IV, and VI secretion. By contrast, F. nucleatum strains are enriched in Type V secreted autotransporters, which are Gram-negative bacterial virulence factors critical for binding and entry into host cells. Here we present the first biochemical characterization of a F. nucleatum Type Vd phospholipase class A1 autotransporter (strain ATCC 25586, gene FN1704) that we hereby rename Fusobacterium phospholipase autotransporter (FplA). FplA is expressed as a full-length 85 kDa outer membrane embedded protein, or as a truncated phospholipase domain that remains associated with the outer membrane. Using multiple FplA constructs we characterized lipid substrate specificity, potent inhibitors, and chemical probes to detect and track this enzyme family. While the role of FplA is undetermined in F. nucleatum virulence, homologous phospholipases from intracellular pathogens are critical for vacuole escape, altered host signaling, and intracellular survival. We hypothesize that upon intracellular invasion of the host, FplA could play a role in phagosomal escape, subversion of autophagy, or eicosanoid-mediated inflammatory signaling, as we show that FplA binds with high affinity to host phosphoinositide signaling lipids critical to these processes. Our identification of substrates, inhibitors, and chemical probes for FplA, in combination with an fplA gene deletion strain, encompass a powerful set of tools for the future analysis of FplA in vivo. In addition, these studies will guide the biochemical characterization of additional Type Vd autotransporter phospholipases.\n\nIMPORTANCEF. nucleatum is an emerging pathogen that is linked to the pathogenesis of colorectal cancer, yet there is a critical knowledge gap in the mechanisms used by this bacterium to elicit changes in the host for intracellular entry and survival. As phospholipases are critical virulence factors for intracellular bacteria to initiate vacuole lysis, cell-to-cell spread, and evasion of autophagy, we set out to characterize a unique Type Vd secreted phospholipase A1 enzyme from F. nucleatum. Our results show a potential role for modulating host signaling pathways through cleavage of phosphoinositide dependent signaling lipids. These studies open the door for further characterization of this unique enzyme family in bacterial virulence, host-pathogen interactions, and for F. nucleatum, in colorectal carcinogenesis.

microbiology↗

bioRxiv2017

Global Phylogenetic Analysis Of Escherichia coli And Plasmids Carrying The mcr-1 Gene Indicates Bacterial Diversity But Plasmid Restriction

To understand the dynamics behind the worldwide spread of the mcr-1 gene, we determined the population structure of Escherichia coli and of mobile genetic elements (MGEs) carrying the mcr-1 gene. After a systematic review of the literature we included 65 E. coli whole genome sequences (WGS), adding 6 recently sequenced travel related isolates, and 312 MLST profiles. We included 219 MGEs described in 7 Enterobacteriaceae species isolated from human, animal and environmental samples. Despite a high overall diversity, 2 lineages were observed in the E. coli population that may function as reservoirs of the mcr-1 gene, the largest of which was linked to ST10, a sequence type known for its ubiquity in human faecal samples and in food samples. No genotypic clustering by geographical origin or isolation source was observed. Amongst a total of 13 plasmid incompatibility types, the Incl2, lncX4 and IncHI2 plasmids accounted for more than 90% of MGEs carrying the mcr-1 gene. We observed significant geographical clustering with regional spread of lncHI2 plasmids in Europe and Incl2 in Asia. These findings point towards promiscuous spread of the mcr-1 gene by efficient horizontal gene transfer dominated by a limited number of plasmid incompatibility types.

microbiology↗

bioRxiv2017

Modifying And Reacting To The Environmental pH Drives Bacterial Interactions

Microbes usually exist in communities consisting of myriad different but interacting species. These interactions are typically mediated through environmental modifications; microbes change the environment by taking up resources and excreting metabolites, which affects the growth of both themselves and also other microbes. A very common environmental modification is a change of the environmental pH. Here we show that changing and reacting to the pH leads to a feedback loop that can determine the fate of bacterial populations. We find experimentally that these pH changes can decide the fate of bacterial populations; they can either facilitate or inhibit growth, and in extreme cases will cause extinction of the bacterial population. Moreover, modifying the pH can determine the interactions between different species. Understanding how single species change the pH and react to it allowed us to estimate their pairwise interaction outcomes. Those interactions lead to a set of generic interaction motifs--bistability, succession, murder suicide, and mutualism--that may be independent of which environmental parameter is modified and thus reoccur in different microbial systems.

microbiology↗

bioRxiv2017

Systematic Genetic Dissection Of Chitin Degradation And Uptake In Vibrio cholerae

