16S rDNA Research Articles

Sodium Butyrate-Loaded Microspheres With Enhanced Bioavailability for Targeted Treatment of Intestinal Barrier Injury.

Intestinal barrier dysfunction is related to diseases such as inflammatory bowel disease (IBD) and severe acute pancreatitis (SAP). Butyrate and its derivatives (e.g., sodium butyrate (SB)) can alleviate gut inflammatory responses. Nevertheless, these substances usually cannot fully exert protective effects due to low bioavailability. This research aimed to offer microspheres for treating intestinal barrier injury. Sodium alginate solution is prepared to dissolve SB, followed by mixingwith chitosan (CS)-protocatechuic aldehyde (PA)/calcium chloride solution. The required CS-PA/calcium alginate/SB (CPC/SB) microspheres are formed in this manner. Subsequently, the therapeutic effects of CPC/SB microspheres on intestinal barrier injury through in vivo dextran sulfate sodium salt (DSS)-induced IBD and sodium taurocholate (STC)-induced SAP models is explored. Results: The CPC/SB microspheres exhibited excellent antioxidant properties. In vivo bioluminescence imaging experiment confirmed the microspheres effectively targeted the inflammatory gut in IBD. Further in vivo experimental results indicated the microspheres significantly repaired intestinal barrier damage, exerting protective effects in IBD and SAP. Additionally, 16S rDNA sequencing explained the microspheres can regulate the balance between harmful and beneficial bacteria (such as Alistipes, Odoribacter, and Rikenellaceae RC9). This study provides a possible synthetic strategy of microsphere carriers to serve as a potential therapeutic tool for intestinal barrier injury.

Description of a new Osedax (Annelida, Polychaeta, Siboglinidae) species colonizing cow bones in the South Atlantic Ocean

A new species of Osedax is described here using molecular and morphological data. It was found at the depth of 550 m off the Brazilian coast through experimental deployment of cow bones. Osedax nataliaesp. nov. is the second Osedax species from the Southwest Atlantic Ocean and had been previously reported as Osedax ‘BioSuOr-4’. Phylogenetic analysis of five concatenated genetic makers (28S rDNA, Histone H3, 18S rDNA, 16S rDNA, and cytochrome c oxidase I) placed Osedax nataliaesp. nov. within a well-supported Osedax Clade V, nested within a clade of Pacific Ocean Osedax though with poor support. The minimum interspecific COI distance between O. nataliaesp. nov. and another known Osedax was 13.92% (closest to O. ‘sagami-3’). The maximum intraspecific COI diversity (uncorrected) within O. nataliaesp. nov. sampled here was 2.44% and population structure was visualized via haplotype network analysis. Morphologically, O. nataliaesp. nov. is characterized by its reddish orange crown of palps and a ventral yellowish collar on the anterior trunk where it meets the base of the crown. Osedax nataliaesp. nov. shares features with other Clade V species, notably pinnules inserted on the outer margin of palps. Additionally, the presence of dwarf males within the tube lumen of females was documented. Further sampling and research in the Southern Hemisphere are needed to understand the diversity and biogeography of Osedax across the world’s oceans.

Molecular identification of whole squids and calamari at fairs and markets in regions of Latin America

The commercial importance of cephalopods has increased considerably, being an important fishing resource. However, during the preparation for commercialization of those species, they suffer the process known as “finning” which includes removing and separating the head, arm, skin or even having the body structure cut into rings, which ends up making it difficult or often prevents the identification of the species, which can lead to replacements. In this sense, the present study aimed to use the large ribosomal region, rrnL (16S rDNA) to genetically identify cephalopod species sold in markets and fairs in Latin America. Whole and processed samples were collected from supermarkets and directly from local fishers the approximate collection location. Each generated sequence was submitted to the blastn portal for molecular comparison and included in the database for subsequent genetic identification. Our results indicate labeling errors in samples from the State of Pará that contained the species Dosidicus gigas found only in the Pacific Ocean and were generically labeled as “National Lula”. No type of substitution was found among the samples that were being sold at fairs and markets, only labeling errors. Thus, our results demonstrate the effectiveness of the rrnL for identifying species and evaluating labeling errors.

