Abstract
Among all the essential micronutrients, iron plays an important role in mammalian biology. It is also essential for pathogens infecting mammalian hosts, including bacteria, fungi, and protozoans. As the availability of accessible iron is limited within the mammalian host, several human-pathogenic fungal pathogens, such as Candida albicans, Cryptococcus neoformans, Candida glabrata, and Aspergillus fumigatus, have developed various iron uptake mechanisms. Although Candida parapsilosis is the second or third most common non-albicans Candida species associated with systemic and superficial Candida infections in immunocompromised patients, the mechanisms of iron uptake and homoeostasis remain unknown in this fungus. In the current report, we show that a homologue of the multicopper oxidase gene FET3 is present in the genome of C. parapsilosis (CPAR2_603600) and plays a significant role in iron acquisition. We found that homozygous deletion mutants of CPAR2_603600 showed defects under low-iron conditions and were also sensitive to various stressors. Our results also revealed that the levels of pseudohypha formation and biofilm formation were reduced in the null mutants compared to the wild type. This phenotypic defect could be partially rescued by supplementation with excess iron in the growth medium. The expression levels of the orthologues of various iron metabolism-related genes were also altered in the mutants compared to the parental strain. In conclusion, our report describes the role of CPAR2_603600 in iron homoeostasis maintenance as well as morphology and biofilm formation regulation in this pathogenic fungus.IMPORTANCEC. parapsilosis is the second or third most common opportunistic human-pathogenic Candida species, being responsible for severe fungal infections among immunocompromised patients, especially low-birth-weight infants (0 to 2 years of age). Among the major virulence factors that pathogenic fungi possess is the ability to compete with the host for essential micronutrients, including iron. Accessible iron is required for the maintenance of several metabolic processes. In order to obtain accessible iron from the host, pathogenic fungi have developed several iron acquisition and metabolic mechanisms. Although C. parapsilosis is a frequent cause of invasive candidiasis, little is known about what iron metabolic processes this fungus possesses that could contribute to the species' virulent behavior. In this study, we identified the multicopper oxidase FET3 gene that regulates iron homeostasis maintenance and also plays important roles in the morphology of the fungus as well as in biofilm formation, two additional factors in fungal virulence.
Highlights
Among all the essential micronutrients, iron plays an important role in mammalian biology
FET3 is not linked to virulence in C. albicans, we recently demonstrated that C. parapsilosis FET3 (CpFET3), besides playing a role in prostaglandin production, influences its virulence [19]; its role in iron metabolism remains unclear
Iron Metabolism Regulation, a Novel Function of CpFET3 query sequence, which is in contrast with the identification of the five FET3 orthologs FET3, FET31, FET33, FET34, and FET99 in analyses of C. albicans [8]
Summary
Among all the essential micronutrients, iron plays an important role in mammalian biology It is essential for pathogens infecting mammalian hosts, including bacteria, fungi, and protozoans. We identified the multicopper oxidase FET3 gene that regulates iron homeostasis maintenance and plays important roles in the morphology of the fungus as well as in biofilm formation, two additional factors in fungal virulence. Iron is one of the most important micronutrients necessary for the growth and propagation of pathogens during an infection It plays a crucial role in the structure of many proteins and in their enzymatic functions. The crucial role of iron uptake and metabolism in human-pathogenic fungi such as Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus is well known, and the role of iron during opportunistic fungal infections has been extensively studied [6, 7]. C. albicans has a transcription circuit for iron metabolism that enables survival within the human gastrointestinal tract as a commensal organism [13]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.