DL-3-n-Butylphthalide Ameliorates Post-stroke Emotional Disorders by Suppressing Neuroinflammation and PANoptosis.

Post-stroke emotional disorders such as post-stroke anxiety and post-stroke depression are typical symptoms in patients with stroke. They are closely associated with poor prognosis and low quality of life. The State Food and Drug Administration of China has approved DL-3-n-butylphthalide (NBP) as a treatment for ischemic stroke (IS). Clinical research has shown that NBP alleviates anxiety and depressive symptoms in patients with IS. Therefore, this study explored the role and molecular mechanisms of NBP in cases of post-stroke emotional disorders using network pharmacology and experimental validation. The results showed that NBP treatment significantly increased the percentage of time spent in the center of the middle cerebral artery occlusion (MCAO) rats in the open field test and the percentage of sucrose consumption in the sucrose preference test. Network pharmacology results suggest that NBP may regulate neuroinflammation and cell death. Further experiments revealed that NBP inhibited the toll-like receptor 4/nuclear factor kappa B signaling pathway, decreased the level of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1ß, and interleukin-6, and M1-type microglia markers (CD68, inducible nitric oxide synthase), and reduced the expression of PANoptosis-related molecules including caspase-1, caspase-3, caspase-8, gasdermin D, and mixed lineage kinase domain-like protein in the hippocampus of the MACO rats. These findings demonstrate that the mechanisms through which NBP ameliorates post-stroke emotional disorders in rats are associated with inhibiting neuroinflammation and PANoptosis, providing a new strategy and experimental basis for treating post-stroke emotional disorders.

Mangiferin alleviated poststroke cognitive impairment by modulating lipid metabolism in cerebral ischemia/reperfusion rats.

INTRODUCTION: Mangiferin is a Chinese herbal extract with multiple biological activities. Mangiferin can penetrate the blood‒brain barrier and has potential in the treatment of nervous system diseases. These findings suggest that mangiferin protects the neurological function in ischemic stroke rats by targeting multiple signaling pathways. However, little is known about the effect and mechanism of mangiferin in alleviating poststroke cognitive impairment. METHODS: Cerebral ischemia/reperfusion (I/R) rats were generated via middle cerebral artery occlusion. Laser speckle imaging was used to monitor the cerebral blood flow. The I/R rats were intraperitoneally (i.p.) injected with 40 mg/kg mangiferin for 7 consecutive days. Neurological scoring, and TTC staining were performed to evaluate neurological function. Behavioral experiments, including the open field test, elevated plus maze, sucrose preference test, and novel object recognition test, were performed to evaluate cognitive function. Metabolomic data from brain tissue with multivariate statistics were analyzed by gas chromatography‒mass spectrometry and liquid chromatography‒mass spectrometry. RESULTS: Mangiferin markedly decreased neurological scores, and reduced infarct areas. Mangiferin significantly attenuated anxiety-like and depression-like behaviors and enhanced learning and memory in I/R rats. According to the metabolomics results, 13 metabolites were identified to be potentially regulated by mangiferin, and the differentially abundant metabolites were mainly involved in lipid metabolism. CONCLUSIONS: Mangiferin protected neurological function and relieved poststroke cognitive impairment by improving lipid metabolism abnormalities in I/R rats.

A Study on the Properties of Composite Modified Mortar with Styrene-Butadiene Rubber Latex and Silica Fume.

To solve the problem of the poor abrasion resistance of concrete pavement surface mortar, this study substituted cement with equal amounts of styrene-butadiene rubber (SBR) latex and silica fume (SF) to investigate the effects of organic/inorganic material composite modification on the fluidity, drying shrinkage, mechanical properties, and abrasion resistance of cement mortar. Also in this study, the microstructure, product, and pore structure characteristics of the composite modified cement mortar were investigated using scanning electron microscope (SEM), X-Ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and the Brunauer-Emmett-Teller (BET) method. This research found that the sole substitution of SF negatively impacted the mortar's fluidity and drying shrinkage yet enhanced its mechanical strength and abrasion resistance; the incorporation of SBR latex improved fluidity, reduced shrinkage, and increased flexural strength but adversely affected the compressive strength of the mortar. Additionally, the enhancement of the mortar's abrasion resistance with SBR latex was significantly greater than that with SF. When SBR latex and SF were used together as substitutes, the latex struggled to offset the negative impact of SF on mortar fluidity but effectively reduced shrinkage; SF compensated for the detrimental effect of the latex on compressive strength. Moreover, the primary role in enhancing the mortar's abrasion resistance was played by the latex. Microscopic tests showed that SBR latex and SF could increase the content of calcium silicate hydrate (C-S-H) gel, inhibit the formation of ettringite (AFt) and reduce carbonation, refine the pore size of cement mortar, and effectively improve the microstructure of mortar.

