Structural superlubricity at the interface of penta-BN2.

Two-dimensional (2D) materials have been widely used as lubricants due to their weak interlayer interaction and low shear resistance for interlayer sliding. Composed entirely of five-membered rings, penta-BN2 monolayer has excellent thermal and mechanical stability, higher hardness and a negative Poisson's ratio. In this work, we investigate the frictional properties at both the commensurate and incommensurate contacting interfaces of penta-BN2 by adopting the molecular dynamics (MD) simulation method. Our calculations demonstrate robust superlubricity at the incommensurate contacting interface of penta-BN2. The ultra-low friction is explained by the potential energy surface (PES) fluctuations, interlayer binding energy and out-of-plane motion amplitude of the sliding layer. In addition, our calculations show that the anisotropy of friction at the commensurate contacting interface is more obvious compared with that at the incommensurate contacting interface. Finally, the influences of the size of the Moiré pattern, normal force, temperature and sliding velocity on the friction are examined. Our results show that 2D penta-BN2 is a promising solid lubricant, enriching the family of 2D lubrication materials.

Low-Temperature Regulates the Cell Structure and Chlorophyll in Addition to Cellulose Metabolism of Postharvest Red Toona sinensis Buds across Different Seasons.

Postharvest fibrosis and greening of Toona sinensis buds significantly affect their quality during storage. This study aimed to clarify the effects of low-temperature storage on postharvest red TSB quality harvested in different seasons. Red TSB samples were collected from Guizhou province, China, 21 days after the beginning of spring (Lichun), summer (Lixia), and autumn (Liqiu), and stored at 4 °C in dark conditions. We compared and analyzed the appearance, microstructure, chlorophyll and cellulose content, and expression levels of related genes across different seasons. The results indicated that TSB harvested in spring had a bright, purple-red color, whereas those harvested in summer and autumn were green. All samples lost water and darkened after 1 day of storage. Severe greening occurred in spring-harvested TSB within 3 days, a phenomenon not observed in summer and autumn samples. Microstructural analysis revealed that the cells in the palisade and spongy tissues of spring and autumn TSB settled closely during storage, while summer TSB cells remained loosely aligned. Xylem cells were smallest in spring-harvested TSB and largest in autumn. Prolonged storage led to thickening of the secondary cell walls and pith cell autolysis in the petioles, enlarging the cavity area. Chlorophyll content was higher in leaves than in petioles, while cellulose content was lower in petioles across all seasons. Both chlorophyll and cellulose content increased with storage time. Gene expression analysis showed season-dependent variations and significant increases in the expression of over half of the chlorophyll-related and cellulose-related genes during refrigeration, correlating with the observed changes in chlorophyll and cellulose content. This research provides valuable insights for improving postharvest storage and freshness preservation strategies for red TSB across different seasons.

Genome-Wide Identification and Expression Profiling of Potato (Solanum tuberosum L.) Universal Stress Proteins Reveal Essential Roles in Mechanical Damage and Deoxynivalenol Stress.

Universal stress proteins (USPs) play an important regulatory role in responses to abiotic stress. Most of the research related to USPs so far has been conducted on plant models such as Arabidopsis (Arabidopsis thaliana), rice (Oryza sativa L.), and cotton (Gossypium hirsutum L.). The potato (Solanum tuberosum L.) is one of the four major food crops in the world. The potato is susceptible to mechanical damage and infection by pathogenic fungi during transport and storage. Deoxynivalenol (DON) released by Fusarium can seriously degrade the quality of potatoes. As a result, it is of great significance to study the expression pattern of the potato StUSP gene family under abiotic stress conditions. In this study, a total of 108 USP genes were identified from the genome of the Atlantic potato, divided into four subgroups. Based on their genetic structure, the physical and chemical properties of their proteins and other aspects of their biological characteristics are comprehensively analyzed. Collinear analysis showed that the homologous genes of StUSPs and four other representative species (Solanum lycopersicum, Arabidopsis, Oryza sativa L., and Nicotiana attenuata) were highly conserved. The cis-regulatory elements of the StUSPs promoter are involved in plant hormones, environmental stress, mechanical damage, and light response. RNA-seq analysis showed that there are differences in the expression patterns of members of each subgroup under different abiotic stresses. A Weighted Gene Coexpression Network Analysis (WGCNA) of the central gene showed that the differential coexpression gene is mainly involved in the plant-pathogen response process, plant hormone signal transduction, and the biosynthesis process of secondary metabolites. Through qRT-PCR analysis, it was confirmed that StUSP13, StUSP14, StUSP15, and StUSP41 may be important candidate genes involved in the response to adversity stress in potatoes. The results of this study provide a basis for further research on the functional analysis of StUSPs in the response of potatoes to adversity stress.

