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Wang Sha,Yuan Anjie,Zeng Liping,Hou Sikai,Wang Meng,Li Lei,Cai Zhendong,Zhong Guowei 한국미생물학회 2021 The journal of microbiology Vol.59 No.1
Aspergillus fumigatus is a well-known opportunistic pathogen that causes invasive aspergillosis (IA) infections with high mortality in immunosuppressed individuals. Morphogenesis, including hyphal growth, conidiation, and cell wall biosynthesis is crucial in A. fumigatus pathogenesis. Based on a previous random insertional mutagenesis library, we identified the putative polysaccharide synthase gene Afcps1 and its paralog Afcps2. Homologs of the cps gene are commonly found in the genomes of most fungal and some bacterial pathogens. Afcps1/cpsA is important in sporulation, cell wall composition, and virulence. However, the precise regulation patterns of cell wall integrity by Afcps1/cpsA and further effects on the immune response are poorly understood. Specifically, our in-depth study revealed that Afcps1 affects cell-wall stability, showing an increased resistance of ΔAfcps1 to the chitinmicrofibril destabilizing compound calcofluor white (CFW) and susceptibility of ΔAfcps1 to the β-(1,3)-glucan synthase inhibitor echinocandin caspofungin (CS). Additionally, deletion of Afcps2 had a normal sporulation phenotype but caused hypersensitivity to Na+ stress, CFW, and Congo red (CR). Specifically, quantitative analysis of cell wall composition using high-performance anion exchange chromatography- pulsed amperometric detector (HPAEC-PAD) analysis revealed that depletion of Afcps1 reduced cell wall glucan and chitin contents, which was consistent with the downregulation of expression of the corresponding biosynthesis genes. Moreover, an elevated immune response stimulated by conidia of the ΔAfcps1 mutant in marrow-derived macrophages (BMMs) during phagocytosis was observed. Thus, our study provided new insights into the function of polysaccharide synthase Cps1, which is necessary for the maintenance of cell wall stability and the adaptation of conidia to the immune response of macrophages in A. fumigatus.
Liu Sha,Cai Yi-xi,Fan Yong-sheng,Li Xiao-hua,Wang Jia-jun 대한환경공학회 2017 Environmental Engineering Research Vol.22 No.1
Direct catalysis of vapors from vacuum pyrolysis of biomass was performed on MCM-41 to investigate the effects of operating parameters including catalyzing temperature, catalyzing bed height and system pressure on the organic yields. Optimization of organic phase yield was further conducted by employing response surface methodology. The statistical analysis showed that operating parameters have significant effects on the organic phase yield. The organic phase yield first increases and then decreases as catalyzing temperature and catalyzing bed height increase, and decreases as system pressure increases. The optimal conditions for the maximum organic phase yield were obtained at catalyzing temperature of 502.7℃, catalyzing bed height of 2.74 cm and system pressure of 6.83 kPa, the organic phase yield amounts to 15.84% which is quite close to the predicted value 16.19%. The H/C, O/C molar ratios (dry basis), density, pH value, kinematic viscosity and high heat value of the organic phase obtained at optimal conditions were 1.287, 0.174, 0.98 g/cm3, 5.12, 5.87 mm2/s and 33.08 MJ/kg, respectively. Organic product compositions were examined using gas chromatography/mass spectrometry and the analysis showed that the content of oxygenated aromatics in organic phase had decreased and hydrocarbons had increased, and the hydrocarbons in organic phase were mainly aliphatic hydrocarbons. Besides, thermo-gravimetric analysis of the MCM-41 zeolite was conducted within air atmosphere and the results showed that when the catalyst continuously works over 100 min, the index of physicochemical properties of bio-oil decreases gradually from 1.15 to 0.45, suggesting that the refined bio-oil significantly deteriorates. Meanwhile, the coke deposition of catalyst increases from 4.97% to 14.81%, which suggests that the catalytic activity significantly decreases till the catalyst completely looses its activity.
Three New 29 Carbon Skeletons Pentacyclic Triterpenoids and S-equol from Biogas Slurry
Jian-Feng Xu,Hui-Bin Wu,Ding-Cai Liu,Long Sha,Wen-Hui Wu,Hua Fan,Yishan Song,Hong-Guang Zhu 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.12
Bioactive natural products were firstly obtained from biogas slurry. Three new 29 carbon skeletons of the pentacyclic triterpenoid compounds 24-norolean-12-ene-3,22-dione (1), 3β-hydroxy-24-norolean-12-ene-22-one (2), 3α-hydroxy-24-norolean-12-ene-22-one (3), as well as one known compound S-equol (4) were isolated and purified from the MeOH extract of chicken manure biogas slurry. The molecular structures of the four compounds were elucidated based on the extensive spectroscopic data analysis, and the structure of Compound 1 was further confirmed by single-crystal X-ray diffraction. The structures of Compounds 1, 2, and 3 are similar with oleanolicum and hederagenin that has excellent anti-tumor activities. The cytotoxicity against five cancer cell lines (Hela, A549, MCF7, PC3, and B16) of Compounds 1–4 was tested. Similar to Compound 4 (S-equol), Compounds 1–3 (pentacyclic triterpenoids) showed cytotoxicity activity against different tumor cell lines. Compounds 1–3 showed slightly lower cytotoxicity activities than Compound 4. The IC50 of Compound 4 was determined to be 9.7–27.6 μM, while the IC50 values of 1–3 were 17.6–65.3 μM. There are no significant differences in the cytotoxicity capacities between Compounds 1, 2, and 3.
