In this study, we examined the effects of antibiotic-mediated DNA damage on vesiculation in a clinical strain of Stenotrophomonas maltophilia (strain 44/98, also referred to as LMG 26284). Although genomic analysis of this strain revealed multiple prophage clusters, subsequent proteomic analysis showed that, among the proteins most significantly affected by ciprofloxacin exposure, the majority belonged to the previously described maltocin gene cluster. We showed that deletion of the gene coding for the maltocin endolysin (mal) reduces cell lysis and, in turn, the vesiculation capacity of S. maltophilia. Furthermore, using a combination of fluorescence and cryogenic electron microscopy, we provided evidence that the spontaneous re-arrangement of shattered membrane fragments attributable to mal-induced explosive cell lysis results in the formation of predominantly single-layered explosive outer membrane vesicles, while only a minor portion are double-layered outer-inner membrane vesicles. We also detected putative cytoplasmic vesicles in these samples, suggesting an expanded role of cell lysis in vesicle formation. Finally, we showed that the maltocin endolysin (LysSM) is upregulated rapidly in response to DNA damage stress and accumulates at the cell poles, which are likely the sites of subsequent cell lysis. Our findings expand on the involvement of (cryptic) tailocins in vesicle biogenesis under stress conditions.IMPORTANCEIn their natural environment, bacterial cells are able to communicate among themselves in multiple ways, and this communication has important implications for their ability to deal with unfavorable conditions. One key consequence is the spread of antimicrobial resistance from resistant cells to the remaining population, and such transfer can be mediated by membrane vesicles. In the highly multidrug-resistant bacterium Stenotrophomonas maltophilia, there exists a prophage that produces an endolysin capable of causing cell lysis and atypical vesicle production. The significance of this study lies in the description of such less characterized types of membrane vesicles produced in response to DNA damage, thereby providing insight into how bacteria respond to stress that can be brought about by antibiotic exposure.

This study maps the surfaceome of Apis mellifera hemocytes, the protagonist cells in honey bee cellular immunity. The surfaceome, proteins expressed at the cell surface, is crucial as it determines how cells interact with their microenvironment. Through a combination of proteomic and transcriptomic analyses, 1142 genes encoding cell surface proteins were identified, revealing a high level of diversity. Our analyses identified receptors associated with the major insect immune pathways and proteins previously recognized as hemocyte markers in other invertebrates. Notably, several of the detected genes suggest to encode viral receptors, phagocytosis-related proteins, or proteins involved in hemocyte proliferation. A gene ontology analysis highlighted important functions of the hemocytes. The most prominent cluster was transmembrane receptor protein kinase activity, encompassing over 25 % of the identified terms. Other significant clusters included cell adhesion molecule binding, signalling receptor binding, olfactory receptor activity, and metalloendopeptidase activity. This study suggests several potential honey bee hemocyte markers and establishes a foundation for a novel hemocyte classification based on cell surface markers.

The use of fluorescent proteins to study protein expression and localisation has become common practice in the life sciences. While methods to create gene fusions and replacements with fluorescent proteins in model organisms have rapidly developed, there exist far fewer well-established protocols applicable to non-model bacteria. Here, we present a comprehensive account of an allelic-exchange-based mutagenesis strategy using the I-SceI endonuclease in a clinical strain of S. maltophilia. We demonstrate the use of this strategy for the creation of in-frame insertions of fluorescent proteins and entire gene replacements for the purposes of studying protein localisation and expression. This protocol requires minimal setup, and once optimised, can produce mutants in a matter of weeks. We expect this strategy to be of use for laboratories working with poorly-characterised strains and/or bacteria for which information is scarce.

