Draconibacterium aestuarii sp.nov., a Glycolipid-Producing Bacterium Isolated from Tidal Flat Sediment and Emended Description of the Genus Draconibacterium.

A facultatively anaerobic, Gram-negative, curved rod-shaped bacterium (4.0-17.0 µm long, 0.6-0.9 µm wide), designated Z1-6T, was obtained from tidal flat sediment collected from YueAo village in Zhoushan, Zhejiang, People's Republic of China. Strain Z1-6T occurred at 15-45 °C (optimum 28-32 °C), pH 6.0-9.0 (optimum 7.0-7.5), and in the presence of 1-5% (w/v) NaCl (optimum 1-2%). The strain contained iso-C15:0 and antesio-C15:0 as the major fatty acids. An unsaturated menaquinone with seven isoprene units (MK-7) was the predominant respiratory quinone. The polar lipids included phosphatidylethanolamine (PE), one aminophospholipid (APL), two phospholipids (PL1 and PL2), three glycolipids (GL1, GL2, and GL3), and two unidentified lipids (L1 and L2). The genomic DNA G+C content of strain Z1-6T was 39.2%, and the genome size was 6.4 Mb. The strain showed the highest average nucleotide identity (ANI) value of 73.5-74.6%, digital DNA-DNA hybridization (dDDH) value of 19.3-20%, average amino acid identity (AAI) value of 72.0-73.1% with the members of genus Draconibacterium. Phylogenetic analysis based on 16S rRNA gene sequences and genome revealed that strain Z1-6T formed a distinct branch in the clade of the genus Draconibacterium. Based on the phenotypic, phylogenetic, chemotaxonomic analyses and genomic data, strain Z1-6T represents a novel species of the genus Draconibacterium, for which the name Draconibacterium aestuarii sp. nov. (The type strain Z1-6T = MCCC 1K07533T = KCTC 92310T) is proposed.

Flagellimonas baculiformis sp. nov. and Flagellimonas crocea sp. nov., isolated from surface seawater of the Pacific Ocean.

Two Gram-negative, non-spore-forming, non-motile, non-flagellated bacteria, designated strains D6T and DH64T, were isolated from surface water of the Pacific Ocean. For strain D6T, growth occurred at 10-40 °C, pH 5.5-9.0 and in the presence of 0-8.0 % NaCl (w/v). For strain DH64T, growth occurred at 10-40 °C, pH 5.5-8.5 and in the presence of 0.5-8.0 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains D6T and DH64T both belonged to the genera Flagellimonas, with the highest sequence identities to Flagellimonas taeanensis JCM 17757T (98.2 %) and Flagellimonas marinaquae JCM 11811T (98.6 %), respectively. The 16S rRNA gene sequence identity between strains D6T and DH64T was 95.9 %. The average amino acid identity and digital DNA-DNA hybridization values between the two strains and the nearest phylogenetic neighbours were 66.7-93.3 % and 16.1-38.5 %, respectively. The major respiratory quinone of both strains was menaquinone-6. The major polar lipid was phosphatidylethanolamine. The major fatty acids were identified similarly as iso-C15 : 1 G, iso-C15 : 0 and iso-C17 : 0 3-OH. The genomic G+C contents of strains D6T and DH64T were determined to be 45.5 and 42.6 mol%, respectively. The combined genotypic and phenotypic data show that the strains represent two novel species within genera Flagellimonas, for which the names Flagellimonas baculiformis sp. nov. and Flagellimonas crocea sp. nov. are proposed, with type strains D6T (=MCCC M28982T=KCTC 92604T) and DH64T (=MCCC M28986T=KCTC 92975T).

Qipengyuania benthica sp. nov. and Qipengyuania profundimaris sp. nov., two novel Erythrobacteraceae members isolated from deep-sea environments.

