A magnetic biocatalyst based on mussel-inspired polydopamine and its acylation of dihydromyricetin

A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles (PD-MNPs) was prepared and characterized. The widely used Aspergillus niger lipase (ANL) was immobilized on the PD-MNPs (ANL@PD-MNPs) with a protein loading of 138 mg/g and an activity recovery of 83.6% under optimized conditions. For the immobilization, the pH and immobilization time were investigated. The pH and thermal and storage stability of the ANL@PD-MNPs significantly surpassed those of free ANL. The ANL@PD-MNPs had better solvent tolerance than free ANL. The secondary structure of free ANL and ANL@PD-MNPs was analyzed by infrared spectroscopy. A kinetic study demonstrated that the ANL@PD-MNPs had enhanced enzyme-substrate affinity and high catalytic efficiency. The ANL@PD-MNPs was applied as a biocatalyst for the regioselective acylation of dihydromyricetin (DMY) in DMSO and gave a conversion of 79.3%, which was higher than that of previous reports. The ANL@PD-MNPs retained over 55% of its initial activity after 10 cycles of reuse. The ANL@PD-MNPs were readily separated from the reaction system by a magnet. The PD-MNPs is an excellent support for ANL and the resulting ANL@PD-MNPs displayed good potential for the efficient synthesis of dihydromyricetin-3-acetate by enzymatic regioselective acylation

Enhancing Higher Order Question of Student Through Problem Based Learning at Grade X MIA 6 of SMA N 4 Surakarta

The research aims to enhance the Higher Order Question of student through problem based learning in Biology at Grade X MIA 6 of SMA N 4 Surakarta. The research was a four-cycle action research conducted in academic year 2014/2015. All questions were analyzed based on revised Bloom Taxonomy. Data were validated using triangulation method. The result of the research showed that problem based learning effectively enhance student\u27s High Order Question (C4-C6). The percentage of each High Order Question (C4-C6) in pre cycle were 0%. The percentage of C4 type question at first cycle (73,14%), second cycle (52,13%), third cycle (56,05%), and fourth cycle (58,42%). The percentage of each High Order Question (C4-C6) in pre cycle were 0%. The percentage of C5 type question at first cycle (18,37%), second cycle (9,57%), third cycle (10,30%), and fourth cycle (58,42%). The percentage of each High Order Question (C4-C6) in pre cycle were 0%. The percentage of C6 type question at first cycle (8,16%), second cycle (38,30%), third cycle (41,18%) and fourth cycle (25,74%)

Production of microbial oil with high oleic acid content by Trichosporon capitatum

Microbial oils with high unsaturated fatty acids content, especially oleic acid content, are good feedstock for high quality biodiesel production. Trichosporon capitatum was found to accumulate lipid with around 80% oleic acid and 89% total unsaturated fatty acids content on nitrogen-limited medium. In order to improve its lipid yield, effects of medium components and culture conditions on cell growth and lipid accumulation were investigated. Optimization of media resulted in a 61% increase in the lipid yield of T. capitatum after cultivation at 28 °C and 160 rpm for 6 days. In addition, T. capitatum could grow well on cane molasses and afford a lipid yield comparable to that on synthetic nitrogen-limited medium. The biodiesel from the microbial oil produced by T. capitatum on cane molasses displayed a low cold filter plugging point (-15 °C), and so T. capitatum might be a promising strain to provide lipid suitable for high quality biodiesel production.Trichosporon capitatum Microbial oil High oleic acid content Cane molasses Biodiesel

Efficient Hydrolysis of Cellulose over a Novel Sucralose-Derived Solid Acid with Cellulose-Binding and Catalytic Sites

A new sucralose-derived solid acid catalyst (SUCRA-SO₃H), containing −Cl and −SO₃H functional groups, has been shown to be highly effective for hydrolyzing β-1,4-glucans, completely hydrolyzing cellobiose (<b>1</b>) into glucose (<b>2</b>) in 3 h and converting the microcrystalline cellulose pretreated by the ionic liquid into glucose (<b>2</b>) with a yield of around 55% and a selectivity of 98% within 24 h at a relatively moderate temperature (393K). The enhanced adsorption capacity that the catalyst has for glucan by virtue of the presence of chloride groups that act as cellulose-binding sites offers the possibility of resolving the existing bottleneck in heterogeneous catalysis to hydrolyze cellulose, namely, the low accessibility of cellulose to the reaction position in typical solid catalysts. The apparent activation energy for hydrolysis of cellobiose (<b>1</b>) with SUCRA-SO₃H was 94 kJ/mol, which was much lower than that with sulfuric acid (133 kJ/mol) and the corresponding sucrose-derived catalyst (SUCRO-SO₃H) without chlorine groups (114 kJ/mol)

