Ternary Logic Transistors Using Multi-Stacked 2D Electron Gas Channels in Ultrathin Oxide Heterostructures.

2D electron gas field-effect transistors (2DEG-FETs), employing 2DEG formed at an interface of ultrathin (≈6 nm) AlO/ZnO heterostructure as the active channel, exhibit outstanding drive current (≈215 µA), subthreshold swing (≈132 mV dec), and field effect mobility (≈49.6 cm V s) with a high on/off current ratio of ≈10. It is demonstrated that the AlO upper layer in AlO/ZnO heterostructure acts as the source/drain resistance component during transistor operations, and the applied potential to the 2DEG channel is successfully modulated by AlO thickness variations so that the threshold voltage (V) is effectively tuned.

Biological SERS-active sensor platform based on flexible silk fibroin film and gold nanoislands.

In contrast to conventional surface-enhanced Raman scattering (SERS) platforms implemented on non-biological substrates, silk fibroin has the unique advantages of long-term biosafety and controllable biodegradability for in vitro and in vivo biomedical applications, as well as flexibility and process-compatibility. In this study, a silk fibroin film was developed to fabricate a flexible SERS sensor template with nanogap-rich gold nanoislands. The proposed biological SERS platform presents fairly good enhancements in detection performance such as detection limit, sensitivity, and signal-to-noise ratio.

Combination of Porous Silk Fibroin Substrate and Gold Nanocracks as a Novel SERS Platform for a High-Sensitivity Biosensor.

Novel concepts for developing a surface-enhanced Raman scattering (SERS) sensor based on biocompatible materials offer great potential in versatile applications, including wearable and in vivo monitoring of target analytes. Here, we report a highly sensitive SERS sensor consisting of a biocompatible silk fibroin substrate with a high porosity and gold nanocracks. Our silk-based SERS detection takes advantage of strong local field enhancement in the nanoscale crack regions induced by gold nanostructures evaporated on a porous silk substrate.

Complete Biotransformation of Protopanaxadiol-Type Ginsenosides to 20- O-β-Glucopyranosyl-20( S)-protopanaxadiol Using a Novel and Thermostable β-Glucosidase.

The ginsenoside 20- O-β-glucopyranosyl-20( S)-protopanaxadiol, compound K, has attracted much attention in functional food, traditional medicine, and cosmetic industries because of diverse pharmaceutical activities. The effective production of compound K from ginseng extracts has been required. However, an enzyme capable of completely converting all protopanaxadiol (PPD)-type ginsenosides to compound K has not been reported until now.

An L213A variant of β-glycosidase from Sulfolobus solfataricus with increased α-L-arabinofuranosidase activity converts ginsenoside Rc to compound K.

Compound K (C-K) is a crucial pharmaceutical and cosmetic component because of disease prevention and skin anti-aging effects. For industrial application of this active compound, the protopanaxadiol (PPD)-type ginsenosides should be transformed to C-K. β-Glycosidase from Sulfolobus solfataricus has been reported as an efficient C-K-producing enzyme, using glycosylated PPD-type ginsenosides as substrates.

Synergistic production of 20(S)-protopanaxadiol from protopanaxadiol-type ginsenosides by β-glycosidases from Dictyoglomus turgidum and Caldicellulosiruptor bescii.

20(S)-Protopanaxadiol (APPD) has potential uses in the pharmaceutical, cosmetic, and food industries because of its anti-stress, anti-fatigue, anti-cancer, anti-inflammatory, and anti-wrinkle properties. However, APPD production is difficult because β-glycosidases that convert the protopanaxadiol (PPD)-type ginsenoside compound K to APPD are rare. β-Glycosidase from Dictyoglomus turgidum (DT-bgl) has the highest specific activity for converting compound K to APPD, but exhibits no activity towards the α-L-arabinopyranoside moiety in compound Y.

Characterization of L-rhamnose isomerase from Clostridium stercorarium and its application to the production of D-allose from D-allulose (D-psicose).

Objective: To characterize L-rhamnose isomerase (L-RI) from the thermophilic bacterium Clostridium stercorarium and apply it to produce D-allose from D-allulose.

Results: A recombinant L-RI from C. stercorarium exhibited the highest specific activity and catalytic efficiency (k /K ) for L-rhamnose among the reported L-RIs.

Engineered Salmonella typhimurium expressing E7 fusion protein, derived from human papillomavirus, inhibits tumor growth in cervical tumor-bearing mice.

The tumor-suppressing effects of SipB160/HPV16 E7 fusion protein, derived from human papillomavirus, and expressed in Salmonella enterica serovar typhimurium, were evaluated in a cervical cancer model. The expressed E7 protein resulted in efficacious cytotoxicity and tumor growth retardation in TC-1 cervical cancer cells. In addition, in mice bearing TC-1 tumors, live cells of Salmonella expressing HPV16 E7 were administered orally and induced immune responses through interferon-gamma and tumor necrosis factor-alpha cytokine secretion and also suppressed tumor growth (45 %) and prolonged survival (70 %) compared with the control group.

Enhancement of host immune responses by oral vaccination to Salmonella enterica serovar Typhimurium harboring both FliC and FljB flagella.

Flagellin, the structural component of the flagellar filament in various motile bacteria, can contribute to the activation of NF-κB and proinflammatory cytokine expression during the innate immune response in host cells. Thus, flagellin proteins represent a particularly attractive target for the development of vaccine candidates. In this study, we investigated the immune response by increasing the flagella number in the iacP mutant strain and the adjuvant activity of the flagellin component FljB of Salmonella enterica serovar Typhimurium.

Bacteria-based in vivo peptide library screening using biopanning approach.

Traditionally, library screening has been performed to identify biologically active agents including small molecules or peptides that inhibit target proteins or molecules with therapeutic interests. Due to its chemical nature, library screening is usually performed under in vitro environments using purified proteins and molecules. However, active agents identified from in vitro screenings often fail to exhibit biological activities in cells.