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Saha D, Gregor JB, Hoda S, Eastman KE, Navarrete M, Wisecaver JH, Briggs SD. Candida glabrata maintains two Hap1 homologs, Zcf27 and Zcf4, for distinct roles in ergosterol gene regulation to mediate sterol homeostasis under azole and hypoxic conditions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.20.599910. [PMID: 38979343 PMCID: PMC11230168 DOI: 10.1101/2024.06.20.599910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Candida glabrata exhibits innate resistance to azole antifungal drugs but also has the propensity to rapidly develop clinical drug resistance. Azole drugs, which target Erg11, is one of the three major classes of antifungals used to treat Candida infections. Despite their widespread use, the mechanism controlling azole-induced ERG gene expression and drug resistance in C. glabrata has primarily revolved around Upc2 and/or Pdr1. In this study, we determined the function of two zinc cluster transcription factors, Zcf27 and Zcf4, as direct but distinct regulators of ERG genes. Our phylogenetic analysis revealed C. glabrata Zcf27 and Zcf4 as the closest homologs to Saccharomyces cerevisiae Hap1. Hap1 is a known zinc cluster transcription factor in S. cerevisiae in controlling ERG gene expression under aerobic and hypoxic conditions. Interestingly, when we deleted HAP1 or ZCF27 in either S. cerevisiae or C. glabrata, respectively, both deletion strains showed altered susceptibility to azole drugs, whereas the strain deleted for ZCF4 did not exhibit azole susceptibility. We also determined that the increased azole susceptibility in a zcf27Δ strain is attributed to decreased azole-induced expression of ERG genes, resulting in decreased levels of total ergosterol. Surprisingly, Zcf4 protein expression is barely detected under aerobic conditions but is specifically induced under hypoxic conditions. However, under hypoxic conditions, Zcf4 but not Zcf27 was directly required for the repression of ERG genes. This study provides the first demonstration that Zcf27 and Zcf4 have evolved to serve distinct roles allowing C. glabrata to adapt to specific host and environmental conditions.
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Affiliation(s)
| | | | | | | | | | | | - Scott D. Briggs
- Department of Biochemistry
- Purdue University Institute for Cancer Research
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2
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Wang J, Cao Y, Shi D, Zhang Z, Li X, Chen C. Crucial Involvement of Heme Biosynthesis in Vegetative Growth, Development, Stress Response, and Fungicide Sensitivity of Fusarium graminearum. Int J Mol Sci 2024; 25:5268. [PMID: 38791308 PMCID: PMC11120706 DOI: 10.3390/ijms25105268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 05/07/2024] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
Heme biosynthesis is a highly conserved pathway from bacteria to higher animals. Heme, which serves as a prosthetic group for various enzymes involved in multiple biochemical processes, is essential in almost all species, making heme homeostasis vital for life. However, studies on the biological functions of heme in filamentous fungi are scarce. In this study, we investigated the role of heme in Fusarium graminearum. A mutant lacking the rate-limiting enzymes in heme synthesis, coproporphyrinogen III oxidase (Cpo) or ferrochelatase (Fc), was constructed using a homologous recombination strategy. The results showed that the absence of these enzymes was lethal to F. graminearum, but the growth defect could be rescued by the addition of hemin, so we carried out further studies with the help of hemin. The results demonstrated that heme was required for the activity of FgCyp51, and its absence increased the sensitivity to tebuconazole and led to the upregulation of FgCYP51 in F. graminearum. Additionally, heme plays an indispensable role in the life cycle of F. graminearum, which is essential for vegetative growth, conidiation, external stress response (especially oxidative stress), lipid accumulation, fatty acid β-oxidation, autophagy, and virulence.
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Affiliation(s)
| | | | | | | | | | - Changjun Chen
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; (J.W.); (Y.C.); (D.S.); (Z.Z.); (X.L.)
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3
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Wang S, Meng D, Feng M, Li C, Wang Y. Efficient Plant Triterpenoids Synthesis in Saccharomyces cerevisiae: from Mechanisms to Engineering Strategies. ACS Synth Biol 2024; 13:1059-1076. [PMID: 38546129 DOI: 10.1021/acssynbio.4c00061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
Triterpenoids possess a range of biological activities and are extensively utilized in the pharmaceutical, food, cosmetic, and chemical industries. Traditionally, they are acquired through chemical synthesis and plant extraction. However, these methods have drawbacks, including high energy consumption, environmental pollution, and being time-consuming. Recently, the de novo synthesis of triterpenoids in microbial cell factories has been achieved. This represents a promising and environmentally friendly alternative to traditional supply methods. Saccharomyces cerevisiae, known for its robustness, safety, and ample precursor supply, stands out as an ideal candidate for triterpenoid biosynthesis. However, challenges persist in industrial production and economic feasibility of triterpenoid biosynthesis. Consequently, metabolic engineering approaches have been applied to improve the triterpenoid yield, leading to substantial progress. This review explores triterpenoids biosynthesis mechanisms in S. cerevisiae and strategies for efficient production. Finally, the review also discusses current challenges and proposes potential solutions, offering insights for future engineering.
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Affiliation(s)
- Shuai Wang
- Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Dong Meng
- Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Meilin Feng
- Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Chun Li
- Key Laboratory for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Ying Wang
- Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
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4
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Gnaien M, Maufrais C, Rebai Y, Kallel A, Ma L, Hamouda S, Khalsi F, Meftah K, Smaoui H, Khemiri M, Hadj Fredj S, Bachellier-Bassi S, Najjar I, Messaoud T, Boussetta K, Kallel K, Mardassi H, d’Enfert C, Bougnoux ME, Znaidi S. A gain-of-function mutation in zinc cluster transcription factor Rob1 drives Candida albicans adaptive growth in the cystic fibrosis lung environment. PLoS Pathog 2024; 20:e1012154. [PMID: 38603707 PMCID: PMC11037546 DOI: 10.1371/journal.ppat.1012154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 04/23/2024] [Accepted: 03/26/2024] [Indexed: 04/13/2024] Open
Abstract
Candida albicans chronically colonizes the respiratory tract of patients with Cystic Fibrosis (CF). It competes with CF-associated pathogens (e.g. Pseudomonas aeruginosa) and contributes to disease severity. We hypothesize that C. albicans undergoes specific adaptation mechanisms that explain its persistence in the CF lung environment. To identify the underlying genetic and phenotypic determinants, we serially recovered 146 C. albicans clinical isolates over a period of 30 months from the sputum of 25 antifungal-naive CF patients. Multilocus sequence typing analyses revealed that most patients were individually colonized with genetically close strains, facilitating comparative analyses between serial isolates. We strikingly observed differential ability to filament and form monospecies and dual-species biofilms with P. aeruginosa among 18 serial isolates sharing the same diploid sequence type, recovered within one year from a pediatric patient. Whole genome sequencing revealed that their genomes were highly heterozygous and similar to each other, displaying a highly clonal subpopulation structure. Data mining identified 34 non-synonymous heterozygous SNPs in 19 open reading frames differentiating the hyperfilamentous and strong biofilm-former strains from the remaining isolates. Among these, we detected a glycine-to-glutamate substitution at position 299 (G299E) in the deduced amino acid sequence of the zinc cluster transcription factor ROB1 (ROB1G299E), encoding a major regulator of filamentous growth and biofilm formation. Introduction of the G299E heterozygous mutation in a co-isolated weak biofilm-former CF strain was sufficient to confer hyperfilamentous growth, increased expression of hyphal-specific genes, increased monospecies biofilm formation and increased survival in dual-species biofilms formed with P. aeruginosa, indicating that ROB1G299E is a gain-of-function mutation. Disruption of ROB1 in a hyperfilamentous isolate carrying the ROB1G299E allele abolished hyperfilamentation and biofilm formation. Our study links a single heterozygous mutation to the ability of C. albicans to better survive during the interaction with other CF-associated microbes and illuminates how adaptive traits emerge in microbial pathogens to persistently colonize and/or infect the CF-patient airways.
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Affiliation(s)
- Mayssa Gnaien
- Institut Pasteur de Tunis, University of Tunis El Manar, Laboratoire de Microbiologie Moléculaire, Vaccinologie et Développement Biotechnologique (LR16IPT01), Tunis, Tunisia
| | - Corinne Maufrais
- Institut Pasteur, Université Paris Cité, INRAE USC2019A, Département Mycologie, Unité Biologie et Pathogénicité Fongiques, Paris, France
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, F-75015 Paris, France
| | - Yasmine Rebai
- Institut Pasteur de Tunis, University of Tunis El Manar, Laboratoire de Microbiologie Moléculaire, Vaccinologie et Développement Biotechnologique (LR16IPT01), Tunis, Tunisia
| | - Aicha Kallel
- Institut Pasteur de Tunis, University of Tunis El Manar, Laboratoire de Microbiologie Moléculaire, Vaccinologie et Développement Biotechnologique (LR16IPT01), Tunis, Tunisia
- Hôpital La Rabta, Laboratoire de Parasitologie et de Mycologie, UR17SP03, Tunis, Tunisia
| | - Laurence Ma
- Institut Pasteur, Université Paris Cité, Biomics core facility, Centre de Ressources et Recherche Technologique (C2RT), Paris, France
| | - Samia Hamouda
- Hôpital d’Enfants Béchir Hamza de Tunis, Tunis, Tunisia
| | - Fatma Khalsi
- Hôpital d’Enfants Béchir Hamza de Tunis, Tunis, Tunisia
| | | | - Hanen Smaoui
- Hôpital d’Enfants Béchir Hamza de Tunis, Tunis, Tunisia
| | - Monia Khemiri
- Hôpital d’Enfants Béchir Hamza de Tunis, Tunis, Tunisia
| | | | - Sophie Bachellier-Bassi
- Institut Pasteur, Université Paris Cité, INRAE USC2019A, Département Mycologie, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Imène Najjar
- Institut Pasteur, Université Paris Cité, Biomics core facility, Centre de Ressources et Recherche Technologique (C2RT), Paris, France
| | | | | | - Kalthoum Kallel
- Hôpital La Rabta, Laboratoire de Parasitologie et de Mycologie, UR17SP03, Tunis, Tunisia
| | - Helmi Mardassi
- Institut Pasteur de Tunis, University of Tunis El Manar, Laboratoire de Microbiologie Moléculaire, Vaccinologie et Développement Biotechnologique (LR16IPT01), Tunis, Tunisia
| | - Christophe d’Enfert
- Institut Pasteur, Université Paris Cité, INRAE USC2019A, Département Mycologie, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Marie-Elisabeth Bougnoux
- Institut Pasteur, Université Paris Cité, INRAE USC2019A, Département Mycologie, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Sadri Znaidi
- Institut Pasteur de Tunis, University of Tunis El Manar, Laboratoire de Microbiologie Moléculaire, Vaccinologie et Développement Biotechnologique (LR16IPT01), Tunis, Tunisia
- Institut Pasteur, Université Paris Cité, INRAE USC2019A, Département Mycologie, Unité Biologie et Pathogénicité Fongiques, Paris, France
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5
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Wang J, Shen J, Chen D, Liao B, Chen X, Zong Y, Wei Y, Shi Y, Liu Y, Gou L, Zhou X, Cheng L, Ren B. Secretory IgA reduced the ergosterol contents of Candida albicans to repress its hyphal growth and virulence. Appl Microbiol Biotechnol 2024; 108:244. [PMID: 38421461 PMCID: PMC10904422 DOI: 10.1007/s00253-024-13063-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 01/31/2024] [Accepted: 02/08/2024] [Indexed: 03/02/2024]
Abstract
Candida albicans, one of the most prevalent conditional pathogenic fungi, can cause local superficial infections and lethal systemic infections, especially in the immunocompromised population. Secretory immunoglobulin A (sIgA) is an important immune protein regulating the pathogenicity of C. albicans. However, the actions and mechanisms that sIgA exerts directly against C. albicans are still unclear. Here, we investigated that sIgA directs against C. albicans hyphal growth and virulence to oral epithelial cells. Our results indicated that sIgA significantly inhibited C. albicans hyphal growth, adhesion, and damage to oral epithelial cells compared with IgG. According to the transcriptome and RT-PCR analysis, sIgA significantly affected the ergosterol biosynthesis pathway. Furthermore, sIgA significantly reduced the ergosterol levels, while the addition of exogenous ergosterol restored C. albicans hyphal growth and adhesion to oral epithelial cells, indicating that sIgA suppressed the growth of hyphae and the pathogenicity of C. albicans by reducing its ergosterol levels. By employing the key genes mutants (erg11Δ/Δ, erg3Δ/Δ, and erg3Δ/Δ erg11Δ/Δ) from the ergosterol pathway, sIgA lost the hyphal inhibition on these mutants, while sIgA also reduced the inhibitory effects of erg11Δ/Δ and erg3Δ/Δ and lost the inhibition of erg3Δ/Δ erg11Δ/Δ on the adhesion to oral epithelial cells, further proving the hyphal repression of sIgA through the ergosterol pathway. We demonstrated for the first time that sIgA inhibited C. albicans hyphal development and virulence by affecting ergosterol biosynthesis and suggest that ergosterol is a crucial regulator of C. albicans-host cell interactions. KEY POINTS: • sIgA repressed C. albicans hyphal growth • sIgA inhibited C. albicans virulence to host cells • sIgA affected C. albicans hyphae and virulence by reducing its ergosterol levels.
