Pericyte activation accompanied by peritubular capillaries dysfunction and pericyte-to-myofibroblast transition is associated with renal fibrosis in diabetic nephropathy.

Background: Tubulointerstitial renal fibrosis is an essential feature of diabetic nephropathy (DN). Pericytes play a critical role in microvascular diseases and renal fibrogenesis. However, the role of pericytes in DN remains unclear. Herein, we aimed to explore the properties and possible mechanisms of pericytes in renal fibrosis in DN. Methods: We used multiplex immunofluorescence staining to evaluate the location and expression of activated pericytes and to assess capillary dilation and interstitial fibrosis in the kidneys of db/db mice. Pericytes were co-stained for alpha-smooth muscle actin (α-SMA) to determine which ones differentiate into myofibroblasts in db/db mice. Expression of CD34 and platelet-derived growth factor receptor beta (PDGFR-ß) was assessed in kidney tissue from patients with DN by immunohistochemical staining. Results: We found that cell staining for nerve/glial antigen 2 (NG2)+ and PDGFR-ß+ was greater in the kidneys of db/db mice than in those of db/m mice. There was impaired pericyte coverage of blood vessels and capillary dilation in the renal interstitium. These changes were accompanied by increased collagen I staining and an increase in the number of pericytes with profibrotic phenotypes, as identified by increased NG2+/PDGFR-ß+/α-SMA+ and decreased NG2+/PDGFR-ß+/α-SMA- staining. In DN patients, expression of PDGFR-ß was stronger and there was loss of CD34 compared with the findings in control patients with minor glomerular lesions. Conclusion: In this study, we demonstrated that pericyte activation accompanied by peritubular capillary dysfunction and pericytemyofibroblast transition is associated with renal fibrosis in DN.

MicroRNA-299-3p inhibits cell proliferation, motility, invasion and angiogenesis via VEGFA in upper tract urothelial carcinoma.

BACKGROUND: Upper tract urothelial carcinoma (UTUC) is a rare tumor with extraordinarily different features between Eastern and Western countries. Vascular endothelial growth factor-A (VEGFA) was originally identified as a secreted signaling protein and regulator of vascular development and cancer progression. In this study, we aimed to elucidate the molecular mechanisms underlying the regulation of VEGFA by microRNA in UTUC. METHODS: VEGFA expression was evaluated by immunohistochemistry in 140 human UTUC tissue samples. Next, we assessed the regulatory relationship between VEGFA and miR-299-3p by real-time PCR, western blotting, ELISA and dual-luciferase reporter assays using two UTUC cell lines. The role of miR-299-3p/VEGFA in cell proliferation, motility, invasion, and tube formation was analyzed in vitro. RESULTS: High VEGFA expression was significantly associated with tumor stage, grade, distant metastasis and cancer-related death and correlated with poor progression-free and cancer-specific survival. VEGFA knockdown repressed proliferation, migration, invasion and angiogenesis in UTUC cell lines. miR-299-3p significantly reduced VEGFA protein expression and miR-299-3p overexpression inhibited VEGFA mRNA and protein expression by directly targeting its 3'-UTR. Functional studies indicated that VEGFA overexpression reversed the miR-299-3p-mediated suppression of tumor cell proliferation, migration, invasion and angiogenesis. In addition, miR-299-3p/VEGFA suppressed cellular functions in UTUC by modulating the expression of P18 and cyclin E2. CONCLUSIONS: Our findings suggest that miR-299-3p possibly suppresses UTUC cell proliferation, motility, invasion and angiogenesis via VEGFA. VEGFA may act as a prognostic predictor, and both VEGFA and miR-299-3p could be potential therapeutic targets for UTUC.

Shape Dependence of Silver-Nanoparticle-Mediated Synthesis of Gold Nanoclusters with Small Molecules as Capping Ligands.

