[Establishing and verifying the threshold value of HLA mixed antigen reagent screening test results]

Objective: To establish the threshold value of human leukocyte antigen (HLA) mixed antigen reagent screening test results, and to verify it by HLA single antigen reagent confirmation test results. Methods: The results of 2 255 serum samples tested for HLA antibodies by HLA mixed antigen reagent in the department of HLA Laboratory, the First Affiliated Hospital of Soochow University from October 2017 to December 2021 were retrospectively analyzed. Among them, 1 139 samples were also tested by single antigen HLA Class-Ⅰ reagent and 1 116 samples were also tested by single antigen HLA Class-Ⅱ reagent. Based on the same antigens coated with both reagents, the Mean Fluorescence Intensity (MFI) and Nomalized Background ratio (NBG ratio) of 12 HLA Class-Ⅰ beads and 5 HLA Class-Ⅱ beads in the HLA mixed antigen reagent and the MFI of 77 anti-HLA class-Ⅰ antibodies and 35 anti-HLA class-Ⅱ antibodies detected by HLA single antigen reagent were recorded. The MFI and NBG ratio of HLA mixed antigen reagent beads in 1 139 or 1 116 samples were segmented according to the positive rate of antibodyies detected by the single antigen reagent corresponding to the antigens coated with each HLA mixed antigen reagent bead, and the results of the HLA mixed antigen screening test were verified by the HLA single antigen reagent confirmation test. Results: The threshold values of MFI and NBG ratio of HLA mixed antigen reagent's 17 beads were established. The MFI of No. 1 to No. 17 beads of HLA mixed antigen reagent ranged from 26.86 to 21 925.58, and the NBG ratio ranged from 0 to 434.65. According to the positive detection rate of HLA single antigen reagent corresponding to the coated antigens, the MFI and NBG ratio of the beads of HLA mixed antigen reagent were divided into positive interval, suspicious positive interval, suspicious negative interval and negative interval. The positive rates of anti-HLA class-Ⅰ antibodies by HLA mixed antigen reagent and single antigen HLA Class-Ⅰ reagent were 87.5% (997/1 139) and 66.3% (755/1 139). The positive rates of anti-HLA class-Ⅱ antibodies were 63.4% (707/1 116) and 44.9% (501/1 116). In the samples with suspicious negative, suspicious positive and positive results of HLA class-Ⅰ、Ⅱ antibodies detected by HLA mixed antigen reagent, the positive detection rates of single antigen HLA Class-Ⅰ reagent were 14.9% (17/114), 41.3% (145/351) and 91.3% (590/646), respectively. The positive detection rates of single antigen HLA Class-Ⅱ reagent were 15.5% (58/375), 26.5% (81/306) and 88.8% (356/401), respectively. Conclusions: In this study, the threshold values of MFI and NBG ratio of HLA mixed antigen reagent screening test are established, and the threshold values are verified by the results of HLA single antigen reagent confirmation test. HLA mixed reagent screening test can be used for screening of HLA antibodies, and if necessary, it should be combined with HLA single antigen confirmatory test for clinical detection of HLA antibodies.

Corrigendum: Pangenome analysis of the genus Herbiconiux and proposal of four new species associated with Chinese medicinal plants

[This corrects the article DOI: 10.3389/fmicb.2023.1119226.].

Environmental distribution and genomic characteristics of Solirubrobacter, with proposal of two novel species

Solirubrobacter spp. were abundant in soil samples collected from deserts and other areas with high UV radiation. In addition, a novel Solirubrobacter species, with strain CPCC 204708T as the type, was isolated and identified from sandy soil sample collected from the Badain Jaran Desert of the Inner Mongolia autonomous region. Strain CPCC 204708T was Gram-stain positive, rod-shaped, non-motile, non-spore-forming, and grew optimally at 28-30°C, pH 7.0-8.0, and in the absence of NaCl. Analysis of the 16S rRNA gene sequence of strain CPCC 204708T showed its identity within the genus Solirubrobacter, with highest nucleotide similarities (97.4-98.2%) to other named Solirubrobacter species. Phylogenetic and genomic analyses indicated that the strain was most closely related to Solirubrobacter phytolaccae KCTC 29190T, while represented a distinct species, as confirmed from physiological properties and comparison. The name Solirubrobacter deserti sp. nov. was consequently proposed, with CPCC 204708T (= DSM 105495T = NBRC 112942T) as the type strain. Genomic analyses of the Solirubrobacter spp. also suggested that Solirubrobacter sp. URHD0082 represents a novel species, for which the name Candidatus "Solirubrobacter pratensis" sp. nov. was proposed. Genomic analysis of CPCC 204708T revealed the presence of genes related to its adaptation to the harsh environments of deserts and may also harbor genes functional in plant-microbe interactions. Pan-genomic analysis of available Solirubrobacter spp. confirmed the presence of many of the above genes as core components of Solirubrobacter genomes and suggests they may possess beneficial potential for their associate plant and may be important resources for bioactive compounds.

Corrigendum: Geminicoccus flavidas sp. nov. and Geminicoccus harenae sp. nov., two IAA-producing novel rare bacterial species inhabiting desert biological soil crusts

[This corrects the article DOI: 10.3389/fmicb.2022.1034816.].

[Anticoagulation status and adherence in patients with atrial fibrillation hospitalized for ACS and the impact on 1-year prognosis: a multicenter cohort study]

Objective: For patients with atrial fibrillation (AF) complicated with acute coronary syndrome (ACS), both anticoagulant and antiplatelet therapy should be applied, but the use of anticoagulation therapy is still poor in these patients in China. The purpose of this study was to explore the status and adherence of antithrombotic therapy in AF patients with ACS and the impact on 1 year clinical outcomes. Methods: Patients with AF hospitalized for ACS were retrospectively included from 6 tertiary hospitals in China between July 2015 and December 2020. According to the use of anticoagulant drugs at discharge, patients were divided into two groups: anticoagulant treatment group and non-anticoagulant treatment group. Logistic regression model was used to analyze the main factors influencing the use of anticoagulant drugs in patients with atrial fibrillation complicated with ACS. Major adverse cardiac events (MACEs) were defined as all-cause death, non-fatal myocardial infarction or coronary revascularization, and ischemic stroke and Bleeding Academic Research Consortium (BARC) 3 bleeding events were also collected at 1 year after discharge. After propensity score matching, Cox proportional hazards models and Kaplan-Meier analysis were used to evaluate the effect of anticoagulant treatment and non-anticoagulant treatment on 1-year prognosis. The patients were divided into different groups according to whether anticoagulation was performed at discharge and follow-up, and the sensitivity of the results was analyzed. Results: A total of 664 patients were enrolled, and 273 (41.1%) were treated with anticoagulant therapy, of whom 84 (30.8%) received triple antithrombotic therapy, 91 (33.3%) received double antithrombotic therapy (single antiplatelet combined with anticoagulant), and 98 (35.9%) received single anticoagulant therapy. Three hundred and ninety-one (58.9%) patients were treated with antiplatelet therapy, including 253 (64.7%) with dual antiplatelet therapy and 138 (35.3%) with single antiplatelet therapy. After 1∶1 propensity score matching between the anticoagulant group and the non-anticoagulant group, a total of 218 pairs were matched. Multivariate logistic regression analysis showed that history of diabetes, HAS-BLED score≥3, and percutaneous coronary intervention were predictors of the absence of anticoagulant therapy, while history of ischemic stroke and persistent atrial fibrillation were predictors of anticoagulant therapy. At 1-year follow-up, 218 patients (79.9%) in the anticoagulant group continued to receive anticoagulant therapy, and 333 patients (85.2%) in the antiplatelet group continued to receive antiplatelet therapy. At 1-year follow-up, 36 MACEs events (13.2%) occurred in the anticoagulant group, and 81 MACEs events (20.7%) in the non-anticoagulant group. HR values and confidence intervals were calculated by Cox proportional risk model. Patients in the non-anticoagulant group faced a higher risk of MACEs (HR=1.802, 95%CI 1.112-2.921, P=0.017), and the risk of bleeding events was similar between the two group (HR=0.825,95%CI 0.397-1.715, P=0.607). Conclusions: History of diabetes, HAS-BLED score≥3, and percutaneous coronary intervention are independent factors for the absence of anticoagulant therapy in patients with AF complicated with ACS. The incidence of MACEs, death and myocardial infarction is lower in the anticoagulant group, and the incidence of bleeding events is similar between the two groups. The risk of bleeding and ischemia/thrombosis should be dynamically assessed during follow-up and antithrombotic regiments should be adjusted accordingly.