CK2 negatively regulates the extinction of remote fear memory.

Cognitive behavioral therapy, rooted in exposure therapy, is currently the primary approach employed in the treatment of anxiety-related conditions, including post-traumatic stress disorder (PTSD). In laboratory settings, fear extinction in animals is a commonly employed technique to investigate exposure therapy; however, the precise mechanisms underlying fear extinction remain elusive. Casein kinase 2 (CK2), which regulates neuroplasticity via phosphorylation of its substrates, has a significant influence in various neurological disorders, such as Alzheimer's disease and Parkinson's disease, as well as in the process of learning and memory. In this study, we adopted a classical Pavlovian fear conditioning model to investigate the involvement of CK2 in remote fear memory extinction and its underlying mechanisms. The results indicated that the activity of CK2 in the medial prefrontal cortex (mPFC) of mice was significantly upregulated after extinction training of remote cued fear memory. Notably, administration of the CK2 inhibitor CX-4945 prior to extinction training facilitated the extinction of remote fear memory. In addition, CX-4945 significantly upregulated the expression of p-ERK1/2 and p-CREB in the mPFC. Our results suggest that CK2 negatively regulates remote fear memory extinction, at least in part, by inhibiting the ERK-CREB pathway. These findings contribute to our understanding of the underlying mechanisms of remote cued fear extinction, thereby offering a theoretical foundation and identifying potential targets for the intervention and treatment of PTSD.

A comparative study of the neuroprotective effects of dl-3-n-butylphthalide and edaravone dexborneol on cerebral ischemic stroke rats.

INTRODUCTION: DL-3-n-butylphthalide (NBP) and edaravone dexborneol (Eda-Dex) are two promising reagents for stroke treatment. However, the impacts of NBP and Eda-Dex on poststroke mental deficits are still poorly understood. In this study, we aimed to investigate and compare the influences of NBP and Eda-Dex on neurological function and cognitive behavior in rats with ischemic stroke. METHODS: An ischemic stroke model was established by middle cerebral artery occlusion (MCAO). After peritoneal administration of the drugs, the rats were subjected to neurological deficit evaluation, cerebral blood flow (CBF) assays, cerebral infarct area evaluations or behavioral tests. Brain tissues were collected and further analyzed by enzyme-linked immunosorbent assay (ELISA), western blotting or immunohistochemistry. RESULTS: NBP and Eda-Dex significantly decreased the neurological score, reduced the cerebral infarct area and improved CBF. Behavioral changes as assessed in the sucrose preference test, novel object recognition test, and social interaction test were significantly alleviated by NBP and Eda-Dex in rats with ischemic stroke. Moreover, NBP and Eda-Dex significantly suppressed inflammation by targeting the nuclear factor kappa-B/inducible nitric oxide synthase (NF-κB/iNOS) pathway and significantly inhibited oxidative stress by targeting the kelch-1ike ECH-associated protein l/nuclear factor erythroid 2-related factor 2 (Keap1/Nrf2) pathway. In addition, NBP and Eda-Dex distinctly suppressed the activation of microglia and astrocytes and improved neuronal viability in the ischemic brain. CONCLUSIONS: NBP and Eda-Dex improved neurological function and alleviated cognitive disorders in rats with ischemic stroke by synergistically inhibiting inflammation and oxidative stress.

DNA hypomethylation and upregulated LINC00518 acts as a promoter and biomarker in head and neck squamous cell carcinoma.