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Affiliation(s)
- Jiannan Wang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jiawei Shen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Ding Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Binyou Liao
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Xi Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yawen Zong
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yu Wei
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yangyang Shi
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yaqi Liu
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Lichen Gou
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Lei Cheng
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China.
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China.
| | - Biao Ren
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610041, Sichuan, China.
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6
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Wang S, Zhan C, Nie S, Tian D, Lu J, Wen M, Qiao J, Zhu H, Caiyin Q. Enzyme and Metabolic Engineering Strategies for Biosynthesis of α-Farnesene in Saccharomyces cerevisiae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:12452-12461. [PMID: 37574876 DOI: 10.1021/acs.jafc.3c03677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
α-Farnesene, a type of acyclic sesquiterpene, is an important raw material in agriculture, aircraft fuel, and the chemical industry. In this study, we constructed an efficient α-farnesene-producing yeast cell factory by combining enzyme and metabolic engineering strategies. First, we screened different plants for α-farnesene synthase (AFS) with the best activity and found that AFS from Camellia sinensis (CsAFS) exhibited the most efficient α-farnesene production in Saccharomyces cerevisiae 4741. Second, the metabolic flux of the mevalonate pathway was increased to improve the supply of the precursor farnesyl pyrophosphate. Third, inducing site-directed mutagenesis in CsAFS, the CsAFSW281C variant was obtained, which considerably increased α-farnesene production. Fourth, the N-terminal serine-lysine-isoleucine-lysine (SKIK) tag was introduced to construct the SKIK∼CsAFSW281C variant, which further increased α-farnesene production to 2.8 g/L in shake-flask cultures. Finally, the α-farnesene titer of 28.3 g/L in S. cerevisiae was obtained by fed-batch fermentation in a 5 L bioreactor.
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Affiliation(s)
- Shengli Wang
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
- Zhejiang Shaoxing Research Institute of Tianjin University, Shaoxing 312300, China
| | - Chuanling Zhan
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
- Zhejiang Shaoxing Research Institute of Tianjin University, Shaoxing 312300, China
| | - Shengxin Nie
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
- Zhejiang Shaoxing Research Institute of Tianjin University, Shaoxing 312300, China
| | - Daoguang Tian
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
- Zhejiang Shaoxing Research Institute of Tianjin University, Shaoxing 312300, China
| | - Juane Lu
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
- Zhejiang Shaoxing Research Institute of Tianjin University, Shaoxing 312300, China
| | - Mingzhang Wen
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
| | - Jianjun Qiao
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
- Zhejiang Shaoxing Research Institute of Tianjin University, Shaoxing 312300, China
| | - Hongji Zhu
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
| | - Qinggele Caiyin
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, People's Republic of China
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7
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Johnston EJ, Tallis J, Cunningham-Oakes E, Moses T, Moore SJ, Hosking S, Rosser SJ. Yeast lacking the sterol C-5 desaturase Erg3 are tolerant to the anti-inflammatory triterpenoid saponin escin. Sci Rep 2023; 13:13617. [PMID: 37604855 PMCID: PMC10442444 DOI: 10.1038/s41598-023-40308-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 08/08/2023] [Indexed: 08/23/2023] Open
Abstract
Escin is a mixture of over 30 glycosylated triterpenoid (saponin) structures, extracted from the dried fruit of horse chestnuts. Escin is currently used as an anti-inflammatory, and has potential applications in the treatment of arthritis and cancer. Engineered yeast would enable production of specific bioactive components of escin at industrial scale, however many saponins have been shown to be toxic to yeast. Here we report that a Saccharomyces cerevisiae strain specifically lacking the sterol C-5 desaturase gene ERG3, exhibits striking enhanced tolerance to escin treatment. Transcriptome analyses, as well as pre-mixing of escin with sterols, support the hypothesis that escin interacts directly with ergosterol, but not as strongly with the altered sterols present in erg3Δ. A diverse range of saponins are of commercial interest, and this research highlights the value of screening lipidome mutants to identify appropriate hosts for engineering the industrial production of saponins.
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Affiliation(s)
- Emily J Johnston
- Centre for Engineering Biology, University of Edinburgh, Edinburgh, EH9 3BD, UK.
| | - Jess Tallis
- Centre for Engineering Biology, University of Edinburgh, Edinburgh, EH9 3BD, UK
| | - Edward Cunningham-Oakes
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Tessa Moses
- EdinOmics, RRID:SCR_021838, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Simon J Moore
- Genetic Science Division, Thermo Fisher Scientific, 7 Kingsland Grange, Warrington, Cheshire, WA1 4SR, UK
| | - Sarah Hosking
- Unilever R&D Port Sunlight, Quarry Road East, Bebington, Wirral, CH63 3JW, UK
| | - Susan J Rosser
- Centre for Engineering Biology, University of Edinburgh, Edinburgh, EH9 3BD, UK.
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8
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Zhao C, Wang XH, Lu XY, Zong H, Zhuge B. Metabolic Engineering of Candida glycerinogenes for Sustainable Production of Geraniol. ACS Synth Biol 2023; 12:1836-1844. [PMID: 37271978 DOI: 10.1021/acssynbio.3c00195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Geraniol is a class of natural products that are widely used in the aroma industry due to their unique aroma. Here, to achieve the synthesis of geraniol and alleviate the intense competition from the yeast ergosterol pathway, a transcription factor-mediated ergosterol feedback system was developed in this study to autonomously regulate ergosterol metabolism and redirect carbon flux to geraniol synthesis. In addition, the modification of ergosterol-responsive promoters, the optimization of transcription factor expression intensity, and stepwise metabolic engineering resulted in a geraniol titer of 531.7 mg L-1. For sustainable production of geraniol, we constructed a xylose assimilation pathway in Candida glycerinogenes (C. glycerinogenes). Then, the xylose metabolic capacity was ameliorated and the growth of the engineered strain was rescued by activating the pentose phosphate (PP) pathway. Finally, we obtained 1091.6, 862.4, and 921.8 mg L-1 of geraniol in a 5 L bioreactor by using pure glucose, simulated wheat straw hydrolysates, and simulated sugarcane bagasse hydrolysates, with yields of 47.5, 57.9, and 59.1 mg g-1 DCW, respectively. Our study demonstrated that C. glycerinogenes has the potential to produce geraniol from lignocellulosic biomass, providing a powerful tool for the sustainable synthesis of other valuable monoterpenes.
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Affiliation(s)
- Cui Zhao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Xi-Hui Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Xin-Yao Lu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Hong Zong
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Bin Zhuge
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
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9
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Global metabolic rewiring of the nonconventional yeast Ogataea polymorpha for biosynthesis of the sesquiterpenoid β-elemene. Metab Eng 2023; 76:225-231. [PMID: 36828231 DOI: 10.1016/j.ymben.2023.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 02/10/2023] [Accepted: 02/19/2023] [Indexed: 02/24/2023]
Abstract
Bioproduction of natural products via microbial cell factories is a promising alternative to traditional plant extraction. Recently, nonconventional microorganisms have emerged as attractive chassis hosts for biomanufacturing. One such microorganism, Ogataea polymorpha is an industrial yeast used for protein expression with numerous advantages, such as thermal-tolerance, a wide substrate spectrum and high-density fermentation. Here, we systematically rewired the cellular metabolism of O. polymorpha to achieve high-level production of the sesquiterpenoid β-elemene by optimizing the mevalonate pathway, enhancing the supply of NADPH and acetyl-CoA, and downregulating competitive pathways. The engineered strain produced 509 mg/L and 4.7 g/L of β-elemene under batch and fed-batch fermentation, respectively. Therefore, this study identified the potential industrial application of O. polymorpha as a good microbial platform for producing sesquiterpenoids.
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10
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Jordá T, Barba-Aliaga M, Rozès N, Alepuz P, Martínez-Pastor MT, Puig S. Transcriptional regulation of ergosterol biosynthesis genes in response to iron deficiency. Environ Microbiol 2022; 24:5248-5260. [PMID: 36382795 DOI: 10.1111/1462-2920.16157] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/01/2022] [Indexed: 01/07/2023]
Abstract
Iron participates as an essential cofactor in the biosynthesis of critical cellular components, including DNA, proteins and lipids. The ergosterol biosynthetic pathway, which is an important target of antifungal treatments, depends on iron in four enzymatic steps. Our results in the model yeast Saccharomyces cerevisiae show that the expression of ergosterol biosynthesis (ERG) genes is tightly modulated by iron availability probably through the iron-dependent variation of sterol and heme levels. Whereas the transcription factors Upc2 and Ecm22 are responsible for the activation of ERG genes upon iron deficiency, the heme-dependent factor Hap1 triggers their Tup1-mediated transcriptional repression. The combined regulation by both activating and repressing regulatory factors allows for the fine-tuning of ERG transcript levels along the progress of iron deficiency, avoiding the accumulation of toxic sterol intermediates and enabling efficient adaptation to rapidly changing conditions. The lack of these regulatory factors leads to changes in the yeast sterol profile upon iron-deficient conditions. Both environmental iron availability and specific regulatory factors should be considered in ergosterol antifungal treatments.