Three new isocoumarin analogues from an endolichenic fungus Aspergillus flavus CPCC 400810

Five isocoumarin derivatives including three new compounds, aspermarolides A-C (1-3), and two known analogues, 8-methoxyldiaporthin (4) and diaporthin (5) were obtained from the culture extract of Aspergillus flavus CPCC 400810. The structures of these compounds were elucidated by spectroscopic methods. The double bond geometry of 1 and 2 were assigned by the coupling constants. The absolute configuration of 3 was determined by electronic circular dichroism experiment. All compounds showed no cytotoxic activities against the two human cancer cells HepG2 and Hela.

Pangenome analysis of the genus Herbiconiux and proposal of four new species associated with Chinese medicinal plants

Five Gram-stain-positive, aerobic, non-motile actinobacterial strains designated as CPCC 205763T, CPCC 203386T, CPCC 205716T, CPCC 203406T, and CPCC 203407 were obtained from different ecosystems associated with four kinds of Chinese traditional medicinal plants. The 16S rRNA gene sequences of these five strains showed closely related to members of the genus Herbiconiux of the family Microbacteriaceae, with the highest similarities of 97.4-99.7% to the four validly named species of Herbiconiux. In the phylogenetic trees based on 16S rRNA gene sequences and the core genome, these isolates clustered into the clade of the genus Herbiconiux within the lineage of the family Microbacteriaceae. The overall genome relatedness indexes (values of ANI and dDDH) and the phenotypic properties (morphological, physiological and chemotaxonomic characteristics) of these isolates, readily supported to affiliate them to the genus Herbiconiux, representing four novel species, with the isolates CPCC 203406T and CPCC 203407 being classified in the same species. For which the names Herbiconiux aconitum sp. nov. (type strain CPCC 205763T = I19A-01430T = CGMCC 1.60067T), Herbiconiux daphne sp. nov. (type strain CPCC 203386T = I10A-01569T = DSM 24546T = KCTC 19839T), Herbiconiux gentiana sp. nov. (type strain CPCC 205716T = I21A-01427T = CGMCC 1.60064T), and Herbiconiux oxytropis sp. nov. (type strain CPCC 203406T = I10A-02268T = DSM 24549T = KCTC 19840T) were proposed, respectively. In the genomes of these five strains, the putative encoding genes for amidase, endoglucanase, phosphatase, and superoxidative dismutase were retrieved, which were classified as biosynthetic genes/gene-clusters regarding plant growth-promotion (PGP) functions. The positive results from IAA-producing, cellulose-degrading and anti-oxidation experiments further approved their potential PGP bio-functions. Pangenome analysis of the genus Herbiconiux supported the polyphasic taxonomy results and confirmed their bio-function potential.

Characterization of three Stenotrophomonas strains isolated from different ecosystems and proposal of Stenotrophomonas mori sp. nov. and Stenotrophomonas lacuserhaii sp. nov

Stenotrophomonas spp. have primarily been reported as non-pathogenic, plant-probiotic bacteria, despite the presence of some opportunistic human pathogens in the genus. Here, three Gram-stain negative, rod-shaped, non-spore-forming bacteria, designated as strains CPCC 101365^T, CPCC 101269^T, and CPCC 101426 were isolated from surface-sterilized medicinal plant roots of a mulberry plant in Chuxiong of the Yunnan Province, freshwater from Erhai Lake in the Yunnan Province, and sandy soils in the Badain Jaran desert in Inner Mongolia Autonomous Region, China, respectively. The 16S rRNA gene sequences analysis of these isolates in comparison with sequences from the GenBank database indicated that they belong to the genus Stenotrophomonas, with nucleotide similarities of 96.52-99.92% to identified Stenotrophomonas members. Phylogenetic analysis based on 16S rRNA gene and genome sequences confirmed that the isolates are members of the genus Stenotrophomonas. Values for genomic average nucleotide identity (ANI; <95%) and digital DNA-DNA hybridization (dDDH; < 70%) indicated that strains CPCC 101365^T and CPCC 101269^T were well-differentiated from validly described Stenotrophomonas species, while strain CPCC 101426 shared high ANI (97.7%) and dDDH (78.3%) identity with its closest phylogenetic neighbor, Stenotrophomonas koreensis JCM 13256^T. The three genomes were approximately 3.1-4.0 Mbp in size and their G + C content ranged in 66.2-70.2%, with values slightly differing between CPCC 101365^T (3.4 Mbp; 70.2%), CPCC 101269^T (4.0 Mbp; 66.4%), and CPCC 101426 (3.1 Mbp; 66.2%). Genes encoding enzymes involved in the biosynthesis of indole-3-acetic acid (IAA) and siderophores were identified in the genomes of the three isolates, suggesting that these strains might serve roles as plant-growth promoting microorganisms. The polar lipid fractions of the three isolates primarily comprised diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), and phosphatidylethanolamine (PE). The predominant cellular fatty acid was iso-C₁₅: ₀, with moderate amounts of antesio-C_{15: 0}, iso-C_{11: 0}, iso C_{17: 1} ɷ9c/C_{16: 0} 10-methyl, iso-C_{14: 0}, and C_{16: 1} ɷ7c/C_{16: 1} ɷ6c. These results indicated that polyphasic characteristics of strains CPCC 101365^T and CPCC 101269^T differed from other identified Stenotrophomonas species and that strain CPCC 101426 was affiliated with the species Stenotrophomonas koreensis. Accordingly, two novel species of the genus Stenotrophomonas were consequently proposed, corresponding to Stenotrophomonas mori sp. nov. (type strain CPCC 101365^T = DY006^T = KCTC 82900^T) and Stenotrophomonas lacuserhaii sp. nov. (type strain CPCC 101269^T = K32^T = KCTC 82901^T).

Highlights

Members of the genus Stenotrophomonas, and particularly Stenotrophomonas maltophilia, are opportunistic human pathogens, but not enough research has evaluated the identification of environmental Stenotrophomonas spp. However, most Stenotrophomonas spp. serves as plant-probiotic bacteria.In this study, we obtained and characterized three Stenotrophomonas strains from different ecosystems. Based on phenotypic differences, chemotaxonomic properties, ANI and dDDH identity values, and phylogenetic analyses, two novel Stenotrophomonas species are proposed for the strains identified here. The encoding genes related to plant-growth promotion in the genomes of the newly recovered Stenotrophomonas spp. were retrieved. Follow-on experiments confirmed that these strains produced the important plant hormone IAA. Thus, these Stenotrophomonas spp. could considerably contribute to shaping and maintaining ecological stability in plant-associated environments, particularly while acting as plant-probiotic microorganisms.