Mining, Identification, and Fermentation Optimization of Chitin Deacetylase from a Novel Strain Enterobacter sp. ZCDA27.

Chitin, a natural organic compound with content slightly lower than cellulose, is also known for chitosan, a substance derived from chitin through deacetylation. In this experiment, preliminary screening was conducted using the plate discoloration circle method, leading to the selection of a high-yield CDA-producing strain from 28 candidates through rescreening. Morphological characteristics and 16S rDNA sequence analysis revealed 99.93% homology with Enterobacter sichuanensis strain N24, thus naming this strain Enterobacter strain ZCDA27. Initial fermentation of the strain yielded CDA activity of 9.29 U/mL. Single-factor optimization was then performed, followed by a PB test to screen for significant factors affecting enzyme production. The response surface method was used to further optimize the fermentation conditions. The optimal fermentation conditions for the carbon source, nitrogen source, metal ion, fermentation temperature, time, liquid volume, and initial pH were explored. Significant factors affecting enzyme production, including MgSO4, initial medium pH, and fructose levels, were identified using the PB test. Finally, the fermentation conditions of ZCDA27 were optimized using the Box-Behnken design combined with RSM, which comprised fructose at 1.020%, magnesium sulfate at 0.016%, and peptone at 1%. The fermentation conditions included a temperature of 37, initial pH of 7.1, rotation speed of 140 × g, fermentation time of 28h, inoculation amount of 2%, and liquid volume of 40%. Under these conditions, the enzyme activity of ZCDA27 reached 14.52 U/mL, a 1.6-fold increase from the pre-optimization levels. In summary, this study provides an experimental foundation for further development and application of Enterobacter spp. ZCDA27 CDA.

Occurrence of Trichinella spiralis in farmed wild boars (Sus scrofa): an underrated risk in China.

Natural infection by Trichinella sp. has been reported in humans and more than 150 species of animals, especially carnivorous and omnivorous mammals. Although the presence of Trichinella sp. infection in wild boars (Sus scrofa) has been documented worldwide, limited information is known about Trichinella circulation in farmed wild boars in China. This study intends to investigate the prevalence of Trichinella sp. in farmed wild boars in China. Seven hundred and sixty-one (761) muscle samples from farmed wild boars were collected in Jilin Province of China from 2017 to 2020. The diaphragm muscles were examined by artificial digestion method. The overall prevalence of Trichinella in farmed wild boars was 0.53% [95% confidence interval (CI): 0.51–0.55]. The average parasite loading was 0.076 ± 0.025 larvae per gram (lpg), and the highest burden was 0.21 lpg in a wild boar from Fusong city. Trichinella spiralis was the only species identified by multiplex polymerase chain reaction. The 5S rDNA inter-genic spacer region of Trichinella was amplified and sequenced. The results showed that the obtained sequence (GenBank accession number: OQ725583) shared 100% identity with the T. spiralis HLJ isolate (GenBank accession number: MH289505). Since the consumption of farmed wild boars is expected to increase in the future, these findings highlight the significance of developing exclusive guidelines for the processing of slaughtered farmed wild boar meat in China.

