Inhibition of Hmbox1 Promotes Cardiomyocyte Survival and Glucose Metabolism Through Gck Activation in Ischemia/Reperfusion Injury.

BACKGROUND: Exercise-induced physiological cardiac growth regulators may protect the heart from ischemia/reperfusion (I/R) injury. Homeobox-containing 1 (Hmbox1), a homeobox family member, has been identified as a putative transcriptional repressor and is downregulated in the exercised heart. However, its roles in exercise-induced physiological cardiac growth and its potential protective effects against cardiac I/R injury remain largely unexplored. METHODS: We studied the function of Hmbox1 in exercise-induced physiological cardiac growth in mice after 4 weeks of swimming exercise. Hmbox1 expression was then evaluated in human heart samples from deceased patients with myocardial infarction and in the animal cardiac I/R injury model. Its role in cardiac I/R injury was examined in mice with adeno-associated virus 9 (AAV9) vector-mediated Hmbox1 knockdown and in those with cardiac myocyte-specific Hmbox1 ablation. We performed RNA sequencing, promoter prediction, and binding assays and identified glucokinase (Gck) as a downstream effector of Hmbox1. The effects of Hmbox1 together with Gck were examined in cardiomyocytes to evaluate their cell size, proliferation, apoptosis, mitochondrial respiration, and glycolysis. The function of upstream regulator of Hmbox1, ETS1, was investigated through ETS1 overexpression in cardiac I/R mice in vivo. RESULTS: We demonstrated that Hmbox1 downregulation was required for exercise-induced physiological cardiac growth. Inhibition of Hmbox1 increased cardiomyocyte size in isolated neonatal rat cardiomyocytes and human embryonic stem cell-derived cardiomyocytes but did not affect cardiomyocyte proliferation. Under pathological conditions, Hmbox1 was upregulated in both human and animal postinfarct cardiac tissues. Furthermore, both cardiac myocyte-specific Hmbox1 knockout and AAV9-mediated Hmbox1 knockdown protected against cardiac I/R injury and heart failure. Therapeutic effects were observed when sh-Hmbox1 AAV9 was administered after I/R injury. Inhibition of Hmbox1 activated the Akt/mTOR/P70S6K pathway and transcriptionally upregulated Gck, leading to reduced apoptosis and improved mitochondrial respiration and glycolysis in cardiomyocytes. ETS1 functioned as an upstream negative regulator of Hmbox1 transcription, and its overexpression was protective against cardiac I/R injury. CONCLUSIONS: Our studies unravel a new role for the transcriptional repressor Hmbox1 in exercise-induced physiological cardiac growth. They also highlight the therapeutic potential of targeting Hmbox1 to improve myocardial survival and glucose metabolism after I/R injury.

Actinoplanes sandaracinus sp. nov., a novel ligninase- producing and cellulose-degrading actinobacterium isolated from soil.

A novel ligninase-producing and cellulose-degrading actinobacterium, designated strain NEAU-A12T, was isolated from a soil sample collected from Aohan banner, Chifeng City, Inner Mongolia Autonomous Region, PR China. A polyphasic taxonomic study was used to establish the status of strain NEAU-A12T. 16S rRNA gene sequence analysis revealed that strain NEAU-A12T belonged to the genus Actinoplanes and showed the highest similarity (98.3 %) to Actinoplanes palleronii DSM 43940T, while showing less than 98.3 % similarity to other members of the genus Actinoplanes. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and glycosylphosphatidylinositol. The diagnostic sugars in cell hydrolysates were determined to be arabinose, glucose and xylose. The cell wall contained meso-diaminopimelic acid as the diagnostic diamino acid. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H2). The major fatty acids were C15 : 0, C16 : 0, C16 : 1 ω7c and C17 : 0. Meanwhile, genomic analysis revealed a genome size of 10 192 524 bp and a DNA G+C content of 70.6 mol%, and indicated that strain NEAU-A12T had the potential to degrade lignin and cellulose, as well as produce bioactive compounds. In addition, the average nucleotide identity values between strain NEAU-A12T and its reference strains A. palleronii DSM 43940T, Actinoplanes regularis DSM 43151T, Actinoplanes philippinensis DSM 43019T, Actinoplanes xinjiangensis DSM 45184T and Actinoplanes italicus DSM 43146T were 80.3, 80.3, 84.1, 84.3 and 84.0 %, respectively. The levels of digital DNA-DNA hybridization between them were found to be 23.6 % (21.3-26.1 %), 23.8 % (21.5-26.3 %), 28.3 % (25.9-30.8 %), 28.6 % (26.0-30.9 %) and 28.4 % (26.2-31.1 %), respectively. Based on phenotypic, chemotaxonomic and genotypic data, strain NEAU-A12T is considered to represent a novel species of the genus Actinoplanes, for which the name Actinoplanes sandaracinus sp. nov. is proposed, with NEAU-A12T (=CCTCC AA 2020039T=DSM 112043T) as the type strain.

