Production of β-lactamases is the primary mechanism of antibiotic resistance employed by gram-negative pathogens. Chromogenic β-lactams are important reagents for detection and assay of β-lactamases, but limited commercial availability and exorbitant pricing of these compounds are prohibitive. Here we describe a straightforward synthesis of a chromogenic cephalosporin for β-lactamase assay that gives an overall yield of 74%. On hydrolysis, its λ(max) undergoes a bathochromic shift that is easy to see and measure spectrophotometrically with a Δε(442 nm) of 14,500 cm⁻¹ M⁻¹. This compound was shown to be a substrate for a variety of β-lactamases.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ab.2012.06.006 | DOI Listing |
Lasers Surg Med
September 2024
Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Objective: In this study, we evaluated the effectiveness of antimicrobial blue light (aBL; 410 nm wavelength) against β-lactamase-carrying bacteria and the effect of aBL on the activity of β-lactamases.
Methods: Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae strains carrying β-lactamases as well as a purified β-lactamase enzymes were studied. β-lactamase activity was assessed using a chromogenic cephalosporin hydrolysis assay.
Bioorg Chem
September 2024
Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain. Electronic address:
β-Lactamases are bacterial enzymes that inactivate β-lactam antibiotics and, as such, are the most prevalent cause of antibiotic resistance in Gram-negative bacteria. The ever-increasing production and worldwide dissemination of bacterial strains producing carbapenemases is currently a global health concern. These enzymes catalyze the hydrolysis of carbapenems - the β-lactam antibiotics with the broadest spectrum of activity that are often considered as drugs of last resort.
View Article and Find Full Text PDFAntibiotics (Basel)
May 2024
Departamento de Moléstias Infecciosas e Parasitárias, Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, São Paulo 05403-000, Brazil.
Background: Assessing the risk of multidrug-resistant colonization and infections is pivotal for optimizing empirical therapy in hematopoietic stem cell transplants (HSCTs). Limited data exist on extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) colonization in this population. This study aimed to assess whether ESBL-E colonization constitutes a risk factor for ESBL-E bloodstream infection (BSI) and to evaluate ESBL-E colonization in HSCT recipients.
View Article and Find Full Text PDFJ Microbiol Immunol Infect
June 2024
Unit of Microbiology and Clinical Microbiology, Department of Clinical-Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Italy. Electronic address:
Lett Appl Microbiol
April 2024
Institute of Environmental Science and Research (ESR), Christchurch Science Centre, 27 Creyke Road, Ilam, Christchurch 8041, New Zealand.
Diagnostic laboratories in Aotearoa, New Zealand (NZ) refer cultures from faecal samples positive for Shiga toxin genes to the national Enteric Reference Laboratory for isolation of Shiga toxin-producing Escherichia coli (STEC) for epidemiological typing. As there was variation in the culture media being referred, a panel of 75 clinical isolates of STEC, representing 28 different serotypes, was used to assess six commercially available media and provide guidance to clinical laboratories. Recommendations were subsequently tested for a 3-month period, where STEC isolations and confirmations were assessed by whole genome sequencing analysis against the culture media referred.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!