Tailocins are nano-scale phage tail-like protein complexes that can mediate antagonistic interactions between closely related bacterial species. While the capacity to produce R-type tailocin was found widely across Gammaproteobacteria, the production of F-type tailocins seems comparatively rare. In this study, we examined the freshwater isolate, Pragia fontium 24613, which can produce both R- and F-type tailocins. We investigated their inhibition spectrum, focusing on clinically relevant enterobacteria, and identified the associated tailocin gene cluster. Transmission electron microscopy confirmed that inactivation of the tape measure protein within the tailocin cluster disrupted R-tailocin production. Comparative analysis of Budviciaceae gene clusters showed high conservation of R-type tailocin genes, whereas F-type tailocin genes were found in only a few species, with little conservation. Our findings indicate a high prevalence of bacteriocin production among underexplored Enterobacteriales species. Detected tailocins showed potential as antimicrobials targeting clinically significant pathogens.
The diversity of cultivable endophytic fungi in native subshrubs of the Brazilian Cerrado is largely unknown. This study investigated the cultivable endophytic mycobiome of stems, leaves, and flowers of Peltaea polymorpha (Malvaceae). In total, 208 endophytic fungi were isolated, 95 from stems, 65 from leaves, and 48 from flowers. The isolates were classified as ascomycetes belonging to three classes, eight orders, ten families, 12 genera, and 31 species. Diaporthe, Nigrospora, and Colletotrichum were the dominant genera in the three analyzed organs. The richness estimators suggested that the number of species might be slightly higher than observed. The highest values for the Shannon and Simpson diversity indices were observed in stems. Beta diversity showed overlapping of fungal communities in different organs, with a high rate of sharing of taxa. Furthermore, the dominant primary fungal lifestyles were plant pathogens and saprobes. Our findings show that the cultivable endophytic fungal community of P. polymorpha is species-rich and that communities in different organs share genera and species.
- MeSH
- Ascomycota isolation & purification classification genetics MeSH
- Biodiversity * MeSH
- Endophytes * classification isolation & purification genetics growth & development MeSH
- Phylogeny MeSH
- Fungi * classification isolation & purification genetics growth & development MeSH
- Flowers microbiology MeSH
- Plant Leaves microbiology MeSH
- Mycobiome MeSH
- Grassland MeSH
- Plant Stems microbiology MeSH
- Tropical Climate MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Brazil MeSH
Worldwide prevalence of multi-antibiotic resistant bacteria is rapidly increasing, and the education of undergraduates and graduates about antibiotic resistance and its associated horizontal gene transfer is critical in the general effort to confront the spread of antibiotic resistance. In this study, a deeper understanding of antibiotic resistance and horizontal gene transfer was achieved by biomedical undergraduate students through a scientific research programme. The enthusiasm of students to participate in the training programme was very high, and results revealed that each student could identify the antibiotic resistance integrative and conjugative element from the Stenotrophomonas maltophilia MER1 genome. Each student could also draw the phylogenetic relationship of the antibiotic resistance integrative and conjugative element. In addition, students proved the horizontal transfer of antibiotic resistance genes from S. maltophilia MER1 to Escherichia coli strain 25DN through conjugation and PCR assays. Each group of students was able to obtain the expected results, indicating that the outcome of the scientific research programme was highly reproducible. This programme improved the theoretical knowledge about antibiotic resistance and horizontal gene transfer and the research skills of biomedical sciences students. Through this programme, students learned that antibiotic resistance genes can be horizontally transferred among different bacteria, laying a solid foundation for students to value the importance of the appropriate use of antibiotics in their future work and life.
