The effects of amphotericin B on the interaction of Candida albicans with fibroblast cultures

Sublethal amounts of amphotericin B inhibited the interaction of Candida albicans with cultured fibroblasts. Different C. albicans clinical isolates exhibited varying degrees of sensitivity to the drug, but those isolates that were the most infective in control cultures appeared to be the most resistant to amphotericin B mediated infection inhibition. Although amphotericin B inhibited germ tube formation at the sublethal concentration of 0.3 μg/mL, lower concentrations inhibited infection without preventing germination. The extent of this latter activity varied with the isolate and amphotericin B concentration and appeared to be related to sublethal effects on germinated yeasts. While amphotericin B effectively prevented new fibroblast infection, it did not dissociate those yeasts which had established an infection before its addition.Key words: yeast, Candida, amphotericin B, polyene antibiotics.

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Satureja khuzistanica Jamzad essential oil and its anti-candidal activities against clinical isolates of Candida albicans isolated from women with candidiasis

Infectio ◽

10.22354/in.v23i1.750 ◽

2018 ◽

Vol 23 (1) ◽

pp. 16 ◽

Cited By ~ 1

Author(s):

Mohaddese Mahboubi ◽

Bahareh Attaran

Keyword(s):

Candida Albicans ◽

Essential Oil ◽

Germ Tube ◽

Folk Medicine ◽

Tube Formation ◽

Clinical Isolates ◽

Analgesic Agent ◽

Aerial Parts ◽

Main Component ◽

Cytoplasmic Structures

Satureja khuzistanica Jamzad is known as antiseptic and analgesic agent in folk medicine. The aim of this investigation was to evaluate the anti-candidal activity of S. khuzistanica aerial parts essential oil against clinical isolates of Candida albicans, which were isolated from women with chronic recurrent candidiasis. For this purpose, the chemical composition of hydro-distilled essential oil was determined by GC and GC-MS analysis. Then, the anti-candidal activity of essential oil and its main component (carvacrol) were determined. Carvacrol (94.1%) was the main component of essential oil, followed by β-bisabolene, p-cymene and γ-terpinene. S. khuzistanica essential oil had strong anti-candidal activity against clinical isolates of C. albicans via inhibition of germ tube formation and induction the huge punctures in the cytoplasmic structures. The cell membranes were intact in presence of essential oil or carvacrol. S. khuzistanica essential oil as the main source of carvacrol can be used for treatment of C. albicans related infections.

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Antifungal activity and influence of propolis against germ tube formation as a critical virulence attribute by clinical isolates of Candida albicans

Journal de Mycologie Médicale ◽

10.1016/j.mycmed.2015.11.004 ◽

2016 ◽

Vol 26 (4) ◽

pp. 298-305 ◽

Cited By ~ 18

Author(s):

N.S. Haghdoost ◽

T.Z. Salehi ◽

A. Khosravi ◽

A. Sharifzadeh

Keyword(s):

Candida Albicans ◽

Antifungal Activity ◽

Germ Tube ◽

Tube Formation ◽

Clinical Isolates ◽

Virulence Attribute

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Susceptibility of Fluconazole-Resistant Candida albicans to Thyme Essential Oil

Microorganisms ◽

10.3390/microorganisms9122454 ◽

2021 ◽

Vol 9 (12) ◽

pp. 2454

Author(s):

Najla A Alshaikh ◽

Kahkashan Perveen

Keyword(s):

