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Abstract Cyclic lipopeptides (CLPs) produced by the genus Bacillus are amphiphiles composed of hydrophilic amino acid and hydrophobic fatty acid moieties and are biosynthesised by non-ribosomal peptide synthetases (NRPSs). CLPs are produced as a mixture of homologues with different fatty acid moieties, whose length affects CLP activity. Iturin family lipopeptides are a family of CLPs comprising cyclic heptapeptides and β-amino fatty acids and have antimicrobial activity. There is little research on how the length of the fatty acid moiety of iturin family lipopeptides is determined. Here, we demonstrated that the acyl ligase (AL) domain determines the length of the fatty acid moiety in vivo. In addition, enzyme assays revealed how mutations in the substrate-binding pocket of the AL domain affected substrate specificity in vitro. Our findings have implications for the design of fatty acyl moieties for CLP synthesis using NRPS.

This study comprehensively investigates how rain and drizzle affect the object-detection performance of non-contact safety sensors, which are essential for the operation of unmanned aerial vehicles and ground vehicles in adverse weather conditions. In contrast to conventional sensor-performance evaluation based on the amount of precipitation, this paper proposes spatial transmittance and particle density as more appropriate metrics for rain environments. Through detailed experiments conducted under a variety of precipitation conditions, it is shown that sensor performance is significantly affected by the density of small raindrops rather than the total amount of precipitation. This finding challenges traditional sensor-evaluation metrics in rainfall environments and suggests a paradigm shift toward the use of spatial transmittance as a universal metric for evaluating sensor performance in rain, drizzle, and potentially other adverse weather scenarios.

Noroviruses have been identified as major causative agents of acute nonbacterial gastroenteritis in humans. Histo‐blood group antigens (HBGAs) are thought to play a major role among the host cellular factors influencing norovirus infection. Genogroup I, genotype 9 (GI.9) is the most recently identified genotype within genogroup I, whose representative strain is the Vancouver 730 norovirus. However, the molecular interactions between host antigens and the GI.9 capsid protein have not been investigated in detail. In this study, we demonstrate that the GI.9 norovirus preferentially binds Lewis antigens over blood group A, B, and H antigens, as revealed by an HBGA binding assay using virus‐like particles. We determined the crystal structures of the protruding domain of the GI.9 capsid protein in the presence or absence of Lewis antigens. Our analysis demonstrated that Lewis fucose (α1–3/4 fucose) represents a key moiety for the GI.9 protein–HBGA interaction, thus suggesting that Lewis antigens might play a critical role during norovirus infection. In addition to previously reported findings, our observations may support the future design of antiviral agents and vaccines against noroviruses.

Kinesin superfamily proteins are microtubule-based molecular motors driven by the energy of ATP hydrolysis. Among them, the kinesin-4 family is a unique motor that inhibits microtubule dynamics. Although mutations of kinesin-4 cause several diseases, its molecular mechanism is unclear because of the difficulty of visualizing the high-resolution structure of kinesin-4 working at the microtubule plus-end. Here, we report that KLP-12, a C. elegans kinesin-4 ortholog of KIF21A and KIF21B, is essential for proper length control of C. elegans axons, and its motor domain represses microtubule polymerization in vitro. The crystal structure of the KLP-12 motor domain complexed with tubulin, which represents the high-resolution structural snapshot of the inhibition state of microtubule-end dynamics, revealed the bending effect of KLP-12 for tubulin. Comparison with the KIF5B-tubulin and KIF2C-tubulin complexes, which represent the elongation and shrinking forms of microtubule ends, respectively, showed the curvature of tubulin introduced by KLP-12 is in between them. Taken together, KLP-12 controls the proper length of axons by modulating the curvature of the microtubule ends to inhibit the microtubule dynamics.