Non-Isocyanate Urethane Acrylate Derived from Isophorone Diamine: Synthesis, Characterization and Its Application in 3D Printing.

In this paper, urethane-based acrylates (UA) were prepared via an environmentally friendly non-isocyanate route. Isophorone diamine (IPDA) reacted with ethylene carbonate (EC), producing carbamate containing amine and hydroxyl groups, which further reacted with neopentyl glycol diacrylate (NPGDA) by aza Michael addition, forming UA. The structures of the obtained intermediates and UA were characterized by 1H NMR and electrospray ionization high-resolution mass spectrometry (ESI-HRMS). The photopolymerization kinetics of UA were investigated by infrared spectroscopy. The composite with obtained UA can be UV cured quickly to form a transparent film with a tensile strength of 21 MPa and elongation at break of 16%. After UV curing, the mono-functional urethane acrylate was copolymerized into the cross-linked network in the form of side chains. The hydroxyl and carbamate bonds on the side chains have high mobility, which make them easy to form stronger dynamic hydrogen bonds during the tensile process, giving the material a higher tensile strength and elongation at break. Therefore, the hydrogen bonding model of a cross-linked network is proposed. The composite with UA can be 3D printed into models.

Photochemical Degradation of the New Nicotine Pesticide Acetamiprid in Water.

Acetamiprid is a novel nicotinic pesticide widely used in modern agriculture because of its low toxicity and specific biological target properties. The objective of this study was to understand the photolysis pattern of acetamiprid in the water column and elucidate its degradation products and mechanism. It was observed that acetamiprid exhibited different photolysis rates under different light source conditions in pure water, with ultraviolet > fluorescence > sunlight; furthermore, its photolysis half-life ranged from 17.3 to 28.6 h. In addition, alkaline conditions (pH 9.0) accelerated its photolysis rate, which increased with pH. Using gas chromatography-mass spectrometry, five direct photolysis products generated during the exposure of acetamiprid to pure water were successfully separated and identified. The molecular structure of acetamiprid was further analyzed using density functional theory, and the active photodegradation sites of acetamiprid were predicted. The mechanism of the photolytic transformation of acetamiprid in water was mainly related to hydroxyl substitution and oxidation. Based on these findings, a comprehensive transformation pathway for acetamiprid was proposed.

Low LdMYB12 expression contributes to petal spot deficiency in Lilium davidii var. unicolor.

Petal spots are widespread in plants, they are important for attracting pollinators and as economic traits in crop breeding. However, the genetic and developmental control of petal spots has seldom been investigated. To further clarify the development of petal spots formation, we performed comparative transcriptome analysis of Lilium davidii var. unicolor and Lilium davidii petals at the full-bloom stage. In comparison with the parental species L. davidii, petals of the lily variety L. davidii var. unicolor do not have the distinct anthocyanin spots. We show that among 7846 differentially expressed genes detected, LdMYB12 was identified as a candidate gene contributing to spot formation in lily petals. The expression level of LdMYB12 in the petals of L. davidii was higher than that in L. davidii var. unicolor petals. Moreover, overexpression of LdMYB12 led to the appearance of spots on the petals of L. davidii var. unicolor, accompanied by increased expression of anthocyanin synthesis-related genes. Taken together, these results indicate that abnormal expression of LdMYB12 contributes to petal spot deficiency in L. davidii var. unicolor.

Debilitation of Galleria mellonella hemocytes using CytCo a cytolytic-like protein derived from the entomopathogen Conidiobolus obscurus.