Like other Gram-negative bacteria, S. maltophilia is capable of producing membrane vesicles under normal growth conditions. The addition of certain exogenous triggers stimulates the production of vesicles, including those that are distinct from the archetypal outer membrane vesicle. In this study, we examine the effects of DNA damage on vesiculation, with a focus on the role of a bacteriophage-encoded endolysin. We demonstrate that deletion of the gene that encodes this protein (mal) negatively affects the vesiculation capacity of S. maltophilia. Further, we provide evidence that the spontaneous re-arrangement of shattered membrane fragments attributable to mal-induced explosive cell lysis results in the formation of predominantly explosive outer membrane vesicles, while only a minor portion are outer-inner membrane vesicles. Our findings expand on the current knowledge of (cryptic) tailocins in the biogenesis of vesicles in conditions of stress. ### Competing Interest Statement The authors have declared no competing interest.

BACKGROUND:Sophorolipids (SLs) are a class of natural, biodegradable surfactants that found their way as ingredients for environment friendly cleaning products, cosmetics and nanotechnological applications. Large-scale production relies on fermentations using the yeast Starmerella bombicola that naturally produces high titers of SLs from renewable resources. The resulting product is typically an extracellular mixture of acidic and lactonic congeners. Previously, we identified an esterase, termed Starmerella bombicola lactone esterase (SBLE), believed to act as an extracellular reverse lactonase to directly use acidic SLs as substrate. RESULTS:We here show based on newly available pure substrates, HPLC and mass spectrometric analysis, that the actual substrates of SBLE are in fact bola SLs, revealing that SBLE actually catalyzes an intramolecular transesterification reaction. Bola SLs contain a second sophorose attached to the fatty acyl group that acts as a leaving group during lactonization. CONCLUSIONS:The biosynthetic function by which the Starmerella bombicola 'lactone esterase' converts acidic SLs into lactonic SLs should be revised to a 'transesterase' where bola SL are the true intermediate. This insights paves the way for alternative engineering strategies to develop designer surfactants.

Over the past decade, silk sericin has emerged as a promising material for biomedical applications, especially in tissue engineering, where fine-tuning the physicochemical properties is crucial. However, previous studies, including those on the methacrylation of sericin (yielding SS-MA), showed limited tunability. Here, we developed a photo-cross-linkable sericin-based material modified with 2-aminoethyl methacrylate (AEMA) using two synthesis routes: sequential modification of SS-MA with AEMA (SS-MA-AEMA) and an efficient one-pot synthesis (SS-AEMA). The one-pot synthesis yielded materials containing only methacrylate groups, unlike the sequential modification that yielded a combination of methacrylamides and methacrylates. Our approach resulted in superior physicochemical properties. The resulting materials, including the previously described SS-MA, exhibited a broad range of properties, such as cross-linking kinetics (0.9-64.0 s), swelling behavior (311-3775%), and mechanical properties (10-140 kPa). These properties support applications across various tissues, from dermis to fibrous tissue. The materials also demonstrated fibroblast cytocompatibility with cell viabilities exceeding 96%.

Candida albicans is an emerging pathogen that poses a significant challenge due to its multidrug-resistant nature. There are two types of antifungal agents, fungicidal and fungistatic, with distinct mechanisms of action against fungal pathogens. Fungicidal agents kill fungal pathogens, whereas fungistatic agents inhibit their growth. The growth can be restored once the agent is removed and favorable conditions are established. Recognizing this difference is crucial as it influences treatment selection and infection prognosis. We present a technique based on optical nanomotion detection (ONMD) (i.e., observing the movement of the cells using an optical microscope) to discriminate rapidly between fungicidal (caspofungin) and fungistatic (fluconazole) drugs. The technique is based on the change in a yeast cell’s nanomotion as a function of time during a two-hour treatment with the antifungal of interest followed by a one-hour growth period. The cells are entrapped in microwells in a microfluidic chip, which allows a quick exchange of growth medium and antifungal agent, enabling ONMD measurements on the same individual cells before and after treatment. This procedure permits to discriminate between fungicidal and fungistatic antifungals in less than 3 h, with single-cell resolution by observing if the nanomotion recovers after removing the treatment and reintroducing growth medium (YPD), or continues to drop. The simplicity of the approach holds promise for further development into a user-friendly device for rapid antifungal susceptibility testing (AFST), potentially being implemented in hospitals and medical centers worldwide in developed and developing countries.