Shinella lacus sp. nov., a novel microcystin-degrading alphaproteobacterium containing the bla carbapenemase gene

A Gram-stain-negative, rod-shaped, microcystin-degrading bacterium, designated as CPCC 100929T, was isolated from a fresh water reservoir in Sichuan Province, PR China. This isolate grew well at 4–37 °C and pH 6.0–8.0, with optimal growth at 28–32 °C and pH 7.0, respectively. The major cellular fatty acids were C18:1 ω7c/C18:1 ω6c, C16:0, C18:1 ω7c 11-methyl and C19:0 cyclo ω8c. The predominant respiratory quinone was Q-10. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine and phosphatidylcholine were detected in the polar lipids extraction. The 16S rRNA gene sequence of strain CPCC 100929T was closely related to those of members of the genus Shinella , with the highest similarity of 98.6 % to Shinella zoogloeoides DSM 287T and 97.4–98.4 % with other identified Shinella members. In the phylogenetic trees based on 16S rRNA gene sequences and the core-genes analysis, strain CPCC 100929T was included within the clade of the genus Shinella . The values of average nucleotide identity (81.4–86.7 %) and digital DNA–DNA hybridization (25.4–44.6 %) between strain CPCC 100929T and other Shinella species were all below the thresholds for bacterial species delineation, respectively. The genomic DNA G+C content of strain CPCC 100929T was 63.6 %. The genomic sequence analysis indicated that this species contained genes encoding peroxidase, bla carbapenemase and the key enzyme for microcystin bio degradation, as well as rich carbohydrate-active enzyme coding genes, which might endow the micro-organism with properties to adapt to diverse environments. Based on its phenotypic and genetic properties, we propose that strain CPCC 100929T (=T1A350T=KCTC 72957T) is the type strain of a novel species with the name Shinella lacus sp. nov.

Geminicoccus flavidas sp. nov. and Geminicoccus harenae sp. nov., two IAA-producing novel rare bacterial species inhabiting desert biological soil crusts

Two Gram-staining negative strains (CPCC 101082T and CPCC 101083T) were isolated from biological sandy soil crusts samples collected from Badain Jaran desert, China. Both isolates were heterotrophic phototroph, could produce indole-3-acetic acid. The 16S rRNA gene sequences of these two strains were closely related to the members of the family Geminicoccaceae, showing high similarities with Geminicoccus roseus DSM 18922T (96.9%) and Arboricoccus pini B29T1T (90.1%), respectively. In phylogenetic tree based on 16S rRNA gene sequences, strain CPCC 101082T and CPCC 101083T formed a robust distinct clade with Geminicoccus roseus DSM 18922T within the family Geminicoccaceae, which indicated that these two isolates could be classified into the genus Geminicoccus. The growth of strain CPCC 101082T occurred at 15-42°C and pH 4.0-10.0 (optima at 28-37°C and pH 6.0-8.0). The growth of strain CPCC 101083T occurred at 4-45°C and pH 4.0-10.0 (optima at 25-30°C and pH 6.0-8.0). The major cellular fatty acids of CPCC 101082T and CPCC 101083T contained C18:1 ω7c/C18:1 ω6c, cyclo-C19:0 ω8c, and C16:0. Q-10 was detected as the sole respiratory quinone. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, an unidentified phospholipid and an unidentified aminolipid were tested in the polar lipids profile. The genomes of the two isolates were characterized as about 5.9 Mbp in size with the G + C content of nearly 68%. The IAA-producing encoding genes were predicated in both genomes. The values of average nucleotide identity were 80.6, 81.2 and 92.4% based on a pairwise comparison of the genomes of strains CPCC 101082T and CPCC 101083T and Geminicoccus roseus DSM 18922T, respectively. On the basis of the genotypic, chemotaxonomic and phenotypic characteristics, the strains CPCC 101082T (=NBRC 113513T = KCTC 62853T) and CPCC 101083T (=NBRC 113514T = KCTC 62854T) are proposed to represent two novel species of the genus Geminicoccus with the names Geminicoccus flavidas sp. nov. and Geminicoccus harenae sp. nov.

Metabolites from the plant endophytic fungus Penicillium sp. CPCC 401423 and their cytotoxic activity against MIA PaCa-2 cells

Twenty-two metabolites were isolated from Penicillium sp. CPCC 401423 cultured on rice. The structures of all compounds were elucidated mainly by MS and NMR analysis as well as the necessary CD experimental evidence, of which penicillidione A (1), penicillidione B (2), (E)-4-[(4-acetoxy-3-methyl-2-butenyl)oxy]phenylacetic acid (3), (S)-2-hydroxy-2-{4-[(3-methyl-2-butenyl)oxy]phenyl} (4), (S)-4-(2,3-dihydroxy-3-methyl-butoxy)phenylacetic acid (5), (E)-4-[(3-carboxy-2-butenyl)oxy]benzoic acid (6), (Z)-4-[(4-hydroxy-3-methyl-2-butenyl)oxy]benzoic acid (7), open-cycled N-demethylmelearoride A (12), and penostatin M (16) were identified as new compounds. The cytotoxic activity against human pancreatic carcinoma cell line MIA PaCa-2a was detected. Among them, compounds 13-15 and 22 displayed significant cytotoxicity against MIA-PaCa-2 cells with IC₅₀ values of 8.9, 36.5, 31.8, and 22.3 µM, respectively (positive control gemcitabine IC₅₀ 65.0 µM).

[Singapore's healthy aging policy and implications for China]

Population ageing has become a major social issue of concern worldwide in recent years, with significant implications for national economic and social development. Globally, Singapore is one of the first countries to address ageing as a population issue and has implemented relatively well-developed initiatives to promote healthy ageing. Similar to China, Singapore has a sharp decline in the total fertility rate, resulting in changes in the population structure. This paper briefly introduces Singapore's healthy ageing measures, summarizes Singapore's practical measures and coping concepts in scientific research on ageing, healthcare programs for the elderly, elderly -friendly environment construction, artificial intelligence big data application, and puts forward that China should pay attention to the effectiveness of population growth incentive measures, pay attention to the scientific and technological response, increase the development and application of artificial intelligence, improve primary health care and long-term health care, and update scientific concepts.

Isolation, Characterization, and Antimicrobial Activity of Bacterial and Fungal Representatives Associated With Particulate Matter During Haze and Non-haze Days

Particulate matter (PM) has been a threat to the environment and public health in the metropolises of developing industrial countries such as Beijing. The microorganisms associated with PM have an impact on human health if they are exposed to the respiratory tract persistently. There are few reports on the microbial resources collected from PM and their antimicrobial activities. In this study, we greatly expanded the diversity of available commensal organisms by collecting 1,258 bacterial and 456 fungal isolates from 63 PM samples. A total of 77 bacterial genera and 35 fungal genera were included in our pure cultures, with Bacillus as the most prevalent cultured bacterial genus, Aspergillus, and Penicillium as the most prevalent fungal ones. During heavy-haze days, the numbers of colony-forming units (CFUs) and isolates of bacteria and fungi were decreased. Bacillus, Paenibacillus, and Chaetomium were found to be enriched during haze days, while Kocuria, Microbacterium, and Penicillium were found to be enriched during non-haze days. Antimicrobial activity against common pathogens have been found in 40 bacterial representatives and 1 fungal representative. The collection of airborne strains will provide a basis to greatly increase our understanding of the relationship between bacteria and fungi associated with PM and human health.