- MeSH
- Anti-Bacterial Agents pharmacology MeSH
- Drug Resistance, Microbial * genetics MeSH
- Drug Resistance, Bacterial * genetics MeSH
- Biomedical Research * education MeSH
- Escherichia coli genetics drug effects MeSH
- Phylogeny MeSH
- Humans MeSH
- Gene Transfer, Horizontal * MeSH
- Students, Medical MeSH
- Students MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Endophytes are symbionts that live in healthy plants and potentially improve the health of plant holobionts. Here, we investigated the bacterial endophyte community of Citrus reticulata grown in the northern Persian Gulf. Bacteria were isolated seasonally from healthy trees (root, stem, bark, trunk, leaf, and crown tissues) in four regions of Hormozgan province (i.e., Ahmadi, Siyahoo, Sikhoran, Roudan), a subtropical hot region in Iran. A total of 742 strains from 17 taxa, 3 phyla, and 5 orders were found, most of which belonged to Actinobacteria (Actinobacteriales) as the dominant group, followed by Firmicutes (Bacillales), Proteobacteria (Sphingomonadales, Rhizobiales), and Cyanobacteria (Synechoccales). The genera included Altererythrobacter, Arthrobacter, Bacillus, Cellulosimicrobium, Curtobacterium, Kocuria, Kytococcus, Methylopila, Mycobacterium, Nocardioides, Okiabacterium, Paracraurococcus, and Psychrobacillus. The most frequently occurring species included Psychrobacillus psychrodurans, Kytococcus schroetri, and Bacillus cereus. In addition, the overall colonization frequency and variability of endophytes were higher on the trunks. The leaves showed the lowest species variability in all sampling periods. The frequency of endophyte colonization was also higher in summer. The Shannon-Wiener (H') and Simpson indices varied with all factors, i.e., region, season, and tissue type, with the maximum in Roudan. Furthermore, 52.9% of the strains were capable of nitrogen fixation, and 70% produced antagonistic hydrogen cyanide (HCN). Thus, C. reticulata harbors a variety of bioactive bacterial endophytes that could be beneficial for host fitness in such harsh environments.
- MeSH
- Bacteria * classification metabolism isolation & purification genetics MeSH
- Biodiversity MeSH
- Citrus * microbiology MeSH
- Endophytes * classification isolation & purification metabolism genetics MeSH
- Nitrogen Fixation * MeSH
- Phylogeny MeSH
- Plant Leaves microbiology MeSH
- Microbiota * MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Seasons MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Iran MeSH
The present study has undertaken the isolation of marine yeasts from mangrove sediment samples and their ability to produce alkaline protease enzymes. A total of 14 yeast isolates were recovered on yeast-malt agar (YMA) and yeast extract peptone dextrose (YEPD) agar medium. After screening for proteolytic activity on skim milk agar, marine yeast isolate, AKB-1 exhibited a hydrolysis zone of 18 mm. Optimal conditions for the enzyme production from yeast isolate AKB-1 were at 30 °C, pH 8, fructose as carbon source, potassium nitrate as nitrogen source, and 25% saline concentration. Under the optimal conditions, the protease enzyme activity of the isolate AKB-1 was observed to be 978 IU/mL. The structural and functional analysis was carried out through FTIR and HPLC analysis for the extracted protease enzyme. Furthermore, the enzyme produced was partially purified by solvent extraction using ethyl acetate and ammonium sulfate precipitation (3.4-fold) followed by dialysis (56.8-fold). The molecular weight of the purified enzyme was observed to be around 60 kDa using SDS-PAGE. The extracted protein showed good antibacterial activity against six different clinical bacterial pathogens and the highest against Bacillus cereus (16 ± 0.5 mm). The extracted protease enzyme was revealed to remove blood stains from cloth within 20 min of application similar to the commercial detergent. The marine yeast isolate was further identified as Candida orthopsilosis AKB-1 (Accession number KY348766) through 18S rRNA sequencing, and a phylogenetic tree was generated.