Traditional medicinal plants represent a unique source for the isolation of Streptomycetes and antimicrobial compounds. Antimicrobial activity of Streptomyces isolates collected from the rhizosphere of different native medicinal plants in Iran, was investigated against Gram-positive and Gram-negative bacteria. Multi-omics analysis was performed to identify active compounds corresponding to the observed bioactivities. Since cell-to-cell communication mediated by N-acyl homoserine lactones (AHLs) is important for the virulence of Gram-negative pathogenic bacteria, quorum quenching activity of the isolates and their ability to degrade C6-HSL and C8-HSL were tested. Two highly related Streptomyces isolates derived from the Helichrysum rubicundum and Rumex acetosa rhizosphere, respectively, exhibited bioactivity against pathogenic indicator bacteria. Metabolite analysis of extracts obtained from liquid cultures of both isolates revealed the production of the catechol-peptide siderophores streptobactin and tribenarthin. Proteomic analysis confirmed the presence of proteins encoded by the streptobactin and lidamycin biosynthetic gene clusters. Quorum quenching activity of the strains and AHL-degrading enzyme production was confirmed using a GFP producing biosensor and LC-MS analysis. This study demonstrates catecholate siderophore production and QQ potential of two Streptomyces isolates from medicinal plants rhizosphere from Mishan Plain, Hamedan Province, Iran using metabolomics and proteomics analysis. Production of streptobactin by terrestrial Streptomyces sp. strains was confirmed for the first time.

The yeast Starmerella bombicola is renowned for its highly efficient sophorolipid production, reaching titers and productivities of (over) 200 g/L and 2 g/(L h), respectively. This inherent efficiency has led to the commercialization of sophorolipids. While the sophorolipid biosynthetic pathway has been elucidated a few years ago, in this study, it is revisited and true key intermediates are revealed. Recently, Starmerella bombicola strains developed and evaluated in the past were reevaluated unveiling unexpected findings. The AT enzyme encoded in the sophorolipid biosynthetic gene cluster is the only described enzyme known to acetylate sophorolipids, while the SBLE enzyme encoded by the SBLE gene is described to catalyze the conversion of (acetylated) acidic sophorolipids into lactonic sophorolipids. A double knockout of both genes was described to result in the generation of bolaform sophorolipids. However, new experiments performed with respective S. bombicola strains Δsble, Δat Δsble, and ∆at revealed inconsistencies with the current understanding of the SL pathway. It was observed that the ∆sble strain produces mainly bolaform sophorolipids with higher acetylation degrees instead of acidic sophorolipids. Furthermore, the ∆at strain produces predominantly bolaform sophorolipids and lactonic sophorolipids with lower acetylation degrees, while the ∆at ∆sble strain predominantly produces bolaform sophorolipids with lower acetylation degrees. These results indicate that the AT enzyme is not the only enzyme responsible for acetylation of sophorolipids, while the SBLE enzyme performs an intramolecular transesterification reaction on bolaform glycolipids instead of an esterification reaction on acidic sophorolipids. These findings, together with recent in vitro data, led us to revise the sophorolipid biosynthetic pathway. Bolaform sophorolipids instead of acidic sophorolipids are the key intermediates in the biosynthetic pathway towards lactonic sophorolipids. Bolaform sophorolipids are found in very small amounts in extracellular S. bombicola wild type broths as they are very efficiently converted into lactonic sophorolipids, while acidic sophorolipids build up as they cannot be converted. Furthermore, acetylation of sophorolipids is not exclusively performed by the AT enzyme encoded in the sophorolipid biosynthetic gene cluster and acetylation of bolaform sophorolipids promotes their transesterification. These findings led to the revision of the industrially relevant sophorolipid biosynthetic pathway.