Microtubules are dynamic polymers consisting of αβ-tubulin heterodimers. The initial polymerization process, called microtubule nucleation, occurs spontaneously via αβ-tubulin. Since a large energy barrier prevents microtubule nucleation in cells, the γ-tubulin ring complex is recruited to the centrosome to overcome the nucleation barrier. However, a considerable number of microtubules can polymerize independently of the centrosome in various cell types. Here, we present evidence that the minus-end-binding calmodulin-regulated spectrin-associated protein 2 (CAMSAP2) serves as a strong nucleator for microtubule formation by significantly reducing the nucleation barrier. CAMSAP2 co-condensates with αβ-tubulin via a phase separation process, producing plenty of nucleation intermediates. Microtubules then radiate from the co-condensates, resulting in aster-like structure formation. CAMSAP2 localizes at the co-condensates and decorates the radiating microtubule lattices to some extent. Taken together, these in vitro findings suggest that CAMSAP2 supports microtubule nucleation and growth by organizing a nucleation centre as well as by stabilizing microtubule intermediates and growing microtubules.

Abstract Here, a gated‐anode diode (GAD) is proposed where an anode electrode is formed by connecting a gate electrode and an ohmic electrode of a normally‐off GaN HEMT for a 5.8 GHz rectenna. A wide recessed gate GaN GADs were prepared and the recess length dependence of their electrical characteristics was investigated. Typical DC characteristics of the HEMTs are a threshold voltage (Vth) of +0.3 V and a maximum drain current (Imax) of 300 mA/mm. The GADs showed the characteristics of maximum forward current (If) of 350 mA/mm, reverse breakdown voltage (BVr) of 40 V, and off‐state capacitance (Coff) of 0.28 pF/mm by using optimized recess length. We constructed SPICE model of the GADs. The SPICE simulation predicted a rectifier efficiency of 81% and a DC output power of 10 W for bridge type 5.8 GHz rectifier using four GADs with each gate width of 0.8 mm.

A taxonomia da humanidade pode ser ditada por inúmeras categorias: civilização, raça, etnia, tradição, cultura e assim por diante. Enquanto percebidas frequentemente apenas como descritivas e “fixadas naturalmente”, nenhuma dessas categorias é capaz de especificar a identidade de um grupo particular sem cometer alguma inconsistência conceitual ou oferecer uma classificação razoavelmente coerente e sistemática da espécie humana em geral. Ainda assim, é impossível dizer que elas são irreais ou meramente ilusórias. Ao contrário, constituem a realidade social e cumprem papéis significativos na discriminação de um grupo de pessoas de e em oposição a outros. O Ocidente – da mesma forma, com seu oposto simétrico, o Resto da humanidade – é uma dessas categorias claramente defeituosas na racionalidade de sua coerência conceitual. Ela não tem unidade de consistência. Antes, se apresenta como uma unidade putativa, e contém em si contradições, de modo a poder ser unificada apenas no futuro. É um imaginário social que funciona principalmente como um mito em escala global, tal como a raça. Ainda assim, ao contrário da raça, ela tende a apresentar uma associação cartográfica. Devido a essa afinidade com a imaginação cartográfica, a dicotomia entre o Ocidente e o Resto é frequentemente invocada como tropo esquemático de diálogo a fim de denotar e compreender diversas instâncias de conflito social e distanciamento em termos espaciais, mas com o resultado de postular o Ocidente e o Resto como territórios, como delimitações geográficas. Este artigo questiona, então, como pode o Ocidente existir?

A figure in the article by Baba et al. [(2021), J. Synchrotron Rad. 28, 1284–1295] is corrected.

Abstract Cysteine-rich peptides (CRPs) of 2–6 kDa are generally thermally and proteolytically stable because of their multiple cross-bracing disulfide bonds. Here, we report the discovery and characterization of two novel cystine-stapled CRPs, designated lybatide 1 and 2 (lyba1 and lyba2), from the cortex of Lycium barbarum root. Lybatides, 32 to 33 amino acids in length, are hyperstable and display a novel disulfide connectivity with a cysteine motif of C-C-C-C-CC-CC which contains two pairs of adjacent cysteines (-CC-CC). X-ray structure analysis revealed the presence of a single cystine-stabilized (α + π)-helix in lyba2, a rare feature of CRPs. Together, our results suggest that lybatides, one of the smallest four-disulfide-constrained plant CRPs, is a new family of CRPs. Additionally, this study provides new insights into the molecular diversity of plant cysteine-rich peptides and the unusual lybatide scaffold could be developed as a useful template for peptide engineering and therapeutic development.