An indigenous inland genotype of the black yeast Hortaea werneckii inhabiting the great pyramid of Giza, Egypt

Abstract

Within the context of cultural heritage conservation, the biological study of tangible archeological sites is an important task to extend their existence and strengthen the transmission of their cultural value to future generations. In Egypt, a hyper-arid region, a microcolonial fungus with inky black growth was observed on a stone surface in the royal corridor of the Great Pyramid of Giza (King Khufu’s pyramid). The isolate was studied and characterized by microscopic morphometric measurements, evaluation of enzymatic activities, and genotyping techniques. The isolate was identified as Hortaea werneckii, a pleomorphic black yeast that naturally inhabits hypersaline environments and infects human skin. It has been reported from humid temperate, subtropical, and tropical zones, mainly from marine habitats and adjacent areas, and is associated with marine life. Since it was observed in an unusual habitat, it raises the question of its type and origin, whether environmental or clinical. The Egyptian Hortaea werneckii GPS5 isolate was profiled and characterized by adaptive extremophilic tolerance to arid salt stress, low portability to infect human skin, and the capability of solubilizing calcite; besides it was phylogenetically clustered with previous recorded environmental accessions. A profile that matches the biodeterioration fungal agents known as rock-inhabiting fungi, a potential threat to cultural heritage sites that requires attention and prevention plans.

Culturable and unculturable potential heterotrophic microbiological threats to the oldest pyramids of the Memphis necropolis, Egypt

“…Previously, in Egyptian monuments, an environmental extremotolerant genotype of the black yeast Hortaea werneckii GPS5 was isolated from a stone surface in the Great Pyramid of Giza’s royal corridor (King Khufu’s pyramid; Rizk and Magdy, 2022 ). Three xerophilic fungi, namely Aspergillus amstelodami , Aspergillus chevalieri , and Aspergillus repens , and six non-xerophilic species Alternaria alternata , Aspergillus terreus , Cladosporium herbarum , and Penicillium chrysogenum were isolated from Al-Shatby and El-Anfoushi archeological tombs in the Alexandria governorate (Alexandria city), respectively ( Afifi and Geweely, 2011 ).…”