Background: LINC00518 acts as an oncogene in several cancers, but its function in head and neck squamous cell carcinoma (HNSCC) remains unclear. Materials & methods: The expression and methylation status of LINC00518 were analyzed by reviewing public databases. The ceRNA network and the relationship with tumor immunity of LINC00518 were analyzed using online tools and in vitro studies. Results: Upregulated LINC00518 was associated with poor clinicopathological characteristics of HNSCC. Silencing LINC00518 significantly inhibited the migration of HNSCC cells. LINC00518 might positively regulate HMGA2 via the ceRNA mechanism. Additionally, LINC00518 was negatively correlated with various immune cells and immunotherapy markers. Moreover, the upregulation of LINC00518 in HNSCC may be due to DNA hypomethylation. Conclusion: LINC00518 may be a potential biomarker and therapeutic target for HNSCC.

Pexidartinib (PLX3397) through restoring hippocampal synaptic plasticity ameliorates social isolation-induced mood disorders.

Social behavior is essential for the well-being and survival of individuals. However, social isolation is a serious public health issue, especially during the COVID-19 pandemic, affecting a significant number of people worldwide, and can lead to serious psychological crises. Microglia, innate immune cells in the brain, are strongly implicated in the development of psychiatry. Although many microglial inhibitors have been used to treat depression, there is no literature report on pexidartinib (PLX3397) and social isolation. Herein, we adopted PLX3397 to investigate the role of microglia in the modulation of social isolation. Our results found that social isolation during adolescence caused depressive-like, but not anxiety-like behavior in mice in adulthood, with enhanced expression of the microglial marker Iba1 in the hippocampus. In addition, treatment with PLX3397 reduced the expression of the microglial marker Iba1, decreased the mRNA expression of IL-1ß, increased the mRNA expression of Arg1, elevated the protein levels of DCX and GluR1 and restored the dendritic spine branches and density, ultimately mitigating depressive-like behavior in mice. These findings suggest that inhibition of microglia in the hippocampus could ameliorate mood disorders in mice, providing a new perspective for the treatment of psychiatric disorders such as depression.

DL-3-n-butylphthalide (NBP) alleviates poststroke cognitive impairment (PSCI) by suppressing neuroinflammation and oxidative stress.

Currently, the recovery of cognitive function has become an essential part of stroke rehabilitation. DL-3-n-butylphthalide (NBP) is a neuroprotective reagent and has been used in stroke treatment. Clinical studies have confirmed that NBP can achieve better cognitive outcomes in ischemic stroke patients than in healthy controls. In this study, we aimed to investigate the influences of NBP on cognitive function in an ischemic reperfusion (I/R) rat model. Our results showed that NBP profoundly decreased neurological scores, reduced cerebral infarct areas and enhanced cerebral blood flow (CBF). NBP potently alleviated poststroke cognitive impairment (PSCI) including depression-like behavior and learning, memory and social cognition impairments, in I/R rats. NBP distinctly suppressed the activation of microglia and astrocytes and improved neuron viability in the ischemic brain. NBP inhibited the expression of inflammatory cytokines, including interleukin-6 (IL-6), interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α), by targeting the nuclear factor kappa B/inducible nitric oxide synthase (NF-κB/iNOS) pathway and decreased cerebral oxidative stress factors, including reactive oxygen species (ROS) and malondialdehyde (MDA), by targeting the kelch like ECH associated protein 1/nuclear factor-erythroid 2 p45-related factor 2 (Keap1/Nrf2) pathway in the ischemic brain. The current study revealed that NBP treatment improved neurological function and ameliorated cognitive impairment in I/R rats, possibly by synergistically suppressing inflammation and oxidative stress.

Bursaphelenchus xylophilus detection and analysis system based on CRISPR - Cas12.

Pine wilt disease is caused by the pine wood nematode (Bursaphelenchus xylophilus) and leads to wilting and death of pines. It is one of the most damaging diseases of pines worldwide. Therefore, accurate and rapid detection methods are of great importance for the control of B. xylophilus. Traditional detection methods have some problems, such as being time-consuming and requiring expensive instruments. In this study, the loop-mediated isothermal amplification (LAMP) and clustered regularly interspaced short palindromic repeats (CRISPR) were used to establish a set of intelligent detection and analysis system for B. xylophilus, called LAMP-CRISPR/Cas12a analysis, which integrated field sampling, rapid detection and intelligent control analysis. The process can be completed within 1 hour, from sample pretreatment and detection to data analysis. Compared with the single LAMP method, the LAMP-CRISPR/Cas12a assay uses species-specific fluorescence cleavage to detect target amplicons. This process confirms the amplicon identity, thereby avoiding false-positive results from non-specific amplicons, and the large amounts of irrelevant background DNA do not interfere with the reaction. The LAMP-CRISPR/Cas12a assay was applied to 46 pine wood samples and the samples carrying B. xylophilus nematodes were successfully identified. To meet the needs of different environments, we designed three methods to interpret the data: 1) naked eye interpretation; 2) lateral flow biosensor assay; and 3) integrated molecular analysis system to standardize and intellectualize the detection process. Application of the B. xylophilus detection and analysis system will reduce the professional and technical requirements for the operating environment and operators and help to ensure the accuracy of the detection results, which is important in grass-root B. xylophilus detection institutions.