Hydrolase mimic via second coordination sphere engineering in metal-organic frameworks for environmental remediation

Abstract Enzymes achieve high catalytic activity with their elaborate arrangements of amino acid residues in confined optimized spaces. Nevertheless, when exposed to complicated environmental implementation scenarios, including high acidity, organic solvent and high ionic strength, enzymes exhibit low operational stability and poor activity. Here, we report a metal-organic frameworks (MOFs)-based artificial enzyme system via second coordination sphere engineering to achieve high hydrolytic activity under mild conditions. Experiments and theoretical calculations reveal that amide cleavage catalyzed by MOFs follows two distinct catalytic mechanisms, Lewis acid- and hydrogen bonding-mediated hydrolytic processes. The hydrogen bond formed in the secondary coordination sphere exhibits 11-fold higher hydrolytic activity than the Lewis acidic zinc ions. The MOFs exhibit satisfactory degradation performance of toxins and high stability under extreme working conditions, including complicated fermentation broth and high ethanol environments, and display broad substrate specificity. These findings hold great promise for designing artificial enzymes for environmental remediation

Lactiplantibacillus plantarum enables blood urate control in mice through degradation of nucleosides in gastrointestinal tract

Abstract Background Lactobacillus species in gut microbiota shows great promise in alleviation of metabolic diseases. However, little is known about the molecular mechanism of how Lactobacillus interacts with metabolites in circulation. Here, using high nucleoside intake to induce hyperuricemia in mice, we investigated the improvement in systemic urate metabolism by oral administration of L. plantarum via different host pathways. Results Gene expression analysis demonstrated that L. plantarum inhibited the activity of xanthine oxidase and purine nucleoside phosphorylase in liver to suppress urate synthesis. The gut microbiota composition did not dramatically change by oral administration of L. plantarum over 14 days, indicated by no significant difference in α and β diversities. However, multi-omic network analysis revealed that increase of L. plantarum and decrease of L. johnsonii contributed to a decrease in serum urate levels. Besides, genomic analysis and recombinant protein expression showed that three ribonucleoside hydrolases, RihA–C, in L. plantarum rapidly and cooperatively catalyzed the hydrolysis of nucleosides into nucleobases. Furthermore, the absorption of nucleobase by intestinal epithelial cells was less than that of nucleoside, which resulted in a reduction of urate generation, evidenced by the phenomenon that mice fed with nucleobase diet generated less serum urate than those fed with nucleoside diet over a period of 9-day gavage. Conclusion Collectively, our work provides substantial evidence identifying the specific role of L. plantarum in improvement of urate circulation. We highlight the importance of the enzymes RihA–C existing in L. plantarum for the urate metabolism in hyperuricemia mice induced by a high-nucleoside diet. Although the direct connection between nucleobase transport and host urate levels has not been identified, the lack of nucleobase transporter in intestinal epithelial cells might be important to decrease its absorption and metabolization for urate production, leading to the decrease of serum urate in host. These findings provide important insights into urate metabolism regulation. Video Abstrac

Tumor-derived CXCL5 promotes human colorectal cancer metastasis through activation of the ERK/Elk-1/Snail and AKT/GSK3β/β-catenin pathways

