Whole-genome sequence of Pseudomonas benzopyrenica MLY92: isolation from diseased leaves of tobacco in China.

Here we present a sketch of the whole-genome sequence of Pseudomonas benzopyrenica. The strain comes from the leaf veins of a diseased tobacco plant. This study has significant research implications for gaining insights into the characteristics of microorganisms belonging to the genus Pseudomonas.

Active secretion of IL-33 from astrocytes is dependent on TMED10 and promotes central nervous system homeostasis.

Interleukin-33 (IL-33), secreted by astrocytes, regulates the synapse development in the spinal cord and hippocampus and suppresses autoimmune disease in the central nervous system (CNS). However, the mechanism of unconventional protein secretion of this cytokine remains unclear. In this study, we found that IFN-γ promotes the active secretion of IL-33 from astrocytes, and the active secretion of IL-33 from cytoplasm to extracellular space was dependent on interaction with transmembrane emp24 domain 10 (TMED10) via the IL-1 like cytokine domain in astrocytes. Knockout of Il-33 or its receptor St2 induced hippocampal astrocyte activation and depressive-like disorder in naive mice, as well as increased spinal cord astrocyte activation and polarization to a neurotoxic reactive subtype and aggravated passive experimental autoimmune encephalomyelitis (EAE). Our results have identified that IL-33 is actively secreted by astrocytes through the unconventional protein secretion pathway facilitated by TMED10 channels. This process helps maintain CNS homeostasis by inhibiting astrocyte activation.

IL-33 and HMGB1 modulate the progression of EAE via oppositely regulating each other.

Interleukin-33 (IL-33) and high mobility group box 1 (HMGB1) have been reported to play crucial and distinct roles in experimental autoimmune encephalomyelitis (EAE). However, little is known about their interaction in the progression of EAE. In this study, the dynamic expression and release of IL-33 and HMGB1 in different stages of EAE in vivo, and their interaction in vitro were explored. We found that HMGB1 was dominant in pre-onset stage of EAE, while IL-33 was dominant in peak stage. Moreover, both blockade of extracellular HMGB1 in the central nervous system (CNS) and conditional knockout of HMGB1 in astrocytes decreased IL-33 release. HMGB1 promoted the release of IL-33, while IL-33 reduced the release of HMGB1 from primary astrocytes in vitro. Taken together, IL-33 and HMGB1 in the CNS jointly participate in the EAE progression and the inhibitory effect of IL-33 on HMGB1 may be involved in the self-limiting of EAE.

IL-33 Contributes to the Pathological Changes of Hair Follicles in Psoriasis: A Potential Target for Psoriatic Alopecia.

Purpose: IL-33 is constitutively expressed in skin tissues. Alopecia, a T cells-driven disorder of the hair follicles (HFs), is a common complication in the development of psoriasis. However, the role of IL-33 in psoriatic alopecia remains uncovered. Here, we investigated the roles of IL-33 in inducing pathological changes of hair follicles in psoriasis. Patients and Methods: Clinical samples and imiquimod (IMQ)-induced psoriatic mice samples were used to investigate the pathological changes and T-cell infiltration of HFs. By using immunohistochemistry staining, the distribution and expression alteration of IL-33 in HFs were determined. Next, by using IL-33 and ST2 knockout mice, we investigated the role of IL-33/ST2 axis in the pathological changes of HFs in psoriasis. Meanwhile, recombinant IL-33 protein was subcutaneous injected to confirm its effect. Finally, RNA sequencing was used to clarify the genes and signaling pathways that involved in this process. Differentially expressed genes were further verified by RT-PCR in cultured HFs in vitro. Results: We found that the pathological changes of HFs and T cells infiltration in imiquimod-induced psoriatic mice were similar to that in psoriasis patients. The IL-33 positive keratinocytes in the outer root sheath of HFs were increased in both psoriasis patients and psoriatic model mice compared with the controls. By using gene knockout mice, we found that the pathological changes and T cell infiltration were attenuated in IL-33-/- and ST2-/- psoriatic model mice. In addition, subcutaneous injection of recombinant IL-33 exacerbated the pathological changes of HFs and T cell infiltration. RNA sequencing and RT-RCR revealed that IL-33 upregulated the transcription of genes related to keratinocytes proliferation and T lymphocytes chemotaxis. Conclusion: Our study identifies that IL-33 promotes the pathological changes of HFs in psoriasis, which contributes to psoriatic alopecia. Inhibition of IL-33 may be a potential therapeutic approach for psoriatic alopecia.

Effect of GO on the Structure and Properties of PEG/Biochar Phase Change Composites.