Hippocampal LASP1 ameliorates chronic stress-mediated behavioral responses in a mouse model of unpredictable chronic mild stress.

Substantial evidence has revealed that abnormalities in synaptic plasticity play important roles during the process of depression. LASP1 (LIM and SH3 domain protein 1), a member of actin-binding proteins, has been shown to be associated with the regulation of synaptic plasticity. However, the role of LASP1 in the regulation of mood is still unclear. Here, using an unpredictable chronic mild stress (UCMS) paradigm, we found that the mRNA and protein levels of LASP1 were decreased in the hippocampus of stressed mice and that UCMS-induced down-regulation of LASP1 was abolished by chronic administration of fluoxetine. Adenosine-associated virus-mediated hippocampal LASP1 overexpression alleviated the UCMS-induced behavioral results of forced swimming test and sucrose preference test in stressed mice. It also restored the dendritic spine density, elevated the levels of AKT (a serine/threonine protein kinase), phosphorylated-AKT, insulin-like growth factor 2, and postsynaptic density protein 95. These findings suggest that LASP1 alleviates UCMS-provoked behavioral defects, which may be mediated by an enhanced dendritic spine density and more activated AKT-dependent LASP1 signaling, pointing to the antidepressant role of LASP1.

Acute restraint stress alters food-foraging behavior in rats: Taking the easier Way while suffered.

Stress can influence decision-making in humans from many cognitive perspectives, while the underlying neurobiological mechanism remains incompletely understood. Food-foraging is a rodent behavior involving strategic possessing of nutritional supply in social context; experimental model of this behavior could help explore the effect of stress on decision-making and the brain mechanism thereof. In the present study, the influence of stress on food-foraging behavior was assessed in rats using an open field choosing paradigm wherein food collection (standard food or sweet food) were associated with social competition (with or without a rat in the cage). Acute restraint stress (ARS) was induced by placing the rat in a plastic restrainer for 2 h before food-foraging behavioral tests, with the effect of stress also determined biochemically and immunohistochemically. Restraint stressed rats showed anxiety-like behavior and elevation of serum corticosterone (CORT) and epinephrine (EPI) relative to controls. Both restraint and control animals preferred sugared food. However, the former group tended to forage food from a cage not occupied by a conspecific rat, whereas the control rats preferred to obtain food from the cage with a social competitor. Thus, the total amount of food foraged and eaten are reduced in the restrained rats than in controls. While the restraint animals had normal social interaction with other rats, they displayed enhanced social agonistic behavior. In brain examination, ARS attenuated the increase in immunolabeling and protein levels of c-fos, p-CREB, p-ERK1/2 in the anterior cingulate cortex (ACC) observed in control animals in association with food-foraging. These results indicate that restraint stressed rats tend to forage food by taking the advantage of a less competitive opportunity. Mechanistically, this decision-making alternative appears to be mediated through a neuronal deactivation in the ACC. The current findings provide novel insights into neuronal processing of decision-making behavior under the influence of stress.

The Role of miR-150 in Stress-Induced Anxiety-Like Behavior in Mice.

