Characterization of Mucosal Dysbiosis of Early Colonic Neoplasia

AbstractAberrant crypt foci (ACF) are the earliest morphologically identifiable lesion in the colon that can be detected by high-definition chromoendoscopy with contrast dye-spray. Although frequently associated with synchronous adenomas, their role in colorectal tumor development, particularly in the proximal colon, is still not clear. The goal of this study was to evaluate the profile of colon-associated bacteria associated with proximal ACF and to investigate their relationship to the presence and subtype of synchronous polyps present throughout the colon. Forty-five subjects undergoing a screening or surveillance colonoscopy were included in this retrospective study. Our study cohort included a total of 16 subjects with no identifiable proximal lesions (either ACF or polyp), 14 subjects with at least 1 ACF but no polyp(s), and 15 subjects with both at least 1 ACF and a synchronous proximal polyp(s) detected at colonoscopy. Bacterial cells adherent to the epithelia of ACF and normal mucosa were visualized by in situ hybridization within confocal sections. Bacterial DNA isolated from biopsies was used to construct PCR amplicon libraries targeting the V4 hypervariable region of the 16S rRNA gene, which were then sequenced on the Illumina platform. ACF showed significantly greater heterogeneity in their bacterial profiles compared to normal mucosa. Interestingly, one of the bacterial community structures we characterized was strongly correlated with the presence of synchronous polyps. The observed dysbiosis is more prominent within the colonic epithelium that also harbors synchronous polyps. Finally using DNA-mass spectrometry to evaluate a panel of colorectal cancer hot-spot mutations present in the ACF, we found that several APC gene mutations (R1450*, R876*, S1465fs*3) were positively associated with the presence of Instestinibacter sp., whereas KRAS mutations (G12V, G12D) were positively correlated with Ruminococcus gnavus. This result indicates a potential relationship between specific colon-associated bacterial species and somatically acquired CRC-related mutations. Overall, our findings suggest that perturbations to the normal adherent mucosal flora may constitute a risk factor for early neoplasia, demonstrating the potential impact of mucosal dysbiosis on the tissue microenvironment and behavior of ACF that may facilitate (or impede) their progression towards more advanced forms of neoplasia.

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Characterization of Mucosal Dysbiosis of Early Colonic Neoplasia

npj Precision Oncology ◽

10.1038/s41698-019-0101-6 ◽

2019 ◽

Vol 3 (1) ◽

Cited By ~ 1

Author(s):

Bo-young Hong ◽

Takayasu Ideta ◽

Bruno S. Lemos ◽

Yuichi Igarashi ◽

Yuliana Tan ◽

...

Keyword(s):

Bacterial Species ◽

Tumor Development ◽

Gene Mutations ◽

Normal Mucosa ◽

Proximal Colon ◽

Aberrant Crypt Foci ◽

Bacterial Cells ◽

High Definition ◽

Bacterial Microbiome ◽

Synchronous Polyps

AbstractAberrant crypt foci (ACF) are the earliest morphologically identifiable lesions in the colon that can be detected by high-definition chromoendoscopy with contrast dye spray. Although frequently associated with synchronous adenomas, their role in colorectal tumor development, particularly in the proximal colon, is still not clear. The goal of this study was to evaluate the profile of colon-adherent bacteria associated with proximal ACF and to investigate their relationship to the presence and subtype of synchronous polyps present throughout the colon. Forty-five subjects undergoing a screening or surveillance colonoscopy were included in this retrospective study. Bacterial cells adherent to the epithelia of ACF and normal mucosal biopsies were visualized by in situ hybridization within confocal tissue sections. ACF showed significantly greater heterogeneity in their bacterial microbiome profiles compared with normal mucosa. One of the bacterial community structures we characterized was strongly correlated with the presence of synchronous polyps. Finally, using DNA mass spectrometry to evaluate a panel of colorectal cancer hotspot mutations present in the ACF, we found that three APC gene mutations were positively associated with the presence of Instestinibacter sp., whereas KRAS mutations were positively correlated with Ruminococcus gnavus. This result indicates a potential relationship between specific colon-associated bacterial species and somatically acquired CRC-related mutations. Overall, our findings suggest that perturbations to the normal adherent mucosal flora may constitute a risk factor for early neoplasia, demonstrating the potential impact of mucosal dysbiosis on the tissue microenvironment and behavior of ACF that may facilitate their progression towards more advanced forms of neoplasia.