Two Gram-stain-negative, rod-shaped and non-motile strains, designated as DY56-A-20T and G39T, were isolated from deep-sea sediment of the Pacific Ocean and deep-sea seawater of the Indian Ocean, respectively. Strain DY56-A-20T was found to grow at 15-37 °C (optimum, 28 °C), at pH 6.0-10.0 (optimum, pH 6.5-7.0) and in 0.5-6.0 % (w/v) NaCl (optimum, 1.0-2.0 %), while strain G39T was found to grow at 10-42 °C (optimum, 35-40 °C), at pH 5.5-10.0 (optimum, pH 6.5-7.0) and in 0-12.0 % (w/v) NaCl (optimum, 1.0-2.0 %). The 16S rRNA gene sequence identity analysis indicated that strain DY56-A-20T had the highest sequence identity with Qipengyuania marisflavi KEM-5T (97.6 %), while strain G39T displayed the highest sequence identity with Qipengyuania citrea H150T (98.8 %). The phylogenomic reconstruction indicated that both strains formed independent clades within the genus Qipengyuania. The digital DNA-DNA hybridization and average nucleotide identity values between strains DY56-A-20T/G39T and Qipengyuania/Erythrobacter type strains were 17.8-23.8 % and 70.7-81.1 %, respectively, which are below species delineation thresholds. The genome DNA G+C contents were 65.0 and 63.5 mol% for strains DY56-A-20T and G39T, respectively. The predominant cellular fatty acids (>10 %) of strain DY56-A-20T were C17 : 1 ω6c, summed feature 8 and summed feature 3, and the major cellular fatty acids of strain G39T were C17 : 1 ω6c and summed feature 8. The major polar lipids in both strains were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, sphingoglycolipid and an unidentified polar lipid. The only respiratory quinone present in both strains was ubiquinone-10. Based on those genotypic and phenotypic results, the two strains represent two novel species belonging to the genus Qipengyuania, for which the names Qipengyuania benthica sp. nov. and Qipengyuania profundimaris sp. nov. are proposed. The type strain of Q. benthica is DY56-A-20T (=MCCC M27941T=KCTC 92309T), and the type strain of Q. profundimaris is G39T (=MCCC M30353T=KCTC 8208T).

Metagenome-based analysis of carbon-fixing microorganisms and their carbon-fixing pathways in deep-sea sediments of the southwestern Indian Ocean.

Carbon fixation by chemoautotrophic microorganisms in the dark ocean makes a large contribution to oceanic primary production and the global carbon cycle. In contrast to the Calvin cycle-dominated carbon-fixing pathway in the marine euphotic zone, carbon-fixing pathways and their hosts in deep-sea areas are diverse. In this study, four deep-sea sediment samples close to hydrothermal vents in the southwestern Indian Ocean were collected and processed using metagenomic analysis to investigate carbon fixation potential. Functional annotations revealed that all six carbon-fixing pathways had genes to varied degrees present in the samples. The reductive tricarboxylic acid cycle and Calvin cycle genes occurred in all samples, in contrast to the Wood-Ljungdahl pathway, which previous studies found mainly in the hydrothermal area. The annotations also elucidated the chemoautotrophic microbial members associated with the six carbon-fixing pathways, and the majority of them containing key carbon fixation genes belonged to the phyla Pseudomonadota and Desulfobacterota. The binned metagenome-assembled genomes revealed that key genes for the Calvin cycle and the 3-hydroxypropionate/4-hydroxybutyrate cycle were also found in the order Rhodothermales and the family Hyphomicrobiaceae. By identifying the carbon metabolic pathways and microbial populations in the hydrothermal fields of the southwest Indian Ocean, our study sheds light on complex biogeochemical processes in deep-sea environments and lays the foundation for further in-depth investigations of carbon fixation processes in deep-sea ecosystems.

Membranihabitans maritimus sp. nov., a marine bacterium isolated from deep seawater.