Stress plays a crucial role in several psychiatric disorders, including anxiety. However, the underlying mechanisms remain poorly understood. Here, we used acute stress (AS) and chronic restraint stress (CRS) models to develop anxiety-like behavior and investigate the role of miR-150 in the hippocampi of mice. Corticosterone levels as well as glutamate receptors in the hippocampus were evaluated. We found that anxiety-like behavior was induced after either AS or CRS, as determined by the open-field test (OFT) and elevated plus-maze test (EPM). Increased corticosterone levels were observed in the blood of AS and CRS groups, while the expression of miR-150 mRNA in the hippocampus was significantly decreased. The expressions of GluN2A, GluR1, GluR2, and V-Glut2 in the hippocampus were decreased after either AS or CRS. Hippocampal GAD67 expression was increased by AS but not CRS, and GluN2B expression was decreased by CRS but not AS. Adult miR-150 knockout mice showed anxiety-like behavior, as assessed by the OFT and EPM. The expressions of GluN2A, GluN2B, GluR1, and GluR2 were also downregulated, but the expression of V-Glut2 was upregulated in the hippocampi of miR-150 knockout mice compared with wild-type mice. Interestingly, we found that the miR-150 knockout mice showed decreased dendrite lengths, dendrite branchings, and numbers of dendrite spines in the hippocampus compared with wild-type mice. These results suggest that miR-150 may influence the synaptic plasticity of the hippocampus and play a significant role in stress-induced anxiety-like behavior in adult mice.

Wohlfahrtiimonas populi sp. nov., isolated from symptomatic bark of a Populus × euramericana canker.

A Gram-stain-negative, facultatively anaerobic, motile, bacterial strain, 34C10-3-10T, was isolated from symptomatic bark tissue of a Populus ×euramericana canker. The isolate could grow between 10 and 37 °C, at pH 5 to 11, and in 0-3 % (w/v) NaCl. The strain was oxidase and catalase positive. The ubiquinone of strain 34C10-3-10T was Q-8. The polar lipid profile of strain 34C10-3-10T included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phospholipid, phosphatidylmonomethylethanolamine, phosphatidylserine; the major fatty acids were C18 : 1ω7c, C14 : 0 and C16 : 1ω7c/C16 : 1ω6c. The average nucleotide identity (ANI) values between strain 34C10-3-10T and the type strains of reference species Wohlfahrtiimonas chitiniclastica S5T and Wohlfahrtiimonas larvae KBL006T were lower than the proposed species boundary cut-off for ANI. The DNA G+C content was 37.1 mol%. Based on phenotypic and genotypic characteristics, strain 34C10-3-10T represents a novel species of genus Wohlfahrtiimonas; the name Wohlfahrtiimonas populi sp. nov. is proposed. The type strain is 34C10-3-10T (=CFCC 12747T=KCTC 52796T).

Paracoccus aerius sp. nov., isolated from air.

Strain 011410T, isolated from air at the foot of Xiangshan Mountain, Beijing, China, was Gram-reaction-negative, facultatively anaerobic, oval-shaped, motile with two flagella and catalase- and oxidase-positive. Growth of strain 011410T was observed at 4-41 °C (optimum, 30 °C), at pH 4.5-10.0 (optimum, pH 8.0) and at salinities of 0-10 % (w/v) NaCl (optimum, 0-2 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 011410T was a member of the genus Paracoccus and was related most closely to Paracoccus aestuarii B7T (96.62 % similarity) and Paracoccus sediminis CMB17T (96.48 % similarity). The major fatty acid was identified as C18 : 1ω7c, with smaller amounts of C18 : 0, C10 : 0 3-OH and summed feature 2 (C14 : 0 3-OH and/or iso-C16 : 1 I). The predominant respiratory quinone was ubiquinone-10 (Q-10), with Q-9 as a minor component. Polar lipid analysis indicated the presence of diphosphatidylglycerol, phosphatidylglycerol, one unknown phosphoglycolipid, five unknown phospholipids, one unknown aminolipid, one unknown glycolipid and two unknown polar lipids. The DNA G+C content of the strain was 63.5 mol%. On the basis of the data from this polyphasic characterization, strain 011410T represents a novel species, for which the name Paracoccus aerius sp. nov. is proposed. The type strain is 011410T (=CFCC 14285T=KCTC 42845T).

Leucobacter corticis sp. nov., isolated from symptomatic bark of Populus × euramericana canker.

