Flagellimonas halotolerans sp. nov., a novel bacterium isolated from the South China Sea.

Two Gram-stain-negative strains, designed SYSU M86414T and SYSU M84420, were isolated from marine sediment samples of the South China Sea (Sansha City, Hainan Province, PR China). These strains were aerobic and could grow at pH 6.0-8.0 (optimum, pH 7.0), 4-37 °C (optimum, 28 °C), and in the presence of 0-10 % NaCl (w/v; optimum 3 %). The predominant respiratory menaquinone of strains SYSU M86414T and SYSU M84420 was MK-6. The primary cellular polar lipid was phosphatidylethanolamine. The major cellular fatty acids (>10 %) in both strains were iso-C15 : 0, iso-C15 : 1 G, and iso-C17 : 0 3-OH. The DNA G+C content of strains SYSU M86414T and SYSU M84420 were both 42.10 mol%. Phylogenetic analyses based on 16S rRNA gene sequences and core genes indicated that these novel strains belonged to the genus Flagellimonas and strain SYSU M86414T showed the highest 16S rRNA gene sequence similarity to Flagellimonas marinaquae JCM 11811T (98.83 %), followed by Flagellimonas aurea BC31-1-A7T (98.62 %), while strain SYSU M84420 had highest 16S rRNA gene sequence similarity to F. marinaquae JCM 11811T (98.76 %) and F. aurea BC31-1-A7T (98.55 %). Based on the results of polyphasic analyses, strains SYSU M86414T and SYSU M84420 should be considered to represent a novel species of the genus Flagellimonas, for which the name Flagellimonas halotolerans sp. nov. is proposed. The type strain of the proposed novel isolate is SYSU M86414T (=GDMCC 1.3806T=KCTC 102040T).

Desertivirga arenae gen. nov., sp. nov. and Desertivirga brevis sp. nov., isolated from desert soil, and reclassification of Pedobacter xinjiangensis as Desertivirga xinjiangensis comb. nov. and Pedobacter mongoliensis as Paradesertivirga mongoliensis gen.nov., comb. nov.

Two novel bacterial strains, designated as SYSU D00823T and SYSU D00873T, were isolated from sandy soil of the Gurbantunggut Desert in Xinjiang, north-west China. SYSU D00823T and SYSU D00873T shared 99.0 % 16S rRNA gene sequence identity, and were both most closely related to Pedobacter xinjiangensis 12157T with 96.1 % and 96.0 % similarities, respectively. Phylogenetic and phylogenomic analyses revealed that the two isolates and P. xinjiangensis 12157T formed a separate distinct cluster in a stable subclade with the nearby species Pedobacter mongoliensis 1-32T, as well as the genera Pararcticibacter and Arcticibacter. Furthermore, P. mongoliensis 1-32T formed a separate deep-branching lineage and did not form a cluster with members of the genus Pedobacter. The average nucleotide identity and digital DNA-DNA hybridization values between SYSU D00823T and SYSU D00873T and related species were well below the thresholds for species delineation (<81.0 % and <24.0 %, respectively). The genomes of SYSU D00823T and SYSU D00873T were 6.19 and 6.43 Mbp in size with 40.4 % and 40.5 % DNA G+C contents, respectively. The predominant fatty acids (>10 %) of SYSU D00823T and SYSU D00873T were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c). Menaquinone-7 was the only respiratory quinone. The major polar lipids were phosphatidylethanolamine, glycosphingolipid, aminoglycolipid/glycolipid, aminophospholipid and three or four unidentified polar lipids. These data indicated that strains SYSU D00823T and SYSU D00873T should be assigned to two novel species of a new genus within the family Sphingobacteriaceae, for which the names Desertivirga arenae gen. nov., sp. nov. and Desertivirga brevis sp. nov. are proposed. The type strains are SYSU D00823T (=CGMCC 1.18630T=MCCC 1K04973T=KCTC 82278T) and SYSU D00873T (=CGMCC 1.18629T=MCCC 1K04974T=KCTC 82281T), respectively. Accordingly, the reclassification of P. xinjiangensis as Desertivirga xinjiangensis comb. nov., and P. mongoliensis as Paradesertivirga mongoliensis gen. nov., comb. nov. are also proposed.