Nitrate Reduction by NiFe-LDH/CeO2: Understanding the Synergistic Effect between Dual-Metal Sites and Dual Adsorption.

Electrocatalytic nitrate reduction reaction (EC-NITRR) shows a significant advantage for green reuse of the nitrate (NO3-) pollutant. However, the slow diffusion reaction limits the reaction rate in practical EC-NITRR, causing an unsatisfactory ammonia (NH3) yield. In this work, a multifunctional NiFe-LDH/CeO2 with the dual adsorption effect (physisorption and chemisorption) and dual-metal sites (Ce3+ and Fe2+) was fabricated by the electrodeposition method. NiFe-LDH/CeO2 performed an expected ability of enrichment for NO3- through the pseudo-first-order and pseudo-second-order kinetic models, and the polymetallic structure provided abundant sites for effective reaction of NO3-. At-0.6 V vs RHE, the ammonia (NH3) yield of NiFe-LDH/CeO2 reached 335.3 µg h-1 cm-2 and the selectivity of NH3 was 24.2 times that of NO2-. The nitrogen source of NH3 was confirmed by 15NO3- isotopic labeling. Therefore, this work achieved the recycling of the NO3- pollutant by synergy of enrichment and catalysis, providing an alternative approach for the recovery of NO3- from wastewater.

Changes in Concentrations of Polyfluoroalkyl Substances in Human Milk Over Lactation Time and Effects of Maternal Exposure via Analysis of Matched Samples.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are potentially related to many adverse health outcomes and could be transferred from maternal blood to human milk, which is an important exposure source for infants during a long-term period. In this study, the maternal blood of 76 women after delivery and their matched human milk samples obtained at 0.5, 1, and 3 months were analyzed by solid-phase extraction method with metal-organic framework/polymer hybrid nanofibers as the sorbents and ultrahigh-performance liquid chromatography-negative electrospray ionization mass spectrometric for quantitative analysis of 31 PFAS. The perfluorooctanoic acid, perfluorooctane sulfonate, and N-methyl perfluorooctane sulfonamido acetic acid (N-MeFOSAA) contributed to more than approximately 50% of the total PFAS concentrations in blood and human milk, while N-MeFOSAA (median: 0.274 ng/mL) was the highest PFAS in human milk at 3 months. The transfer efficiencies for PFAS from maternal blood to human milk at 0.5 months were generally lower, with medians ranging from 0.20% to 16.9%. The number of PFAS species detected in human milk increased as the lactation time went on from 0.5 to 3 months, and the concentrations of 10 PFAS displayed an increasing trend as the prolongation of lactation time (p < 0.05).

Association of Di(2-ethylhexyl) Terephthalate and Its Metabolites with Nonalcoholic Fatty Liver Disease: An Epidemiology and Toxicology Study.

