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We have developed a compact ultrafast electron diffractometer, consisting of a laser-driven rf photocathode that generates 3.0 MeV probe electron pulses, three-stage lens optics, and a custom-built detector for relativistic electrons. High-quality single-shot transmission electron diffraction has been detected from 180-nm-thick Si single crystals, with an excellent special resolution for diffracted beams; the spot width of 0.02 A-1 is obtained. The pulse width is estimated to be 100 fs in duration. Characteristics of the electron beam and other diffractometer features are discussed. [ABSTRACT FROM AUTHOR]

This study presents an integrated system for object recognition, six-degrees-of-freedom pose estimation, and dexterous manipulation using a JACO robotic arm with an Intel RealSense D435 camera. This system is designed to automate the manipulation of industrial valves by capturing point clouds (PCs) from multiple perspectives to improve the accuracy of pose estimation. The object recognition module includes scene segmentation, geometric primitives recognition, model recognition, and a color-based clustering and integration approach enhanced by a dynamic cluster merging algorithm. Pose estimation is achieved using the random sample consensus algorithm, which predicts position and orientation. The system was tested within a 60° field of view, which extended in all directions in front of the object. The experimental results show that the system performs reliably within acceptable error thresholds for both position and orientation when the objects are within a ±15° range of the camera's direct view. However, errors increased with more extreme object orientations and distances, particularly when estimating the orientation of ball valves. A zone-based dexterous manipulation strategy was developed to overcome these challenges, where the system adjusts the camera position for optimal conditions. This approach mitigates larger errors in difficult scenarios, enhancing overall system reliability. The key contributions of this research include a novel method for improving object recognition and pose estimation, a technique for increasing the accuracy of pose estimation, and the development of a robot motion model for dexterous manipulation in industrial settings.

CXCL14 is a primordial CXC-type chemokine that transports CpG oligodeoxynucleotides (ODN) into endosomes and lysosomes in dendritic cells, thereby leading to the activation of the Toll-like receptor 9 (TLR9)-mediated innate immune system. However, the underlying molecular mechanism by which the CXCL14-CpG ODN complex enters cells remains elusive. Herein, we describe the chemical synthesis of CXCL14-derived photoaffinity probes and their application to the identification of target receptors for CXCL14 using quantitative proteomics. By utilizing native chemical ligation and maleimide-thiol coupling chemistry, we synthesized site-specifically modified CXCL14-based photoaffinity probes that contain photoreactive 2-aryl-5-carboxytetrazole (ACT) and a hydrazine-labile cleavable linker. CXCL14-based probes were found to be capable of binding CpG ODN to immune cells, whose bioactivities were comparable to native CXCL14. Application of CXCL14-derived probes to quantitative proteomic experiments enabled the identification of dozens of target receptor candidates for CXCL14 in mouse macrophage-derived RAW264.7 cells, and we discovered that low-density lipoprotein receptor-related protein 1 (LRP1) is a novel receptor for CXCL14 by competitive proteome profiling. We further showed that disruption of LRP1 affected the incorporation of the CXCL14-CpG ODN complex in the cells. Overall, this report highlights the power of synthetic CXCL14-derived photoaffinity probes combined with chemical proteomics to discover previously unidentified receptors for CXCL14, which could promote an understanding of the molecular functions of CXCL14 and the elaborate machinery of innate immune systems.

Alzheimer's disease is a neurologic disorder characterized by the accumulation of extracellular deposits of amyloid-β (Aβ) fibrils in the brain of patients. The key etiologic agent in Alzheimer's disease is not known; however oligomeric Aβ appears detrimental to neuronal functions and increases Aβ fibrils deposition. Previous research has shown that curcumin, a phenolic pigment of turmeric, has an effect on Aβ assemblies, although the mechanism remains unclear. In this study, we demonstrate that curcumin disassembles pentameric oligomers made from synthetic Aβ42 peptides (pentameric oAβ42), using atomic force microscopy imaging followed by Gaussian analysis. Since curcumin shows keto-enol structural isomerism (tautomerism), the effect of keto-enol tautomerism on its disassembly was investigated. We have found that curcumin derivatives capable of keto-enol tautomerization also disassemble pentameric oAβ42, while, a curcumin derivative incapable of tautomerization did not affect the integrity of pentameric oAβ42. These experimental findings indicate that keto-enol tautomerism plays an essential role in the disassembly. We propose a mechanism for oAβ42 disassembly by curcumin based on molecular dynamics calculations of the tautomerism. When curcumin and its derivatives bind to the hydrophobic regions of oAβ42, the keto-form changes predominantly to the enol-form; this transition is associated with structural (twisting, planarization and rigidification) and potential energy changes that give curcumin enough force to act as a torsion molecular-spring that eventually disassembles pentameric oAβ42. This proposed mechanism sheds new light on keto-enol tautomerism as a relevant chemical feature for designing such novel therapeutic drugs that target protein aggregation., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Nobuyasu Naruse reports financial support was provided by Grant-in-Aid for Scientific Research (C) from the Japan Society for the Promotion of Science (KAKENHI) Grant Number 19K05207. Nobuyasu Naruse reports a relationship with the Japan Society for the Promotion of Science that includes: funding grants. Nobuyasu Naruse has patent pending to Nobuyasu Naruse. The authors declare no competing interest., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