Deciphering the pathogenic risks of microplastics as emerging particulate organic matter in aquatic ecosystem.

Microplastics are accumulating rapidly in aquatic ecosystems, providing habitats for pathogens and vectors for antibiotic resistance genes (ARGs), potentially increasing pathogenic risks. However, few studies have considered microplastics as particulate organic matter (POM) to elucidate their pathogenic risks and underlying mechanisms. Here, we performed microcosm experiments with microplastics and natural POM (leaves, algae, soil), thoroughly investigating their distinct effects on the community compositions, functional profiles, opportunistic pathogens, and ARGs in Particle-Associated (PA) and Free-Living (FL) bacterial communities. We found that both microplastics and leaves have comparable impacts on microbial community structures and functions, enriching opportunistic pathogens and ARGs, which may pose potential environmental risks. These effects are likely driven by their influences on water properties, including dissolved organic carbon, nitrate, DO, and pH. However, microplastics uniquely promoted pathogens as keystone species and further amplified their capacity as hosts for ARGs, potentially posing a higher pathogenic risk than natural POM. Our research also emphasized the importance of considering both PA and FL bacteria when assessing microplastic impacts, as they exhibited different responses. Overall, our study elucidates the role and underlying mechanism of microplastics as an emerging POM in intensifying pathogenic risks of aquatic ecosystems in comparison with conventional natural POM.

Methylobacterium nigriterrae sp. nov., isolated from black soil.

An aerobic, Gram-stain-negative, motile rod bacterium, designated as SYSU BS000021T, was isolated from a black soil sample in Harbin, Heilongjiang province, China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the genus Methylobacterium, and showed the highest sequence similarity to Methylobacterium segetis KCTC 62267 T (98.51%) and Methylobacterium oxalidis DSM 24028 T (97.79%). Growth occurred at 20-37℃ (optimum, 28 °C), pH 6.0-8.0 (optimum, pH 7.0) and in the presence of 0% (w/v) NaCl. Polar lipids comprised of phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified aminolipid and one unidentified polar lipid. The major cellular fatty acids (> 5%) were C18:0 and C18:1 ω7c and/or C18:1 ω6c. The predominant respiratory quinone was Q-10. The genomic G + C content was 68.36% based on the whole genome analysis. The average nucleotide identity (≤ 83.5%) and digital DNA-DNA hybridization (≤ 27.3%) values between strain SYSU BS000021T and other members of the genus Methylobacterium were all lower than the threshold values recommended for distinguishing novel prokaryotic species. Based on the results of phenotypic, chemotaxonomic and phylogenetic analyses, strain SYSU BS000021T represents a novel species of the genus Methylobacterium, for which the name Methylobacterium nigriterrae sp. nov. is proposed. The type strain of the proposed novel species is SYSU BS000021T (= GDMCC 1.3814 T = KCTC 8051 T).

Two Novel Alkaliphilic Species Isolated from Saline-Alkali Soil in China: Halalkalibacter flavus sp. nov., and Halalkalibacter lacteus sp. nov.

The degradation of farmland in China underscores the need for developing and utilizing saline-alkali soil. Soil health relies on microbial activity, which aids in the restoration of the land's ecosystem, and hence it is important to understand microbial diversity. In the present study, two Gram-stain-positive strains HR 1-10T and J-A-003T were isolated from saline-alkali soil. Preliminary analysis suggested that these strains could be a novel species. Therefore, the taxonomic positions of these strains were evaluated using polyphasic analysis. Phylogenetic and 16S rRNA gene sequence analysis indicated that these strains should be assigned to the genus Halalkalibacter. Cell wall contained meso-2,6-diaminopimelic acid. The polar lipids present in both strains were diphosphatidyl-glycerol, phosphatidylglycerol, and an unidentified phospholipid. The major fatty acids (>10%) were anteiso-C15:0, C16:0 and iso-C15:0. Average nucleotide identity and digital DNA#x2013;DNA hybridization values were below the threshold values (95% and 70%, respectively) for species delineation. Based on the above results, the strains represent two novel species of the genus Halalkalibacter, for which the names Halalkalibacter flavus sp. nov., and Halalkalibacter lacteus sp. nov., are proposed. The type strains are HR 1-10T (=GDMCC 1.2946T = MCCC 1K08312T = JCM 36285T), and J-A-003T (=GDMCC 1.2949T = MCCC 1K08417T = JCM 36286T).