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Affiliation(s)
- Tania Jordá
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
| | - Marina Barba-Aliaga
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, Burjassot, Valencia, Spain.,Departamento de Bioquímica y Biología Molecular, Universitat de València, Burjassot, Valencia, Spain
| | - Nicolas Rozès
- Departament de Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, Tarragona, Spain
| | - Paula Alepuz
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, Burjassot, Valencia, Spain.,Departamento de Bioquímica y Biología Molecular, Universitat de València, Burjassot, Valencia, Spain
| | | | - Sergi Puig
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Paterna, Valencia, Spain
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11
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Wei W, Gao S, Yi Q, Liu A, Yu S, Zhou J. Reengineering of 7-dehydrocholesterol biosynthesis in Saccharomyces cerevisiae using combined pathway and organelle strategies. Front Microbiol 2022; 13:978074. [PMID: 36016783 PMCID: PMC9398459 DOI: 10.3389/fmicb.2022.978074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 07/21/2022] [Indexed: 11/13/2022] Open
Abstract
7-Dehydrocholesterol (7-DHC) is a widely used sterol and a precursor of several costly steroidal drugs. In this study, 7-DHC biosynthesis pathway was constructed and modified in Saccharomyces cerevisiae. Firstly, the biosynthesis pathway was constructed by knocking out the competitive pathway genes ERG5 and ERG6 and integrating two DHCR24 copies from Gallus gallus at both sites. Then, 7-DHC titer was improved by knocking out MOT3, which encoded a transcriptional repressor for the 7-DHC biosynthesis pathway. Next, by knocking out NEM1 and PAH1, 7-DHC accumulation was improved, and genes upregulation was verified by quantitative PCR (qPCR). Additionally, tHMG1, IDI1, ERG2, ERG3, DHCR24, POS5, and CTT1 integration into multi-copy sites was used to convert precursors to 7-DHC, and increase metabolic flux. Finally, qPCR confirmed the significant up-regulation of key genes transcriptional levels. In a 96 h shaker flask fermentation, the 7-DHC titer was 649.5 mg/L by de novo synthesis. In a 5 L bioreactor, the 7-DHC titer was 2.0 g/L, which was the highest 7-DHC titer reported to date. Our study is of great significance for the industrial production of 7-DHC and steroid development for medical settings.
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Affiliation(s)
- Wenqian Wei
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, and School of Biotechnology, Jiangnan University, Wuxi, China
- Science Center for Future Foods, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Song Gao
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, and School of Biotechnology, Jiangnan University, Wuxi, China
- Science Center for Future Foods, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Qiong Yi
- Changsha Hospital for Maternal & Child Health Care, Changsha, China
| | - Anjian Liu
- Hunan Kerey Pharmaceutical Co., Ltd., Shaoyang, China
| | - Shiqin Yu
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, and School of Biotechnology, Jiangnan University, Wuxi, China
- Science Center for Future Foods, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jingwen Zhou
- Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology, and School of Biotechnology, Jiangnan University, Wuxi, China
- Science Center for Future Foods, School of Biotechnology, Jiangnan University, Wuxi, China
- Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, China
- *Correspondence: Jingwen Zhou,
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12
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Liu Y, Wang Z, Cui Z, Qi Q, Hou J. Progress and perspectives for microbial production of farnesene. BIORESOURCE TECHNOLOGY 2022; 347:126682. [PMID: 35007732 DOI: 10.1016/j.biortech.2022.126682] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/30/2021] [Accepted: 01/02/2022] [Indexed: 06/14/2023]
Abstract
Farnesene is increasingly used in industry, agriculture, and other fields due to its unique and excellent properties, necessitating its efficient synthesis. Microbial synthesis is an ideal farnesene production method. Recently, researchers have used several strategies to optimize the production performance of microorganisms. This review summarized these strategies, including regulation of farnesene synthesis pathways, and proposed some emerging tools and methods in stain engineering. Meanwhile, new farnesene biosynthetic pathways and effective farnesene production from cheap or waste substrates were emphatically introduced. Finally, future farnesene biosynthesis challenges were discussed.
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Affiliation(s)
- Yinghang Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Zhaoxuan Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Zhiyong Cui
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Qingsheng Qi
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China
| | - Jin Hou
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, PR China.
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13
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Azole-resistant alleles of
ERG11
in
Candida glabrata
trigger activation of the Pdr1 and Upc2A transcription factors. Antimicrob Agents Chemother 2022; 66:e0209821. [DOI: 10.1128/aac.02098-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Azoles, the most commonly used antifungal drugs, specifically inhibit the fungal lanosterol α-14 demethylase enzyme, which is referred to as Erg11. Inhibition of Erg11 ultimately leads to a reduction in ergosterol production, an essential fungal membrane sterol. Many
Candida
species, such as
Candida albicans
, develop mutations in this enzyme which reduces the azole binding affinity and results in increased resistance.
Candida glabrata
is also a pathogenic yeast that has low intrinsic susceptibility to azole drugs and easily develops elevated resistance. In
C. glabrata
, these azole resistant mutations typically cause hyperactivity of the Pdr1 transcription factor and rarely lie within the
ERG11
gene. Here, we generated
C. glabrata
ERG11
mutations that were analogous to azole resistance alleles from
C. albicans
ERG11
. Three different Erg11 forms (Y141H, S410F, and the corresponding double mutant (DM)) conferred azole resistance in
C. glabrata
with the DM Erg11 form causing the strongest phenotype. The DM Erg11 also induced cross-resistance to amphotericin B and caspofungin. Resistance caused by the DM allele of
ERG11
imposed a fitness cost that was not observed with hyperactive
PDR1
alleles. Crucially, the presence of the DM
ERG11
allele was sufficient to activate the Pdr1 transcription factor in the absence of azole drugs. Our data indicate that azole resistance linked to changes in
ERG11
activity can involve cellular effects beyond an alteration in this key azole target enzyme. Understanding the physiology linking ergosterol biosynthesis with Pdr1-mediated regulation of azole resistance is crucial for ensuring the continued efficacy of azole drugs against
C. glabrata
.
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14
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Gu Y, Jiao X, Ye L, Yu H. Metabolic engineering strategies for de novo biosynthesis of sterols and steroids in yeast. BIORESOUR BIOPROCESS 2021; 8:110. [PMID: 38650187 PMCID: PMC10992410 DOI: 10.1186/s40643-021-00460-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 10/16/2021] [Indexed: 12/17/2022] Open
Abstract
Steroidal compounds are of great interest in the pharmaceutical field, with steroidal drugs as the second largest category of medicine in the world. Advances in synthetic biology and metabolic engineering have enabled de novo biosynthesis of sterols and steroids in yeast, which is a green and safe production route for these valuable steroidal compounds. In this review, we summarize the metabolic engineering strategies developed and employed for improving the de novo biosynthesis of sterols and steroids in yeast based on the regulation mechanisms, and introduce the recent progresses in de novo synthesis of some typical sterols and steroids in yeast. The remaining challenges and future perspectives are also discussed.
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Affiliation(s)
- Yuehao Gu
- Key Laboratory of Biomass Chemical Engineering (Education Ministry), College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Xue Jiao
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Lidan Ye
- Key Laboratory of Biomass Chemical Engineering (Education Ministry), College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
| | - Hongwei Yu
- Key Laboratory of Biomass Chemical Engineering (Education Ministry), College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
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15
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Vu BG, Stamnes MA, Li Y, Rogers PD, Moye-Rowley WS. The Candida glabrata Upc2A transcription factor is a global regulator of antifungal drug resistance pathways. PLoS Genet 2021; 17:e1009582. [PMID: 34591857 PMCID: PMC8509923 DOI: 10.1371/journal.pgen.1009582] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/12/2021] [Accepted: 09/22/2021] [Indexed: 01/15/2023] Open
Abstract
The most commonly used antifungal drugs are the azole compounds, which interfere with biosynthesis of the fungal-specific sterol: ergosterol. The pathogenic yeast Candida glabrata commonly acquires resistance to azole drugs like fluconazole via mutations in a gene encoding a transcription factor called PDR1. These PDR1 mutations lead to overproduction of drug transporter proteins like the ATP-binding cassette transporter Cdr1. In other Candida species, mutant forms of a transcription factor called Upc2 are associated with azole resistance, owing to the important role of this protein in control of expression of genes encoding enzymes involved in the ergosterol biosynthetic pathway. Recently, the C. glabrata Upc2A factor was demonstrated to be required for normal azole resistance, even in the presence of a hyperactive mutant form of PDR1. Using genome-scale approaches, we define the network of genes bound and regulated by Upc2A. By analogy to a previously described hyperactive UPC2 mutation found in Saccharomyces cerevisiae, we generated a similar form of Upc2A in C. glabrata called G898D Upc2A. Analysis of Upc2A genomic binding sites demonstrated that wild-type Upc2A binding to target genes was strongly induced by fluconazole while G898D Upc2A bound similarly, irrespective of drug treatment. Transcriptomic analyses revealed that, in addition to the well-described ERG genes, a large group of genes encoding components of the translational apparatus along with membrane proteins were responsive to Upc2A. These Upc2A-regulated membrane protein-encoding genes are often targets of the Pdr1 transcription factor, demonstrating the high degree of overlap between these two regulatory networks. Finally, we provide evidence that Upc2A impacts the Pdr1-Cdr1 system and also modulates resistance to caspofungin. These studies provide a new perspective of Upc2A as a master regulator of lipid and membrane protein biosynthesis. In the pathogenic yeast Candida glabrata, expression of the genes encoding enzymes in the ergosterol biosynthetic pathway is controlled by the transcription factor Upc2A. C. glabrata has a low intrinsic susceptibility to azole therapy and acquires fluconazole resistance at high frequency. These azole resistant mutants typically contain substitution mutations in a gene encoding the transcription factor Pdr1. Pdr1 does not appear to regulate ergosterol genes and instead induces expression of genes encoding drug transport proteins like CDR1. Here we establish that extensive overlap exists between the regulatory networks defined by Upc2A and Pdr1. Genomic approaches are used to describe the hundreds of genes regulated by Upc2A that far exceed the well-described impact of this factor on genes involved in ergosterol biosynthesis. The overlap between Upc2A and Pdr1 is primarily described by co-regulation of genes encoding membrane transporters like CDR1. We provide evidence that Upc2A impacts the transcriptional control of the FKS1 gene, producing a target of a second major class of antifungal drugs, the echinocandins. Our data are consistent with Upc2A playing a role as a master regulator coordinating the synthesis of membrane structural components, both at the level of lipids and proteins, to produce properly functional biological membranes.
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Affiliation(s)
- Bao Gia Vu
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Mark A. Stamnes
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Yu Li
- Department of Clinical Pharmacy and Translational Science, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - P. David Rogers
- Department of Clinical Pharmacy and Translational Science, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - W. Scott Moye-Rowley
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- * E-mail:
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16
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Kern AF, Yang GX, Khosla NM, Ang RML, Snyder MP, Fraser HB. Divergent patterns of selection on metabolite levels and gene expression. BMC Ecol Evol 2021; 21:185. [PMID: 34587900 PMCID: PMC8482673 DOI: 10.1186/s12862-021-01915-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 09/06/2021] [Indexed: 11/19/2022] Open
Abstract
Background Natural selection can act on multiple genes in the same pathway, leading to polygenic adaptation. For example, adaptive changes were found to down-regulate six genes involved in ergosterol biosynthesis—an essential pathway targeted by many antifungal drugs—in some strains of the yeast Saccharomyces cerevisiae. However, the impact of this polygenic adaptation on metabolite levels was unknown. Here, we performed targeted mass spectrometry to measure the levels of eight metabolites in this pathway in 74 yeast strains from a genetic cross. Results Through quantitative trait locus (QTL) mapping we identified 19 loci affecting ergosterol pathway metabolite levels, many of which overlap loci that also impact gene expression within the pathway. We then used the recently developed v-test, which identified selection acting upon three metabolite levels within the pathway, none of which were predictable from the gene expression adaptation. Conclusions These data showed that effects of selection on metabolite levels were complex and not predictable from gene expression data. This suggests that a deeper understanding of metabolism is necessary before we can understand the impacts of even relatively straightforward gene expression adaptations on metabolic pathways. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-021-01915-5.