In recent years, phase change materials (PCMs) have been widely used in waste heat utilization, buildings, and solar and wind energy, but with a huge limitation from the low thermal conductivity, photothermal conversion efficiency, and low latent heat. Organic PCMs are eyecatching because of its high latent heat storage capability and reliability, but they still suffer from a lack of photothermal conversion and sharp stability. Here, we prepared sharp-stable PCMs by establishing a carbon material frame system consisting of graphene oxide (GO) and biochar. In particular, surfactants (CTAB, KH-560 and KH-570) were employed to improve the dispersity of GO in PEG. The differential scanning calorimetry results shows that the latent heat of PEG modified by CTAB grafted GO (PGO-CTAB) was the highest (191.36 J/g) and increased by 18.31% compared to that of pure PEG (161.74 J/g). After encapsulation of PGO-CTAB in biochar, the obtained composite PCM with the amount of biochar and PGO-CTAB in weight ratio 4:6 (PGO-CTAB/CS6(6)) possesses relatively high latent heat 106.51 J/g with good leak resistance and thermal stability, and with obviously enhanced thermal conductivity (0.337 W/(m·K)) and photothermal conversion efficiency (77.43%), which were higher than that of PEG6000 (0.325 W/(m·K), 44.63%). The enhancement mechanism of heat transfer and photothermal conversion on the composite PCM is discussed.

Effect of steam explosion pretreatment on the composition and bioactive characteristic of phenolic compounds in Chrysanthemum morifolium Ramat cv. Hangbaiju powder with various sieve fractions.

Steam explosion (SE) pretreatment is an efficient technique to promote the fiber degradation and disrupt materials' cell wall. In this study, the effect of SE pretreatment on the changes in phenolic profile, and the in vitro digestion property of a Chinese indigenous herb "Hangbaiju" (HBJ) powder with various sieve fractions (150-, 180-, 250-, 425-, and 850-µm sieves) were studied. After SE pretreatment, the morphological structure, color attributes, and composition of phenolic compounds were altered significantly (p < .05). The composition and content of phenolic compounds were strongly correlated with particle sizes. The higher extraction yield of phenolic compounds was reached in the intermediate sieve fraction (ca. 250-µm sieves). During in vitro digestion, the changes in phenolic compounds were significant due to the transition from an acidic to the alkaline environment (p < .05). Based on the multivariate statistical analysis, apigenin-7-O-glucoside, luteolin-7-O-glucoside, and linarin, were viewed as the characteristic compounds among various samples. The results highlighted that the phytochemical properties mainly including the composition of phenolic compounds, and in vitro digestion properties of HBJ powder with intermediate sieve fraction could be improved after SE pretreatment.

Effects of biochar pyrolysis temperature on thermal properties of polyethylene glycol/biochar composites as shape-stable biocomposite phase change materials.

The characteristics of biochar are of great significance to its application in the field of phase change energy storage. The objective of this research was to explore the effects of pyrolysis temperature on the characteristics of a biochar matrix and further on the heat energy storage properties of the promising green biochar-supported shape-stable biocomposite PCMs (ss-BCPCMs). Corn straw biochars (CSBCs) obtained under different pyrolysis conditions were loaded with polyethylene glycol (PEG) by an ultrasound-assisted vacuum impregnation method. The micro-morphology, specific surface area, pore structure and surface properties of biochar have been characterized and analyzed by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) method and Fourier transform infrared spectroscopy (FTIR). The thermal properties (chemical stability, latent heat storage, thermal conductivity, thermal stability, and thermal insulation) of PEG/CSBC composites have been characterized by FTIR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and laser flash analysis (LFA). The study revealed that both pore structure and surface activity of biochar are key factors affecting the energy storage performance of biochar-based ss-BCPCMs. The obtained PEG/CSBC composite showed a high latent heat storage up to 100.2 J g-1, good shape stability and leakage resistance, suggesting its high thermal storage stability that is beneficial for thermal energy storage applications. In addition, its excellent photothermal conversion efficiency (68.95%) provides application potential in photothermal energy storage.

Bioeffects of static magnetic fields on the growth and metabolites of C. pyrenoidosa and T. obliquus.