A Gram-stain-positive, aerobic, non-motile, rod-shaped bacterial strain, designated 2C-7T, was isolated from symptomatic bark of a Populus × euramericana canker. Growth occurred between 10 and 37 °C and between pH 6 and 10, with optimal growth at 30 °C and pH 7.0-8.0. Growth was present under 0-8 % (w/v) salinity conditions (optimum 1-2 %). Growth occurred in the presence of 10 mM chromium (Cr6+). The major fatty acids (≥10 %) of the novel strain were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phospholipid, glycolipid and two unknown lipids. The major respiratory quinone was menaquinone MK-11. The cell wall amino acids were 2,4-diaminobutyric acid, alanine, glutamic acid and glycine. Strain 2C-7T was most similar to Leucobacter celer subsp. celer NAL101T (97.2 % 16S rRNA gene sequence similarity), 'Leucobacter kyeonggiensis' F3-P9T (97.1 %) and Leucobacter chromiireducens L-1T (97.1 %). In the phylogenetic tree, the isolate formed a single distinct branch separate from those of L. celer subsp. celer NAL101T, 'L. kyeonggiensis' F3-P9T and Leucobacter chironomi DSM 19883T. The DNA-DNA hybridization values between the novel strain and the reference strains were lower than the accepted bacterial threshold level of 70 % for species delineation. The DNA G+C content of strain 2C-7T was 70.0 mol%. Based on the data, strain 2C-7T represents a novel species in the genus Leucobacter, for which the name Leucobacter corticis sp. nov. is proposed. The type strain is 2C-7T (=CFCC 11901T=KCTC 39643T).

Description of Altererythrobacter aerius sp. nov., isolated from air, and emended description of the genus Altererythrobacter.

A Gram-stain-negative, yellow-pigmented, ovoid to rod-shaped, strictly aerobic bacterial strain, designated 100921-2T, was isolated from air at the foot of Xiangshan Mountain. Phylogenetic and phenotypic analysis of the organism revealed that the isolate belongs to the genus Altererythrobacter. Strain 100921-2T showed high 16S rRNA gene sequence similarity (96.01-94.70 %) to other type strains of the genus Altererythrobacter, with the highest similarity to Altererythrobactermarensis MSW-14T. Growth of strain 100921-2T was observed at 4-50 °C (optimum, 30 °C), at pH 4.5-10.0 (optimum, pH 7.0) and at salinities of 0-10 % (w/v) NaCl (optimum 0-0.5 %). The major fatty acids were C18 : 1ω7c (27.8 %), C17 : 1ω6c (23.1 %), 11-methyl C18 : 1ω7c(11.9 %), summed feature 3 (9.1 %) and C15 : 0 2-OH (7.9 %). The predominant respiratory quinone was ubiquinone-10 (Q-10). Polar lipid analysis indicated the presence of diphosphatidylglycerol, sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, two unknown phospholipids, five unknown polar lipids and two unknown glycolipids. The DNA G+C content of the type strain was 67.5 mol%. On the basis of the data from the polyphasic characterization, strain 100921-2T represents a novel species, for which the name Altererythrobacter aerius sp. nov. is proposed. The type strain is 100921-2T (=CFCC 14287T=KCTC 42844T).

Populibacterium corticicola gen. nov., sp. nov., a member of the family Jonesiaceae, isolated from symptomatic bark of Populus × euramericana canker.

Four Gram-stain-positive, aerobic, motile bacterial strains were isolated from the bark tissue of Populus × euramericana canker. Growth occurred between 10 and 37 °C and at pH 6-10, with optimal growth at 28-30 °C and pH 7.0-8.0. Growth occurred at 0-3 % (w/v) salinity. The strains were positive for oxidase and catalase activity. The major fatty acids were anteiso-C15 : 0 and C16 : 0. The phospholipid profiles contained diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, two phospholipids and five glycolipids. The peptidoglycan type was A4α, which is based on l-Lys-d-Ser-d-Asp. The DNA G+C content was 58.5 mol%. Based on 16S rRNA gene sequence analysis, as well as physiological and biochemical characteristics, the strains are considered to represent a novel species of a new genus in the family Jonesiaceae. The name proposed is Populibacterium corticicola gen. nov., sp. nov. The type strain of Populibacterium corticicola is 2D-4T (=CFCC 11886T=KCTC 33576T).

Sphingobacterium populi sp. nov., isolated from bark of Populus × euramericana.

