Antifungal activity of biosynthesized silver nanoparticles from Candida albicans on the strain lacking the CNP41 gene

Darshan Dhabalia,M Anaul Kabir,Shareefraza J Ukkund,Usman Taqui Syed,Wasim Uddin

doi:10.1088/2053-1591/abcc83

Abstract

The upsurge of immunocompromised patients has led to extensive study of fungal infections with Candida albicans being the frontline model of pathogenic yeast in humans. In the quest to find novel antifungal agents, this study reports the potential usage of wild-type C. albicans strain C86 to biosynthesise silver nanoparticles by microwave assisted technique. Visual colour change and UV-spectrophotometer were used for primary detection of silver nanoparticles. Additionally, the FTIR peaks confirm the particles’ formation and surface characterisation techniques such as FESEM and EDX suggests that the silver nanoparticles were sized in the range of 30–70 nm. Furthermore, pioneering work of homologous recombination technique was systematically employed to delete uncharacterized gene orf19.3120 (CNP41) in the C86 strain creating the deletion strain C403 of C. albicans. To amalgamate the two significant findings, biosynthesized silver nanoparticles were subjected to antifungal studies by disk diffusion assay on the strain C403 that lacks the gene orf19.3120 (CNP41) of C. albicans. As a synergetic approach, combinational effect was studied by incorporating antifungal drug fluconazole. Both individual and enhanced combinational antifungal effects of silver nanoparticles and fluconazole were observed on genetically modified C403 strain with 40% increase in fold area compared to wild-type C86 strain. This can be attributed to the synergetic effect of the bonding reaction between fluconazole and AgNPs. Taken together, this first-ever interdisciplinary study strongly suggests that the CNP41 gene could play a vital role in drug resistance in this fungal pathogen.

Highlights

Diverse populations of microbes like bacteria and fungi have advertently inhabited the human race with the passage of time
Deletion of CNP41 gene in Candida albicans The Candida albicans strain C86 was transformed with the plasmid pKA244 by digesting with SacI/HindIII and ura+ transformants were obtained on plate lacking uridine
15 ura+ transformants were screened by this process and 3 right candidates were obtained for first copy deletion of CNP41 gene

Summary

Introduction

Diverse populations of microbes like bacteria and fungi have advertently inhabited the human race with the passage of time. With increase in the number of immunocompromised patients, the study of fungal infections has gained more prominence in medical research with Candida albicans being one of the frontline model of pathogenic yeast in humans [1]. In the last few decades, several antifungal drugs have been developed to treat Candida infections Based on their chemical composition and mode of action, antifungals have been classified into different groups such as allylamines, azoles, echinocandins, 5-fluorocytosine and polyenes [5]. Among these groups, azole class of antifungals are preferred due to its broad spectrum activity, high efficacy and low toxicity. To overcome the current challenges witnessed in the existing conventional antifungal agents, the present work addresses the dire need to explore a novel antifungal agent which would be cost-effective with lesser side effects

Methods

Results

Conclusion