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A fraction of methicillin-resistant Staphylococcus aureus (MRSA) shows resistance to vancomycin (VCM) in the presence of β-lactam antibiotics (BIVR) at low concentrations. We hypothesized that the BIVR phenomenon might be exerted by a peptidoglycan derivative(s) generated as a consequence of β-lactam antibiotic action. To verify this hypothesis, we isolated the fraction that mimicked the effect of β-lactam antibiotics by the enzymatic treatment of the crude cell wall. The active components were purified by a combination of reverse phase chromatographies, mass spectrum and amino-acid analyses, and were identified to be a muropeptide with the following formula: N-acetyglucosamyl-N-acetylmuramyl--Ala-D-isoGln-L-Lys-(ɛ-NH-4Gly)-D-Ala-2Gly. This is the very first identification of the active component, which induces VCM resistance in MRSA. We found that the BIVR cells are highly sensitive to this compound rendering the cells resistant to VCM compared with non-BIVR MRSA.
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http://dx.doi.org/10.1038/ja.2010.75 | DOI Listing |
Genes Dev
September 2025
Department of Biological Sciences, Columbia University, New York, New York 10027, USA;
Enhancer RNAs (eRNAs) are transcribed by during enhancer activation but are typically rapidly degraded in the nucleus. During states of reduced RNA surveillance, however, eRNAs and other similar "noncoding" RNAs (including, e.g.
View Article and Find Full Text PDFAppl Clin Inform
September 2025
Pediatric Critical Care, Stanford University School of Medicine, Stanford, United States.
Background: Time spent in the electronic health record (EHR) is an important measure of clinical activity. Vendor-derived EHR use metrics may not correspond to actual EHR experience. Raw EHR audit logs enable customized EHR use metrics, but translating discrete timestamps to time intervals is challenging.
View Article and Find Full Text PDFBioorg Med Chem Lett
September 2025
Galapagos SASU, 102 avenue Gaston Roussel, 93230 Romainville, France. Electronic address:
The salt-inducible kinase (SIK) family encompasses three isoforms, SIK1, SIK2, and SIK3, which are members of the AMP-activated protein kinase (AMPK) family of serine/threonine protein kinases. SIK inhibition has emerged as a potential therapeutic approach across multiple indications, as SIKs regulate a diverse set of physiological processes such as metabolism, bone remodeling, immune response, malignancies, skin pigmentation, and circadian rhythm. Within isoform-specific SIK inhibitors there is a need to understand the distinct role of each protein, and here we describe the first SIK1 selective inhibitors.
View Article and Find Full Text PDFArch Biochem Biophys
September 2025
Department of Chemistry and Biochemistry, Howard College of Arts and Sciences, Samford University, 800 Lakeshore Drive, Birmingham, AL, USA, 35229. Electronic address:
Tetrahydrodipicolinate N-succinyltransferase (DapD) catalyzes the reaction of tetrahydrodipicolinate (THDP) and succinyl-CoA to form (S)-2-(3-carboxypropanamido)-6-oxoheptanedioic acid and coenzyme A. The enzyme is in the diaminopimelate-lysine biosynthesis pathway which produces two metabolites necessary for the survival and growth of pathogenic bacteria. Since lysine is an essential amino acid to humans, DapD is a potentially safe target for antibiotic therapies.
View Article and Find Full Text PDFNeurobiol Dis
September 2025
F.M. Kirby Neurobiology Department, Boston Children's Hospital, Boston, MA, USA; Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; Human Neuron Core, Rosamund Stone Zander Translational Neuroscience Center, Boston Children's Hospital, Boston, MA, USA.
CDKL5 deficiency disorder (CDD) is a rare developmental and epileptic encephalopathy resulting from variants in cyclin-dependent kinase-like 5 (CDKL5) that lead to impaired kinase activity or loss of function. CDD is one of the most common genetic etiologies identified in epilepsy cohorts. To study how CDKL5 variants impact human neuronal activity, gene expression and morphology, CDD patient-derived induced pluripotent stem cells and their isogenic controls were differentiated into excitatory neurons using either an NGN2 induction protocol or a guided cortical organoid differentiation.
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