In this study, differently shaped silver nanoparticles used for the synthesis of gold nanoclusters with small capping ligands were demonstrated. Silver nanoparticles provide a reaction platform that plays dual roles in the formation of Au NCs. One is to reduce gold ions and the other is to attract capping ligands to the surface of nanoparticles. The binding of capping ligands to the AgNP surface creates a restricted space on the surface while gold ions are being reduced by the particles. Four different shapes of AgNPs were prepared and used to examine whether or not this approach is dependent on the morphology of AgNPs. Quasi-spherical AgNPs and silver nanoplates showed excellent results when they were used to synthesize Au NCs. Spherical AgNPs and triangular nanoplates exhibited limited synthesis of Au NCs. TEM images demonstrated that Au NCs were transiently assembled on the surface of silver nanoparticles in the method. The formation of Au NCs was observed on the whole surface of the QS-AgNPs if the synthesis of Au NCs was mediated by QS-AgNPs. In contrast, formation of Au NCs was only observed on the edges and corners of AgNPts if the synthesis of Au NCs was mediated by AgNPts. All of the synthesized Au NCs emitted bright red fluorescence under UV-box irradiation. The synthesized Au NCs displayed similar fluorescent properties, including quantum yields and excitation and emission wavelengths.

MicroRNA-145-5p suppresses cell proliferation, migration, and invasion in upper tract urothelial carcinoma by targeting 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase.

Upper tract urothelial carcinoma (UTUC), including renal, pelvic, and ureteral carcinoma, has a high incidence rate in Taiwan, which is different from that in Western countries. Therefore, it is imperative to elucidate the mechanisms underlying UTUC growth and metastasis. To explore the function of miR-145-5p in UTUC, we transfected the BFTC909 cell line with miR-145-5p mimics and analyzed the differences in protein levels by performing two-dimensional polyacrylamide gel electrophoresis. Real-time polymerase chain reaction and Western blot analysis were used to analyze 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/inositol monophosphate cyclohydrolase (ATIC) messenger RNA and protein levels. A dual-luciferase assay was performed to identify the target of miR-145-5p in ATIC. The effects of miR-145-5p and ATIC expression by cell transfection on cell proliferation, migration, and invasion were also assessed. miR-145-5p downregulated ATIC protein expression. High ATIC expression is associated with tumor stage, metastasis, recurrence, and a poor prognosis in patients with UTUC. Cell function assays revealed that ATIC knockdown inhibited the proliferation, migration, and invasive abilities of UTUC cells. In contrast, miR-145-5p affected the proliferation, migration, and invasive abilities of UTUC cells by directly targeting the 3'-untranslated regions of ATIC. Furthermore, we used RNA sequencing and Ingenuity Pathway Analysis to identify possible downstream genes regulated by ATIC and found that miR-145-5p regulated the protein levels of fibronectin 1, Slug, cyclin A2, cyclin B1, P57, and interferon-induced transmembrane 1 via ATIC. ATIC may be a valuable predictor of prognosis and a potential therapeutic target for UTUC.

Regional immunity of chicken adipose tissue responds to secondary immunity induced by Newcastle disease vaccine via promoting immune activation and weakening lipid metabolism.

Adipose tissue (AT) is considered as a regional immune organ and plays an important role in the anti-infection immune response. However, the function and mechanism of chicken AT in response to secondary immune response remain poorly understood. Here, we used mRNA and microRNA (miRNA) sequencing technology to survey the transcriptomic landscape of chicken abdominal adipose tissue (AAT) during the first and second immunization with Newcastle disease virus (NDV) vaccine, and carried out bioinformatics analysis, such as Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis, protein-protein interaction (PPI) analysis, and miRNA-mRNA integrated analysis. The results indicated that chicken AAT actively responded to the secondary immune response. DNA replication and cytoskeleton regulation as the regulatory functions of immune activation changed significantly, and weakened lipid metabolism was an effective strategy for the secondary immunity. Mechanically, the regulatory network between the differentially expressed miRNAs (DEMs) and their targeted differentially expressed genes (DEGs), such as miR-206/miR-499-5p-nuclear receptor subfamily 4 group A member 3 (NR4A3)/methylsterol monooxygenase 1 (MSMO1) pathway, was one of the potential key mechanisms by which AAT responded to the secondary immune response. In conclusion, regional immunity of chicken AT responds to secondary immunity by promoting immune activation and weakening lipid metabolism, and this study can instruct future research on antiviral strategy.