Properties of Modestobacter deserti sp. nov., a Kind of Novel Phosphate-Solubilizing Actinobacteria Inhabited in the Desert Biological Soil Crusts

Three Gram-stain-positive, aerobic, motile actinobacterial strains designated as CPCC 205119^T, CPCC 205215, and CPCC 205251 were isolated from different biological soil crust samples collected from Tengger Desert, China. The 16S rRNA gene sequence comparison of these three strains showed they had almost identical 16S rRNA genes, which were closely related to members of the family Geodermatophilaceae, with the highest similarities of 96.3–97.3% to the species of Modestobacter. In the phylogenetic tree based on 16S rRNA gene sequences, these isolates clustered into a subclade next to the branch containing the species of Modestobacter lapidis and Modestobacter multiseptatus, within the lineage of the genus Modestobacter. The comparative genomic characteristics (values of ANI, dDDH, AAI, and POCP) and the phenotypic properties (morphological, physiological, and chemotaxonomic characteristics) of these isolates readily supported to affiliate them to the genus Modestobacter as a single separate species. For which, we proposed that the isolates CPCC 205119^T, CPCC 205215, and CPCC 205251 represent a novel species of the genus Modestobacter as Modestobacter deserti sp. nov. CPCC 205119^T (=I12A-02624=NBRC 113528^T=KCTC 49201^T) is the type strain. The genome of strain CPCC 205119^T consisted of one chromosome (4,843,235bp) containing 4,424 coding genes, 48 tRNA genes, five rRNA genes, three other ncRNA genes, and 101 pseudogenes, with G+C content of 74.7%. The whole-genome sequences analysis indicated that this species contained alkaline phosphatase genes (phoA/phoD), phosphate transport-related genes (phoU, phnC, phnD, phnE, phoB, phoH, phoP, phoR, pitH, ppk, pstA, pstB, pstC, and pstS), trehalose-phosphate synthase gene (otsA), trehalose 6-phosphate phosphatase gene (otsB) and other encoding genes for the properties that help the microorganisms to adapt to harsh environmental conditions prevalent in deserts. Strains of this species could solubilize tricalcium phosphate [Ca₃(PO₄)₂] and phytin, assimilate pyrophosphate, thiophosphate, dithiophosphate, phosphoenol pyruvate, 2-deoxy-d-glucose-6-phosphate, and cysteamine-S-phosphate.

Anthraquinone analogues with inhibitory activities against influenza a virus from Polygonatum odoratum

Three anthraquinone analogues (1-3) were isolated by phytochemical work on EtOAc-soluble ingredients extracted from the roots of Polygonatum odoratum. The structures of all isolates were elucidated by NMR, MS and CD experiments, of which 1 (polygodoquinone A) was identified as a new anthraquinone derivative. Specifically, 1 represents an unusual structure composed of a naphthoquinone derivative linked to an anthraquinone via a C-C bond. 1-3 exhibited remarkable influenza A virus inhibitory activity with IC₅₀ values of 11.4, 11.0, and 2.3 μM, respectively, which were better than ribavirin as the positive control.

Geographic Distance and Habitat Type Influence Fungal Communities in the Arctic and Antarctic Sites

The Antarctic and Arctic regions are collectively referred to as the "Two Poles" of the earth and have extremely harsh climate conditions and fragile ecosystems. Until now, the biogeography of the fungal communities in the bipolar regions is not well known. In this study, we focused on the fungal communities in 110 samples collected from four habitat types (i.e., soil, vascular plant, freshwater, moss) in the Antarctic and Arctic sites using high-throughput sequencing. The data showed that the diversity and composition of fungal communities were both geographically patterned and habitat-patterned. ANOSIM tests revealed statistically significant differences among fungal communities in the eight sample types (R = 0.5035, p < 0.001) and those in the bipolar regions (R = 0.32859, p < 0.001). Only 396 OTUs (14.8%) were shared between the bipolar sites. Fungal communities in the four habitat types clustered together in the Arctic site but were separate from those of the Antarctic site, indicating that geographic distance was a more important determinant of fungal communities in the bipolar sites. These findings offer insights into the present-day biogeography of fungal communities in the bipolar sites.

Fusapyrone A, a γ-pyrone derived from a desert Fusarium sp

In this work, we isolated and characterized fusapyrone A (1), a new γ-pyrone derivative, along with six previously described compounds from the rice fermentation of Fusarium sp. CPCC 401218, a fungus collected from the desert. The structure of 1 was characterized using various spectroscopic analyses, such as MS, IR, 1D, and 2D NMR. The absolute configuration of 1 was determined through the use of ¹³C NMR chemical shifts, electronic circular dichroism (ECD) and optical rotation (OR) calculations. Compound 1 was found to have weak antiproliferative activity for Hela cells, with an IC₅₀ of 50.6 μM.[Formula: see text].

Saccharomycomorpha psychra n. g., n. sp., a Novel Member of Glissmonadida (Cercozoa) Isolated from Arctic and Antarctica

A novel genus and species within the order Glissmonadida (Cercozoa, Rhizaria), Saccharomycomorpha psychra n. g., n. sp., is described from lichen in the Ny-Ålesund region (High Arctic) and moss in the Fildes peninsula of King George Island (Maritime Antarctica). Cells were spherical and did not appear to present flagella in organic-rich Potato Dextrose Agar medium where they were able to feed osmotrophically. Molecular phylogenetic analyses based on 18S rRNA gene sequence demonstrated that Saccharomycomorpha psychra belong to "clade T" within the order Glissmonadida (Cercozoa, Rhizaria). All three investigated strains could grow at 4 °C and had an optimum growth temperature of 12 °C, 20 °C, and 20 °C, while a maximum growth temperature of 20 °C, 20 °C, and 25 °C, respectively. In conclusion, we established the phenotypic identity of "clade T," which until now was exclusively detected by environmental sequences, and erect a new family Saccharomycomorphidae for "clade T." Nomenclatural, morphological and ecological aspects of this novel species are discussed.

Roseomonas harenae sp. nov., from desert gravel soil

A Gram-stain-negative, aerobic, non-motile, pink-pigmented, coccus bacterium, designated CPCC 101081^T, was isolated from a gravel soil sample collected from Badain Jara desert, PR China. Growth of the isolate occurred at 10-37 °C and pH 5.0-8.0, with optimal growth at 28-32 °C and pH 7.0, respectively. The major cellular fatty acids were summed feature 8 (C_18:1ω7c/C _18:1ω6c), summed feature 3 (C _16:1ω6c/C_16:1ω7c) and C_18:12-OH. Q-10 was detected as the main respiratory quinone. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified phospholipid, an amino-containing lipid and an unidentified glycophospholipid were examined in the polar lipids extraction. The 16S rRNA gene sequence comparison of strain CPCC 101081^T with the available sequences in the GenBank database showed that the isolate was closely related to members of the genus Rosenomonas, with the highest similarity to Roseomonas rosea DSM 14916^T (97.4 %). In the phylogenetic trees based on 16S rRNA gene sequences and the core genomes, strain CPCC 101081^T was included within the clade of the genus Roseomonas, representing a species level, with the closest neighbor of R. rosea DSM 14916^T . The genomic DNA G+C content was 68.7 mol%. The average nucleotide identity and the digital DNA-DNA hybridization values between strain CPCC 101081^T and the related type strains of the genus Roseomonas were all far lower than the cut-off values for definition species. On the basis of above phenotypic and genotypic characteristics, strain CPCC 101081^T is proposed to represent a novel species of the genus Roseomonas with the name Roseomonas harenae sp. nov. strain CPCC 101081^T (=KCTC 62852^T=NBRC 113512^T) is the type strain of the species.