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Genomics of the Uncultivated, Periodontitis-Associated BacteriumTannerellasp. BU045 (Oral Taxon 808)

mSystems ◽

10.1128/msystems.00018-18 ◽

2018 ◽

Vol 3 (3) ◽

Cited By ~ 6

Author(s):

Clifford J. Beall ◽

Alisha G. Campbell ◽

Ann L. Griffen ◽

Mircea Podar ◽

Eugene J. Leys

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Chronic Periodontitis ◽

Bacterial Species ◽

The United States ◽

Oral Microbiome ◽

Rrna Gene ◽

Bacterial Cells ◽

Data Set ◽

Content Type

ABSTRACTDespite decades of research into the human oral microbiome, many species remain uncultivated. The technique of single-cell whole-genome amplification and sequencing provides a means of deriving genome sequences for species that can be informative on biological function and suggest pathways to cultivation.Tannerella forsythiahas long been known to be highly associated with chronic periodontitis and to cause periodontitis-like symptoms in experimental animals, andTannerellasp. BU045 (human oral taxon 808) is an uncultivated relative of this organism. In this work, we extend our previous sequencing of theTannerellasp. BU063 (human oral taxon 286) genome by sequencing amplified genomes from 11 cells ofTannerellasp. BU045, including 3 genomes that are at least 90% complete.Tannerellasp. BU045 is more closely related toTannerellasp. BU063 than toT. forsythiaby gene content and average nucleotide identity. However, two independent data sets of association with periodontitis, one based on 16S rRNA gene abundance and the other based on gene expression in a metatranscriptomic data set, show thatTannerellasp. BU045 is more highly associated with disease thanTannerellasp. BU063. Comparative genomics shows genes and functions that are shared or unique to the different species, which may direct further research of the pathogenesis of chronic periodontitis.IMPORTANCEPeriodontitis (gum disease) affects 47% of adults over 30 in the United States (P. I. Eke, B. A. Dye, L. Wei, G. O. Thornton-Evans, R. J. Genco, et al., J Dent Res 91:914–920, 2012), and it cost between $39 and $396 billion worldwide in 2015 (A. J. Righolt, M. Jevdjevic, W. Marcenes, and S. Listl, J Dent Res, 17 January 2018, https://doi.org/10.1177/0022034517750572). Many bacteria associated with the disease are known only by the DNA sequence of their 16S rRNA gene. In this publication, amplification and sequencing of DNA from single bacterial cells are used to obtain nearly complete genomes ofTannerellasp. BU045, a species of bacteria that is more prevalent in patients with periodontitis than in healthy patients. Comparing the complete genome of this bacterium to genomes of related bacterial species will help to better understand periodontitis and may help to grow this organism in pure culture, which would allow a better understanding of its role in the mouth.

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Uncovering the hidden bacterial ghost communities of yeast and experimental evidences demonstrates yeast as thriving hub for bacteria

Scientific Reports ◽

10.1038/s41598-021-88658-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

B. Indu ◽

Tallapragada Keertana ◽

Sahu Ipsita ◽

Uppada Jagadeeshwari ◽

Chintalapati Sasikala ◽

...

Keyword(s):