A Gram-stain-negative, non-motile, rod-shaped bacterial strain, designated C281T, was isolated from seawater sampled at the Marshallese seamount chain. Results of 16S rRNA gene analysis revealed that strain C281T was most closely related to Membranihabitans marinus CZ-AZ5T with 92.7 % sequence similarity. Phylogenetic analysis indicated that the new isolate represented a novel species by forming a distinctive lineage within the family Saprospiraceae. The DNA G+C content of strain C281T was 38.4 mol%. The genome sizes of strain C281T and the reference strain M. marinus CZ-AZ5T were 5 962 917 and 5 395 999 bp, respectively. The average nucleotide identity and in silico DNA-DNA hybridization values between strains C281T and M. marinus CZ-AZ5T were found to be low (69.3 and 17.6 %, respectively). Different functional genes were found in the genome of strain C281T, such as CZC CBA, polysaccharide utilization loci and linear azol(in)e-containing peptide cluster coding genes. The NaCl range for growth was 0.5-15.0 %. Positive results were obtained for hydrolysis of Tween 60 and urease. MK-7 was the sole respiratory quinone. The major fatty acids were C16 : 1 ω6c and/or C16 : 1 ω7c, iso-C15 : 0 and iso-C15 : 1 F. The major polar lipids of strain C281T were phosphatidylethanolamine, phosphatidylglycerol, two unidentified lipids and five unidentified glycolipids. On the basis of its taxonomic characteristics, the isolate represents a novel species of the genus Membranihabitans, for which the name Membranihabitans maritimus sp. nov. (type strain C281T=KCTC 92171T=MCCC M27001T) is proposed.

The double-edged sword effects of active social media use on loneliness: The roles of interpersonal satisfaction and fear of missing out.

Introduction: Social media' impact on loneliness has attracted widespread scholarly attention. One hypothesis is that active social media use (ASMU) is associated with a decrease in loneliness. However, several empirical studies did not find a significant correlation between ASMU and loneliness, and ASMU may even increase loneliness. This study explored the mechanism of the double-edged sword effects of ASMU on loneliness. Methods: Data were collected through convenience sampling from three universities in China. A total of 454 Chinese college social media users (Mean age 19.75 ± 1.33; 59.92% female) completed an online questionnaire. Results: ASMU was positively related to interpersonal relationship satisfaction, which was negatively related to general trait-fear of missing out (FoMO) and loneliness. Further structural equation modeling (SEM) analysis showed that ASMU could negatively predict loneliness through the mediation pathways of interpersonal satisfaction and "Interpersonal satisfaction → Trait-FoMO." At the same time, ASMU was also positively associated with online-specific state-FoMO, which was positively associated with trait-FoMO and loneliness. Further SEM analysis found no mediation effect of state-FoMO between ASMU and loneliness, but state-FoMO and traitFoMO sequentially mediate the relationship between ASMU and loneliness. Discussion: This study indicates that ASMU may increase and decrease loneliness. Interpersonal satisfaction and FoMO explained the double-edged mechanism of ASMU on loneliness. These findings contribute to dialectically understanding the effectiveness of active social media use and provide theoretical guidance for promoting the beneficial aspects of social media while weakening its harmful consequences.

Modeling the viscoelastic relaxation dynamics of soft particles via molecular dynamics simulation-informed multi-dimensional transition-state theory.

Viscoelastic soft colloidal particles have been widely explored in mechanical, chemical, pharmaceutical and other engineering applications due to their unique combination of viscosity and elasticity. The characteristic viscoelastic relaxation time shows an Arrhenius-type (or super-Arrhenius due to temperature-dependent transition attempts) thermally-activated behavior, but a holistic explanation from the relevant transition-state theory remains elusive. In this paper, the viscoelastic relaxation times of Lennard-Jones soft colloidal particle systems, including a single particle type system and a binary particle mixture based on the Kob-Andersen model, are determined using molecular dynamics (MD) simulations as the benchmark. First, the particle systems show a non-Maxwellian behavior after comparing the MD-predicted viscoelastic relaxation time and dynamic moduli (storage and loss modulus) to the classic Maxwell viscoelastic model and the recent particle local connectivity theory. Surprisingly, neither the Maxwell relaxation time τMaxwell (obtained from the static shear viscosity η and the high-frequency shear modulus G∞) nor the particle local connectivity lifetime τLC can capture the super-Arrhenius temperature-dependent behavior in the MD-predicted relaxation time τMD. Then, the particle dissociation and association transition kinetics, fractal dimensions of the particle systems, and neighbor particle structure (obtained from the radial distribution functions) are shown to collectively determine the viscoelastic relaxation time. These factors are embedded into a new multi-dimensional transition kinetics model to directly estimate the viscoelastic relaxation time τModel, which is found to agree with the MD-predicted τMD remarkably well. This work highlights the microscopic origin of viscoelastic relaxation dynamics of soft colloidal particles, and theoretically connects rheological dynamics and transition kinetics in soft matters.

