Biology subjects

Bunk, B.

Publications and source records attributed to Bunk, B..

At least 19 recordsLinked to original sources

bioRxiv2026

Old Compound, New Context: Naphthocyclinones Mediate Microbial Competition in Wild Bee Nests

Although thousands of microbial specialized metabolites have been identified, the ecological functions of most remain unknown. Naphthocyclinones are aromatic polyketide antibiotics discovered more than five decades ago, yet their biological role has remained elusive. Investigating the microbial community of the oligolectic ivy bee (Colletes hederae), a bacterial community that included several Streptomyces species and members of the class Bacilli was recovered from fermented nest provisions. One Streptomyces isolate, B-004T (DSM 121525T = LMG 34598T), was identified as representing a novel species based on polyphasic taxonomic studies, for which the name Streptomyces hederae sp. nov. is proposed. This strain showed potent antibacterial activity against co-isolated Gram-positive bacteria as well as Paenibacillus larvae, the causative agent of American foulbrood. Bioassay-guided fractionation coupled with liquid chromatography-mass spectrometry analysis led to the identification of naphthocyclinone congeners as the active metabolites. Whole-genome sequencing and genome mining revealed a type II polyketide synthase biosynthetic gene cluster closely related to that of the characterized naphthocyclinone pathway. Targeted deletion of the cluster-encoded ketosynthase gene (B-004_07360) abolished naphthocyclinone production and resulted in the complete loss of antibacterial activity, whereas heterologous overexpression of the Streptomyces antibiotic regulatory protein gene papR2 significantly increased antibiotic production, confirming the function of the naphthocyclinone biosynthetic gene cluster. Furthermore, naphthocyclinone biosynthesis was found to be induced by sympatric bacterial isolates from bee nests. Together, our findings provide the first evidence for an ecological function of naphthocyclinones as mediators of bacterial competition in wild bee nests and highlight their potential as antimicrobial substances against P. larvae.

microbiology↗

bioRxiv2026

The StrainDiscoveryDatabase: an open framework for standardized microbial strain data

The vast amount of existing data on microbial strains holds immense potential to revolutionize bioindustry through the application of Artificial Intelligence (AI). However, the training of robust predictive AI models requires large-scale, unified, and non-redundant microbial datasets, which is currently severely hindered by the deep fragmentation of the data and the existence of synonymous strain identifiers in different culture collections. To overcome these infrastructural bottlenecks, we have established the StrainDiscoveryDatabase (SDD), a comprehensive, machine-readable dataset encompassing over 6.2 million harmonized data points for 256,889 microbial strains. The SDD does not rely on its own data repository, but rather on existing data that is retrieved on the fly from highly curated databases. Through an automated pipeline phenotypic, genotypic, and contextual data are systematically retrieved via the Application Programming Interfaces (APIs) of the Bacterial Diversity database (BacDive), the Microbial Resource Research Infrastructure Information System (MIRRI-IS) and the catalogue of the DSMZ. In order to reliably resolve synonymous strain identifiers, the StrainInfo database and its identification tools are employed, enabling the accurate deduplication and unification of records from disparate sources. The resulting aggregated, globally unique dataset is provided in a highly standardized JSON format in strict adherence to the FAIR data principles. By bridging isolated database silos and linking distributed knowledge to discrete biological entities, the SDD provides a high-quality, foundational resource designed to accelerate trait-based strain discovery, large-scale comparative analysis, and machine learning applications, thereby supporting the translation of the extensive existing knowledge on microbial traits to bioindustrial applications.

microbiology↗

bioRxiv2026

Unveiling the taxonomic diversity and unprecedented biosynthetic treasure of the phylum Myxococcota

Natural products remain vital sources of therapeutics, particularly anti-infectives, and members of the phylum Myxococcota constitute an especially rich reservoir for their discovery. Based on decades of microbiological efforts, we present 154 new Myxococcota genomes and propose a revised taxonomy expanding the number of described families from 11 to 28 and genera from 32 to 90. Comparison with an equivalent set from the prime source Actinomycetota shows that Myxococcota possess a comparable biosynthetic diversity, underscoring their promise for large-scale isolation and sequencing efforts. The vast untapped potential reflected in 2,387 uncharacterized gene cluster families is highlighted by genome mining efforts, yielding four validated compounds exhibiting novel chemistry, including myxolutamids and myxopentacins. We show that many Myxococcota-derived natural products, such as myxolutamid A and two new sorangicin derivatives, are conserved within taxonomic lineages. New described families thus bear high biosynthetic potential underpinning the importance of precise taxonomic classification guiding targeted drug discovery.

