Copper stress response in yeast Rhodotorula mucilaginosa AN5 isolated from sea ice, Antarctic. Issue 3 (21st June 2018)

• Record Type: Journal Article
• Authors: Kan, Guangfeng; Wang, Xiaofei; Jiang, Jie; Zhang, Chengsheng; Chi, Minglei; Ju, Yun; Shi, Cuijuan
• Is Part Of: MicrobiologyOpen. Volume 8:Issue 3(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-06-21
• Subjects: adaptive responses -- Antarctica yeast -- copper stress -- proteomics; Microbiology -- Periodicals; 579
• DOI: 10.1002/mbo3.657
• Languages: English
• ISSNs: 2045-8827

Abstract

Abstract: Heavy metal pollution in Antarctic is serious by anthropogenic emissions and atmospheric transport. To dissect the heavy metal adaptation mechanisms of sea‐ice organisms, a basidiomycetous yeast strain AN5 was isolated and its cellular changes were analyzed. Morphological, physiological, and biochemical characterization indicated that this yeast strain belonged to Rhodotorula mucilaginosa AN5. Heavy metal resistance pattern of Cd > Pb = Mn > Cu > Cr > Hg was observed. Scanning electron microscopic (SEM) results exhibited altered cell surface morphology under the influence of copper metal compared to that with control. The determination of physiological and biochemical changes manifested that progressive copper treatment significantly increased antioxidative reagents content and enzymes activity in the red yeast, which quench the active oxygen species to maintain the intercellular balance of redox state and ensure the cellular fission and growth. Comparative proteomic analysis revealed that, under 2 mM copper stress, 95 protein spots were tested reproducible changes of at least 10‐fold in cells. Among 95 protein spots, 43 were elevated and 52 were decreased synthesis. After MALDI TOF MS/MS analysis, 51 differentially expressed proteins were identified successfully and classified into six functional groups, including carbohydrate and energy metabolism, nucleotide and protein metabolism, protein folding, antioxidant system, signaling, and unknown function proteins. Function analysis indicated that carbohydrate and energy metabolism‐, nucleotide and protein metabolism‐, and protein folding‐related proteins played central role to the heavy metal resistance of Antarctic yeast. Generally, the results revealed that the yeast has a great capability to cope with heavy metal stress and activate the physiological and protein mechanisms, which allow more efficient recovery after copper stress. Our studies increase understanding of the molecular resistance mechanism of polar yeast to heavy metal, which will be benefitted for the sea‐ice isolates to be a potential candidate for bioremediation of metal‐contaminated environments. Abstract : Antarctic yeast had unusually high levels of resistance to metal ions; Morphological and physiological changes of yeast stressed by copper were reported firstly; The proteomics identification indicated, for the first time, carbohydrate and energy metabolism‐, nucleotide and protein metabolism‐, protein folding‐related proteins played central role to the heavy metal resistance of Antarctic yeast.