Response of microbial diversity and function to the degradation of Barkol Saline Lake.

Barkol Lake, a shrinking hypersaline lake situated in the northeast of Xinjiang, China, has experienced the exposure of its riverbed and the gradual drying up of its original sediment due to climate change and human activities, resulting in the formation of alkaline soils. These changes have correspondingly altered the physicochemical characteristics of the surrounding environment. Microorganisms play a crucial role, with special functioning involved in various nutrient cycling and energy transfer in saline lake environments. However, little is known about how the microbial community dynamics and metabolic functions in this shrinking saline lake relate to the degradation process. To address this knowledge gap, a cultivation-independent method of amplicon sequencing was used to identify and analyze the microbial community and its potential ecological functions in the sediment and degraded area. The microbial community diversity was found to be significantly lower in the degraded areas than in the sediment samples. The Pseudomonadota was dominant in Barkol Saline Lake. The abundance of Desulfobacterota and Bacillota in the degraded areas was lower than in the lake sediment, while Pseudomonadota, Acidobacteriota, and Actinobacteriota showed an opposite trend. The ßNTI showed that microbial community assembly was primarily associated with deterministic processes in Barkol Saline Lake ecosystems and stochastic processes at the boundary between sediment and degraded areas. Functional predictions showed that sulfur metabolism, particularly sulfate respiration, was much higher in sediment samples than in the degraded areas. Overall, these findings provided a possible perspective for us to understand how microorganisms adapt to extreme environments and their role in saline lakes under environmental change.

Desloratadine ameliorates paclitaxel-induced peripheral neuropathy and hypersensitivity reactions in mice.

Paclitaxel (PTX) serves as a primary chemotherapy agent against diverse solid tumors including breast cancer, lung cancer, head and neck cancer and ovarian cancer, having severe adverse effects including PTX-induced peripheral neuropathy (PIPN) and hypersensitivity reactions (HSR). A recommended anti-allergic agent diphenhydramine (DIP) has been used to alleviate PTX-induced HSR. Desloratadine (DLT) is a third generation of histamine H1 receptor antagonist, but also acted as a selective antagonist of 5HTR2A. In this study we investigated whether DLT ameliorated PIPN-like symptoms in mice and the underlying mechanisms. PIPN was induced in male mice by injection of PTX (4 mg/kg, i.p.) every other day for 4 times. The mice exhibited 50% reduction in mechanical threshold, paw thermal response latency and paw cold response latency compared with control mice. PIPN mice were treated with DLT (10, 20 mg/kg, i.p.) 30 min before each PTX administration in the phase of establishing PIPN mice model and then administered daily for 4 weeks after the model was established. We showed that DLT administration dose-dependently elevated the mechanical, thermal and cold pain thresholds in PIPN mice, whereas administration of DIP (10 mg/kg, i.p.) had no ameliorative effects on PIPN-like symptoms. We found that the expression of 5HTR2A was selectively elevated in the activated spinal astrocytes of PIPN mice. Spinal cord-specific 5HTR2A knockdown by intrathecal injection of AAV9-5Htr2a-shRNA significantly alleviated the mechanical hyperalgesia, thermal and cold hypersensitivity in PIPN mice, while administration of DLT (20 mg/kg) did not further ameliorate PIPN-like symptoms. We demonstrated that DLT administration alleviated dorsal root ganglion neuronal damage and suppressed sciatic nerve destruction, spinal neuron apoptosis and neuroinflammation in the spinal cord of PIPN mice. Furthermore, we revealed that DLT administration suppressed astrocytic neuroinflammation via the 5HTR2A/c-Fos/NLRP3 pathway and blocked astrocyte-neuron crosstalk by targeting 5HTR2A. We conclude that spinal 5HTR2A inhibition holds promise as a therapeutic approach for PIPN and we emphasize the potential of DLT as a dual-functional agent in ameliorating PTX-induced both PIPN and HSR in chemotherapy. In summary, we determined that spinal 5HTR2A was selectively activated in PIPN mice and DLT could ameliorate the PTX-induced both PIPN- and HSR-like pathologies in mice. DLT alleviated the damages of DRG neurons and sciatic nerves, while restrained spinal neuronal apoptosis and CGRP release in PIPN mice. The underlying mechanisms were intensively investigated by assay against the PIPN mice with 5HTR2A-specific knockdown in the spinal cord by injection of adeno-associated virus 9 (AAV9)-5Htr2a-shRNA. DLT inhibited astrocytic NLRP3 inflammasome activation-mediated spinal neuronal damage through 5HTR2A/c-FOS pathway. Our findings have supported that spinal 5HTR2A inhibition shows promise as a therapeutic strategy for PIPN and highlighted the potential advantage of DLT as a dual-functional agent in preventing against PTX-induced both PIPN and HSR effects in anticancer chemotherapy.

