title: Trichosporon jirovecii-mediated synthesis of cadmium sulfide nanoparticles.
abstract: Cadmium sulphide is one of the most promising materials for solar cells and of great interest due to its useful applications in photonics and electronics, thus the development of bio-mediated synthesis of cadmium sulphide nanoparticles (CdS NPs) is one of the essential areas in nanoparticles. The present study demonstrates for the first time the eco-friendly biosynthesis of CdS NPs using the yeast Trichosporon jirovecii. The biosynthesis of CdS NPs were confirmed by UV-Vis spectrum and characterized by X-ray diffraction assay and electron microscopy. Scanning and transmission electron microscope analyses shows the formation of spherical CdS NPs with a size range of about 6-15 nm with a mean Cd:S molar ratio of 1.0:0.98. T. jirovecii produced hydrogen sulfide on cysteine containing medium confirmed by positive cysteine-desulfhydrase activity and the colony color turned yellow on 0.1 mM cadmium containing medium. T. jirovecii tolerance to cadmium was increased by the UV treatment and three 0.6 mM cadmium tolerant mutants were generated upon the UV radiation treatment. The overall results indicated that T. jirovecii could tolerate cadmium toxicity by its conversion into CdS NPs on cysteine containing medium using cysteine-desulfhydrase as a defense response mechanism.
authors.affiliation: Department of Industrial Biotechnology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City, Egypt.
authors.forename: Ashraf Farag
authors.initials: AF
authors.lastname: El-Baz
authors.affiliation: Department of Industrial Biotechnology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City, Egypt.
authors.forename: Noha Mohamed
authors.initials: NM
authors.lastname: Sorour
authors.affiliation: Department of Microbiology, Faculty of Science, Ain Shams University, Cairo, Egypt.
authors.forename: Youssria Mohamed
authors.initials: YM
authors.lastname: Shetaia
mesh_terms: D002104:Cadmium / Q000737:chemistry / Q000633:toxicity*; D019187:Cadmium Compounds / Q000737:chemistry / Q000378:metabolism*; D003542:Cystathionine gamma-Lyase / Q000378:metabolism; D008854:Microscopy, Electron; D053758:Nanoparticles / Q000378:metabolism*; D013440:Sulfides / Q000737:chemistry / Q000378:metabolism*; D014250:Trichosporon / Q000187:drug effects* / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D019187:Cadmium Compounds; D013440:Sulfides; D002104:Cadmium; C034939:cadmium sulfide; D003542:Cystathionine gamma-Lyase
keywords: Cadmium sulphide; Cysteine-desulfhydrase; Nanoparticles; Solar cells; Trichosporon jirovecii