Carlsberg subtilisin from Bacillus licheniformis PB1 was investigated as a potential feed supplement, through immobilizing on bentonite for improving the growth rate of broilers. Initially, the pre-optimized and partially-purified protease was extracted and characterized using SDS-PAGE with MW 27.0 KDa. The MALDI-TOF-MS/MS spectrum confirmed a tryptic peptide peak with m/z 1108.496 referring to the Carlsberg subtilisin as a protein-digesting enzyme with alkaline nature. The highest free enzyme activity (30 U/mg) was observed at 50°C, 1 M potassium phosphate, and pH 8.0. the enhanced stability was observed when the enzyme was adsorbed to an inert solid support with 86.39 ± 4.36% activity retention under 20 optimized conditions. Additionally, the dried immobilized enzyme exhibited only a 5% activity loss after two-week storage at room temperature. Structural modeling (Docking) revealed that hydrophobic interactions between bentonite and amino acids surrounding the catalytic triad keep the enzyme structure intact upon drying at RT. The prominent hygroscopic nature of bentonite facilitated protein structure retention upon drying. During a 46-days study, supplementation of boilers’ feed with the subtilisin–bentonite complex promoted significant weight gain i.e. 15.03% in contrast to positive control (p = 0.001).

Background and aim: The nematodes Anisakis simplex and Pseudoterranova decipiens, are zoonotic parasites infecting many marine fish and pose a substantial human health risk. Besides being causative agents for gastrointestinal disease after ingestion of a live larva, and an allergic reaction after consuming/handling infected fish, there is proof-of-principle for hidden allergic concerns. Several anisakid allergens are highly resistant, and in this way may be transmitted to meat by use of fishmeal as a feed component for livestock. To consolidate this hypothesis of transmissibility, a controlled chicken feeding trial using Anisakidae-contaminated feed was conducted.Methods: Anisakid larvae were collected from codfish and freeze-dried according to fishmeal manufacturing conditions. This larvaemeal was then administered to chickens, and after three weeks of exposure, blood and muscle samples were subjected to a targeted proteomic analysis aiming at detecting anisakid peptides. Results and discussion: Results demonstrated that peptides from at least six A. simplex allergens were transferred from the feed to the chicken meat and blood. If future experiments confirm a remaining allergenic potency of these peptides in humans, it would significantly change the importance of these zoonotic nematodes from originally a purely fishborne food risk to potentially a wider risk from several food sources.

Candida albicans is an emerging multidrug-resistant opportunistic pathogen representing an important source of invasive disease in humans and generating high healthcare costs worldwide. The development of a rapid and simple antifungal susceptibility test (AFST) could limit the spread of this disease, increase the efficiency of treatment, and lower the risk of developing resistant strains. We developed a microfluidic chip containing an array of microwells that were designed to trap the cells and perform rapid antifungal susceptibility tests using optical nanomotion detection (ONMD). Yeast cell entrapment in a microwell allows for a very rapid exchange of growth medium with the antifungal, which enables performing single-cell ONMD measurements on the same cell before and after antifungal treatment. The exposure to a low concentration of the antifungal caspofungin or flucanozole induced a significant decrease in the nanomotion signal, demonstrating the high sensitivity of this technique. We used this chip to quantify the real-time response of individual C. albicans cells to the antifungal treatment in as fast as 10 min. This simple and label-free technique could be further developed into a simple-to-use device that allows the performance of fast AFST as part of a routine hospital procedure in developed and also eventually developing world countries.

Neofusicoccum parvum is a fungal plant pathogen of a wide range of hosts but knowledge about the virulence factors of N. parvum and host–pathogen interactions is rather limited. The molecules involved in the interaction between N. parvum and Eucalyptus are mostly unknown, so we used a multi-omics approach to understand pathogen–host interactions. We present the first comprehensive characterization of the in vitro secretome of N. parvum and a prediction of protein–protein interactions using a dry-lab non-targeted interactomics strategy. We used LC-MS to identify N. parvum protein profiles, resulting in the identification of over 400 proteins, from which 117 had a different abundance in the presence of the Eucalyptus stem. Most of the more abundant proteins under host mimicry are involved in plant cell wall degradation (targeting pectin and hemicellulose) consistent with pathogen growth on a plant host. Other proteins identified are involved in adhesion to host tissues, penetration, pathogenesis, or reactive oxygen species generation, involving ribonuclease/ribotoxin domains, putative ricin B lectins, and necrosis elicitors. The overexpression of chitosan synthesis proteins during interaction with the Eucalyptus stem reinforces the hypothesis of an infection strategy involving pathogen masking to avoid host defenses. Neofusicoccum parvum has the molecular apparatus to colonize the host but also actively feed on its living cells and induce necrosis suggesting that this species has a hemibiotrophic lifestyle.