microbiology↗

bioRxiv2025

Viral infection collapses intracytoplasmic membrane integrity and autotrophic metabolism in ammonia-oxidizing Nitrosomonas europaea

Ammonia-oxidizing bacteria (AOB) catalyze the first and rate-limiting step of nitrification. They are essential for nitrogen cycling in engineered and natural environments, yet little is known about their viruses or the consequences of phage infection for host physiology. Here, we report the isolation and characterization of a novel lytic bacteriophage, vB_NeuP-Nir1 (Nir1), infecting the model AOB Nitrosomonas europaea. Phage Nir1 was highly virulent, ceased ammonia oxidation within hours, and caused complete lysis of host populations even at multiplicities of infection as low as 10-6. Electron microscopy revealed drastic host cell remodeling during infection, including pronounced cell bloating and large-scale disintegration of intracytoplasmic membranes. Integrated transcriptomic and metabolomic analyses showed that loss of these ATP and reducing equivalent generating membrane systems was accompanied by signatures of compromised lipid homeostasis and collapse of autotrophic CO2 fixation. In parallel, Nir1 infection induced metabolic rewiring of the host, including upregulation of uptake systems for nucleic acids, amino acids, and small organic compounds, increased expression of iron acquisition and putative iron-dependent respiratory components, as well as accumulation of metabolites associated with membrane breakdown and stabilization of viral DNA. Together, these results provide the first detailed mechanistic insight into phage-induced host modulation in a chemolithoautotrophic nitrifier. Our study establishes the Nir1-N. europaea system as a model for investigating virus-host interactions in AOB and lays the foundation for assessing the role of phages in shaping nitrification and nitrogen cycling in engineered and natural ecosystems.

microbiology↗

bioRxiv2024

EnteroBase in 2025: exploring the genomic epidemiology of bacterial pathogens

This paper presents an update on the content, accessibility and analytical tools of the EnteroBase platform for web-based pathogen genome analysis. EnteroBase provides manually curated databases of genome sequence data and associated metadata from currently >1.1 million bacterial isolates, more recently including Streptococcus spp. and Mycobacterium tuberculosis. We have implemented the genome-based detection of antimicrobial resistance determinants and the new bubble plot graphical tool for visualising bacterial genomic population structures, based on pre-computed hierarchical clusters. Access to data and analysis tools is provided through an enhanced graphical user interface and a new application programming interface (RESTful API). EnteroBase is now being developed and operated by an international consortium, to accelerate the development of the platform and ensure the longevity of the resources built. EnteroBase can be accessed at https://enterobase.warwick.ac.uk as well as https://enterobase.dsmz.de. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=105 SRC="FIGDIR/small/608032v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@88ff78org.highwire.dtl.DTLVardef@3c426eorg.highwire.dtl.DTLVardef@2d8481org.highwire.dtl.DTLVardef@5644bb_HPS_FORMAT_FIGEXP M_FIG C_FIG

genomics↗

bioRxiv2024

Adaptive diversification through structural variation in barley

Pangenomes are collections of annotated genome sequences of multiple individuals of a species. The structural variants uncovered by these datasets are a major asset to genetic analysis in crop plants. Here, we report a pangenome of barley comprising long-read sequence assemblies of 76 wild and domesticated genomes and short-read sequence data of 1,315 genotypes. An expanded catalogue of sequence variation in the crop includes structurally complex loci that have become hot spots of gene copy number variation in evolutionarily recent times. To demonstrate the utility of the pangenome, we focus on four loci involved in disease resistance, plant architecture, nutrient release, and trichome development. Novel allelic variation at a powdery mildew resistance locus and population-specific copy number gains in a regulator of vegetative branching were found. Expansion of a family of starch-cleaving enzymes in elite malting barleys was linked to shifts in enzymatic activity in micro-malting trials. Deletion of an enhancer motif is likely to change the developmental trajectory of the hairy appendages on barley grains. Our findings indicate that rapid evolution at structurally complex loci may have helped crop plants adapt to new selective regimes in agricultural ecosystems.

