Candida tropicalis morphotypes show altered cellular structure and gene expression pre- and post-exposure to fluconazole.

A feature of Candida tropicalis is its ability to undergo phenotypic switching that can affect antifungal sensitivity and virulence traits. Here, we investigated the effect of switching on alterations at the cellular structure level of C. tropicalis morphotypes and whether exposure to fluconazole (FLC) in vitro could be associated with these alterations in a morphotype-dependent manner.

Altered phagocytosis and morphogenesis of phenotypic switching-derived strains of the pathogenic Candida tropicalis co-cultured with phagocytic cells.

Background And Objective: Candida tropicalis is among the most prevalent human pathogenic yeast species. Switch states of C. tropicalis differ in virulence traits.

Adhesion and biofilm formation by the opportunistic pathogen : what do we know?

 is among the most important  species in terms of epidemiology, virulence and resistance. Considering the increase in incidence and high rates of mortality associated with this species, knowledge of its adhesion and biofilm formation abilities is needed. These traits determine the persistence and survival of yeast on different indwelling medical devices and host sites.

Antibacterial efficacy of microencapsulated bacteriocin on and .

This study focused on the microencapsulation of enterocin from ( MF5) in whey powder (WP) using a spray-drying technique followed by the evaluation of how complexation can preserve the enterocin structure and antimicrobial activity against food-borne pathogens. Crude enterocin samples (1 and 5%) were microencapsulated in 10% WP. The antimicrobial activity of unencapsulated (crude) enterocin and microencapsulated enterocin was tested against the target bacteria Typhimurium, , , , and .

Deciphering Colonies of Phenotypic Switching-Derived Morphotypes of the Pathogenic Yeast Candida tropicalis.

Background: Phenotypic switching generates fungal colonies with altered morphology and allows pathogens to adapt to changing environments.

Objective: This study investigated the structure and genetic factors of switched morphotypes colonies in Candida tropicalis.

Methods: Morphotypes of C.

Changes in Adhesion of Candida tropicalis Clinical Isolates Exhibiting Switch Phenotypes to Polystyrene and HeLa Cells.

Background: Candida tropicalis is an important human pathogen that can undergo multiple forms of phenotypic switching.

Aim: We aimed to evaluate the effect of phenotypic switching on the adhesion ability of C. tropicalis.

Effect of phenotypic switching on biofilm traits in Candida tropicalis.

Candida tropicalis can undergo multiple forms of phenotypic switching. We have reported a switching system in C. tropicalis that is associated with changes in virulence attributes.

Antimicrobial activity of enterocins against Listeria sp. and other food spoilage bacteria.

Objective: To determine bacteriocin producers and the prevalence of structural enterocin genes and to detect the spectrum of activity against foodborne pathogens, from isolates of Enterococcus faecium and Enterococcus faecalis that were isolated from food and the environment.

Results: The entA, entB, entP, ent1071 and entX genes, which encode enterocins were the most frequently observed. Enterocins were thermostable, proteinaceous, and resistant to catalase.

Phenotypic switching in Candida tropicalis alters host-pathogen interactions in a Galleria mellonella infection model.

Candida tropicalis is a human pathogen associated with high mortality rates. We have reported a switching system in C. tropicalis consisting of five morphotypes - the parental, switch variant (crepe and rough), and revertant (crepe and rough) strains, which exhibited altered virulence in a Galleria mellonella model.

Assessment of vancomycin resistance transfer among enterococci of clinical importance in milk matrix.

Dissemination of vancomycin resistance in enterococci has been associated with horizontal transfer of mobile genetic elements. Aim of the study was to evaluate if milk matrix is a suitable environment to support transferability of vancomycin resistance (A) gene from clinical vancomycin-resistant to vancomycin-sensitive . Enterococci strains were firstly screened for the presence of (inducible sex pheromone determinant) gene, A and L genes (vancomycin and tetracycline resistance markers, respectively) and the E (extracellular metalloendopeptidase) gene to define the mating pairs.

Inhibitory effect of bacteriocins from enterococci on developing and preformed biofilms of Listeria monocytogenes, Listeria ivanovii and Listeria innocua.

The biofilm-forming ability of Listeria spp. is a concern to the food industry and health sectors. The aim of this study was to verify the inhibitory activity of bacteriocins produced by enterococci (Enterococcus faecium 20, 22 and 24 and Enterococcus faecalis 27) on developing biofilm and preformed biofilm of Listeria species.

Biofilm formation by blood isolates of Candida parapsilosis sensu stricto in the presence of a hyperglycidic solution at comparable concentrations of total parenteral nutrition.

Introduction: Administration of total parenteral nutrition (TPN) via catheters increases the risk for candidemia from Candida parapsilosis.