Bacterial Species ◽

Model Organism ◽

Yeast Cells ◽

Rrna Gene ◽

Fish Analysis ◽

Bacterial Cells ◽

Introduced Fish ◽

Yeast Cultures ◽

As Species ◽

Bacterial Ghost

AbstractOur major concern was to address “yeast endobacteria” which was based on a few reports in the recent past where bacteria may find yeast as a niche for survival. In this study, we report the microbiota of twenty-nine axenic yeast cultures recovered from different habitats based on their 16S rRNA gene-amplicon metagenomes. Yeasts were identified based on D1/D2 or ITS gene sequences. Bacterial diversity was widespread, varied and rich among all yeasts except for four strains. Taxa belonging to the phylum Firmicutes, Proteobacteria, Actinobacteria and Bacteroidetes and the genera; Streptococcus, Propionibacterium were common to all the yeasts. Candida tropicalis was used as a model organism to confirm bacteria through fluorescence in situ hybridization (FISH), isolating and re-introducing the isolated bacteria into the yeast. FISH analysis confirmed the endobacteria of C. tropicalis and we have successfully isolated four bacteria only after lysis and disruption of yeast cells. These bacteria were identified as species of Pseudomonas, Chryseobacterium, Lysinibacillus and Propionibacterium. Guestimates indicate 95% of bacterial species of C. tropicalis are yet-to-be-cultivated. We have successfully reintroduced mCherry tagged Pseudomonas into C. tropicalis. Also, auto-fluorescent Prochlorococcus and Rhodopseudomonas could be introduced into C. tropicalis while mCherry tagged E. coli or Salmonella could not be introduced. FISH analysis confirmed the presence of both native and infected bacterial cells present in C. tropicalis. Our findings unveil the insights into the ghost microbiota associated with yeast, which otherwise are considered to be axenic cultures. Their inherent occurrence, together with co-cultivation experiments under laboratory conditions suggests that yeasts are a thriving hub for bacterial communities.

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Development of a PCR Assay for Detection of Enterobacteriaceae in Foods

Journal of Food Protection ◽

10.4315/0362-028x-66.10.1798 ◽

2003 ◽

Vol 66 (10) ◽

pp. 1798-1804 ◽

Cited By ~ 22

Author(s):

SHIGERU NAKANO ◽

TORU KOBAYASHI ◽

KENICHI FUNABIKI ◽

ATSUSHI MATSUMURA ◽

YASUHIRO NAGAO ◽

...

Keyword(s):

Salmonella Enteritidis ◽

Enrichment Culture ◽

Simple Procedure ◽

Bacterial Species ◽

Brain Heart Infusion ◽

Rrna Gene ◽

Bacterial Cells ◽

Bacterial Strains ◽

Pcr Assay ◽

Chelex 100

A broad-range PCR assay for the detection of bacteria belonging to the Enterobacteriaceae family was developed in this study. Primers targeting the bacterial 16S rRNA gene were newly designed and used in this PCR assay. To determine the specificity of the assay, 72 different bacterial species (of 49 genera), 2 fungi, 3 animals, and 4 plants were tested. Results were positive for every tested Vibrioaceae or Enterobacteriaceae strain except Proteus mirabilis. For all other bacterial strains and eukaryotes tested, results were negative. Bacterial DNA for PCR was prepared by a simple procedure with the use of Chelex 100 resin from culture after growth in brain heart infusion medium. To test this PCR assay for the monitoring of the Enterobacteriaceae family, either Escherichia coli or Salmonella Enteritidis was inoculated into various foods as an indicator. Prior to the PCR, the inoculation of 10 to 40 CFU of bacteria per g of food was followed by a 5-h enrichment culture step, and the PCR assay allowed the detection of bacterial cells. When actual examinations of the contamination of 15 noodle foods with Enterobacteriaceae by this PCR assay were conducted, 33% (5 of 15) of the samples tested positive. These results agreed with those of the Petri film Enterobacteriaceae Count Plate assay. Including the enrichment culture step, the entire PCR detection process can be completed within 7 h.

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DIVERSITY OF CULTURABLE BACTERIAL MICROBIOTA OF THE Eisenia foetida DIGESTIVE TRACT

Revista Fitotecnia Mexicana ◽

10.35196/rfm.2018.3.255-264 ◽

2018 ◽

Vol 41 (3) ◽

pp. 255-264 ◽

Cited By ~ 1

Author(s):

J. Abraham Pérez-Pérez ◽

David Espinosa-Victoria ◽

Hilda V. Silva-Rojas ◽

Lucía López-Reyes

Keyword(s):