This study demonstrates a simultaneous realization of ultralow thermal conductivity and high thermoelectric power factor in epitaxial GeTe thin films/Si substrates by a combination of the interface introduction by domain engineering and the suppression of Ge vacancy generation by point defect control. We formed epitaxial Te-poor GeTe thin films having low-angle grain boundaries with a misorientation angle close to 0° or twin interfaces with a misorientation angle close to 180°. The control of interfaces and point defects gave rise to ultralow lattice thermal conductivity of ∼0.7 ± 0.2 W m -1 K -1 . This value was the same in the order of magnitude as the theoretical minimum lattice thermal conductivity of ∼0.5 W m -1 K -1 calculated by the Cahill-Pohl model. At the same time, the GeTe thin films exhibited a high thermoelectric power factor because of the suppression of Ge vacancy generation and a small contribution of grain boundary carrier scattering. The outstanding combined technique of domain engineering and point defect control can be a great approach for developing high-performance thermoelectric films.

Vanadium dioxide (VO 2 ) material, known for changing physical properties due to metal-insulator transition (MIT) near room temperature, has been reported to undergo a phase change depending on the strain. This fact can be a significant problem for nanoscale devices in VO 2 , where the strain field covers a large area fraction, spatially non-uniform, and the amount of strain can vary during the MIT process. Direct measurement of the strain field distribution during MIT is expected to establish a methodology for material phase identification. We have demonstrated the effectiveness of geometric phase analysis (GPA), high-resolution transmission electron microscopy techniques, and transmission electron diffraction (TED). The GPA images show that the nanoregions of interest are under tensile strain conditions of less than 0.4% as well as a compressive strain of about 0.7% (Rutile phase VO 2 [100] direction), indicating that the origin of the newly emerged TED spots in MIT contains a triclinic phase. This study provides a substantial understanding of the strain-temperature phase diagram and strain engineering strategies for effective phase management of nanoscale VO 2 ., Competing Interests: No potential conflict of interest was reported by the authors., (© 2022 The Author(s). Published by National Institute for Materials Science in partnership with Taylor & Francis Group.)

A 60-year-old man with type 2 diabetes mellitus treated with a dipeptidyl peptidase-4 (DPP-4) inhibitor was referred to our hospital because of his refractory watery diarrhea. Ileocolonoscopy revealed increased capillary growth, fine granular mucosa, and longitudinal mucosal tears mainly in the left side of the colon. A bioptic examination revealed thickened subepithelial collagen bands, thus confirming the diagnosis of collagenous colitis. Systemic steroid therapy was initiated, but his symptoms recurred when tapering the steroid. However, withdrawal of the DPP-4 inhibitor was successful even after the cessation of steroid therapy. We therefore considered his collagenous colitis to have been caused by the DPP-4 inhibitor.