As an alternative plasticizer to conventional phthalates, di(2-ethylhexyl) terephthalate (DEHTP) has attracted considerable concerns, given its widespread detection in the environment and humans. However, the potential toxicity, especially liver toxicity, posed by DEHTP remains unclear. In this study, based on the 2017-2018 National Health and Nutrition Examination Survey, two metabolites of DEHTP, i.e., mono(2-ethyl-5-hydroxyhexyl) terephthalate (MEHHTP) and mono(2-ethyl-5-carboxypentyl) terephthalate (MECPTP), were found to be present in the urine samples of nearly all representative U.S. adults. Moreover, a positive linear correlation was observed between the concentrations of the two metabolites and the risk of nonalcoholic fatty liver disease (NAFLD) in the population. Results of weighted quantile sum and Bayesian kernel machine regression indicated that MEHHTP contributed a greater weight to the risk of NAFLD in comparison with 12 conventional phthalate metabolites. In vitro experiments with hepatocyte HepG2 revealed that MEHHTP exposure could increase lipogenic gene programs, thereby promoting a dose-dependent hepatic lipid accumulation. Activation of liver X receptor α may be an important regulator of MEHHTP-induced hepatic lipid disorders. These findings provide new insights into the liver lipid metabolism toxicity potential of DEHTP exposure in the population.

Exploration of porous imine-based covalent organic framework for solid-phase extraction of five trace sulfonamides in food samples.

In this article, a highly crystalline porous imine-based covalent organic framework was synthesized at room temperature and used as solid-phase extraction (SPE) adsorbent for the purification and enrichment of trace sulfonamides (SAs) from food samples. The structure of the obtained material was characterized and studied in detail. The extraction process was optimized and the final elution was determined by the ultra-high-performance liquid chromatography-quadrupole time of flight mass spectrometry method. Low limits of detection (0.02-0.19 µg/kg) were obtained under optimal conditions, with the recoveries ranging from 70.5% to 105.3% when spiked at different levels. The adsorption process of the material for SAs was fitted by the Langmuir and Freundlich adsorption isotherm model, and the extraction capacity for Nitrofuran metabolites from food samples was also investigated for comparison. The results demonstrated that the framework was a good candidate SPE adsorbent that can be used for the enrichment of drug residues in complex matrix, and the work may provide a systematic study method for the development of porous adsorbents.

Catalytic oxidation of toluene by manganese oxides: Effect of K+ doping on oxygen vacancy.

Alkali metal potassium was beneficial to the electronic regulation and structural stability of transition metal oxides. Herein, K ions were introduced into manganese oxides by different methods to improve the degradation efficiency of toluene. The results of activity experiments indicated that KMnO4-HT (HT: Hydrothermal method) exhibited outstanding low-temperature catalytic activity, and 90% conversion of toluene can be achieved at 243°C, which was 41°C and 43°C lower than that of KNO3-HT and Mn-HT, respectively. The largest specific surface area was observed on KMnO4-HT, facilitating the adsorption of toluene. The formation of cryptomelane structure over KMnO4-HT could contribute to higher content of Mn3+ and lattice oxygen (Olatt), excellent low-temperature reducibility, and high oxygen mobility, which could increase the catalytic performance. Furthermore, two distinct degradation pathways were inferred. Pathway Ⅰ (KMnO4-HT): toluene → benzyl → benzoic acid → carbonate → CO2 and H2O; Pathway ⅠⅠ (Mn-HT): toluene → benzyl alcohol → benzoic acid → phenol → maleic anhydride → CO2 and H2O. Fewer intermediates were detected on KMnO4-HT, indicating its stronger oxidation capacity of toluene, which was originated from the doping of K+ and the interaction between KOMn. More intermediates were observed on Mn-HT, which can be attributed to the weaker oxidation ability of pure Mn. The results indicated that the doping of K+ can improve the catalytic oxidation capacity of toluene, resulting in promoted degradation of intermediates during the oxidation of toluene.

Synthesis of Au Nanoclusters by Reduction of Bovine Serum Albumin: The Role of Sodium Hydroxide.

Using bovine serum albumin (BSA) as both a reductant and ligand had been developed as one of the most used approaches for synthesis of fluorescent Au nanoclusters (NCs), in which first HAuCl4 and BSA were mixed together and then NaOH was added to the mixture after a certain time to obtain the Au NCs. In this work, the role of sodium hydroxide in the formation and emission properties of the Au NCs was investigated systematically. It was revealed, for the first time, that activity of the gold precursor and, thus, emission properties of the resulting Au NCs are dependent upon the addition time of sodium hydroxide. Meanwhile, the reducing ability of BSA is dependent upon the concentration of sodium hydroxide added to the reaction solution. By optimization of the addition time and concentration of sodium hydroxide used, Au NCs with improved emission properties were successfully synthesized under relatively low BSA concentrations, which showed improved performance toward the sensing of Cu2+ ions.

