A new terpene coumarin microbial transformed by Mucor polymorphosporus induces apoptosis of human gastric cancer cell line MGC-803

Guangzhi Li,Junchi Wang,Xiaojin Li,Jianguo Xu,Zhao Zhang,Jianyong Si 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.6

20-Z auraptene (1) is a synthesized monoterpenecoumarin with anticancer activity against human gastriccancer cells. In order to find new potential anticancer agent,Mucor polymorphosporus was used to transform cis-auraptene. Four new terpene coumarins with notable changesin the skeletal backbone, 20-Z auraptene A-D (2–5), wereobtained and evaluated for their antiproliferative effectsagainst human normal gastric epithelium cells and humangastric cancer cells. These new compounds showed selectivecytotoxic activity against MGC-803 cells with IC50values from 0.78 ± 0.13 to 10.78 ± 1.83 lM and thetherapeutic index could also be significantly improved(TI = 59.0) compared with that of 1 (TI = 5.5). Thestructures of these metabolites were elucidated throughextensive spectroscopic methods, and the possible biotransformationpathway of 1 by Mucor polymorphosporuswas also proposed. Furthermore, the mechanism of theantiproliferative effects against MGC-803 cells of the mostpotent compound, 20-Z auraptene A (2), was characterized. Annexin V/PI staining and abnormal expression of apoptosis-related protein suggested that compound 2 inducesapoptosis in gastric cancer MGC-803 cells. Therefore, it ispossible that compound 2 has the potential to be applied ingastric cancer therapy.

Characteristic and role of chromosomal type II toxin-antitoxin systems locus in Enterococcus faecalis ATCC29212

Li Zhen,Shi Chao,Gao Shanjun,Zhang Xiulei,Lu Di,Liu Guangzhi 한국미생물학회 2020 The journal of microbiology Vol.58 No.12

The Gram-positive bacterium Enterococcus faecalis is currently one of the major pathogens of nosocomial infections. The lifestyle of E. faecalis relies primarily on its remarkable capacity to face and survive in harsh environmental conditions. Toxin-antitoxin (TA) systems have been linked to the growth control of bacteria in response to adverse environments but have rarely been reported in Enterococcus. Three functional type II TA systems were identified among the 10 putative TA systems encoded by E. faecalis ATCC29212. These toxin genes have conserved domains homologous to MazF (DR75_ 1948) and ImmA/IrrE family metallo-endopeptidases (DR75_ 1673 and DR75_2160). Overexpression of toxin genes could inhibit the growth of Escherichia coli. However, the toxin DR75_1673 could not inhibit bacterial growth, and the bacteriostatic effect occurred only when it was coexpressed with the antitoxin DR75_1672. DR75_1948–DR75_1949 and DR75_ 160–DR75_2161 could maintain the stable inheritance of the unstable plasmid pLMO12102 in E. coli. Moreover, the transcription levels of these TAs showed significant differences when cultivated under normal conditions and with different temperatures, antibiotics, anaerobic agents and H2O2. When DR75_2161 was knocked out, the growth of the mutant strain at high temperature and oxidative stress was limited. The experimental characterization of these TAs loci might be helpful to investigate the key roles of type II TA systems in the physiology and environmental stress responses of Enterococcus.

Chemical constituents from the fruiting bodies of Cryptoporus volvatus

Junchi Wang,Guangzhi Li,Na Lv,Li Gao,Liangang Shen,Jianyong Si 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.6

New drimane-type sesquiterpene cryptoporol A(1), cryptoporic acid derivative 60-cryptoporic acid E methylester (2), and pseudouridine derivative cryptoporineA(3), aswell as a known ergosterol 5a,8a-epidioxy-22E-ergosta-6,22-dien-3b-ol (4), were isolated from a 90 % alcoholextract of the fruiting bodies of Cryptoporus volvatus. Thestructures of these compounds were established by spectroscopicanalysis and circular dichroism. 5a,8a-epidioxy-22Eergosta-6,22-dien-3b-ol (4) exhibited antiviral activityagainst porcine reproductive and respiratory syndrome virus,and all compounds showed weak antioxidant activities.