Background and Aim: The present study aimed to compare the utility and safety of the colonic self-expandable metallic stent between patients with obstructive primary colorectal cancer who underwent chemotherapy or palliative treatment care and patients bridging for surgery., Methods: The cases of 71 patients with colonic obstructive stenosis and in-dwelling stents who were hospitalized between May 2012 and April 2020 at Karatsu Red Cross Hospital were retrospectively analyzed. The patients were classified into three groups: bridging for curative surgery (group I), receiving systemic chemotherapy (group II-A), and receiving only palliative treatment (group II-B). Technical and clinical success rates and complication rates after stenting were evaluated., Results: No significant differences were observed in the technical (procedure) success rates (group I: 100%; group II, 97.6% [II-A: 100%; II-B: 95.8%]). The total clinical success rate was 85.9% (61/71) and did not vary significantly among the groups (group I: 82.8%; group II 88.0% [II-A: 83.3%; II-B: 91.6%]). No significant differences were observed in the early complication rates between groups I and II and in the late complication rates between groups II-A and II-B. Nutrition status, general condition, tumor staging, and 1-year survival were poorer in group II than in group I., Conclusion: The findings show that colonic stenting for malignant obstruction was performed successfully and safely both in patients who received systemic chemotherapy or palliative therapy and in patients bridging for curative surgery, regardless of risk status for malnutrition, poor general condition, cancer stage progression, and short survival., (© 2022 The Authors. JGH Open published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

The most common type of dementia, Alzheimer's disease, is associated with senile plaques formed by the filamentous aggregation of hydrophobic amyloid-β (Aβ) in the brains of patients. Small oligomeric assemblies also occur and drugs and chemical compounds that can interact with such assemblies have attracted much attention. However, these compounds need to be solubilized in appropriate solvents, such as ethanol, which may also destabilize their protein structures. As the impact of ethanol on oligomeric Aβ assembly is unknown, we investigated the effect of various concentrations of ethanol (0 to 7.2 M) on Aβ pentameric assemblies (Aβp) by combining blue native-PAGE (BN-PAGE) and ambient air atomic force microscopy (AFM). This approach was proven to be very convenient and reliable for the quantitative analysis of Aβ assembly. The Gaussian analysis of the height histogram obtained from the AFM images was correlated with band intensity on BN-PAGE for the quantitative estimation of Aβp. Our observations indicated up to 1.4 M (8.3%) of added ethanol can be used as a solvent/vehicle without quantitatively affecting Aβ pentamer stability. Higher concentration induced significant destabilization of Aβp and eventually resulted in the complete disassembly of Aβp.

Some CXC chemokines, including CXCL14, transport CpG oligodeoxynucleotides (ODNs) into dendritic cells (DCs), thereby activating TLR9. The molecular basis of this noncanonical function of CXC chemokines is not well understood. In this study, we investigated the CpG ODN binding and intracellular transport activities of various CXC chemokines and partial peptides of CXCL14 in mouse bone marrow-derived dendritic cells. CXCL14, CXCL4, and CXCL12 specifically bound CpG ODN, but CXCL12 failed to transport it into cells at low dose. CXCL14 N-terminal peptides 1-47, but not 1-40, was capable of transporting CpG ODN into the cell, resulting in an increase in cytokine production. However, both the 1-47 and 1-40 peptides bound CpG ODN. By contrast, CXCL14 peptides 13-50 did not possess CpG ODN binding capacity or transport activity. The chimeric peptides CXCL12 (1-22)-CXCL14 (13-47) bound CpG ODN but failed to transport it. These results suggest that amino acids 1-12 and 41-47 of CXCL14 are required for binding and intracellular transport of CpG ODN, respectively. We found that an anti-CXCL14 Ab blocked cell-surface binding and internalization of the CpG ODN/CXCL14 complex. On the basis of these findings, we propose that CXCL14 has two functional domains, one involved in DNA recognition and the other in internalization of CXCL14-CpG DNA complex via an unidentified CXCL14 receptor, which together are responsible for eliciting the CXCL14/CpG ODN-mediated TLR9 activation. These domains could play roles in CXCL14-related diseases such as arthritis, obesity-induced diabetes, and various types of carcinoma., (Copyright © 2021 by The American Association of Immunologists, Inc.)

Phonon transport in the nano-system has been studied using well-designed nanostructured materials to observe and control the interesting phonon behaviors like ballistic phonon transport. Recently, we observed drastic thermal conductivity reduction in the films containing well-controlled nanodots. Here, we investigate whether this comes from the interference effect in ballistic phonon transport by comparing the thermal properties of the Si or Si0.75Ge0.25 films containing Ge nanodots. The experimentally-obtained thermal resistance of the nanodot layer shows peculiar nanodot size dependence in the Si films and a constant value in the SiGe films. From the phonon simulation results, interestingly, it is clearly found that in the nanostructured Si film, phonons travel in a non-diffusive way (ballistic phonon transport). On the other hand, in the nanostructured SiGe film, although simple diffusive phonon transport occurs, extremely-low thermal conductivity (∼0.81 W m-1 K-1) close to that of amorphous Si0.7Ge0.3 (∼0.7 W m-1 K-1) is achieved due to the combination of the alloy phonon scattering and Ge nanodot scattering.