Bacterial Diversity ◽

Digestive Tract ◽

Bacterial Species ◽

Brain Heart Infusion ◽

Rrna Gene ◽

Eisenia Foetida ◽

Bacterial Isolates ◽

Bacterial Microbiota ◽

Decomposition Of Organic Matter ◽

Earthworm Gut

Bacteria are an unavoidable component of the natural earthworm diet; thus, bacterial diversity in the earthworm gut is directly linked to decomposition of organic matter and development of the surrounding plants. The aim of this research was to isolate and to identify biochemically and molecularly the culturable bacterial microbiota of the digestive tract of Eisenia foetida. Earthworms were sourced from Instituto de Reconversión Productiva y Bioenergética (IRBIO) and Colegio de Postgraduados (COLPOS), México. Bacterial isolation was carried out on plates of Brain Heart Infusion (BHI) culture medium. Fifty six and 44 bacterial isolates were obtained from IRBIO and COLPOS, respectively. The population was composed of 44 Gram-negative and 56 Gram-positive isolates. Over 50 % of the bacterial isolates were rod-shaped cells. The 16S rRNA gene was sequenced and nine genera were identified in worms from IRBIO (Bacillus, Paenibacillus, Solibacillus, Staphylococcus, Arthrobacter, Pantoea, Stenotrophomonas, Acinetobacter and Aeromonas) and six in worms from COLPOS (Bacillus, Paenibacillus, Stenotrophomonas, Staphylococcus, Acinetobacter and Aeromonas). Bacillus was the predominant genus, with eight and six species in the oligochaetes from IRBIO and COLPOS, respectively. The most represented bacteria in the worms from both sites were Bacillus sp. and B. subtilis. The predominance of Bacillus was probably due to spore formation, a reproductive strategy that ensures survival and dispersion in the soil and oligochaetes digestive tract. The gut of E. foetida not only harbored bacterial species of agronomic importance but also species potentially pathogenic for humans (Staphylococcus warneri, Pantoea agglomerans and Stentrophomonas sp.). The larger bacterial diversity in worms from IRBIO could be due to their feeding on cattle manure, which is a rich source of bacteria.

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Modulation of Gut Microbiota through Dietary Phytochemicals as a Novel Anti-infective Strategy

Current Drug Discovery Technologies ◽

10.2174/1570163816666191107124214 ◽

2020 ◽

Vol 17 (4) ◽

pp. 498-506 ◽

Cited By ~ 2

Author(s):

Pavan K. Mujawdiya ◽

Suman Kapur

Keyword(s):

Microbial Community ◽

Quorum Sensing ◽

Population Density ◽

Gut Microbiota ◽

Biofilm Formation ◽

Chemical Interaction ◽

Bacterial Species ◽

Critical Role ◽

Bacterial Cells ◽

Gut Microbes

: Quorum Sensing (QS) is a phenomenon in which bacterial cells communicate with each other with the help of several low molecular weight compounds. QS is largely dependent on population density, and it triggers when the concentration of quorum sensing molecules accumulate in the environment and crosses a particular threshold. Once a certain population density is achieved and the concentration of molecules crosses a threshold, the bacterial cells show a collective behavior in response to various chemical stimuli referred to as “auto-inducers”. The QS signaling is crucial for several phenotypic characteristics responsible for bacterial survival such as motility, virulence, and biofilm formation. Biofilm formation is also responsible for making bacterial cells resistant to antibiotics. : The human gut is home to trillions of bacterial cells collectively called “gut microbiota” or “gut microbes”. Gut microbes are a consortium of more than 15,000 bacterial species and play a very crucial role in several body functions such as metabolism, development and maturation of the immune system, and the synthesis of several essential vitamins. Due to its critical role in shaping human survival and its modulating impact on body metabolisms, the gut microbial community has been referred to as “the forgotten organ” by O`Hara et al. (2006) [1]. Several studies have demonstrated that chemical interaction between the members of bacterial cells in the gut is responsible for shaping the overall microbial community. : Recent advances in phytochemical research have generated a lot of interest in finding new, effective, and safer alternatives to modern chemical-based medicines. In the context of antimicrobial research various plant extracts have been identified with Quorum Sensing Inhibitory (QSI) activities among bacterial cells. This review focuses on the mechanism of quorum sensing and quorum sensing inhibitors isolated from natural sources.

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Gut microbiota markers associated with obesity and overweight in Italian adults

Scientific Reports ◽

10.1038/s41598-021-84928-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Vanessa Palmas ◽

Silvia Pisanu ◽

Veronica Madau ◽

Emanuela Casula ◽

Andrea Deledda ◽

...