Cytolytic (Cyt)-like genes are present in both pathogenic bacteria and fungi. Bacterial Cyt proteins can destroy insect midgut epithelial cells after ingestion by hosts and some of them have been developed as biopesticides; however, few studies have investigated their functions in fungal pathogens. This study investigated the effects of a Cyt-like protein (CytCo) derived from Conidiobolus obscurus (Entomophthoromycotina) on the hemocytes of the greater wax moth Galleria mellonella larvae. The results showed a significant decline in hemocyte viability after treatment with CytCo in vivo or in vitro. The hemocyte density in the hemolymph was reduced by 65.2% and 50.2% after 12 h in vivo and 6 h in vitro treatments, respectively. Apoptosis/necrosis tests using fluorescence microscopy demonstrated that CytCo-treated hemocytes displayed apoptosis, and many of them also showed necrosis after 6 h in vitro treatment. Based on transcriptome analysis, several genes involved in the programmed cell death signaling pathway were upregulated in the CytCo-treated hemocytes. Meanwhile, the differentially expressed genes related to energy production, signal transduction, transcription regulation, and melanization were upregulated, demonstrating activated immune responses; those putatively related to hemocyte adhesion were downregulated, possibly in response to the reduction of hemocytes in hemolymph. In conclusion, CytCo as a virulence factor, could irreversibly incapacitate host hemocytes, playing an important role in debilitating insect immunity. This novel insecticidal protein holds a potential to develop biopesticide for controlling agroforestry pests.

Enhancement of Upconversion Luminescence by the Construction of a 3Yb-Er-Hf Sublattice Energy Cluster and Surface Defect Elimination.

Nanotetragonal LiYF4:RE (Tm,Er,Ho) is a kind of excellent upconversion luminescence (UCL) material potentially used in many fields, while the enhancement of UC emission and regulation of luminescence lifetime are still a challenge. Herein, a strategy was reported to enhance UCL performance with the aid of the construction of a 3Yb-Er-Hf sublattice energy cluster with the introduction of Hf4+ and the interception of surface defect fluorescence quenching. UCL was obviously decreased by Hf4+ doping without surface defect elimination, but after the interception of surface defect quenching, UCL was dramatically enhanced more than 300-fold with an Er3+/Hf4+ mole ratio of 1:1. The contribution of UCL enhancement by the construction of a 3Yb-Er-Hf sublattice energy cluster is about 1.5 times of the sample without energy cluster construction. Interestingly, the lifetime of UCL can also be regulated by this strategy. According to the results of systematical microstructure analyses and UCL performance behaviors examined by X-ray powder diffraction (XRD), small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), nuclear magnetic resonance (NMR), and fluorescence spectrophotometry (FS) methods, the possible mechanism of UCL enhancement was proposed. This work may be an inspiration for researchers to design and develop high-performance UCL nanomaterials.

Regulation pore size distribution for facilitating malachite green removal on carbon foam.

Malachite green (MG) is widely used as a textile dye and an aquacultural biocide, and become a serious pollution of drink water, but effectually isolating and removing it from wastewater are still a challenge. Here we report a new strategy to prepare a carbon foam with tunable pore size distribution by a one-pot lava foam process. We find that uniform micropore size is beneficial to the formation of C-OH coordination on the pore surface, increasing MG adsorption rates via H+ ionization. As a result, carbon foam with uniform pore size distribution demonstrates an optimum MG removal efficiency of 1812 mg g-1 and a higher partition coefficient of 3.02 mg g-1 µM-1, which is twice that of carbon foams with irregular pore size distribution. The adsorption of MG onto these adsorbents was found to be an endothermic monolayer chemical adsorption process, and the Gibbs free energy of adsorption process was decreased obviously by regulating micropore size distribution. The experiment results are in good agreement with pseudo-second-order kinetic and Langmuir isotherm models. Revealed the pore size distribution was the critical factor of MG removal by carbon foam. It should be and inspiration for the design and development of highly efficiency adsorbents for dyes removal.

Muriiphilus fusiformis gen. nov., sp. nov., a novel non-marine bacterium belonging to the Roseobacter group, and reclassification of Maritimibacter lacisalsi (Zhong et al. 2015) as Muriicola lacisalsi gen. nov., comb. nov.

