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Je S, Choi BY, Kim E, Kim K, Lee Y, Yamaoka Y. Sterol Biosynthesis Contributes to Brefeldin-A-Induced Endoplasmic Reticulum Stress Resistance in Chlamydomonas reinhardtii. PLANT & CELL PHYSIOLOGY 2024; 65:916-927. [PMID: 37864404 DOI: 10.1093/pcp/pcad131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 10/03/2023] [Accepted: 10/20/2023] [Indexed: 10/22/2023]
Abstract
The endoplasmic reticulum (ER) stress response is an evolutionarily conserved mechanism in most eukaryotes. In this response, sterols in the phospholipid bilayer play a crucial role in controlling membrane fluidity and homeostasis. Despite the significance of both the ER stress response and sterols in maintaining ER homeostasis, their relationship remains poorly explored. Our investigation focused on Chlamydomonas strain CC-4533 and revealed that free sterol biosynthesis increased in response to ER stress, except in mutants of the ER stress sensor Inositol-requiring enzyme 1 (IRE1). Transcript analysis of Chlamydomonas experiencing ER stress unveiled the regulatory role of the IRE1/basic leucine zipper 1 pathway in inducing the expression of ERG5, which encodes C-22 sterol desaturase. Through the isolation of three erg5 mutant alleles, we observed a defect in the synthesis of Chlamydomonas' sterol end products, ergosterol and 7-dehydroporiferasterol. Furthermore, these erg5 mutants also exhibited increased sensitivity to ER stress induced by brefeldin A (BFA, an inhibitor of ER-Golgi trafficking), whereas tunicamycin (an inhibitor of N-glycosylation) and dithiothreitol (an inhibitor of disulfide-bond formation) had no such effect. Intriguingly, the sterol biosynthesis inhibitors fenpropimorph and fenhexamid, which impede steps upstream of the ERG5 enzyme in sterol biosynthesis, rescued BFA hypersensitivity in CC-4533 cells. Collectively, our findings support the conclusion that the accumulation of intermediates in the sterol biosynthetic pathway influences ER stress in a complex manner. This study highlights the significance and complexity of regulating sterol biosynthesis during the ER stress response in microalgae.
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Affiliation(s)
- Sujeong Je
- Division of Biotechnology, The Catholic University of Korea, 43 Jibong-ro, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Bae Young Choi
- Department of Biological Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Republic of Korea
| | - Eunbi Kim
- Division of Biotechnology, The Catholic University of Korea, 43 Jibong-ro, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Kyungyoon Kim
- Research Institute of Basic Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Yuree Lee
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Yasuyo Yamaoka
- Division of Biotechnology, The Catholic University of Korea, 43 Jibong-ro, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
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2
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Bi Y, Guo P, Liu L, Chen L, Zhang W. Elucidation of sterol biosynthesis pathway and its co-regulation with fatty acid biosynthesis in the oleaginous marine protist Schizochytrium sp. Front Bioeng Biotechnol 2023; 11:1188461. [PMID: 37180050 PMCID: PMC10174431 DOI: 10.3389/fbioe.2023.1188461] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 04/13/2023] [Indexed: 05/15/2023] Open
Abstract
Sterols constitute vital structural and regulatory components of eukaryotic cells. In the oleaginous microorganism Schizochytrium sp. S31, the sterol biosynthetic pathway primarily produces cholesterol, stigmasterol, lanosterol, and cycloartenol. However, the sterol biosynthesis pathway and its functional roles in Schizochytrium remain unidentified. Through Schizochytrium genomic data mining and a chemical biology approach, we first in silico elucidated the mevalonate and sterol biosynthesis pathways of Schizochytrium. The results showed that owing to the lack of plastids in Schizochytrium, it is likely to use the mevalonate pathway as the terpenoid backbone pathway to supply isopentenyl diphosphate for the synthesis of sterols, similar to that in fungi and animals. In addition, our analysis revealed a chimeric organization of the Schizochytrium sterol biosynthesis pathway, which possesses features of both algae and animal pathways. Temporal tracking of sterol profiles reveals that sterols play important roles in Schizochytrium growth, carotenoid synthesis, and fatty acid synthesis. Furthermore, the dynamics of fatty acid and transcription levels of genes involved in fatty acid upon chemical inhibitor-induced sterol inhibition reveal possible co-regulation of sterol synthesis and fatty acid synthesis, as the inhibition of sterol synthesis could promote the accumulation of fatty acid in Schizochytrium. Sterol and carotenoid metabolisms are also found possibly co-regulated, as the inhibition of sterols led to decreased carotenoid synthesis through down-regulating the gene HMGR and crtIBY in Schizochytrium. Together, elucidation of the Schizochytrium sterol biosynthesis pathway and its co-regulation with fatty acid synthesis lay the essential foundation for engineering Schizochytrium for the sustainable production of lipids and high-value chemicals.
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Affiliation(s)
- Yali Bi
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
| | - Pengfei Guo
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
| | - Liangsen Liu
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
| | - Lei Chen
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin, China
- *Correspondence: Weiwen Zhang,
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Prihanto AA, Jatmiko YD, Nurdiani R, Miftachurrochmah A, Wakayama M. Freshwater Microalgae as Promising Food Sources: Nutritional and Functional Properties. Open Microbiol J 2022. [DOI: 10.2174/18742858-v16-e2206200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A number of researchers have predicted that the current food crisis is predicted to worsen in 2050. The prediction of this crisis is aligned with climate change causing increases in some basic foodstuff prices. Therefore, everyone should prepare to consume alternative foods at an early stage. Alternative foods have been widely developed, one of which involves microalgae. However, the type of microalgae produced by some countries on a large scale consists of only oceanic/seawater microalgae. This will have an impact on and hinder development in countries that do not have these resources. Therefore, it is necessary to explore the use of microalgae derived from freshwater. Unfortunately, freshwater microalgae are still rarely investigated for use as alternative foods. However, there is considerable potential to utilize freshwater microalgae, and these algae are very abundant and diverse. In terms of nutritional properties, compared to oceanic / seawater microalgae, freshwater microalgae contain nearly the same protein and amino acids, lipids and fatty acids, carbohydrates, and vitamins. There are even more species whose composition is similar to those currently consumed foods, such as beef, chicken, beans, eggs, and corn. In addition to dietary properties, freshwater microalgae also have functional properties, due to the presence of pigments, sterols, fatty acids, and polyphenols. Given the potential of freshwater microalgae, these aquatic resources need to be developed for potential use as future food resources.
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4
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Wang J, Guo Y, Yin X, Wang X, Qi X, Xue Z. Diverse triterpene skeletons are derived from the expansion and divergent evolution of 2,3-oxidosqualene cyclases in plants. Crit Rev Biochem Mol Biol 2021; 57:113-132. [PMID: 34601979 DOI: 10.1080/10409238.2021.1979458] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Triterpenoids are one of the largest groups of secondary metabolites and exhibit diverse structures, which are derived from C30 skeletons that are biosynthesized via the isoprenoid pathway by cyclization of 2,3-oxidosqualene. Triterpenoids have a wide range of biological activities, and are used in functional foods, drugs, and as industrial materials. Due to the low content levels in their native plants and limited feasibility and efficiency of chemical synthesis, heterologous biosynthesis of triterpenoids is the most promising strategy. Herein, we classified 121 triterpene alcohols/ketones according to their conformation and ring numbers, among which 51 skeletons have been experimentally characterized as the products of oxidosqualene cyclases (OSCs). Interestingly, 24 skeletons that have not been reported from nature source were generated by OSCs in heterologous expression. Comprehensive evolutionary analysis of the identified 152 OSCs from 75 species in 25 plant orders show that several pentacyclic triterpene synthases repeatedly originated in multiple plant lineages. Comparative analysis of OSC catalytic reaction revealed that stabilization of intermediate cations, steric hindrance, and conformation of active center amino acid residues are primary factors affecting triterpene formation. Optimization of OSC could be achieved by changing of side-chain orientations of key residues. Recently, methods, such as rationally design of pathways, regulation of metabolic flow, compartmentalization engineering, etc., were introduced in improving chassis for the biosynthesis of triterpenoids. We expect that extensive study of natural variation of large number of OSCs and catalytical mechanism will provide basis for production of high level of triterpenoids by application of synthetic biology strategies.
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Affiliation(s)
- Jing Wang
- Ministry of Education, Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Northeast Forestry University, Harbin, PR China.,Heilongjiang Key Laboratory of Plant Bioactive Substance Biosynthesis and Utilization, Northeast Forestry University, Harbin, PR China.,Institute of Forestry and Pomology, Beijing Academy of Agriculture and Forestry Sciences, Beijing, PR China
| | - Yanhong Guo
- Ministry of Education, Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Northeast Forestry University, Harbin, PR China.,Heilongjiang Key Laboratory of Plant Bioactive Substance Biosynthesis and Utilization, Northeast Forestry University, Harbin, PR China
| | - Xue Yin
- Ministry of Education, Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Northeast Forestry University, Harbin, PR China.,Heilongjiang Key Laboratory of Plant Bioactive Substance Biosynthesis and Utilization, Northeast Forestry University, Harbin, PR China
| | - Xiaoning Wang
- Department of Natural Product Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, PR China
| | - Xiaoquan Qi
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, PR China
| | - Zheyong Xue
- Ministry of Education, Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Northeast Forestry University, Harbin, PR China.,Heilongjiang Key Laboratory of Plant Bioactive Substance Biosynthesis and Utilization, Northeast Forestry University, Harbin, PR China
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5
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Voshall A, Christie NTM, Rose SL, Khasin M, Van Etten JL, Markham JE, Riekhof WR, Nickerson KW. Sterol Biosynthesis in Four Green Algae: A Bioinformatic Analysis of the Ergosterol Versus Phytosterol Decision Point. JOURNAL OF PHYCOLOGY 2021; 57:1199-1211. [PMID: 33713347 PMCID: PMC8453531 DOI: 10.1111/jpy.13164] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 02/02/2021] [Indexed: 06/12/2023]
Abstract
Animals and fungi produce cholesterol and ergosterol, respectively, while plants produce the phytosterols stigmasterol, campesterol, and β-sitosterol in various combinations. The recent sequencing of many algal genomes allows the detailed reconstruction of the sterol metabolic pathways. Here, we characterized sterol synthesis in two sequenced Chlorella spp., the free-living C. sorokiniana, and symbiotic C. variabilis NC64A. Chlamydomonas reinhardtii was included as an internal control and Coccomyxa subellipsoidea as a plant-like outlier. We found that ergosterol was the major sterol produced by Chlorella spp. and C. reinhardtii, while C. subellipsoidea produced the three phytosterols found in plants. In silico analysis of the C. variabilis NC64A, C. sorokiniana, and C. subellipsoidea genomes identified 22 homologs of sterol biosynthetic genes from Arabidopsis thaliana, Saccharomyces cerevisiae, and C. reinhardtii. The presence of CAS1, CPI1, and HYD1 in the four algal genomes suggests the higher plant cycloartenol branch for sterol biosynthesis, confirming that algae and fungi use different pathways for ergosterol synthesis. Phylogenetic analysis for 40 oxidosqualene cyclases (OSCs) showed that the nine algal OSCs clustered with the cycloartenol cyclases, rather than the lanosterol cyclases, with the OSC for C. subellipsoidea positioned in between the higher plants and the eight other algae. With regard to why C. subellipsoidea produced phytosterols instead of ergosterol, we identified 22 differentially conserved positions where C. subellipsoidea CAS and A. thaliana CAS1 have one amino acid while the three ergosterol producing algae have another. Together, these results emphasize the position of the unicellular algae as an evolutionary transition point for sterols.