Analysis of nearly 3000 archaeal genomes from terrestrial geothermal springs sheds light on interconnected biogeochemical processes.

Terrestrial geothermal springs are physicochemically diverse and host abundant populations of Archaea. However, the diversity, functionality, and geological influences of these Archaea are not well understood. Here we explore the genomic diversity of Archaea in 152 metagenomes from 48 geothermal springs in Tengchong, China, collected from 2016 to 2021. Our dataset is comprised of 2949 archaeal metagenome-assembled genomes spanning 12 phyla and 392 newly identified species, which increases the known species diversity of Archaea by ~48.6%. The structures and potential functions of the archaeal communities are strongly influenced by temperature and pH, with high-temperature acidic and alkaline springs favoring archaeal abundance over Bacteria. Genome-resolved metagenomics and metatranscriptomics provide insights into the potential ecological niches of these Archaea and their potential roles in carbon, sulfur, nitrogen, and hydrogen metabolism. Furthermore, our findings illustrate the interplay of competition and cooperation among Archaea in biogeochemical cycles, possibly arising from overlapping functional niches and metabolic handoffs. Taken together, our study expands the genomic diversity of Archaea inhabiting geothermal springs and provides a foundation for more incisive study of biogeochemical processes mediated by Archaea in geothermal ecosystems.

Ferviditalea candida gen. nov., sp. nov., a novel member of the family Paenibacillaceae isolated from a geothermal area.

OBJECTIVE: The family Paenibacillaceae is linked to the order Caryophanales. Paenibacillaceae members residing in compost or soil play crucial roles in nutrient recycling and breaking down complex organic materials. However, our understanding of Paenibacillaceae remains limited. METHODS: Strain SYSU GA230002T was conclusively identified using a polyphasic taxonomic approach frequently utilized in bacterial systematics. Standard microbiological techniques were employed to characterize the morphology and biochemistry of strain SYSU GA230002T. RESULTS: An anaerobic and Gram-stain-negative bacterium, designated SYSU GA230002T, was isolated from geothermally heated soil of Tengchong, Yunnan Province, south-west China. Phylogenetic analyses based on 16S rRNA gene sequences and genomes showed that strain SYSU GA230002T belongs to the family Paenibacillaceae. 16S rRNA gene sequence similarity (<94.0%), ANI (<71.95%) and AAI values (<58.67%) between strain SYSU GA230002T with other members of the family were lower than the threshold values recommended for distinguishing novel species. Growth was observed at 30-45ºC (optimum, 37ºC), pH 7.0-8.0 (optimum, pH 7.5) and in 0-3.0% (w/v) NaCl concentrations (optimum, 0%). The major fatty acids detected were anteiso-C15:0, iso-C16:0 and iso-C17:0. The polar lipids included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unidentified phospholipid, one unidentified aminolipid and two unidentified glycolipids. The respiratory quinone was MK-7. The DNA G+C content of strain SYSU GA230002T was 49.87%. CONCLUSION: Based on the results of morphological, physiological properties, and chemotaxonomic characteristics, this strain is proposed to represent a new species of a new genus Ferviditalea candida gen. nov., sp. nov. The type strain of the type species is SYSU GA230002T (=KCTC 25726T=GDMCC 1.4160T).