Genetic Diversity Analysis and Polyploid Induction Identification of Idesia polycarpa

Idesia polycarpa from Sichuan is a valuable germplasm with high economic potential, but it faces variety scarcity. To address this, this study collected 16 varieties (lines), identifying IpHT1 as a promising parent due to its high oil content (38.5%) and red fruits. Polyploid induction via adding 0.50% colchicine to Murashige and Skoog (MS) medium yielded 520 IpHT1 mutagenized seedlings. Subsequently, flow cytometry (FCM) was performed on 401 morphologically variant seedlings which had been initially screened, resulting in the identification of 15 suspected triploids, 35 suspected tetraploids, and 3 chimeras. Furthermore, fluorescence in situ hybridization (FISH) analysis found that the probe (AG3T3)3 had terminal signals at both ends of each chromosome, allowing for the counting of 42 chromosomes in diploids and 84 in tetraploids. The probe 5S rDNA showed 2, 3, and 4 hybridization signals in the interphase nuclei of diploid, triploid, and tetraploid cells, respectively, but the probe (GAA)6 failed to produce any signal on I. polycarpa chromosomes. Ultimately, 18 polyploids were selected, including 7 triploids and 11 tetraploids. Triploids and tetraploids showed significant leaf morphological and physiological differences from diploids. Consequently, this study successfully established a polyploid breeding system for I. polycarpa, thereby enhancing its genetic diversity and breeding potential.

Isolation and in vitro investigation on lactic acid bacteria for potential probiotic properties from cat feces

BackgroundProbiotics, which are beneficial to the host, have been shown to benefit the health of cats. Lactic acid bacteria (LAB) are commonly used probiotics, but most strains used for cats are not derived from cats, leading to reduced efficacy and poor adaptation to cats. The objective was to identify LAB with promising probiotic potential specific to cats.MethodLABs were isolated from fecal samples of 20 healthy cats. Gram staining and the survival rate in the simulated gastrointestinal tract were used for preliminary screening. Candidate strains were identified by 16S rDNA sequencing, and further evaluated for adhesion ability, growth characteristics, antibacterial activity, antioxidant capacity, and safety.Results24 Gram-positive isolates were identified, with 10 (F1-F10) showing robust viability in the simulated gastroenteric fluid. These 10 strains exhibited excellent adhesion to Caco-2 cells and strong auto-agglutination properties. They also possessed the capacity to antagonize and aggregate pathogens (Staphylococcus aureus ATCC 25923, Salmonella Braenderup H9812, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa PAO1), Moreover, all strains demonstrated tolerance to H2O2 concentrations ranging from 0.5–2 mmol/L and the ability to scavenge 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radicals, indicating a certain level of antioxidant activity. Safety tests showed no hemolytic activity, and all but F6 were highly sensitive to antibiotics, with over 62.5% sensitivity to 16 antibiotics. Remarkably, F4 (Lactobacillus reuteri) and F10 (Lactobacillus brevis) exhibited exceptional viability in the simulated gastrointestinal tract, coupled with robust growth potential, enhanced adhesion efficiency, significant antibacterial and antioxidant properties.ConclusionOur findings revealed that F4 (Lactobacillus reuteri) and F10 (Lactobacillus brevis) hold promising potential as probiotics. This research lays a solid scientific foundation for the selection and application of probiotics tailored specifically for cats.

Metabolomic disorders caused by an imbalance in the gut microbiota are associated with central precocious puberty

BackgroundCentral precocious puberty (CPP) is characterized by the premature activation of the hypothalamic-pituitary-gonadal axis, resulting in early onset of sexual development. The incidence of CPP has been rising in recent years, with approximately 90% of cases lacking a clearly identifiable etiology. While an association between precocious puberty and gut microbiota has been observed, the precise causal pathways and underlying mechanisms remain poorly understood. The study aims to investigate the potential mechanisms through which gut microbiota imbalances may contribute to CPP.MethodsIn this study, clinical information and fecal samples were collected from 50 CPP patients and 50 healthy control subjects. The fecal samples were analyzed by 16S rDNA sequencing and UPLC−MS/MS metabolic analysis. Spearman correlation analysis was used to identify the relationships between gut microbiota and metabolites.ResultsThe gut microbiota composition in CPP patients was significantly different from that in healthy controls, characterized by an increased abundance of Faecalibacterium and a decreased abundance of Anaerotruncus. Additionally, significant differences were observed in metabolite composition between the CPP and control groups. A total of 51 differentially expressed metabolites were identified, with 32 showing significant upregulation and 19 showing significant downregulation in the CPP group. Furthermore, Spearman correlation analysis indicated that gut microbiota dysbiosis may contribute to altered metabolic patterns in CPP, given its involvement in the regulation of several metabolic pathways, including phenylalanine and tyrosine biosynthesis and metabolism, the citrate cycle (TCA cycle), glyoxylate and dicarboxylate metabolism, and tryptophan metabolism.ConclusionsThe study revealed the gut microbial and metabolite characteristics of CPP patients by integrating microbiome and metabolomics analyses. Moreover, several key metabolic pathways involved in the onset and progression of CPP were identified, which were regulated by gut microbiota. These findings broaden the current understanding of the complex interactions between gut microbial metabolites and CPP, and provide new insights into the pathogenesis and clinical management of CPP.