Linking microbiomes with per- and poly-fluoroalkyl substances (PFASs) in soil ecosystems: Microbial community assembly, stability, and trophic phylosymbiosis.

Microbiomes are vital in promoting nutrient cycling and plant growth in soil ecosystems. However, microbiomes face adverse effects from multiple persistent pollutants, including per- and poly-fluoroalkyl substances (PFASs). PFASs threaten the fertility and health of soil ecosystems, yet the response of microbial community stability and trophic transfer efficiencies to PFASs is still poorly understood. This study explored the spatial patterns of PFASs in topsoil environments from the West Taihu Lake Basin of China and links their presence to soil microbial community stability at compositional and functional levels. Our results revealed that PFBA (13.87%), PFTrDA (11.63%), PFDoA (11.02%), PFOA (10.99%), and PFOS (10.39%) contributed the most to the spatial occurrence of PFASs. Soil properties, including salinity (14.47%), uniformity (9.68%), dissolved inorganic carbon (8.62%), and clay content (8.18%), affected PFASs distribution the most. In soil microbiomes, eukaryotic taxa had wider niche breadths and stronger community stability than prokaryotes when exposed to PFASs (p < 0.05). The presence of PFBA and PFHpA inhibited the functional stability of archaeal and bacterial communities (p < 0.05). PFBA and PFPeA reduced the structural stability of heterotrophic bacteria and Myxobacteria, respectively (p < 0.05). Based on null modeling, PFPeA significantly regulated the assembly processes of most microbial sub-communities (p < 0.01). The trophic transferring efficiencies of autotrophic bacteria to metazoan organisms were directly stimulated by PFASs (p < 0.05), and the potential trophic transferring efficiencies of methanogenic archaea to protozoa were inhibited by PFASs (p < 0.05). This study highlighted the potential contributions of PFASs to soil microbial community stability and food webs during ecological soil management.

Aestuariibaculum sediminum sp. nov., a marine bacterium isolated from a tidal flat in Zhoushan.

A Gram-staining-negative, non-motile, strictly aerobic bacterium, designated as strain TT11T, was isolated from a sediment sample of a tidal flat connected in Zhoushan, China. Cells of strain TT11T are spherical, halotolerant, catalase- and oxidase-positive, and produce carotenoid-like pigments. Colonies were 0.5-1.0 mm diameter, smooth, round, convex and orange-yellow after growth on marine agar at 30 °C for 24 h. Growth of the strain TT11T was observed at 10-40 °C (optimum, 35 °C), at pH 6.0-9.5 (optimum, pH 6.5), and in the presence of 0-8.0% (w/v) NaCl (optimum, 0.5-1.0%). The results of 16S rRNA gene sequence analysis revealed that strain TT11T represents a member of the genus Aestuariibaculum and was closely related to Aestuariibaculum suncheonense SC17T (97.2%) and Aestuariibaculum marinum IP7T (96.8%). The G + C content of the genome was 34.6%. The only respiratory quinone was MK-6. The major fatty acids (> 10%) were iso-C15:0, iso-C15:1 G and iso-C17:0 3-OH. The major polar lipids contained phosphatidylethanolamine, phosphoglycolipid, four unidentified aminolipids, four unidentified lipids and two unidentified glycolipids. On the basis of these genomic, chemotaxonomic and phenotypic characteristics, we propose a novel species Aestuariibaculum sediminum sp. nov. with the type strain TT11T (= KCTC 82195T = MCCC 1K04734T).

Long-chain acyl-CoA synthetase 2 is involved in seed oil production in Brassica napus.