The family Anisakidae, mainly represented by Anisakis simplex s.l. and Pseudoterranova decipiens, encompasses zoonotic nematodes infecting many marine fish. Both are responsible for gastrointestinal disease in humans after ingestion of a live larva by consumption of undercooked fish, and, in the case of A. simplex, an allergic reaction may occur after consuming or even handling infected fish. Due to its phylogenetic relatedness with A. simplex, few studies investigated the allergenic potential of P. decipiens, yet none of them focused on its excretory/secretory (E/S) proteins that easily get missed when working solely on extracts from crushed nematodes. Moreover, these E/S allergens remain behind even when the larva has been removed during fish quality processing. Therefore, the aim was to investigate if Anisakis-like allergens could also be detected in both crushed and E/S P. decipiens protein extract using targeted mass spectrometry analysis and immunological methods. The results confirmed that at least five A. simplex allergens have homologous proteins in P. decipiens; a result that emphasizes the importance of also including E/S protein extracts in proteomic studies. Not only A. simplex, but also P. decipiens should therefore be considered a potential source of allergens that could lead to hypersensitivity reactions in humans.

The development of spots or lesions symptomatic of common scab on root and tuber crops is caused by few pathogenic Streptomyces with Streptomyces scabiei 87-22 as the model species. Thaxtomin phytotoxins are the primary virulence determinants, mainly acting by impairing cellulose synthesis, and their production in S. scabiei is in turn boosted by cello-oligosaccharides released from host plants. In this work we aimed to determine which molecules and which biosynthetic gene clusters (BGCs) of the specialized metabolism of S. scabiei 87-22 show a production and/or a transcriptional response to cello-oligosaccharides. Comparative metabolomic analyses revealed that molecules of the virulome of S. scabiei induced by cellobiose and cellotriose include (i) thaxtomin and concanamycin phytotoxins, (ii) desferrioxamines, scabichelin and turgichelin siderophores in order to acquire iron essential for housekeeping functions, (iii) ectoine for protection against osmotic shock once inside the host, and (iv) bottromycin and concanamycin antimicrobials possibly to prevent other microorganisms from colonizing the same niche. Importantly, both cello-oligosaccharides reduced the production of the spore germination inhibitors germicidins thereby giving the 'green light' to escape dormancy and trigger the onset of the pathogenic lifestyle. For most metabolites - either with induced or reduced production - cellotriose was revealed to be a slightly stronger elicitor compared to cellobiose, supporting an earlier hypothesis which suggested the trisaccharide was the real trigger for virulence released from the plant cell wall through the action of thaxtomins. Interestingly, except for thaxtomins, none of these BGCs' expression seems to be under direct control of the cellulose utilization repressor CebR suggesting the existence of a yet unknown mechanism for switching on the virulome. Finally, a transcriptomic analysis revealed nine additional cryptic BGCs that have their expression awakened by cello-oligosaccharides, suggesting that other and yet to be discovered metabolites could be part of the virulome of S. scabiei.