Ornithinimicrobium cerasi sp. nov., isolated from the fruit of Cerasus pseudocerasus and emended description of the genus Ornithinimicrobium

Strain CPCC 203383^T, isolated from the surface-sterilized fruit of Cerasus pseudocerasus (Lindl.) G. Don, was taxonomically characterized based on a polyphasic investigation. It had the highest 16S rRNA gene sequence similarities with Ornithinimicrobium pekingense DSM 21552 (97.2 %) and O. kibberense DSM 17687^T (97.2%). Phylogenetic analysis based on 16S rRNA gene sequences showed that the strain formed a distinct phyletic branch within the genus Ornithinimicrobium and the whole genome sequence data analyses supported that strain CPCC 203383^T was phylogenetically related to the Ornithinimicrobium species. The isolate shared a range of phenotypic patterns reported for members of the genus Ornithinimicrobium, but also had a range of cultural, physiological and biochemical characteristics that separated it from related Ornithinimicrobium species. The menaquinone was MK-8(H₄). The polar lipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylinositol (PI) and unidentified lipids (ULs). The major fatty acids (>5 %) were iso-C_15 : 0, anteiso-C_15 : 0, iso-C_16:0, 9-methyl C_16 : 0, iso-C_17 : 0 and anteiso-C_17 : 0. The cell wall peptidoglycan contains l-ornithine as diagnostic diamino acid and an interpeptide bridge consisting of _L-Orn←_L-Ala←Gly←_D-Asp. The combined genotypic and phenotypic data indicated that the isolate represents a novel species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium cerasi sp. nov. is proposed, with CPCC 203383^T(=NBRC 113522^T=KCTC 49200^T) as the type strain. The DNA G+C composition is 72.3 mol%. The availability of new data allows for an emended description of the genus Ornithinimicrobium.

Roseomonas vastitatis sp. nov. isolated from Badain Jaran desert in China

A Gram-stain-negative, non-motile, coccobacillus-shaped bacterium, designated CPCC 101021^T, was isolated from a sandy soil sample collected from Badain Jaran desert, China. Its 16S rRNA gene sequence was closely related to those of members of the genus Roseomonas, showing high similarities with Roseomonas hibiscisoli THG-N2.22^T (98.0 %), Roseomonas oryzae KCTC 42542^T (97.9 %), Roseomonas rhizosphaerae YW11^T (97.9 %) and Roseomonas suffusca S1^T (97.8 %). In the phylogenetic tree based on 16S rRNA gene sequences, strain CPCC 101021^T formed a distinct subclade with R. oryzae KCTC 42542^T within the genus Roseomonas. Growth of the isolate occurred at 15-37 °C and pH 6.0-8.5, with optimal growth at 30 °C and pH 7.0. The major cellular fatty acids were C_18 : 1ω7c, summed feature 8 (C_16 : 1ω7c/C_16 : 1ω6c), summed feature 3 (C_16 : 1ω6c/C_16 : 1ω7c) and C_16 : 0ω6c. Q-10 was detected as the main component in the respiratory quinone system, with Q-9 as a minor component. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, an unidentified phospholipid, an unidentified aminolipid and an unidentified glycolipid were found in the polar lipid profile. The genomic DNA G+C content was 68.7 mol%. The average nucleotide identity was 84.6 % when comparing the draft genome sequences of strain CPCC 101021^T with R. oryzae KCTC 42542^T. On the basis of genotypic, chemotaxonomic and phenotypic characteristics, strain CPCC 101021^T is proposed to represent a novel species of the genus Roseomonas with the name Roseomonas vastitatis sp. nov. Strain CPCC 101021^T (=J1A743^T=KCTC 62043^T) is the type strain of the species.

Desertihabitans aurantiacus gen. nov., sp. nov., a novel member of the family Propionibacteriaceae

The taxonomic position of an actinobacterium isolated from a desert soil sample collected from Badain Jaran Desert, designated as CPCC 204711^T, was established using a polyphasic approach. Cells of the isolate were Gram-staining-positive, aerobic, non-motile cocci. Good growth was observed at 28 °C (range 20-40 °C), pH 7.0 (range pH 6.0-8.0) and 0-1 % NaCl concentration (range 0-5 %, w/v). Galactose, arabinose and ribose were detected as the sugar compositions in the whole cell hydrolysates. The peptidoglycan type was A3gamma (ll-Dpm-Gly). MK-9(H4) was detected as the predominant menaquinone, and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, several unidentified glycolipids, and one unidentified amino-glycolipid were detected as the major polar lipids. The predominant fatty acid was anteiso-C15 : 0. The genomic DNA G+C content was 73.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CPCC 204711^T affiliated to the family Propionibacteriaceae, in which the strain formed a distinct phylogenetic lineage next to the genus Mariniluteicoccus, with the highest 16S rRNA gene sequence similarity of 96.0 % to Mariniluteicoccus endophyticus YIM 2617^T. Both phylogenetic analysis and phenotypic characteristics supported that strain CPCC 204711^T represents a novel species of a new genus in the family Propionibacteriaceae, for which the name Desertihabitans aurantiacus gen. nov., sp. nov. is proposed, with CPCC 204711^T (=KCTC 39977^T=DSM 105431^T) as the type strain.

Roseomonas globiformis sp. nov., an airborne bacteria isolated from an urban area of Beijing

A novel dark pink pigmented bacterium, designated strain CPCC 100847^T (deposited with strain code 0113-15), was isolated from the urban air of Beijing, China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CPCC 100847^T was related to members of the genus Roseomonas and had the highest 16S rRNA gene sequence similarity to Roseomonas aestuarii JC17^T (97.5 %). A low level of DNA-DNA relatedness (18.7 %) with its closest type strain R. aestuarii JC17^T (KCTC 22692^T) proved that strain CPCC 100847^T belonged to a unique genomic species. CPCC 100847^T had many common characteristics of the genus Roseomonas, but also had a range of cultural, physiological and biochemical characteristics that separated it from related Roseomonas species. Cells were Gram-negative, cocci- to oval-shaped, non-motile, non-endospore-forming and strictly aerobic. The respiratory ubiquinone was Q-10. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified aminolipid and an unidentified phospholipid. The major fatty acids (>5 %) were C18 : 1ω7c, anteiso-C15 : 0, C16 : 0, iso-C15 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The combined genotypic and phenotypic data indicated that the isolate represents a novel species of the genus Roseomonas. The name proposed for this species is Roseomonasglobiformis sp. nov., with CPCC 100847^T (=KCTC 52094^T) as the type strain. The DNA G+C composition is 65.2 mol%.

