Scleroglucan is a high-molecular water-soluble microbial exopolysaccharide and mainly applied in the fields of petroleum, food, medicine and cosmetics. The high molecular weight of scleroglucan produced by microbial fermentation leads to low solubility, high viscosity and poor dispersibility, thus bringing a series of difficulties to extraction, preservation and application. It is important to explore suitable degradation method to adjust the molecular weight of scleroglucan for expanding its industrial application. Taking Sclerotium rolfsii WSH-G01 as a model strain, in which functional annotations of the glucanase genes were conducted by whole genome sequencing. Based on design of culture system for culture system for differential expression of β-glucanase, endogenous β-glucanase genes in S. rolfsii WSH-G01 were excavated by transcriptomics analysis. Functions of these potential hydrolases were further verified. Finally, 14 potential endogenous hydrolase genes were obtained from S. rolfsii. After heterologous overexpression in Pichia pastoris, 10 soluble enzymes were obtained and 5 of them had the activity of laminarin hydrolysis by SDS-PAGE and enzyme activity analysis. Further investigation of the 5 endogenous hydrolases on scleroglucan degradation showed that enzyme GME9860 has positive hydrolysis effect. The obtained results provide references not only for obtaining low and medium molecular weight of scleroglucan with enzymatic hydrolysis, but also for producing different molecular weight of scleroglucan during S. rolfsii fermentation process with metabolic engineering.
Basidiomycota/genetics* ; Glucans ; Hydrolysis ; Saccharomycetales

OBJECTIVE: To explore clinical effect of VSD technology, coverage of artificial dermis and autograft for the treatment of limb skin soft tissue defect combined with bone or tendon exposed wound. METHODS: Eighteen patients suffered from limb skin soft tissue defect combined with bone or tendon exposed wound treated by three-step sequential method from January 2013 to June 2015. Among them, including 13 males and 5 females aged from 23 to 72 years old with an average of 34.6 years old; the time from injury to operation ranged from 1.5 to 5.0 hours with an average of 2.5 h. The area of skin and soft tissue injury ranged from 4.2 cm×3.1 cm to 7.4 cm×5.2 cm. Wound recovery and taken skin wound recovery were observed to evaluate clinical results. RESULTS: All patients were followed up from 5 to 16 months, with an average of 7.6 months. Deep bone tendon tissue of wounds were effectively recovered, artificial dermis survived, and quality of healed wound was tough and shape was good. Wound transplant flap was survived, no obvious scar tissue formation, appearance was flat, skin color was a little deeper than normal skin, the overall effect was satisfactory. CONCLUSIONS Three-step sequential method has good curative effect for patients suffered from limb skin soft tissue defect with bone or tendon exposed wound and refused to repair the flap, and has advantage of simple operation, operation risk, less invasive.
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Reconstructive Surgical Procedures ; Skin Transplantation ; Soft Tissue Injuries ; Surgical Flaps ; Tendons ; Treatment Outcome ; Young Adult

Pyrroloquinoline quinone (PQQ) is a bacterial dehydrogenase coenzyme. PQQ can promote body growth and regulate the function of free radical level of the body. It could be applied in food, medicine and other fields. Due to the extremely high cost of chemical synthesis, the production of PQQ by microbial fermentation attracted more and more attention. At present, the production titer of PQQ by fermentation method is too low to achieve industrial application. Due to the lack of a thorough understanding of the PQQ biosynthesis and its regulation mechanisms, and the lack of necessary genetic engineering modification methods for wild type strains, metabolic engineering of microorganisms to enhance PQQ production still lacks essential requirements. In this study, a PQQ-producing bacterium, Methylobacterium extorquens I-F2, was employed as a model strain. By integration of Atmospheric and room temperature plasma (ARTP) mutagenesis, flow cytometry sorting and high-throughput screening strategies, optimization of sample preparation and flow sorting process, a high-titer PQQ mutant strain was obtained. The titer of PQQ was increased by 98.02% compared with that of M. extorqunens I-F2. The process described here showed that the combination of the flow cytometry with high-throughput screening method can be used to obtain high-titer mutants more simply and rapidly, compared with genetic engineering and traditional screening methods.