( Xiao Zhao ),( Ya-juan Cui ),( Sha-sha Bai ),( Zhi-jie Yang ),( Miao-cai ),( Sarah Megrous ),( Tariq Aziz ),( Abid Sarwar ),( Dong Li ),( Zhen-nai Yang ) 한국미생물 · 생명공학회 2021 Journal of microbiology and biotechnology Vol.31 No.8
Casein-derived antioxidant peptides by using microbial proteases have gained increasing attention. Combination of two microbial proteases, Protin SD-NY10 and Protease A “Amano” 2SD, was employed to hydrolyze casein to obtain potential antioxidant peptides that were identified by LC-MS/MS, chemically synthesized and characterized in a oxidatively damaged HepG2 cell model. Four peptides, YQLD, FSDIPNPIGSEN, FSDIPNPIGSE, YFYP were found to possess high 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability. Evaluation with HepG2 cells showed that the 4 peptides at low concentrations (< 1.0 mg/ml) protected the cells against oxidative damage. The 4 peptides exhibited different levels of antioxidant activity by stimulating mRNA and protein expression of the antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), as well as nuclear factor erythroid-2-related factor 2 (Nrf2), but decreasing the mRNA expression of Kelch-like ECH-associated protein 1 (Keap1). Furthermore, these peptides decreased production of reactive oxygen species (ROS) and malondialdehyde (MDA), but increased glutathione (GSH) production in HepG2 cells. Therefore, the 4 casein-derived peptides obtained by using microbial proteases exhibited different antioxidant activity by activating the Keap1-Nrf2 signaling pathway, and they could serve as potential antioxidant agents in functional foods or pharmaceutic preparation.
Dan Zhang,Zongqi Xu,Hong Xu,Xiaohai Feng,Sha Li,Heng Cai,Yan Wei,Pingkai Ouyang 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.6
In this study, the production of poly(γ-glutamic acid) by Bacillus subtilis NX-2 (PGA) at different agitation speeds was investigated. Based on the analysis of specific cell growth rate (μ) and specific PGA formation rate (q_p),a two-stage strategy for agitation speed control was proposed. During the first 24 h, an agitation speed of 600rpm was used to maintain a high μ for better cell growth,which then reduced to 400 rpm after 24 h to maintain a high qp to enhance PGA production. Using this method, the maximum concentration of PGA reached 40.5 ± 0.91 g/L and the PGA productivity was 0.56 ± 0.012 g/L/h, which was 17.7 and 9.8% higher, respectively, than the best results obtained when a constant agitation speed was used. The flux distributions and the related enzymes of 2-oxoglutarate could be affected by this two-stage strategy for agitation speed. The activity of isocitrate dehydrogenase and glutamate dehydrogenase at the key node of 2-oxoglutarate increased, and more flux distribution was directed to glutamate. The flux distribution from extracellular to intracellular glutamate also increased and improved PGA production as the glutamate uptake rates increased using the agitation-shift control method.
Shang, Jiang-Hua,Xu, Ru-Xiang,Jiang, Xiao-Dan,Zou, Yu-Xi,Qin, Ling-Sha,Cai, Ying-Qian,Yang, Zhi-Jun,Zheng, Xing,Cui, Sheng Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.9
The aim of this study was to evaluate if oocytes, aspirated from postovulatory ovarian follicles of superovulated rabbits 14 h post-hCG administration, could be efficiently used as ooplasm recipients for somatic cell nuclear transfer (SCNT). Within a common SCNT protocol, a comparison between oocytes recovered by direct aspiration (aspirated) from available ovarian follicles and oocytes flushed out from oviducts (flushed) was carried out. The results showed that maturation and enucleation rates of aspirated oocytes were 70.7% and 69.2%, significantly lower than 95.3% (p<0.01) and 83.6% (p<0.05), respectively, from flushed oocytes. However, following enucleation of matured oocytes as ooplasm recipients for SCNT, no difference was recorded in fusion and cleavage rates, as well as blastocyst development from cleaved embryos or hatching of blastocysts between aspirated and flushed groups. Additionally, some matured aspirated and flushed oocytes were also used for immediate parthenogenetic activation and the resulting embryo development was not significantly different. Results from this study show the following: i) the majority of oocytes aspirated from postovulatory ovarian follicles of superovulated rabbits 14 h post-hCG administration are matured and can be used directly as ooplasm recipients for SCNT; ii) the reconstructed embryos derived from these oocytes have similar in vitro developmental ability to those flushed from the oviducts.