UGT73F17, a new glycosyltransferase from Glycyrrhiza uralensis, catalyzes the regiospecific glycosylation of pentacyclic triterpenoids

The regiospecific glycosylation of pentacyclic triterpenoids by UGT73F17, a new glycosyltransferase from Glycyrrhiza uralensis, is highlighted. UGT73F17 exhibited strict substrate specificity toward the carboxyl group at C-30/C-29 of pentacyclic triterpenoids, and showed high promiscuity to sugar donors. UGT73F17 represents the first identified triterpenoid 30/29-O-glycosyltransferase, and could be used as an effective biocatalyst to synthesize glycosyl ester saponins.

Diversity of Bacteria and the Characteristics of Actinobacteria Community Structure in Badain Jaran Desert and Tengger Desert of China

To assess the diversity of actinobacterial taxa in desert sands and obtain the novel microbial resources, 79 and 50 samples were collected from the Badain Jaran (BJD) and Tengger Deserts (TGD) of China, respectively. High-throughput sequencing (HTS) of environmental 16S rRNA genes within these samples was conducted on an Illumina Miseq platform, using universal bacterial primers targeting the V3–V4 hypervariable region. Based on the HTS analyses, cultivation-dependent (CULD) techniques were optimized to identify the cultivable Actinobacteria members. A total of 346,766 16S rRNA gene reads comprising 3,365 operational taxonomic units (OTUs) were obtained from the BJD sands using HTS, while 170,583 reads comprising 1,250 OTUs were detected in the TGD sands. Taxonomic classification indicated that Actinobacteria was the predominant phylum, comprising 35.0 and 29.4% of the communities in BJD and TGD sands, respectively. Among the Actinobacteria, members of the Geodermatophilaceae were considerably abundant in both deserts, indicating that they represent ubiquitous populations within the deserts. At the genus level, Arthrobacter spp. and Kocuria spp. were dominant, and corresponded to 21.2 and 5.3% of the actinobacterial communities in BJD and TGD deserts, respectively. A total of 786 and 376 actinobacterial strains were isolated and identified from BJD and TGD samples, respectively. The isolates comprised 73 genera of 30 families within the phylum Actinobacteria. In addition to the Geodermatophilaceae, Streptomyces spp. were a prominent component of the isolates, comprising 25% of the isolates from BJD and 17.5% of those from TGD. Comparison of the actinobacterial community structure in other ecosystems indicated that Geodermatophilaceae was the main actinobacterial group in desert sands, which is consistent with our results. Additionally, in these desert habits, Geodermatophilaceae and some other core groups may promote or inhabit the subsequent members' occurrence or prosper to shape the bacteria community structure. However, it should be noted that a number of other low-abundance bacteria appear to be specific to desert sands, which are worth further investigation. In antimicrobial activity assays, 10.36 % of the tested isolates showed antimicrobial activities in one or more screens. Importantly, 37 of the newly isolated strains reported here represent novel taxa that could be valuable resources for further research of novel secondary metabolites and their ecological significance in deserts.

Secoiridoid analogues from the fruits of Ligustrum lucidum and their inhibitory activities against influenza A virus

A phytochemical study focusing on the secoiridoid components in the fruits of Ligustrum lucidum was carried out, which finally led to the isolation of nine secoiridoid glycosides (1-9) together with two secoiridoids (10, 11). The structures of all compounds were established mainly by NMR and MS experiments as well as the necessary chemical evidence, of which 1, 2, 4 (ligulucisides A-C), 10 and 11 (liguluciridoids A and B) were identified as new secoiridoid analogues. An in vitro antiviral bioassay indicated that 1, 4, 6, and 10 displayed the inhibitory activities against influenza A virus with the IC₅₀ values of 16.5, 12.5, 13.1, and 18.5 μM, respectively, which were better than the positive control Ribavirin (IC₅₀ 22.6 μM). .

Ahmpatinin iBu, a new HIV-1 protease inhibitor, from Streptomyces sp. CPCC 202950

Ahmpatinin ⁱBu (1) and statinin ⁱBu (2), two new linear peptides, a novel pyrrolidine derivative, (−)-(S)-2-[3-(6-methylheptanamido)-2-oxopyrrolidin-1-yl] acetic acid (3), and three known pepstatin derivatives (4–6) along with their corresponding methanolysis artifacts (7–9) were isolated from Streptomyces sp. CPCC 202950. Their structures were elucidated on the basis of extensive spectroscopic data using Marfey's analysis, chiral-phase HPLC, and ECD and OR calculation to determine the absolute configurations. Compound 1 contains an unusual amino acid, 4-amino-3-hydroxy-5-(4-methoxyphenyl)pentanoic acid (Ahmppa), and 3 is the first natural product with a 2-(3-amino-2-oxopyrrolidin-1-yl)acetic acid system. Compounds 1, 2, and 4–9 are HIV-1 protease inhibitors. In particular, ahmpatinin ⁱBu (1) exhibits significant inhibitory activity against HIV-1 protease with an IC₅₀ value of 1.79 nM. A preliminary structure–activity relationship is discussed.

Ahmpatinin ⁱBu and statinin ⁱBu, two new linear peptides, were isolated from Streptomyces sp. CPCC 202950. Ahmpatinin ⁱBu exhibited significant inhibitory activity against HIV-1 protease with an IC₅₀ value of 1.79 nM.

Metabolites from the Plant Endophytic Fungus Aspergillus sp. CPCC 400735 and Their Anti-HIV Activities

Thirty-three metabolites including five phenalenone derivatives (1-5), seven cytochalasins (6-12), thirteen butenolides (13-25), and eight phenyl derivatives (26-33) were isolated from Aspergillus sp. CPCC 400735 cultured on rice. The structures of all compounds were elucidated by NMR, MS, and CD experiments, of which 1-5 (asperphenalenones A-E), 6 (aspochalasin R), and 13 (aspulvinone R) were identified as new compounds. Specifically, asperphenalenones A-E (1-5) represent an unusual structure composed of a linear diterpene derivative linked to a phenalenone derivative via a C-C bond. Compounds 1, 4, 10, and 26 exhibited anti-HIV activity with IC₅₀ values of 4.5, 2.4, 9.2, and 6.6 μM, respectively (lamivudine 0.1 μM; efavirenz, 0.4 × 10^-3 μM).

Ornithinimicrobium flavum sp. nov., isolated from the leaf of Paris polyphylla

A Gram-positive bacterium originating from the surface-sterilized leaf of Paris polyphylla var. yunnanensis (Franch.) was characterized by using a polyphasic approach. The isolate formed yellow, smooth, circular colonies on nutrient agar with 0.2 % starch (NSA). Cells were non-motile, non-sporulating, irregular rods or cocci. Strain CPCC 203535^T had the highest 16S rRNA gene sequence similarity to the type strain of Ornithinimicrobium kibberense (96.9 %) and formed the deepest branch in the genus Ornithinimicrobium in the neighbour-joining (NJ) phylogenetic tree based on 16S rRNA gene sequences. The major menaquinones of strain CPCC 203535^T were MK-8(H4), MK-8(H2) and MK-8. The peptidoglycan contained ornithine as the diagnostic diamino acid. The polar lipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylinositol (PI) and unknown lipid (UL). The major fatty acids iso-C14 : 0, iso-C15 : 0, iso-C16 : 0 and anteiso-C15 : 0 were consistent with the fatty acid patterns reported for members of the genus Ornithinimicrobium. The DNA G+C composition is 71.4 mol%. The results of physiological and biochemical tests allowed phenotypic differentiation of strain CPCC 203535^T from its closest phylogenetic species in the genus Ornithinimicrobium. Strain CPCC 203535^T represents a novel species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium flavum sp. nov. is proposed, with CPCC 203535^T (=NBRC 109452 ^T=KCTC 29164^T) as the type strain.

