Genome assembly and comparative genome analysis of the basidiomycetous yeast Naganishia randhawae isolated from avian guano in South Africa

• Main Author: Tshisekedi, Kalonji Abondance
• Format: Thesis
• Language: English
• Published: 2021
• Subjects: Guano; Antarc*; Antarctica
• Online Access: https://hdl.handle.net/10539/33082

A dissertation submitted in fulfilment of the requirements for the degree Master of Science (in Molecular and Cell Biology) in the Faculty of Science, University of the Witwatersrand The genus Naganishiawas recently re-established with the aim of addressing the diversity and heterogeneity of the yeast genus Cryptococcus. Many members of this genus have been isolated from harsh terrestrial conditions, including the dry cold valleys of Antarctica and the Atacama Desert. As a result, they have developed adaptive strategies to deal with the stressors associated with cold environments, such as desiccation, reduced availability of water, low availability of nutrients, high levels of ultraviolet (UV) radiation, high or low pH, and high osmotic pressure. Clinical manifestations of Naganishia species often include cutaneous lesions, encephalitis, keratitis, onychomycosis, and pneumonia. Members of this genus also have significant biotechnological value due to their capability to produce single cell oils (SCOs) and cold-active enzymes, which can be used in a variety of biotechnological and industrial applications that require low operating temperatures .Despite their potential biotechnological, environmental, and medical importance, the mechanisms underlying the diverse functions of Naganishia species remains poorly understood. In this study, we present the first genome sequence of N. randhawaeeABCC1, which was isolated from avian guano in South Africa. The genome of this strain was further explored using comparative genomic and phylogenomic analysis. The relevant literature on the taxonomy, ecology, and pathogenicity of Naganishia spp. is reviewed in Chapter 1. A comprehensive taxonomic history of the genus Naganishia is followed by an overview of the different ecological niches, with an emphasis on extreme ecosystems. Finally, biotechnological importance, clinical manifestations and factors that contribute to Naganishia pathogenicity are addressed. In Chapter 2, sequencing of N. randhawaeeABCC1 was performed using the ...