- MeSH
- Anti-Bacterial Agents pharmacology metabolism chemistry isolation & purification MeSH
- Bacillus cereus drug effects MeSH
- Bacterial Proteins * chemistry pharmacology metabolism isolation & purification MeSH
- Candida * enzymology isolation & purification genetics classification MeSH
- Endopeptidases * chemistry metabolism isolation & purification pharmacology MeSH
- Phylogeny MeSH
- Geologic Sediments microbiology MeSH
- Hydrogen-Ion Concentration MeSH
- Culture Media chemistry MeSH
- Microbial Sensitivity Tests MeSH
- Molecular Weight MeSH
- Enzyme Stability MeSH
- Temperature MeSH
- Publication type
- Journal Article MeSH
Yeasts are unicellular fungi that occur in a wide range of ecological niches, where they perform numerous functions. Furthermore, these microorganisms are used in industrial processes, food production, and bioremediation. Understanding the physiological and adaptive characteristics of yeasts is of great importance from ecological, biotechnological, and industrial perspectives. In this context, we evaluated the abilities to assimilate and ferment different carbon sources, to produce extracellular hydrolytic enzymes, and to tolerate salt stress, heavy metal stress, and UV-C radiation of two isolates of Eremothecium coryli, isolated from Momordica indica fruits. The two isolates were molecularly identified based on sequencing of the 18S-ITS1-5.8S-ITS2 region. Our isolates were able to assimilate nine carbon sources (dextrose, galactose, mannose, cellobiose, lactose, maltose, sucrose, melezitose, and pectin) and ferment three (glucose, maltose, and sucrose). The highest values of cellular dry weight were observed in the sugars maltose, sucrose, and melezitose. We observed the presence of hyphae and pseudohyphae in all assimilated carbon sources. The two isolates were also capable of producing amylase, catalase, pectinase, and proteases, with the highest values of enzymatic activity found in amylase. Furthermore, the two isolates were able to grow in media supplemented with copper, iron, manganese, nickel, and zinc and to tolerate saline stress in media supplemented with 5% NaCl. However, we observed a decrease in CFU at higher concentrations of these metals and NaCl. We also observed morphological changes in the presence of metals, which include changes in cell shape and cellular dimorphisms. The isolates were sensitive to UV-C radiation in the shortest exposure time (1 min). Our findings reinforce the importance of endophytic yeasts for biotechnological and industrial applications and also help to understand how these microorganisms respond to environmental variations caused by human activities.
- MeSH
- Endophytes * isolation & purification genetics metabolism physiology classification radiation effects MeSH
- Fermentation MeSH
- Phylogeny MeSH
- Stress, Physiological * MeSH
- Carbohydrate Metabolism * MeSH
- Fruit * microbiology MeSH
- Saccharomycetales * isolation & purification genetics physiology metabolism radiation effects classification MeSH
- Metals, Heavy toxicity MeSH
- Ultraviolet Rays MeSH
- Publication type
- Journal Article MeSH
The isolation and study of fungi within specific contexts yield valuable insights into the intricate relationships between fungi and ecosystems. Unlike culture-independent approaches, cultivation methods are advantageous in this context because they provide standardized replicates, specific species isolation, and easy sampling. This study aimed to understand the ecological process using a microcosm system with pesticide concentrations similar to those found in the soil, in contrast to high doses, from the isolation of the enriched community. The atrazine concentrations used were 0.02 mg/kg (control treatment), 300 ng/kg (treatment 1), and 3000 ng/kg (treatment 2), using a 28-day microcosm system. Ultimately, the isolation resulted in 561 fungi classified into 76 morphospecies. The Ascomycota phylum was prevalent, with Purpureocillium, Aspergillus, and Trichoderma being consistently isolated, denoting robust and persistent genera. Diversity analyses showed that the control microcosms displayed more distinct fungal morphospecies, suggesting the influence of atrazine on fungal communities. Treatment 2 (higher atrazine concentration) showed a structure comparable to that of the control, whereas treatment 1 (lower atrazine concentration) differed significantly, indicating that atrazine concentration impacted community variance. Higher atrazine addition subtly altered ligninolytic fungal community dynamics, implying its potential for pesticide degradation. Finally, variations in atrazine concentrations triggered diverse community responses over time, shedding light on fungal resilience and adaptive strategies against pesticides.