An aerobic, Gram-stain-negative, non-sporulating, flagellated and spindle-like bacterium, designated HY14T, was isolated from a pickle-processing factory wastewater sample. The isolate chemoheterotrophically grew at 4-42 °C (optimum, 35 °C) and pH 5.5-9.0 (optimum, pH 6.0-6.5). Salt was required for growth (0.5-12 % NaCl, w/v). A deep brown and water-soluble uncharacterized pigment was produced when grown in certain media. The predominant fatty acids (>5 %) included C16 : 0, C18 : 1 ω7c, 11-methyl C18 : 1 ω7c and C19 : 0 cyclo ω8c. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, two unidentified aminolipids, two unidentified phospholipids, two unidentified glycolipids and five unknown lipids. The major isoprenoid quinone was ubiquinone-10. Pairwise alignment based on 16S rRNA gene sequences indicated that strain HY14T had the highest sequence similarity to genera Maritimibacter (95.61-96.05 %) and Boseongicola (95.82 %). Phylogenetic analysis based on core genome illustrated that strain HY14T formed a monophyletic lineage with members of the genus Maritimibacter in the clade of the Roseobacter group in the family Rhodobacteraeceae. The core-gene average amino acid identity used to define bacterial genera by a threshold of 60-80 % was calculated to be 68.56-76.5 % between HY14T and closely related taxa. Several genomic characteristics, such as carrying two RuBisCO-mediated pathways and different osmoprotectant transport pathways, exhibited the genotypic discrepancies of strain HY14T. Based on the polyphasic taxonomic characterization, strain HY14T is considered to represent a novel species of a novel genus belonging to the family Rhodobacteraeceae, for which the name Muriiphilus fusiformis gen. nov., sp. nov. is proposed. The type strain is HY14T (=CGMCC 1.15973T=KCTC 52499T). Maritimibacter lacisalsi (Zhong et al. 2015) is considered to diverge from Maritimibacter alkaliphilus at the genus level, and should be reassigned as a novel genus, for which the name Muriicola lacisalsi gen. nov., comb. nov. is proposed.

Differential Expression Pattern of Pathogenicity-Related Genes of Ralstonia pseudosolanacearum YQ Responding to Tissue Debris of Casuarina equisetifolia.

Ralstonia solanacearum species complex (RSSC) contains a group of destructive plant pathogenic bacteria, causing bacterial wilt of >200 species of crops and trees, such as Casuarina equisetifolia, worldwide. RSSC can survive in the soil environment for a long time and start infection after activation by host plants. This study conducted a transcriptome analysis on the expression pattern of the pathogenicity-related genes of a new isolated RSSC strain YQ (Ralstonia pseudosolanacearum phylotype I-16) in response to C. equisetifolia cladophyll (a branch of a stem that resembles and functions as a leaf) and root debris under in vitro culture. The cladophyll debris induced more genes up-regulated than the root debris, including pathogenicity-related genes involved in motility, effectors, type III secretion systems, quorum sensing, and plant cell wall degradation. Besides, many differentially expressed genes were related to transcriptional regulator such as cyclic dimeric guanosine monophosphate. Moreover, the cultures with cladophyll debris induced a faster wilting in bioassays, and the cell swimming was enhanced by cladophyll exudate. C. equisetifolia cladophylls could activate the expression of pathogenicity-related genes of strain YQ and accelerate infection. Our findings suggest that litterfall management in C. equisetifolia forests, or even other plantations, should receive attention to prevent the induction of bacterial wilt disease caused by RSSC.

LINC01006 facilitates cell proliferation, migration and invasion in prostate cancer through targeting miR-34a-5p to up-regulate DAAM1.

BACKGROUND: Prostate cancer (PCa) is a kind of malignancy occurring in the prostate gland. Substantial researches have proved the major role of long noncoding RNAs (lncRNAs) in PCa. However, the role of long intergenic non-protein coding RNA 1006 (LINC01006) in PCa has not been investigated yet. METHODS: RT-qPCR was used to examine the expression levels of LINC01006 and its downstream targets. The function of LINC01006 in PCa was tested by in vitro and in vivo assays. With application of RNA pull down, RNA immunoprecipitation (RIP) and luciferase reporter assays, the interaction among LINC01006, miR-34a-5p and disheveled associated activator of morphogenesis 1 (DAAM1) were verified. RESULTS: LINC01006 expression presented high in PCa cell lines. LINC01006 silencing suppressed cell proliferative, migratory, invasive capacities while accelerated apoptotic rate. Besides, LINC01006 knockdown also suppressed tumor growth and metastasis in vivo. Furthermore, miR-34a-5p, a tumor suppressor in PCa, was sponged by LINC01006. Moreover, DAAM1 was targeted by miR-34a-5p and promoted PCa progression. More intriguingly, rescue assays suggested that the inhibitory effect of LINC01006 knockdown on PCa development was offset by DAAM1 overexpression. CONCLUSIONS: LINC01006 promoted PCa progression by sponging miR-34a-5p to up-regulate DAAM1, providing a novel target for PCa therapy.