plant biology↗

bioRxiv2023

COMPLETE GENOME SEQUENCE OF VIBRIO SYNGNATHI SP. NOV., A FISH PATHOGEN, ISOLATED FROM THE KIEL FJORD

A new Vibrio strain K08M4T was isolated from the broad-nosed pipefish Syngnathus typhle in the Kiel Fjord. Infection experiments revealed that K08M4T is highly virulent for juvenile pipefish. Cells of strain K08M4T are Gram-stain-negative, curved rod-shaped and motile by means of a single polar flagellum. The strain can grow aerobically at 9 to 40{degrees}C, at pH 4 to 10.5 and tolerates up to 12% (w/v) NaCl. The most prevalent (> 10%) cellular fatty acids of K08M4T were C16:1{omega} 7c and C16:0. Whole-genome comparisons revealed that K08M4T represents a separate evolutionary lineage which is distinct from other Vibrio species and falls within the Vibrio Splendidus clade. The genome is 4,886,292 bp in size, consists of two circular chromosomes (3,298,328 bp, 1,587,964 bp), and comprises 4,178 protein-coding genes and 175 RNA genes. In this study, we describe the phenotypic features of the new isolate and present the annotation and analysis of its complete genome sequence. Based on these data, the new isolate represents a new species for which we propose the name Vibrio syngnathi. The type strain is K08M4T (=DSM 109818T). Supplementary materialOne supplementary figure and six supplementary table are available with the online version of the Manuscript.

microbiology↗

bioRxiv2023

Genomics of the "tumorigenes" clade of the family Rhizobiaceae and description of Rhizobium rhododendri sp. nov.

Tumorigenic members of the family Rhizobiaceae, known as agrobacteria, are responsible for crown and cane gall diseases of various agricultural crops worldwide. Tumorigenic agrobacteria are commonly found in the genera Agrobacterium, Allorhizobium, and Rhizobium. In this study, we analyzed a distinct "tumorigenes" clade of the genus Rhizobium, which includes the tumorigenic species Rhizobium tumorigenes, as well as strains causing crown gall disease on rhododendron. Here, high quality, closed genomes of representatives of the "tumorigenes" clade were generated, followed by comparative genomic and phylogenomic analyses. Additionally, phenotypic characteristics of representatives of the "tumorigenes" clade were analyzed. Our results showed that the tumorigenic strains isolated from rhododendron represent a novel species of the genus Rhizobium for which the name Rhizobium rhododendri sp. nov. is proposed. This species also includes additional strains originating from blueberry and Himalayan blackberry in USA, whose genome sequences were retrieved from GenBank. Both R. tumorigenes and R. rhododendri contain multipartite genomes, including a chromosome, putative chromids, and megaplasmids. Synteny and phylogenetic analyses indicated that a large putative chromid of R. rhododendri resulted from the cointegration of an ancestral megaplasmid and two putative chromids, following its divergence from R. tumorigenes. Moreover, gene clusters specific for both species of the "tumorigenes" clade were identified, and their biological functions and roles in ecological diversification of R. rhododendri and R. tumorigenes were predicted and discussed.

microbiology↗

bioRxiv2022

Bursts in biosynthetic gene cluster transcription are accompanied by surges of natural compound production in the myxobacterium Sorangium sp.

We have investigated the time course of genome-wide transcription in the myxobacterium Sorangium sp. So ce836 in relation to its production of natural compounds. Time-resolved RNA sequencing revealed that core biosynthesis genes from 48 biosynthetic gene clusters (BGCs; 92% of all BGCs encoded in the genome) were actively transcribed at specific time points in a batch culture. The majority (80%) of polyketide synthase and non-ribosomal peptide synthetase genes displayed distinct peaks of transcription during exponential bacterial growth. Strikingly, these bursts in BGC transcriptional activity were associated with surges in the production of known natural compounds, indicating that their biosynthesis was critially regulated at the transcriptional level. In contrast, BGC read counts from single time points had limited predictive value about biosynthetic activity, since transcription levels varied >100-fold among BGCs with detected natural products. Taken together, our time-course data provide unique insights into the dynamics of natural compound biosynthesis and its regulation in a wild-type myxobacterium, challenging the commonly cited notion of preferential BGC expression under nutrient-limited conditions. The close association observed between BGC transcription and compound production warrants additional efforts to develop genetic engineering tools for myxobacterial producer strains, to boost compound yields by manipulating transcriptional activity.