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Affiliation(s)
| | | | - Neil M Khosla
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Roy Moh Lik Ang
- Department of Genetics, Stanford University, Stanford, CA, USA
| | | | - Hunter B Fraser
- Department of Biology, Stanford University, Stanford, CA, USA.
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17
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Modular and Molecular Optimization of a LOV (Light-Oxygen-Voltage)-Based Optogenetic Switch in Yeast. Int J Mol Sci 2021; 22:ijms22168538. [PMID: 34445244 PMCID: PMC8395189 DOI: 10.3390/ijms22168538] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 07/27/2021] [Accepted: 07/27/2021] [Indexed: 01/25/2023] Open
Abstract
Optogenetic switches allow light-controlled gene expression with reversible and spatiotemporal resolution. In Saccharomyces cerevisiae, optogenetic tools hold great potential for a variety of metabolic engineering and biotechnology applications. In this work, we report on the modular optimization of the fungal light-oxygen-voltage (FUN-LOV) system, an optogenetic switch based on photoreceptors from the fungus Neurospora crassa. We also describe new switch variants obtained by replacing the Gal4 DNA-binding domain (DBD) of FUN-LOV with nine different DBDs from yeast transcription factors of the zinc cluster family. Among the tested modules, the variant carrying the Hap1p DBD, which we call "HAP-LOV", displayed higher levels of luciferase expression upon induction compared to FUN-LOV. Further, the combination of the Hap1p DBD with either p65 or VP16 activation domains also resulted in higher levels of reporter expression compared to the original switch. Finally, we assessed the effects of the plasmid copy number and promoter strength controlling the expression of the FUN-LOV and HAP-LOV components, and observed that when low-copy plasmids and strong promoters were used, a stronger response was achieved in both systems. Altogether, we describe a new set of blue-light optogenetic switches carrying different protein modules, which expands the available suite of optogenetic tools in yeast and can additionally be applied to other systems.
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18
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Sun ZJ, Lian JZ, Zhu L, Jiang YQ, Li GS, Xue HL, Wu MB, Yang LR, Lin JP. Combined Biosynthetic Pathway Engineering and Storage Pool Expansion for High-Level Production of Ergosterol in Industrial Saccharomyces cerevisiae. Front Bioeng Biotechnol 2021; 9:681666. [PMID: 34268298 PMCID: PMC8275991 DOI: 10.3389/fbioe.2021.681666] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/07/2021] [Indexed: 11/25/2022] Open
Abstract
Ergosterol, a terpenoid compound produced by fungi, is an economically important metabolite serving as the direct precursor of steroid drugs. Herein, ergsosterol biosynthetic pathway modification combined with storage capacity enhancement was proposed to synergistically improve the production of ergosterol in Saccharomyces cerevisiae. S. cerevisiae strain S1 accumulated the highest amount of ergosterol [7.8 mg/g dry cell weight (DCW)] among the wild-type yeast strains tested and was first selected as the host for subsequent metabolic engineering studies. Then, the push and pull of ergosterol biosynthesis were engineered to increase the metabolic flux, overexpression of the sterol acyltransferase gene ARE2 increased ergosterol content to 10 mg/g DCW and additional overexpression of a global regulatory factor allele (UPC2-1) increased the ergosterol content to 16.7 mg/g DCW. Furthermore, considering the hydrophobicity sterol esters and accumulation in lipid droplets, the fatty acid biosynthetic pathway was enhanced to expand the storage pool for ergosterol. Overexpression of ACC1 coding for the acetyl-CoA carboxylase increased ergosterol content from 16.7 to 20.7 mg/g DCW. To address growth inhibition resulted from premature accumulation of ergosterol, auto-inducible promoters were employed to dynamically control the expression of ARE2, UPC2-1, and ACC1. Consequently, better cell growth led to an increase of ergosterol content to 40.6 mg/g DCW, which is 4.2-fold higher than that of the starting strain. Finally, a two-stage feeding strategy was employed for high-density cell fermentation, with an ergosterol yield of 2986.7 mg/L and content of 29.5 mg/g DCW. This study provided an effective approach for the production of ergosterol and other related terpenoid molecules.
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Affiliation(s)
- Zhi-Jiao Sun
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Jia-Zhang Lian
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Li Zhu
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Yi-Qi Jiang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Guo-Si Li
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Hai-Long Xue
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Mian-Bin Wu
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Li-Rong Yang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Jian-Ping Lin
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
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19
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Pereira R, Ishchuk OP, Li X, Liu Q, Liu Y, Otto M, Chen Y, Siewers V, Nielsen J. Metabolic Engineering of Yeast. Metab Eng 2021. [DOI: 10.1002/9783527823468.ch18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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20
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Godinho CP, Costa R, Sá‐Correia I. The ABC transporter Pdr18 is required for yeast thermotolerance due to its role in ergosterol transport and plasma membrane properties. Environ Microbiol 2021; 23:69-80. [PMID: 32985771 PMCID: PMC7891575 DOI: 10.1111/1462-2920.15253] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/24/2020] [Indexed: 12/19/2022]
Abstract
Among the mechanisms by which yeast overcomes multiple stresses is the expression of genes encoding ATP-binding cassette (ABC) transporters required for resistance to a wide range of toxic compounds. These substrates may include weak acids, alcohols, agricultural pesticides, polyamines, metal cations, as in the case of Pdr18. This pleotropic drug resistance transporter was previously proposed to transport ergosterol at the plasma membrane (PM) level contributing to the maintenance of PM lipid organization and reduced diffusional permeation induced by lipophilic compounds. The present work reports a novel phenotype associated with the putative drug/xenobiotic-efflux-pump transporter Pdr18: the resistance to heat shock and to long-term growth at supra-optimal temperatures. Cultivation at 40°C was demonstrated to lead to higher PM permeabilization of a pdr18Δ cell population with the PDR18 gene deleted compared with the parental strain population, as indicated by flow cytometry analysis of propidium iodide stained cells. Cells of pdr18Δ grown at 40°C also exhibited increased transcription levels from genes of the ergosterol biosynthetic pathway, compared with parental cells. However, this adaptive response at 40°C was not enough to maintain PM physiological ergosterol levels in the population lacking the Pdr18 transporter and free ergosterol precursors accumulate in the deletion mutant cells.
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Affiliation(s)
- Cláudia P. Godinho
- iBB ‐ Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de LisboaLisbonPortugal
| | - Rute Costa
- iBB ‐ Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de LisboaLisbonPortugal
- Department of BioengineeringInstituto Superior Técnico, Universidade de LisboaLisbonPortugal
| | - Isabel Sá‐Correia
- iBB ‐ Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de LisboaLisbonPortugal
- Department of BioengineeringInstituto Superior Técnico, Universidade de LisboaLisbonPortugal
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21
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Gutierrez-Armijos R, Sussmann RAC, Silber AM, Cortez M, Hernandez A. Abnormal sterol-induced cell wall glucan deficiency in yeast is due to impaired glucan synthase transport to the plasma membrane. Biochem J 2020; 477:BCJ20200663. [PMID: 33094814 DOI: 10.1042/bcj20200663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/18/2020] [Accepted: 10/22/2020] [Indexed: 01/01/2023]
Abstract
Abnormal sterols disrupt cellular functions through yet unclear mechanisms. In Saccharomyces cerevisiae, accumulation of Δ8-sterols, the same type of sterols observed in patients of Conradi-Hünermann-Happle syndrome or in fungi after amine fungicide treatment, leads to cell wall weakness. We have studied the influence of Δ8-sterols on the activity of glucan synthase I, the protein synthetizing the main polymer in fungal cell walls, its regulation by the Cell Wall Integrity (CWI) pathway, and its transport from the endoplasmic reticulum to the plasma membrane. We ascertained that the catalytic characteristics were mostly unaffected by the presence of abnormal sterols but the enzyme was partially retained in the endoplasmic reticulum, leading to glucan deficit at the cell wall. Furthermore, we observed that glucan synthase I traveled through an unconventional exocytic route to the plasma membrane that is associated with low density intracellular membranes. Also, we found out that the CWI pathway remained inactive despite low glucan levels at the cell wall. Taken together, these data suggest that Δ8-sterols affect cell walls by inhibiting unconventional secretion of proteins leading to retention and degradation of glucan synthase I, while the compensatory CWI pathway is unable to activate. These results could be instrumental to understand defects of bone development in cholesterol biosynthesis disorders and fungicide mechanisms of action.
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Regulation of Ergosterol Biosynthesis in Saccharomyces cerevisiae. Genes (Basel) 2020; 11:genes11070795. [PMID: 32679672 PMCID: PMC7397035 DOI: 10.3390/genes11070795] [Citation(s) in RCA: 175] [Impact Index Per Article: 43.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/06/2020] [Accepted: 07/13/2020] [Indexed: 12/14/2022] Open
Abstract
Ergosterol is an essential component of fungal cell membranes that determines the fluidity, permeability and activity of membrane-associated proteins. Ergosterol biosynthesis is a complex and highly energy-consuming pathway that involves the participation of many enzymes. Deficiencies in sterol biosynthesis cause pleiotropic defects that limit cellular proliferation and adaptation to stress. Thereby, fungal ergosterol levels are tightly controlled by the bioavailability of particular metabolites (e.g., sterols, oxygen and iron) and environmental conditions. The regulation of ergosterol synthesis is achieved by overlapping mechanisms that include transcriptional expression, feedback inhibition of enzymes and changes in their subcellular localization. In the budding yeast Saccharomyces cerevisiae, the sterol regulatory element (SRE)-binding proteins Upc2 and Ecm22, the heme-binding protein Hap1 and the repressor factors Rox1 and Mot3 coordinate ergosterol biosynthesis (ERG) gene expression. Here, we summarize the sterol biosynthesis, transport and detoxification systems of S. cerevisiae, as well as its adaptive response to sterol depletion, low oxygen, hyperosmotic stress and iron deficiency. Because of the large number of ERG genes and the crosstalk between different environmental signals and pathways, many aspects of ergosterol regulation are still unknown. The study of sterol metabolism and its regulation is highly relevant due to its wide applications in antifungal treatments, as well as in food and pharmaceutical industries.
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Bhattacharya S, Sae-Tia S, Fries BC. Candidiasis and Mechanisms of Antifungal Resistance. Antibiotics (Basel) 2020; 9:antibiotics9060312. [PMID: 32526921 PMCID: PMC7345657 DOI: 10.3390/antibiotics9060312] [Citation(s) in RCA: 200] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/06/2020] [Accepted: 06/07/2020] [Indexed: 12/13/2022] Open
Abstract
Candidiasis can be present as a cutaneous, mucosal or deep-seated organ infection, which is caused by more than 20 types of Candida sp., with C. albicans being the most common. These are pathogenic yeast and are usually present in the normal microbiome. High-risk individuals are patients of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), organ transplant, and diabetes. During infection, pathogens can adhere to complement receptors and various extracellular matrix proteins in the oral and vaginal cavity. Oral and vaginal Candidiasis results from the overgrowth of Candida sp. in the hosts, causing penetration of the oral and vaginal tissues. Symptoms include white patches in the mouth, tongue, throat, and itchiness or burning of genitalia. Diagnosis involves visual examination, microscopic analysis, or culturing. These infections are treated with a variety of antifungals that target different biosynthetic pathways of the pathogen. For example, echinochandins target cell wall biosynthesis, while allylamines, azoles, and morpholines target ergosterol biosynthesis, and 5-Flucytosine (5FC) targets nucleic acid biosynthesis. Azoles are commonly used in therapeutics, however, because of its fungistatic nature, Candida sp. evolve azole resistance. Besides azoles, Candida sp. also acquire resistance to polyenes, echinochandins, and 5FC. This review discusses, in detail, the drug resistance mechanisms adapted by Candida sp.