L-tyrosine is one of three aromatic amino acids that are widely used in food, pharmaceutical and chemical industries. The transport system engineering provides an important research strategy for the metabolic engineering of Escherichia coli to breed L-tyrosine producing strain. The intracellular transport of L-tyrosine in E. coli is mainly regulated by two distinct permeases encoded by aroP and tyrP genes. The aroP and tyrP gene knockout mutants were constructed by CRISPR-Cas technique on the basis of L-tyrosine producing strain HGXP, and the effects of regulating transport system on L-tyrosine production were investigated by fermentation experiments. The fermentation results showed that the aroP and tyrP knockout mutants produced 3.74 and 3.45 g/L L-tyrosine, respectively, which were 19% and 10% higher than that of the original strain. The optimum induction temperature was determined to be 38 °C. Fed-batch fermentation was carried out on a 3-L fermentor. The L-tyrosine yields of aroP and tyrP knockout mutants were further increased to 44.5 and 35.1 g/L, respectively, which were 57% and 24% higher than that of the original strain. The research results are of great reference value for metabolic engineering of E. coli to produce L-tyrosine.
Escherichia coli ; Escherichia coli Proteins ; Gene Knockout Techniques ; Metabolic Engineering ; Tyrosine

Objective This study aimed to clarify the anti-influenza virus activity of Bingyanqing(BYQ),as well as to explore the mechanism of BYQ in treating influenza through network pharmacology and experimental verification.Methods The impact of BYQ on mortality,lung index,and viral load in an influenza mouse model was detected.We collected the ingredients and targets of BYQ formula by searching databases including TCMSP,Swiss Target Prediction and consulting the literature.The"ingredients-common target"network for anti-influenza effect of BYQ was constructed using Cytoscape software.The protein-protein interaction(PPI)network was constructed using the STRING database and Cytoscape software,and the core targets were screened.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were performed for common targets.The effect of BYQ on reducing influenza-induced oxidative damage,the expression of antioxidant and pro-oxidant enzyme,P65 phosphorylation and nuclear factor E2-related factor 2(Nrf2)nuclear translocation in vivo were investigated.Results BYQ significantly reduced mortality,lung index,pulmonary viral load and lung injury in a mouse model of influenza.We obtained one hundred and ninety-three of BYQ active compounds,which corresponded to three hundred and thirty-eight targets.There are 180 influenza-related targets among them.Nine targets,including IκBα kinase α(CHUK),IκBα kinase γ(IKBKG),NF-κB p65(RELA),tumor necrosis factor(TNF)and interleukin 6(IL6),were identified as potential core targets.GO analysis indicated that BYQ is involved in several biological functions,including antibacterial and antioxidant stress responses.KEGG analysis revealed the involvement of several viral and immune-related pathways for BYQ in treating influenza,including herpes simplex virus,influenza A virus,TNFα and toll-like receptor pathways.In vivo studies showed that high-dose BYQ significantly reduced pulmonary malondialdehyde(MDA)levels(P＜0.01)and increased total superoxide dismutase(SOD)activity(P＜0.001)in a mouse mode of influenza compared to oseltamivir phosphate.The treatment group with the combination of BYQ&oseltamivir phosphate had lower levels of NADPH oxidase 2(NOX2)and 4(NOX4)(P＜0.001),and higher levels of catalase(CAT)and glutathione peroxidase 4(GPX4)(P＜0.001)in the lungs than oseltamivir phosphate group.The combined treatment group showed more significant Nrf2 nuclear translocation(P＜0.05)than the oseltamivir phosphate group.However,there was no significant difference in P65 phosphorylation levels between the combination treatment group and the oseltamivir phosphate group(P＜0.05),but P65 phosphorylation levels in both groups were lower than in the model group(P＜0.05).Conclusion BYQ exhibits significant anti-influenza virus activity,manifests a dual effect by inhibiting the synthesis of pro-oxidant enzymes and promoting the antioxidant system,thereby alleviates the oxidative stress damage caused by influenza.