genomics↗

bioRxiv2022

Evolution of resilience against heat stress in a red-tide dinoflagellate

"Red tides" are harmful algal blooms (HABs) caused by dinoflagellate microalgae that accumulate toxins lethal to other organisms, including humans via consumption of contaminated seafood. Increasingly frequent, HABs are driven by a combination of environmental factors including nutrient enrichment, particularly in warm waters. Here, we present the de novo assembled genome (~4.75 Gbp), transcriptome, proteome, and metabolome from Prorocentrum cordatum, a globally abundant, bloom-forming dinoflagellate. Using axenic algal cultures, we studied the molecular mechanisms that underpin response to temperature stress, which is relevant to current ocean warming trends. We discovered a complementary interplay between RNA editing and exon usage that regulates the expression and functional diversity of biomolecules, reflected by reduction in photosynthesis, central metabolism, and protein synthesis. Our multi-omics analyses uncover the molecular response to heat stress in an important HAB species, which is driven by complex gene structures in a large, high-G+C genome, combined with multi-level transcriptional regulation.

genomics↗

bioRxiv2022

Two new Rhizobiales species isolated from root nodules of common sainfoin (Onobrychis viciifolia) show different plant colonization strategies

Root nodules of legume plants are primarily inhabited by rhizobial nitrogen-fixing bacteria. Here we propose two new Rhizobiales species isolated from root nodules of common sainfoin (Onobrychis viciifolia), as shown by core-gene phylogeny, overall genome relatedness indices and pan-genome analysis. Mesorhizobium onobrychidis sp. nov., actively induces nodules, and achieves atmospheric nitrogen and carbon dioxide fixation. This species appears to be depleted in motility genes, and is enriched in genes for direct effects on plant growth performance. Its genome reveals functional and plant growth-promoting signatures like a large unique chromosomal genomic island with high density of symbiotic genetic traits. Onobrychidicola muellerharveyae gen. nov. sp. nov., is described as type species of the new genus Onobrychidicola in Rhizobiaceae. This species comprises unique genetic features and plant growth-promoting traits (PGPTs), which strongly indicate its function in biotic stress reduction and motility. We applied a newly developed bioinformatics approach for in silico prediction of PGPTs (PGPT-Pred), which supports the different lifestyles of the two new species and the plant growth-promoting performance of M. onobrychidis in the greenhouse trial.

microbiology↗

bioRxiv2021

Discovery and Biosynthesis of Persiathiacins: Unusual Polyglycosylated Thiopeptides Active against Multi-drug resistant Tuberculosis

Thiopeptides are ribosomally biosynthesized and post-translationally modified peptides (RiPPs) that potently inhibit the growth of Gram-positive bacteria by targeting multiple steps in protein biosynthesis. The poor pharmacological properties of thiopeptides, in particular their low aqueous solubility, has hindered their development into clinically useful antibiotics. Antimicrobial activity screens of a library of Actinobacterial extracts led to discovery of the novel polyglycosylated thiopeptides persiathiacins A and B from Actinokineospora sp. UTMC 2475 and Actinokineospora sp. UTMC 2448. Persiathiacin A is active against methicillin-resistant Staphylococcus aureus (MRSA) and several Mycobacterium tuberculosis strains, including drug-resistant and multidrug-resistant clinical isolates, and does not significantly affect the growth of ovarian cancer cells at concentrations up to 400 M. In vitro translation assays showed that, like other thiopeptide antibiotics, persiathiacin A targets protein biosynthesis. Polyglycosylated thiopeptides are extremely rare and nothing is known about their biosynthesis. Sequencing and analysis of the Actinokineospora sp. UTMC 2448 genome enabled identification of the putative persiathiacin biosynthetic gene cluster. A cytochrome P450 encoded by this gene cluster catalyses the hydroxylation of nosiheptide in vitro and in vivo, consistent with the proposal that the cluster directs persiathiacin biosynthesis. Several genes in the cluster encode homologues of enzymes known to catalyse the assembly and attachment of deoxysugars during the biosynthesis of other classes of glycosylated natural products. The discovery of the persiathiacins and their biosynthetic gene cluster thus provides the basis for the development of biosynthetic engineering approaches to the creation of novel (poly)glycosylated thiopeptide derivatives with enhanced pharmacological properties.

