The activity of telavancin was compared with vancomycin against methicillin-resistant Staphylococcus aureus (MRSA) in planktonic culture and biofilms grown using a range of in vitro models. Antibiotic efficacy was determined using 24 clinical isolates, including healthcare-associated (HA)-MRSA, community-associated (CA)-MRSA and isolates with reduced (intermediate) susceptibility to vancomycin (VISA). Activity against biofilms was compared using three models: 96-peg plates, 96-well flat-bottom plates and a flow-cell system. Cell death was evaluated using a metabolic dye and Live/Dead staining. The planktonic minimum inhibitory concentration (MIC) range for telavancin was lower than that for vancomycin (0.06-0.25 mg/l and 0.5-8 mg/l, respectively). Vancomycin (100 × MIC) killed, on average, 59% of cells in HA-MRSA biofilms grown on 96-peg plates, 44% of cells in CA-MRSA biofilms and 26% of cells in VISA biofilms. Telavancin (100 × MIC) killed, on average, 63%, 49% and 41% of cells, respectively. The antibiotics showed similar efficacy against MRSA biofilms but telavancin was more effective against those formed by VISA isolates. In the flow-cell system, antibiotic cell killing was enhanced with both antibiotics, killing up to 80% of biofilm-associated cells. The variance in cell killing displayed when biofilms were grown using different systems highlights the importance of selecting an appropriate model for antimicrobial efficacy tests. The flow-cell system more closely reflects conditions encountered during infection and is possibly more clinically relevant than a 96-well plate system. Despite differences between the models evaluated, telavancin typically demonstrated improved efficacy over vancomycin, indicating the potential value of the agent in the treatment of biofilm-mediated infections caused by S. aureus, especially multidrug-resistant isolates.
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http://dx.doi.org/10.1007/s10096-013-1883-z | DOI Listing |
J Environ Manage
January 2025
Department of Chemical & Biomolecular Engineering, Institute for Corrosion and Multiphase Technology, Ohio University, Athens, 45701, USA; Department of Biological Sciences, Molecular & Cellular Biology Program, Ohio University, Athens, OH, 45701, USA. Electronic address:
Biofilms can cause biofouling, water quality deterioration, and transmission of infectious diseases. They are also responsible for microbiologically influenced corrosion (MIC) which can cause leaks, resulting in environmental disasters. A new disposable biofilm/MIC test kit was demonstrated to distinguish abiotic corrosion of carbon steel from MIC.
View Article and Find Full Text PDFJ Photochem Photobiol B
January 2025
Department of Ophthalmology, Aotearoa New Zealand National Eye Centre, The University of Auckland, Auckland, New Zealand. Electronic address:
Purpose: Preclinical studies have confirmed the safety and efficacy of narrowband low-intensity ultraviolet C light (UVC) in managing bacterial corneal infection. To further consolidate these findings, the present study aimed to explore in vitro anti-biofilm efficacy of low-intensity UVC light for its potential use in biofilm-related infections.
Methods: Pseudomonas aeruginosa biofilm was grown in chamber well slides for 48 h and exposed to one of the following challenges: UVC (265 nm wavelength, intensity 1.
Microorganisms
December 2024
Centre of Biological Engineering, LIBRO-Laboratório de Investigação em Biofilmes Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
is a major cause of chronic respiratory infections in patients with cystic fibrosis (CF), with biofilm formation contributing to its persistence and antibiotic resistance. This study aimed to gain insights into the mechanistic action of succinic acid as a ciprofloxacin adjuvant against clinically relevant CF isolates, including small colony variants and mucoid strains, and a ciprofloxacin-resistant strain grown within CF dense mucus. Time-kill assays in artificial CF mucus, along with planktonic and surface-attached biofilm experiments, were used to assess the activity of succinic acid alone and in combination with sublethal ciprofloxacin concentrations.
View Article and Find Full Text PDFBiofilm
June 2025
Infectious Bacterial Diseases Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, IA, USA.
The genus comprises unique atypical spirochete bacteria that includes the etiological agent of leptospirosis, a globally important zoonosis. Biofilms are microecosystems composed of microorganisms embedded in a self-produced matrix that offers protection against hostile factors. Leptospires form biofilms in rice fields and unsanitary urban areas, and while colonizing rodent kidneys.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Biomedical Sciences, Carlton College of Veterinary Medicine, Oregon State University, Corvallis, USA.
In the past 20 years infections caused by Mycobacterioides abscessus have become increasingly common in patients with chronic lung conditions. The microorganisms are also resistant to a number of antibiotic classes, making treatment challenging. To begin understanding how the bacterium adapts to the lung environment, pure colonies of M.
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