Abstract Background Metastasis is a major cause of death in human colorectal cancer patients. However, the contribution of chemokines in the tumor microenvironment to tumor metastasis is not fully understood. Methods Herein, we examinined several chemokines in colorectal cancer patients using chemokine ELISA array. Immunohistochemistry was used to detect expression of CXCL5 in colorectal cancer patients tissues. Human HCT116 and SW480 cell lines stably transfected with CXCL5, shCXCL5 and shCXCR2 lentivirus plasmids were used in our in vitro study. Immunoblot, immunofluorescence and transwell assay were used to examine the molecular biology and morphological changes in these cells. In addition, we used nude mice to detect the influence of CXCL5 on tumor metastasis in vivo. Results We found that CXCL5 was overexpressed in tumor tissues and associated with advanced tumor stage as well as poor prognosis in colorectal cancer patients. We also demonstrated that CXCL5 was primarily expressed in the tumor cell cytoplasm and cell membranes, which may indicate that the CXCL5 was predominantly produced by cancer epithelial cells instead of fibroblasts in the tumor mesenchyme. Additionally, overexpression of CXCL5 enhanced the migration and invasion of colorectal cancer cells by inducing the epithelial-mesenchymal transition (EMT) through activation of the ERK/Elk-1/Snail pathway and the AKT/GSK3β/β-catenin pathway in a CXCR2-dependent manner. The silencing of Snail and β-catenin attenuated CXCL5/CXCR2-enhanced cell migration and invasion in vitro. The elevated expression of CXCL5 can also potentiate the metastasis of colorectal cancer cells to the liver in vivo in nude mice intrasplenic injection model. Conclusion In conclusion, our findings support CXCL5 as a promoter of colorectal cancer metastasis and a predictor of poor clinical outcomes in colorectal cancer patients

Data_Sheet_1_Heterogeneity of psychosocial functioning in patients with bipolar disorder: Associations with sociodemographic, clinical, neurocognitive and biochemical variables.PDF

ObjectiveThis study aims to identify the functional heterogeneity in fully or partially remitted patients with bipolar disorder and explore the correlations between psychosocial functioning and sociodemographic, clinical, neurocognitive and biochemical variables.MethodsOne hundred and forty fully or partially remitted patients with bipolar disorder (BD) and seventy healthy controls were recruited. The patients were grouped into different profiles based on the Functioning Assessment Short Test (FAST) domain scores by hierarchical cluster analysis. The characteristics of subgroups and the correlations between psychosocial functioning and sociodemographic, clinical, neurocognitive and biochemical variables in each cluster were then analyzed.ResultsThere were three subgroups in fully or partially remitted patients with BD: the lower functioning group (LF), performed global functioning impairments; the moderate functioning group (MF), presented selective impairments in functional domains; and the good functioning subgroup (GF), performed almost intact functioning. Among the three subgroups, there were differences in FAST domains, sociodemographic variables, clinical variables, some neurocognitive domains and several biochemical indexes.ConclusionsThe study successfully identified three functional subgroups. The characteristics of discrete subgroups and the specific clinical factors, neurocognitive domains and biochemical indexes that are correlated with functional subgroups will allow for making tailored interventions to promote functional recovery and improve the quality of life.</p

Additional file 2 of Lactiplantibacillus plantarum enables blood urate control in mice through degradation of nucleosides in gastrointestinal tract

Additional file 2: Figure S1. Changes in metabolic parameters due to high nucleosides diet and L. plantarum supplementation in mice. Supplementary Fig. 2. Changes in gut microbiota due to high nucleosides diet and L. plantarum supplementation in mice. Supplementary Fig. 3. L. plantarum affecting the gut metabolites. Supplementary Fig. 4. Metagenomic functional annotation and classification of L. plantarum in KEGG (A) and in COG (B). Supplementary Fig. 5. Identification of production of inosine hydrolyzed by L. plantarum. Supplementary Fig. 6. Established Caco-2 cell monolayer for nucleosides and nucleobases transport. Supplementary Fig. 7. Gene sequences alignment of RihA–C from L. plantarum with other organisms

Additional file 1 of Lactiplantibacillus plantarum enables blood urate control in mice through degradation of nucleosides in gastrointestinal tract

Additional file 1: Table S1. Primer sequence of genes in this work. Table S2. Fifteen differential genera in mice supplemented L. plantarum when compared with HNS mice. Table S3. Taxonomy of six microbes using NCBI Nucleotide BLAST analysis tool. Table S4. Three genes involved with nucleoside degradation in L. plantarum. Table S5. Annotated genes contributed to the nucleotide and nucleoside metabolism, which showed that no enzyme in L. plantarum enable to catalyze the transformation of guanine and hypoxanthine into xanthine and resultant urate. Table S6. Genes involved with purine permeation in L. plantarum. Table S7. Permeation for nucleobases in L. plantarum within 2 hours. Table S8. Solubility of nucleosides and nucleobases in water. Table S9. Nodes information in multi-omic network analysis given by Fig. 2A. Table S10. Edges information in multi-omic network analysis given by Fig. 2A. Table S11. Nodes information in multi-omic network analysis given by Fig. S3C. Table S12. Edges information in multi-omic network analysis given by Fig. 3C