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Affiliation(s)
- Adam Voshall
- Division of Genetics and GenomicsBoston Children’s Hospital and Harvard Medical SchoolBostonMassachusetts02115USA
| | - Nakeirah T. M. Christie
- Department of Molecular Biophysics & BiochemistryYale UniversityNew Haven, Connecticut06520USA
| | - Suzanne L. Rose
- School of Biological SciencesUniversity of NebraskaLincolnNebraska68588‐0666USA
| | - Maya Khasin
- Wheat, Sorghum, and Forage Research UnitUSDALincolnNebraska68583‐0937USA
| | - James L. Van Etten
- Department of Plant Pathology, and Nebraska Center for VirologyUniversity of NebraskaLincolnNebraska68583‐0900USA
| | - Jennifer E. Markham
- Department of Biochemistry, and Center for Plant Science InnovationUniversity of NebraskaLincolnNebraska68588‐0664USA
| | - Wayne R. Riekhof
- School of Biological SciencesUniversity of NebraskaLincolnNebraska68588‐0666USA
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6
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Johnson JB, Ekanayake CP, Caravani F, Mani JS, Lal P, Calgaro SJ, Prasad SS, Warner RD, Naiker M. A Review of Vitamin D and Its Precursors in Plants and Their Translation to Active Metabolites in Meat. FOOD REVIEWS INTERNATIONAL 2021. [DOI: 10.1080/87559129.2021.1936006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Joel B. Johnson
- School of Health, Medical & Applied Sciences, CQUniversity, North Rockhampton, Australia
| | - C. P. Ekanayake
- Department of Chemistry, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Federico Caravani
- School of Health, Medical & Applied Sciences, CQUniversity, North Rockhampton, Australia
| | - Janice S. Mani
- School of Health, Medical & Applied Sciences, CQUniversity, North Rockhampton, Australia
| | - Pawan Lal
- School of Health, Medical & Applied Sciences, CQUniversity, North Rockhampton, Australia
| | - Sarah J. Calgaro
- School of Health, Medical & Applied Sciences, CQUniversity, North Rockhampton, Australia
| | - Shirtika S. Prasad
- Faculty of Science, Technology and Engineering, the University of the South Pacific, Laucala Campus, Suva, Fiji
| | - Robyn D Warner
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, Australia
| | - Mani Naiker
- School of Health, Medical & Applied Sciences, CQUniversity, North Rockhampton, Australia
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7
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Dembitsky VM, Gloriozova TA, Poroikov VV. Antitumor Profile of Carbon-Bridged Steroids (CBS) and Triterpenoids. Mar Drugs 2021; 19:324. [PMID: 34205074 PMCID: PMC8228860 DOI: 10.3390/md19060324] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/01/2021] [Accepted: 06/01/2021] [Indexed: 12/12/2022] Open
Abstract
This review focuses on the rare group of carbon-bridged steroids (CBS) and triterpenoids found in various natural sources such as green, yellow-green, and red algae, marine sponges, soft corals, ascidians, starfish, and other marine invertebrates. In addition, this group of rare lipids is found in amoebas, fungi, fungal endophytes, and plants. For convenience, the presented CBS and triterpenoids are divided into four groups, which include: (a) CBS and triterpenoids containing a cyclopropane group; (b) CBS and triterpenoids with cyclopropane ring in the side chain; (c) CBS and triterpenoids containing a cyclobutane group; (d) CBS and triterpenoids containing cyclopentane, cyclohexane or cycloheptane moieties. For the comparative characterization of the antitumor profile, we have added several semi- and synthetic CBS and triterpenoids, with various additional rings, to identify possible promising sources for pharmacologists and the pharmaceutical industry. About 300 CBS and triterpenoids are presented in this review, which demonstrate a wide range of biological activities, but the most pronounced antitumor profile. The review summarizes biological activities both determined experimentally and estimated using the well-known PASS software. According to the data obtained, two-thirds of CBS and triterpenoids show moderate activity levels with a confidence level of 70 to 90%; however, one third of these lipids demonstrate strong antitumor activity with a confidence level exceeding 90%. Several CBS and triterpenoids, from different lipid groups, demonstrate selective action on different types of tumor cells such as renal cancer, sarcoma, pancreatic cancer, prostate cancer, lymphocytic leukemia, myeloid leukemia, liver cancer, and genitourinary cancer with varying degrees of confidence. In addition, the review presents graphical images of the antitumor profile of both individual CBS and triterpenoids groups and individual compounds.
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Affiliation(s)
- Valery M. Dembitsky
- Centre for Applied Research, Innovation and Entrepreneurship, Lethbridge College, 3000 College Drive South, Lethbridge, AB T1K 1L6, Canada
| | - Tatyana A. Gloriozova
- Institute of Biomedical Chemistry, Bldg. 8, 10 Pogodinskaya Str., 119121 Moscow, Russia; (T.A.G.); (V.V.P.)
| | - Vladimir V. Poroikov
- Institute of Biomedical Chemistry, Bldg. 8, 10 Pogodinskaya Str., 119121 Moscow, Russia; (T.A.G.); (V.V.P.)
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8
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Darnet S, Blary A, Chevalier Q, Schaller H. Phytosterol Profiles, Genomes and Enzymes - An Overview. FRONTIERS IN PLANT SCIENCE 2021; 12:665206. [PMID: 34093623 PMCID: PMC8172173 DOI: 10.3389/fpls.2021.665206] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 04/20/2021] [Indexed: 05/12/2023]
Abstract
The remarkable diversity of sterol biosynthetic capacities described in living organisms is enriched at a fast pace by a growing number of sequenced genomes. Whereas analytical chemistry has produced a wealth of sterol profiles of species in diverse taxonomic groups including seed and non-seed plants, algae, phytoplanktonic species and other unicellular eukaryotes, functional assays and validation of candidate genes unveils new enzymes and new pathways besides canonical biosynthetic schemes. An overview of the current landscape of sterol pathways in the tree of life is tentatively assembled in a series of sterolotypes that encompass major groups and provides also peculiar features of sterol profiles in bacteria, fungi, plants, and algae.
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Affiliation(s)
| | | | | | - Hubert Schaller
- Plant Isoprenoid Biology Team, Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
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Del Mondo A, Smerilli A, Sané E, Sansone C, Brunet C. Challenging microalgal vitamins for human health. Microb Cell Fact 2020; 19:201. [PMID: 33138823 PMCID: PMC7607653 DOI: 10.1186/s12934-020-01459-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 10/17/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Vitamins' deficiency in humans is an important threat worldwide and requires solutions. In the concept of natural biofactory for bioactive compounds production, microalgae represent one of the most promising targets filling many biotechnological applications, and allowing the development of an eco-sustainable production of natural bioactive metabolites. Vitamins are probably one of the cutting edges of microalgal diversity compounds. MAIN TEXT Microalgae can usefully provide many of the required vitamins in humans, more than terrestrial plants, for instance. Indeed, vitamins D and K, little present in many plants or fruits, are instead available from microalgae. The same occurs for some vitamins B (B12, B9, B6), while the other vitamins (A, C, D, E) are also provided by microalgae. This large panel of vitamins diversity in microalgal cells represents an exploitable platform in order to use them as natural vitamins' producers for human consumption. This study aims to provide an integrative overview on vitamins content in the microalgal realm, and discuss on the great potential of microalgae as sources of different forms of vitamins to be included as functional ingredients in food or nutraceuticals for the human health. We report on the biological roles of vitamins in microalgae, the current knowledge on their modulation by environmental or biological forcing and on the biological activity of the different vitamins in human metabolism and health protection. CONCLUSION Finally, we critically discuss the challenges for promoting microalgae as a relevant source of vitamins, further enhancing the interests of microalgal "biofactory" for biotechnological applications, such as in nutraceuticals or cosmeceuticals.