Vibrio cholerae is a natural resident of the aquatic environment, where a common nutrient is the chitinous exoskeletons of microscopic crustaceans. Chitin utilization requires chitinases, which degrade this insoluble polymer into soluble chitin oligosaccharides. These oligosaccharides also serve as an inducing cue for natural transformation in Vibrio species. There are 7 predicted endochitinase-like genes in the V. cholerae genome. Here, we systematically dissect the contribution of each gene to growth on chitin as well as induction of natural transformation. Specifically, we created a strain that lacks all 7 putative chitinases and from this strain, generated a panel of strains where each expresses a single chitinase. We also generated expression plasmids to ectopically express all 7 chitinases in our chitinase deficient strain. Through this analysis, we found that low levels of chitinase activity are sufficient for natural transformation, while growth on insoluble chitin as a sole carbon source requires more robust and concerted chitinase activity. We also assessed the role that the three uptake systems for the chitin degradation products GlcNAc, (GlcNAc)2, and (GlcN)2, play in chitin utilization and competence induction. Cumulatively, this study provides mechanistic details for how this pathogen utilizes chitin to thrive and evolve in its environmental reservoir.\n\nORIGINALITY-SIGNIFICANCE STATEMENTVibrio cholerae, the causative agent of the diarrheal disease cholera, interacts with the chitinous shells of crustacean zooplankton in the aquatic environment, which serves as an environmental reservoir for this pathogen. It degrades and utilizes chitin-derived products as a source of carbon and nitrogen. Also, chitin serves as an inducing cue for natural transformation - an important mechanism of horizontal gene transfer in this species. Here, we systematically dissect the genes required for chitin degradation and uptake, and characterize the role of these genes for growth on chitin as a nutrient and during chitininduced natural transformation. Thus, this study provides mechanistic details for how this pathogen utilizes chitin to thrive and evolve in its environmental reservoir.

microbiology↗

bioRxiv2017

Priming In A Permissive Type I-C CRISPR-Cas System Reveals Distinct Dynamics Of Spacer Acquisition And Loss

CRISPR-Cas is a bacterial and archaeal adaptive immune system that uses short, invader-derived sequences termed spacers to target invasive nucleic acids. Upon recognition of previously encountered invaders, the system can stimulate secondary spacer acquisitions, a process known as primed adaptation. Previous studies of primed adaptation have been complicated by intrinsically high interference efficiency of most systems against bona fide targets. As such, most primed adaptation to date has been studied within the context of imperfect sequence complementarity between spacers and targets. Here, we take advantage of a native type I-C CRISPR-Cas system in Legionella pneumophila that displays robust primed adaptation even within the context of a perfectly matched target. Using next-generation sequencing to survey acquired spacers, we observe strand bias and positional preference that are consistent with a 3' to 5' translocation of the adaptation machinery. We show that spacer acquisition happens in a wide range of frequencies across the plasmid, including a remarkable hotspot that predominates irrespective of the priming strand. We systematically characterize protospacer sequence constraints in both adaptation and interference and reveal extensive flexibilities regarding the protospacer adjacent motif in both processes. Lastly, in a strain with a genetically truncated CRISPR array, we observe greatly increased interference efficiency coupled with a dramatic shift away from spacer acquisition towards spacer loss. Based on these observations, we propose that the Legionella type I-C system represents a powerful model to study primed adaptation and the interplay between CRISPR interference and adaptation.

microbiology↗

bioRxiv2017

The CRISPR Spacer Space Is Dominated By Sequences From The Species-Specific Mobilome

The CRISPR-Cas is the prokaryotic adaptive immunity system that stores memory of past encounters with foreign DNA in spacers that are inserted between direct repeats in CRISPR arrays 1,2. Only for a small fraction of the spacers, homologous sequences, termed protospacers, are detectable in viral, plasmid or microbial genomes 3,4. The rest of the spacers remain the CRISPR \"dark matter\". We performed a comprehensive analysis of the spacers from all CRISPR-cas loci identified in bacterial and archaeal genomes, and found that, depending on the CRISPR-Cas subtype and the prokaryotic phylum, protospacers were detectable for 1 to about 19% of the spacers ([~]7% global average). Among the detected protospacers, the majority, typically, 80 to 90%, originate from viral genomes, and among the rest, the most common source are genes integrated in microbial chromosomes but involved in plasmid conjugation or replication. Thus, almost all spacers with identifiable protospacers target mobile genetic elements (MGE). The GC-content, as well as dinucleotide and tetranucleotide compositions, of microbial genomes, their spacer complements, and the cognate viral genomes show a nearly perfect correlation and are almost identical. Given the near absence of self-targeting spacers, these findings are best compatible with the possibility that the spacers, including the dark matter, are derived almost completely from the species-specific microbial mobilomes.

