Proteolytic proteins solubilized from the membrane of Bacillus intermedius were studied by electrophoresis. The content of membrane-bound proteinases was lower in cells grown in the presence of glucose. Proteinase enzymograms revealed four molecular forms of subtilisin and four molecular forms of glutamyl endopeptidase. The electrophoretic mobility of one of the molecular forms was similar to those of the mature extracellular proteinases. Chromatography of membrane proteins on a MonoS column yielded four protein fractions that caused hydrolysis of Z-Glu-pNA and four fractions that caused hydrolysis of Z-Ala-Ala-Leu-pNA, which is in agreement with the results of electrophoresis. The molecular forms of proteinases identified in the membrane may reflect various stages of biogenesis of the corresponding extracellular enzymes.
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JBJS Case Connect
October 2024
Department of Orthopaedic Surgery, The University of Tokyo Hospital, Bunkyo-ku, Tokyo, Japan.
Case: An 18-year-old woman presented with shoulder pain that had persisted for a year. The magnetic resonance imaging showed a solitary lesion in the subacromial bursa (SAB). Arthroscopy revealed an ovoid mass connected to the bursal wall with thin synovial tissue that was excised en bloc arthroscopically.
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January 2025
Engineering Research Center of Advanced Rare Earth Materials (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China.
Hierarchical structures are essential in natural adhesion systems. Replicating these in synthetic adhesives is challenging due to intricate molecular mechanisms and multiscale processes. Here, we report three phosphorylated peptides featuring a hydrophobic self-assembly motif linked to a hydrophilic phosphorylated sequence (pSGSS), forming peptide fibril nanoframeworks.
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School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia.
Innate immunity relies on Toll-like receptors (TLRs) to detect pathogen-associated molecular patterns. The TIR (Toll/interleukin-1 receptor) domain-containing TLR adaptors TRIF (TIR domain-containing adaptor-inducing interferon-β) and TRAM (TRIF-related adaptor molecule) are essential for MyD88-independent TLR signaling. However, the structural basis of TRIF and TRAM TIR domain-based signaling remains unclear.
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January 2025
Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104.
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Shiyan Key Laboratory of Quantum Information and Precision Optics, and School of Mathematics, Physics and Optoelectronic Engineering, Hubei University of Automotive Technology, Shiyan 442002, People's Republic of China.
The molecular energy transfer is crucial for many different physicochemical processes. The efficiency of traditional resonance energy transfer relies on dipole-dipole distance between molecules and becomes negligible when the distance is larger than ∼10 nm, which is difficult to overcome. Cavity polariton, formed when placing molecules inside the cavity, is a promising way to surmount the distance limit.
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