Renalase Prevents Renal Fibrosis by Inhibiting Endoplasmic Reticulum Stress and Down-Regulating GSK-3ß/Snail Signaling.

Background: Treating renal fibrosis is crucial to delaying chronic kidney disease. The glycogen synthase kinase-3ß (GSK-3ß)/Snail pathway regulates renal fibrosis and Renalase can ameliorate renal interstitial fibrosis. However, it is not clear whether GSK-3ß/Snail signaling affects Renalase action. Here, we explored the role and mechanism of GSK-3ß/Snail in the anti-fibrosis action of Renalase. Materials and methods: We used mice with complete unilateral ureteral obstruction (UUO) and human proximal renal tubular epithelial (HK-2) cells with transforming growth factor-ß1 (TGF-ß1)-induced fibrosis to explore the role and regulatory mechanism of the GSK-3ß/Snail pathway in the amelioration of renal fibrosis by Renalase. Results: In UUO mice and TGF-ß1-induced fibrotic HK-2 cells, the expression of p-GSK-3ß-Tyr216/p-GSK-3ß-Ser9, GSK-3ß and Snail was significantly increased, and endoplasmic reticulum (ER) stress was activated. After Renalase supplementation, fibrosis was alleviated, ER stress was inhibited and p-GSK-3ß-Tyr216/p-GSK-3ß-Ser9, GSK-3ß and Snail were significantly down-regulated. The amelioration of renal fibrosis by Renalase and its inhibitory effect on GSK-3ß/Snail were reversed by an ER stress agonist. Furthermore, when an adeno-associated virus or plasmid was used to overexpress GSK-3ß, the effect of Renalase on delaying renal fibrosis was counteracted, although ER stress markers did not change. Conclusion: Renalase prevents renal fibrosis by down-regulating GSK-3ß/Snail signaling through inhibition of ER stress. Exogenous Renalase may be an effective method of slowing or stopping chronic kidney disease progression.

Stress-induced immunosuppression affecting immune response to Newcastle disease virus vaccine through "miR-155-CTLA-4" pathway in chickens.

MiR-155 and CTLA-4 are important factors involved in the regulation of immune function. However, there is no report about their involvement in function regulation of stress-induced immunosuppression affecting immune response. In this study, the chicken model of stress-induced immunosuppression affecting immune response (simulation with dexamethasone and immunization with Newcastle disease virus (NDV) attenuated vaccine) was established, then the expression characteristics of miR-155 and CTLA-4 gene were analyzed at several key time points during the processes of stress-induced immunosuppression affecting NDV vaccine immune response at serum and tissue levels. The results showed that miR-155 and CTLA-4 were the key factors involved in stress-induced immunosuppression and NDV immune response, whose functions involved in the regulation of immune function were different in different tissues and time points, and 2 day post immunization (dpi), 5dpi and 21dpi were the possible key regulatory time points. CTLA-4, the target gene of miR-155, had significant game regulation relationships between them in various tissues, such as bursa of Fabricius, thymus and liver, indicating that miR-155-CTLA-4 pathway was one of the main mechanisms of their involvement in the regulations of stress-induced immunosuppression affecting NDV immune response. This study can lay the foundation for in-depth exploration of miR-155-CTLA-4 pathway involved in the regulation of immune function.

High MRE11 Expression Level Predicts Poor Survival in Upper Tract Urothelial Carcinomas.

