Antifolates inhibit Cryptococcus biofilms and enhance susceptibility of planktonic cells to amphotericin B.

Eur J Clin Microbiol Infect Dis

Department of Pathology and Legal Medicine, School of Medicine, Postgraduate Program in Medical Microbiology and Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, CE, Brazil.

Published: April 2013

The Cryptococcus neoformans species complex contains the most important agents of fungal meningoencephalitis. Therapeutic choices are limited and issues related to toxicity and resistance to antifungals have been described. The present study evaluated the inhibitory effect of the antifolate combinations sulfamethoxazole-trimethoprim (SMX/TMP) and sulfadiazine-pyrimethamine (SDZ/PYR) against planktonic cells and biofilms of C. neoformans and C. gattii. The influence of the antifolate combinations on the amphotericin minimum inhibitory concentration (MIC) of planktonic cells was also investigated. In addition, the effect of these combinations on the cellular ergosterol content of planktonic cells was studied. Strains of C. neoformans (n = 15) and C. gattii (n = 15) obtained from environmental or clinical sources were evaluated by the broth microdilution method. SMX/TMP and SDZ/PYR showed antifungal activity against free living cells and sessile cells of Cryptococcus spp. Moreover, planktonic cells showed increased susceptibility to amphotericin B after pre-incubation with sub-inhibitory concentrations of SMX/TMP or SDZ/PYR. The drug combinations SMX/TMP and SDZ/PYR were able to prevent the biofilm formation and showed inhibitory effect against mature biofilms of both species. Additionally, the study showed that antifolate drugs reduced the ergosterol content in C. neoformans and C. gattii planktonic cells. Our results highlight the antifungal potential of antifolate drugs.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10096-012-1774-8DOI Listing

Publication Analysis

Top Keywords

planktonic cells
24
neoformans gattii
12
smx/tmp sdz/pyr
12
cells
8
antifolate combinations
8
ergosterol content
8
antifolate drugs
8
planktonic
6
antifolates inhibit
4
inhibit cryptococcus
4

Similar Publications

Polydimethylsiloxane loaded capsaicin afflicts membrane integrity, metabolic activity and biofilm formation of nosocomial pathogens.

Microb Pathog

January 2025

Biofouling and Biofilm Processes Section, Water and Steam Chemistry Division, Bhabha Atomic Research Centre Facilities, Kalpakkam 603 102, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094, India. Electronic address:

Biofilms constitute 80% of all nosocomial infections associated with invasive medical devices. Polydimethylsiloxane, a highly elastic, inert, non-reactive, biocompatible silicone polymer is widely used as implant biomaterial due to its non-toxic and low-immunogenic nature. Owing to its hydrophobicity, PDMS suffers from microbial adhesion.

View Article and Find Full Text PDF

Copper(II) oxide nanoparticles (CuO NPs) are used in different industries and agriculture, thus leading to their release to the environment, which raises concerns about their ecotoxicity and biosafety. The main toxicity mechanism of nanometals is oxidative stress as a result of the formation of reactive oxygen species caused by metal ions released from nanoparticles. Bacterial biofilms are more resistant to physical and chemical factors than are planktonic cells due to the extracellular polymeric matrix (EPM), which performs a protective function.

View Article and Find Full Text PDF
Article Synopsis
  • The study explores using lytic bacteriophages combined with the antibiotic linezolid to treat methicillin-resistant bacteria, showing a strong synergistic effect against planktonic cells.
  • A checkerboard assay indicated that a specific combination of low doses of both agents completely inhibited bacterial growth, but the order of treatments affected biofilm cells—sequential treatment was less effective while simultaneous treatment was more beneficial.
  • Transcriptomic analysis revealed that the combination altered bacterial metabolism, including energy and virulence factors, emphasizing the need to optimize treatment strategies for maximum effectiveness against infections.
View Article and Find Full Text PDF

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 PDF

Exploring the potential of hydrolytic enzymes combined with antibacterial agents to disrupt pathogenic biofilms and disinfect released cells.

Biofouling

January 2025

Centro de Investigación en Alimentación y Desarrollo, A.C. (CIAD), Carretera Gustavo Enrique Astiazarán Rosas, Hermosillo, Sonora, México.

Biofilms are bacterial communities encapsulated in a self-produced extracellular polymeric matrix comprising carbohydrates, proteins, lipids, and DNA. This matrix provides structural integrity while significantly enhancing bacterial antibiotic resistance, presenting substantial disinfection challenges. The persistence of biofilm-associated infections and foodborne outbreaks underscores the need for more effective disinfection strategies.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!