BACKGROUND: Triacylglycerols (TAGs) are the main composition of plant seed oil. Long-chain acyl-coenzyme A synthetases (LACSs) catalyze the synthesis of long-chain acyl-coenzyme A, which is one of the primary substrates for TAG synthesis. In Arabidopsis, the LACS gene family contains nine members, among which LACS1 and LACS9 have overlapping functions in TAG biosynthesis. However, functional characterization of LACS proteins in rapeseed have been rarely reported. RESULTS: An orthologue of the Arabidopsis LACS2 gene (BnLACS2) that is highly expressed in developing seeds was identified in rapeseed (Brassica napus). The BnLACS2-GFP fusion protein was mainly localized to the endoplasmic reticulum, where TAG biosynthesis occurs. Interestingly, overexpression of the BnLACS2 gene resulted in significantly higher oil contents in transgenic rapeseed plants compared to wild type, while BnLACS2-RNAi transgenic rapeseed plants had decreased oil contents. Furthermore, quantitative real-time PCR expression data revealed that the expression of several genes involved in glycolysis, as well as fatty acid (FA) and lipid biosynthesis, was also affected in transgenic plants. CONCLUSIONS: A long chain acyl-CoA synthetase, BnLACS2, located in the endoplasmic reticulum was identified in B. napus. Overexpression of BnLACS2 in yeast and rapeseed could increase oil content, while BnLACS2-RNAi transgenic rapeseed plants exhibited decreased oil content. Furthermore, BnLACS2 transcription increased the expression of genes involved in glycolysis, and FA and lipid synthesis in developing seeds. These results suggested that BnLACS2 is an important factor for seed oil production in B. napus.

The Complete Genome of Emcibacter congregatus ZYLT, a Marine Bacterium Encoding a CRISPR-Cas 9 Immune System.

Emcibacter congregatus ZYLT was isolated from a sediment sample cultured in situ in a coast located in the East China Sea. The genome of E. congregatus ZYLT was sequenced and assembled into one single circular chromosome with the size of 4,189,011 bp and G+C content of 52.6%. Genomic annotation showed that E. congregatus ZYLT had an intact Type II-C CRISPR-Cas system consists of three cas genes (cas 9, cas 1, and cas 2), 34 direct repeat sequences with the length of 36 bp, and 33 spacers. The predicted Cas 9 protein was smaller than most of existing genome editing tools. This structure might have potential in developing new gene editing system and uncovering the regulatory mechanisms of CRISPR-Cas system. Besides, the comparison between E. congregatus ZYLT and its relative species living in neritic environments unraveled some common traits of the defective strategies of these bacteria to face inshore challenges including the motility, multidrug resistance, and universal efflux pumps.

Marortus luteolus gen. nov., sp. nov., isolated from surface seawater of the East Sea in China.

A Gram-stain-negative, motile, aerobic, rod-shaped bacterium with flagella, designated ZX-21T, was isolated from surface seawater of the East Sea in Zhoushan, China. Growth of strain ZX-21T was observed at 10--35 o°C (optimum, 30 °C), at pH 6.0-8.5 (pHoptimum 6.5-7.0) and in the presence of 0.5-8 % (w/v) NaCl (optimum 3-4 %). It was positive for oxidase and catalase activity. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZX-21T constituted an independent lineage within the family Spongiibacteraceae and was most closely related to Zhongshania guokunii (96.83 %). Strain ZX-21T contained ubiquinone-8 (Q-8) as the sole isoprenoid quinone and summed feature 3 (C16 : 1ω77c and/or C16 : 1ω66c), summed feature 8 (C18 : 1ω77c and/or C18 : 1ω66c) and C16 : 0 as the major fatty acids. Phosphatidylglycerol (), phosphatidylethanolamine (), diphosphatidylglycerol () and an unidentified glycolipid were the major cellular polar lipids. The DNA G+C content was 49.1 mol%. Based on itsthe morphological, physiological and chemotaxonomic characteristics, strain ZX-21Tis described as a novel species in a novel genus for whichwith the name Marortus luteolus gen. nov., sp. nov. (type strain ZX-21T = MCCC 1K03431T=KCTC 62160T) is proposed.

Azoarcus pumilus sp. nov., isolated from seawater in Sanya, China.