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Affiliation(s)
- Angelo Del Mondo
- Stazione Zoologica Anton Dohrn, Istituto Nazionale Di Biologia, Ecologia e Biotecnologie marine, Villa Comunale, 80121, Napoli, Italy
| | - Arianna Smerilli
- Stazione Zoologica Anton Dohrn, Istituto Nazionale Di Biologia, Ecologia e Biotecnologie marine, Villa Comunale, 80121, Napoli, Italy
| | - Elisabet Sané
- Stazione Zoologica Anton Dohrn, Istituto Nazionale Di Biologia, Ecologia e Biotecnologie marine, Villa Comunale, 80121, Napoli, Italy
| | - Clementina Sansone
- Stazione Zoologica Anton Dohrn, Istituto Nazionale Di Biologia, Ecologia e Biotecnologie marine, Villa Comunale, 80121, Napoli, Italy.
| | - Christophe Brunet
- Stazione Zoologica Anton Dohrn, Istituto Nazionale Di Biologia, Ecologia e Biotecnologie marine, Villa Comunale, 80121, Napoli, Italy
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10
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Krespach MKC, García-Altares M, Flak M, Hanno Schoeler, Scherlach K, Netzker T, Schmalzl A, Mattern DJ, Schroeckh V, Komor A, Mittag M, Hertweck C, Brakhage AA. Lichen-like association of Chlamydomonas reinhardtii and Aspergillus nidulans protects algal cells from bacteria. THE ISME JOURNAL 2020; 14:2794-2805. [PMID: 32753730 PMCID: PMC7784976 DOI: 10.1038/s41396-020-0731-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 07/15/2020] [Accepted: 07/23/2020] [Indexed: 11/09/2022]
Abstract
Organismal interactions within microbial consortia and their responses to harmful intruders remain largely understudied. An important step toward the goal of understanding functional ecological interactions and their evolutionary selection is the study of increasingly complex microbial interaction systems. Here, we discovered a tripartite biosystem consisting of the fungus Aspergillus nidulans, the unicellular green alga Chlamydomonas reinhardtii, and the algicidal bacterium Streptomyces iranensis. Genetic analyses and MALDI-IMS demonstrate that the bacterium secretes the algicidal compound azalomycin F upon contact with C. reinhardtii. In co-culture, A. nidulans attracts the motile alga C. reinhardtii, which becomes embedded and surrounded by fungal mycelium and is shielded from the algicide. The filamentous fungus Sordaria macrospora was susceptible to azalomycin F and failed to protect C. reinhardtii despite chemotactically attracting the alga. Because S. macrospora was susceptible to azalomycin F, this data imply that for protection the fungus needs to be resistant. Formation of the lichen-like association between C. reinhardtii and A. nidulans increased algal growth. The protection depends on the increased amounts of membrane lipids provided by resistant fungi, thereby generating a protective shelter against the bacterial toxin. Our findings reveal a strategy whereby algae survive lethal environmental algicides through cooperation with fungi.
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Affiliation(s)
- Mario K C Krespach
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
- Institute for Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - María García-Altares
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
- Metabolomics Platform, Department of Electronic Engineering (DEEEA), Universitat Rovira i Virgili, Tarragona, Spain
| | - Michal Flak
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
- Institute for Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Hanno Schoeler
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
- Institute for Microbiology, Friedrich Schiller University Jena, Jena, Germany
- Biologie des Bactéries Intracellulaires, Institut Pasteur, 28 rue du Dr. Roux, 75015, Paris, France
| | - Kirstin Scherlach
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Tina Netzker
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada
| | - Anica Schmalzl
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
- Institute for Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Derek J Mattern
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Volker Schroeckh
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Anna Komor
- Institute for Microbiology, Friedrich Schiller University Jena, Jena, Germany
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Maria Mittag
- Matthias Schleiden Institute of Genetics, Bioinformatics, and Molecular Botany, Friedrich Schiller University Jena, Jena, Germany
| | - Christian Hertweck
- Institute for Microbiology, Friedrich Schiller University Jena, Jena, Germany
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany.
- Institute for Microbiology, Friedrich Schiller University Jena, Jena, Germany.
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11
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The Delta 5,
7‐Sterols
and Astaxanthin in the Marine Microheterotroph
Schizochytrium
sp.
S31. J AM OIL CHEM SOC 2020. [DOI: 10.1002/aocs.12364] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Fabris M, Abbriano RM, Pernice M, Sutherland DL, Commault AS, Hall CC, Labeeuw L, McCauley JI, Kuzhiuparambil U, Ray P, Kahlke T, Ralph PJ. Emerging Technologies in Algal Biotechnology: Toward the Establishment of a Sustainable, Algae-Based Bioeconomy. FRONTIERS IN PLANT SCIENCE 2020; 11:279. [PMID: 32256509 PMCID: PMC7090149 DOI: 10.3389/fpls.2020.00279] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/24/2020] [Indexed: 05/18/2023]
Abstract
Mankind has recognized the value of land plants as renewable sources of food, medicine, and materials for millennia. Throughout human history, agricultural methods were continuously modified and improved to meet the changing needs of civilization. Today, our rapidly growing population requires further innovation to address the practical limitations and serious environmental concerns associated with current industrial and agricultural practices. Microalgae are a diverse group of unicellular photosynthetic organisms that are emerging as next-generation resources with the potential to address urgent industrial and agricultural demands. The extensive biological diversity of algae can be leveraged to produce a wealth of valuable bioproducts, either naturally or via genetic manipulation. Microalgae additionally possess a set of intrinsic advantages, such as low production costs, no requirement for arable land, and the capacity to grow rapidly in both large-scale outdoor systems and scalable, fully contained photobioreactors. Here, we review technical advancements, novel fields of application, and products in the field of algal biotechnology to illustrate how algae could present high-tech, low-cost, and environmentally friendly solutions to many current and future needs of our society. We discuss how emerging technologies such as synthetic biology, high-throughput phenomics, and the application of internet of things (IoT) automation to algal manufacturing technology can advance the understanding of algal biology and, ultimately, drive the establishment of an algal-based bioeconomy.
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Affiliation(s)
- Michele Fabris
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
- CSIRO Synthetic Biology Future Science Platform, Brisbane, QLD, Australia
| | - Raffaela M. Abbriano
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Mathieu Pernice
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Donna L. Sutherland
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Audrey S. Commault
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Christopher C. Hall
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Leen Labeeuw
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Janice I. McCauley
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | | | - Parijat Ray
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Tim Kahlke
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
| | - Peter J. Ralph
- Climate Change Cluster (C3), University of Technology Sydney, Ultimo, NSW, Australia
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Zhou W, Ramos E, Zhu X, Fisher PM, Kidane ME, Vanderloop BH, Thomas CD, Yan J, Singha U, Chaudhuri M, Nagel MT, Nes WD. Steroidal antibiotics are antimetabolites of Acanthamoeba steroidogenesis with phylogenetic implications. J Lipid Res 2019; 60:981-994. [PMID: 30709898 PMCID: PMC6495176 DOI: 10.1194/jlr.m091587] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 01/22/2019] [Indexed: 12/28/2022] Open
Abstract
Pathogenic organisms may be sensitive to inhibitors of sterol biosynthesis, which carry antimetabolite properties, through manipulation of the key enzyme, sterol methyltransferase (SMT). Here, we isolated natural suicide substrates of the ergosterol biosynthesis pathway, cholesta-5,7,22,24-tetraenol (CHT) and ergosta-5,7,22,24(28)-tetraenol (ERGT), and demonstrated their interference in Acanthamoeba castellanii steroidogenesis: CHT and ERGT inhibit trophozoite growth (EC50 of 51 nM) without affecting cultured human cell growth. Washout experiments confirmed that the target for vulnerability was SMT. Chemical, kinetic, and protein-binding studies of inhibitors assayed with 24-AcSMT [catalyzing C28-sterol via Δ24(28)-olefin production] and 28-AcSMT [catalyzing C29-sterol via Δ25(27)-olefin production] revealed interrupted partitioning and irreversible complex formation from the conjugated double bond system in the side chain of either analog, particularly with 28-AcSMT. Replacement of active site Tyr62 with Phe or Leu residues involved in cation-π interactions that model product specificity prevented protein inactivation. The alkylating properties and high selective index of 103 for CHT and ERGT against 28-AcSMT are indicative of a new class of steroidal antibiotic that, as an antimetabolite, can limit sterol expansion across phylogeny and provide a novel scaffold in the design of amoebicidal drugs. Animal studies of these suicide substrates can further explore the potential of their antibiotic properties.
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Affiliation(s)
- Wenxu Zhou
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Emilio Ramos
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Xunlu Zhu
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Paxtyn M Fisher
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Medhanie E Kidane
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Boden H Vanderloop
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Crista D Thomas
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Juqiang Yan
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Ujjal Singha
- Department of Microbiology and Immunology Meharry Medical College, Nashville, TN 37208
| | - Minu Chaudhuri
- Department of Microbiology and Immunology Meharry Medical College, Nashville, TN 37208
| | - Michael T Nagel
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - W David Nes
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409.
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Göring H. Vitamin D in Nature: A Product of Synthesis and/or Degradation of Cell Membrane Components. BIOCHEMISTRY (MOSCOW) 2018; 83:1350-1357. [DOI: 10.1134/s0006297918110056] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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16
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Haubrich BA. Microbial Sterolomics as a Chemical Biology Tool. Molecules 2018; 23:E2768. [PMID: 30366429 PMCID: PMC6278499 DOI: 10.3390/molecules23112768] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 10/23/2018] [Accepted: 10/23/2018] [Indexed: 02/06/2023] Open
Abstract
Metabolomics has become a powerful tool in chemical biology. Profiling the human sterolome has resulted in the discovery of noncanonical sterols, including oxysterols and meiosis-activating sterols. They are important to immune responses and development, and have been reviewed extensively. The triterpenoid metabolite fusidic acid has developed clinical relevance, and many steroidal metabolites from microbial sources possess varying bioactivities. Beyond the prospect of pharmacognostical agents, the profiling of minor metabolites can provide insight into an organism's biosynthesis and phylogeny, as well as inform drug discovery about infectious diseases. This review aims to highlight recent discoveries from detailed sterolomic profiling in microorganisms and their phylogenic and pharmacological implications.
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Affiliation(s)
- Brad A Haubrich
- Department of Chemistry, University of Nevada, Reno, Reno, NV 89557, USA.