microbiology↗

bioRxiv2021

Unraveling the critical growth factors for stable cultivation of (nano-sized) Micrarchaeota

Micrarchaeota are members of the archaeal DPANN superphylum. These so far poorly characterized archaea have been found to have reduced genomes and likely depend on interactions with host organisms for growth and survival. Here we report on the enrichment of the first stable co-culture of a member of the Micrarchaeota together with its host, as well as the isolation of the latter. Electron microscopic analysis suggest that growth is dependent on the physical interaction of the two organisms within a biofilm. The interaction seems to be ensured by the necessity to grow in form of a biofilm. Furthermore, transcriptomic analyses indicate a shift towards biofilm formation of the host as a result of co-cultivation. Finally, genomic, metabolomic, extracellular polymeric substance (EPSs) and lipid content analyses reveal that the Micrarchaeon symbiont relies on the acquisition of metabolites from its host and thereby provide first insights into the basis of symbiont-host interactions.

microbiology↗

bioRxiv2021

HIGH VIRULENCE SELECTS FOR FAST HOST RESISTANCE EVOLUTION

Parasites and pathogens vary strikingly in their virulence and the resulting selection they impose on their hosts. While the evolution of different virulence levels is well studied, the evolution of host resistance in response to different virulence levels is less understood and as of now mainly based on observations and theoretical predictions with few experimental tests. Increased virulence can increase selection for host resistance evolution if resistance costs are outweighed by the benefits of avoiding infection. To test this, we experimentally evolved the bacterium Vibrio alginolyticus in the presence of two variants of the filamentous phage, VALG{Phi}8, that differ in their virulence. The bacterial host exhibited two alternative defence strategies against future phage infection: (1) super infection exclusion (SIE) whereby phage-infected cells were immune to subsequent infection at a cost of reduced growth, and (2) surface receptor mutations (SRM) in genes encoding the MSHA type-IV pilus providing resistance to infection by preventing phage attachment. While SIE emerged rapidly against both phages, SRM evolved faster against the high virulence compared to the low virulence phage. Using a mathematical model of our system we show that increasing virulence strengthens selection for SRM due to the higher costs of infection suffered by SIE immune hosts. In both the experiments and the model, higher levels of SRM in the host population drove more rapid phage extinction. Thus, by accelerating the evolution of host resistance, more virulent phages caused shorter epidemics.

evolutionary biology↗

bioRxiv2019

PROMA PLASMIDS ARE INSTRUMENTAL IN THE DISSEMINATION OF LINURON CATABOLIC GENES BETWEEN DIFFERENT GENERA

PromA plasmids are broad host range plasmids, which are often cryptic and hence have an uncertain ecological role. We present three novel PromA {gamma} plasmids which carry genes associated with degradation of the phenylurea herbicide linuron, two (pPBL-H3-2 and pBPS33-2) of which originate from unrelated Hydrogenophaga hosts isolated from different environments, and one (pEN1) which was exogenously captured from an on-farm biopurification system. Both Hydrogenophaga plasmids carry all three necessary gene clusters determining the three main steps for conversion of linuron to Krebs cycle intermediates, while pEN1 only determines the initial linuron hydrolysis step. Linuron catabolic gene clusters that determine the same step were identical on all plasmids, encompassed in differently arranged constellations and characterized by the presence of multiple IS1071 elements. In all plasmids except pEN1, the insertion spot of the catabolic genes in the PromA {gamma} plasmids was the same. Highly similar PromA plasmids carrying the linuron degrading gene cargo at the same insertion spot were were previously identified in linuron degrading Variovorax sp. Interestingly, in both Hydrogenophaga populations not every PromA plasmid copy carries catabolic genes. The results indicate that PromA plasmids are important vehicles of linuron catabolic gene dissemination, rather than being cryptic and only important for the mobilization of other plasmids.

genomics↗

bioRxiv2019

Comparative genomics unravels mechanisms of genetic adaptation for the catabolism of the phenylurea herbicide linuron in Variovorax

