title: Ethanol induced astaxanthin accumulation and transcriptional expression of carotenogenic genes in Haematococcus pluvialis.
abstract: Haematococcus pluvialis is one of the most promising natural sources of astaxanthin. However, inducing the accumulation process has become one of the primary obstacles in astaxanthin production. In this study, the effect of ethanol on astaxanthin accumulation was investigated. The results demonstrated that astaxanthin accumulation occurred with ethanol addition even under low-light conditions. The astaxanthin productivity could reach 11.26 mg L(-1) d(-1) at 3% (v/v) ethanol, which was 2.03 times of that of the control. The transcriptional expression patterns of eight carotenogenic genes were evaluated using real-time PCR. The results showed that ethanol greatly enhanced transcription of the isopentenyl diphosphate (IPP) isomerase genes (ipi-1 and ipi-2), which were responsible for isomerization reaction of IPP and dimethylallyl diphosphate (DMAPP). This finding suggests that ethanol induced astaxanthin biosynthesis was up-regulated mainly by ipi-1 and ipi-2 at transcriptional level, promoting isoprenoid synthesis and substrate supply to carotenoid formation. Thus ethanol has the potential to be used as an effective reagent to induce astaxanthin accumulation in H. pluvialis.
authors.affiliation: Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, PR China.
authors.forename: Zewen
authors.initials: Z
authors.lastname: Wen
authors.affiliation: Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, PR China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, PR China.
authors.forename: Yuyong
authors.initials: Y
authors.lastname: Hou
authors.affiliation: Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, PR China.
authors.forename: Chenfeng
authors.initials: C
authors.lastname: Liu
authors.affiliation: Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, PR China.
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
authors.affiliation: Shandong Jinjing Biotechnology Co., Ltd, Shandong 261313, PR China.
authors.forename: Yubin
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, PR China. Electronic address: chen_fj@tib.cas.cn.
authors.forename: Fangjian
authors.initials: F
authors.lastname: Chen
mesh_terms: D020418:Algal Proteins / Q000235:genetics / Q000378:metabolism; D000975:Antioxidants / Q000378:metabolism; D019748:Carbon-Carbon Double Bond Isomerases / Q000235:genetics / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects / Q000528:radiation effects; D045782:Hemiterpenes / Q000378:metabolism; D008027:Light; D008855:Microscopy, Electron, Scanning; D009943:Organophosphorus Compounds / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D013379:Substrate Specificity; D016823:Volvocida / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D024341:Xanthophylls / Q000096:biosynthesis / Q000378:metabolism
chemical_list: D020418:Algal Proteins; D000975:Antioxidants; D045782:Hemiterpenes; D009943:Organophosphorus Compounds; D024341:Xanthophylls; C004809:isopentenyl pyrophosphate; C043060:3,3-dimethylallyl pyrophosphate; D000431:Ethanol; C005948:astaxanthine; D019748:Carbon-Carbon Double Bond Isomerases; C021453:isopentenyldiphosphate delta-isomerase
keywords: Astaxanthin; Ethanol; Fed-batch induction; Haematococcus pluvialis; ipi