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17
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Zhou W, Warrilow AGS, Thomas CD, Ramos E, Parker JE, Price CL, Vanderloop BH, Fisher PM, Loftis MD, Kelly DE, Kelly SL, Nes WD. Functional importance for developmental regulation of sterol biosynthesis in Acanthamoeba castellanii. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:1164-1178. [PMID: 30044954 PMCID: PMC6180906 DOI: 10.1016/j.bbalip.2018.07.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 06/26/2018] [Accepted: 07/20/2018] [Indexed: 02/07/2023]
Abstract
The sterol metabolome of Acanthamoeba castellanii (Ac) yielded 25 sterols. Substrate screening of cloned AcCYP51 revealed obtusifoliol as the natural substrate which converts to ∆8,14-sterol (<95%). The combination of [2H3-methyl]methionine incubation to intact cultures showing C28-ergosterol incorporates 2-2H atoms and C29-7-dehydroporiferasterol incorporates 5 2H-atoms, the natural distribution of sterols, CYP51 and previously published sterol methyltransferase (SMT) data indicate separate ∆24(28)- and ∆25(27)-olefin pathways to C28- and C29-sterol products from the protosterol cycloartenol. In cell-based culture, we observed a marked change in sterol compositions during the growth and encystment phases monitored microscopically and by trypan blue staining; trophozoites possess C28/C29-∆5,7-sterols, viable encysted cells (mature cyst) possess mostly C29-∆5-sterol and non-viable encysted cells possess C28/C29-∆5,7-sterols that turnover variably from stress to 6-methyl aromatic sterols associated with changed membrane fluidity affording lysis. An incompatible fit of steroidal aromatics in membranes was confirmed using the yeast sterol auxotroph GL7. Only viable cysts, including those treated with inhibitor, can excyst into trophozoites. 25-Azacycloartanol or voriconazole that target SMT and CYP51, respectively, are potent enzyme inhibitors in the nanomolar range against the cloned enzymes and amoeba cells. At minimum amoebicidal concentration of inhibitor amoeboid cells rapidly convert to encysted cells unable to excyst. The correlation between stage-specific sterol compositions and the physiological effects of ergosterol biosynthesis inhibitors suggests that amoeba fitness is controlled mainly by developmentally-regulated changes in the phytosterol B-ring; paired interference in the ∆5,7-sterol biosynthesis (to ∆5,7) - metabolism (to ∆5 or 6-methyl aromatic) congruence during cell proliferation and encystment could be a source of therapeutic intervention for Acanthamoeba infections.
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Affiliation(s)
- Wenxu Zhou
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
| | - Andrew G S Warrilow
- Center for Cytochrome P450 Biodiversity, Institute of Life Science, School of Medicine, Swansea University, Swansea, Wales, United Kingdom
| | - Crista D Thomas
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
| | - Emilio Ramos
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
| | - Josie E Parker
- Center for Cytochrome P450 Biodiversity, Institute of Life Science, School of Medicine, Swansea University, Swansea, Wales, United Kingdom
| | - Claire L Price
- Center for Cytochrome P450 Biodiversity, Institute of Life Science, School of Medicine, Swansea University, Swansea, Wales, United Kingdom
| | - Boden H Vanderloop
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
| | - Paxtyn M Fisher
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
| | - Michael D Loftis
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America
| | - Diane E Kelly
- Center for Cytochrome P450 Biodiversity, Institute of Life Science, School of Medicine, Swansea University, Swansea, Wales, United Kingdom
| | - Steven L Kelly
- Center for Cytochrome P450 Biodiversity, Institute of Life Science, School of Medicine, Swansea University, Swansea, Wales, United Kingdom
| | - W David Nes
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, United States of America.
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18
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Coors A, Vollmar P, Sacher F, Kehrer A. Is there synergistic interaction between fungicides inhibiting different enzymes in the ergosterol biosynthesis pathway in toxicity tests with the green alga Raphidocelis subcapitata? ECOTOXICOLOGY (LONDON, ENGLAND) 2018; 27:936-944. [PMID: 29500666 DOI: 10.1007/s10646-018-1917-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/13/2018] [Indexed: 06/08/2023]
Abstract
Products used for plant protection or as biocides often contain more than one active substance together with numerous formulation additives. The environmental risk assessment for such commercial mixtures applies as default the concept of concentration addition. There is remaining regulatory concern, however, that underestimation of risks can occur if components in the mixture interact synergistically, i.e., elicit effects greater than those predicted by concentration addition. While cases of true synergism appear to be rare, the combination of substances targeting different steps in the same biosynthesis pathway was pointed out as one potential case of synergistic interaction although mechanistic explanations are lacking. The present study aimed to verify this hypothesis using the green alga Raphidocelis subcapitata as the regulatory standard test organism for which such synergism had been indicated earlier. Algal growth inhibition tests were conducted with mixtures of ergosterol biosynthesis inhibitors (tebuconazole, fenpropidin, and fenpropimorph). The fungicides were first tested individually to derive reliable data for a mixture toxicity prediction. The here determined toxicity estimates for two of the fungicides were considerably lower than the endpoints in the regulatory dossiers, which had been used for earlier mixture toxicity predictions. Experimentally observed toxicity estimates for the mixtures deviated <2.6-fold from the predicted values. Hence, the hypothesis of synergistic interaction between fungicides targeting different enzymes in the ergosterol biosynthesis was clearly not confirmed for the green alga R. subcapitata. Overall, the present study demonstrates the importance of reliable and correct input data for mixture toxicity predictions in order to avoid erroneous conclusions on non-additive (synergistic) interactions.
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Affiliation(s)
- Anja Coors
- ECT Oekotoxikologie GmbH, Böttgerstraße 2-14, 65439, Flörsheim, Germany.
| | - Pia Vollmar
- ECT Oekotoxikologie GmbH, Böttgerstraße 2-14, 65439, Flörsheim, Germany
| | - Frank Sacher
- TZW: DVGW-Technologiezentrum Wasser, Karlsruher Straße 84, 76139, Karlsruhe, Germany
| | - Anja Kehrer
- Federal Environment Agency, Woerlitzer Platz 1, 06844, Dessau-Roßlau, Germany
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19
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Kidane ME, Vanderloop BH, Zhou W, Thomas CD, Ramos E, Singha U, Chaudhuri M, Nes WD. Sterol methyltransferase a target for anti-amoeba therapy: towards transition state analog and suicide substrate drug design. J Lipid Res 2017; 58:2310-2323. [PMID: 29042405 PMCID: PMC5711494 DOI: 10.1194/jlr.m079418] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 10/17/2017] [Indexed: 01/18/2023] Open
Abstract
Ergosterol biosynthesis pathways essential to pathogenic protozoa growth and absent from the human host offer new chokepoint targets. Here, we present characterization and cell-based interference of Acanthamoeba spp sterol 24-/28-methylases (SMTs) that catalyze the committed step in C28- and C29-sterol synthesis. Intriguingly, our kinetic analyses suggest that 24-SMT prefers plant cycloartenol whereas 28-SMT prefers 24(28)-methylene lophenol in similar fashion to the substrate preferences of land plant SMT1 and SMT2. Transition state analog-24(R,S),25-epiminolanosterol (EL) and suicide substrate 26,27-dehydrolanosterol (DHL) differentially inhibited trophozoite growth with IC50 values of 7 nM and 6 µM, respectively, and EL yielded 20-fold higher activity than reference drug voriconazole. Against either SMT assayed with native substrate, EL exhibited tight binding ∼Ki 9 nM. Alternatively, DHL is methylated at C26 by 24-SMT that thereby, generates intermediates that complex and inactivate the enzyme, whereas DHL is not productively bound to 28-SMT. Steroidal inhibitors had no effect on human epithelial kidney cell growth or cholesterol biosynthesis at minimum amoebicidal concentrations. We hypothesize the selective inhibition of Acanthamoeba by steroidal inhibitors representing distinct chemotypes may be an efficient strategy for the development of promising compounds to combat amoeba diseases.
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Affiliation(s)
- Medhanie E Kidane
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Boden H Vanderloop
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Wenxu Zhou
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Crista D Thomas
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Emilio Ramos
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
| | - Ujjal Singha
- Department of Microbiology and Immunology, Meharry Medical College, Nashville, TN 37208
| | - Minu Chaudhuri
- Department of Microbiology and Immunology, Meharry Medical College, Nashville, TN 37208
| | - W David Nes
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409
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20
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Hoshino Y, Poshibaeva A, Meredith W, Snape C, Poshibaev V, Versteegh GJM, Kuznetsov N, Leider A, van Maldegem L, Neumann M, Naeher S, Moczydłowska M, Brocks JJ, Jarrett AJM, Tang Q, Xiao S, McKirdy D, Das SK, Alvaro JJ, Sansjofre P, Hallmann C. Cryogenian evolution of stigmasteroid biosynthesis. SCIENCE ADVANCES 2017; 3:e1700887. [PMID: 28948220 PMCID: PMC5606710 DOI: 10.1126/sciadv.1700887] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 08/30/2017] [Indexed: 05/22/2023]
Abstract
Sedimentary hydrocarbon remnants of eukaryotic C26-C30 sterols can be used to reconstruct early algal evolution. Enhanced C29 sterol abundances provide algal cell membranes a density advantage in large temperature fluctuations. Here, we combined a literature review with new analyses to generate a comprehensive inventory of unambiguously syngenetic steranes in Neoproterozoic rocks. Our results show that the capacity for C29 24-ethyl-sterol biosynthesis emerged in the Cryogenian, that is, between 720 and 635 million years ago during the Neoproterozoic Snowball Earth glaciations, which were an evolutionary stimulant, not a bottleneck. This biochemical innovation heralded the rise of green algae to global dominance of marine ecosystems and highlights the environmental drivers for the evolution of sterol biosynthesis. The Cryogenian emergence of C29 sterol biosynthesis places a benchmark for verifying older sterane signatures and sets a new framework for our understanding of early algal evolution.