Biodegradation of the phenylurea herbicide linuron appears a specialization within a specific clade of the Variovorax genus. The linuron catabolic ability is likely acquired by horizontal gene transfer but the mechanisms involved are not known. The full genome sequences of six linuron degrading Variovorax strains isolated from geographically distant locations were analyzed to acquire insight in the mechanisms of genetic adaptation towards linuron metabolism in Variovorax. Whole genome sequence analysis confirmed the phylogenetic position of the linuron degraders in a separate clade within Variovorax and indicated their unlikely origin from a common ancestral linuron degrader. The linuron degraders differentiated from non-degraders by the presence of multiple plasmids of 20 to 839 kb, including plasmids of unknown plasmid groups. The linuron catabolic gene clusters showed (i) high conservation and synteny and (ii) strain-dependent distribution among the different plasmids. All were bordered by IS1071 elements forming composite transposon structures appointing IS1071 as key for catabolic gene recruitment. Most of the strain carried at least one broad host range plasmid that might have been a second instrument for catabolic gene acquisition. We conclude that clade 1Variovorax strains, despite their different geographical origin, made use of a limited genetic repertoire to acquire linuron biodegradation.\n\nImportanceThe genus Variovorax and especially a clade of strains that phylogenetically separates from the majority of Variovorax species, appears to be a specialist in the biodegradation of the phenyl urea herbicide linuron. Horizontal gene transfer (HGT) likely played an essential role in the genetic adaptation of those strain to acquire the linuron catabolic genotype. However, we do not know the genetic repertoire involved in this adaptation both regarding catabolic gene functions as well as gene functions that promote HGT neither do we know how this varies between the different strains. These questions are addressed in this paper by analyzing the full genome sequences of six linuron degrading Variovorax strains. This knowledge is important for understanding the mechanisms that steer world-wide genetic adaptation in a particular species and this for a particular phenotypic trait as linuron biodegradation.

microbiology↗

bioRxiv2019

Global genomic population structure of Clostridioides difficile

Clostridioides difficile is the primary infectious cause of antibiotic-associated diarrhea. Local transmissions and international outbreaks of this pathogen have been previously elucidated by bacterial whole-genome sequencing, but comparative genomic analyses at the global scale were hampered by the lack of specific bioinformatic tools. Here we introduce EnteroBase, a publicly accessible database (http://enterobase.warwick.ac.uk) that automatically retrieves and assembles C. difficile short-reads from the public domain, and calls alleles for core-genome multilocus sequence typing (cgMLST). We demonstrate that the identification of highly related genomes is 89% consistent between cgMLST and single-nucleotide polymorphisms. EnteroBase currently contains 13,515 quality-controlled genomes which have been assigned to hierarchical sets of single-linkage clusters by cgMLST distances. Hierarchical clustering can be used to identify populations of C. difficile at all epidemiological levels, from recent transmission chains through to pandemic and endemic strains, and is largely compatible with prior ribotyping. Hierarchical clustering thus enables comparisons to earlier surveillance data and will facilitate communication among researchers, clinicians and public-health officials who are combatting disease caused by C. difficile.

microbiology↗

bioRxiv2019

Discovery of a polybrominated aromatic secondary metabolite from a planctomycete points at an ambivalent interaction with its macroalgae host

The roles of the majority of bacterial secondary metabolites, especially those from uncommon sources are yet elusive even though many of these compounds show striking biological activities. To further investigate the secondary metabolite repertoire of underexploited bacterial families, we chose to analyze a novel representative of the yet untapped bacterial phylum Planctomycetes for the production of secondary metabolites under laboratory culture conditions. Development of a planctomycetal high density cultivation technique in combination with high resolution mass spectrometric analysis revealed Planctomycetales strain 10988 to produce the plant toxin 3,5 dibromo p-anisic acid. This molecule represents the first secondary metabolite reported from any planctomycete. Genome mining revealed the biosynthetic origin of this doubly brominated secondary metabolite and a biosynthesis model for the com-pound was devised. Comparison of the biosynthetic route to biosynthetic gene clusters responsible for formation of polybrominated small aromatic compounds reveals evidence for an evolutionary link, while the compounds herbicidal activity points towards an ambivalent role of the metabolite in the planctomycetal ecosystem.

microbiology↗