A 2-order additive fuzzy measure identification method based on hesitant fuzzy linguistic interaction degree and its application in credit assessment.

To reflect both fuzziness and hesitation in the evaluation of interactivity between attributes in the identification process of 2-order additive fuzzy measure, this work uses the hesitant fuzzy linguistic term set (HFLTS) to describe and depict the interactivity between attributes. Firstly, the interactivity between attributes is defined by the supermodular game theory. According to this definition, a linguistic term set is established to characterize the interactivity between attributes. Under the linguistic term set, the experts employ linguistic expressions generated by context-free grammar to qualitatively describe the interactivity between attributes. Secondly, through the conversion function, the linguistic expressions are transformed into the hesitant fuzzy linguistic term sets (HFLTSs). The individual evaluation results of all experts were further aggregated with the defined hesitant fuzzy linguistic weighted power average operator (HFLWPA). Thirdly, based on the standard Euclidean distance formula of the hesitant fuzzy linguistic elements (HFLEs), the hesitant fuzzy linguistic interaction degree (HFLID) between attributes is defined and calculated by constructing a piecewise function. As a result, a 2-order additive fuzzy measure identification method based on HFLID is proposed. Based on the proposed method, using the Choquet fuzzy integral as nonlinear integration operator, a multi-attribute decision making (MADM) process is then presented. Taking the credit assessment of the big data listed companies in China as an application example, the analysis results of application example prove the feasibility and effectiveness of the proposed method. This work successfully reflects both the fuzziness and hesitation in evaluating the interactivity between attributes in the identification process of 2-order additive fuzzy measure, enriches the theoretical framework of 2-order additive fuzzy measure, and expands the applicability and methodology of 2-order additive fuzzy measure in multi-attribute decision making.

Chelativorans salis sp. nov., a slightly halophilic bacterium isolated from an enrichment system with saline lake sediment.

A Gram-stain-negative, non-motile, and slightly halophilic alphaproteobacterium, designated strain EGI FJ00035T, was isolated from enrichment sediment samples of a saline lake in Xinjiang Uygur Autonomous Region, PR China. The taxonomic position of the isolate was determined using the polyphasic taxonomic and phylogenomic analyses. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain EGI FJ00035T formed a distinct clade with 'Chelativorans alearense' UJN715 and 'Chelativorans xinjiangense' lm93 with sequence similarities of 98.44 and 98.22 %, respectively, while sharing less than 96.7 % with other valid type strains. The novel isolate could be distinguished from other species of the genus Chelativorans by its distinct phenotypic, physiological, and genotypic characteristics. Optimal growth of strain EGI FJ00035T occurred on marine agar 2216 at pH 7.0 and 30 °C. The major respiratory quinone was Q-10, while the major fatty acids (>5 %) were C19 : 0 cyclo ω8c, summed feature 8 (C17 : 1 ω6c and/or C17 : 1 ω7c), C16 : 0, C18 : 0, and iso-C17 : 0. The detected polar lipids included diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, unidentified aminophospholipids, unidentified glycolipids, and an unidentified lipid. Based on its genome sequence, the G+C content of strain EGI FJ00035T was 63.2 mol%. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values of strain EGI FJ00035T against related members of the genus Chelativorans were below the thresholds for delineation of a novel species. According our polyphasic taxonomic data, strain EGI FJ00035T represents a new species of the genus Chelativorans, for which the name Chelativorans salis sp. nov. is proposed. The type strain of the proposed novel isolate is EGI FJ00035T (=KCTC 92251T=CGMCC 1.19480T).

Rapid and Complete Digestion of Refractory Geological Samples Using Ultrafine Powder for Accurate Analyses of Trace Elements.