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Affiliation(s)
- Yosuke Hoshino
- Max Planck Institute for Biogeochemistry, Hans-Knoell-Strasse 10, 07745 Jena, Germany
| | - Aleksandra Poshibaeva
- Gubkin Russian State University of Oil and Gas, Leninsky Prospekt 65, Moscow, Russia
| | - William Meredith
- Faculty of Engineering, University of Nottingham, Energy Technologies Building, Triumph Road, Nottingham NG7 2TU, UK
| | - Colin Snape
- Faculty of Engineering, University of Nottingham, Energy Technologies Building, Triumph Road, Nottingham NG7 2TU, UK
| | - Vladimir Poshibaev
- Gubkin Russian State University of Oil and Gas, Leninsky Prospekt 65, Moscow, Russia
| | - Gerard J. M. Versteegh
- MARUM–Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 8, 28359 Bremen, Germany
- Alfred Wegener Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Nikolay Kuznetsov
- Gubkin Russian State University of Oil and Gas, Leninsky Prospekt 65, Moscow, Russia
- Geological Institute, Russian Academy of Sciences, Pygevsky 7, Moscow, Russia
| | - Arne Leider
- Max Planck Institute for Biogeochemistry, Hans-Knoell-Strasse 10, 07745 Jena, Germany
| | - Lennart van Maldegem
- Max Planck Institute for Biogeochemistry, Hans-Knoell-Strasse 10, 07745 Jena, Germany
- MARUM–Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 8, 28359 Bremen, Germany
| | - Mareike Neumann
- Max Planck Institute for Biogeochemistry, Hans-Knoell-Strasse 10, 07745 Jena, Germany
| | - Sebastian Naeher
- Max Planck Institute for Biogeochemistry, Hans-Knoell-Strasse 10, 07745 Jena, Germany
- MARUM–Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 8, 28359 Bremen, Germany
| | | | - Jochen J. Brocks
- Research School of Earth Sciences, Australian National University, Building 142, Mills Road, Canberra, Australian Capital Territory 2601, Australia
| | - Amber J. M. Jarrett
- Research School of Earth Sciences, Australian National University, Building 142, Mills Road, Canberra, Australian Capital Territory 2601, Australia
| | - Qing Tang
- Department of Geosciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Shuhai Xiao
- Department of Geosciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - David McKirdy
- Department of Earth Science, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Supriyo Kumar Das
- Department of Geology, Presidency University, College Street 86/1, Kolkata 700073, India
| | - José Javier Alvaro
- Instituto de Geociencias (Consejo Superior de Investigaciones Científicas–Universidad Complutense de Madrid), Novais 12, 28040 Madrid, Spain
| | - Pierre Sansjofre
- Laboratoire Géosciences Océan, UMR CNRS-6538, Université de Bretagne Occidentale, 29280 Plouzane, France
| | - Christian Hallmann
- Max Planck Institute for Biogeochemistry, Hans-Knoell-Strasse 10, 07745 Jena, Germany
- MARUM–Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 8, 28359 Bremen, Germany
- Corresponding author.
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21
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Poerschmann J, Koschorreck M, Górecki T. Organic matter in sediment layers of an acidic mining lake as assessed by lipid analysis. Part II: Neutral lipids. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 578:219-227. [PMID: 26848013 DOI: 10.1016/j.scitotenv.2016.01.116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 01/19/2016] [Accepted: 01/19/2016] [Indexed: 06/05/2023]
Abstract
Natural neutralization of acidic mining lakes is often limited by organic matter. The knowledge of the sources and degradability of organic matter is crucial for understanding alkalinity generation in these lakes. Sediments collected at different depths (surface sediment layer from 0 to 1 cm and deep sediment layer from 4 to 5cm) from an acidic mining lake were studied in order to characterize sedimentary organic matter based on neutral signature markers. Samples were exhaustively extracted, subjected to pre-chromatographic derivatizations and analyzed by GC/MS. Herein, molecular distributions of diagnostic alkanes/alkenes, terpenes/terpenoids, polycyclic aromatic hydrocarbons, aliphatic alcohols and ketones, sterols, and hopanes/hopanoids were addressed. Characterization of the contribution of natural vs. anthropogenic sources to the sedimentary organic matter in these extreme environments was then possible based on these distributions. With the exception of polycyclic aromatic hydrocarbons, combined concentrations across all marker classes proved higher in the surface sediment layer as compared to those in the deep sediment layer. Alkane and aliphatic alcohol distributions pointed to predominantly allochthonous over autochthonous contribution to sedimentary organic matter. Sterol patterns were dominated by phytosterols of terrestrial plants including stigmasterol and β-sitosterol. Hopanoid markers with the ββ-biohopanoid "biological" configuration were more abundant in the surface sediment layer, which pointed to higher bacterial activity. The pattern of polycyclic aromatic hydrocarbons pointed to prevailing anthropogenic input. Pyrolytic makers were likely to due to atmospheric deposition from a nearby former coal combustion facility. The combined analysis of the array of biomarkers provided new insights into the sources and transformations of organic matter in lake sediments.
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Affiliation(s)
- Juergen Poerschmann
- Helmholtz Center for Environmental Research-UFZ, Department of Environmental Engineering, Permoserstr. 15, 04318 Leipzig, Germany.
| | - Matthias Koschorreck
- Helmholtz Center for Environmental Research-UFZ, Department of Lake Research, Brueckstr. 3a, 39114 Magdeburg, Germany
| | - Tadeusz Górecki
- Department of Chemistry, University of Waterloo, 200 University Ave. W., Waterloo, ON, N2L 3G1, Canada
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22
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Miller MB, Patkar P, Singha UK, Chaudhuri M, David Nes W. 24-Methylenecyclopropane steroidal inhibitors: A Trojan horse in ergosterol biosynthesis that prevents growth of Trypanosoma brucei. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:305-313. [PMID: 27939999 DOI: 10.1016/j.bbalip.2016.12.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 11/23/2016] [Accepted: 12/05/2016] [Indexed: 01/09/2023]
Abstract
A new class of steroidal therapeutics based on phylogenetic-guided design of covalent inhibitors that target parasite-specific enzymes of ergosterol biosynthesis is shown to prevent growth of the protozoan-Trypanosoma brucei, responsible for sleeping sickness. In the presence of approximately 15±5μM 26,27-dehydrolanosterol, T. brucei procyclic or blood stream form growth is inhibited by 50%. This compound is actively converted by the parasite to an acceptable substrate of sterol C24-methyl transferase (SMT) that upon position-specific side chain methylation at C26 inactivates the enzyme. Treated cells show dose-dependent depletion of ergosterol and other 24β-methyl sterols with no accumulation of intermediates in contradistinction to profiles typical of tight binding inhibitor treatments to azoles showing loss of ergosterol accompanied by accumulation of toxic 14-methyl sterols. HEK cells accumulate 26,27-dehydrolanosterol without effect on cholesterol biosynthesis. During exposure of cloned TbSMT to 26,27-dehydrozymosterol, the enzyme is gradually inactivated (kcat/kinact=0.13min-1/0.08min-1; partition ratio of 1.6) while 26,27-dehydrolanosterol binds nonproductively. GC-MS analysis of the turnover product and bound intermediate released as a C26-methylated diol (C3-OH and C24-OH) confirmed substrate recognition and covalent binding to TbSMT. This study has potential implications for design of a novel class of chemotherapeutic leads functioning as mechanism-based inhibitors of ergosterol biosynthesis to treat neglected tropical diseases.
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Affiliation(s)
- Matthew B Miller
- Department of Chemistry and Biochemistry and Center for Chemical Biology, Texas Tech University, Lubbock, TX 79409, USA
| | - Presheet Patkar
- Department of Chemistry and Biochemistry and Center for Chemical Biology, Texas Tech University, Lubbock, TX 79409, USA
| | - Ujjal K Singha
- Department of Microbiology and Immunology, Meharry Medical College, Nashville, TN 37208, USA
| | - Minu Chaudhuri
- Department of Microbiology and Immunology, Meharry Medical College, Nashville, TN 37208, USA
| | - W David Nes
- Department of Chemistry and Biochemistry and Center for Chemical Biology, Texas Tech University, Lubbock, TX 79409, USA.
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Endogenous B-ring oxysterols inhibit the Hedgehog component Smoothened in a manner distinct from cyclopamine or side-chain oxysterols. Proc Natl Acad Sci U S A 2016; 113:1604984113. [PMID: 27162362 DOI: 10.1073/pnas.1604984113] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Cellular lipids are speculated to act as key intermediates in Hedgehog signal transduction, but their precise identity and function remain enigmatic. In an effort to identify such lipids, we pursued a Hedgehog pathway inhibitory activity that is particularly abundant in flagellar lipids of Chlamydomonas reinhardtii, resulting in the purification and identification of ergosterol endoperoxide, a B-ring oxysterol. A mammalian analog of ergosterol, 7-dehydrocholesterol (7-DHC), accumulates in Smith-Lemli-Opitz syndrome, a human genetic disease that phenocopies deficient Hedgehog signaling and is caused by genetic loss of 7-DHC reductase. We found that depleting endogenous 7-DHC with methyl-β-cyclodextrin treatment enhances Hedgehog activation by a pathway agonist. Conversely, exogenous addition of 3β,5α-dihydroxycholest-7-en-6-one, a naturally occurring B-ring oxysterol derived from 7-DHC that also accumulates in Smith-Lemli-Opitz syndrome, blocked Hedgehog signaling by inhibiting activation of the essential transduction component Smoothened, through a mechanism distinct from Smoothened modulation by other lipids.
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Villain J, Minguez L, Halm-Lemeille MP, Durrieu G, Bureau R. Acute toxicities of pharmaceuticals toward green algae. mode of action, biopharmaceutical drug disposition classification system and quantile regression models. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2016; 124:337-343. [PMID: 26590695 DOI: 10.1016/j.ecoenv.2015.11.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 11/04/2015] [Accepted: 11/05/2015] [Indexed: 06/05/2023]
Abstract
The acute toxicities of 36 pharmaceuticals towards green algae were estimated from a set of quantile regression models representing the first global quantitative structure-activity relationships. The selection of these pharmaceuticals was based on their predicted environmental concentrations. An agreement between the estimated values and the observed acute toxicity values was found for several families of pharmaceuticals, in particular, for antidepressants. A recent classification (BDDCS) of drugs based on ADME properties (Absorption, Distribution, Metabolism and Excretion) was clearly correlated with the acute ecotoxicities towards algae. Over-estimation of toxicity from our QSAR models was observed for classes 2, 3 and 4 whereas our model results were in agreement for the class 1 pharmaceuticals. Clarithromycin, a class 3 antibiotic characterized by weak metabolism and high solubility, was the most toxic to algae (molecular stability and presence in surface water).