Microalgae is one of the most potential materials for biofuels and dietary supplements. However, the high cost of cultivation has always restrained its commercial application. Static magnetic fields (SMF), with the advantages of low operational cost and non-toxic secondary pollution, exhibits great potential in the promotion to the microalgal growth and metabolism. In this study, the dynamic patterns on the biomass and metabolites including pigment, protein, carbohydrate, lipid and fatty acids of C. pyrenoidosa and T. obliquus under 30 mT SMF for 15 days at 24 h·d-1 were explored. Results demonstrated that SMF triggered the growth of C. pyrenoidosa and T. obliquus by 32.8% and 31.5%, respectively. SMF significantly stimulated protein synthesis by 44.3%, whereas decreased carbohydrate by 19.7% and lipid by 23.4% in C. pyrenoidosa (p < 0.05), indicating that SMF was a promising approach for inducing intracellular carbon partition to the protein synthetic pathway. The carbohydrate content exhibited a significant lower by 43.7% in T. obliquus under SMF than that of the control (p < 0.05), while no significant changes were observed in either the protein or the lipid. SMF applied for the two microalgae had negative effects on the fatty acids (MUFAs, PUFAs, and TFAs). The results indicated that SMF could not only significantly accelerate the growth of the two microalgae, but also influence their metabolites.

Isolation of Penicillium expansum WH-3 for the production of L(+)-tartaric acid.

The L(+)-form of tartaric acid (L(+)-TA) exists extensively in nature, and is widely used in the food, chemical, textile, building, and pharmaceutical industries (Su et al., 2001). The main method for L(+)-TA production is microbial transformation by cis-epoxysuccinate hydrolase (CESH), which can catalyze the asymmetric hydrolysis of cis-epoxysuccinic acid or its salts to TA or tartrate (Bao et al., 2019). Seventeen species containing CESH have been isolated so far. However, most species for L(+)-TA production have been reported from bacteria (Xuan and Feng, 2019). The only fungus isolated from soil by our lab recently, that could be used as catalyst for the process under acidic condition, is Aspergillus niger WH-2 (Bao et al., 2020). In order to find strains with new characteristics, this study attempted to isolate a new CESH source from fungi and investigate its application value.

Isolation of a novel strain Aspergillus niger WH-2 for production of L(+)-tartaric acid under acidic condition.

OBJECTIVES: To isolate a novel cis-epoxysuccinate hydrolase (CESH)-producing fungus for production of L( +)-tartaric acid, before this, all strains were selected from bacteria. RESULTS: A CESH-producing fungus was first isolated from soil and identified as Aspergillus niger WH-2 based on its morphological properties and ITS sequence. The maximum activity of hyphaball and fermentation supernatants was 1278 ± 64 U/g and 5.6 ± 0.3 U/mL, respectively, in a 5 L fermenter based on the conditions optimized on the flask. Almost 70% of CESH was present in hyphaball, which maintained 40% residual activity at pH 4.0 and showed a good acid stability (pH 3.0-10.0), high conversion rate (> 98%), and enantioselectivity (EE > 99.6%). However, the reported CESHs from bacteria can't be catalyzed under acidic conditions. CONCLUSIONS: The Aspergillus niger WH-2 was the first reported CESH-producing fungus, which could biosynthesize L ( +)-tartaric acid under acidic conditions and provide an alternative catalyst and process.

Cloning and characterization of an oxiranedicarboxylate hydrolase from Labrys sp. WH-1.

OBJECTIVE: This study aimed to clone and characterize the oxiranedicarboxylate hydrolase (ORCH) from Labrys sp. WH-1. METHODS: Purification by column chromatography, characterization of enzymatic properties, gene cloning by protein terminal sequencing and polymerase chain reaction (PCR), and sequence analysis by secondary structure prediction and multiple sequence alignment were performed. RESULTS: The ORCH from Labrys sp. WH-1 was purified 26-fold with a yield of 12.7%. It is a monomer with an isoelectric point (pI) of 8.57 and molecular mass of 30.2 kDa. It was stable up to 55 °C with temperature at which the activity of the enzyme decreased by 50% in 15 min (T5015) of 61 °C and the half-life at 50 °C (t1/2, 50 °C) of 51 min and was also stable from pH 4 to 10, with maximum activity at 55 °C and pH 8.5. It is a metal-independent enzyme and strongly inhibited by Cu2+, Ag+, and anionic surfactants. Its kinetic parameters (Km, kcat, and kcat/Km) were 18.7 mmol/L, 222.3 s-1, and 11.9 mmol/(L·s), respectively. The ORCH gene, which contained an open reading frame (ORF) of 825 bp encoding 274 amino acid residues, was overexpressed in Escherichia coli and the enzyme activity was 33 times higher than that of the wild strain. CONCLUSIONS: The catalytic efficiency and thermal stability of the ORCH from Labrys sp. WH-1 were the best among the reported ORCHs, and it provides an alternative catalyst for preparation of L(+)-2,3-dihydrobutanedioic acid.