Phylogeography of Cold Water Soft Coral Alcyonium spp. (Anthozoa, Octocorallia: Alcyonacea) Between South America and the West Antarctic Peninsula.

The Antarctic marine environment has a unique geologic and climatic history that has contributed to the evolution of high species diversity. Given the current trend of environmental warming, understanding the history of Antarctic species is crucial for predicting the impact of climate change on ecosystem function. Soft corals are a group of striking presence in the benthic marine assemblages in the Southern Ocean, which is recognized as a biodiversity hotspot. DNA sequences (Cox1, mtMutS, and 28S rDNA) were utilized for molecular phylogenetic reconstructions, species delimitations, and divergence estimations to investigate the spatial patterns of genetic diversity in Alcyonium species in the southern South American-Antarctic region. Significant genetic divergence was observed between regions, with a clear genetic break between South America and the West Antarctic Peninsula and the identification of four putative species. Divergence time estimates indicated that Alcyonium's diversification began about 41.1 million years ago (Ma), coinciding with the opening of the Drake Passage and the formation of the Antarctic Circumpolar Current (ACC, ~42 Ma). This indicates that Alcyonium has persisted insitu for an extensive period, enduring a wide range of environmental conditions.

Helminth parasites of the invasive European brown hare (Lepus europaeus) in Brazil: the first report of Bunostomum trigonocephalum in a hare.

Invasive alien species have the potential to introduce pathogens of economic and health importance in new environments. In Brazil, parasites from the non-native European brown hare can be a threat to humans, domestic animals, and wildlife. Therefore, we aimed to describe the helminth fauna of the invasive European brown hare in three Brazilian states (São Paulo, Paraná, and Rio Grande do Sul). For this, 90 brown hares were collected and examined for helminths. Helminth specimens recovered were morphologically identified and genetically characterized based on the DNA of male specimens using three genetic regions (28S rDNA, ITS-2, and cox-1 mtDNA). Descriptors of infection were calculated, and statistical analysis was performed. Parasites were found only in the small intestine of 14.4% (13/90) of brown hares and low parasite loads per animal were recorded (range = 1-530). The obtained specimens were morphologically identified as Trichostrongylus colubriformis and Bunostomum trigonocephalum. There was a high level of agreement between phylogenetic analysis and morphology for T. colubriformis. The geographical region was the only significant factor for infection; the State of Rio Grande do Sul had a higher general prevalence, higher T. colubriformis specific prevalence, and higher mean abundance than the other states evaluated. All hares were in a good body condition. To our knowledge, this is a new host record for B. trigonocephalum. This is the first study on the helminthological diversity of European brown hares in Brazil, and our results indicate that their helminth fauna is represented by parasites of domestic ruminants with zoonotic potential.