Strengthening the Stability of the Reconstructed NiOOH Phase for 5-Hydroxymethylfurfural Oxidation.

Electrochemical oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) is a promising approach to produce high-value chemicals such as 2,5-furandicarboxylic acid (FDCA). However, the undesirable stability of catalysts commonly limits its potential application value. In this work, NiOOH derived from Ni(OH)2 was determined as the main catalytic site for HMF oxidation, but the collapse of Ni(OH)2 caused severe instability during the electrocatalytic process because of the crystal structure mismatch between NiOOH and Ni(OH)2. The implantation of Ce in Ni(OH)2 (Ce-Ni(OH)2) was successfully realized to address the stability issue of bare Ni(OH)2, since the larger ion radius of Ce could increase the Ni-O bond length and d-spacing. As a result, the activity of 14%Ce-Ni(OH)2 has not obviously decayed after the 50 cyclic voltammetry (CV)-cycle test. HMF conversion is close to 100%, and the Faraday efficiency (FE) reaches 86.6% at the potential of 0.45 V vs Ag/AgCl. This study provides a new strategy to design stable catalysts for the conversion of biomass derivatives.

Per- and Polyfluoroalkyl Substances in Personal Hygiene Products: The Implications for Human Exposure and Emission to the Environment.

Per- and polyfluoroalkyl substances (PFAS) have been related to reproductive toxicity in humans, but their occurrence in some specific personal hygiene products, i.e., sanitary pads, panty liners, tampons, paper diapers, menstrual cups, and bactericidal liquids, has not been extensively studied. This work investigated 31 representative PFAS in six categories of such personal hygiene products (n = 91). Perfluorinated carboxylic acids were the primary PFAS found in the samples, accounting for over 85% of the total concentrations of PFAS. Paper diapers contained the highest sum of PFAS concentrations (64.6 ng/g) followed by sanitary pads (52.3 ng/g) and menstrual cups (21.1 ng/g). The estimated exposure doses of perfluorooctanoic acid through dermal absorption from the use of menstrual cups and paper diapers for infants (adults) were 0.77 and 2.1 (1.2) ng/kg-bw/day, which contributed more than normal dust ingestion. The estimated emission of paper diapers and sanitary pads into the environment was 2.58 and 322 kg/year with an assumed leaching rate of 100%. The potential exposure of PFAS through the use of personal hygiene products observed in this work suggests a previously unreported exposure pathway of these chemicals to humans.

miR-486 attenuates cardiac ischemia/reperfusion injury and mediates the beneficial effect of exercise for myocardial protection.

Exercise and its regulated molecules have myocardial protective effects against cardiac ischemia/reperfusion (I/R) injury. The muscle-enriched miR-486 was previously identified to be upregulated in the exercised heart, which prompted us to investigate the functional roles of miR-486 in cardiac I/R injury and to further explore its potential in contributing to exercise-induced protection against I/R injury. Our data showed that miR-486 was significantly downregulated in the heart upon cardiac I/R injury. Both preventive and therapeutic interventions of adeno-associated virus 9 (AAV9)-mediated miR-486 overexpression could reduce cardiac I/R injury. Using AAV9 expressing miR-486 with a cTnT promoter, we further demonstrated that cardiac muscle cell-targeted miR-486 overexpression was also sufficient to protect against cardiac I/R injury. Consistently, miR-486 was downregulated in oxygen-glucose deprivation/reperfusion (OGDR)-stressed cardiomyocytes, while upregulating miR-486 inhibited cardiomyocyte apoptosis through PTEN and FoxO1 inhibition and AKT/mTOR activation. Finally, we observed that miR-486 was necessary for exercise-induced protection against cardiac I/R injury. In conclusion, miR-486 is protective against cardiac I/R injury and myocardial apoptosis through targeting of PTEN and FoxO1 and activation of the AKT/mTOR pathway, and mediates the beneficial effect of exercise for myocardial protection. Increasing miR-486 might be a promising therapeutic strategy for myocardial protection.