Upper tract urothelial carcinoma (UTUC) is an aggressive malignancy with characteristics of high metastasis and poor prognosis. There are some particularly different features of UTUC between the Asian and Western countries. Double-strand break repair protein MRE11 is a component of the MRN complex that is involved in the DNA repair pathway. Emerging studies have focused on the role of MRE11 in human malignancies with conflicting results. We aimed to establish the relationship between MRE11 expression and the oncological outcome of UTUC. This study retrospectively reviewed 150 patients who underwent radical nephroureterectomy with pathologically confirmed UTUC. Pathologic slides were reviewed, and clinical parameters were collected. An immunohistochemical study was performed, and the cytoplasmic and nuclear-staining results of UTUC were recorded. The expression of MRE11 was analyzed to identify correlations with various clinicopathological parameters, metastasis-free survival, and cancer-specific survival (CSS). MRE11 expression was significantly correlated with patients with a high pathologic stage ( P =0.001), perineural invasion ( P =0.015), and tumor necrosis ( P =0.034). Upon univariate analysis, a high MRE11 expression was associated with poor metastasis-free survival ( P =0.014, 95% CI 1.18, 4.38) and poor CSS ( P =0.001, 95% CI 2.45, 27.75). Upon multivariable analysis, a high MRE11 expression was associated with poor CSS ( P =0.019, 95% CI 1.28, 15.65). In summary, MRE11 expression could serve as a potential predictor of prognosis in patients with UTUC.

Circulating miR-155, a potential regulator of immune responses to different vaccines in chicken.

Vaccination is one of effective means to prevent viral infectious diseases in poultry. However, the functions of circulating miRNAs in immune response remain unknown. In this study, miR-155, a key factor in the regulation of immune function, was selected to study its expression, potential function and mechanism in the 12-day-old chicken immune responses to three vaccines (avian influenza virus inactivated vaccine, Newcastle disease virus attenuated vaccine and infectious bursal disease virus attenuated vaccine), respectively. The experiment aimed to explore the relationships between the expression levels of serum circulating miR-155 and immune responses. The results showed that the expression levels of serum circulating miR-155 were significantly different during the three immune responses, but had similarities at several time points post inoculation. 2 day post inoculation (dpi), 5dpi, and 21dpi were the possible common key time points of the three immune responses. Moreover, spleen (2dpi), bursa of Fabricius and cecal tonsil (5dpi), and liver (21dpi) were the possible key tissues associated with the differential expression levels of serum circulating miR-155. Bioinformatics analysis showed that several key target genes (such as KRAS, RAP1B, and RPS6KA3) of miR-155 possibly played a key role in immune function regulation through MAPK and mTOR signaling pathways. The study can lay the foundation for further studying the function and application of circulating miR-155 in chicken immune responses.

Stress-Induced Immunosuppression Affects Immune Response to Newcastle Disease Virus Vaccine via Circulating miRNAs.

Studies have shown that circulating microRNAs (miRNAs) are important players in the immune response and stress-induced immunosuppression. However, the function and mechanism of stress-induced immunosuppression affecting the immune response to the Newcastle disease virus (NDV) vaccine remain largely unknown. This study analyzed the changes of 15 NDV-related circulating miRNAs at different immune stages by qRT-PCR, aiming to explore the key timepoints, potential biomarkers, and mechanisms for the functional regulation of candidate circulating miRNAs under immunosuppressed conditions. The results showed that stress-induced immunosuppression induced differential expressions of the candidate circulating miRNAs, especially at 2 days post immunization (dpi), 14 dpi, and 28 dpi. In addition, stress-induced immunosuppression significantly affected the immune response to NDV vaccine, which was manifested by significant changes in candidate circulating miRNAs at 2 dpi, 5 dpi, and 21 dpi. The featured expressions of candidate circulating miRNAs indicated their potential application as biomarkers in immunity and immunosuppression. Bioinformatics analysis revealed that the candidate circulating miRNAs possibly regulated immune function through key targeted genes, such as Mg2+/Mn2+-dependent 1A (PPM1A) and Nemo-like kinase (NLK), in the MAPK signaling pathway. This study provides a theoretical reference for studying the function and mechanism of circulating miRNAs in immune regulation.

Stress-induced immunosuppression affecting avian influenza virus vaccine immune response through miR-20a-5p/NR4A3 pathway in chicken.