A Gram-stain-negative, aerobic, non-motile bacterial strain, 7Y-4T, was isolated from bark tissue of Populus × euramericana. The isolate was able to grow between 10 and 37 °C, with optimal growth occurring at 28-30 °C. Strain 7Y-4T was positive for oxidase and catalase activities, but did not reduce nitrite from nitrate. Positive reactions were observed for the activities of ß-galactosidase, urease and ß-glucosidase, but negative reactions for the activities of gelatinase and the production of indole, acetoin and H2S. Citrate was not utilized. The major fatty acids of strain 7Y-4T are iso-C15 : 0 (28.6 %), C16 : 1ω7c/C16 : 1ω6c (31.8 %) and iso-C17 : 0 3-OH (23.3 %).The major polar lipids of the novel isolate include phosphatidylethanolamine, three unknown phospholipids (PL1-3) and six unknown lipids (L1-6), and the predominant menaquinone is MK-7. The DNA G+C content is 41.7 mol%. Analysis of 16S rRNA gene sequences revealed that the novel isolate shared the greatest sequence similarity with Sphingobacterium hotanense XH4T (93.50 %). On the basis of phenotypic and genotypic characteristics, strain 7Y-4T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium populi is proposed. The type strain is 7Y-4T (=CFCC 11742T=KCTC 42247T).

Leucobacter populi sp. nov. isolated from a symptomatic bark of Populus × euramericana canker.

A Gram-stain positive, aerobic, non-motile, rod-shaped, oxidase-negative and catalase-positive bacterial strain, designated 06C10-3-11T, was isolated from the symptomatic bark of a Populus × euramericana canker. Growth occurred at 10-45 °C (optimum, 30 °C), pH 6-11 (optimum, pH 7.0-8.0), 0-7 % (w/v) NaCl (optimum, 0-1 %) and in the presence of 20 mM Cr (VI). The major fatty acids (≥10 %) of the novel strain were identified as anteiso-C15:0, anteiso-C17:0 and iso-C16:0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phospholipid, glycolipid and two unknown lipids. The strain contained the respiratory quinone MK-10 (71 %) as a major component and MK-11 (29 %) in lesser amounts. The cell wall amino acids were 2,4-diaminobutyric acid, alanine, glutamic acid and glycine. The genomic DNA G+C content of the type strain was 69.8 mol%. Phylogenetic analysis, based on 16S rRNA gene sequences, indicated that strain 06C10-3-11T belongs to the genus Leucobacter, showing the highest 16S rRNA gene sequence similarities with Leucobacter celer NAL101T (96.19 %), 'Leucobacter kyeonggiensis' F3-P9T (96.18 %), Leucobacter denitrificans M1T8B10T (96.10 %) and Leucobacter aridicollis CIP 108388T (96.06 %). The DNA G+C content of strain 06C10-3-11T was 69.8 mol%. Based on the molecular data and physiological and biochemical characteristics, strain 06C10-3-11T is considered to represent a novel species of the genus Leucobacter, for which the name Leucobacterpopuli sp. nov. is proposed. The type strain is 06C10-3-11T (= CFCC 12199T = KCTC 39685T).

Corticibacter populi gen. nov., sp. nov., a new member of the family Comamonadaceae, from the bark of Populus euramericana.

Three novel endophytic strains, designated 17B10-2-12T, 26C10-4-4 and D13-10-4-9, were isolated from the bark of Populus euramericana in Heze, Shandong Province, China. They were Gram-reaction-negative, aerobic, non-motile, short-rod-shaped, oxidase-positive and catalase-negative. A phylogenetic analysis of the 16S rRNA gene showed that the three novel strains clustered with members of the family Comamonadaceae and formed a distinct branch. The isolates shared 100 % similarities among themselves and had the highest sequence similarity with Xenophilus azovorans DSM 13620T (95.2 %) and Xenophilus arseniciresistens YW8T (95.0 %), and less than 95.0 % sequence similarities with members of other species. Their major fatty acids were C16 : 0, C17 : 0 cyclo, C18 : 1ω7c and C16 : 1ω7c/C16 : 1ω6c. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unknown aminophospholipids. The predominant quinone was ubiquinone-8 (Q-8). The DNA G+C content was 69.5­70.0 mol%. Based on data from a polyphasic taxonomy study, the three strains represent a novel species of a novel genus of the family Comamonadaceae, for which the name Corticibacter populi gen. nov., sp. nov. is proposed. The type strain is 17B10-2-12T ( = CFCC 12099T = KCTC 42091T).