Keyword(s):

Gut Microbiota ◽

Relative Abundance ◽

Smoking Status ◽

16S Rrna Gene Sequencing ◽

Normal Weight ◽

Activity Level ◽

Rrna Gene ◽

Illumina Platform ◽

Obesity And Overweight ◽

Rrna Gene Sequencing

AbstractIn the present study, we characterized the distinctive signatures of the gut microbiota (GM) from overweight/obese patients (OB), and normal-weight controls (NW), both of Sardinian origin. Fecal bacterial composition of 46 OB patients (BMI = 36.6 ± 6.0; F/M = 40/6) was analyzed and compared to that of 46 NW subjects (BMI = 21.6 ± 2.1; F/M = 41/5), matched for sex, age and smoking status, by using 16S rRNA gene sequencing on MiSeq Illumina platform. The gut microbial community of OB patients exhibited a significant decrease in the relative abundance of several Bacteroidetes taxa (i.e. Flavobacteriaceae, Porphyromonadaceae, Sphingobacteriaceae, Flavobacterium, Rikenella spp., Pedobacter spp., Parabacteroides spp., Bacteroides spp.) when compared to NW; instead, several Firmicutes taxa were significantly increased in the same subjects (Lachnospiraceae, Gemellaceae, Paenibacillaceae, Streptococcaceae, Thermicanaceae, Gemella, Mitsuokella, Streptococcus, Acidaminococcus spp., Eubacterium spp., Ruminococcus spp., Megamonas spp., Streptococcus, Thermicanus, Megasphaera spp. and Veillonella spp.). Correlation analysis indicated that body fatness and waist circumference negatively correlated with Bacteroidetes taxa, while Firmicutes taxa positively correlated with body fat and negatively with muscle mass and/or physical activity level. Furthermore, the relative abundance of several bacterial taxa belonging to Enterobacteriaceae family, known to exhibit endotoxic activity, was increased in the OB group compared to NW. The results extend our knowledge on the GM profiles in Italian OB, identifying novel taxa linking obesity and intestine.

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Nanopore-Sequencing Characterization of the Gut Microbiota of Melolontha melolontha Larvae: Contribution to Protection against Entomopathogenic Nematodes?

Pathogens ◽

10.3390/pathogens10040396 ◽

2021 ◽

Vol 10 (4) ◽

pp. 396

Author(s):

Ewa Sajnaga ◽

Marcin Skowronek ◽

Agnieszka Kalwasińska ◽

Waldemar Kazimierczak ◽

Karolina Ferenc ◽

...

Keyword(s):

Gut Microbiota ◽

Entomopathogenic Nematodes ◽

Bacterial Species ◽

Antagonistic Activity ◽

Rrna Gene ◽

Nanopore Sequencing ◽

Bacterial Phyla ◽

Melolontha Melolontha

This study focused on the potential relationships between midgut microbiota of the common cockchafer Melolontha melolontha larvae and their resistance to entomopathogenic nematodes (EPN) infection. We investigated the bacterial community associated with control and unsusceptible EPN-exposed insects through nanopore sequencing of the 16S rRNA gene. Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes were the most abundant bacterial phyla within the complex and variable midgut microbiota of the wild M. melolontha larvae. The core microbiota was found to include 82 genera, which accounted for 3.4% of the total number of identified genera. The EPN-resistant larvae differed significantly from the control ones in the abundance of many genera belonging to the Actinomycetales, Rhizobiales, and Clostridiales orders. Additionally, the analysis of the microbiome networks revealed different sets of keystone midgut bacterial genera between these two groups of insects, indicating differences in the mutual interactions between bacteria. Finally, we detected Xenorhabdus and Photorhabdus as gut residents and various bacterial species exhibiting antagonistic activity against these entomopathogens. This study paves the way to further research aimed at unravelling the role of the host gut microbiota on the output of EPN infection, which may contribute to enhancement of the efficiency of nematodes used in eco-friendly pest management.