Insight into the mechanism of alkyl polyglucose biosurfactants enhancing antibiotics resistance genes removal during biotransformation of waste activated sludge into medium-chain fatty acids

Enhancing the biodegradability of waste activated sludge (WAS) based on environmentally friendly biosurfactants alkyl polyglucose (APG) to promote the recovery of medium-chain fatty acids (MCFAs) is a promising strategy. However, the effect and underlying mechanism of APG on antibiotic resistance genes (ARGs) removal during MCFAs production by WAS anaerobic fermentation are still unclear. This study found that APG significantly enhanced the removal of ARGs during the anaerobic fermentation to produce MCFAs, and the maximum removal efficiency of total ARGs was 95.64 % in 0.3 g APG/g TSS group, which was 46.31 % higher than the control group. The increase in extracellular lactate dehydrogenase, 16S rDNA and ARGs indicated that APG strengthened the lysis of ARGs hosts, thus suppressing the vertical transfer of ARGs caused by host proliferation. Furthermore, APG facilitated the decline in the abundance of mobile gene elements and two-component system genes, which was beneficial to reduce the horizontal transfer of ARGs. Microbial community and network analysis revealed that APG enriched functional microorganism and reduced potential ARGs hosts. Finally, partial least-squares path model analysis further demonstrated that the effectiveness of APG in ARGs removal was related to the restriction of ARGs transfer and change of bacterial community.

Analysis of composition of gut microbial community in a rat model of functional dyspepsia treated with Simo Tang.

To investigate composition of gut microbial community in a rat model of functional dyspepsia (FD) and to explore the interventional effects of Simo Tang (, SMT). A rat model of FD was established through the tail-clamping stimulation method. The rat model of FD was assessed by the state of rats, their weight, sucrose preference rate, and intestinal propulsion rate. The DNA was extracted from stool samples after treatment with SMT. Amplified polymerase chain reaction (PCR) products of the 16S rDNA were sequenced using NovaseQ6000 after construction of libraries. Composition of gut microbial community in the stool samples was determined and analyzed by cluster analysis, bioinformatic analysis, and analysis of α-diversity and β-diversity. The rat model of FD was successfully established using the tail-clamping stimulation method. The statistical results of cluster analysis of operational taxonomic units (OTUs) showed that the relative abundance of OTUs in the FD group was the lowest, while it was the highest in the normal (N) group. The composition of microbiome in the four groups was similar at phyla level. Compared with the FD group, the abundance of Firmicutes was downregulated, and the abundance of Proteobacteria and Bacteroidetes was upregulated in the Simo Tang (SMT) and high-dose Simo Tang (SMT.G) groups. The ratio of Bacteroidetes/ Firmicutes was also elevated. According to the analysis of α-diversity and β-diversity, the abundance of flora in FD rats was significantly reduced. The treatment using SMT appeared beneficial to improve the diversity of flora. SMT could improve the intestinal flora in FD rats. The results showed that FD rats had intestinal flora imbalance, and species diversity increased. The results suggested that SMT could regulate the disorders of intestinal flora caused by FD. SMT could restore gut homeostasis and maintain gut flora diversity by modulating the gut microbiota and its associated metabolites in rats, thereby treating gastrointestinal diseases.

Comparative analysis of intestinal structure, enzyme activity, intestinal microbiota and gene expression in different segments of pufferfish (Takifugu Obscurus)