Allobranchiibius huperziae gen. nov., sp. nov., a member of Dermacoccaceae isolated from the root of a medicinal plant Huperzia serrata (Thunb.)

A Gram-stain-positive, non-spore-forming actinobacterial strain, designated CPCC 204077^T, was isolated from the surface-sterilized root of a medicinal plant Huperzia serrata (Thunb.) collected from Sichuan Province, south-west China. The peptidoglycan type of strain CPCC 204077^T was detected as A4α with an l-Lys-l-Ser-d-Asp interpeptide bridge. Galactose, glucose, rhamnose and ribose were the sugar compositions in the whole-cell hydrolysates. MK-8(H4) was the only menaquinone. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, one unidentified phospholipid and one unidentified glycolipid. The major fatty acid was iso-C16 : 0. The genomic DNA G+C content was 71.0 mol%. The phylogenetic tree based on 16S rRNA gene sequences showed that strain CPCC 204077^T stood for a distinct lineage within the family Dermacoccaceaealongside the genera Branchiibius, Demetria and Barrientosiimonas, with the highest 16S rRNA gene sequence similarities to Branchiibius hedensis Mer 29717^T (95.0 %), Calidifontibacter indicus PC IW02^T (95.0 %), Barrientosiimonas humi 39^T (94.9 %) and Demetria terragena HKI 0089^T (94.7 %), and less than 94.7 % sequence similarities to all other species. Signature nucleotides in the 16S rRNA sequence showed that the strain contained the Dermacoccaceaefamily-specific 16S rRNA signature nucleotides and a genus-specific diagnostic nucleotide signature pattern. Combining the genotypic and phenotypic analyses, we propose that strain CPCC 204077^T represents a novel species of a new genus in the family Dermacoccaceae with the name Allobranchiibius huperziae gen. nov., sp. nov. Strain CPCC 204077^T (=NBRC 110719^T=DSM 29531^T) is the type strain of the type species.

[A new benzamide derivative from rice fermentation of Streptomyces sp. CPCC 202950]

Eight compounds were isolated from the rice fermentation of Streptomyces sp. CPCC 202950 by a combination of various chromatographic techniques including column chromatography over silica, Sephadex LH-20, flash C₁₈, and reversed-phase HPLC. Their structures were identified as 3-[(3'-amino-3'-oxoprop-1'-en-2'-yl)oxy]benzamide (1), m-hydroxybenzamide (2), leptosphaepin (3), 5-methyluracil (4), feruloylamide (5), p-hydroxyphenylacetoamide (6), vanillamide (7), cyclo (L-val-L-ala) (8). Among them, 1 was a new benzamide analogue, and 2 was a new natural product. In the preliminary assays, none of the compounds 1-8 exhibited obvious inhibition of HIV-1 protease activity, and toxic with the Hela, HepG2, and U2OS cells. (IC₅₀ > 10 μmol•L⁻¹).

[Sedimentary Characteristics and Sources of Organic Matter in Sediments of Dianchi Lake]

Sediment columns in the southeast and east of Dianchi Lake were taken as the object of the study to determine ages by ²¹⁰ Pb dating method.The contents and sediment fluxes of total organic carbon (TOC) and n-alkanes of the sediments were investigated,and organic sources were tracked according to the relevant indexes of n-alkanes.The results indicated that TOC contents and sediment fluxes of two sampling sediments both presented an increasing trend on the whole;Sediment fluxes of n-alkanes varied as three stages:increasing period,decreasing period and re-increasing period.When the sediment fluxes of n-alkanes and TOC both went up,it showed that they had the same sources:sediments in the lake and carried by the rivers;From 1980s to the end of 20^th century,sediment fluxes of n-alkanes were going down while those of TOC were going up.This result means there was a big difference in the sources of n-alkanes and TOC.The bacteria and algae in the lake made a great contribution to n-alkanes while TOC was mainly influenced by sediments in the lake and carried by the rivers.n-alkanes of the two sampling sites both ranged from C₁₂ to C₃₅.Based on the basic features and relevant indexes of n-alkanes,we proposed that emergent plants made big contributions to the sources of organic matter in the sediments of Dianchi Lake,simultaneously,bacteria and algae had significant contributions to the sources of organic matter in shallow depth of Dianchi Lake.

Polyoxypregnane Glycosides from the Roots of Marsdenia tenacissima and Their Anti-HIV Activities

A continuous phytochemical study on the roots of Marsdenia tenacissima led to the isolation and identification of 13 new polyoxypregnane glycosides named marstenacissides B10-B17 (1, 2, 4, 7, 8, 11, 12, and 14) and marstenacissides A8-A12 (3, 9, 10, 13, and 15) in addition to two known polyoxypregnane glycosides marsdenosides M and L (5 and 6). Their structures were established by spectroscopic techniques and by comparison with the reported data in the literature. Moreover, the anti-HIV activities of these isolates and the previous isolated marstenacissides A1-A7 and B1-B9 were assessed, some of which exhibited slight or negligible effects against HIV-1.

PRECLINICAL PHARMACOKINETIC ANALYSIS OF (E)-METHYL-4-ARYL-4-OXABUT-2-ENOATE, A NOVEL SER/THR PROTEIN KINASE B INIBITOR, IN RATS

(E)-Methyl-4-aryl-4-oxabut-2-enoate, designated YH-8, is a novel Serflhr protein kinase B (PknB) inhibitor, which is designed for the treatment of tuberculosis. The aim of this study was to investigate the pharmacokinetics, bioavailability, tissue distribution and excretion characteristics of YH-8 in rats and study its plasma protein binding in vitro. The pharmacokinetic properties were examined after intravenously injected YH-8 at 10 and 20 mg/kg and oral administrated YH-8 at 50, 100 and 200 mg/kg to rats. The concentrations of YH-8 in plasma were determined with LC-MS/MS, with a liquid-liquid extraction. The tissue distribution and urinary, fecal and -biliary excretion patterns of YH-8 were investigated following a single oral dosing of 100 mg/kg. The plasma protein binding rates of YH-8 were determined using ultra-filtration method. After intra- venous and oral administration, YH-8 showed dose-independent pharmacokinetic characteristics, with T(1/2) of approximately 5.5 h and 7.1 h, respectively. The oral absolute bioavailability of YH-8 was relatively low (about 12%). YH-8 was widely distributed in various tissues and showed substantial deposition in intestine, stomach, liver, lung and kidney. The drug was mainly eliminated via fecal excretion and its binding rate with plasma protein was concentration-dependent. In conclusion, this study as first provided the full pharmacokinetic characteristics of YH-8, which would be helpful for its further development and clinical application.