Analysis of the typing of adenovirus and its clinical characteristics in children with acute respiratory tract infection.

BACKGROUND: The purpose of this study was to investigate the typing of adenovirus (AdV) infection in children hospitalized with acute respiratory tract infection (ARTI) and its clinical characteristics. METHODS: Samples from 7832 hospitalized children with ARTIs from January 2021 to June 2022 were tested by multiplex PCR for AdV. AdV hex neighborhood genes were amplified and sequenced for typing by nested PCR. RESULTS: Three hundred twenty-eight cases were positive for AdV with rate of 4.48% (328/7832). No statistical difference in the rate of AdV detection was observed in different ages (P > 0.05). Among the 328 cases, 305 cases underwent amplification and sequence determination of AdV five-neighborhood, six-neighborhood and fibronectin genes. Only 237 cases were sequenced successfully for all 3 genetic fragments. The typing results of 231 cases with 3 genes were consistent, with 49.78% (115/231) of type 3, 41.56% (96/231) of type 7 and 8.66% (20/231) of other types identified. The main clinical symptoms in 231 children hospitalized with ARTI who were AdV positive were cough, sputum not easily coughable, Wheezing or shortness of breath and fever. Clinical diagnoses of 231 cases included: acute bronchitis 3.03% (7/231), capillary bronchitis 16.45% (38/231), pneumonia (mild/severe) 76.62% (177/231) (68.40% (158/231) in mild and 8.23% (19/231) in severe cases), bronchial asthma combined with pulmonary infection 3.46% (8/231). Higher percentage of shortness of breath, multilobar infiltration, and pleural effusion were found in type 7. Calcitoninogen in type 7 were significantly higher than those of type 3 and other types, and the white blood cell count was lower than those of type 3 and other types, and the difference was statistically significant (P < 0.05). CONCLUSION: AdV type 3 and 7 were frequently found in hospitalized children with acute lower respiratory tract involvement. AdV type 7 seems to be associated with more severe outcome.

Nocardia rosealba sp. nov., a novel ligninase-producing Actinobacterium isolated from soil.

A novel ligninase-producing actinomycete, designated strain NEAU-G4T, was isolated from a soil sample and subjected to a polyphasic taxonomic study to establish its status. According to 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Nocardia, with the highest sequence similarity to Nocardia ignorata DSM 44496T (99.2 %). The whole-cell sugars contained galactose and arabinose. The amino acid of the cell wall was determined to be meso-diaminopimelic acid. The major fatty acids (>10 %) were C16 : 0, C18 : 1 ω9c, C18 : 0 and C16 : 1 ω7c. The predominant menaquinone was identified as MK-8(H6, ω-cycl). The major polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. Strain NEAU-G4T had a draft genome size of 6 405 167 bp, annotated with 5815 protein-coding genes. The DNA G+C content was 67.6 mol%. Phylogenetic analysis using the 16S rRNA gene and whole-genome sequences showed that strain NEAU-G4T formed a stable phyletic line with N. ignorata DSM 44496T. The digital DNA-DNA hybridization and average nucleotide identity values between them were 63.7 % (60.8-66.5 %) and 95.5 %, respectively. Moreover, genomic analysis indicated that strain NEAU-G4T had the potential to degrade lignin and produce bioactive compounds. On the basis of genotypic analysis, physiological data, as well as phenotypic and chemotaxonomic characterizations, it is concluded that the organism be classified as representing a novel species of the genus Nocardia, for which the name Nocardia rosealba sp. nov. is proposed. The type strain is NEAU-G4T (=CCTCC AA 2020038T=DSM 111936T).

Saccharothrix luteola sp. nov., a novel cellulose-degrading actinobacterium isolated from soil and emended description of the genus Saccharothrix.