The structure of fish intestines does not have a clear regional division, while the function of the intestines may be related to their structure. Therefore, in this study, the delimitation of intestinal segments in pufferfish (Takifugu obscurus) was achieved by morphological analysis. Subsequently, enzyme activity, intestinal microbiota, and gene expression were examined to compare the differences among the pufferfish various segments. According to four morphological parameters: height of mucosa folds (HF), width of mucosa folds (WF), thickness of muscularis (TM), and cross-sectional area (CSA), the pufferfish's intestine was divided into anterior intestine (AI), middle intestine (MI), and posterior intestine (PI). The activity levels of amylase, lipase, and trypsin in the AI and MI were significantly higher than these in the PI. According to the analysis of 16S rDNA, the dominant microbiota at the phylum level in the different segments were Epsilonbacteraeota, Spirochaetes, and Proteobacteria. At the genus level, there were variations observed in the relative abundance of Brevinema, Mycobacterium, Bradyrhizobium, and Microvirga. α diversity analysis revealed that the richness indexes (Ace and Chao1) were the lowest in the MI, while β diversity analysis revealed significant difference in intestinal microbial community composition among the three intestinal segments. Furthermore, RNA-Seq was used to identify differential expression genes (DEGs) and biological pathways among the different intestinal segments. The DEGs between the AI and MI were enriched in pancreatic secretion and protein digestion and absorption, those between AI and PI were involved in ascorbate and aldarate metabolism and glutathione metabolism, and those between MI and PI were involved in steroid biosynthesis, fat digestion and absorption, vitamin digestion and absorption, and glycine, serine and threonine metabolism. In conclusion, the presented results compare and analyze the differences in various intestinal segments of pufferfish, which will be conductive to future exploration of the functions of these different segments.

Swimming combined with corn peptide counteracts high-fat diet-induced obesity through rescuing imbalanced gut flora

To investigate the effects of swimming and corn peptide on counteracting obesity of high-fat diet (HFD)-induced mice and uncover the underlying mechanisms through analyzing the compositions and structure of gut flora and corresponding metabolites, an obesity model was established using C57BL/6 mice with HFD feeding. The obese mice underwent swimming intervention, oral administration of corn peptide, or a combination of both interventions for 8 consecutive weeks. After the interventions, blood lipid levels were measured, and fecal samples were collected for 16S rDNA sequencing and broad-targeted metabolomics analysis. Metabolic pathway enrichment analysis was performed using the MetaboAnalyst software, and the correlations between differential phenotypes, gut flora, and metabolites were analyzed using the Spearman method. The combination of swimming and corn peptide interventions effectively reduced hyperlipidemia in obese mice. Swimming combined with corn peptide intervention partially reversed the dysbiosis of gut microbiota in obese mice. This included an increase in the relative abundance of beneficial bacteria such as Prevotellaceae and Oscillospiraceae, and a decrease in the relative abundance of Alloprevotella. Additionally, all three interventions improved four key metabolic pathways: glycerophospholipid metabolism, pyrimidine metabolism, tyrosine metabolism, and folate synthesis. Therefore, the combinatorial intervention of swimming and corn peptide can at least partially ameliorate HFD-induced gut microbiota dysbiosis and corresponding metabolic changes, promote energy metabolism, and contribute to body weight control and lipid-lowering effects in obese mice.

Effects of dechlorane plus on hepatic pathology, metabolic health and gut microbiota in male mice.

Dechlorane plus (DP), a widely used flame retardant, was added to Annex A of the Stockholm Convention on Persistent Organic Pollutants in 2023. This study aimed to investigate the effects of DP on glucose and lipid metabolism by orally exposing eight-week-old male mice to environmentally relevant concentrations of DP (0.5, 1, and 5mg/kg/day) for six weeks. The in vivo effects of DP on liver histomorphology, glucose and lipid metabolism, intestinal microbiota, and the associated molecular mechanisms were assessed. Pathological examination revealed that exposure to 1 and 5mg/kg/day DP induced hepatic damage, characterized by structural disarray of the hepatic cords and vacuolar degeneration of liver cells, while 0.5 and 1mg/kg/day DP exposure led to significant triglycerides (TG) accumulation in the liver. Metabolite analysis showed a marked increase in hepatic pyruvate, glycogen, and TG in mice exposed to 0.5 and 1mg/kg/day DP, while 5mg/kg/day exposure resulted in elevated glycogen levels and reduced pyruvate and glucose concentrations. The underlying mechanisms involved the transcriptional regulation of key enzymes related to glucose and lipid metabolism, as well as the activation of the PI3K/AKT pathway. Exposure to 5mg/kg/day DP upregulated genes associated with glycogenesis (GK), glycolysis (HK1 and PK), and fatty acid synthesis (SREBP1, FAS, and ACC1), while downregulating genes involved in gluconeogenesis (PCK1) and fatty acid β-oxidation (CPT1 and PPARA). The activated PI3K/AKT pathway regulated key proteins (GLUT4, GSK3β, and FoxO1), playing distinct roles in glucose and lipid metabolism. High-throughput 16S rDNA sequencing revealed that 5mg/kg/day DP exposure altered the composition and diversity of intestinal microbiota, reducing the relative abundance of beneficial probiotics at both the phylum and genus levels. These findings offer new insights into the complex mechanisms through which DP affects glucose and lipid metabolism in mammals, contributing to a more comprehensive evaluation of its toxicity.