Complete sample digestion is a prerequisite for acquiring high-quality analytical results for geological samples. Closed-vessel acid digestion (bomb) has typically been used for the total digestion of refractory geological samples. However, the long digestion time (4-5 days) and insoluble fluoride complexes still pose challenges for digesting refractory geological samples using this approach. In this study, an efficient and simplified digestion technique combining ultrafine powders from planetary ball milling with bomb digestion was developed for trace element analysis of refractory geological samples: peridotite and granitoid. The method shows two significant improvements compared with previous approaches. (1) By performing dry planetary ultrafine milling, the initial 200 mesh peridotite (<74 µm) could be reduced to 800 mesh (<20 µm) in 6 min at a ball-to-powder mass ratio of approximately 15 using 3 mm tungsten carbide milling balls. (2) Complete peridotite and granitoid dissolution were achieved in approximately 2 h, 60 times faster than what is achievable using previous methods (2 h vs 120 h). Moreover, ultrafine powders effectively suppressed insoluble fluoride formation during bomb digestion. A suite of peridotite and granitoid reference materials were measured to evaluate the stability of this method. This efficient, simple, and reliable sample digestion method could benefit geological, food, environmental, and other fields requiring solid sample decomposition via wet acid, fusion, combustion, or dry ashing.

Chelatococcus albus sp. nov., a bacterium isolated from hot spring microbial mat.

A Gram-stain-negative, non-endospore-forming, motile, short rod-shaped strain, designated SYSU G07232T, was isolated from a hot spring microbial mat, sampled from Rehai National Park, Tengchong, Yunnan Province, south-western China. Strain SYSU G07232T grew at 25-50 °C (optimum, 37 °C), at pH 5.5-9.0 (optimum, pH 6.0) and tolerated NaCl concentrations up to 1.0 % (w/v). Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain SYSU G07232T showed closest genetic affinity with Chelatococcus daeguensis K106T. The genomic features and taxonomic status of this strain were determined through whole-genome sequencing and a polyphasic approach. The predominant quinone of this strain was Q-10. Major cellular fatty acids comprised C19 : 0 cyclo ω8c and summed feature 8. The whole-genome length of strain SYSU G07232T was 4.02 Mbp, and the DNA G+C content was 69.26 mol%. The average nucleotide identity (ANIm ≤84.85 % and ANIb ≤76.08  %) and digital DNA-DNA hybridization (≤ 21.9 %) values between strain SYSU G07232T and the reference species were lower than the threshold values recommended for distinguishing novel prokaryotic species. Thus, based on the provided phenotypic, phylogenetic, and genetic data, it is proposed that strain SYSU G07232T (=KCTC 8141T=GDMCC 1.4178T) be designated as representing a novel species within the genus Chelatococcus, named Chelatococcus albus sp. nov.

Sciscionella sediminilitoris sp. nov., a Marine Actinomycete Isolated from Cape Rochado, Malaysia, and the Emendations to the Description of the Genus Sciscionella.

In this study, we employed a polyphasic approach to determine the taxonomic position of a newly isolated actinomycete, designated SE31T, obtained from a sediment sample collected at Cape Rochado, Malaysia. Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain SE31T belonged to the family Pseudonocardiaceae and exhibited the highest sequence similarity (98.9%) to Sciscionella marina. Further genomic analysis demonstrated a 93.4% average nucleotide identity and 54.4% digital DNA-DNA hybridization relatedness between strain SE31T and S. marina. The chemotaxonomic characteristics of strain SE31T were typical of the genus Sciscionella, including cell-wall chemotype IV (with meso-diaminopimelic acid as the diagnostic diamino acid, and arabinose and galactose as whole-cell sugars). The identified polar lipids of strain SE31T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, and hydroxyphosphatidymethylethanolamine. The primary menaquinone observed was MK-9(H4), and the major cellular fatty acid was iso-C16:0. The genomic DNA size of strain SE31T was determined to be 7.4 Mbp with a G+C content of 68.7%. Based on these comprehensive findings, strain SE31T represents a novel species within the genus Sciscionella, in which the name Sciscionella sediminilitoris sp. nov. is proposed. The type strain of Sciscionella sediminilitoris is SE31T (= DSM 46824T = TBRC 5134T).

Spatiotemporal dual-periodic soliton pulsation in a multimode fiber laser.