Cellulose being the most abundant polysaccharide on earth, beta-glucosidases hydrolyzing cello-oligosaccharides are key enzymes to fuel glycolysis in microorganisms developing on plant material. In Streptomyces scabiei, the causative agent of common scab in root and tuber crops, a genetic compensation phenomenon safeguards the loss of the gene encoding the cello-oligosaccharide hydrolase BglC by awakening the expression of alternative beta-glucosidases. Here we reveal that the BglC compensating enzyme BcpE2 is the GH3-family beta-glucosidase that displays the highest reported substrate promiscuity able to release the glucose moiety of all tested types of plant-derived heterosides (aryl β-glucosides, monolignol glucosides, cyanogenic glucosides, anthocyanosides, and coumarin heterosides). BcpE2 structure analysis highlighted a large cavity in the PA14 domain that covers the active site, and the high flexibility of this domain would allow proper adjustment of this cavity for disparate heterosides. The exceptional substrate promiscuity of BcpE2 provides microorganisms a versatile tool for scavenging glucose from plant-derived nutrients that widely vary in size and structure. Importantly, scopolin is the only substrate commonly hydrolyzed by both BglC and BcpE2 thereby generating the potent virulence inhibitor scopoletin. Next to fueling glycolysis, both enzymes thus also interfere with the plant defense mechanisms to fine-tune the strength of virulence.

Streptomyces scabies is a phytopathogen associated with common scab disease. This is mainly attributed to its ability to produce the phytotoxin thaxtomin A, the biosynthesis of which is triggered by cellobiose. During a survey of other metabolites released in the presence of cellobiose, we discovered additional compounds in the thaxtomin-containing extract from Streptomyces scabies. Structural analysis by mass spectrometry (MS) and nuclear magnetic resonance (NMR) revealed that these compounds are amino acid sequence variants of the TOR (target of rapamycin) kinase (TORK) pathway-inhibitory lipopeptide rotihibin A, and the main compounds were named rotihibins C and D. In contrast to thaxtomin, the production of rotihibins C and D was also elicited in the presence of glucose, indicating different regulation of their biosynthesis. Through a combination of shotgun and targeted proteomics, the putative rotihibin biosynthetic gene cluster rth was identified in the publicly available genome of S. scabies 87-22. This cluster spans 33 kbp and encodes 2 different nonribosomal peptide synthetases (NRPSs) and 12 additional enzymes. Homologous rth biosynthetic gene clusters were found in other publicly available and complete actinomycete genomes. Rotihibins C and D display herbicidal activity against Lemna minor and Arabidopsis thaliana at low concentrations, shown by monitoring the effects on growth and the maximal photochemistry efficiency of photosystem II. IMPORTANCE Rotihibins A and B are plant growth inhibitors acting on the TORK pathway. We report the isolation and characterization of new sequence analogues of rotihibin from Streptomyces scabies, a major cause of common scab in potato and other tuber and root vegetables. By combining proteomics data with genomic analysis, we found a cryptic biosynthetic gene cluster coding for enzyme machinery capable of rotihibin production. This work may lead to the biotechnological production of variants of this lipopeptide to investigate the exact mechanism by which it can target the plant TORK pathway in Arabidopsis thaliana. In addition, bioinformatics revealed the existence of other variants in plant-associated Streptomyces strains, both pathogenic and nonpathogenic species, raising new questions about the actual function of this lipopeptide. The discovery of a module in the nonribosomal peptide synthetase (NRPS) that incorporates the unusual citrulline residue may improve the prediction of peptides encoded by cryptic NRPS gene clusters.