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Affiliation(s)
- Jonathan Villain
- UNICAEN, CERMN (Centre d'Etudes et de Recherche sur le Médicament de Normandie), UPRES EA 4258-FR CNRS 3038 INC3M, Bd Becquerel, F-14032 Caen, France; Laboratoire de Mathématiques de Bretagne Atlantique, Université de Bretagne Sud et UMR CNRS 6205, Campus de Tohannic, 56017 Vannes, France
| | - Laetitia Minguez
- Normandie Univ., France; UNICAEN, CERMN (Centre d'Etudes et de Recherche sur le Médicament de Normandie), UPRES EA 4258-FR CNRS 3038 INC3M, Bd Becquerel, F-14032 Caen, France
| | - Marie-Pierre Halm-Lemeille
- Normandie Univ., France; UNICAEN, CERMN (Centre d'Etudes et de Recherche sur le Médicament de Normandie), UPRES EA 4258-FR CNRS 3038 INC3M, Bd Becquerel, F-14032 Caen, France
| | - Gilles Durrieu
- Laboratoire de Mathématiques de Bretagne Atlantique, Université de Bretagne Sud et UMR CNRS 6205, Campus de Tohannic, 56017 Vannes, France
| | - Ronan Bureau
- Normandie Univ., France; UNICAEN, CERMN (Centre d'Etudes et de Recherche sur le Médicament de Normandie), UPRES EA 4258-FR CNRS 3038 INC3M, Bd Becquerel, F-14032 Caen, France.
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Taipale SJ, Hiltunen M, Vuorio K, Peltomaa E. Suitability of Phytosterols Alongside Fatty Acids as Chemotaxonomic Biomarkers for Phytoplankton. FRONTIERS IN PLANT SCIENCE 2016; 7:212. [PMID: 26973664 PMCID: PMC4774056 DOI: 10.3389/fpls.2016.00212] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 02/07/2016] [Indexed: 05/12/2023]
Abstract
The composition and abundance of phytoplankton is an important factor defining ecological status of marine and freshwater ecosystems. Chemotaxonomic markers (e.g., pigments and fatty acids) are needed for monitoring changes in a phytoplankton community and to know the nutritional quality of seston for herbivorous zooplankton. Here we investigated the suitability of sterols along with fatty acids as chemotaxonomic markers using multivariate statistics, by analyzing the sterol and fatty acid composition of 10 different phytoplankton classes including altogether 37 strains isolated from freshwater lakes. We were able to detect a total of 47 fatty acids and 29 sterols in our phytoplankton samples, which both differed statistically significantly between phytoplankton classes. Due to the high variation of fatty acid composition among Cyanophyceae, taxonomical differentiation increased when Cyanophyceae were excluded from statistical analysis. Sterol composition was more heterogeneous within class than fatty acids and did not improve separation of phytoplankton classes when used alongside fatty acids. However, we conclude that sterols can provide additional information on the abundance of specific genera within a class which can be generated by using fatty acids. For example, whereas high C16 ω-3 PUFA (polyunsaturated fatty acid) indicates the presence of Chlorophyceae, a simultaneous high amount of ergosterol could specify the presence of Chlamydomonas spp. (Chlorophyceae). Additionally, we found specific 4α-methyl sterols for distinct Dinophyceae genera, suggesting that 4α-methyl sterols can potentially separate freshwater dinoflagellates from each other.
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Affiliation(s)
- Sami J. Taipale
- Lammi Biological Station, University of HelsinkiLammi, Finland
- Department of Environmental and Biological Sciences, University of Eastern FinlandJoensuu, Finland
- *Correspondence: Sami J. Taipale
| | - Minna Hiltunen
- Department of Environmental and Biological Sciences, University of Eastern FinlandJoensuu, Finland
| | - Kristiina Vuorio
- Department of Biological and Environmental Science, University of JyväskyläJyväskylä, Finland
- Finnish Environment Institute (SYKE)Jyväskylä, Finland
| | - Elina Peltomaa
- Lammi Biological Station, University of HelsinkiLammi, Finland
- Department of Environmental Sciences, University of HelsinkiHelsinki, Finland
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Gas-Pascual E, Simonovik B, Schaller H, Bach TJ. Inhibition of Cycloartenol Synthase (CAS) Function in Tobacco BY-2 Cells. Lipids 2015; 50:761-72. [PMID: 26033687 DOI: 10.1007/s11745-015-4036-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 05/15/2015] [Indexed: 01/06/2023]
Abstract
Tobacco BY-2 cell suspensions are our preferred model for studying isoprenoid biosynthesis pathways, due to their easy genetic transformation and the efficient absorption of metabolic precursors, intermediates, and/or inhibitors. Using this model system, we have analyzed the effects of chemical and genetic blockage of cycloartenol synthase (CAS, EC 5.4.99.8), an oxidosqualene cyclase that catalyzes the first committed step in the sterol pathway of plants. BY-2 cells were treated with RO 48-8071, a potent inhibitor of oxidosqualene cyclization. Short-term treatments (24 h) resulted in accumulation of oxidosqualene with no changes in the final sterol products. Interestingly, long-term treatments (6 days) induced down-regulation in gene expression not only of CAS but also of the SMT2 gene coding sterol methyltransferase 2 (EC 2.1.1.41). This explains some of the increase in 24-methyl sterols at the expense of the 24-ethyl sterols stigmasterol and sitosterol. In our alternative strategy, CAS gene expression was partially blocked by using an inducible artificial microRNA. The limited effectiveness of this approach might be explained by some dependence of the machinery for RNAi formation on an operating MVA/sterol pathway. For comparison we checked the effect of RO 48-8071 on a green cell suspension of Arabidopsis and on seedlings, containing a small spectrum of triterpenes besides phytosterols. Triterpenes remained essentially unaffected, but phytosterol accumulation was clearly diminished.
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Affiliation(s)
- Elisabet Gas-Pascual
- Department of Horticulture and Crop Science, The Ohio State University, Wooster, OH, 44691, USA
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Luo X, Su P, Zhang W. Advances in Microalgae-Derived Phytosterols for Functional Food and Pharmaceutical Applications. Mar Drugs 2015; 13:4231-54. [PMID: 26184233 PMCID: PMC4515614 DOI: 10.3390/md13074231] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 06/29/2015] [Accepted: 06/29/2015] [Indexed: 11/30/2022] Open
Abstract
Microalgae contain a variety of bioactive lipids with potential applications in aquaculture feed, biofuel, food and pharmaceutical industries. While microalgae-derived polyunsaturated fatty acid (PUFA) and their roles in promoting human health have been extensively studied, other lipid types from this resource, such as phytosterols, have been poorly explored. Phytosterols have been used as additives in many food products such as spread, dairy products and salad dressing. This review focuses on the recent advances in microalgae-derived phytosterols with functional bioactivities and their potential applications in functional food and pharmaceutical industries. It highlights the importance of microalgae-derived lipids other than PUFA for the development of an advanced microalgae industry.
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Affiliation(s)
- Xuan Luo
- Flinders Centre for Marine Bioproducts Development, Flinders University, Adelaide, SA 5042, Australia.
- Department of Medical Biotechnology, School of Medicine, Flinders University, Adelaide, SA 5042, Australia.
| | - Peng Su
- Flinders Centre for Marine Bioproducts Development, Flinders University, Adelaide, SA 5042, Australia.
- Department of Medical Biotechnology, School of Medicine, Flinders University, Adelaide, SA 5042, Australia.
| | - Wei Zhang
- Flinders Centre for Marine Bioproducts Development, Flinders University, Adelaide, SA 5042, Australia.
- Department of Medical Biotechnology, School of Medicine, Flinders University, Adelaide, SA 5042, Australia.
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Haubrich BA, Collins EK, Howard AL, Wang Q, Snell WJ, Miller MB, Thomas CD, Pleasant SK, Nes WD. Characterization, mutagenesis and mechanistic analysis of an ancient algal sterol C24-methyltransferase: Implications for understanding sterol evolution in the green lineage. PHYTOCHEMISTRY 2015; 113:64-72. [PMID: 25132279 PMCID: PMC5182512 DOI: 10.1016/j.phytochem.2014.07.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Revised: 07/11/2014] [Accepted: 06/09/2014] [Indexed: 05/15/2023]
Abstract
Sterol C24-methyltransferases (SMTs) constitute a group of sequence-related proteins that catalyze the pattern of sterol diversity across eukaryotic kingdoms. The only gene for sterol alkylation in green algae was identified and the corresponding catalyst from Chlamydomonas reinhardtii (Cr) was characterized kinetically and for product distributions. The properties of CrSMT were similar to those predicted for an ancient SMT expected to possess broad C3-anchoring requirements for substrate binding and formation of 24β-methyl/ethyl Δ(25(27))-olefin products typical of primitive organisms. Unnatural Δ(24(25))-sterol substrates, missing a C4β-angular methyl group involved with binding orientation, convert to product ratios in favor of Δ(24(28))-products. Remodeling the active site to alter the electronics of Try110 (to Leu) results in delayed timing of the hydride migration from methyl attack of the Δ(24)-bond, that thereby produces metabolic switching of product ratios in favor of Δ(25(27))-olefins or impairs the second C1-transfer activity. Incubation of [27-(13)C]lanosterol or [methyl-(2)H3]SAM as co-substrates established the CrSMT catalyzes a sterol methylation pathway by the "algal" Δ(25(27))-olefin route, where methylation proceeds by a conserved SN2 reaction and de-protonation proceeds from the pro-Z methyl group on lanosterol corresponding to C27. This previously unrecognized catalytic competence for an enzyme of sterol biosynthesis, together with phylogenomic analyses, suggest that mutational divergence of a promiscuous SMT produced substrate- and phyla-specific SMT1 (catalyzes first biomethylation) and SMT2 (catalyzes second biomethylation) isoforms in red and green algae, respectively, and in the case of SMT2 selection afforded modification in reaction channeling necessary for the switch in ergosterol (24β-methyl) biosynthesis to stigmasterol (24α-ethyl) biosynthesis during the course of land plant evolution.