Spatiotemporal mode-locked (STML) fiber lasers have become a new platform for investigating nonlinear phenomena. In this work, spatiotemporal dual-periodic soliton pulsation (SDSP) is firstly observed in an STML fiber laser. It is found that in the SDSP, the long-period pulsations (LPPs) of different transverse modes are synchronous, while the short-period pulsations (SPPs) exhibit asynchronous modulations. The numerical simulation confirms the experimental results and further reveals that the proportion of transverse mode components can manipulate the periods of the LPP and SPP but does not affect the synchronous and asynchronous pulsations of different transverse modes. The obtained results bring the study of spatiotemporal dissipative soliton pulsation into the multi-period modulation stage, which helps to understand the complex spatiotemporal dynamics in STML fiber lasers and discover new dynamics in high-dimensional nonlinear systems.

Stomatohabitans albus gen. nov., sp. nov., an oral living facultative anaerobic actinobacteria isolated form Steller sea lion, and proposal of Stomatohabitantaceae fam. nov. and Stomatohabitantales ord. nov.

Two novel actinobacteria, designated as SYSU M7M538T and SYSU M7M531, were isolated from oral of Eumetopias jubatus in Zhuhai Chimelong Ocean Kingdom, China. The cells of these microorganisms stained Gram-positive and were rod shaped. These strains were facultative anaerobic, and catalase-positive. Optimal growth occurred at 37 °C and pH 7.0 over 7 days of cultivation. Both strains possessed diphosphatidylglycerol, phosphatidylglycerol and phosphocholine as the major polar lipids. The main menaquinone was MK-9(H4). The major fatty acids were C16:0, C17:1w8c, C17:0, C18:1w9c and C18:0. Analyses of genome sequences revealed that the genome size of SYSU M7M538T was 2.1 Mbp with G + C content of 52.5 %, while the genome size of SYSU M7M531 was 2.3 Mbp with G + C content of 52.7 %. The ANI and 16S rRNA gene analysis results showed that the pairwise similarities between the two strains and other recognized Nitriliruptoria species were less than 64.9 % and 89.0 %, respectively. Phylogenetic analysis of the 16S rRNA gene sequences indicated that strains SYSU M7M538T and SYSU M7M531 formed a well-separated phylogenetic branch distinct from other orders of Nitriliruptoria. Based on the data presented here, these two strains are considered to represent a novel species of a novel genus, for which the name Stomatohabitans albus gen. nov., sp. nov., with the type strain SYSU M7M538T (=KCTC 59113T = GDMCC 1.4286T), are proposed. We also propose that these organisms represent a novel family named Stomatohabitantaceae fam. nov. of a novel order Stomatohabitantales ord. nov.

Co-occurrence, toxicity, and biotransformation pathways of metformin and its intermediate product guanylurea: Current state and future prospects for enhanced biodegradation strategy.

Accumulation of metformin and its biotransformation product "guanylurea" are posing an increasing concern due to their low biodegradability under natural attenuated conditions. Therefore, in this study, we reviewed the unavoidable function of metformin in human body and the route of its release in different water ecosystems. In addition, metformin and its biotransformation product guanylurea in aquatic environments caused certain toxic effects on aquatic organisms which include neurotoxicity, endocrine disruption, production of ROS, and acetylcholinesterase disturbance in aquatic organisms. Moreover, microorganisms are the first to expose and deal with the release of these contaminants, therefore, the mechanisms of biodegradation pathways of metformin and guanylurea under aerobic and anaerobic environments were studied. It has been reported that certain microbes, such as Aminobacter sp. and Pseudomonas putida can carry potential enzymatic pathways to degrade the dead-end product "guanylurea", and hence guanylurea is no longer the dead-end product of metformin. However, these microbes can easily be affected by certain geochemical cycles, therefore, we proposed certain strategies that can be helpful in the enhanced biodegradation of metformin and its biotransformation product guanylurea. A better understanding of the biodegradation potential is imperative to improve the use of these approaches for the sustainable and cost-effective remediation of the emerging contaminants of concern, metformin and guanylurea in the near future.

A review on endophytic fungi: a potent reservoir of bioactive metabolites with special emphasis on blight disease management.

