Role of CgHOG1 in Stress Responses and Glycerol Overproduction of Candida glycerinogenes
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Candida glycerinogenes, the glycerol producer with excellent multi-stress tolerances, is considered to be a potential biotechnological host used in the production of glycerol and its derivatives under extreme fermentation conditions. In this study, to evaluate the multiple roles of mitogen-activated protein kinase CgHOG1, we constructed a gene disruption system in the diploid C. glycerinogenes to obtain CgHOG1 null mutant. Pseudohyphae generation of the CgHOG1 mutant under non-inducing condition indicated a repressor role in morphological transitions. Disruption of CgHOG1 resulted in increased sensitivities to osmotic, acetic acid, and oxidative stress but not involved in thermotolerance. In the CgHOG1 mutant, NaCl shock failed to stimulate the accumulation of intracellular glycerol and was fatal. In addition, the CgHOG1 mutant displayed a significant prolonged growth lag phase in YPD medium with no decrease in glycerol production, whereas the mutant cannot grow under hyperosmotic condition with no detectable glycerol in broth. These results suggested that CgHOG1 plays important roles in morphogenesis and multi-stress tolerance. The growth and glycerol overproduction under osmotic stress are heavily dependent on CgHOG1 kinase.
KeywordsHyperosmotic Stress Glycerol Production Kluyveromyces Marxianus Hyperosmotic Shock Synthetic Dextrose
This work was funded by China National “863” High-Tech Program (No. 2012AA021201) and supported by the National Natural Science Foundation of China (Nos. 31570052, 31601456), the Natural Science Foundation of Jiangsu Province (Nos. BK20140134, BK20140138), the Six Talent Peaks Project in Jiangsu Province (No. 2014-XCL-017), and the Fundamental Research Funds for the Central Universities (JUSRP11431). We thank Dr. Jiangye Chen (Chinese Academy of Sciences) for plasmid pCUB6.
- 7.Eisman B, Alonso-Monge R, Roman E, Arana D, Nombela C, Pla J (2006) The Cek1 and Hog1 mitogen-activated protein kinases play complementary roles in cell wall biogenesis and chlamydospore formation in the fungal pathogen Candida albicans. Eukaryot Cell 5(2):347–358CrossRefPubMedPubMedCentralGoogle Scholar