Metal-organic 1D-coordination polymers, having unique electronic and optical properties, are expected to be a novel advanced functional material capable of fabricating smart plastics, films, and fibers. In this study, we have synthesized a novel metal-organic 1D-coordination polymer composed of a phenylene-bridged bipyrrole bearing N -alkylimino groups (BPI) and palladium(II) ion. The BPI and Pd(II) form square planar bis(bidentate) complex to form a metal coordinated π-conjugation polymer (Poly-BPI/Pd). It is stable in solutions at room temperature, and allowed measurement of its average molecular weight in SEC ( M w = 106,000 and M n = 18,000, M w / M n = 5.88). It also provided a reversible multi redox profile in cyclic voltammetry, most likely originating from strong π-electronic interactions between the BPI components via Pd ion. A variety of substituent groups can be attached to the imino-nitrogens of BPI. A coordination polymer composed of a BPI derivative bearing chiral alkyl chains and Pd(II) showed strong circular dichroism (CD) in the solution due to the unidirectional chiral conformation of the BPI components in the polymer backbone., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Nishinaka, Han, Han, Liu, Du, Wang, Eerdun, Naruse, Mera, Furusho and Tsuda.)

Aim: The objective of the current study was to identify risk factors that affect the onset of dependence and chronic psychosis due to cannabis use., Methods: We examined clinical genetic factors, psychiatric disorders prior to cannabis use, starting age of cannabis use, duration and frequency of cannabis use, types of cannabis products used, combined use of other psychoactive substances, and the psychiatric diagnosis of 71 patients with cannabis-related psychiatric disorders who underwent treatment at nine mental health hospitals in Japan. Information was collected from cross-sectional interview surveys conducted by each patient's attending psychiatrist., Results: For the diagnosis of dependence syndrome due to the use of cannabis, we found associations with the number of years of cannabis use and the use of cannabis products with a high Δ9-tetrahydrocannabinol (THC) content. However, we found no association between diagnosis of residual and late-onset psychotic disorders and clinical genetic factors, presence of preceding psychiatric disorders, duration and frequency of cannabis use, starting age of cannabis use, or combined use of other psychoactive substances; an association was found only for the absence of use of cannabis products other than dried cannabis., Conclusion: The onset of cannabis dependence was related to long-term cannabis use and the use of cannabis products with a high THC content. However, chronic psychosis was not associated with total THC intake or psychiatric vulnerability. Thus, unknown factors appear to be involved in the onset of chronic psychosis., (© 2020 The Authors. Neuropsychopharmacology Reports published by John Wiley & Sons Australia, Ltd on behalf of The Japanese Society of Neuropsycho Pharmacology.)

Ring-opening by CuSO 4 of a 1,3-thiazolidine carbonyl structure (Thz) as an N-terminal cysteine (Cys) residue revealed that an intramolecular S-acetamidomethyl cysteine (Cys(Acm)) can also be deprotected with concomitant formation of a disulphide bond connecting the two Cys residues. A mechanistic study on the disulphide formation led to a general protocol for deprotection of the S-Acm group by CuSO 4 and a 1,2-aminothiol under aerobic conditions. Application of this new deprotection reaction allowed for the synthesis of Apamin, a peptide with two-disulphides in a one-pot/stepwise disulphide-bridging procedure.

A Si-based superlattice is one of the promising thermoelectric films for realizing a stand-alone single-chip power supply. Unlike a p-type superlattice (SL) achieving a higher power factor due to strain-induced high hole mobility, in the n-type SL, the strain can degrade the power factor due to lifting conduction band degeneracy. Here, we propose epitaxial Si-rich SiGe/Si SLs with ultrathin Ge segregation interface layers. The ultrathin interface layers are designed to be sufficiently strained, not to give strain to the above Si layers. Therein, a drastic thermal conductivity reduction occurs by larger phonon scattering at the interfaces with the large atomic size difference between Si layers and Ge segregation layers, while unstrained Si layers preserve a high conduction band degeneracy leading to a high Seebeck coefficient. As a result, the n-type Si 0.7 Ge 0.3 /Si SL with controlled interfaces achieves a higher power factor of ∼25 μW cm -1 K -2 in the in-plane direction at room temperature, which is superior to ever reported SiGe-based films: SiGe-based SLs and SiGe films. The Si 0.7 Ge 0.3 /Si SL with controlled interfaces also exhibits a low thermal conductivity of ∼2.5 W m -1 K -1 in the cross-plane direction, which is ∼5 times lower than the reported value in a conventional Si 0.7 Ge 0.3 /Si SL. These results demonstrate that strain and atomic differences controlled by ultrathin layers can bring a breakthrough for realizing high-performance light-element-based thermoelectric films.