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Affiliation(s)
- Brad A Haubrich
- Center for Chemical Biology and Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - Emily K Collins
- Center for Chemical Biology and Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - Alicia L Howard
- Center for Chemical Biology and Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - Qian Wang
- Department of Cell Biology, University of Texas Southwestern Medical School, Dallas, TX 75390, United States
| | - William J Snell
- Department of Cell Biology, University of Texas Southwestern Medical School, Dallas, TX 75390, United States
| | - Matthew B Miller
- Center for Chemical Biology and Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - Crista D Thomas
- Center for Chemical Biology and Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - Stephanie K Pleasant
- Center for Chemical Biology and Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, United States
| | - W David Nes
- Center for Chemical Biology and Department of Chemistry & Biochemistry, Texas Tech University, Lubbock, TX 79409, United States.
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Kajikawa M, Kinohira S, Ando A, Shimoyama M, Kato M, Fukuzawa H. Accumulation of squalene in a microalga Chlamydomonas reinhardtii by genetic modification of squalene synthase and squalene epoxidase genes. PLoS One 2015; 10:e0120446. [PMID: 25764133 PMCID: PMC4357444 DOI: 10.1371/journal.pone.0120446] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 01/22/2015] [Indexed: 11/19/2022] Open
Abstract
Several microalgae accumulate high levels of squalene, and as such provide a potentially valuable source of this useful compound. However, the molecular mechanism of squalene biosynthesis in microalgae is still largely unknown. We obtained the sequences of two enzymes involved in squalene synthesis and metabolism, squalene synthase (CrSQS) and squalene epoxidase (CrSQE), from the model green alga Chlamydomonas reinhardtii. CrSQS was functionally characterized by expression in Escherichia coli and CrSQE by complementation of a budding yeast erg1 mutant. Transient expression of CrSQS and CrSQE fused with fluorescent proteins in onion epidermal tissue suggested that both proteins were co-localized in the endoplasmic reticulum. CrSQS-overexpression increased the rate of conversion of 14C-labeled farnesylpyrophosphate into squalene but did not lead to over-accumulation of squalene. Addition of terbinafine caused the accumulation of squalene and suppression of cell survival. On the other hand, in CrSQE-knockdown lines, the expression level of CrSQE was reduced by 59-76% of that in wild-type cells, and significant levels of squalene (0.9-1.1 μg mg-1 cell dry weight) accumulated without any growth inhibition. In co-transformation lines with CrSQS-overexpression and CrSQE-knockdown, the level of squalene was not increased significantly compared with that in solitary CrSQE-knockdown lines. These results indicated that partial knockdown of CrSQE is an effective strategy to increase squalene production in C. reinhardtii cells.
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Affiliation(s)
| | - Seiko Kinohira
- Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Akira Ando
- Graduate School of Humanities and Science, Ochanomizu University, Tokyo, Japan
| | - Miki Shimoyama
- Graduate School of Humanities and Science, Ochanomizu University, Tokyo, Japan
| | - Misako Kato
- Graduate School of Humanities and Science, Ochanomizu University, Tokyo, Japan
| | - Hideya Fukuzawa
- Graduate School of Biostudies, Kyoto University, Kyoto, Japan
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Kim H, Jang S, Kim S, Yamaoka Y, Hong D, Song WY, Nishida I, Li-Beisson Y, Lee Y. The small molecule fenpropimorph rapidly converts chloroplast membrane lipids to triacylglycerols in Chlamydomonas reinhardtii. Front Microbiol 2015; 6:54. [PMID: 25759683 PMCID: PMC4338789 DOI: 10.3389/fmicb.2015.00054] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 01/16/2015] [Indexed: 11/14/2022] Open
Abstract
Concern about global warming has prompted an intense interest in developing economical methods of producing biofuels. Microalgae provide a promising platform for biofuel production, because they accumulate high levels of lipids, and do not compete with food or feed sources. However, current methods of producing algal oil involve subjecting the microalgae to stress conditions, such as nitrogen deprivation, and are prohibitively expensive. Here, we report that the fungicide fenpropimorph rapidly causes high levels of neutral lipids to accumulate in Chlamydomonas reinhardtii cells. When treated with fenpropimorph (10 μg mL(-1)) for 1 h, Chlamydomonas cells accumulated at least fourfold the amount of triacylglycerols (TAGs) present in the untreated control cells. Furthermore, the quantity of TAGs present after 1 h of fenpropimorph treatment was over twofold higher than that formed after 9 days of nitrogen starvation in medium with no acetate supplement. Biochemical analysis of lipids revealed that the accumulated TAGs were derived mainly from chloroplast polar membrane lipids. Such a conversion of chloroplast polar lipids to TAGs is desirable for biodiesel production, because polar lipids are usually removed during the biodiesel production process. Thus, our data exemplified that a cost and time effective method of producing TAGs is possible using fenpropimorph or similar drugs.
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Affiliation(s)
- Hanul Kim
- Division of Molecular and Life Sciences, Pohang University of Science and TechnologyPohang, South Korea
| | - Sunghoon Jang
- Division of Molecular and Life Sciences, Pohang University of Science and TechnologyPohang, South Korea
| | - Sangwoo Kim
- Division of Molecular and Life Sciences, Pohang University of Science and TechnologyPohang, South Korea
| | - Yasuyo Yamaoka
- Division of Molecular and Life Sciences, Pohang University of Science and TechnologyPohang, South Korea
| | - Daewoong Hong
- Division of Molecular and Life Sciences, Pohang University of Science and TechnologyPohang, South Korea
| | - Won-Yong Song
- Division of Molecular and Life Sciences, Pohang University of Science and TechnologyPohang, South Korea
| | - Ikuo Nishida
- Division of Life Science, Graduate School of Science and Engineering, Saitama UniversitySaitama, Japan
| | - Yonghua Li-Beisson
- Department of Plant Biology and Environmental Microbiology, Commissariat à l’Énergie Atomique et aux Énergies Alternatives – Centre National de la Recherche Scientifique – Aix-Marseille UniversitySaint-Paul-Lez-Durance, France
| | - Youngsook Lee
- POSTECH-UZH Global Research Laboratory, Division of Integrative Biology and Biotechnology, Pohang University of Science and TechnologyPohang, South Korea
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Haubrich BA, Singha UK, Miller MB, Nes CR, Anyatonwu H, Lecordier L, Patkar P, Leaver DJ, Villalta F, Vanhollebeke B, Chaudhuri M, Nes WD. Discovery of an ergosterol-signaling factor that regulates Trypanosoma brucei growth. J Lipid Res 2014; 56:331-41. [PMID: 25424002 DOI: 10.1194/jlr.m054643] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ergosterol biosynthesis and homeostasis in the parasitic protozoan Trypanosoma brucei was analyzed by RNAi silencing and inhibition of sterol C24β-methyltransferase (TbSMT) and sterol 14α-demethylase [TbSDM (TbCYP51)] to explore the functions of sterols in T. brucei growth. Inhibition of the amount or activity of these enzymes depletes ergosterol from cells at <6 fg/cell for procyclic form (PCF) cells or <0.01 fg/cell for bloodstream form (BSF) cells and reduces infectivity in a mouse model of infection. Silencing of TbSMT expression by RNAi in PCF or BSF in combination with 25-azalanosterol (AZA) inhibited parasite growth and this inhibition was restored completely by adding synergistic cholesterol (7.8 μM from lipid-depleted media) with small amounts of ergosterol (1.2 μM) to the medium. These observations are consistent with the proposed requirement for ergosterol as a signaling factor to spark cell proliferation while imported cholesterol or the endogenously formed cholesta-5,7,24-trienol act as bulk membrane components. To test the potential chemotherapeutic importance of disrupting ergosterol biosynthesis using pairs of mechanism-based inhibitors that block two enzymes in the post-squalene segment, parasites were treated with AZA and itraconazole at 1 μM each (ED50 values) resulting in parasite death. Taken together, our results demonstrate that the ergosterol pathway is a prime drug target for intervention in T. brucei infection.