Paenibacillus eucommiae sp. nov., isolated from a traditional Chinese medicinal herbal plant, Eucommia ulmoides Oliver

The taxonomic status of a novel bacterium, designated strain CPCC 100226T, isolated from a traditional Chinese medicinal herbal plant, Eucommia ulmoides Oliver, was characterized by using a polyphasic approach. The aerobic isolate formed pale white colonies on tryptic soy agar. Cells were Gram-stain-positive, rod-shaped, motile and endospore-forming. Chemotaxonomic investigations revealed the presence of meso-diaminopimelic acid as the diagnostic diamino acid, MK-7 as the predominant menaquinone, anteiso-C15 : 0, iso-C15 : 0, iso-C16 : 0 and C16 : 0 as the major fatty acids, and the strain had a phospholipid pattern of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and unidentified aminophospholipids. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the isolate was closely related to Paenibacillus aestuarii DSM 23861T with 95.1 % similarity. The G+C content of the genomic DNA was 47.9 mol%. On the basis of the genotypic and phenotypic data, the isolate is considered to represent a novel species of the genus Paenibacillus. The name proposed for this taxon is Paenibacillus eucommiae sp. nov. with CPCC 100226T (=DSM 26048T=KCTC 33054T) as the type strain.

[Distribution Characteristics of n-alkanes in Sediment Core and Implication of Environment in Different Lakes of Dianchi]

In order to study the composition and environment significance of the organic matter in Lake Dianchi, samples from two sediment cores from the northern and southern parts of the lake were collected in July, 2014. Meanwhile, the vertical distributions of total organiccarbon (TOC), total nitrogen (TN), n-alkanes fractions were investigated. The results showed that ① the concentrations of TOC and TN had been clearly increasing since the 1970s, which implied that the primary productivity of Lake Dianchi was continuously enhanced; ② The values of the parameter n-C₂₇/n-C₃₁, P_aqand CPI indicated the alternation between herbs and woody plants from the bottom up in Lake Dianchi sediments. Besides, the high carbon number of organic matter in sediments mainly originated from endogenous submerged floating and large plants; ③ The index of C/N and distribution characteristics of n-alkanes suggested differences in the various sources of organic matter in different lakes. In detail, organic matter came from terrigenous organic matter of anthropogenic sources and endogenous bacteria in the sediments of northern Dianchi, while organic matter was derived from endogenous aquatic and terrestrial higher plants mixed source in the sediments of southern Dianchi. Finally, it is worthwhile to emphasize further research on organic matter in different lakes of Lake Dianchi.

Structure-based optimization of salt-bridge network across the complex interface of PTPN4 PDZ domain with its peptide ligands in neuroglioma

The PTP non-receptor type 4 (PTPN4) is an important regulator protein in learning, spatial memory and cerebellar synaptic plasticity; targeting the PDZ domain of PTPN4 has become as attractive therapeutic strategy for human neuroglioma. Here, we systematically examined the complex crystal structures of PTPN4 PDZ domain with its known peptide ligands; a number of charged amino acid residues were identified in these ligands and in the peptide-binding pocket of PDZ domain, which can constitute a complicated salt-bridge network across the complex interface. Molecular dynamics (MD) simulations, binding free energy calculations and continuum model analysis revealed that the electrostatic effect plays a predominant role in domain-peptide binding, while other noncovalent interactions such as hydrogen bonds and hydrophobic forces are also responsible for the binding. The computational findings were then used to guide structure-based optimization of the interfacial salt-bridge network. Consequently, five peptides were rationally designed using the high-affinity binder Cyto8-RETEV (RETEV^-COOH) as template, including four single-point mutants (i.e. Cyto8-mtxe₀: RETEE^-COOH, Cyto8-mtxd_-1: RETDV^-COOH, Cyto8-mtxd_-3: RDTEV^-COOH and Cyto8-mtxk_-4: KETEV^-COOH) and one double-point mutant (i.e. Cyto8-mtxd_-1k_-4: KETDV^-COOH). Binding assays confirmed that three (Cyto8-mtxd_-1, Cyto8-mtxk_-4 and Cyto8-mtxd_-1k_-4) out of the five designed peptides exhibit moderately or considerably increased affinity as compared to the native peptide Cyto8-RETEV.

Herbihabitans rhizosphaerae gen. nov., sp. nov., a member of the family Pseudonocardiaceae isolated from rhizosphere soil of the herb Limonium sinense (Girard)

The taxonomic position of an actinobacterium, designated CPCC 204279T, which was isolated from a rhizosphere soil sample of the herb Limonium sinense collected from Xinjiang Province, China, was established using a polyphasic approach. Whole-cell hydrolysates of strain CPCC 204279T contained galactose and arabinose as diagnostic sugars and meso-diaminopimelic acid as the diamino acid. The muramic acid residues in the peptidoglycan were N-acetylated. The predominant menaquinone was MK-9(H4). The phospholipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides. The major fatty acids were iso-C16 : 0, iso-C16 : 0 2-OH, C16 : 1ω9c, iso-C16 : 1 and C16 : 0. The genomic DNA G+C content was 73.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CPCC 204279T should be placed in the family Pseudonocardiaceae, in which the strain formed a distinct lineage next to the genus Actinophytocola. Signature nucleotides in the 16S rRNA gene sequence showed that the strain contained the Pseudonocardiaceae family-specific 16S rRNA signature nucleotides and a genus-specific diagnostic nucleotide signature pattern. The combination of phylogenetic analysis and phenotypic characteristics supported the conclusion that strain CPCC 204279T represents a novel species of a new genus in the family Pseudonocardiaceae, for which the name Herbihabitans rhizosphaerae gen. nov., sp. nov. is proposed. Strain CPCC 204279T (=NBRC 111774T=DSM 101727T) is the type strain of the type species.

Jatrophihabitans huperziae sp. nov., an endophytic actinobacterium isolated from surface-sterilized tissue of the medicinal plant Huperzia serrata (Thunb.)

A novel endophytic actinobacterium, designated strain CPCC 204076T, was isolated from surface-sterilized tissue of the medicinal plant Huperzia serrata (Thunb.) collected from Sichuan Province, south-west China. The taxonomic position of the isolate was investigated by a polyphasic approach. The strainwas aerobic, Gram-stain-positive, non-motile, non-spore-forming and rod-shaped. Growth was observed at 10-37 °C, at pH 5.0-10.0 and with 0-3.0 % (w/v) NaCl. The polar lipid fraction consisted of diphosphatidylglycerol, a phospholipid, an aminolipid, a glycolipid, an aminophospholipid and phosphatidylinositol. The cell wall contained meso-diaminopimelic acid as the diagnostic diamino acid and the peptidoglycan was of type A4γ. The menaquinone system consisted of MK-9(H4) and MK-8(H4). The major cellular fatty acids (>10 %) were iso-C16 : 0 and anteiso-C17 : 0. The genomic DNA G+C content of strain CPCC 204076T was found to be 71.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that CPCC 204076T belongs to the genus Jatrophihabitans with highest sequence similarity to Jatrophihabitans endophyticus DSM 45627T (96.5 %), Jatrophihabitans soli DSM 45908T (96.5 %) and Jatrophihabitans fulvus JCM 30448T (96.1 %), and much lower similarities (<95.0 %) to other available 16S rRNA gene sequences from validly described pure cultures. However, DNA-DNA hybridyzation values between strain CPCC 204076T and the three recognized Jatrophihabitans species were 31±3.1 % (J. endophyticus DSM 45627T), 33±2.9 % (J. soli DSM 45908T) and 37±1.7 % (J. fulvus JCM 30448T), which were all far below the recommended cut-off value of 70 %. The phenotypic and genomic characteristics distinctly indicated that strain CPCC 204076T represents a novel species of the genus Jatrophihabitans, for which the name Jatrophihabitans huperziae sp. nov. is proposed. The type strain is CPCC 204076T (I13A-01604) (=DSM 46866T=NBRC 110718T).