Candida Albicans ◽

Essential Oil ◽

Germ Tube ◽

Tube Formation ◽

Clinical Isolates ◽

Military Hospital ◽

Thymus Vulgaris ◽

Drug Resistant ◽

Thyme Essential Oil ◽

Fluconazole Resistant

Candida spp. is the most common microbial pathogen in fungal infections. There has been a tremendous increase in cases of candidiasis, especially among critically ill non-neutropenic patients. Candida albicans’ isolates were procured from the Prince Sultan Military Hospital, Riyadh, KSA. The isolates were characterized for their identification using CHROMagar, carbohydrate metabolism, germ tube formation, and RAPD-PCR techniques. The essential oil of Thymus vulgaris was obtained by hydro-distillation and characterized to decipher the major bioactive phytoconstituents. The antifungal activity of the thyme essential oil (TEO) was evaluated against fluconazole-resistant C. albicans isolates. The major phytocomponents identified by GC/MS were thymol (68.1%) followed by γ-terpinene (8.9%), cymol (7.7%), caryophyllene (1.1%), linalool (1.4%). The TEO successfully reduced the growth of C. albicans isolates. At very low doses, the TEO proved to be fungi static and fungicidal. TEO also effectively inhibited the germ tube formation and budging of fungal pathogens. The time kill assays have shown that TEO was more effective against drug resistant clinical isolates than fluconazole. This study provides an array of experimental evidence regarding the therapeutic efficacy of TEO against the drug-resistant clinical isolates of C. albicans. The findings may be used in the development of a new antifungal agent accordingly.

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Amphotericin B resistance leads to enhanced proteinase and phospholipase activity and reduced germ tube formation in Candida albicans

Fungal Biology ◽

10.1016/j.funbio.2009.12.003 ◽

2010 ◽

Vol 114 (2-3) ◽

pp. 189-197 ◽

Cited By ~ 17

Author(s):

Rohitashw Kumar ◽

P.K. Shukla

Keyword(s):

Candida Albicans ◽

Amphotericin B ◽

Germ Tube ◽

Tube Formation ◽

Phospholipase Activity

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CAP1, an Adenylate Cyclase-Associated Protein Gene, Regulates Bud-Hypha Transitions, Filamentous Growth, and Cyclic AMP Levels and Is Required for Virulence of Candida albicans

Journal of Bacteriology ◽

10.1128/jb.183.10.3211-3223.2001 ◽

2001 ◽

Vol 183 (10) ◽

pp. 3211-3223 ◽

Cited By ~ 118

Author(s):

Yong-Sun Bahn ◽

Paula Sundstrom

Keyword(s):

Candida Albicans ◽

Cyclic Amp ◽

Adenylate Cyclase ◽

Germ Tube ◽

Filamentous Growth ◽

Tube Formation ◽

Camp Signaling ◽

Solid Media ◽

Opportunistic Fungal Pathogen ◽

Camp Levels

ABSTRACT In response to a wide variety of environmental stimuli, the opportunistic fungal pathogen Candida albicans exits the budding cycle, producing germ tubes and hyphae concomitant with expression of virulence genes, such as that encoding hyphal wall protein 1 (HWP1). Biochemical studies implicate cyclic AMP (cAMP) increases in promoting bud-hypha transitions, but genetic evidence relating genes that control cAMP levels to bud-hypha transitions has not been reported. Adenylate cyclase-associated proteins (CAPs) of nonpathogenic fungi interact with Ras and adenylate cyclase to increase cAMP levels under specific environmental conditions. To initiate studies on the relationship between cAMP signaling and bud-hypha transitions in C. albicans, we identified, cloned, characterized, and disrupted the C. albicans CAP1 gene. C. albicans strains with inactivated CAP1 budded in conditions that led to germ tube formation in isogenic strains withCAP1. The addition of 10 mM cAMP and dibutyryl cAMP promoted bud-hypha transitions and filamentous growth in thecap1/cap1 mutant in liquid and solid media, respectively, showing clearly that cAMP promotes hypha formation in C. albicans. Increases in cytoplasmic cAMP preceding germ tube emergence in strains having CAP1 were markedly diminished in the budding cap1/cap1 mutant. C. albicans strains with deletions of both alleles ofCAP1 were avirulent in a mouse model of systemic candidiasis. The avirulence of a germ tube-deficientcap1/cap1 mutant coupled with the role of Cap1 in regulating cAMP levels shows that the Cap1-mediated cAMP signaling pathway is required for bud-hypha transitions, filamentous growth, and the pathogenesis of candidiasis.

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