For realization of new informative systems, the memristor working like synapse has drawn much attention. We developed isolated high-density Fe 3 O 4 nanocrystals on Ge nuclei/Si with uniform and high resistive switching performance using low-temperature growth. The Fe 3 O 4 nanocrystals on Ge nuclei had a well-controlled interface (Fe 3 O 4 /GeO x /Ge) composed of high-crystallinity Fe 3 O 4 and high-quality GeO x layers. The nanocrystals showed uniform resistive switching characteristics (high switching probability of ~90%) and relatively high Off/On resistance ratio (~58). The high-quality interface enables electric field application to Fe 3 O 4 and GeO x near the interface, which leads to effective positively charged oxygen vacancy movement, resulting in high-performance resistive switching. Furthermore, we successfully observed memory effect in nanocrystals with well-controlled interface. The experimental confirmation of the memory effect existence even in ultrasmall nanocrystals is significant for realizing non-volatile nanocrystal memory leading to neuromorphic devices., (© 2020 The Author(s). Published by National Institute for Materials Science in partnership with Taylor & Francis Group.)

Cupric sulfate efficiently opens thiazolidine and selenazolidine rings, producing a protected N-terminal cysteine or selenocysteine derivative without the use of inert gas or solvent. This is a clear advantage over methods that use water-soluble palladium salts, which fail to react with the selenazolidine ring. This copper-mediated reaction proceeds with monovalent or divalent copper ions, and disulfide bond formation followed by ring-opening promotes the process. This copper-mediated reaction, which is compatible with the standard native chemical ligation conditions, was applied to the synthesis of the 77-mer CXCL14 protein.

Background: Methamphetamine (METH) is one of the most widely distributed psychostimulants worldwide. Despite active counter measures taken by different countries, neither overall usage of METH nor the frequency of repeat users has reduced over the past decade. METH induces abuse and dependence as it acts on the central nervous system and temporarily stimulates the brain. The recidivism rate for abuse of stimulants in Japan is very high and therefore prevention of repeated usage is paramount. However, we lack information about the relationship between METH users and genomic changes in humans in Japan, which would provide important information to aid such efforts., Objective: Shati/Nat8l is a METH-inducible molecule and its overexpression has protective effects on the brain upon METH usage. Here we investigated the effect of METH usage on DNA methylation rates at the promoter site of SHATI/NAT8L. We used DNA samples from human METH users, who are usually difficult to recruit in Japan., Methods: We measured DNA methylation at SHATI/NAT8L promoter sites by pyrosequencing method using 193 samples of METH users and 60 samples of healthy subjects. In this method, DNA methylation is measured by utilizing the property that only non-methylated cytosine changes to urasil after bisulfite conversion., Results: We found that the rate of DNA methylation at six CpG islands of SHATI/NAT8L promoter sites is significantly higher in METH users when compared to healthy subjects., Conclusion: These results suggest that the DNA methylation rate of SHATI/NAT8L promotor regions offers a new diagnostic method for METH usage., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Aims: The use of new psychoactive substances (NPS) has become increasingly widespread over the last decade, in Japan and internationally. NPS are associated with a range of increasingly serious clinical, public, and social issues. Political measures to ameliorate the effects of NPS in Japan have focused on tightening regulation rather than establishing treatment methods. The current study sought to compare the neuropsychiatric symptoms of patients with NPS-related disorders across several years. We examined patients who attended specialized hospitals for treating addiction, to elucidate the impacts of legal measures to control NPS., Methods: Subjects (n = 864) were patients with NPS-related disorders who received medical treatment at eight specialized hospitals for treating addiction in Japan between April 2012 and March 2015. Clinical information was collected retrospectively from medical records., Results: Among psychiatric symptoms, the ratio of hallucinations/delusions decreased over time across 3 years of study (first year vs second year vs third year: 40.1% vs 30.9% vs 31.7%, P = 0.037). Among neurological symptoms, the ratio of coma/syncope increased over the 3-year period (7.8% vs 11.0% vs 17.0%, P = 0.002), as did the ratio of convulsions (2.8% vs 4.3% vs 9.7%, P = 0.001)., Conclusion: The symptoms associated with NPS were primarily psychiatric in the first year, while the prevalence of neurological symptoms increased each year. The risk of death and the severity of symptoms were greater in the third year compared with the first year, as regulation of NPS increased., (© 2019 The Authors. Neuropsychopharmacology Reports published by John Wiley & Sons Australia, Ltd on behalf of The Japanese Society of Neuropsychopharmacology.)