Stress-induced immunosuppression is one of the most common hazards in poultry intensive production, which often leads to vaccination failure and severe economic losses. At present, there is no report about the function and mechanism of circulating miRNA on stress-induced immunosuppression affecting immune response. In this study, the changes of circulating miR-20a-5p under stress-induced immunosuppressive condition were analyzed by qRT-PCR, and the key time points, tissues and mechanisms for functional regulation of miR-20a-5p in the process of stress-induced immunosuppression affecting avian influenza virus (AIV) vaccine immune response were identified. The results showed that stress-induced immunosuppression down-regulated miR-20a-5p and further affected AIV vaccine immune response, in which 5 day post immunization (dpi) was a key time point, and the heart, lung, and proventriculus were the important tissues. The game relationship analysis between miR-20a-5p and its target nuclear receptor subfamily 4 group A member 3 (NR4A3) gene showed that "miR-20a-5p/NR4A3" pathway was the potential key mechanism of this process, especially for heart and lung. This study provides insights into the molecular mechanisms of stress-induced immunosuppression affecting immune response.

Synovial mesenchymal progenitor derived aggrecan regulates cartilage homeostasis and endogenous repair capacity.

Aggrecan is a critical component of the extracellular matrix of all cartilages. One of the early hallmarks of osteoarthritis (OA) is the loss of aggrecan from articular cartilage followed by degeneration of the tissue. Mesenchymal progenitor cell (MPC) populations in joints, including those in the synovium, have been hypothesized to play a role in the maintenance and/or repair of cartilage, however, the mechanism by which this may occur is unknown. In the current study, we have uncovered that aggrecan is secreted by synovial MPCs from healthy joints yet accumulates inside synovial MPCs within OA joints. Using human synovial biopsies and a rat model of OA, we established that this observation in aggrecan metabolism also occurs in vivo. Moreover, the loss of the "anti-proteinase" molecule alpha-2 macroglobulin (A2M) inhibits aggrecan secretion in OA synovial MPCs, whereas overexpressing A2M rescues the normal secretion of aggrecan. Using mice models of OA and cartilage repair, we have demonstrated that intra-articular injection of aggrecan into OA joints inhibits cartilage degeneration and stimulates cartilage repair respectively. Furthermore, when synovial MPCs overexpressing aggrecan were transplanted into injured joints, increased cartilage regeneration was observed vs. wild-type MPCs or MPCs with diminished aggrecan expression. Overall, these results suggest that aggrecan secreted from joint-associated MPCs may play a role in tissue homeostasis and repair of synovial joints.

MicroRNA-375-3p Suppresses Upper Tract Urothelial Carcinoma Cell Migration and Invasion via Targeting Derlin-1.

Little is known regarding the molecular characterization of upper tract urothelial carcinoma (UTUC). Novel therapeutic targets and prognostic predictors are imminent. In the present study, we aim to examine the oncogenic function and molecular mechanism of Derlin-1 in UTUC. Derlin-1 overexpression is significantly associated with poor prognosis in patients with UTUC. In vitro, knockdown or over-expression of Derlin-1 markedly regulated UTUC cell invasion and migration. We further discovered miR-375-3p suppresses cell invasion and migration by inversely regulating Derlin-1 and blocking EMT in UTUC cells. Taking this together, miR-375-3p functions as a tumor suppressive microRNA by directly targeting Derlin-1 and blocking epithelial-mesenchymal transition (EMT) in UTUC.

Stress-induced immunosuppression increases levels of certain circulating miRNAs and affects the immune response to an infectious bursal disease virus vaccine in chickens.

Stress-induced immunosuppression can affect the immune effect of vaccine. However, the mechanism of stress-induced immunosuppression affecting immune response to infectious bursal disease virus (IBDV) vaccine in chicken is still unclear. In this study, thirteen IBDV related circulating miRNAs were selected to study their expressions, possible functions and mechanisms in dexamethasone (Dex)-induced immunosuppressed chicken vaccinated with IBDV attenuated vaccine. The experiment aimed to explore the relationship between the expressions of IBDV related circulating miRNAs and stress-induced immunosuppression. The quantitative real-time PCR (qRT-PCR) results showed that Dex-induced immunosuppression could induce the differential expressions of the candidate serum circulating miRNAs, especially on the 2nd, 5th, 7th and 28th day after dexamethasone treatment. Dex-induced immunosuppression could affect the immune response to the IBDV vaccine, which was possibly achieved by partially regulating the differential expressions of the IBDV related circulating miRNAs. Bioinformatics analysis showed that the candidate miRNAs could regulate the immune function mainly through targeting genes (such as CREB1 and MAPK1) in TGF-ß and MAPK signaling pathways. This study can provide a preliminary reference for further studying the function and mechanism of circulating miRNAs in immune regulation.