Methods: C. parapsilosis sensu stricto blood isolates were evaluated for ability total biomass biofilm formation and morphogenesis in presence of glucose at TPN equivalent concentrations.

Antifungal activity of silver nanoparticles and simvastatin against toxigenic species of Aspergillus.

Aspergillus spp. are ubiquitous fungi that grow on stored grains. Some species produce toxins that can harm human and animal health, leading to hepato- and nephrotoxicity, immunosuppression and carcinogenicity.

How much do we know about hemolytic capability of pathogenic Candida species?

Hemolytic factor production by pathogenic Candida species is considered an important attribute in promoting survival within the mammal host through the ability to assimilate iron from the hemoglobin-heme group. Hemolytic capability has been evaluated for Candida species based on hemolysis zones on plate assay, analysis of hemolytic activity in liquid culture medium, and hemolysis from cell-free culture broth. The production of hemolytic factor is variable among Candida species, where C.

γ-irradiation from radiotherapy improves the virulence potential of Candida tropicalis.

Aim: To evaluate if radiation used in radiotherapy can cause changes in the virulence potential of Candida tropicalis ATCC 750.

Materials & Methods: C. tropicalis was exposed in vitro to identical dose and scheme of irradiation would be used in patients with head and neck cancer.

Hemolytic capability and expression of a putative haem oxygenase-encoding gene by blood isolates of Candida tropicalis are influenced by iron deprivation and the presence of hemoglobin and erythrocytes.

Although hemolytic activity is known to be a putative virulence factor contributing to candidal pathogenesis, its production by Candida tropicalis, a species closely related to Candida albicans, is poor understood. The present study was undertaken to evaluate the hemolytic activity and the expression level of a putative haem oxygenase encoding gene by blood isolates of C. tropicalis following growth in iron deprivation, and in the presence of hemoglobin and erythrocytes.

Screening of the Enterocin-Encoding Genes and Antimicrobial Activity in Enterococcus Species.

In the current study, a total of 135 enterococci strains from different sources were screened for the presence of the enterocin-encoding genes entA, entP, entB, entL50A, and entL50B. The enterocin genes were present at different frequencies, with entA occurring the most frequently, followed by entP and entB; entL50A and L50B were not detected. The occurrence of single enterocin genes was higher than the occurrence of multiple enterocin gene combinations.

Tenebrio molitor (Coleoptera: Tenebrionidae) as an alternative host to study fungal infections.

Models of host–pathogen interactions are crucial for the analysis of microbial pathogenesis. In this context, invertebrate hosts, including Drosophila melanogaster (fruit fly), Caenorhabditis elegans (nematode) and Galleria mellonella (moth), have been used to study the pathogenesis of fungi and bacteria. Each of these organisms offers distinct benefits in elucidating host–pathogen interactions.

Effects of human blood red cells on the haemolytic capability of clinical isolates of Candida tropicalis.

Background: Candida tropicalis is an increasingly important human pathogen associated with high mortality rates; however, little is known regarding the virulence properties of C. tropicalis, particularly the production of haemolytic factor. Although Candida spp may acquire iron from human blood red cells (RBCs) by producing a haemolytic factor that promotes cell lyses, at present there are no data regarding the effect of RBCs on the production of haemolytic molecules.

Nosocomial bloodstream Candida infections in a tertiary-care hospital in South Brazil: a 4-year survey.

The aims of this study were to evaluate the epidemiology of nosocomial candidemia in a tertiary hospital in South Brazil and the in vitro antifungal susceptibility of isolates. Blood strains from 108 patients were identified by PCR-based method. Some 30.

Comparison between automated system and PCR-based method for identification and antimicrobial susceptibility profile of clinical Enterococcus spp.

Enterococci are increasingly responsible for nosocomial infections worldwide. This study was undertaken to compare the identification and susceptibility profile using an automated MicrosScan system, PCR-based assay and disk diffusion assay of Enterococcus spp. We evaluated 30 clinical isolates of Enterococcus spp.

Hemolytic factor production by clinical isolates of Candida species.

Most cases of fungal bloodstream infections (BIs) are attributed to Candida albicans; however, non-Candida albicans Candida species have recently been identified as common pathogens. Although hemolytic factor is known to be putative virulence factor contributing to pathogenicity in Candida species, its production is poorly evaluated. The present study was undertaken to analyze the production of hemolytic factor by C.

Phenotypic switching in Candida tropicalis: association with modification of putative virulence attributes and antifungal drug sensitivity.

Although Candida tropicalis has become an increasingly important human pathogen, little is known regarding its potential to cause disease. In this study we evaluated the phenotypic switching ability of C. tropicalis and analyzed the effect of switching on biological properties related to virulence factors.