OBJECTIVE: To explore surgical methods and clinical effects of three different types of mini skin flap transplantation for repairing finger soft tissue with bone defect. METHODS: Thirty-three patients with finger soft tissue or bone defect were treated from December 2014 to October 2016, including 24 males and 9 females aged from 21 to 52 years old with an average of (36.42±5.70) years old, and soft tissue defect area ranged from 1.3 cm×1.8 cm to 2.3 cm×4.2 cm. According to damage degree, nature and patients' options, 15 finger of 15 cases were adopted retrograde dorsal metacarpal artery perforators fascia flap, 10 fingers of 9 cases were treated with free foot artery descending branch wrist skin flap, 9 fingers of 9 cases were treated with free the second toe details phalanges compound flap. Survival rate, postoperative complications and finger function assessed by Dargan functional criteria at the latest follow up were observed. RESULTS: All flaps were survived, both of donor site and recipient site were without deep infected. The donor site of one patient occurred necrotic, and the distal donor site of one patient occurred surface necrotic, then healed by active dressing change. All patients were followed up from 6 to 16 months with an average of(8.34±1.28) months. Two points of finger recognition were restored between 8 and 12 mm with an average of (8.84±0.43) mm, and the appearance, texture and sensory functions of skin flap were restored. No obvious complications were observed on the donor site. According to Dargan function evaluation of finger joints, 18 patients got excellent results, 14 moderate and 1 good. CONCLUSIONS Three kinds of mini skin flap could receive good results in repairing soft tissue of finger or bone defect. Reverse dorsal metacarpal artery perforator fascia flap is not necessary with anastomosing blood vessels and has advantages of safe, simple and high survival rate. Descending branch of superior cutaneous branch of free ulnar artery could cut multiple other perforator flaps simultaneously, and the scar is small and hidden. Dissociated the second toe combined metatarsal phalangeal flap could repair shape and function of finger to the maximum extent and donor site is hidden.
Adult ; Female ; Finger Injuries ; Humans ; Male ; Middle Aged ; Reconstructive Surgical Procedures ; Skin ; Skin Transplantation ; Soft Tissue Injuries ; Treatment Outcome ; Young Adult

Tumors pose a serious challenge to global public health. The sensitive and precise detection of tumor biomarkers is very important for early screening and diagnosis of cancers. DNAzymes with outstanding physical, chemical, and biological properties are widely applied in the design of biosensing strategies. By the use of sensing platforms such as fluorescence, electrochemistry, and surface-enhanced Raman scattering, DNAzymes facilitate the early screening and detection of tumors. This article summarizes the functional mechanism and common classifications of DNAzymes, and the updates of DNAzymes-based novel biosensing technologies within the field of liquid biopsy, expecting the technical challenges yet to be surmounted and future developmental directions.

This study investigated the quality markers(Q-markers) of Euphorbiae Humifusae Herba based on the analytic hierarchy process(AHP)-criteria importance through intercriteria correlation(CRITIC) comprehensive weighting method. The Q-markers evaluation system was constructed based on the AHP-CRITIC comprehensive weighting method with quantitative identification of Q-markers of Euphorbiae Humifusae Herba as the target layer. The index weights of the factor layer and the control layer were integrated based on the weights of three indicators(effectiveness, testability, and specificity) in the factor layer calculated by the AHP method and weights of eight indicators(anti-inflammatory inhibitory rate, coagulation shortening rate, anti-cancer inhibition rate, component degree value, component test batch, component average content, content variation coefficient, and number of medicinal materials retrieved according to components) in the control layer calculated by the CRITIC method. The comprehensive score of the chemical components of Euphorbiae Humifusae Herba was weighted and ranked to identify the Q-markers of Euphorbiae Humifusae Herba. In terms of comprehensive scores, top 10 potential Q-markers of Euphorbiae Humifusae Herba were ranked as cynaroside > quercetin > gallic acid > apigenin > luteolin > apigenin-7-O-glucoside > quercetin-7-O-glucoside > ellagic acid > astragalin > ethyl gallate. This study provides a reference for the quality control of Euphorbiae Humifusae Herba and a methodological reference for the quantitative identification of Q-markers of Chinese medicine.
Chromatography, High Pressure Liquid/methods* ; Quercetin ; Apigenin ; Quality Control ; Glucosides ; Drugs, Chinese Herbal/chemistry*