Silver Nanoparticle-Mediated Synthesis of Fluorescent Thiolated Gold Nanoclusters.

A new strategy using silver nanoparticles (Ag NPs) to synthesize thiolated Au NCs is demonstrated. The quasi-spherical Ag NPs serve as a platform, functioning as a reducing agent for Au (III) and attracting capping ligands to the surface of the Ag NPs. Glutathione disulfide (GSSG) and dithiothreitol (DTT) were used as capping ligands to synthesize thiolated Au NCs (glutathione-Au NCs and DTT-Au NCs). The glutathione-Au NCs and DTT-Au NCs showed red color luminance with similar emission wavelengths (630 nm) at an excitation wavelength of 354 nm. The quantum yields of the glutathione-Au NCs and DTT-Au NCs were measured to be 7.3% and 7.0%, respectively. An electrophoretic mobility assay showed that the glutathione-Au NCs moved toward the anode, while the DTT-Au NCs were not mobile under the electric field, suggesting that the total net charge of the thiolated Au NCs is determined by the charges on the capping ligands. The detection of the KSV values, 26 M-1 and 0 M-1, respectively, revealed that glutathione-Au NCs are much more accessible to an aqueous environment than DTT-Au NCs.

High Transaldolase 1 expression predicts poor survival of patients with upper tract urothelial carcinoma.

Upper tract urothelial carcinoma (UTUC) is a rare tumor with an incidence that varies greatly between Eastern and Western countries. Transaldolase 1 (TALDO1) is a rate-limiting enzyme of the pentose phosphate pathway. In humans, aberrant TALDO1 activity has been implicated in various autoimmune diseases and malignancies; however, the function of TALDO1 in UTUC has not been previously investigated. Here we evaluated the clinical significance of TALDO1 expression in 115 paraffin-embedded tumor samples from patients with UTUC using immunohistochemistry. Our results demonstrated that there was an association between high TALDO1 expression and advanced stage (P = 0.011), tumor size (P = 0.005), tumor location (P = 0.047), distant metastases (P = 0.023), local recurrence (P = 0.002), and cancer death (P = 0.003). Using univariate and multivariate analyses, we found that chemotherapy was an independent factor for bladder recurrence-free survival. Late stage (III/IV) and high TALDO1 expression were independent prognostic factors for progression-free and cancer-specific survival. In summary, increased TALDO1 expression in UTUC was significantly correlated with late stage, tumor size, tumor location, distant metastases, local recurrence, and cancer death. Therefore, high TALDO1 expression could be a predictor of poor survival in patients with UTUC. Further studies are necessary to investigate the role of TALDO1 in UTUC development.

MiR-375: A novel multifunctional regulator.

MiR-375, a primitively described beta cell-specific miRNA, is confirmed to function as multi-functional regulator in diverse typical cellular pathways according to the follow-up researches. Based on the existing studies, miR-375 can regulate many functional genes and ectopic expressions of miR-375 are usually associated with pathological changes, and its expression regulation mechanism is mainly related to promoter methylation or circRNA. In this review, the regulatory functions of miR-375 in immunity, such as its relevance with macrophages, T helper cells and autoimmune diseases were briefly discussed. Also, the functions of miR-375 involved in inflammation, development and virus replication were reviewed. Finally, the mechanisms and application prospects of miR-375 in cancers were analyzed. Studies show that the application of miR-375 as therapeutic target and biomarker has a broad developing space in future. We hope this paper can provide reference for its further study.

Immune function of miR-214 and its application prospects as molecular marker.