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A Combined Analysis of Gut and Skin Microbiota in Infants with Food Allergy and Atopic Dermatitis: A Pilot Study

Nutrients ◽

10.3390/nu13051682 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1682

Author(s):

Ewa Łoś-Rycharska ◽

Marcin Gołębiewski ◽

Marcin Sikora ◽

Tomasz Grzybowski ◽

Marta Gorzkiewicz ◽

...

Keyword(s):

Atopic Dermatitis ◽

Food Allergy ◽

Gut Microbiota ◽

Bacterial Species ◽

Rrna Gene ◽

Healthy Children ◽

Skin Microbiota ◽

Fecal Samples ◽

Healthy Infants ◽

Α Diversity

The gut microbiota in patients with food allergy, and the skin microbiota in atopic dermatitis patients differ from those of healthy people. We hypothesize that relationships may exist between gut and skin microbiota in patients with allergies. The aim of this study was to determine the possible relationship between gut and skin microbiota in patients with allergies, hence simultaneous analysis of the two compartments of microbiota was performed in infants with and without allergic symptoms. Fifty-nine infants with food allergy and/or atopic dermatitis and 28 healthy children were enrolled in the study. The skin and gut microbiota were evaluated using 16S rRNA gene amplicon sequencing. No significant differences in the α-diversity of dermal or fecal microbiota were observed between allergic and non-allergic infants; however, a significant relationship was found between bacterial community structure and allergy phenotypes, especially in the fecal samples. Certain clinical conditions were associated with characteristic bacterial taxa in the skin and gut microbiota. Positive correlations were found between skin and fecal samples in the abundance of Gemella among allergic infants, and Lactobacillus and Bacteroides among healthy infants. Although infants with allergies and healthy infants demonstrate microbiota with similar α-diversity, some differences in β-diversity and bacterial species abundance can be seen, which may depend on the phenotype of the allergy. For some organisms, their abundance in skin and feces samples may be correlated, and these correlations might serve as indicators of the host’s allergic state.

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Inocybe brijunica sp. nov., a New Ectomycorrhizal Fungus from Mediterranean Croatia Revealed by Morphology and Multilocus Phylogenetic Analysis

Journal of Fungi ◽

10.3390/jof7030199 ◽

2021 ◽

Vol 7 (3) ◽

pp. 199

Author(s):

Armin Mešić ◽

Danny Haelewaters ◽

Zdenko Tkalčec ◽

Jingyu Liu ◽

Ivana Kušan ◽

...

Keyword(s):

Rna Polymerase Ii ◽

National Park ◽

Hot Spot ◽

Phylogenetic Reconstruction ◽

Ectomycorrhizal Fungus ◽

Alkaline Solutions ◽

Rrna Gene ◽

28S Rrna ◽

Internal Transcribed Spacer Region ◽

Biogeographical Region

A new ectomycorrhizal species was discovered during the first survey of fungal diversity at Brijuni National Park (Croatia), which consists of 14 islands and islets. The National Park is located in the Mediterranean Biogeographical Region, a prominent climate change hot-spot. Inocybe brijunica sp. nov., from sect. Hysterices (Agaricales, Inocybaceae), is described based on morphology and multilocus phylogenetic data. The holotype collection was found at the edge between grassland and Quercus ilex forest with a few planted Pinus pinea trees, on Veli Brijun Island, the largest island of the archipelago. It is easily recognized by a conspicuous orange to orange–red–brown membranaceous surface layer located at or just above the basal part of the stipe. Other distinctive features of I. brijunica are the medium brown, radially fibrillose to rimose pileus; pale to medium brown stipe with fugacious cortina; relatively small, amygdaliform to phaseoliform, and smooth basidiospores, measuring ca. 6.5–9 × 4–5.5 µm; thick-walled, utriform, lageniform or fusiform pleurocystidia (lamprocystidia) with crystals and mostly not yellowing in alkaline solutions; cheilocystidia of two types (lamprocystidia and leptocystidia); and the presence of abundant caulocystidia only in the upper 2–3 mm of the stipe. Phylogenetic reconstruction of a concatenated dataset of the internal transcribed spacer region (ITS), the nuclear 28S rRNA gene (nrLSU), and the second largest subunit of RNA polymerase II (rpb2) resolved I. brijunica and I. glabripes as sister species.

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