Broccoli ingestion increases the glucosinolate hydrolysis activity of microbiota in the mouse gut.

After consuming broccoli, isothiocyanates can be produced by the hydrolytic action of myrosinase from plant and/or microbiota. Using male C57BL/6 mice, the present study investigated the effects of broccoli ingestion on the myrosinase-like activity, NAD(P)H:quinone oxidoreductase 1 (NQO1) activity, diversity and composition of the gut microbiota. Compared with the control group, continuously feeding raw or hydrolysed broccoli increased the myrosinase-like activities of the colon and caecum contents, and also improved the NQO1 activity of the colon mucosa. Significant difference between the broccoli and control feeding groups were found. 16S rRNA gene sequencing indicated that broccoli ingestion profoundly affected the composition of the gut bacteria community. The correlation between the gut bacterial community composition and microbiota myrosinase-like activity was also studied. However, one type of glucosinolate, sinigrin, had no effect on these activities, indicating that broccoli component(s), other than glucosinolate, had increased the NQO1 and myrosinase-like activities.

Hydrolysis before Stir-Frying Increases the Isothiocyanate Content of Broccoli.

Broccoli is found to be a good source of glucosinolates, which can be hydrolyzed by endogenous myrosinase to obtain chemopreventive isothiocyanates (ITCs); among them, sulforaphane (SF) is the most important agent. Studies have shown that cooking greatly affects the levels of SF and total ITCs in broccoli. However, the stability of these compounds during cooking has been infrequently examined. In this study, we proved that the half-lives of SF and total ITCs during stir-frying were 7.7 and 5.9 min, respectively, while the myrosinase activity decreased by 80% after stir-frying for 3 min; SF and total ITCs were more stable than myrosinase. Thus, the contents of SF and total ITCs decreased during stir-frying largely because myrosinase was destroyed. Subsequently, it was confirmed that compared to direct stir-frying, hydrolysis of glucosinolates in broccoli for 90 min followed by stir-frying increased the SF and total ITC concentration by 2.8 and 2.6 times, respectively. This method provides large quantities of beneficial ITCs even after cooking.

Antioxidant Capacities of Fractions of Bamboo Shaving Extract and Their Antioxidant Components.

This research was conducted for evaluation of antioxidant activities of four fractions from bamboo shavings extract (BSE) and their antioxidant components. The antioxidant capacities of BSE and four fractions on ABTS, DPPH, FRAP and total antioxidant capacity assays exhibited the following descending order: DF > n-butanol fraction (BF) > BSE ≈ ethyl acetate fraction (AF) > water fraction (WF). Among the identified phenolic compounds, caffeic acid exhibited the highest antioxidant capacities on DPPH, FRAP and total antioxidant capacity assays. An extremely significant positive correlation between the antioxidant activities with the contents of total flavonoids, total phenolic acids, or total phenolics was observed in this study. The result indicated that the bamboo shaving extract and its solvent fractions could act as natural antioxidants in light of their potent antioxidant activities.

CoinFold: a web server for protein contact prediction and contact-assisted protein folding.

CoinFold (http://raptorx2.uchicago.edu/ContactMap/) is a web server for protein contact prediction and contact-assisted de novo structure prediction. CoinFold predicts contacts by integrating joint multi-family evolutionary coupling (EC) analysis and supervised machine learning. This joint EC analysis is unique in that it not only uses residue coevolution information in the target protein family, but also that in the related families which may have divergent sequences but similar folds. The supervised learning further improves contact prediction accuracy by making use of sequence profile, contact (distance) potential and other information. Finally, this server predicts tertiary structure of a sequence by feeding its predicted contacts and secondary structure to the CNS suite. Tested on the CASP and CAMEO targets, this server shows significant advantages over existing ones of similar category in both contact and tertiary structure prediction.

RaptorX-Property: a web server for protein structure property prediction.

RaptorX Property (http://raptorx2.uchicago.edu/StructurePropertyPred/predict/) is a web server predicting structure property of a protein sequence without using any templates. It outperforms other servers, especially for proteins without close homologs in PDB or with very sparse sequence profile (i.e. carries little evolutionary information). This server employs a powerful in-house deep learning model DeepCNF (Deep Convolutional Neural Fields) to predict secondary structure (SS), solvent accessibility (ACC) and disorder regions (DISO). DeepCNF not only models complex sequence-structure relationship by a deep hierarchical architecture, but also interdependency between adjacent property labels. Our experimental results show that, tested on CASP10, CASP11 and the other benchmarks, this server can obtain ∼84% Q3 accuracy for 3-state SS, ∼72% Q8 accuracy for 8-state SS, ∼66% Q3 accuracy for 3-state solvent accessibility, and ∼0.89 area under the ROC curve (AUC) for disorder prediction.

