Penicillin-binding proteins (PBPs) are enzymes involved in the assembly of the bacterial cell wall, a major target for antibiotics. These proteins are classified by mass into high-molecular-weight PBPs, which are transpeptidases that form peptidoglycan cross-links, and low-molecular-weight PBPs, which are typically hydrolases. We report a functionally unique family of low-molecular-weight PBPs that act as transpeptidases rather than hydrolases, but they do not cross-link peptidoglycan. We show that these PBPs can exchange d-amino acids bearing chemical tags or affinity handles into peptidoglycan precursors, including Lipid II, enabling biochemical studies of proteins involved in cell wall assembly. We report that, in two organisms, the PBPs incorporate lysine into cellular peptidoglycan and that, further, the PBPs have the unprecedented ability to transfer the primary ε-amine of lysine to peptidoglycan.
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http://dx.doi.org/10.1021/jacs.7b10170 | DOI Listing |
Sleep
January 2025
UR2NF-Neuropsychology and Functional Neuroimaging Research Unit affiliated at CRCN - Centre for Research in Cognition and Neurosciences and UNI - ULB Neuroscience Institute, Université Libre de Bruxelles (ULB), Brussels, Belgium.
Enhancing the retention of recent memory traces through sleep reactivation is possible via Targeted Memory Reactivation (TMR), involving cueing learned material during post-training sleep. Evidence indicates detectable short-term microstructural changes in the brain within an hour after motor sequence learning, and post-training sleep is believed to contribute to the consolidation of these motor memories, potentially leading to enduring microstructural changes. In this study, we explored how TMR during post-training sleep affects performance gains and delayed microstructural remodeling, using both standard Diffusion Tensor Imaging (DTI) and advanced Neurite Orientation Dispersion & Density Imaging (NODDI).
View Article and Find Full Text PDFNeuroinformatics
January 2025
Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, 760 Westwood Plaza, Los Angeles, CA, 90024, USA.
A reader of the peer-reviewed neuroscience literature will often encounter expressions like the following: 'the brain is a dynamic system', 'the brain is a complex network', or 'the brain is a highly metabolic organ'. These expressions attempt to define the essential functions and properties of the mammalian or human brain in a simple phrase or sentence, sometimes using metaphors or analogies. We sought to survey the most common phrases of the form 'the brain is…' in the biomedical literature to provide insights into current conceptualizations of the brain.
View Article and Find Full Text PDFInflamm Res
January 2025
Laboratório de Virologia Básica E Aplicada, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais-UFMG, Belo Horizonte, MG, Brazil.
Introduction: The present study aimed at evaluating the systemic profile and network connectivity of immune mediators during acute chikungunya fever (CHIKF) according to days of symptoms onset and ageing.
Methods: A total of 161 volunteers (76 CHIKF patients and 85 non-infected healthy controls) were enrolled.
Results And Discussion: Data demonstrated that a massive and polyfunctional storm of serum immune mediators was observed in CHIKF.
Cell Biol Toxicol
January 2025
Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District, Shenyang , Liaoning Province, China.
NFKB1, a core transcription factor critical in various biological process (BP), is increasingly studied for its role in tumors. This research combines literature reviews, meta-analyses, and bioinformatics to systematically explore NFKB1's involvement in tumor initiation and progression. A unique focus is placed on the NFKB1-94 ATTG promoter polymorphism, highlighting its association with cancer risk across diverse genetic models and ethnic groups, alongside comprehensive analysis of pan-cancer expression patterns and drug sensitivity.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Energy Engineering, Hanyang University, Seoul 04763, Republic of Korea.
Lithium-tellurium (Li-Te) batteries are gaining attention as a promising next-generation energy storage system due to their superior electrical conductivity and high volumetric capacity compared to sulfur and selenium. Tellurium's unique properties, such as suitable redox potential, excellent conductivity, high volumetric capacity, and greatest stability, position it as a strong candidate for negative electrode materials. This study explores the potential of metal tellurides, specifically CuTe and FeTe monolayers, as effective tellurium host materials, leveraging their polar interactions with lithium polytellurides.
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