Using supercomputer to finish M1 Bioinformatics Exercise from Ogata Lab

令和2年度 京都大学化学研究所 スーパーコンピュータシステム 利用報告

Dynamic interactions of a conserved enterotoxigenic Escherichia coli adhesin with intestinal mucins govern epithelium engagement and toxin delivery

At present, there is no vaccine for enterotoxigenic Escherichia coli (ETEC), an important cause of diarrheal illness. Nevertheless, recent microbial pathogenesis studies have identified a number of molecules produced by ETEC that contribute to its virulence and are novel antigenic targets to complement canonical vaccine approaches. EtpA is a secreted two-partner adhesin that is conserved within the ETEC pathovar. EtpA interacts with the tips of ETEC flagella to promote bacterial adhesion, toxin delivery, and intestinal colonization by forming molecular bridges between the bacteria and the epithelial surface. However, the nature of EtpA interactions with the intestinal epithelium remains poorly defined. Here, we demonstrate that EtpA interacts with glycans presented by transmembrane and secreted intestinal mucins at epithelial surfaces to facilitate pathogen-host interactions that culminate in toxin delivery. Moreover, we found that a major effector molecule of ETEC, the heat-labile enterotoxin (LT), may enhance these interactions by stimulating the production of the gel-forming mucin MUC2. Our studies suggest, however, that EtpA participates in complex and dynamic interactions between ETEC and the gastrointestinal mucosae in which host glycoproteins promote bacterial attachment while simultaneously limiting the epithelial engagement required for effective toxin delivery. Collectively, these data provide additional insight into the intricate nature of ETEC interactions with the intestinal epithelium that have potential implications for rational approaches to vaccine design

2-(Methoxy­meth­yl)adamantan-2-yl 2-methyl­acrylate

The title compound, C16H24O3, has a cage-type mol­ecular structure and is of inter­est with respect to its photochemical properties. The structure displays non-classical inter­molecular C—H⋯O hydrogen bonding, which links the mol­ecules into a three-dimensional network

Magnesia-stabilised zirconia solid electrolyte assisted electrochemical investigation of iron ions in the SiO2-CaO-MgO-Al2O3 molten slag at 1723 K

Production of metallic iron through molten oxide electrolysis using inert electrodes is an alternative route for fast ironmaking without CO2 emissions. The fact that many inorganic oxides melt at ultrahigh temperatures (>1500 K) challenges conventional electro-analytical techniques used in aqueous, organic and molten salt electrolytes. However, in order to design a feasible and effective electrolytic process, it is necessary to best understand the electrochemical properties of iron ions in molten oxide electrolytes. In this work, a magnesia-stabilised zirconia (MSZ) tube with a closed end was used to construct an integrated three-electrode cell with the “MSZ | Pt | O2 (air)” assembly functioning as the solid electrolyte, the reference electrode and also the counter electrode. Electrochemical reduction of iron ions was systematically investigated on an iridium (Ir) wire working electrode in the SiO2-CaO-MgO-Al2O3 molten slag at 1723 K by cyclic voltammetry (CV), square wave voltammetry (SWV), chronopotentiometry (CP) and potentiostatic electrolysis (PE). The results show that the electro-reduction of the Fe2+ ion to Fe on the Ir electrode in the molten slag follows a single two-electron transfer step, and the rate of the process is diffusion controlled. The peak current on the obtained CVs is proportional to the concentration of the Fe2+ ion in the molten slag and the square root of scan rate. The diffusion coefficient of Fe2+ ions in the molten slag containing 5 wt% FeO at 1723 K was derived to be (3.43 ± 0.06)×10-6 cm2 s-1 from CP analysis. However, a couple of following processes, i.e. alloy formation on the Ir electrode surface and interdiffusion were found to affect the kinetics of iron deposition. An ECC mechanism is proposed to account for the CV observations. The findings from this work confirm that zirconia-based solid electrolytes can play an important role in electrochemical fundamental research in high temperature molten slag electrolytes

Stormwater Quality Characteristics and Reuse Analysis of Different Underlying Surfaces at Wanzhou North Station

In response to the water shortage in Wanzhou North Station (WNS), the authors investigated the stormwater quality characteristics with different underlying surfaces of WNS and carried out stormwater reuse analysis in conjunction with the InfoWorks ICM model. The results show that during heavy, torrential, and moderate rainfall, the road stormwater runoff has the highest concentrations of pollutants, with an average EMC (event mean concentration) value of 206 mg/L for COD. For the square runoff, the average EMC values of COD, SS, TN, and TP are 108 mg/L, 395 mg/L, 2.113 mg/L, and 0.128 mg/L, in comparison, the average EMC values of the corresponding indexes for the roof runoff are 65 mg/L, 212 mg/L, 1.449 mg/L, and 0.086 mg/L, respectively, demonstrating their potential for reuse. The R2 (coefficient of determination) of SS and COD in both roof and square runoff are greater than 0.85, with a good correlation, indicating that SS removal is the key to stormwater purification. InfoWorks ICM analysis shows that the recyclable volume of rainwater from WNS in 2018 is 29,410 m3 , accounting for 61.8% of the total annual rainfall. This study is expected to provide an ideal reference for the stormwater management of public buildings in mountainous areas