Backbone Cyclization of Flavin Mononucleotide-Based Fluorescent Protein Increases Fluorescence and Stability

Lin Tingting,Ge Yuanyuan,Gao Qing,Zhang Di,Chen Xiaofeng,Hu Yafang,Fan Jun 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.12

Flavin mononucleotide-binding proteins or domains emit cyan-green fluorescence under aerobic and anaerobic conditions, but relatively low fluorescence and less thermostability limit their application as reporters. In this work, we incorporated the codon-optimized fluorescent protein from Chlamydomonas reinhardtii with two different linkers independently into the redox-responsive split intein construct, overexpressed the precursors in hyperoxic Escherichia coli SHuffle T7 strain, and cyclized the target proteins in vitro in the presence of the reducing agent. Compared with the purified linear protein, the cyclic protein with the short linker displayed enhanced fluorescence. In contrast, cyclized protein with incorporation of the long linker including the myc-tag and human rhinovirus 3C protease cleavable sequence emitted slightly increased fluorescence compared with the protein linearized with the protease cleavage. The cyclic protein with the short linker also exhibited increased thermal stability and exopeptidase resistance. Moreover, induction of the target proteins in an oxygen-deficient culture rendered fluorescent E. coli BL21 (DE3) cells brighter than those overexpressing the linear construct. Thus, the cyclic reporter can hopefully be used in certain thermophilic anaerobes.

IMMUNE PATTERN OF THE SEX-ROLE REVERSED SEAHORSE Hippocampus erectus, A SUPPLEMENT FOR BATEMAN’S PRINCIPLE

Tingting Lin,Dong Zhang,YinFeng Xi,Xin Liu 한국수산과학회 양식분과 2015 한국수산과학회 양식분과 학술대회 Vol.2015 No.5

Metathetic Degradation of Styrene-Butadiene Rubber via Ru-Alkylidene Complex Catalyzed Reaction

Tingting Zou,Bin Jiang,Shaohui Lin,Qinmin Pan 한국고분자학회 2016 폴리머 Vol.40 No.5

Metathetic degradation and functionalization of styrene-butadiene rubber (SBR) were performed with allyl hexanoate, allyl chloroacetate, 5-hexenyl acetate and trifluoroethyl methacrylate as chain transfer agents (CTAs) using Grubbs 2<SUP>nd</SUP> generation catalyst. It has been demonstrated that the catalyst concentration, CTA concentration and reaction time were major factors influencing the molecular weights and polydispersity indices of targeted telechelic SBR oligomers. Well-defined oligomers with molecular weights ranging from 700 to 36600 g mol<SUP>-1</SUP> and polydispersity indices ranging from 1.17 to 4.79 were realized. The structures of the SBR oligomers were determined by FTIR and <SUP>1</SUP>H NMR analyses, which indicated that the functional groups of the CTAs were successfully attached onto the end of the polymer chains. To further investigate the performance of SBR oligomers, differential scanning calorimetry (DSC) analysis was performed, which indicated that the glass transition temperature (Tg) of the metathesis products decreased with longer reaction time.

Supplementing Vitamin E to the Ration of Beef Cattle Increased the Utilization Efficiency of Dietary Nitrogen

Wei, Chen,Lin, Shixin,Wu, Jinlong,Zhao, Guangyong,Zhang, Tingting,Zheng, Wensi Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.3

The objectives of the trial were to investigate the effects of supplementing vitamin E (VE) on nutrient digestion, nitrogen (N) retention and plasma parameters of beef cattle in feedlot. Four growing Simmental bulls, fed with a total mixed ration composed of corn silage and concentrate mixture as basal ration, were used as the experimental animals. Four levels of VE product, i.e. 0, 150, 300, 600 mg/head/d (equivalent to 0, 75, 150, 300 IU VE/head/d), were supplemented to the basal ration (VE content 38 IU/kg dry matter) in a $4{\times}4$ Latin square design as experimental treatments I, II, III and IV, respectively. Each experimental period lasted 15 days, of which the first 12 days were for pretreatment and the last 3 days for sampling. The results showed that supplementing VE did not affect the nutrient digestibility (p>0.05) whereas decreased the urinary N excretion (p<0.01), increased the N retention (p<0.05) and tended to increase the microbial N supply estimated based on the total urinary purine derivatives (p = 0.057). Supplementing VE increased the plasma concentrations of VE, glucose and triglycerol (TG) (p<0.05) and tended to increase the plasma concentration of total protein (p = 0.096) whereas did not affect the plasma antioxidant indices and other parameters (p>0.05). It was concluded that supplementing VE up to 300 IU/head/d did not affect the nutrient digestibility whereas supplementing VE at 150 or 300 IU/head/d increased the N retention and the plasma concentrations of VE and TG (p<0.05) of beef cattle.