Polysulfide/Graphene Nanocomposite Film for Simultaneous Electrochemical Determination of Cadmium and Lead Ions

Ruyuan Jiang,Niantao Liu,Yuhong Su,Sanshuang Gao,Xamxikamar Mamat,Thomas Wågberg,Yongtao Li,Xun Hu,Guangzhi Hu 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.08

An integrative electroanalytical method was developed for detecting Cd2+ and Pb2+ ions in aqueous solutions. Polysulfide/graphene (RGO-S) nanocomposites were prepared and their performance as electrochemical sensors for Cd2+ and Pb2+ was evaluated. The RGO-S nanocomposite was carefully characterized by scanning electron microscopy with energy-dispersive X-ray spectrometry, transmission electron microscopy, and X-ray photoelectron spectroscopy. The as-prepared RGO-S was incorporated into a pyrolytic graphite electrode (RGO-S/PGE) and used for detecting trace amount of Cd2+ and Pb2+ by differential pulse anodic stripping voltammetry. Under optimal conditions, the stripping peak current of RGO-S/PGE varies linearly with heavy metal ion concentration in the ranges 2.0–300 μg L -1 for Cd2+ and 1.0–300 μg L -1 for Pb2+. The limits of detection for Cd2+ and Pb2+ were estimated to be about 0.67 μg L -1 and 0.17 μg L -1, respectively. The prepared electrochemical heavy-metal-detecting electrode provides good repeatability and reproducibility with high sensitivity, making it a suitable candidate for monitoring Cd2+ and Pb2+ concentrations in aqueous environmental samples.

Protective efficacy of a high-growth reassortant swine H3N2 inactivated vaccine constructed by reverse genetic manipulation

Feng Wen,Ji-Hong Ma,Hai Yu,Fu-Ru Yang,Meng Huang,Yan-Jun Zhou,Ze-Jun Li,Guangzhi Tong 대한수의학회 2014 Journal of Veterinary Science Vol.15 No.3

Novel reassortant H3N2 swine influenza viruses (SwIV)with the matrix gene from the 2009 H1N1 pandemic virushave been isolated in many countries as well as duringoutbreaks in multiple states in the United States, indicatingthat H3N2 SwIV might be a potential threat to public health. Since southern China is the world’s largest producer of pigs,efficient vaccines should be developed to prevent pigs fromacquiring H3N2 subtype SwIV infections, and thus limit thepossibility of SwIV infection at agricultural fairs. In thisstudy, a high-growth reassortant virus (GD/PR8) wasgenerated by plasmid-based reverse genetics and tested as acandidate inactivated vaccine. The protective efficacy of thisvaccine was evaluated in mice by challenging them withanother H3N2 SwIV isolate [A/Swine/Heilongjiang/1/05(H3N2) (HLJ/05)]. Prime and booster inoculation withGD/PR8 vaccine yielded high-titer serum hemagglutinationinhibiting antibodies and IgG antibodies. Completeprotection of mice against H3N2 SwIV was observed, withsignificantly reduced lung lesion and viral loads invaccine-inoculated mice relative to mock-vaccinatedcontrols. These results suggest that the GD/PR8 vaccine mayserve as a promising candidate for rapid intervention ofH3N2 SwIV outbreaks in China.

A novel M2e-multiple antigenic peptide providing heterologous protection in mice

Feng Wen,Ji-Hong Ma,Hai Yu,Fu-Ru Yang,Meng Huang,Yan-Jun Zhou,Ze-Jun Li,Xiu-Hui Wang,Guo-Xin Li,Yi-Feng Jiang,Wu Tong,Guangzhi Tong 대한수의학회 2016 Journal of Veterinary Science Vol.17 No.1

Swine influenza viruses (SwIVs) cause considerable morbidity and mortality in domestic pigs, resulting in a significant economic burden. Moreover, pigs have been considered to be a possible mixing vessel in which novel strains loom. Here, we developed and evaluated a novel M2e-multiple antigenic peptide (M2e-MAP) as a supplemental antigen for inactivated H3N2 vaccine to provide cross-protection against two main subtypes of SwIVs, H1N1 and H3N2. The novel tetra-branched MAP was constructed by fusing four copies of M2e to one copy of foreign T helper cell epitopes. A high-yield reassortant H3N2 virus was generated by plasmid based reverse genetics. The efficacy of the novel H3N2 inactivated vaccines with or without M2e-MAP supplementation was evaluated in a mouse model. M2e-MAP conjugated vaccine induced strong antibody responses in mice. Complete protection against the heterologous swine H1N1 virus was observed in mice vaccinated with M2e-MAP combined vaccine. Moreover, this novel peptide confers protection against lethal challenge of A/Puerto Rico/8/34 (H1N1). Taken together, our results suggest the combined immunization of reassortant inactivated H3N2 vaccine and the novel M2e-MAP provided cross-protection against swine and human viruses and may serve as a promising approach for influenza vaccine development.