- MeSH
- Atrazine * metabolism pharmacology MeSH
- Biodegradation, Environmental MeSH
- Phylogeny MeSH
- Herbicides * metabolism MeSH
- Fungi * classification isolation & purification metabolism drug effects genetics growth & development MeSH
- Soil Pollutants metabolism MeSH
- Mycobiome * drug effects MeSH
- Soil Microbiology MeSH
- Publication type
- Journal Article MeSH
A novel Gram-stain-negative, strictly aerobic, rod-shaped, light-yellow-pigmented, and chemo-organoheterotrophic bacterium, designated DF-77T, was isolated from dense mats of filamentous algae collected in March 2004 at Okinawa in Japan. The microorganism grew at 0-2.0% NaCl concentrations (w/v), pH 6.0-9.0, and 20-30 °C. The 16S rRNA gene sequence-based phylogenetic tree demonstrated that the strain DF-77T is a novel member of the family Flavobacteriaceae and was greatly related to Flagellimonas nanhaiensis SM1704T with sequence similarity of 95.5%. The main fatty acids were iso-C15:1 G, iso-C15:0, and iso-C17:0 3-OH, and the only isoprenoid quinone was menaquinone-6. The dominant polar lipids were phosphatidylethanolamine, two unidentified aminolipids, an unidentified phosphoaminolipid, and four unidentified lipids. The genome size of strain DF-77T was 3.60 Mbp with a DNA G + C content of 47.5%. The average nucleotide identity (ANI) value between the genomes of strain DF-77T and its closely related species was 69.8-70.7%. The digital DNA - DNA hybridization (dDDH) value of strain DF-77T with the strain of F. nanhaiensis SM1704T was 16.8%. The genome of the strain DF-77T revealed that it encoded several genes involved in bio-macromolecule degradation, indicating a high potential for producing industrially useful enzymes. Consequently, the strain is described as a new species in the genus Flagellimonas, for which the name Flagellimonas algarum sp. nov., is proposed with the type strain DF-77T (= KCTC 72791T = NBRC 114251T).
- MeSH
- DNA, Bacterial genetics chemistry MeSH
- Flavobacteriaceae * classification isolation & purification genetics MeSH
- Phospholipids analysis MeSH
- Phylogeny MeSH
- Genome, Bacterial MeSH
- Nucleic Acid Hybridization MeSH
- Fatty Acids analysis MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Bacterial Typing Techniques MeSH
- Vitamin K 2 analysis analogs & derivatives MeSH
- Base Composition MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Japan MeSH
In this study, lactic acid bacteria (LAB) isolation from fermented foods and molecular identification using magnetic bead technology were performed. And then exopolysaccharide (EPS) production possibility was tested in agar medium, and the positive ones were selected for the next step. The bacteria that could produce higher carbohydrate level were grown in MRS medium fortified with whey and pumpkin waste. In our study, 19 different LAB species were identified from fermented products collected from different places in Hatay (Türkiye) province. In molecular identification, universal primer pairs, p806R/p8FPL, and PEU7/DG74 were used for PCR amplification. After that, PCR products purified using paramagnetic bead technology were sequenced by the Sanger sequencing method. The dominant species, 23.8% of the isolates, were identified as Lactiplantibacillus plantarum. As a technological property of LAB, exopolysaccharide production capability of forty-two LAB isolate was tested in agar medium, and after eleven isolates were selected as positive. Two LAB (Latilactobacillus curvatus SHA2-3B and Loigolactobacillus coryniformis SHA6-3B) had higher EPS production capability when they were grown in MRS broth fortified with pumpkin waste and whey. The highest EPS content (1750 mg/L glucose equivalent) was determined in Loigolactobacillus coryniformis SHA6-3B grown in MRS broth fortified with 10% pumpkin waste. Besides the produced EPS samples were validated with FTIR and SEM methods.
- MeSH
- Polysaccharides, Bacterial * biosynthesis metabolism MeSH
- Cucurbita microbiology MeSH
- Fermentation MeSH
- Fermented Foods * microbiology MeSH
- Phylogeny MeSH
- Culture Media chemistry MeSH
- Lactobacillales * isolation & purification classification genetics metabolism MeSH
- Waste Products * analysis MeSH
- Food Microbiology * MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Whey MeSH
- Publication type
- Journal Article MeSH
Euglenids have long been studied due to their unique physiology and versatile metabolism, providing underpinnings for much of our understanding of photosynthesis and biochemistry, and a growing opportunity in biotechnology. Until recently there has been a lack of genetic studies due to their large and complex genomes, but recently new technologies have begun to unveil their genetic capabilities. Whilst much research has focused on the model organism Euglena gracilis, other members of the euglenids have now started to receive due attention. Currently only poor nuclear genome assemblies of E. gracilis and Rhabdomonas costata are available, but there are many more plastid genome sequences and an increasing number of transcriptomes. As more assemblies become available, there are great opportunities to understand the fundamental biology of these organisms and to exploit them for biotechnology.