Specific Alternation of Gut Microbiota and the Role of Ruminococcus gnavus in the Development of Diabetic Nephropathy

( Jinni Hong ),( Tingting Fu ),( Weizhen Liu ),( Yu Du ),( Junmin Bu ),( Guojian Wei ),( Miao Yu ),( Yanshan Lin ),( Cunyun Min ),( Datao Lin ) 한국미생물생명공학회 2024 Journal of microbiology and biotechnology Vol.34 No.3

In this study, we aim to investigate the precise alterations in the gut microbiota during the onset and advancement of diabetic nephropathy (DN) and examine the impact of Ruminococcus gnavus (R. gnavus) on DN. Eight-week-old male KK-Ay mice were administered antibiotic cocktails for a duration of two weeks, followed by oral administration of R. gnavus for an additional eight weeks. Our study revealed significant changes in the gut microbiota during both the initiation and progression of DN. Specifically, we observed a notable increase in the abundance of Clostridia at the class level, higher levels of Lachnospirales and Oscillospirales at the order level, and a marked decrease in Clostridia_UCG-014 in DN group. Additionally, there was a significant increase in the abundance of Lachnospiraceae, Oscillospiraceae, and Ruminococcaceae at the family level. Moreover, oral administration of R. gnavus effectively aggravated kidney pathology in DN mice, accompanied by elevated levels of urea nitrogen (UN), creatinine (Cr), and urine protein. Furthermore, R. gnavus administration resulted in down-regulation of tight junction proteins such as Claudin-1, Occludin, and ZO-1, as well as increased levels of uremic toxins in urine and serum samples. Additionally, our study demonstrated that orally administered R. gnavus up-regulated the expression of inflammatory factors, including nucleotide-binding oligomerization domain-like receptor pyrin domain-containing protein 3 (NLRP3) and Interleukin (IL)-6. These changes indicated the involvement of the gut-kidney axis in DN, and R. gnavus may worsen diabetic nephropathy by affecting uremic toxin levels and promoting inflammation in DN.

Association of MMP-9 C-1562T polymorphism with risk of Henoch-Schönlein purpura nephritis in children of southeast China

Jinwen Xu,Liping Zhao,Hongxia Zhou,Tingting Ge,Lin Zhang 한국유전학회 2017 Genes & Genomics Vol.39 No.4

Henoch-Schönlein purpura nephritis (HSPN) is the most prevalent vasculitis in childhood worldwide. Although the etiology of HSPN is not yet fully elucidated, it is believed to be closely related with infections and genetic predispositions. In this study, a cohort of children from southeast China, including 108 healthy controls and 184 patients were involved in. We scanned the promoter region and the whole gene for genetic variations. A C/T transition located in the promoter region of MMP-9 gene, C-1562T was identified. Subjects were genotyped by using SNaPshot sequencing and the frequencies of CC, CT and TT genotypes were 43, 33 and 24% in patients and 53, 37 and 10% in healthy controls. Allele distribution was found to be in Hardy–Weinberg equilibrium (P = 0.17). Association analysis revealed that the polymorphism was significantly related with HSPN risk (P < 0.05) and T allele was shown to be a risk factor (P = 0.003, odds ratio (OR) 1.63, 95% confidence interval (CI) 1.13–2.34). Additionally, we measured the serum MMP-9 concentration and quantified the mRNA expression. Results showed that an elevated protein level was observed in patients compared with controls in both ELISA (P = 0.0029, 136.5 μg/L vs. 103.9 μg/L) and Western blot assays. Furthermore, we also detected 1.93-fold increase in the mRNA transcription in patients carrying homozygous TT genotype, indicating enhanced promoter activity caused by the polymorphism. Based on the incidence risk, a cut-off value of serum MMP-9 served as HSPN diagnosis was suggested at 155 μg/L. Conclusively, our findings suggested that MMP-9 polymorphism was significantly associated with HSPN susceptibility, and C-1562T T allele contributed to HSPN development.

Experimental Study on the Monotonic and Cyclic Behavior of Carbonate Sand in the South China Sea

Xin Liu,Sa Li,Lan Lin,Tingting Li,Jiangsong Yin 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.9

Carbonate soils have specific properties that differ from those of siliceous sand. The monotonic and cyclic behavior of carbonate sand from Jinqing Island in the South China Sea was examined by undrained monotonic and cyclic simple shear tests in this paper. The monotonic test results show that the phase transformation state friction angle is 25.7o, and the critical state friction angle decreases from 38.7o to 37.3o due to particle crushing. By comparing the experimental data from the monotonic and cyclic tests, we found that the trend of the peak shear stress ratio with shear strain in each cycle of cyclic tests was close to that of monotonic tests. If the cyclic stress ratio of symmetrical cyclic tests is normalized with the phase transformation strengths obtained by the corresponding monotonic tests, it has a good relationship with the number of cycles at failure and is not affected by the relative density and vertical consolidation stress. The effects of the relative density, vertical consolidation stress and initial static shear stress on the undrained cyclic strength are discussed. Finally, a comparison of the undrained cyclic strength of carbonate sand from different regions shows that different carbonate sands have almost identical undrained cyclic strength under the medium dense state, but significant quantitative differences are observed between these carbonate sands under the dense state.