A novel cellulose-degrading actinobacterium, designated strain NEAU-S10T, was isolated from soil collected from Chifeng, Inner Mongolia Autonomous Region, PR China, and characterized using a polyphasic approach. Pairwise similarity of the 16S rRNA gene sequence showed that strain NEAU-S10T was a representative of Saccharothrix and was closely related to Saccharothrix carnea NEAU-yn17T (99.2 %), Saccharothrix saharensis SA152T (99.0 %), Saccharothrix texasensis DSM 44231T (98.5 %) and Saccharothrix xinjiangensis NBRC 101911T (98.5 %). Physiological and chemotaxonomic characteristics of the strain further supported its affiliation to the genus Saccharothrix. The whole-cell sugars contained galactose, ribose and mannose. The polar lipids contained diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The predominant menaquinones were MK-9(H0), MK-9(H2), MK-9(H4) and MK-10(H4). The major fatty acids were iso-C16 : 0, C16 : 0, anteiso-C17 : 0, iso-C15 : 0 and iso-C17 : 0. The genomic DNA G+C content was 71.8 mol%. The levels of digital DNA-DNA hybridization between isolate and S. carnea NEAU-yn17T, S. saharensis SA152T and S. texasensis DSM 44231T were 40.1 % (37.6-42.6 %), 38.soap8 % (36.3-41.3 %) and 44.8 % (42.2-47.3 %) and the ANI values between them were determined to be 90.2, 89.8 and 91.7 %, the results indicated that strain NEAU-S10T could be distinguished from its reference strains. The assembled genome sequence of strain NEAU-S10T was found to be 10 305 394 bp long. The NCBI Prokaryotic Genome Annotation Pipeline (PGAP) revealed 8 994 protein-coding genes. Genomic analysis and Congo red staining test indicated that strain NEAU-S10T had the potential to degrade cellulose. The genomic and phenotypic results indicate that strain NEAU-S10T represents a novel species of the genus Saccharothrix, for which the name Saccharothrix luteola sp. nov. is proposed, with NEAU-S10T (=CCTCC AA 2020037T=JCM 34800T) as the type strain.

Role of Mitophagy-based TLR9 Signal Pathway in Neonatal Ventilator-induced Lung Injury.

The study focused on the role of mitophagy in neonatal ventilator-induced lung injury (VILI). Immunoassays were used to study the TLR9 signaling pathway of neonatal VILI, expected to provide a feasible solution for neonatal VILI. The mice were randomly divided into four groups, group A: spontaneous breathing group; group B: normal tidal volume (VT) group (VT=9mL/kg); group C: high VT group (VT=39mL/kg); and group D: ODN2088 (400µg/ Only) intervention + high VT group. The four groups were compared for the expression of inflammatory factors. It was found that as the culture time increased, the expression of TLR9, MyD88, and NF-κBp65 in the lung tissue of the large VT group was significantly higher than those in the spontaneous breathing group and normal VT group, and the differences were statistically significant; and TLR9 inhibitors could activate the TLR9-MyD88 signaling pathway to up-regulate the expression of NF-κB, mediating the release of inflammatory factors to cause VILI.

Enhanced Adsorption of Sulfonamides by Attapulgite-Doped Biochar Prepared with Calcination.

The extensive use of sulfonamides seriously threatens the safety and stability of the ecological environment. Developing green inexpensive and effective adsorbents is critically needed for the elimination of sulfonamides from wastewater. The non-modified biochar exhibited limited adsorption capacity for sulfonamides. In this study, the attapulgite-doped biochar adsorbent (ATP/BC) was produced from attapulgite and rice straw by calcination. Compared with non-modified biochar, the specific surface area of ATP/BC increased by 73.53−131.26%, and the average pore width of ATP/BC decreased 1.77−3.60 nm. The removal rates of sulfadiazine and sulfamethazine by ATP/BC were 98.63% and 98.24%, respectively, at the mass ratio of ATP to rice straw = 1:10, time = 4 h, dosage = 2 g∙L−1, pH = 5, initial concentration = 1 mg∙L−1, and temperature = 20 °C. A pseudo-second-order kinetic model (R2 = 0.99) and the Freundlich isothermal model (R2 = 0.99) well described the process of sulfonamide adsorption on ATP/BC. Thermodynamic calculations showed that the adsorption behavior of sulfonamides on the ATP/BC was an endothermic (ΔH > 0), random (ΔS > 0), spontaneous reaction (ΔG < 0) that was dominated by chemisorption (−20 kJ∙mol−1 > ΔG). The potential adsorption mechanisms include electrostatic interaction, hydrogen bonding, π−π interaction, and Lewis acid−base interactions. This study provides an optional material to treat sulfonamides in wastewater and groundwater.

