title: Thermotolerance and molecular chaperone function of an SGT1-like protein from the psychrophilic yeast, Glaciozyma antarctica.
abstract: The ability of eukaryotes to adapt to an extreme range of temperatures is critically important for survival. Although adaptation to extreme high temperatures is well understood, reflecting the action of molecular chaperones, it is unclear whether these molecules play a role in survival at extremely low temperatures. The recent genome sequencing of the yeast Glaciozyma antarctica, isolated from Antarctic sea ice near Casey Station, provides an opportunity to investigate the role of molecular chaperones in adaptation to cold temperatures. We isolated a G. antarctica homologue of small heat shock protein 20 (HSP20), GaSGT1, and observed that the GaSGT1 mRNA expression in G. antarctica was markedly increased following culture exposure at low temperatures. Additionally, we demonstrated that GaSGT1 overexpression in Escherichia coli protected these bacteria from exposure to both high and low temperatures, which are lethal for growth. The recombinant GaSGT1 retained up to 60 % of its native luciferase activity after exposure to luciferase-denaturing temperatures. These results suggest that GaSGT1 promotes cell thermotolerance and employs molecular chaperone-like activity toward temperature assaults.
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600, Selangor, Malaysia.
authors.forename: Nur Athirah
authors.initials: NA
authors.lastname: Yusof
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600, Selangor, Malaysia.
authors.forename: Noor Haza Fazlin
authors.initials: NH
authors.lastname: Hashim
authors.affiliation: Department of Animal, Plant and Soil Science and Centre for AgriBioscience (AgriBio), La Trobe University, Melbourne, 3086, VIC, Australia.
authors.forename: Travis
authors.initials: T
authors.lastname: Beddoe
authors.affiliation: Malaysia Genome Institute, Jalan Bangi, Bangi, 43600, Selangor, Malaysia.
authors.forename: Nor Muhammad
authors.initials: NM
authors.lastname: Mahadi
authors.affiliation: Department of Biosciences Engineering, Faculty of Chemical and Natural Resources Engineering, Universiti Teknologi Malaysia, Skudai, 81310, Johor, Malaysia.
authors.forename: Rosli Md
authors.initials: RM
authors.lastname: Illias
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600, Selangor, Malaysia.
authors.forename: Farah Diba Abu
authors.initials: FD
authors.lastname: Bakar
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 43600, Selangor, Malaysia. munir@ukm.edu.my.
authors.forename: Abdul Munir Abdul
authors.initials: AM
authors.lastname: Murad
mesh_terms: D000595:Amino Acid Sequence; D001487:Basidiomycota / Q000235:genetics / Q000378:metabolism*; D057075:Enzyme Assays; D004926:Escherichia coli / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D008156:Luciferases / Q000378:metabolism; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020539:Sequence Analysis, Protein; D013696:Temperature; D000071436:Thermotolerance
chemical_list: D005656:Fungal Proteins; D018832:Molecular Chaperones; D012333:RNA, Messenger; D008156:Luciferases
keywords: Cloning; Expression; HSP90; Luciferase; Molecular chaperone; SGT1