Quality control of bedside DR in neonatal chest radiography using a chest stabilization device and its clinical application.

BACKGROUND: To develop a method for movement control during radiation exposure and to improve image quality of bedside thoracic DR in neonates. METHODS: Total 60 cases of neonates' thoracic DR X-ray images, which were taken before and after neonates' movement control, were compared and analyzed. X-ray exposure was set at 47 kV/1.4 mAs for all films that were taken without movement control, while various exposure conditions were used based on the neonate's body weight when the neonate's movement was controlled. RESULTS: The radiation dose of X-ray exposure was significantly lower after neonates' movement control (7.32 ± 0.20 µGy) than that before the movement control (24.20 ± 0.82 µGy, P <  0.05), and it was decreased most dramatically in the neonates with lowest body weight (70%). After neonates' movement control, image quality was significantly improved (44 cases out of 60, 73.3%) compared to that before movement control (only 5 out 60, 8.3%, P <  0.05). There was no significant difference in the score of image background noise before and after movement control (P <  0.05). CONCLUSION: Movement control with simple device could not only significantly improve the image quality, but also remarkably reduce radiation exposure dose.

Effect of B vitamins supplementation on cardio-metabolic factors in patients with stable coronary artery disease: A randomized double-blind trial.

BACKGROUND AND OBJECTIVES: This study aimed to evaluate whether B vitamins supplementation would improve dyslipidemia, alleviate inflammatory state of patients with stable coronary artery disease (SCAD). METHODS AND STUDY DESIGN: We conducted a randomized, double-blind, 12-week, placebo-controlled trial involving adults with SCAD, and who were randomly divided into B vitamins group (folic acid and VB-6) and control group (placebo tablet). Blood tests had also been performed at baseline and endpoint. RESULTS: After 12 weeks of intervention, B vitamins supplementation significantly improved the concentration of serum TG, TC and HDL-C (p<0.05). Changes of serum homocysteine in B vitamins treatment were significantly different compared to placebo by the multivariate-adjusted analysis (3.02±2.35 vs 1.55±1.58 p<0.001). Meanwhile, the levels of IL-1ß and IL-10, significant difference were observed between two groups after adjustment for confounding factors. CONCLUSIONS: Supplementation with B vitamins significantly improves lipid metabolism, alleviate inflammation and serum homocysteine concentration in patients with SCAD.

Manipulating the transmission of vector beam with spatially polarized atomic ensemble.

Vector beams (VBs) with potential applications are successfully utilized in many fields as light sources with a spatially-varying polarization profile in recent years. Here, we study the transmission of a VB by manipulating atomic polarization via the optical pumping effect. By using hybridly and radially polarized beams as pump and probe beams in a counter-propagating configuration, we observe a four-petal pattern intensity distribution of probe beam, and the four-petal pattern rotates with the polarization state orientation of the pump beam. The results show a polarization dependent absorption in the atomic media. We experimentally demonstrate the absorption characteristics under different polarization combinations of pump and probe beams. The Jones matrix method is used to explain this phenomenon and the simulations are consistent with the experimental observation. Our results may provide a sound foundation for applications in optical manipulation and quantum information in atomic ensembles.

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).

Alkalilacustris brevis gen. nov., sp. nov., isolated from a soda lake.