Michigan winter wheat (Triticum aestivum L.) roots host communities of Mortierellaceae and endohyphal bacteria

Mortierellaceae are ecologically and economically important fungi implicated in soil health. However, the diversity and frequency of Mortierellaceae and their endobacteria in crop root systems is unclear. Roots of winter wheat were sampled using a randomized complete block design. Mortierellaceae were isolated, identified using ITS-LSU phylogenetic analysis, and 16S rDNA was screened for Burkholderia-related endobacteria (BRE) and Mollicutes-related endobacteria (MRE). A total of 102 root-associated Mortierellaceae were isolated from 217 wheat root samples. Linnemannia comprised 89% of isolates. BRE were detected in 12 isolates, while MRE were detected in only one isolate. Mortierellaceae frequency varied by cultivar and a weak trend towards cultivar specificity was observed. Together, these findings advance our understanding of BRE and MRE prevalence in fungi in agricultural soils. Further studies will be needed to determine how plant hosts recruit Mortierellaceae partners and factors that drive plant-Mortierellaceae interactions.

Katarium polorum n. sp., n. g., a novel thecofilosean amoeba (Cercozoa, Rhizaria) from the polar oceans.

Thecate amoebae play important roles in terrestrial and aquatic ecosystems. This study introduces a novel thecofilosean amoeba from Arctic and Antarctic sea sediments. Phylogenetic analysis based on the 18S rDNA sequence places it in the family Chlamydophryidae (order Tectofilosida, class Thecofilosea). However, the novel organism exhibits a significant genetic divergence and distinct morphology from its closest relatives, prompting us to erect the novel genus Katarium with its type species Katarium polorum. K. polorum is a consumer of diatoms and prokaryotes, indicating an important role in nutrient cycling in the polar marine food webs.

First report of Hepatozoon and Lankesterella spp. infections in wild rodents from Pakistan, and their potential impact on blood parameters and oxidative stress markers in vital organs.

Pakistan is home to a rich rodent fauna, yet no investigations have been conducted on the presence of Haemogregarines in these animals, leaving their epidemiology and genetic diversity in this subtropical region unexplored. In this study, blood samples from four wild rodent species, Rattus (R.) rattus (n = 122), Mus (M.) musculus (n = 64), Rattus norvegicus (n = 57), and Dryomys nitedula (n = 1), were collected between May 2022 and July 2023 from three districts in Punjab and three in Khyber Pakhtunkhwa. PCR targeting a fragment of 600 base pairs from the 18S rDNA gene revealed a 2.86% (7/244) prevalence of Haemogregarines in the rodents. DNA sequencing and BLAST analysis confirmed the presence of Hepatozoon spp. and Lankesterella spp. in the blood samples. Phylogenetic analysis indicated genetic diversity in the Pakistani sequences, which clustered with sequences found in reptiles, amphibians, birds, and mammals from various countries. The prevalence of the parasite varied among rodent species, with R. rattus showing the highest infection rate, followed by R. norvegicus and M. musculus. Female rodents were more frequently infected than males. Infected R. rattus exhibited significant disruptions in white blood cells, red blood cells, and platelet counts. Oxidative stress markers indicated elevated superoxide dismutase in the kidney, catalase in the heart, and malondialdehyde in the liver and lungs of infected rodents compared to uninfected ones. This study is an important contribution towards science as it the first report of Haemogregarines and Lankesterella spp. infections among Pakistani rodents.