Kinetics and Modeling for Extraction of Chrysin from Oroxylum indicum Seeds

Li Zhou,Ting Jing,Peipei Zhang,Liqin Zhang,Shaona Cai,Tingting Liu,Huihui Fan,Guangde Yang,Rong Lin,Jiye Zhang 한국식품과학회 2015 Food Science and Biotechnology Vol.24 No.6

Research on extraction of chrysin is crucial for theoretical purposes and for food industrial bioprocesses. Optimization and kinetics of chrysin extraction from seeds of Oroxylum indicum (L.) Vent. were analyzed using agitated solid-liquid extractions with ethanol and water mixtures. The influence of extraction process parameters was investigated. Optimized conditions for chrysin extraction were a 0.2 mole fraction of ethanol as an extraction solvent, a temperature of 318 K, an agitation speed 1,400 rpm, and a solid to solvent ratio of 1:30. The extraction kinetic behavior of chrysin followed first order kinetics. The kinetic expression developed by Spiro and Siddique was used and the model was in agreement with experimental results. The diffusion coefficient ranged from 1.38×10−11 to 19.43×10−11 m2·s−1 and the activation energy for extraction kinetics was 21.85 kJ·mol−1.

Dual-Responsive Cross-Linked Micelles from Amphiphilic Four-Arm Star Copolymers with Different Block Ratios for Triggering DOX Release

Yunwei Huang,Yanzhe Li,Zilun Tang,Qiuping Su,Tingting Liao,Yuxin Gu,Xiaofeng Lin,Xihong Zu,Wenjing Lin,Guobin Yi 한국고분자학회 2020 Macromolecular Research Vol.28 No.8

The four-arm star copolymers poly(methacrylic acid)-poly(2-hydroxyethyl methacrylate-disulfide~)-poly(poly(ethylene glycol) methyl ether methacrylate) (4AS-PMAAx-(PHEMA-SS~)y-PPEGMAz) with four different block ratios were synthesized and could self-assembled into cross-linked polymer micelles for the exploration of the structure-property relationship. The cross-linked polymer micelles in aqueous solution had low critical micelle concentration (CMC) values (1.9-4.6 mg/L), which exhibited better stability than non-cross-linked micelles. The CMC value decreased with the increase of the length of inner PMAA core and hydrophobic PHEMA cross-linked middle layer. The blank and doxorubicin (DOX)- loaded micelles with different block ratios were prepared by dialysis with the particle sizes of 120-240 nm. The longer inner PMAA core and cross-linked middle layer enhanced the drug loading content (DLC) results and led to relatively bigger particle sizes of polymer micelles. The in vitro DOX release data revealed that DOX-loaded micelles had low DOX cumulative release percentages of 18-37% after 110 h at pH 7.4, but up to 83-90% when introducing reductant GSH at pH 5.0. The 4AS-PMAA21.2-(PHEMASS~) 13.1-PPEGMA5.1 micelles with the longest PMAA core had the largest cumulative release of 90.1%. The DOX release process and mechanism of the micelles at different conditions fitted well with the semi-empirical equation. Overall, the results demonstrated that the block ratios and pH/redox-responsiveness of these four-arm star copolymers could be well-controlled and their self-assembled cross-linked micelles as anticancer drug carrier system could be improved by optimizing the different ratios.

Ganoderic acid A attenuates high‑fat‑diet‑induced liver injury in rats by regulating the lipid oxidation and liver inflammation

Fuli Liu,Kejian Shi,Jiaojiao Dong,Zhousheng Jin,Yiquan Wu,Yaoyao Cai,Tingting Lin,Qianqian Cai,Le Liu,Yujian Zhang 대한약학회 2020 Archives of Pharmacal Research Vol.43 No.7

Ganoderic Acid A (GA) has many pharmacologicaleffects such as anti-tumor, antibacterial, anti-inflammatory,and immunosuppressive effects. However, the protectiveeffect of GA on liver injury has not been reported. Thisstudy aimed to investigate the action of GA on insufficientmethionine and choline combined with high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD) in rats. NAFLD model was established by insufficient methionineand choline combined with high fat feeding to rats. The levelsof Acetyl-CoA carboxylase, fatty acid synthase, sterolregulatory element binding protein, liver X receptors, AMPactivatedprotein kinase, peroxisome proliferator-activatedreceptor α, PPARg coactivator 1α and NF-κB pathway inthe liver were detected by western blot. The results of thisstudy demonstrated that the expression of GA can not onlysignificantly decrease the live weight and liver weight perbody weight of HFD mice, but also restore the alanine aminotransferase,aspartate aminotransferase, total bilirubinlevels, triglyceride and cholesterol in serum. In addition,the expression of GA increased the levels of high-densitylipoprotein cholesterol in serum, ameliorated pathologicalchanges and decreased NAS score of mice’s liver. In conclusion,the treatment with GA could improve NAFLD in ratsby regulating the levels of signaling events involved in freefatty acid production, lipid oxidation and liver inflammation.