A novel Gram-stain-negative, motile, rod-shaped (0.4-0.5×1.0-2.0 µm) strain with one polar flagellum, designated SY39T, was isolated from seawater in Sanya, China. Strain SY39T was able to grow at 15-40 °C (optimum, 35-37 °C), pH 6.5-8.5 (pH 8.0) and 0.5-6.0 % (w/v) NaCl (3.5 %). Chemotaxonomic analysis showed that the isoprenoid quinones were Q-8 (88.6 %) and Q-7 (11.4 %). The dominant fatty acids were C16 : 0 and summed feature 3 (C16 : 1ω7c/C16 : 1ω6c). The polar lipids of strain SY39T consisted of diphosphatidyglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unknown phosphoglycolipid, one unknown glycolipid and two unknown aminophosphoglycolipids. The DNA G+C content of the genomic DNA was 66.5 mol%. The phylogenetic analysis of 16S rRNA gene sequences showed that strain SY39T belongs to the genus Azoarcus with similarity ranging from 92.3 to 95.2 %. Based on the phenotypic, chemotaxonomic and phylogenetic features, strain SY39T is concluded to represent a novel species of the genus Azoarcus, for which the name Azoarcus pumilus sp. nov. is proposed. The type strain is SY39T (=KCTC 62157T=MCCC 1K03430T).

Investigation of the AQP Family in Soybean and the Promoter Activity of TIP2;6 in Heat Stress and Hormone Responses.

Aquaporins (AQPs) are one diverse family of membrane channel proteins that play crucial regulatory roles in plant stress physiology. However, the heat stress responsiveness of AQP genes in soybean remains poorly understood. In this study, 75 non-redundant AQP encoding genes were identified in soybean. Multiple sequence alignments showed that all GmAQP proteins possessed the conserved regions, which contained 6 trans-membrane domains (TM1 to TM6). Different GmAQP members consisted of distinct Asn-Pro-Ala (NPA) motifs, aromatic/arginine (ar/R) selectivity filters and Froger's positions (FPs). Phylogenetic analyses distinguished five sub-families within these GmAQPs: 24 GmPIPs, 24 GmTIPs, 17 GmNIPs, 8 GmSIPs, and 2 GmXIPs. Promoter cis-acting elements analyses revealed that distinct number and composition of heat stress and hormone responsive elements existed in different promoter regions of GmAQPs. QRT-PCR assays demonstrated that 12 candidate GmAQPs with relatively extensive expression in various tissues or high expression levels in root or leaf exhibited different expression changes under heat stress and hormone cues (abscisic acid (ABA), l-aminocyclopropane-l-carboxylic acid (ACC), salicylic acid (SA) and methyl jasmonate (MeJA)). Furthermore, the promoter activity of one previously functionally unknown AQP gene-GmTIP2;6 was investigated in transgenic Arabidopsis plants. The beta-glucuronidase (GUS) activity driven by the promoter of GmTIP2;6 was strongly induced in the heat- and ACC-treated transgenic plants and tended to be accumulated in the hypocotyls, vascular bundles, and leaf trichomes. These results will contribute to uncovering the potential functions and molecular mechanisms of soybean GmAQPs in mediating heat stress and hormone signal responses.

Triterpenoids manipulate a broad range of virus-host fusion via wrapping the HR2 domain prevalent in viral envelopes.

A trimer-of-hairpins motif has been identified in triggering virus-cell fusion within a variety of viral envelopes. Chemically manipulating such a motif represents current repertoire of viral fusion inhibitors. Here, we report that triterpenoids, a class of natural products, antagonize this trimer-of-hairpins via its constitutive heptad repeat-2 (HR2), a prevalent α-helical coil in class I viral fusion proteins. Triterpenoids inhibit the entry of Ebola, Marburg, HIV, and influenza A viruses with distinct structure-activity relationships. Specifically, triterpenoid probes capture the viral envelope via photocrosslinking HR2. Profiling the Ebola HR2-triterpenoid interactions using amino acid substitution, surface plasmon resonance, and nuclear magnetic resonance revealed six residues accessible to triterpenoids, leading to wrapping of the hydrophobic helix and blocking of the HR1-HR2 interaction critical in the trimer-of-hairpins formation. This finding was also observed in the envelopes of HIV and influenza A viruses and might potentially extend to a broader variety of viruses, providing a mechanistic insight into triterpenoid-mediated modulation of viral fusion.

