Among the polycyclic aromatic hydrocarbons, although perylene is commercially available and possesses higher solubility and stability than the others, its thin-film structures and organic field-effect transistor (OFET) performances have been rarely explored. To understand its potential as an active material in OFETs, the polymorphic behaviors, packing structures, and OFET characteristics of perylene were carefully examined. The well-oriented crystal arrays of perylene prepared via droplet-pinned crystallization delivered the highest hole mobility among the reported perylene OFETs. Fluorescence microscope, electron diffraction, and lattice modeling results confirm the polymorphic behavior of perylene in the solution-processed crystal arrays and its influences on the OFET performances. The concentration-sensitive and temperature-sensitive polymorphic behavior of perylene make processing conditions crucial in the preparation of pure-phase crystal arrays. The results show the great potential of perylene as an active material in low-cost and high-performance OFETs. Moreover, the knowledge regarding the polymorphic behavior of perylene provides opportunity for the further optimization of perylene-based OFETs.

Vaccinia virus, the prototype of the Orthopoxvirus genus in the family Poxviridae, infects a wide range of cell lines and animals. Vaccinia mature virus particles of the WR strain reportedly enter HeLa cells through fluid-phase endocytosis. However, the intracellular trafficking process of the vaccinia mature virus between cellular uptake and membrane fusion remains unknown. We used live imaging of single virus particles with a combination of various cellular vesicle markers, to track fluorescent vaccinia mature virus particle movement in cells. Furthermore, we performed functional interference assays to perturb distinct vesicle trafficking processes in order to delineate the specific route undertaken by vaccinia mature virus prior to membrane fusion and virus core uncoating in cells. Our results showed that vaccinia virus traffics to early endosomes, where recycling endosome markers Rab11 and Rab22 are recruited to participate in subsequent virus trafficking prior to virus core uncoating in the cytoplasm. Furthermore, we identified WASH-VPEF/FAM21-retromer complexes that mediate endosome fission and sorting of virus-containing vesicles prior to virus core uncoating in the cytoplasm. IMPORTANCE Vaccinia mature virions of the WR strain enter HeLa cells through fluid phase endocytosis.We previously demonstrated that virus-containing vesicles are internalized into phosphatidylinositol 3-phosphate positive macropinosomes, which are then fused with Rab5-positive early endosomes. However, the subsequent process of sorting the virion-containing vesicles prior to membrane fusion remains unclear. We dissected the intracellular trafficking pathway of vaccinia mature virions in cells up to virus core uncoating in cytoplasm. We show that vaccinia mature virions first travel to early endosomes. Subsequent trafficking events require the important endosome-tethered protein VPEF/FAM21, which recruits WASH and retromer protein complexes to the endosome. There, the complex executes endosomal membrane fission and cargo sorting to the Rab11-positive and Rab22-positive recycling pathway, resulting in membrane fusion and virus core uncoating in the cytoplasm. V accinia virus is the prototype of the Orthopoxvirus genus in the family Poxviridae, which includes the variola virus that causes smallpox diseases. It has a broad host range and infects a wide variety of cell lines and animals. Vaccinia virus produces two forms of infectious virions, mature virus (MV) and extracellular virus (EV), which contain different membrane proteins (1). MV particles are abundant in infected cells and contain ϳ80 viral proteins (2, 3), which contribute to the complex virus entry processes that reportedly vary among different cells and virus strains (4-12).In HeLa cells, vaccinia MV initially attaches to cellular surface component glycosaminoglycans (13-15) and the extracellular matrix protein laminin (16). MV particles then cluster at plasma membrane lipid rafts (17) where the virus further interacts with integrin ␤1 (18) and CD98 receptor molecu...

Shikimate kinase (SK), which catalyzes the specific phosphorylation of the 3-hydroxyl group of shikimic acid in the presence of ATP, is the enzyme in the fifth step of the shikimate pathway for biosynthesis of aromatic amino acids. This pathway is present in bacteria, fungi, and plants but absent in mammals and therefore represents an attractive target pathway for the development of new antimicrobial agents, herbicides, and antiparasitic agents. Here we investigated the detailed structure–activity relationship of SK from Helicobacter pylori (HpSK). Site-directed mutagenesis and isothermal titration calorimetry studies revealed critical conserved residues (D33, F48, R57, R116, and R132) that interact with shikimate and are therefore involved in catalysis. Crystal structures of HpSK·SO4, R57A, and HpSK•shikimate-3-phosphate•ADP show a characteristic three-layer architecture and a conformationally elastic region consisting of F48, R57, R116, and R132, occupied by shikimate. The structure of the inhibitor complex, E114A•162535, was also determined, which revealed a dramatic shift in the elastic LID region and resulted in conformational locking into a distinctive form. These results reveal considerable insight into the active-site chemistry of SKs and a selective inhibitor-induced-fit mechanism.

This study examined attitudes of university faculty specialising in the field of human resource (HR) in Taiwan towards participation in the teaching of online courses using the theory of reasoned action (TRA). The population targeted for investigation consisted of the full-time university faculty in the HR field in Taiwan regardless of their experience in the teaching online courses of any kind. Survey development included a detailed literature review to identify beliefs that guided measurement construction and followed the guidelines recommended by Ajzen and Fishbein to ensure construct validity. Data were collected on TRA constructs and demographic variables using the questionnaire mailed to 278 faculty members targeted for the study. A 42% (n = 116) response rate was achieved after one round of the follow-up through emailing. The significant predictor variables, attitude and subjective social norm were confirmed. In other words, results of analyses evidenced the contribution of TRA to explaining the underlying beliefs that enhance or thwart participation. Additionally, faculty in this study possessed positive attitudes towards the participation in online teaching, and further analyses supported the use of TRA in this research context

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