Improvement of ATP regeneration efficiency and operation stability in porcine interferon-α production by Pichia pastoris under lower induction temperature

Minjie Gao,Zhongping Shi,Shijuan Dong,Ruisong Yu,Jianrong Wu,Zhiyong Zheng,Xiaobei Zhan 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.6

The performance of traditional heterologous protein production by Pichia pastoris with methanol induction at 30 ℃ is poor, characterized by low ATP regeneration rate and weak operation stability. A low temperature induction strategy at 20 ℃ was thus adopted for efficient porcine interferon-α production in a 10 L fermentor. With the strategy,maximal methanol tolerance level could reach about 40 g/L to effectively deal with methanol concentration variations,so that the complicated on-line methanol measurement system could be eliminated. Moreover, metabolic analysis based on multiple state-variables measurements indicated that pIFN-α antiviral activity enhancement profited from the formation of an efficient ATP regeneration system at 20℃ induction. Compared to the induction strategy at 30 ℃, the proposed strategy increased the ATP regeneration rate by 49-66%, the maximal p_IFN-α antiviral activity was enhanced about 20-fold and reached a higher level of 1.5×10^6 IU/mL.

Graphene Quantum Dots Enhanced Photocatalytic Activity of Sb2WO6 Under Ultraviolet- and Visible-Light Irradiation

Shan Li,Zhongping Chen,Datong Wu,Yong Qin,Yong Kong 대한화학회 2020 Bulletin of the Korean Chemical Society Vol.41 No.5

A novel composite of graphene quantum dots functionalized Sb2WO6 (GQDs/Sb2WO6) was prepared by an electrostatic self-assembly method and used as a photocatalyst for the degradation of an organic pollutant. The resulting GQDs/Sb2WO6 was characterized by electron microscopy and optical measurements. The photocatalytic activity of GQDs/Sb2WO6 was investigated by degrading methyl orange (MO) under UV-light and visible-light irradiation. Compared with pure Sb2WO6, enhancement of the photocatalytic performance of GQDs/Sb2WO6 was achieved, and the degradation efficiency for MO was almost 100% within 3 h under UV-light irradiation and 71.4% within 3 h under visible-light irradiation. The photocatalytic degradation mechanism of GQDs/Sb2WO6 was illustrated by free radical and hole scavenging experiments, and the main active species were confirmed to be holes (h+) and superoxide anion radicals (O2·?). Moreover, the GQDs/Sb2WO6 composites exhibited high recyclability and stability and had potential application for decomposing other organic contaminants in water.

Identification of copy number variations using high density whole-genome single nucleotide polymorphism markers in Chinese Dongxiang spotted pigs

Chengbin Wang,Hao Chen,Xiaopeng Wang,Zhongping Wu,Weiwei Liu,Yuanmei Guo,Jun Ren,Nengshui Ding 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.12

Objective: Copy number variations (CNVs) are a major source of genetic diversity complementary to single nucleotide polymorphism (SNP) in animals. The aim of the study was to perform a comprehensive genomic analysis of CNVs based on high density whole-genome SNP markers in Chinese Dongxiang spotted pigs. Methods: We used customized Affymetrix Axiom Pig1.4M array plates containing 1.4 million SNPs and the PennCNV algorithm to identify porcine CNVs on autosomes in Chinese Dongxiang spotted pigs. Then, the next generation sequence data was used to confirm the detected CNVs. Next, functional analysis was performed for gene contents in copy number variation regions (CNVRs). In addition, we compared the identified CNVRs with those reported ones and quantitative trait loci (QTL) in the pig QTL database. Results: We identified 871 putative CNVs belonging to 2,221 CNVRs on 17 autosomes. We further discarded CNVRs that were detected only in one individual, leaving us 166 CNVRs in total. The 166 CNVRs ranged from 2.89 kb to 617.53 kb with a mean value of 93.65 kb and a genome coverage of 15.55 Mb, corresponding to 0.58% of the pig genome. A total of 119 (71.69%) of the identified CNVRs were confirmed by next generation sequence data. Moreover, functional annotation showed that these CNVRs are involved in a variety of molecular functions. More than half (56.63%) of the CNVRs (n = 94) have been reported in previous studies, while 72 CNVRs are reported for the first time. In addition, 162 (97.59%) CNVRs were found to overlap with 2,765 previously reported QTLs affecting 378 phenotypic traits. Conclusion: The findings improve the catalog of pig CNVs and provide insights and novel molecular markers for further genetic analyses of Chinese indigenous pigs.

Effect of additives on structure and corrosion resistance of ceramic coatings on Mg–Li alloy by micro-arc oxidation

Shi Lingling,Xu Yongjun,Li Kang,Yao Zhongping,Wu Songquan 한국물리학회 2010 Current Applied Physics Vol.10 No.3

In order to improve the corrosion resistance of ceramic coatings formed on Mg–5mass%Li substrate by micro-arc oxidation (MAO) method, two kinds of additives (Na2B4O7 and EDTA) were doped in Na2SiO3–Na3PO4 solution system. The surface and cross-section morphology feature, phase composition and elemental composition were examined by SEM, XRD and EDX, respectively. Corrosion resistance of ceramic coating was tested by electrochemical methods. It was revealed that all coatings were composed of MgO and Mg2SiO4, and had porous surface structure. Doping of additives had little effect on the elemental composition, while it influenced the morphological feature of the coating. The results of electrochemical tests showed that the coatings prepared in the solutions with additive had good corrosion resistance. The addition of EDTA to the solution made coatings thinner and more uniform which resulted in better general corrosion resistance. The addition of Na2B4O7 to the solution made coatings much thicker and compacter, which improved the pitting corrosion resistance.