Emcibacter congregatus sp. nov., isolated from sediment cultured in situ.

A Gram-negative, aerobic, motile, rod-shaped, pale-yellow bacterial strain, designated as ZYLT, isolated from a cultured in situ sediment sample collected from the East China Sea coast, was studied using a polyphasic taxonomic approach. Strain ZYLT grew at 4-30 °C (optimum, 25 °C), at pH 6.0-8.5 (pH 7.0) and with 0-7.0 % (w/v) NaCl (2.0 %). Results of phylogenetic analysis based on 16S rRNA gene sequences clearly showed that strain ZYLT and Emcibacter nanhaiensis HTCJW17T, which was most closely related to strain ZYLT with 93.6 % sequence similarity, clustered together. The genomic DNA G+C content was 51.5 % (genome sequence). The quinone system was composed only of ubiquinone-10. Strain ZYLT possessed C18 : 1ω7c and/or C18 : 1ω6c (summed feature 8), iso-C15 : 0 2-OH and/or C16 : 1ω7c (summed feature 3), C14 : 0 2-OH and C14 : 0 as the major fatty acids. The content of summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c) in strain ZYLT was far greater than that in E. nanhaiensis. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, three unidentified aminophospholipids, three unidentified phospholipids, one unidentified aminolipid and four unidentified lipids. One unidentified aminophospholipid and two unidentified lipids present in strain ZYLT were not found in E. nanhaiensis in this research. On the basis of phenotypic, phylogenetic and chemotaxonomic data, strain ZYLT (=KCTC 62328T=JCM 32378T=MCCC 1K03526T) represents a novel species of the genus Emcibacter for which the name Emcibacter congregatus sp. nov. is proposed.

Marinicaulis flavus gen. nov., sp. nov., a novel stalked bacterium of the family Parvularculaceae.

A Gram-stain-negative, aerobic, ovoid or short rod-shaped bacterium with prosthecates and flagella, designated SY-3-19T, was isolated from the surface seawater of the South China Sea, and subjected to a polyphasic taxonomic study. The isolate grew at 4-40 °C and pH 5.0-9.0 (optimum 28 °C and pH 6.5-7.5), and with 0.5-16.0 % (w/v) NaCl (optimum 4 %). It was positive for oxidase and catalase activity. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SY-3-19T constituted a separate branch in the family Parvularculaceae, sharing the highest sequence similarities to the genera Aquisalinus (91.9 %), Amphiplicatus (91.1 %) and Parvularcula(91.0-89.4 %). The sole respiratory quinone was ubiquinone-10 and the principal fatty acids (>10 %) were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), 11 methyl C18 : 1ω7c and C16 : 0. The polar lipids of strain SY-3-19T consisted of phosphatidylglycerol, nine unidentified glycolipids and four unidentified lipids. The DNA G+C content was 60.9 mol%. On the basis of morphological, physiological and chemotaxonomic characteristics, together with the results of phylogenetic analysis, strain SY-3-19T is described as a novel species in a novel genus, for which the name Marinicaulis flavus gen. nov., sp. nov. (type strain SY-3-19T=MCCC 1K03432T=KCTC 62156T) is proposed.

Berberine alleviates oxidative stress in rats with osteoporosis through receptor activator of NF-kB/receptor activator of NF-kB ligand/osteoprotegerin (RANK/RANKL/OPG) pathway.