microbiology↗

bioRxiv2017

A Tunable Protein Oscillator Controls Directional Movements In Myxococcus xanthus

Dynamic control of cell polarity is of critical importance for many aspects of cellular development and motility. In Myxococcus xanthus, a G-protein and its cognate GTPase-activating protein establish a polarity axis that defines the direction of movement of the cell and which can be rapidly inverted by the Frz chemosensory system. Although vital for collective cell behaviours, how Frz triggers this switch has remained unknown. Here, we use genetics, imaging and mathematical modelling to show that Frz controls polarity reversals via a gated relaxation oscillator. FrzX, which we newly identify as the primary Frz output, provides the gating and thus acts as the trigger for reversals. Slow relocalisation of the polarity protein RomR then creates a refractory period during which another switch cannot be triggered. A secondary Frz output, FrzZ, decreases this delay allowing rapid reversals when required. This architecture thus results in a highly tunable switch that allows a wide range of motility responses.

microbiology↗

bioRxiv2017

Uncovering The Drivers Of Animal-Host Microbiotas With Joint Distribution Modeling

In addition to the processes structuring free-living communities, host-associated microbiota are directly or indirectly shaped by the host. Therefore, microbiota data have a hierarchical structure where samples are nested under one or several variables representing host-specific factors, often spanning multiple levels of biological organization. Current statistical methods do not accommodate this hierarchical data structure, and therefore cannot explicitly account for the effect of the host in structuring the microbiota. We introduce a novel extension of joint species distribution models which can straightforwardly accommodate and discern between effects such as host phylogeny and traits, recorded covariates like diet and collection site, among other ecological processes. Our proposed methodology includes powerful yet familiar outputs seen in community ecology overall, including: (i) model-based ordination to visualize and quantify the main patterns in the data; (ii) variance partitioning to asses how influential the included host-specific factors are in structuring the microbiota; and (iii) co-occurrence networks to visualize microbe-to-microbe associations.

microbiology↗

bioRxiv2017

Yeasts Dominate Soil Fungal Communities In Three Lowland Neotropical Rainforests

Forest soils typically harbour a vast diversity of fungi, but are usually dominated by filamentous (hyphae-forming) taxa. Compared to temperate and boreal forests, though, we have limited knowledge about the fungal diversity in tropical rainforest soils. Here we show, by environmental metabarcoding of soil samples collected in three Neotropical rainforests, that Yeasts dominate the fungal communities in terms of the number of sequencing reads and OTUs. These unicellular forms are commonly found in aquatic environments, and their hyperdiversity may be the result of frequent inundation combined with numerous aquatic microenvironments in these rainforests. Other fungi that are frequent in aquatic environments, such as the abundant Chytridiomycotina, were also detected. While there was low similarity in OTU composition within and between the three rainforests, the fungal communities in Central America were more similar to each other than the communities in South America, reflecting a general biogeographic pattern also seen in animals, plants, and protists.\n\nContactdunthorn@rhrk.uni-kl.de

microbiology↗

bioRxiv2017

Bifunctionality Of A Biofilm Matrix Protein Controlled By Redox State

Biofilms are communities of microbial cells that are encapsulated within a self-produced polymeric matrix. The matrix is critical to the success of biofilms in diverse habitats, but despite this many details of the composition, structure, and function remain enigmatic. Biofilms formed by the Gram-positive bacterium Bacillus subtilis depend on the production of the secreted film-forming protein BslA. Here we show that a gradient of electron acceptor availability through the depth of the biofilm gives rise to two distinct functional roles for BslA and that these can be genetically separated through targeted amino acid substitutions. We establish that monomeric BslA is necessary and sufficient to give rise to complex biofilm architecture, while dimerization of BslA is required to render the community hydrophobic. Dimerization of BslA, mediated by disulfide bond formation, depends on two conserved cysteine residues located in the C-terminal region. Our findings demonstrate that bacteria have evolved multiple uses for limited elements in the matrix, allowing for alternative responses in a complex, changing environment.\n\nSignificanceThe biofilm matrix is a critical target in the hunt for novel strategies to destabilise or stabilise biofilms. Knowledge of the processes controlling matrix assembly is therefore an essential prerequisite to exploitation. Here we highlight that the complexity of the biofilm matrix is even higher than anticipated with one matrix component making two independent functional contributions to the community. The influence the protein exerts is dependent on the local environmental properties, providing another dimension to consider during analysis. These findings add to the evidence that bacteria can evolve multifunctional uses for the extracellular matrix components.

microbiology↗