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Affiliation(s)
- Somanon Bhattacharya
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, New York, NY 11794, USA; (S.S.-T.); (B.C.F.)
- Correspondence:
| | - Sutthichai Sae-Tia
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, New York, NY 11794, USA; (S.S.-T.); (B.C.F.)
| | - Bettina C. Fries
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, New York, NY 11794, USA; (S.S.-T.); (B.C.F.)
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, NY 11794, USA
- Veterans Administration Medical Center, Northport, New York, NY 11768, USA
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Kwak S, Yun EJ, Lane S, Oh EJ, Kim KH, Jin YS. Redirection of the Glycolytic Flux Enhances Isoprenoid Production in Saccharomyces cerevisiae. Biotechnol J 2019; 15:e1900173. [PMID: 31466140 DOI: 10.1002/biot.201900173] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 08/08/2019] [Indexed: 01/07/2023]
Abstract
Sufficient supply of reduced nicotinamide adenine dinucleotide phosphate (NADPH) is a prerequisite of the overproduction of isoprenoids and related bioproducts in Saccharomyces cerevisiae. Although S. cerevisiae highly depends on the oxidative pentose phosphate (PP) pathway to produce NADPH, its metabolic flux toward the oxidative PP pathway is limited due to the rigid glycolysis flux. To maximize NADPH supply for the isoprenoid production in yeast, upper glycolytic metabolic fluxes are reduced by introducing mutations into phosphofructokinase (PFK) along with overexpression of ZWF1 encoding glucose-6-phosphate (G6P) dehydrogenase. The PFK mutations (Pfk1 S724D and Pfk2 S718D) result in less glycerol production and more accumulation of G6P, which is a gateway metabolite toward the oxidative PP pathway. When combined with the PFK mutations, overexpression of ZWF1 caused substantial increases of [NADPH]/[NADP+ ] ratios whereas the effect of ZWF1 overexpression alone in the wild-type strain is not noticeable. Also, the introduction of ZWF1 overexpression and the PFK mutations into engineered yeast overexpressing acetyl-CoA C-acetyltransferase (ERG10), truncated HMG-CoA reductase isozyme 1 (tHMG1), and amorphadiene synthase (ADS) leads to a titer of 497 mg L-1 of amorphadiene (3.7-fold over the parental strain). These results suggest that perturbation of upper glycolytic fluxes, in addition to ZWF1 overexpression, is necessary for efficient NADPH supply through the oxidative PP pathway and enhanced production of isoprenoids by engineered S. cerevisiae.
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Affiliation(s)
- Suryang Kwak
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Eun Ju Yun
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Department of Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Stephan Lane
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Eun Joong Oh
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Kyoung Heon Kim
- Department of Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
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25
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Arhar S, Natter K. Common aspects in the engineering of yeasts for fatty acid- and isoprene-based products. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:158513. [PMID: 31465888 DOI: 10.1016/j.bbalip.2019.08.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 06/26/2019] [Accepted: 08/20/2019] [Indexed: 11/18/2022]
Abstract
The biosynthetic pathways for most lipophilic metabolites share several common principles. These substances are built almost exclusively from acetyl-CoA as the donor for the carbon scaffold and NADPH is required for the reductive steps during biosynthesis. Due to their hydrophobicity, the end products are sequestered into the same cellular compartment, the lipid droplet. In this review, we will summarize the efforts in the metabolic engineering of yeasts for the production of two major hydrophobic substance classes, fatty acid-based lipids and isoprenoids, with regard to these common aspects. We will compare and discuss the results of genetic engineering strategies to construct strains with enhanced synthesis of the precursor acetyl-CoA and with modified redox metabolism for improved NADPH supply. We will also discuss the role of the lipid droplet in the storage of the hydrophobic product and review the strategies to either optimize this organelle for higher capacity or to achieve excretion of the product into the medium.
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Affiliation(s)
- Simon Arhar
- Institute of Molecular Biosciences, NAWI Graz, University of Graz, Humboldtstrasse 50/II, 8010 Graz, Austria
| | - Klaus Natter
- Institute of Molecular Biosciences, NAWI Graz, University of Graz, Humboldtstrasse 50/II, 8010 Graz, Austria.
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26
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Transcriptomic Response of Saccharomyces cerevisiae during Fermentation under Oleic Acid and Ergosterol Depletion. FERMENTATION-BASEL 2019. [DOI: 10.3390/fermentation5030057] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Under anaerobic/hypoxic conditions, Saccharomyces cerevisiae relies on external lipid supplements to modulate membrane lipid fraction in response to different stresses. Here, transcriptomic responses of two S. cerevisiae wine strains were evaluated during hypoxic fermentation of a synthetic must with/without ergosterol and oleic acid supplementation. In the absence of lipids, the two strains, namely EC1118 and M25, showed different behaviour, with M25 significantly decreasing its fermentation rate from the 72 h after inoculum. At this time point, the whole genome transcriptomic analysis revealed common and strain-specific responses to the lack of lipid supplementation. Common responses included the upregulation of the genes involved in ergosterol biosynthesis, as well as the seripauperin and the heat shock protein multigene families. In addition, the upregulation of the aerobic isoforms of genes involved in mitochondrial electron transport is compatible with the previously observed accumulation of reactive oxygen species in the two strains during growth in absence of lipids. Considering the strain-specific responses, M25 downregulated the transcription of genes involved in glucose transport, methionine biosynthesis and of those encoding mannoproteins required for adaptation to low temperatures and hypoxia. The identification of these pathways, which are presumably involved in yeast resistance to stresses, will assist industrial strain selection.
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A phosphorylated transcription factor regulates sterol biosynthesis in Fusarium graminearum. Nat Commun 2019; 10:1228. [PMID: 30874562 PMCID: PMC6420630 DOI: 10.1038/s41467-019-09145-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 02/20/2019] [Indexed: 11/08/2022] Open
Abstract
Sterol biosynthesis is controlled by transcription factor SREBP in many eukaryotes. Here, we show that SREBP orthologs are not involved in the regulation of sterol biosynthesis in Fusarium graminearum, a fungal pathogen of cereal crops worldwide. Instead, sterol production is controlled in this organism by a different transcription factor, FgSR, that forms a homodimer and binds to a 16-bp cis-element of its target gene promoters containing two conserved CGAA repeat sequences. FgSR is phosphorylated by the MAP kinase FgHog1, and the phosphorylated FgSR interacts with the chromatin remodeling complex SWI/SNF at the target genes, leading to enhanced transcription. Interestingly, FgSR orthologs exist only in Sordariomycetes and Leotiomycetes fungi. Additionally, FgSR controls virulence mainly via modulating deoxynivalenol biosynthesis and responses to phytoalexin.
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28
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Cirigliano A, Macone A, Bianchi MM, Oliaro-Bosso S, Balliano G, Negri R, Rinaldi T. Ergosterol reduction impairs mitochondrial DNA maintenance in S. cerevisiae. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:290-303. [DOI: 10.1016/j.bbalip.2018.12.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 11/27/2018] [Accepted: 12/10/2018] [Indexed: 12/20/2022]
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Wang SQ, Wang T, Liu JF, Deng L, Wang F. Overexpression of Ecm22 improves ergosterol biosynthesis in Saccharomyces cerevisiae. Lett Appl Microbiol 2018; 67:484-490. [PMID: 30098030 DOI: 10.1111/lam.13061] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 07/17/2018] [Accepted: 07/28/2018] [Indexed: 12/01/2022]
Abstract
Ergosterol biosynthesis in Saccharomyces cerevisiae is complex and the underlying mechanism of regulation remains unclear. To clarify the influence of transcriptional regulation on the ergosterol content, transcription factor Ecm22 was overexpressed in S. cerevisiae. Results showed that the overexpression of ECM22 led to an increased invasive growth. Fluconazole susceptibility testing indicated that strains overexpressing ECM22 could grow at 20 μg(fluconazole) ml-1 . By contrast, the control failed to grow at 16 μg(fluconazole) ml-1 . Among truncated ECM22 fragments, only the 1440-bp DNA fragment exerted almost the same impact on ergosterol content as that of the full-length gene. In a 5-l bioreactor, the highest ergosterol yield of the recombinant reached 32∙7 mg g(dry cell weight) -1 , which was increased by about 20% compared with that of the control. In this work, a novel approach for enhancing the ergosterol production by overexpressing a transcription factor in S. cerevisiae was developed.
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Affiliation(s)
- S-Q Wang
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - T Wang
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - J-F Liu
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - L Deng
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - F Wang
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
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30
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Guo XJ, Xiao WH, Wang Y, Yao MD, Zeng BX, Liu H, Zhao GR, Yuan YJ. Metabolic engineering of Saccharomyces cerevisiae for 7-dehydrocholesterol overproduction. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:192. [PMID: 30026807 PMCID: PMC6047132 DOI: 10.1186/s13068-018-1194-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 07/06/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND 7-Dehydrocholesterol (7-DHC) has attracted increasing attentions due to its great medical value and the enlarging market demand of its ultraviolet-catalyzed product vitamin D3. Microbial production of 7-DHC from simple carbon has been recognized as an attractive complement to the traditional sources. Even though our previous work realized 7-DHC biosynthesis in Saccharomyces cerevisiae, the current productivity of 7-DHC is still too low to satisfy the demand of following industrialization. As increasing the compatibility between heterologous pathway and host cell is crucial to realize microbial overproduction of natural products with complex structure and relative long pathway, in this study, combined efforts in tuning the heterologous Δ24-dehydrocholesterol reductase (DHCR24) and manipulating host cell were applied to promote 7-DHC accumulation. RESULTS In order to decouple 7-DHC production with cell growth, inducible GAL promoters was employed to control 7-DHC synthesis. Meanwhile, the precursor pool was increased via overexpressing all the mevalonate (MVA) pathway genes (ERG10, ERG13, tHMG1, ERG12, ERG8, ERG19, IDI1, ERG20). Through screening DHCR24s from eleven tested sources, it was found that DHCR24 from Gallus gallus (Gg_DHCR24) achieved the highest 7-DHC production. Then 7-DHC accumulation was increased by 27.5% through stepwise fine-tuning the transcription level of Gg_DHCR24 in terms of altering its induction strategy, integration position, and the used promoter. By blocking the competitive path (ΔERG6) and supplementing another copy of Gg_DHCR24 in locus ERG6, 7-DHC accumulation was further enhanced by 1.07-fold. Afterward, 7-DHC production was improved by 48.3% (to 250.8 mg/L) by means of deleting NEM1 that was involved in lipids metabolism. Eventually, 7-DHC production reached to 1.07 g/L in 5-L bioreactor, which is the highest reported microbial titer as yet known. CONCLUSIONS Combined engineering of the pathway and the host cell was adopted in this study to boost 7-DHC output in the yeast. 7-DHC titer was stepwise improved by 26.9-fold compared with the starting strain. This work not only opens large opportunities to realize downstream de novo synthesis of other steroids, but also highlights the importance of the combinatorial engineering of heterologous pathway and host to obtain microbial overproduction of many other natural products.
