Cyclic α-maltosyl-(1→6)-maltose (CMM) is a cyclic glucotetrasaccharide with alternating α-1,4 and α-1,6 linkages. Here, we report functional and structural analyses on CMM-binding protein (CMMBP), which is a substrate-binding protein (SBP) of an ABC importer system of the bacteria Arthrobacter globiformis. Isothermal titration calorimetry analysis revealed that CMMBP specifically bound to CMM with a Kd value of 9.6 nM. The crystal structure of CMMBP was determined at a resolution of 1.47 Å, and a panose molecule was bound in a cleft between two domains. To delineate its structural features, the crystal structure of CMMBP was compared with other SBPs specific for carbohydrates, such as cyclic α-nigerosyl-(1→6)-nigerose and cyclodextrins. These results indicate that A. globiformis has a unique metabolic pathway specialized for CMM.
G protein-coupled estrogen receptor 1 (GPER1) plays a crucial role in the progression of breast cancer and has emerged as a promising therapeutic target. However, while missense mutations in GPER1 have been detected in breast invasive carcinoma (BIC) samples, the resulting molecular, cellular and pharmacological changes remain unclear. The present study categorized BIC samples from The Cancer Genome Atlas database based on mutation information available in the cBioPortal database.
Self-assembling cyclic peptide nanotubes are fascinating supramolecular systems with promising potential for various applications, such as drug delivery, transmembrane ionic channels, and artificial light-harvesting systems. In this study, we present novel pH-responsive nanotubes based on asymmetric cyclic peptide-polymer conjugates. The pH response is introduced by a tertiary amine-based polymer, poly(dimethylamino ethyl methacrylate) (pDMAEMA) or poly(diethylamino ethyl methacrylate) (pDEAEMA) which is protonated at low pH.
Sulfonium is an electrophilic and biocompatible group that is widely applied in synthetic chemistry on small molecules. However, there have been few developments of peptide or protein-based sulfonium tools. We recently reported sulfonium-mediated tryptophan crosslinking and developed NleSme2 (norleucine-dimethylsulfonium) peptides as dimethyllysine mimics that crosslink site-specific methyllysine readers.
The dynamic behavior of articular cartilage (a soft porous biological tissue) with strain-dependent nonlinear permeability under cyclic compressive loading and magnetic field is investigated computationally. The compressive force is applied on top surface of the cylindrical plug of the tissue by means of a porous filter. The study of mechanical and deformational behavior of soft porous tissues such as articular cartilage under dynamic compressive loading and magnetic field is useful in understanding the underlying mechano-biological process that may lead to the development of a treatment and recovery protocol in a diseased state.
Mechanical ventilation (MV) remains a cornerstone of critical care; however, its prolonged application can exacerbate lung injury, leading to ventilator-induced lung injury (VILI). Although previous studies have implicated ferroptosis in the pathogenesis of VILI, the underlying mechanisms remain unclear. This study investigated the roles of ferritinophagy in ferroptosis subsequent to VILI.