MicroRNAs are a class of evolutionary conserved non-coding small RNAs that play key regulatory roles at the post-transcriptional level. In recent years, studies have shown that miR-214 plays an important role in regulating several biological processes such as cell proliferation and differentiation, tumorigenesis, inflammation and immunity, and it has become a hotspot in the miRNA field. In this review, the regulatory functions of miR-214 in the proliferation, differentiation and functional activities of immune-related cells, such as dendritic cells, T cells and NK cells, were briefly reviewed. Also, the mechanisms of miR-214 involved in tumor immunity, inflammatory regulation and antivirus were discussed. Finally, the value and application prospects of miR-214 as a molecular marker in inflammation and tumor related diseases were analyzed briefly. We hope it can provide reference for further study on the mechanism and application of miR-214.

Nioella ostreopsis sp. nov., isolated from toxic dinoflagellate, Ostreopsis lenticularis.

A novel short-rod-shaped bacterial strain with poly-ß-hydroxybutyric acid granules inside, designated as Z7-4T, was isolated from a culture of a marine dinoflagellate with palytoxin-producing capacity, Ostreopsis lenticularis OS06, collected from the East China Sea. Cells of Z7-4T were Gram-stain-negative, non-motile, strictly aerobic, 0.9-1.2 µm wide and 2.0-3.9 µm long. Growth occurred in 1-4 % (w/v) NaCl, at 15-37 °C and at pH 5.0-10.0, with optimum growth in 3.5 % (w/v) NaCl, at 30 °C and at pH 7.0. Analysis of 16S rRNA gene sequence revealed that Z7-4T shared the highest 16S rRNA gene sequence similarities with Nioella aestuarii JCM 30752T (98.8 %), followed by Nioella sediminis KCTC 42144T (98.6 %) and Nioella nitratireducens KCTC 32417T (96.9 %). Phylogenetic analysis based on nearly complete 16S rRNA gene sequences revealed that Z7-4T clearly represented a member of the genus Nioella within the family Rhodobacteraceae. The respiratory quinone of Z7-4T was identified as Q-10. Polar lipids of Z7-4T were phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, three unidentified aminophospholipids and one unidentified phospholipid. The major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C16 : 0. The DNA G+C content of Z7-4T was 63.0 mol%. DNA-DNA hybridization values of the isolate against the closely related type strains were far below the 70 % limit for species delineation. The average nucleotide identity and in silico DNA-DNA genome hybridization relatedness between Z7-4T and the closely related members of the genus Nioella, N. sediminis KCTC 42144T and N. nitratireducens KCTC 32417T, were 91.1 and 46.3 %, and 79.3 and 19.4 %, respectively. On the basis of the results of polyphasic analysis, Z7-4T is proposed to represent a novel species of the genus Nioella, for which the name Nioella ostreopsis sp. nov. is proposed. The type strain of Nioella ostreopsis is Z7-4T (=KCTC 62459T=CCTCC AB 2017231T).

Haliea alexandrii sp. nov., isolated from phycosphere microbiota of the toxin-producing dinoflagellate Alexandrium catenella.

A Gram-negative, aerobic, non-motile, non-spore-forming and rod-shaped bacterium, named strain LZ-16-2T, was isolated from the phycosphere microbiota of the paralytic shellfish poisoning toxin-producing marine dinoflagellate Alexandrium catenella LZT09. Strain LZ-16-2T grew optimally at 28 °C at pH 6.5 and with 3 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain LZ-16-2T fell within the genus Haliea and was most closely related to Haliea salexigens DSM 19537T, with which the new isolate exhibited 98.5 % 16S rRNA gene sequence similarity. The major respiratory quinone was Q-8. The predominant cellular fatty acids were C17 : 1 ω8c, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), C17 : 1 ω6c, C11 : 0 3-OH and C17 : 0. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The average nucleotide identity and in silico DNA-DNA genome hybridization relatedness values between strain LZ-16-2T and its closest relative, H. salexigens DSM 19537T, were 92.8 and 55.1 %, respectively. The DNA G+C content was 61.3 mol%. Differential phenotypic properties and phylogenetic distinctiveness distinguished strain LZ-16-2T from all other members of the genus Haliea. On the basis of the polyphasic characterization, strain LZ-16-2T represents a novel species of the genus Haliea, for which the name Haliea alexandrii sp. nov. is proposed. The type strain is LZ-16-2T (=KCTC 62344T=CCTCC AB2017229T).