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Affiliation(s)
- Xiao-Jing Guo
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical & Engineering, Tianjin University, No. 92, Weijin Road, Nankai District, Tianjin, 300072 People’s Republic of China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Wen-Hai Xiao
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical & Engineering, Tianjin University, No. 92, Weijin Road, Nankai District, Tianjin, 300072 People’s Republic of China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Ying Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical & Engineering, Tianjin University, No. 92, Weijin Road, Nankai District, Tianjin, 300072 People’s Republic of China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Ming-Dong Yao
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical & Engineering, Tianjin University, No. 92, Weijin Road, Nankai District, Tianjin, 300072 People’s Republic of China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Bo-Xuan Zeng
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical & Engineering, Tianjin University, No. 92, Weijin Road, Nankai District, Tianjin, 300072 People’s Republic of China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Hong Liu
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical & Engineering, Tianjin University, No. 92, Weijin Road, Nankai District, Tianjin, 300072 People’s Republic of China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Guang-Rong Zhao
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical & Engineering, Tianjin University, No. 92, Weijin Road, Nankai District, Tianjin, 300072 People’s Republic of China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Ying-Jin Yuan
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical & Engineering, Tianjin University, No. 92, Weijin Road, Nankai District, Tianjin, 300072 People’s Republic of China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072 People’s Republic of China
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Kotopka BJ, Li Y, Smolke CD. Synthetic biology strategies toward heterologous phytochemical production. Nat Prod Rep 2018; 35:902-920. [DOI: 10.1039/c8np00028j] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
This review summarizes the recent progress in heterologous phytochemical biosynthetic pathway reconstitution in plant, bacteria, and yeast, with a focus on the synthetic biology strategies applied in these engineering efforts.
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Affiliation(s)
| | - Yanran Li
- Department of Chemical and Environmental Engineering
- Riverside
- USA
| | - Christina D. Smolke
- Department of Bioengineering
- Stanford University
- Stanford
- USA
- Chan Zuckerberg Biohub
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A Novel Sterol-Signaling Pathway Governs Azole Antifungal Drug Resistance and Hypoxic Gene Repression in Saccharomyces cerevisiae. Genetics 2017; 208:1037-1055. [PMID: 29263028 DOI: 10.1534/genetics.117.300554] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 12/19/2017] [Indexed: 12/26/2022] Open
Abstract
During antifungal drug treatment and hypoxia, genetic and epigenetic changes occur to maintain sterol homeostasis and cellular function. In this study, we show that SET domain-containing epigenetic factors govern drug efficacy to the medically relevant azole class of antifungal drugs. Upon this discovery, we determined that Set4 is induced when Saccharomyces cerevisiae are treated with azole drugs or grown under hypoxic conditions; two conditions that deplete cellular ergosterol and increase sterol precursors. Interestingly, Set4 induction is controlled by the sterol-sensing transcription factors, Upc2 and Ecm22 To determine the role of Set4 on gene expression under hypoxic conditions, we performed RNA-sequencing analysis and showed that Set4 is required for global changes in gene expression. Specifically, loss of Set4 led to an upregulation of nearly all ergosterol genes, including ERG11 and ERG3, suggesting that Set4 functions in gene repression. Furthermore, mass spectrometry analysis revealed that Set4 interacts with the hypoxic-specific transcriptional repressor, Hap1, where this interaction is necessary for Set4 recruitment to ergosterol gene promoters under hypoxia. Finally, an erg3Δ strain, which produces precursor sterols but lacks ergosterol, expresses Set4 under untreated aerobic conditions. Together, our data suggest that sterol precursors are needed for Set4 induction through an Upc2-mediated mechanism. Overall, this new sterol-signaling pathway governs azole antifungal drug resistance and mediates repression of sterol genes under hypoxic conditions.
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In vitro and in vivo antifungal activities and mechanism of heteropolytungstates against Candida species. Sci Rep 2017; 7:16942. [PMID: 29209074 PMCID: PMC5717275 DOI: 10.1038/s41598-017-17239-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 11/22/2017] [Indexed: 11/21/2022] Open
Abstract
The antifungal activities of heteropolytungstates, α-1,2,3-K6H[SiW9V3O40] (SiW-3), K13[Ce(SiW11O39)2]·17H2O (SiW-5), K13[Eu(SiW11O39)2]·25H2O (SiW-10), K6PV3W9O40 (PW-6), α-K4PVW11O40 (PW-8), were screened in 29 Candida albicans, 8 Candida glabrata, 3 Candida krusei, 2 Candida parapsilosis, 1 Candida tropicalis, and 1 Cryptococcus neoformans strains using the CLSI M27-A3 method. SiW-5 had the highest efficacy with a minimum inhibitory concentration (MIC) values of <0.2–10.2 μM in vitro. The antifungal mechanism, acute toxicity and in vivo antifungal activity of SiW-5 were then evaluated in C. albicans. The results showed that SiW-5 damaged the fungal cell membrane, reduce the ergosterol content and its main mode of action was through inhibition of ergosterol biosynthesis. Real-time PCR showed that ERG1, ERG7, ERG11 and ERG28 were all significantly upregulated by SiW-5. An acute toxicity study showed the 50% lethal dose (LD50) of SiW-5 for ICR mice was 1651.5 mg/kg. And in vivo antifungal studies demonstrated that SiW-5 reduced both the morbidity and fungal burden of mice infected with C. albicans. This study demonstrates that SiW-5 is a potential antifungal candidate against the Candida species.
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34
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Höfken T. Ecm22 and Upc2 regulate yeast mating through control of expression of the mating genes PRM1 and PRM4. Biochem Biophys Res Commun 2017; 493:1485-1490. [DOI: 10.1016/j.bbrc.2017.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 10/01/2017] [Indexed: 10/18/2022]
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35
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Wu G, Xu Z, Jönsson LJ. Profiling of Saccharomyces cerevisiae transcription factors for engineering the resistance of yeast to lignocellulose-derived inhibitors in biomass conversion. Microb Cell Fact 2017; 16:199. [PMID: 29137634 PMCID: PMC5686817 DOI: 10.1186/s12934-017-0811-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 11/04/2017] [Indexed: 11/24/2022] Open
Abstract
Background Yeast transcription factors (TFs) involved in the regulation of multidrug resistance (MDR) were investigated in experiments with deletion mutants, transformants overexpressing synthetic genes encoding TFs, and toxic concentrations of lignocellulose-derived substances added to cultures as complex mixtures or as specific compounds, viz. coniferyl aldehyde, 5-hydroxymethylfurfural, and furfural. Results In the presence of complex mixtures of toxic substances from spruce wood, transformants overexpressing YAP1 and STB5, TFs involved in oxidative stress response, exhibited enhanced relative growth rates amounting to 4.589 ± 0.261 and 1.455 ± 0.185, respectively. Other TFs identified as important for resistance included DAL81, GZF3, LEU3, PUT3, and WAR1. Potential overlapping functions of YAP1 and STB5 were investigated in experiments with permutations of deletions and overexpression of the two genes. YAP1 complemented STB5 with respect to resistance to 5-hydroxymethylfurfural, but had a distinct role with regard to resistance to coniferyl aldehyde as deletion of YAP1 rendered the cell incapable of resisting coniferyl aldehyde even if STB5 was overexpressed. Conclusions We have investigated 30 deletion mutants and eight transformants overexpressing MDR transcription factors with regard to the roles the transcription factors play in the resistance to toxic concentrations of lignocellulose-derived substances. This work provides an overview of the involvement of thirty transcription factors in the resistance to lignocellulose-derived substances, shows distinct and complementary roles played by YAP1 and STB5, and offers directions for the engineering of robust yeast strains for fermentation processes based on lignocellulosic feedstocks.![]() Electronic supplementary material The online version of this article (10.1186/s12934-017-0811-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Guochao Wu
- Department of Chemistry, Umeå University, 901 87, Umeå, Sweden.
| | - Zixiang Xu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Leif J Jönsson
- Department of Chemistry, Umeå University, 901 87, Umeå, Sweden
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36
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Kwak S, Kim SR, Xu H, Zhang GC, Lane S, Kim H, Jin YS. Enhanced isoprenoid production from xylose by engineeredSaccharomyces cerevisiae. Biotechnol Bioeng 2017; 114:2581-2591. [DOI: 10.1002/bit.26369] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 05/23/2017] [Accepted: 06/26/2017] [Indexed: 11/12/2022]
Affiliation(s)
- Suryang Kwak
- Department of Food Science and Human Nutrition; University of Illinois at Urbana-Champaign; Urbana Illinois
- Carl R. Woese Institute for Genomic Biology; University of Illinois at Urbana-Champaign; Urbana Illinois
| | - Soo Rin Kim
- School of Food Science and Biotechnology; Kyungpook National University; Daegu Republic of Korea
| | - Haiqing Xu
- Department of Food Science and Human Nutrition; University of Illinois at Urbana-Champaign; Urbana Illinois
- Carl R. Woese Institute for Genomic Biology; University of Illinois at Urbana-Champaign; Urbana Illinois
| | - Guo-Chang Zhang
- Carl R. Woese Institute for Genomic Biology; University of Illinois at Urbana-Champaign; Urbana Illinois
| | - Stephan Lane
- Department of Food Science and Human Nutrition; University of Illinois at Urbana-Champaign; Urbana Illinois
- Carl R. Woese Institute for Genomic Biology; University of Illinois at Urbana-Champaign; Urbana Illinois
| | - Heejin Kim
- Department of Food Science and Human Nutrition; University of Illinois at Urbana-Champaign; Urbana Illinois
- Carl R. Woese Institute for Genomic Biology; University of Illinois at Urbana-Champaign; Urbana Illinois
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition; University of Illinois at Urbana-Champaign; Urbana Illinois
- Carl R. Woese Institute for Genomic Biology; University of Illinois at Urbana-Champaign; Urbana Illinois
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Joshua IM, Höfken T. From Lipid Homeostasis to Differentiation: Old and New Functions of the Zinc Cluster Proteins Ecm22, Upc2, Sut1 and Sut2. Int J Mol Sci 2017; 18:ijms18040772. [PMID: 28379181 PMCID: PMC5412356 DOI: 10.3390/ijms18040772] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 03/27/2017] [Accepted: 03/31/2017] [Indexed: 12/27/2022] Open
Abstract
Zinc cluster proteins are a large family of transcriptional regulators with a wide range of biological functions. The zinc cluster proteins Ecm22, Upc2, Sut1 and Sut2 have initially been identified as regulators of sterol import in the budding yeast Saccharomyces cerevisiae. These proteins also control adaptations to anaerobic growth, sterol biosynthesis as well as filamentation and mating. Orthologs of these zinc cluster proteins have been identified in several species of Candida. Upc2 plays a critical role in antifungal resistance in these important human fungal pathogens. Upc2 is therefore an interesting potential target for novel antifungals. In this review we discuss the functions, mode of actions and regulation of Ecm22, Upc2, Sut1 and Sut2 in budding yeast and Candida.