A Gram-stain-negative, aerobic, non-pigmented and short-rod-shaped bacterium, designated 34079T, was isolated from a water sample of a soda lake in Jilin, a province of China. Strain 34079T grew at 10-50 °C (optimum, 35 °C), pH 7-10 (optimum, pH 8.0-8.5). NaCl was required for growth at the concentration range 1-10.0 % (w/v), with an optimum at 2.5-4 % (w/v). Chemotaxonomic analysis indicated that the sole respiratory quinone was Q-10. The predominant cellular fatty acids (>5 %) were summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c) and C16 : 0. The major polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, three unidentified amino lipids, one unidentified amino phosphoglycolipid, one phosphoglycolipid, one unidentified glycolipid, three unidentified phospholipids and two unidentified lipids. The DNA G+C content was 65.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 34079T formed a distinct lineage in the clade of the family 'Rhodobacteraceae' with the highest sequence similarity of 96.1 % to Pararhodobacter aggregans, followed by Rhodobaca bogoriensis DSM 18756T (95.7 %) and Roseibaca ekhonensis DSM 11469T (94.7 %). The distinct biochemical, chemotaxonomic and phylogenetic differences from the previously described taxa supported that strain 34079T represents a novel species of a new genus, for which the name Alkalilacustris brevis gen. nov., sp. nov. is proposed. The type strain is 34079T (=KCTC 62428T=MCCC 1K03493T).

Maripseudobacter aurantiacus gen. nov., sp. nov., a novel member of the family Flavobacteriaceae isolated from a sedimentation basin.

A Gram-stain negative, orange-pigmented, aerobic, non-motile and ovoid- to rod-shaped bacterial strain, designated CDA4T, was isolated from a sediment sample collected from the sedimentation basin of a mariculture farm in Zhejiang province, China. The temperature range for growth of strain CDA4T was 15-40 °C, wirrth an optimum at 35 °C. The pH range for growth was 6.0-8.5, with an optimum around pH 7.5. NaCl was required for growth at the concentration range 0.5-5.0 % (w/v), with an optimum at 2.0 % (w/v). Chemotaxonomic analysis indicated that the main respiratory quinone was menaquinone 6 (MK-6), the predominant cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G, unknown ECL 13.565 and iso-C17 : 0 3-OH, and the major polar lipids were phosphatidylethanolamine, two unidentified lipids, two unidentified phospholipids and four unidentified aminolipids. The genomic DNA G+C content of strain CDA4T was 38.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CDA4T formed a distinct lineage in the clade of the family Flavobacteriaceae. Based on the polyphasic taxonomic characterization, strain CDA4T is considered to represent a novel species of a new genus, for which the name Maripseudobacter aurantiacus gen. nov., sp. nov. is proposed. The type strain of the type species is CDA4T (=KCTC 52409T=MCCC 1K03210T).

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.

Isolation and Complete Genome Sequence of Algibacter alginolytica sp. nov., a Novel Seaweed-Degrading Bacteroidetes Bacterium with Diverse Putative Polysaccharide Utilization Loci.

The members of the phylum Bacteroidetes are recognized as some of the most important specialists for the degradation of polysaccharides. However, in contrast to research on Bacteroidetes in the human gut, research on polysaccharide degradation by marine Bacteroidetes is still rare. The genus Algibacter belongs to the Flavobacteriaceae family of the Bacteroidetes, and most species in this genus are isolated from or near the habitat of algae, indicating a preference for the complex polysaccharides of algae. In this work, a novel brown-seaweed-degrading strain designated HZ22 was isolated from the surface of a brown seaweed (Laminaria japonica). On the basis of its physiological, chemotaxonomic, and genotypic characteristics, it is proposed that strain HZ22 represents a novel species in the genus Algibacter with the proposed name Algibacter alginolytica sp. nov. The genome of strain HZ22, the type strain of this species, harbors 3,371 coding sequences (CDSs) and 255 carbohydrate-active enzymes (CAZymes), including 104 glycoside hydrolases (GHs) and 18 polysaccharide lyases (PLs); this appears to be the highest proportion of CAZymes (∼7.5%) among the reported strains in the class Flavobacteria Seventeen polysaccharide utilization loci (PUL) are predicted to be specific for marine polysaccharides, especially algal polysaccharides from red, green, and brown seaweeds. In particular, PUL N is predicted to be specific for alginate. Taking these findings together with the results of assays of crude alginate lyases, we prove that strain HZ22(T) can completely degrade alginate. This work reveals that strain HZ22(T) has good potential for the degradation of algal polysaccharides and that the structure and related mechanism of PUL in strain HZ22(T) are worth further research.