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 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.
A Mycobacterium smegmatis transcriptional regulator, MSMEG_5850, and its ortholog in M. tuberculosis, rv0775 were annotated as putative TetR Family Transcriptional Regulators. Our previous study revealed MSMEG_5850 is involved in global transcriptional regulation in M. smegmatis and the presence of gene product supported the survival of bacteria during nutritional starvation. Phylogenetic analysis showed that MSMEG_5850 diverged early in comparison to its counterparts in virulent strains. Therefore, the expression pattern of MSMEG_5850 and its counterpart, rv0775, was compared during various in-vitro growth and stress conditions. Expression of MSMEG_5850 was induced under different environmental stresses while no change in expression was observed under mid-exponential and stationary phases. No expression of rv0775 was observed under any stress condition tested, while the gene was expressed during the mid-exponential phase that declined in the stationary phase. The effect of MSMEG_5850 on the survival of M. smegmatis under stress conditions and growth pattern was studied using wild type, knockout, and supplemented strain. Deletion of MSMEG_5850 resulted in altered colony morphology, biofilm/pellicle formation, and growth pattern of M. smegmatis. The survival rate of wild-type MSMEG_5850 was higher in comparison to knockout under different environmental stresses. Overall, this study suggested the role of MSMEG_5850 in the growth and adaptation/survival of M. smegmatis under stress conditions.
- MeSH
- Bacterial Proteins * genetics metabolism MeSH
- Biofilms growth & development MeSH
- Phylogeny MeSH
- Stress, Physiological * MeSH
- Microbial Viability MeSH
- Mycobacterium smegmatis * genetics growth & development physiology metabolism MeSH
- Gene Expression Regulation, Bacterial MeSH
- Transcription Factors * genetics metabolism MeSH
- Publication type
- Journal Article MeSH
Bats are the natural reservoirs for a variety of emerging and re-emerging viruses. Among them, rabies virus (genus Lyssavirus, family Rhabdoviridae) is one of the first and most emblematic described in these animals. Since its first description, several new bat lyssaviruses have been regularly identified. In addition to lyssaviruses, other bat rhabdoviruses have also been discovered, including members of the genera Vesiculovirus, Ledantevirus and, more recently, Alphanemrhavirus and Tupavirus. However, the family Rhabdoviridae is one of the most abundant and diverse viral families, with 434 officially recognized species, divided into 5 subfamilies and 56 different genera. The number of rhabdoviruses associated with bats is therefore probably higher than that currently available. In this study, we first developed and validated a combined nested RT-qPCR technique (pan-rhabdo RT-nqPCR) dedicated to the broad detection of animal rhabdoviruses. After validation, this technique was used for a large retrospective screening of archival bat samples (n = 1962), including blood (n = 816), brain (n = 723) and oral swab (n = 423). These samples were collected from various bat species over a 12-year period (2007-2019) in 9 different countries in Europe and Africa. A total of 23 samples (1.2%) from bat species Miniopterus schreibersii, Rhinolophus euryale and Rhinolophus ferrumequinum tested positive for rhabdovirus infection, including 17 (2.1%) blood and 6 (1.4%) oral swab samples, all collected from bats originating from the Mediterranean region. Complete virus genome sequences were obtained by next-generation sequencing for most of the positive samples. Molecular and phylogenetic analysis of these sequences demonstrated that the virus isolates, named Mediterranean bat virus (MBV), were closely related and represented a new species, Mediterranean vesiculovirus, within the genus Vesiculovirus. MBV was more specifically related to other bat vesiculoviruses previously described from China and North America, together clustering into a distinct group of bat viruses within this genus. Interestingly, our results suggest that MBV is widespread, at least in the western part of the Mediterranean region, where it circulates in the blood of several bat species. These results expand the host range and viral diversity of bat vesiculoviruses, and pave the way for further studies to determine the transmission route and dissemination dynamics of these viruses in bat colonies, as well as to assess their potential threat to public health.
- MeSH
- Chiroptera * virology MeSH
- Phylogeny MeSH
- Genome, Viral MeSH
- Rhabdoviridae Infections * veterinary epidemiology virology MeSH
- Real-Time Polymerase Chain Reaction MeSH
- Vesiculovirus * genetics isolation & purification classification MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Mediterranean Region MeSH
Halophilic bacteria are extremophiles that thrive in saline environment. Their ability to withstand such harsh conditions makes them an ideal choice for industrial applications such as lignocellulosic biomass degradation. In this study, a halophilic bacterium with the ability to produce extracellular cellulases and hemicellulases, designated as Nesterenkonia sp. CL21, was isolated from mangrove sediment in Tanjung Piai National Park, Malaysia. Thus far, studies on lignocellulolytic enzymes concerning bacterial species under this genus are limited. To gain a comprehensive understanding of its lignocellulose-degrading potential, the whole genome was sequenced using the Illumina NovaSeq 6000 platform. The genome of strain CL21 was assembled into 25 contigs with 3,744,449 bp and a 69.74% GC content and was predicted to contain 3,348 coding genes. Based on taxonomy analysis, strain CL21 shares 73.8 to 82.0% average nucleotide identity with its neighbouring species, below the 95% threshold, indicating its possible status as a distinct species in Nesterenkonia genus. Through in-depth genomic mining, a total of 81 carbohydrate-active enzymes were encoded. Among these, 24 encoded genes were identified to encompass diverse cellulases (GH3), xylanases (GH10, GH11, GH43, GH51, GH127 and CE4), mannanases (GH38 and GH106) and pectinases (PL1, PL9, and PL11). The production of lignocellulolytic enzymes was tested in the presence of several substrates. This study revealed that strain CL21 can produce a diverse array of enzymes which are active at different time points. By combining experimental data with genomic information, the ability of strain CL21 to produce lignocellulolytic enzymes has been elucidated, with potential applications in biorefinery industry.
- MeSH
- Bacterial Proteins genetics metabolism MeSH
- Cellulases genetics metabolism MeSH
- Phylogeny * MeSH
- Genome, Bacterial * MeSH
- Genomics * MeSH
- Geologic Sediments microbiology MeSH
- Glycoside Hydrolases * genetics metabolism MeSH
- Lignin * metabolism MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Whole Genome Sequencing MeSH
- Base Composition MeSH
- Publication type
- Journal Article MeSH