AQUEOUS SYNTHESIS OF HIGH QUANTUM YIELD AND MONODISPERSED THIOL-CAPPED CdxZn1-xTe QUANTUM DOTS BASED ON ELECTROCHEMICAL METHOD

JUNWEI LI,YANG JIANG,YUGANG ZHANG,DI WU,ANQI LUO,ZHONGPING ZHANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2012 NANO Vol.7 No.2

A facile green approach has been developed to control the growth regime in the aqueous synthesis of CdxZn1-xTe semiconductor quantum dots (QDs) based on the electrochemistry method. The Low growth temperature and slow injection of Te precursor are used to prolong the diffusion controlled stage and thus suppress Ostwald ripening during the nanocrystal growth. The experimental results showed that a low concentration of Te precursor will definitely influence the growth procedure. The UV–visible absorption spectra, as well as transmission electron microscopy (TEM) shows the QDs a good monodispersity at any interval of the reaction procedure. The high-resolution transmission electron microscopy (HRTEM) images and powder X-ray diffraction (XRD) pattern suggested that the as-prepared QDs have high crystallinity and cubic structure. The size and composition-dependent fluorescent emission wavelength of the resultant CdxZn1-xTe alloyed QDs can be tuned from 460 to 610 nm, and their photoluminescent quantum yield can reach up to 70%. Especially in the wavelength range of 510–578 nm, the overall PL QYs of the as-prepared CdxZn1-xTe QDs were above 50%. The current work suggests that electrochemical method is an attractive approach to the synthesis of high-quality II-VI ternary alloyed semiconductor QDs at large-scale with a prominent cost advantage.

MicroRNA-1 in Cardiac Diseases and Cancers

Li, Jianzhe,Dong, Xiaomin,Wang, Zhongping,Wu, Jianhua The Korean Society of Pharmacology 2014 The Korean Journal of Physiology & Pharmacology Vol.18 No.5

MicroRNAs (miRs) are endogenous ${\approx}22$-nt non-coding RNAs that participate in the regulation of gene expression at post-transcriptional level. MiR-1 is one of the muscle-specific miRs, aberrant expression of miR-1 plays important roles in many physiological and pathological processes. In this review, we focus on the recent studies about miR-1 in cardiac diseases and cancers. The findings indicate that miR-1 may be a novel, important biomarker, and a potential therapeutic target in cardiac diseases and cancers.

Effect of Metabolic Structures and EnergyRequirements on Curdlan Production byAlcaligenes faecalis

Xiao Bei Zhan,Zhi-Yong Zheng,Jin Woo Lee,Zhongping Shi,Lei Wang,Li Zhu,Jian-Rong Wu,Chi Chung Lin 한국생물공학회 2007 Biotechnology and Bioprocess Engineering Vol.12 No.4

A comprehensive metabolic network was proposed for Alcaligenes faecalis and employed in a stoichiometrically based flux balance model for curdlan production optimization. The maximal yield of curdlan was evaluated for curdlan batch production. Various metabolic structures and metabolic pathway distributions related with the curdlan maximal yield was evaluated. The results showed that the energy efficiency rather than the substrate supply was the major constraint for the enhancement of curdlan production. The increase in specific rate of glucose uptake could enhance curdlan production yield due to the decrease of the ratio of metabolic maintenance to substrate consumption. However, some of the energy loss and nutrient limitation associated with the increase of metabolic maintenance would adversely affect the conversion efficiency of the substrate.

Effect of Metabolic Structures and Energy Requirements on Curdlan Production by Alcaligenes faecalis

Zheng, Zhi-Yong,Lee, Jin-Woo,Zhan, Xiao Bei,Shi, Zhongping,Wang, Lei,Zhu, Li,Wu, Jian-Rong,Lin, Chi Chung Korean Society for Biotechnology and Bioengineerin 2007 Biotechnology and Bioprocess Engineering Vol.12 No.4

A comprehensive metabolic network was proposed for Alcaligenes faecalis and employed in a stoichiometrically based flux balance model for curdlan production optimization. The maximal yield of curdlan was evaluated for curdlan batch production. Various metabolic structures and metabolic pathway distributions related with the curdlan maximal yield was evaluated. The results showed that the energy efficiency rather than the substrate supply was the major constraint for the enhancement of curdlan production. The increase in specific rate of glucose uptake could enhance curdlan production yield due to the decrease of the ratio of metabolic maintenance to substrate consumption. However, some of the energy loss and nutrient limitation associated with the increase of metabolic maintenance would adversely affect the conversion efficiency of the substrate.