Effect of carboxyethylation degree on the adsorption capacity of Cu(II) by N-(2-carboxyethyl)chitosan from squid pens.

Chitosan was prepared by N-deacetylation of squid pens ß-chitin, and N-carboxyethylated chitosan (N-CECS) with different degrees of substitution (DS) were synthesized. DS values of N-CECS derivatives calculated by (1)H nuclear magnetic resonance (NMR) spectroscopy were 0.60, 1.02 and 1.46, respectively. The adsorption capacity of Cu(II) by N-CECS correlated well with the DS and pH ranging from 3.2 to 5.8. The maximum Cu(II) adsorption capacity (qm) of all three N-CECS at pH 5.4 was 207.5mg g(-1), which was 1.4-fold higher than that of chitosan. The adsorption equilibrium process was better described by the Langmuir than Freundlich isotherm model. Adsorption of Cu(II) ion onto N-CECS followed a pseudo-second order mechanism with chemisorption as the rate-limiting step. In a ternary adsorption system, the adsorption capacity of Cu(II) by N-CECS also presented high values, and qm for Cu(II), Cd(II), and Pb(II) were 150.2, 28.8, and 187.9mg g(-1), respectively.

Preparation, characterization, and biochemical activities of N-(2-Carboxyethyl)chitosan from squid pens.

Chitosan was prepared by alkaline N-deacetylation of ß-chitin from squid pens, and N-carboxyethylated derivatives (N-CECS) with different degrees of substitution (DS) were synthesized. The carboxyethylation of the polysaccharide was identified by Fourier transform infrared, (1)H and (13)C nuclear magnetic resonance (NMR), and X-ray diffraction analyses. The DS of the derivatives was calculated by (1)H NMR and elemental analysis. All three N-CECS samples showed good water solubility at pH > 6.5. The antioxidant properties and bile acid binding capacity of the derivatives were studied in vitro. The highest bile acid binding capacity of all N-CECS reached 36.9 mg/g, which was 2.6-fold higher than that of chitosan. N-CECS showed a stronger scavenging effect on 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical ability, and EC50 values were below 2 mg/mL. The scavenging ability of N-CECS against superoxide radicals correlated well with the DS and concentration of N-CECS. These results indicated that N-carboxyethylation is a possible approach to prepare chitosan derivatives with desirable in vitro biochemical properties.

Functional components of bamboo shavings and bamboo leaf extracts and their antioxidant activities in vitro.

This study was designed to detect characteristic compounds and evaluate the free radical scavenging capacity of the bamboo leaves extract and bamboo shavings extract (BSE). The antioxidant capacity of bamboo leaf n-butanol fraction (AOB) exhibited the highest total phenolic content (49.93%), total flavonoids content (24.11%), and characteristic flavonoids and phenolic acids, such as chlorogenic acid, caffeic acid, ferulic acid, p-coumaric acid, orientin, homoorientin, vitexin, and isovitexin. Available data obtained with in vitro models suggested that AOB had higher free radical scavenging capacity with IC(50) values of 1.04, 4.48, 5.37, and 1.12 µg/mL on DPPH(•), O(2)(•-), (•)OH, and H(2)O(2), respectively, than the other two extracts, bamboo leaf water extract and BSE. The results indicated that the extracts from different parts of the bamboo possess excellent antioxidant activity, which can be used potentially as a readily accessible and valuable bioactive source of natural antioxidants.

Effect of quaternization degree on physiochemical and biological activities of chitosan from squid pens.

Chitosan was prepared by alkaline N-deacetylation of ß-chitin from squid pens, and N-(2-hydroxy) propyl-3-trimethyl ammonium chitosan chloride (HTCC) derivatives, with different degrees of quaternization (DQ) ranging from 0.77 to 1.06, were synthesized. It was identified by FT-IR, 1H NMR and XRD analysis. All of the HTCC showed good water solubility in a wide pH range. The moisture absorption and retention abilities of all the HTCC were much better than that of the chitosan. The moisture absorption and retention values of all the HTCC at 43% RH for 24 h were above 49% and 92%, respectively. The scavenging ability of HTCC against hydroxyl and ABTS radicals improved with increasing concentration. The effectiveness of HTCC against hydroxyl radicals was lower than that of chitosan. These results indicated that HTCC, which has a much better moisture absorption and retention capacity, may act as a potential moisturizer in vitro.