Actinoplanes flavus sp. nov., a novel cellulase-producing actinobacterium isolated from coconut palm rhizosphere soil.

A novel cellulase-producing actinomycete, designated strain NEAU-H7T, was isolated from coconut palm rhizosphere soil collected from Wenchang City, Hainan Province, PR China. A polyphasic taxonomic study was carried out to establish the status of this strain. Results of 16S rRNA gene sequence analysis indicated that strain NEAU-H7T belonged to the genus Actinoplanes, with highest similarity to Actinoplanes hulinensis NEAU-M9T (99.2 % 16S rRNA gene sequence similarity). The diagnostic sugars in cell hydrolysates were determined to be ribose, galactose and mannose. The major fatty acids (>10%) were C16 : 0, C18 : 1 ω9c and C18 : 0. The predominant menaquinones were identified as MK-9(H4) and MK-9(H6). The major polar lipids were phosphatidylethanolamine, phosphatidylinositol and two phosphatidylinositol mannosides. The amino acid of the cell-wall peptidoglycan was determined to be meso-diaminopimelic acid. The DNA G+C content was 71.2 mol%. Phylogenetic analysis using 16S rRNA gene sequences showed that strain NEAU-H7T formed a stable phyletic line with A. hulinensis NEAU-M9T. However, whole-genome phylogeny showed strain NEAU-H7T formed a stable phyletic line with A. hulinensis NEAU-M9T (99.2%), Actinoplanes campanulatus DSM 43148T (98.6%), Actinoplanes capillaceus DSM 44859T (98.3%) and Actinoplanes lobatus DSM 43150T (97.6%). The digital DNA-DNA hybridization (dDDH) results between them were 53.6 (50.9-56.2), 54.1 (51.3-56.9), 53.1 (50.3-55.9) and 52.9 % (50.1-55.6 %), and whole-genome average nucleotide identity (ANI) values between them were 93.7, 93.6, 93.5 and 93.5 %. The low dDDH and ANI values demonstrated that strain NEAU-H7T could be distinguished from its reference strains. Moreover, genomic analysis indicated that the strain NEAU-H7T had the potential to decompose cellulose and produce bioactive compounds. On the basis of morphological, chemotaxonomic and phylogenetic characteristics, strain NEAU-H7T is proposed to represent a novel species of the genus Actinoplanes, with the name Actinoplanes flavus sp. nov. The type strain is NEAU-H7T (=CCTCC AA 2020034T=DSM 112042T).

Actinoplanes aureus sp. nov., a novel protease-producing actinobacterium isolated from soil.