Differences in the abundance and diversity of endosymbiotic bacteria drive host resistance of Philodromus cespitum, a dominant spider of central European orchards, to selected insecticides

The ability of tissue endosymbionts to degrade and detoxify agrochemicals is increasingly recognized as a mechanism supporting the survival of arthropods in agroecosystems. Therefore, tissue endosymbionts have the potential to drive insecticide resistance in agrobiont spiders, i.e., in major generalist predators and pest control agents within agroecosystems. We hypothesized that the abundance and diversity of the endosymbiotic bacteria of Philodromus cespitum, a philodromid spider dominating central European apple orchards, vary with regard to differences in predation capacity and drive host insecticide resistance. We provisioned P. cespitum with diets of varying protein and lipid content and topically exposed them to field-relevant doses of commonly used insecticides, namely Mospilan (acetamiprid), Movento (spirotetramat), Gondola (sulfoxaflor), Decis (deltamethrin), Coragen (chlorantraniliprole), and Benevia (cyantraniliprole). The analyses were based on 16S rDNA profiles from lysates of the cephalothorax and legs of the tested spiders. The application of Benevia, Mospilan, and Movento was partially lethal. The spiders that were resistant to the treatments with Benevia, Mospilan, or Movento were associated with the increased relative abundance of Mycoplasmatota by more than one order of magnitude. Additionally, the abundance of other bacteria differed in Mospilan-resistant and Mospilan-sensitive individuals. In contrast, the diet regimens were not associated with any major differences in the microbiome diversity nor the diversity of endosymbionts. Philodromus cespitum hosts assemblages with unexpectedly high beta diversity of endosymbionts. The OTU identified as the alpha proteobacterium endosymbiont of Coelostomidia zealandica was an obligate endosymbiont of the analyzed P. cespitum population. Wolbachia, Rickettsia, and Spiroplasma endosymbionts were also highly prevalent and differed in their responses to the applied treatments. In conclusion, differences in the abundance and diversity of endosymbiotic bacteria drove the resistance of the spider host to selected insecticides.

Investigation of gut microbiota composition in humans carrying blastocystis subtypes 1 and 2 and Entamoeba hartmanni

The composition of human gut microbiota is dominated by bacteria which have been extensively studied. The role of intestinal eukaryote microorganisms like Blastocystis, however, remains under investigation. Moreover, the potential impact on gut health related to Blastocystis presence was primarily investigated in symptomatic individuals mainly from industrialized countries, and appears to be mostly beneficial to the host microbiota. Data from surveys conducted in underdeveloped countries with higher prevalence and from asymptomatic individuals could therefore be valuable. The aim of this preliminary study was to analyze the composition of the gut microbiota in relation to the protozoa Blastocystis ST1 and ST2 and Entamoeba hartmanni carriage in asymptomatic subjects living in a semi-urban area of Côte d’Ivoire to add data into the ongoing debate on the role of Blastocystis in host health. The amplification of the V3 and V4 regions of bacterial 16S rDNA genes was performed to obtain the gut microbiota composition, and differential analyses on alpha and beta diversity were performed from the phylum to genus taxonomic level. The analysis revealed that individuals positive for both protozoa exhibited higher alpha and beta diversity compared to those who tested negative. Additionally, their bacterial composition showed a reduction in Bacteroides and an increase in Prevotella 9. Relative abundances of some OTUs, particularly Faecalibacterium, observed in individuals who tested positive for protozoa, were correlated with a good state of health of the gut microbiota. Blastocystis ST1 and ST2 associated with E. hartmanni thus appeared to be related to a state of intestinal eubiosis.