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Affiliation(s)
| | - Thomas Höfken
- Division of Biosciences, Brunel University London, Uxbridge UB8 3PH, UK.
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An endoplasmic reticulum-engineered yeast platform for overproduction of triterpenoids. Metab Eng 2017; 40:165-175. [DOI: 10.1016/j.ymben.2017.02.007] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/13/2017] [Accepted: 02/14/2017] [Indexed: 11/23/2022]
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Identification of Yeast Mutants Exhibiting Altered Sensitivity to Valinomycin and Nigericin Demonstrate Pleiotropic Effects of Ionophores on Cellular Processes. PLoS One 2016; 11:e0164175. [PMID: 27711131 PMCID: PMC5053447 DOI: 10.1371/journal.pone.0164175] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 09/21/2016] [Indexed: 01/04/2023] Open
Abstract
Ionophores such as valinomycin and nigericin are potent tools for studying the impact of ion perturbance on cellular functions. To obtain a broader picture about molecular components involved in mediating the effects of these drugs on yeast cells under respiratory growth conditions, we performed a screening of the haploid deletion mutant library covering the Saccharomyces cerevisiae nonessential genes. We identified nearly 130 genes whose absence leads either to resistance or to hypersensitivity to valinomycin and/or nigericin. The processes affected by their protein products range from mitochondrial functions through ribosome biogenesis and telomere maintenance to vacuolar biogenesis and stress response. Comparison of the results with independent screenings performed by our and other laboratories demonstrates that although mitochondria might represent the main target for both ionophores, cellular response to the drugs is very complex and involves an intricate network of proteins connecting mitochondria, vacuoles, and other membrane compartments.
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Improving monoterpene geraniol production through geranyl diphosphate synthesis regulation in Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2016; 100:4561-71. [PMID: 26883346 DOI: 10.1007/s00253-016-7375-1] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 01/05/2016] [Accepted: 02/02/2016] [Indexed: 10/22/2022]
Abstract
Monoterpenes have wide applications in the food, cosmetics, and medicine industries and have recently received increased attention as advanced biofuels. However, compared with sesquiterpenes, monoterpene production is still lagging in Saccharomyces cerevisiae. In this study, geraniol, a valuable acyclic monoterpene alcohol, was synthesized in S. cerevisiae. We evaluated three geraniol synthases in S. cerevisiae, and the geraniol synthase Valeriana officinalis (tVoGES), which lacked a plastid-targeting peptide, yielded the highest geraniol production. To improve geraniol production, synthesis of the precursor geranyl diphosphate (GPP) was regulated by comparing three specific GPP synthase genes derived from different plants and the endogenous farnesyl diphosphate synthase gene variants ERG20 (G) (ERG20 (K197G) ) and ERG20 (WW) (ERG20 (F96W-N127W) ), and controlling endogenous ERG20 expression, coupled with increasing the expression of the mevalonate pathway by co-overexpressing IDI1, tHMG1, and UPC2-1. The results showed that overexpressing ERG20 (WW) and strengthening the mevalonate pathway significantly improved geraniol production, while expressing heterologous GPP synthase genes or down-regulating endogenous ERG20 expression did not show positive effect. In addition, we constructed an Erg20p(F96W-N127W)-tVoGES fusion protein, and geraniol production reached 66.2 mg/L after optimizing the amino acid linker and the order of the proteins. The best strain yielded 293 mg/L geraniol in a fed-batch cultivation, a sevenfold improvement over the highest titer previously reported in an engineered S. cerevisiae strain. Finally, we showed that the toxicity of geraniol limited its production. The platform developed here can be readily used to synthesize other monoterpenes.
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Hernández A, Herrera-Palau R, Madroñal JM, Albi T, López-Lluch G, Perez-Castiñeira JR, Navas P, Valverde F, Serrano A. Vacuolar H(+)-Pyrophosphatase AVP1 is Involved in Amine Fungicide Tolerance in Arabidopsis thaliana and Provides Tridemorph Resistance in Yeast. FRONTIERS IN PLANT SCIENCE 2016; 7:85. [PMID: 26904057 PMCID: PMC4746327 DOI: 10.3389/fpls.2016.00085] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/17/2016] [Indexed: 05/12/2023]
Abstract
Amine fungicides are widely used as crop protectants. Their success is believed to be related to their ability to inhibit postlanosterol sterol biosynthesis in fungi, in particular sterol-Δ(8),Δ(7)-isomerases and sterol-Δ(14)-reductases, with a concomitant accumulation of toxic abnormal sterols. However, their actual cellular effects and mechanisms of death induction are still poorly understood. Paradoxically, plants exhibit a natural resistance to amine fungicides although they have similar enzymes in postcicloartenol sterol biosynthesis that are also susceptible to fungicide inhibition. A major difference in vacuolar ion homeostasis between plants and fungi is the presence of a dual set of primary proton pumps in the former (V-ATPase and H(+)-pyrophosphatase), but only the V-ATPase in the latter. Abnormal sterols affect the proton-pumping capacity of V-ATPases in fungi and this has been proposed as a major determinant in fungicide action. Using Saccharomyces cerevisiae as a model fungus, we provide evidence that amine fungicide treatment induced cell death by apoptosis. Cell death was concomitant with impaired H(+)-pumping capacity in vacuole vesicles and dependent on vacuolar proteases. Also, the heterologous expression of the Arabidopsis thaliana main H(+)-pyrophosphatase (AVP1) at the fungal vacuolar membrane reduced apoptosis levels in yeast and increased resistance to amine fungicides. Consistently, A. thaliana avp1 mutant seedlings showed increased susceptibility to this amine fungicide, particularly at the level of root development. This is in agreement with AVP1 being nearly the sole H(+)-pyrophosphatase gene expressed at the root elongation zones. All in all, the present data suggest that H(+)-pyrophosphatases are major determinants of plant tolerance to amine fungicides.
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Affiliation(s)
- Agustín Hernández
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas, Universidad de SevillaSevilla, Spain
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São PauloSão Paulo, Brazil
| | - Rosana Herrera-Palau
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas, Universidad de SevillaSevilla, Spain
| | - Juan M. Madroñal
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas, Universidad de SevillaSevilla, Spain
| | - Tomás Albi
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas, Universidad de SevillaSevilla, Spain
| | - Guillermo López-Lluch
- Centro Andaluz de Biología del Desarrollo and Centre of Biomedical Research in Rare Diseases, ISCIII, Consejo Superior de Investigaciones Científicas, Universidad Pablo de OlavideSevilla, Spain
| | - José R. Perez-Castiñeira
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas, Universidad de SevillaSevilla, Spain
| | - Plácido Navas
- Centro Andaluz de Biología del Desarrollo and Centre of Biomedical Research in Rare Diseases, ISCIII, Consejo Superior de Investigaciones Científicas, Universidad Pablo de OlavideSevilla, Spain
| | - Federico Valverde
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas, Universidad de SevillaSevilla, Spain
| | - Aurelio Serrano
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas, Universidad de SevillaSevilla, Spain
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Woods K, Höfken T. The zinc cluster proteins Upc2 and Ecm22 promote filamentation in Saccharomyces cerevisiae by sterol biosynthesis-dependent and -independent pathways. Mol Microbiol 2015; 99:512-27. [PMID: 26448198 DOI: 10.1111/mmi.13244] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2015] [Indexed: 12/31/2022]
Abstract
The transition between a unicellular yeast form to multicellular filaments is crucial for budding yeast foraging and the pathogenesis of many fungal pathogens such as Candida albicans. Here, we examine the role of the related transcription factors Ecm22 and Upc2 in Saccharomyces cerevisiae filamentation. Overexpression of either ECM22 or UPC2 leads to increased filamentation, whereas cells lacking both ECM22 and UPC2 do not exhibit filamentous growth. Ecm22 and Upc2 positively control the expression of FHN1, NPR1, PRR2 and sterol biosynthesis genes. These genes all play a positive role in filamentous growth, and their expression is upregulated during filamentation in an Ecm22/Upc2-dependent manner. Furthermore, ergosterol content increases during filamentous growth. UPC2 expression also increases during filamentation and is inhibited by the transcription factors Sut1 and Sut2. The expression of SUT1 and SUT2 in turn is under negative control of the transcription factor Ste12. We suggest that during filamentation Ste12 becomes activated and reduces SUT1/SUT2 expression levels. This would result in increased UPC2 levels and as a consequence to transcriptional activation of FHN1, NPR1, PRR2 and sterol biosynthesis genes. Higher ergosterol levels in combination with the proteins Fhn1, Npr1 and Prr2 would then mediate the transition to filamentous growth.
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Affiliation(s)
- Kelly Woods
- Division of Biosciences, Brunel University London, Uxbridge, UK
| | - Thomas Höfken
- Division of Biosciences, Brunel University London, Uxbridge, UK
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Function and Regulation of Cph2 in Candida albicans. EUKARYOTIC CELL 2015; 14:1114-26. [PMID: 26342020 DOI: 10.1128/ec.00102-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 08/31/2015] [Indexed: 01/03/2023]
Abstract
Candida albicans is associated with humans as both a harmless commensal organism and a pathogen. Cph2 is a transcription factor whose DNA binding domain is similar to that of mammalian sterol response element binding proteins (SREBPs). SREBPs are master regulators of cellular cholesterol levels and are highly conserved from fungi to mammals. However, ergosterol biosynthesis is regulated by the zinc finger transcription factor Upc2 in C. albicans and several other yeasts. Cph2 is not necessary for ergosterol biosynthesis but is important for colonization in the murine gastrointestinal (GI) tract. Here we demonstrate that Cph2 is a membrane-associated transcription factor that is processed to release the N-terminal DNA binding domain like SREBPs, but its cleavage is not regulated by cellular levels of ergosterol or oxygen. Chromatin immunoprecipitation sequencing (ChIP-seq) shows that Cph2 binds to the promoters of HMS1 and other components of the regulatory circuit for GI tract colonization. In addition, 50% of Cph2 targets are also bound by Hms1 and other factors of the regulatory circuit. Several common targets function at the head of the glycolysis pathway. Thus, Cph2 is an integral part of the regulatory circuit for GI colonization that regulates glycolytic flux. Transcriptome sequencing (RNA-seq) shows a significant overlap in genes differentially regulated by Cph2 and hypoxia, and Cph2 is important for optimal expression of some hypoxia-responsive genes in glycolysis and the citric acid cycle. We suggest that Cph2 and Upc2 regulate hypoxia-responsive expression in different pathways, consistent with a synthetic lethal defect of the cph2 upc2 double mutant in hypoxia.