A novel protease-producing actinobacterium, designated strain NEAU-A11T, was isolated from soil collected from Aohan banner, Chifeng, Inner Mongolia Autonomous Region, China, and characterised using a polyphasic approach. The hydrolytic enzymes, such as proteases, played critical roles in destruction of fungi by degrading the protein linkages to disrupt integrity in the cell wall. This suggested that the isolate could be a good biocontrol candidate against pathogens to control fungal diseases. On the basis of 16S rRNA gene sequence analysis, strain NEAU-A11T was indicated to belong to the genus Actinoplanes and was most closely related to Actinoplanes rectilineatus JCM 3194 T (98.9%). Cell walls contained meso-diaminopimelic acid as the diagnostic diamino acid and the whole-cell sugars were arabinose, xylose and glucose. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and two phosphatidylinositol mannosides. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H8). The major fatty acids were C18:0, C16:0, C18:1 ω9c, C17:0 and C15:0. Genome sequencing revealed a genome size of 10,742,096 bp, a G + C content of 70.5% and 9,514 protein-coding genes (CDS), including 102 genes coding for protease. Moreover, Genome analysis showed that strain NEAU-A11T contained 255 glycoside hydrolases (GHs), 152 glycosyl transferases (GTs), 40 carbohydrate esterases (CEs), 26 polysaccharide lyases (PLs), and 12 auxiliary activities (AAs) genes. Genome mining analysis using antiSMASH 5.0 led to the identification of 20 putative gene clusters responsible for the production of diverse secondary metabolites. Phylogenetic analysis using the 16S rRNA gene sequences showed that the strain formed a stable clade with A. rectilineatus JCM 3194 T in the genus Actinoplanes. Whole-genome phylogeny showed strain NEAU-A11T formed a stable phyletic line with Actinoplanes lutulentus DSM 45883 T (97.6%). However, whole-genome average nucleotide identity value between strain NEAU-A11T and its reference strains A. rectilineatus JCM 3194 T and A. lutulentus DSM 45883 T were found to be 81.1% and 81.6%, respectively. The levels of digital DNA-DNA hybridization between them were 24.6% (22.2-27.0%) and 24.8% (22.5-27.3%), respectively. The values were well below the criteria for species delineation of 70% for dDDH and 95-96% for ANI, suggesting that the isolate differed genetically from its closely related type strain. The content of G + C in genomic DNA was 70.5%, within the range of 67-76%. In addition, evidences from phenotypic, chemotaxonomic and genotypic studies indicated that strain NEAU-A11T represents a novel species of the genus Actinoplanes, for which the name Actinoplanes aureus sp. nov. is proposed, with NEAU-A11T (= CCTCC AA 2019063 T = JCM 33971 T) as the type strain.

Comparison of performance of two large-scale vertical-flow constructed wetlands treating wastewater treatment plant tail-water: Contaminants removal and associated microbial community.

The removal efficiency of contaminants in large-scale integrated vertical-flow constructed wetland (IVCW) and vertical-flow constructed wetland (VCW) for wastewater treatment plant (WWTP) tail-water was evaluated, and the microbial community was also investigated in this study. The results for 14 months study period indicated that 40.05% chemical oxygen demand (COD), 45.47% ammonia nitrogen (NH4+-N), 62.55% total phosphorus (TP), 55.53% total nitrogen (TN) and 57.20% total suspended solids (TSS) average removal efficiencies were achieved in the IVCW. There was a poor performance of TN removal in the VCW, with an average removal efficiency of 38.13%. There was no significant seasonal difference in TP removal, and a strong positive correlation between influent TP load and removed load. The high-throughput sequencing analysis revealed that Proteobacteria, Planctomycetes, Bacteroidetes and Acidobacteria were dominant in nature and wetland systems. The relative abundance of nitrifying bacteria, denitrifying bacteria and anammox bacteria confirmed that nitrification, denitrification and anammox may be the main processes for nitrogen removal in the IVCW.

Gold Nanoclusters-Decorated Zeolitic Imidazolate Frameworks with Reactive Oxygen Species Generation for Photoenhanced Antibacterial Study.

The serious threat of antibiotic-resistant bacterial infections has brought an urgent need for the development of new antibacterial nanomaterials. We encapsulate glutathione (GSH)-protected gold nanoclusters (AuNCs) in zeolitic imidazolate frameworks-8 (ZIF-8) and present their potential in antibacterial capabilities. Under white light irradiation, AuNCs-embedded ZIF-8 nanocomposites show assembly-enhanced emission and reactive oxygen species (ROS) generation. AuNCs@ZIF-8 exhibit almost complete inactivation of bacterial growth within 60 min of light irradiation. Scanning electron microscopic results show that AuNCs@ZIF-8 nanocomposites are captured by bacterial cells, and the leakage of alkaline phosphatase and nucleotides from bacteria demonstrate that the photoinduced ROS can easily destroy the bacterial surface and totally kill the bacteria. Herein, our antibacterial nanocomposites have photoenhanced bactericidal capability and show promising applications for sterilization.