Phytopathogenic microorganisms have caused blight diseases that present significant challenges to global agriculture. These diseases result in substantial crop losses and have a significant economic impact. Due to the limitations of conventional chemical treatments in effectively and sustainably managing these diseases, there is an increasing interest in exploring alternative and environmentally friendly approaches for disease control. Using endophytic fungi as biocontrol agents has become a promising strategy in recent years. Endophytic fungi live inside plant tissues, forming mutually beneficial relationships, and have been discovered to produce a wide range of bioactive metabolites. These metabolites demonstrate significant potential for fighting blight diseases and provide a plentiful source of new biopesticides. In this review, we delve into the potential of endophytic fungi as a means of biocontrol against blight diseases. We specifically highlight their significance as a source of biologically active compounds. The review explores different mechanisms used by endophytic fungi to suppress phytopathogens. These mechanisms include competing for nutrients, producing antifungal compounds, and triggering plant defense responses. Furthermore, this review discusses the challenges of using endophytic fungi as biocontrol agents in commercial applications. It emphasizes the importance of conducting thorough research to enhance their effectiveness and stability in real-world environments. Therefore, bioactive metabolites from endophytic fungi have considerable potential for sustainable and eco-friendly blight disease control. Additional research on endophytes and their metabolites will promote biotechnology solutions.

Temperature, pH, and oxygen availability contributed to the functional differentiation of ancient Nitrososphaeria.

Ammonia-oxidizing Nitrososphaeria are among the most abundant archaea on Earth and have profound impacts on the biogeochemical cycles of carbon and nitrogen. In contrast to these well-studied ammonia-oxidizing archaea (AOA), deep-branching non-AOA within this class remain poorly characterized because of a low number of genome representatives. Here, we reconstructed 128 Nitrososphaeria metagenome-assembled genomes from acid mine drainage and hot spring sediment metagenomes. Comparative genomics revealed that extant non-AOA are functionally diverse, with capacity for carbon fixation, carbon monoxide oxidation, methanogenesis, and respiratory pathways including oxygen, nitrate, sulfur, or sulfate, as potential terminal electron acceptors. Despite their diverse anaerobic pathways, evolutionary history inference suggested that the common ancestor of Nitrososphaeria was likely an aerobic thermophile. We further surmise that the functional differentiation of Nitrososphaeria was primarily shaped by oxygen, pH, and temperature, with the acquisition of pathways for carbon, nitrogen, and sulfur metabolism. Our study provides a more holistic and less biased understanding of the diversity, ecology, and deep evolution of the globally abundant Nitrososphaeria.

Synthesis and characterization of marine seagrass (Cymodocea serrulata) mediated titanium dioxide nanoparticles for antibacterial, antibiofilm and antioxidant properties.

Cymodocea serrulata mediated titanium dioxide nanoparticles (TiO2 NPs) were successfully synthesized. The XRD pattern and FTIR spectra demonstrated the crystalline structure of TiO2 NPs and the presence of phenols, flavonoids and alkaloids in the extract. Further SEM revealed that TiO2 NPs has uniform structure and spherical in shape with their size ranged from 58 to 117 nm. Antibacterial activity of TiO2 NPs against methicillin-resistant Staphylococcus aureus (MRSA) and Vibrio cholerae (V. cholerae), provided the zone of inhibition of 33.9 ± 1.7 and 36.3 ± 1.9 mm, respectively at 100 µg/mL concentration. MIC of TiO2 NPs against MRSA and V. cholerae showed 84% and 87% inhibition at 180 µg/mL and 160 µg/mL respectively. Subsequently, the sub-MIC of V. cholerae demonstrated minimal or no impact on bacterial growth at concentration of 42.5 µg/mL concentration. In addition, TiO2 NPs exhibited their ability to inhibit the biofilm forming V. cholerae which caused distinct morphological and intercellular damages analysed using CLSM and TEM. The antioxidant properties of TiO2 NPs were demonstrated through TAA and DPPH assays and exposed its scavenging activity with IC50 value of 36.42 and 68.85 µg/mL which denotes its valuable antioxidant properties with potential health benefits. Importantly, the brine shrimp based lethality experiment yielded a low cytotoxic effect with 13% mortality at 100 µg/mL. In conclusion, the multifaceted attributes of C. serrulata mediated TiO2 NPs encompassed the antibacterial, antioxidant and anti-biofilm inhibition effects with low cytotoxicity in nature were highlighted in this study and proved the bioderived TiO2 NPs could be used as a promising agent for biomedical applications.