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Hernández A, Serrano-Bueno G, Perez-Castiñeira JR, Serrano A. 8-Dehydrosterols induce membrane traffic and autophagy defects through V-ATPase dysfunction in Saccharomyces cerevisae. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:2945-56. [PMID: 26344037 DOI: 10.1016/j.bbamcr.2015.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 09/01/2015] [Indexed: 12/11/2022]
Abstract
8-Dehydrosterols are present in a wide range of biologically relevant situations, from human rare diseases to amine fungicide-treated fungi and crops. However, the molecular bases of their toxicity are still obscure. We show here that 8-dehydrosterols, but not other sterols, affect yeast vacuole acidification through V-ATPases. Moreover, erg2Δ cells display reductions in proton pumping rates consistent with ion-transport uncoupling in vitro. Concomitantly, subunit Vph1p shows conformational changes in the presence of 8-dehydrosterols. Expression of a plant vacuolar H(+)-pumping pyrophosphatase as an alternative H(+)-pump relieves Vma(-)-like phenotypes in erg2Δ-derived mutant cells. As a consequence of these acidification defects, endo- and exo-cytic traffic deficiencies that can be alleviated with a H(+)-pumping pyrophosphatase are also observed. Despite their effect on membrane traffic, 8-dehydrosterols do not induce endoplasmic reticulum stress or assembly defects on the V-ATPase. Autophagy is a V-ATPase dependent process and erg2Δ mutants accumulate autophagic bodies under nitrogen starvation similar to Vma(-) mutants. In contrast to classical Atg(-) mutants, this defect is not accompanied by impairment of traffic through the CVT pathway, processing of Pho8Δ60p, GFP-Atg8p localisation or difficulties to survive under nitrogen starvation conditions, but it is concomitant to reduced vacuolar protease activity. All in all, erg2Δ cells are autophagy mutants albeit some of their phenotypic features differ from classical Atg(-) defective cells. These results may pave the way to understand the aetiology of sterol-related diseases, the cytotoxic effect of amine fungicides, and may explain the tolerance to these compounds observed in plants.
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Affiliation(s)
- Agustín Hernández
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Avda Américo Vespucio 48, 41092 Sevilla, Spain.
| | - Gloria Serrano-Bueno
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Avda Américo Vespucio 48, 41092 Sevilla, Spain
| | - José Román Perez-Castiñeira
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Avda Américo Vespucio 48, 41092 Sevilla, Spain
| | - Aurelio Serrano
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Avda Américo Vespucio 48, 41092 Sevilla, Spain.
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Yang Q, Yin D, Yin Y, Cao Y, Ma Z. The response regulator BcSkn7 is required for vegetative differentiation and adaptation to oxidative and osmotic stresses in Botrytis cinerea. MOLECULAR PLANT PATHOLOGY 2015; 16:276-287. [PMID: 25130972 PMCID: PMC6638353 DOI: 10.1111/mpp.12181] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The high-osmolarity glycerol pathway plays an important role in the responses of fungi to various environmental stresses. Saccharomyces cerevisiae Skn7 is a response regulator in the high-osmolarity glycerol pathway, which regulates the oxidative stress response, cell cycle and cell wall biosynthesis. In this study, we characterized an Skn7 orthologue BcSkn7 in Botrytis cinerea. BcSKN7 can partly restore the growth defects of S. cerevisiae SKN7 mutant and vice versa. The BcSKN7 mutant (ΔBcSkn7-1) revealed increased sensitivity to ionic osmotic and oxidative stresses and to ergosterol biosynthesis inhibitors. In addition, ΔBcSkn7-1 was also impaired dramatically in conidiation and sclerotial formation. Western blot analysis showed that BcSkn7 positively regulated the phosphorylation of BcSak1 (the orthologue of S. cerevisiae Hog1) under osmotic stress, indicating that BcSkn7 is associated with the high-osmolarity glycerol pathway in B. cinerea. In contrast with BcSak1, BcSkn7 is not involved in the regulation of B. cinerea virulence. All of the phenotypic defects of ΔBcSkn7-1 are restored by genetic complementation of the mutant with the wild-type BcSKN7. The results of this study indicate that BcSkn7 plays an important role in the regulation of vegetative differentiation and in the response to various stresses in B. cinerea.
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Affiliation(s)
- Qianqian Yang
- Institute of Biotechnology, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China; Zhejiang Hospital of Traditional Chinese Medicine, Zhejiang Chinese Medical University, 54 Youdian Road, Hangzhou, 310006, China
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Yuan J, Ching CB. Dynamic control of ERG9 expression for improved amorpha-4,11-diene production in Saccharomyces cerevisiae. Microb Cell Fact 2015; 14:38. [PMID: 25889168 PMCID: PMC4374593 DOI: 10.1186/s12934-015-0220-x] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 03/02/2015] [Indexed: 11/10/2022] Open
Abstract
Background To achieve high-level production of non-native isoprenoid products, it requires the metabolic flux to be diverted from the production of sterols to the heterologous metabolic reactions. However, there are limited tools for restricting metabolic flux towards ergosterol synthesis. In the present study, we explored dynamic control of ERG9 expression using different ergosterol-responsive promoters to improve the production of non-native isoprenoids. Results Several ergosterol-responsive promoters were identified using quantitative real-time PCR (qRT-PCR) analysis in an engineered strain with relatively high mevalonate pathway activity. We found mRNA levels for ERG11, ERG2 and ERG3 expression were significantly lower in the engineered strain over the reference strain BY4742, indicating these genes are transcriptionally down-regulated when ergosterol is in excess. Further replacement of the native ERG9 promoter with these ergosterol-responsive promoters revealed that all engineered strains improved amorpha-4,11-diene by 2 ~ 5-fold over the reference strain with ERG9 under its native promoter. The best engineered strain with ERG9 under the control of PERG1 produced amorpha-4,11-diene to a titer around 350 mg/L after 96 h cultivation in shake-flasks. Conclusions We envision dynamic control at the branching step using feedback regulation at transcriptional level could serve as a generalized approach for redirecting the metabolic flux towards product-of-interest.
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Affiliation(s)
- Jifeng Yuan
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore. .,Synthetic Biology Research Consortium, National University of Singapore, 28 Medical Drive, Singapore, 117456, Singapore.
| | - Chi-Bun Ching
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore. .,Synthetic Biology Research Consortium, National University of Singapore, 28 Medical Drive, Singapore, 117456, Singapore. .,Singapore Institute of Technology, 10 Dover Drive, Singapore, 138683, Singapore.
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Yang H, Tong J, Lee CW, Ha S, Eom SH, Im YJ. Structural mechanism of ergosterol regulation by fungal sterol transcription factor Upc2. Nat Commun 2015; 6:6129. [PMID: 25655993 DOI: 10.1038/ncomms7129] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 12/15/2014] [Indexed: 11/09/2022] Open
Abstract
Transcriptional regulation of ergosterol biosynthesis in fungi is crucial for sterol homeostasis and for resistance to azole drugs. In Saccharomyces cerevisiae, the Upc2 transcription factor activates the expression of related genes in response to sterol depletion by poorly understood mechanisms. We have determined the structure of the C-terminal domain (CTD) of Upc2, which displays a novel α-helical fold with a deep hydrophobic pocket. We discovered that the conserved CTD is a ligand-binding domain and senses the ergosterol level in the cell. Ergosterol binding represses its transcription activity, while dissociation of the ligand leads to relocalization of Upc2 from cytosol to nucleus for transcriptional activation. The C-terminal activation loop is essential for ligand binding and for transcriptional regulation. Our findings highlight that Upc2 represents a novel class of fungal zinc cluster transcription factors, which can serve as a target for the developments of antifungal therapeutics.
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Affiliation(s)
- Huiseon Yang
- College of Pharmacy, Chonnam National University, Gwangju 500-757, South Korea
| | - Junsen Tong
- College of Pharmacy, Chonnam National University, Gwangju 500-757, South Korea
| | - Chul Won Lee
- Department of Chemistry, Chonnam National University, Gwangju 500-757, South Korea
| | - Subin Ha
- College of Pharmacy, Chonnam National University, Gwangju 500-757, South Korea
| | - Soo Hyun Eom
- School of Life Science, Steitz Center for Structural Biology, and Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 500-712, South Korea
| | - Young Jun Im
- College of Pharmacy, Chonnam National University, Gwangju 500-757, South Korea
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Trendeleva TA, Aliverdieva DA, Zvyagilskaya RA. Mechanisms of sensing and adaptive responses to low oxygen conditions in mammals and yeasts. BIOCHEMISTRY (MOSCOW) 2014; 79:750-60. [DOI: 10.1134/s0006297914080033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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UPC2A is required for high-level azole antifungal resistance in Candida glabrata. Antimicrob Agents Chemother 2014; 58:4543-54. [PMID: 24867980 DOI: 10.1128/aac.02217-13] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Candida glabrata, the second most common cause of Candida infections, is associated with high rates of mortality and often exhibits resistance to the azole class of antifungal agents. Upc2 and Ecm22 in Saccharomyces cerevisiae and Upc2 in Candida albicans are the transcriptional regulators of ERG11, the gene encoding the target of azoles in the ergosterol biosynthesis pathway. Recently two homologs for these transcription factors, UPC2A and UPC2B, were identified in C. glabrata. One of these, UPC2A, was shown to influence azole susceptibility. We hypothesized that due to the global role for Upc2 in sterol biosynthesis in S. cerevisiae and C. albicans, disruption of UPC2A would enhance the activity of fluconazole in both azole-susceptible dose-dependent (SDD) and -resistant C. glabrata clinical isolates. To test this hypothesis, we constructed mutants with disruptions in UPC2A and UPC2B alone and in combination in a matched pair of clinical azole-SDD and -resistant isolates. Disruption of UPC2A in both the SDD and resistant isolates resulted in increased susceptibility to sterol biosynthesis inhibitors, including a reduction in fluconazole MIC and minimum fungicidal concentration, enhanced azole activity by time-kill analysis, a decrease in ergosterol content, and downregulation of baseline and inducible expression of several sterol biosynthesis genes. Our results indicate that Upc2A is a key regulator of ergosterol biosynthesis and is essential for resistance to sterol biosynthesis inhibitors in C. glabrata. Therefore, the UPC2A pathway may represent a potential cotherapeutic target for enhancing azole activity against this organism.
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50
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Christadore LM, Pham L, Kolaczyk ED, Schaus SE. Improvement of experimental testing and network training conditions with genome-wide microarrays for more accurate predictions of drug gene targets. BMC SYSTEMS BIOLOGY 2014; 8:7. [PMID: 24444313 PMCID: PMC3911882 DOI: 10.1186/1752-0509-8-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 11/21/2013] [Indexed: 11/10/2022]
Abstract
Background Genome-wide microarrays have been useful for predicting chemical-genetic interactions at the gene level. However, interpreting genome-wide microarray results can be overwhelming due to the vast output of gene expression data combined with off-target transcriptional responses many times induced by a drug treatment. This study demonstrates how experimental and computational methods can interact with each other, to arrive at more accurate predictions of drug-induced perturbations. We present a two-stage strategy that links microarray experimental testing and network training conditions to predict gene perturbations for a drug with a known mechanism of action in a well-studied organism. Results S. cerevisiae cells were treated with the antifungal, fluconazole, and expression profiling was conducted under different biological conditions using Affymetrix genome-wide microarrays. Transcripts were filtered with a formal network-based method, sparse simultaneous equation models and Lasso regression (SSEM-Lasso), under different network training conditions. Gene expression results were evaluated using both gene set and single gene target analyses, and the drug’s transcriptional effects were narrowed first by pathway and then by individual genes. Variables included: (i) Testing conditions – exposure time and concentration and (ii) Network training conditions – training compendium modifications. Two analyses of SSEM-Lasso output – gene set and single gene – were conducted to gain a better understanding of how SSEM-Lasso predicts perturbation targets. Conclusions This study demonstrates that genome-wide microarrays can be optimized using a two-stage strategy for a more in-depth understanding of how a cell manifests biological reactions to a drug treatment at the transcription level. Additionally, a more detailed understanding of how the statistical model, SSEM-Lasso, propagates perturbations through a network of gene regulatory interactions is achieved.
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Affiliation(s)
| | | | | | - Scott E Schaus
- Department of Chemistry, Boston University, Boston, MA, USA.
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