The simultaneous realization of low thermal conductivity and high thermoelectric power factor in materials has long been the goal for the social use of high-performance thermoelectric modules. Nanostructuring approaches have drawn considerable attention because of the success in reducing thermal conductivity. On the contrary, enhancement of the thermoelectric power factor, namely, the simultaneous increase of the Seebeck coefficient and electrical conductivity, has been difficult. We propose a method for the power factor enhancement by introducing coherent homoepitaxial interfaces with controlled dopant concentration, which enables the quasiballistic transmission of high-energy carriers. The wavenumber of the high-energy carriers is nearly conserved through the interfaces, resulting in simultaneous realization of a high Seebeck coefficient and relatively high electrical mobility. Here, we experimentally demonstrate the dopant-controlled epitaxial interface effect for the thermoelectric power factor enhancement using our "embedded-ZnO nanowire structure" having high-quality nanowire interfaces. This presents the methodology for substantial power factor enhancement by interface carrier scattering.

The resin-bound N-sulfanylethylanilide (SEAlide) peptide was found to function as a crypto-thioester peptide. Exposure of the peptide resin to an aqueous solution under neutral conditions in the presence of thiols affords thioesters without accompanying racemization of C-terminal amino acids. Furthermore, the resin-bound SEAlide peptides react with N-terminal cysteinyl peptides in the absence of phosphate salts to afford ligated products, whereas soluble SEAlide peptides do not. This unexpected difference in reactivity of the SEAlide peptides allows for a one-pot/three-fragment ligation using resin-bound and unbound peptides.

CXCL14 is a primordial chemokine that plays multiple roles in tumor suppression, autoimmune arthritis, and obesity-associated insulin resistance. However, the underlying molecular mechanisms are unclear. Here, we show that CXCL14 transports various types of CpG oligodeoxynucleotide (ODN) into the endosomes and lysosomes of bone marrow-derived dendritic cells (DCs), thereby activating Toll-like receptor 9 (TLR9). A combination of CpG ODN (ODN2395) plus CXCL14 induced robust production of IL-12 p40 by wild-type, but not Tlr9-knockout, DCs. Consistent with this, ODN2395-mediated activation of DCs was significantly attenuated in Cxcl14-knockout mice. CXCL14 bound CpG ODN with high affinity at pH7.5, but not at pH6.0, thereby enabling efficient delivery of CpG ODN to TLR9 in the endosome/lysosome. Furthermore, the CXCL14-CpG ODN complex specifically bound to high affinity CXCL14 receptors on DCs. Thus, CXCL14 serves as a specific carrier of CpG DNA to sensitize TLR9-mediated immunosurveillance., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

A synthetic protocol for the preparation of 162-residue S-monoglycosylated GM2-activator protein (GM2AP) analogues bearing various amino acid substitutions for Thr69 has been developed. The facile incorporation of the replacements into the protein was achieved by means of a one-pot/N-to-C-directed sequential ligation strategy using readily accessible middle N-sulfanylethylanilide (SEAlide) peptides each consisting of seven amino acid residues. A kinetically controlled ligation protocol was successfully applied to the assembly of three peptide segments covering the GM2AP. The native chemical ligation (NCL) reactivities of the SEAlide peptides can be tuned by the presence or absence of phosphate salts. Furthermore, NCL of the alkyl thioester fragment [GM2AP (1-31)] with the N-terminal cysteinyl prolyl thioester [GM2AP (32-67)] proceeded smoothly to yield the 67-residue prolyl thioester, with the prolyl thioester moiety remaining intact. This newly developed strategy enabled the facile synthesis of GM2AP analogues. Thus, we refer to this synthetic protocol as "tailored synthesis" for the construction of a GM2AP library., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)