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Affiliation(s)
- Brad A Haubrich
- Center for Chemical Biology and Department of Chemistry and Biochemistry Texas Tech University, Lubbock, TX 79409
| | - Ujjal K Singha
- Department of Microbiology and Immunology, Meharry Medical College, Nashville, TN 37208
| | - Matthew B Miller
- Center for Chemical Biology and Department of Chemistry and Biochemistry Texas Tech University, Lubbock, TX 79409
| | - Craigen R Nes
- Center for Chemical Biology and Department of Chemistry and Biochemistry Texas Tech University, Lubbock, TX 79409
| | - Hosanna Anyatonwu
- Center for Chemical Biology and Department of Chemistry and Biochemistry Texas Tech University, Lubbock, TX 79409
| | - Laurence Lecordier
- Laboratoire de Parasitologie Moléculaire, IBMM, Université Libre de Bruxelles, B6041 Gosselies, Belgium
| | - Presheet Patkar
- Center for Chemical Biology and Department of Chemistry and Biochemistry Texas Tech University, Lubbock, TX 79409
| | - David J Leaver
- Center for Chemical Biology and Department of Chemistry and Biochemistry Texas Tech University, Lubbock, TX 79409 Institute of Chemistry and Biomedical Sciences, Nanjing University, Nanjing 210023, People's Republic of China
| | - Fernando Villalta
- Department of Microbiology and Immunology, Meharry Medical College, Nashville, TN 37208
| | - Benoit Vanhollebeke
- Laboratoire de Parasitologie Moléculaire, IBMM, Université Libre de Bruxelles, B6041 Gosselies, Belgium
| | - Minu Chaudhuri
- Department of Microbiology and Immunology, Meharry Medical College, Nashville, TN 37208
| | - W David Nes
- Center for Chemical Biology and Department of Chemistry and Biochemistry Texas Tech University, Lubbock, TX 79409
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Fabris M, Matthijs M, Carbonelle S, Moses T, Pollier J, Dasseville R, Baart GJE, Vyverman W, Goossens A. Tracking the sterol biosynthesis pathway of the diatom Phaeodactylum tricornutum. THE NEW PHYTOLOGIST 2014; 204:521-535. [PMID: 24996048 DOI: 10.1111/nph.12917] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 06/02/2014] [Indexed: 05/03/2023]
Abstract
Diatoms are unicellular photosynthetic microalgae that play a major role in global primary production and aquatic biogeochemical cycling. Endosymbiotic events and recurrent gene transfers uniquely shaped the genome of diatoms, which contains features from several domains of life. The biosynthesis pathways of sterols, essential compounds in all eukaryotic cells, and many of the enzymes involved are evolutionarily conserved in eukaryotes. Although well characterized in most eukaryotes, the pathway leading to sterol biosynthesis in diatoms has remained hitherto unidentified. Through the DiatomCyc database we reconstructed the mevalonate and sterol biosynthetic pathways of the model diatom Phaeodactylum tricornutum in silico. We experimentally verified the predicted pathways using enzyme inhibitor, gene silencing and heterologous gene expression approaches. Our analysis revealed a peculiar, chimeric organization of the diatom sterol biosynthesis pathway, which possesses features of both plant and fungal pathways. Strikingly, it lacks a conventional squalene epoxidase and utilizes an extended oxidosqualene cyclase and a multifunctional isopentenyl diphosphate isomerase/squalene synthase enzyme. The reconstruction of the P. tricornutum sterol pathway underscores the metabolic plasticity of diatoms and offers important insights for the engineering of diatoms for sustainable production of biofuels and high-value chemicals.
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Affiliation(s)
- Michele Fabris
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Gent, Belgium
- Department of Biology, Laboratory of Protistology and Aquatic Ecology, Ghent University, Krijgslaan 281 (S8), B-9000, Gent, Belgium
| | - Michiel Matthijs
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Gent, Belgium
- Department of Biology, Laboratory of Protistology and Aquatic Ecology, Ghent University, Krijgslaan 281 (S8), B-9000, Gent, Belgium
| | - Sophie Carbonelle
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Gent, Belgium
| | - Tessa Moses
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Gent, Belgium
| | - Jacob Pollier
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Gent, Belgium
| | - Renaat Dasseville
- Department of Biology, Laboratory of Protistology and Aquatic Ecology, Ghent University, Krijgslaan 281 (S8), B-9000, Gent, Belgium
| | - Gino J E Baart
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Gent, Belgium
- Department of Biology, Laboratory of Protistology and Aquatic Ecology, Ghent University, Krijgslaan 281 (S8), B-9000, Gent, Belgium
| | - Wim Vyverman
- Department of Biology, Laboratory of Protistology and Aquatic Ecology, Ghent University, Krijgslaan 281 (S8), B-9000, Gent, Belgium
| | - Alain Goossens
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Gent, Belgium
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Abstract
This review covers the literature published in 2012 for marine natural products, with 1035 citations (673 for the period January to December 2012) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1241 for 2012), together with the relevant biological activities, source organisms and country of origin. Biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.
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Affiliation(s)
- John W Blunt
- Department of Chemistry, University of Canterbury, Christchurch, New Zealand.
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Storage temperature and UV-irradiation influence on the ergosterol content in edible mushrooms. Food Chem 2014; 147:252-6. [DOI: 10.1016/j.foodchem.2013.09.144] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 04/12/2013] [Accepted: 09/29/2013] [Indexed: 11/18/2022]
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Lu Y, Zhou W, Wei L, Li J, Jia J, Li F, Smith SM, Xu J. Regulation of the cholesterol biosynthetic pathway and its integration with fatty acid biosynthesis in the oleaginous microalga Nannochloropsis oceanica. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:81. [PMID: 24920959 PMCID: PMC4052811 DOI: 10.1186/1754-6834-7-81] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 05/01/2014] [Indexed: 05/08/2023]
Abstract
BACKGROUND Sterols are vital structural and regulatory components in eukaryotic cells; however, their biosynthetic pathways and functional roles in microalgae remain poorly understood. RESULTS In the oleaginous microalga Nannochloropsis oceanica, the sterol biosynthetic pathway produces phytosterols as minor products and cholesterol as the major product. The evidence together with their deduced biosynthetic pathways suggests that N. oceanica exhibits features of both higher plants and mammals. Temporal tracking of sterol profiles and sterol-biosynthetic transcripts in response to changes in light intensity and nitrogen supply reveal that sterols play roles in cell proliferation, chloroplast differentiation, and photosynthesis. Furthermore, the dynamics of fatty acid (FA) and FA-biosynthetic transcripts upon chemical inhibitor-induced sterol depletion reveal possible co-regulation of sterol production and FA synthesis, in that the squalene epoxidase inhibitor terbinafine reduces sterol content yet significantly elevates free FA production. Thus, a feedback regulation of sterol and FA homeostasis is proposed, with the 1-deoxy-D-xylulose 5-phosphate synthase (DXS, the committed enzyme in isoprenoid and sterol biosynthesis) gene potentially subject to feedback regulation by sterols. CONCLUSION These findings reveal features of sterol function and biosynthesis in microalgae and suggest new genetic engineering or chemical biology approaches for enhanced oil production in microalgae.
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Affiliation(s)
- Yandu Lu
- Single-Cell Center, CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China
| | - Wenxu Zhou
- Australian Research Council, Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Li Wei
- Single-Cell Center, CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China
| | - Jing Li
- Australian Research Council, Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Jing Jia
- Single-Cell Center, CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China
| | - Fei Li
- Single-Cell Center, CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China
| | - Steven M Smith
- Australian Research Council, Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Jian Xu
- Single-Cell Center, CAS Key Laboratory of Biofuels and Shandong Key Laboratory of Energy Genetics, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China
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Patkar P, Haubrich BA, Qi M, Nguyen TTM, Thomas CD, Nes WD. C-24-methylation of 26-fluorocycloartenols by recombinant sterol C-24-methyltransferase from soybean: evidence for channel switching and its phylogenetic implications. Biochem J 2013; 456:253-62. [PMID: 23984880 DOI: 10.1042/bj20121818] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The tightly coupled nature of the electrophilic alkylation reaction sequence catalysed by 24-SMT (sterol C-24-methyltransferase) of land plants and algae can be distinguished by the formation of cationic intermediates that yield phyla-specific product profiles. C-24-methylation of the cycloartenol substrate by the recombinant Glycine max (soybean) 24-SMT proceeds to a single product 24(28)-methylenecycloartanol, whereas the 24-SMT from green algae converts cycloartenol into two products cyclolaudenol [∆(25(27))-olefin] and 24(28)-methylenecycloartanol [(∆24(28))-olefin]. Substrate analogues that differed in the steric-electronic features at either end of the molecule, 26-homocycloartenol or 3β-fluorolanostadiene, were converted by G. max SMT into a single 24(28)-methylene product. Alternatively, incubation of the allylic 26-fluoro cyclosteroid with G. max SMT afforded a bound intermediate that converted in favour of the ∆(25(27))-olefin product via the cyclolaudenol cation formed initially during the C-24-methylation reaction. A portion of the 26-fluorocycloartenol substrate was also intercepted by the enzyme and the corresponding hydrolysis product identified by GC-MS as 26-fluoro-25-hydroxy-24-methylcycloartanol. Finally, the 26-fluorocycloartenols are competitive inhibitors for the methylation of cycloartenol and 26-monofluorocycloartenol generated timedependent inactivation kinetics exhibiting a kinact value of 0.12 min(-1). The ability of soybean 24-SMT to generate a 25-hydroxy alkylated sterol and fluorinated ∆(25(27))-olefins is consistent with our hypothesis that (i) achieving the cyclolaudenyl cation intermediate by electrophilic alkylation of cycloartenol is significant to the overall reaction rate, and (ii) the evolution of variant sterol C-24-methylation patterns is driven by competing reaction channels that have switched in algae from formation of primarily ∆(25(27)) products that convert into ergosterol to, in land plants, formation of ∆(24(28)) products that convert into sitosterol.
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Affiliation(s)
- Presheet Patkar
- *Center for Chemical Biology and Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, U.S.A
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Identification of cilia genes that affect cell-cycle progression using whole-genome transcriptome analysis in Chlamydomonas reinhardtti. G3-GENES GENOMES GENETICS 2013; 3:979-91. [PMID: 23604077 PMCID: PMC3689809 DOI: 10.1534/g3.113.006338] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Cilia are microtubule based organelles that project from cells. Cilia are found on almost every cell type of the human body and numerous diseases, collectively termed ciliopathies, are associated with defects in cilia, including respiratory infections, male infertility, situs inversus, polycystic kidney disease, retinal degeneration, and Bardet-Biedl Syndrome. Here we show that Illumina-based whole-genome transcriptome analysis in the biflagellate green alga Chlamydomonas reinhardtii identifies 1850 genes up-regulated during ciliogenesis, 4392 genes down-regulated, and 4548 genes with no change in expression during ciliogenesis. We examined four genes up-regulated and not previously known to be involved with cilia (ZMYND10, NXN, GLOD4, SPATA4) by knockdown of the human orthologs in human retinal pigment epithelial cells (hTERT-RPE1) cells to ask whether they are involved in cilia-related processes that include cilia assembly, cilia length control, basal body/centriole numbers, and the distance between basal bodies/centrioles. All of the genes have cilia-related phenotypes and, surprisingly, our data show that knockdown of GLOD4 and SPATA4 also affects the cell cycle. These results demonstrate that whole-genome transcriptome analysis during ciliogenesis is a powerful tool to gain insight into the molecular mechanism by which centrosomes and cilia are assembled.
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