2. Abstract The development of spots or lesions symptomatic of the common scab disease on root and tuber crops is caused by few pathogenic Streptomyces with Streptomyces scabiei 87-22 as the model species. Thaxtomin phytotoxins are the primary virulence determinants, mainly acting by impairing cellulose synthesis, and their production in S . scabiei is in turn boosted by the cello-oligosaccharides released from host plants. In this work we aimed to determine which molecules and which biosynthetic gene clusters (BGCs) of the specialized metabolism of S. scabiei 87-22 show a production and/or transcriptional response to cello-oligosaccharides. Comparative metabolomic and transcriptomic analyses revealed that molecules of the virulome of S. scabiei induced by cellobiose and cellotriose include i) thaxtomins and concanamycins phytotoxins (and to a lesser extent N-coronafacoyl-L-isoleucine), ii) desferrioxamines, scabichelin and turgichelin siderophores in order to acquire iron essential for housekeeping functions, iii) ectoine for protection against osmotic shock once inside the host, and iv) bottromycins and concanamycins antimicrobials possibly to prevent other microorganisms from colonizing the same niche. Importantly, both cell-oligosaccharides reduced the production of the spore germination inhibitors germicidins and the plant growth regulators rotihibins. The metabolomic study also revealed that cellotriose is in general a more potent elicitor of the virulome compared to cellobiose. This result supports an earlier hypothesis that suggested that the trisaccharide would be the real virulence-triggering factor released from the plant cell wall through the action of thaxtomins. Interestingly, except for thaxtomins, none of these BGCs’ expression seems to be under direct control of the cellulose utilization repressor CebR suggesting the existence of another master regulator sensing the internalization of cello-oligosaccharides. Finally, we found nine additional cryptic and orphan BGCs that have their expression awakened by cello-oligosaccharides, demonstrating that other and yet to be discovered metabolites are part of the virulome of S . scabiei . 3. Impact statement Unveiling the environmental triggers that signal proper conditions for host colonization and what is the composition of the arsenal of metabolites specialized for this task (the virulome) is key to understand host-pathogen interactions. In this work, focused on the induction of the common scab disease caused by Streptomyces species, we provided further knowledge to both aspects i.e., i) highlighting the capability of cellotriose to trigger the entire virulome and not only the production of thaxtomin phytotoxins, and ii) identifying the set of metabolites that specifically respond to cello-oligosaccharides emanating from the plant under attack. Importantly, we also revealed that the expression of nine cryptic/orphan biosynthetic gene clusters (BGCs) involved in the production of unknown compounds was drastically activated upon cello-oligosaccharides import suggesting that a significant part of the virulome of S . scabiei remains to be discovered. Finally, we unexpectedly found that the expression control of most of the known and cryptic BGCs does not depend on the cello-oligosaccharide utilization repressor CebR which suggests the existence of another and yet unknown master regulator of the virulence in S . scabiei . 4. Significance as a BioResource to the community Not Applicable 5. Outcome Not Applicable 6. Data summary [A section describing all supporting external data including the DOI(s) and/or accession numbers(s), and the associated URL.] The authors confirm all supporting data, code and protocols have been provided within the article or through supplementary data files. RNAseq data were publicly deposited, and our experimental and analytical pipeline were described on the GEO database repository (Accession number: GSE181490)

The first step in the infection of fungal pathogens in humans is the adhesion of the pathogen to host tissue cells or abiotic surfaces such as catheters and implants. One of the main players involved in this are the expressed cell wall adhesins. Here, we review the Flo adhesin family and their involvement in the adhesion of these yeasts during human infections. Firstly, we redefined the Flo adhesin family based on the domain architectures that are present in the Flo adhesins and their functions, and set up a new classification of Flo adhesins. Next, the structure, function, and adhesion mechanisms of the Flo adhesins whose structure has been solved are discussed in detail. Finally, we identified from Pfam database datamining yeasts that could express Flo adhesins and are encountered in human infections and their adhesin architectures. These yeasts are discussed in relation to their adhesion characteristics and involvement in infections.

The cytochrome P450 (CYP) monooxygenase superfamily offers the unique ability to catalyze regio-and stereospecifical oxidation of a non-activated C-H bond. CYPs found applications in the synthesis of pharmaceuticals and drug metabolites as well as in bioremediation. They are typically used in whole-cell bioconversion processes, due to their low stability and the need for a redox partner and cofactor. Unfortunately, substrate uptake and/or product transport limitations are frequently encountered and side reactions occur due to other enzymes in the cellular environment. Here, we present a proof-of-principle of a novel cell-free cytochrome P-450 nanocatalyst based on surface display on bacterial outer membrane vesicles. The self-sufficient CYP 102A1 from Bacillus megaterium was engineered to be translocated on the outer membrane vesicles of Escherichia coli . The resulting vesicles can simply be isolated from the culture supernatant. Moreover, no expensive and elaborate enzyme purification is required. This approach shows great promise as an alternative strategy to recombinantly produce CYP enzymes for a variety of applications, such as in fine chemical production and in the development of biosensors.