Previous studies suggested that oxidative stress is related to the onset and development of osteoporosis. Moreover, it was demonstrated that berberine has a protective effect against oxidative stress-induced injuries. In this study, we aimed to investigate the effect and mechanism of action of berberine on rats with induced osteoporosis. Sixty 8-week-old female Wistar rats were randomly divided into the following 6 groups: control saline-treated, osteoporosis saline-treated, 3 osteoporosis berberine-treated groups (Ber 5, 10, and 20 mg/kg/body weight, respectively), and osteoporosis alendronate-treated (ALD) group. Osteoporosis was induced by bilateral ovariectomy. All treatments were performed for 8 weeks. The bone mineral density (BMD), serum alkaline phosphatase (ALP), osteocalcin, calcium, phosphorus, superoxide dismutase (SOD), methylenedioxyamphetamine (MDA), and glutathione peroxidase (GSH-Px) level was determined in the rat femur tissue. The gene and protein expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) was analyzed by quantitative reverse transcription PCR and Western blot, respectively. The BMD, SOD and GSH⁃Px levels, and the expression of OPG were significantly lower in osteoporosis compared to control group (all p < 0.05). The serum levels of osteocalcin, ALP, and MDA, and the expression of RANKL were significantly higher in osteoporosis compared to control group (all p < 0.05). Berberine, especially the high doses of berberine, effectively increased SOD, GSH⁃Px, and OPG levels as well as decreased serum osteocalcin, ALP, MDA and RANKL levels in berberine-treated osteoporosis groups (all p < 0.05). To conclude, oxidative stress may promote the development of osteoporosis in rats through the RANK/RANKL/OPG pathway. The antioxidative effect of berberine reduces the development of osteoporosis in rats to some extent.

Aestuarium zhoushanense gen. nov., sp. nov., Isolated from the Tidal Flat.

A gram-stain-negative, aerobic, ovoid or short rod-shaped, and non-motile strain, designed G7T was isolated from a tidal flat sample collected from the coast of East Sea in Zhoushan, China. Strain G7T grew at 4-40 °C and pH 6.0-9.0 (optimum, 28 °C and pH 7.5) and with 0-7% (w/v) NaCl (optimum, 1%). The predominant respiratory quinone was Q-10 and the major fatty acids (>10%) identified were C18:1 ω7c, C16:0 and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c). The polar lipids of strain G7T consisted of phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, and four unidentified lipids. The genomic DNA G+C content was 56.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain G7T formed a distinct lineage belonging to the Roseobacter clade of the family Rhodobacteraceae. On the basis of morphological, physiological, and chemotaxonomic characteristics, together with the results of phylogenetic analysis, strain G7T is described as a novel species in a new genus, for which the name Aestuarium zhoushanense gen. nov., sp. nov. (type strain G7T = MCCC 1K03229T = KCTC 52584T) is proposed.

Hyphococcus flavus gen. nov., sp. nov., a novel alphaproteobacterium isolated from deep seawater.

A Gram-staining-negative, aerobic, non-spore-forming, coccoid to rod shaped bacteria with prosthecate and flagellum, designated as HSF6T, was isolated from deep seawater samples collected from the South China Sea at depth of 2.5 km and subjected to a polyphasic taxonomic investigation. Colonies of strain HSF6T were 1-2 mm in diameter, smooth, circular, convex and yellow. Strain HSF6T was found to grow at 15-37 °C (optimum, 25-35 °C), pH 5.0-9.5 (optimum, pH 7.0-7.5) and with 0-8 % (w/v) NaCl (optimum, 2 %). Chemotaxonomic analysis showed the predominant respiratory quinone of strains HSF6T were ubiquinone-10, and the major fatty acids were C18 : 1ω7c, C16 : 0 and 11-methyl C18 : 1ω7c. The polar lipids were monoglycosyldiglyceride (MGDG), sulfo-quinovosyl diacylglycerol (SQDG), three unknown glycolipids (GL1-3) and five unknown lipids (L1-5). The DNA G+C content of strain HSF6T was determined to be 51.0 mol% with HPLC. The comparison of 16S rRNA gene sequence similarities show that strain HSF6T was related most closely to genus Parvularcula with similarity ranging from 91.0 to 91.8 %. The phylogenetic trees, using the 16S rRNA gene sequence, reconstructed with neighbour-joining, maximum-parsimony and maximum-likelihood methods showed that strain HSF6T constituted a separated branch in the family 'Parvularculaceae'. Differential phenotypic properties, together with the phylogenetic distinctiveness, demonstrated that strain HSF6T is clearly distinct from validly published genera. On the basis of these features, we propose strain HSF6T (=MCCC 1K03223T=KCTC 52486T) represents a novel species of a novel genus with the name Hyphococcus flavus gen. nov., sp. nov.