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Kesbiç FI, Gültepe N. Carotenoid characterization, fatty acid profiles, and antioxidant activities of haloarchaeal extracts. J Basic Microbiol 2024; 64:e2300330. [PMID: 37847881 DOI: 10.1002/jobm.202300330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 08/30/2023] [Accepted: 09/24/2023] [Indexed: 10/19/2023]
Abstract
Microorganisms that can survive in saline environments, known as halotolerant or halophilic organisms, have a wide range of current and potential uses in biotechnology. In this study, it was aimed to determine the carotenoids of halophilic archaea strains isolated from the brine samples taken from different points of Salt Lake (Turkey) and determine the antioxidant activities of their carotenoids. To identify the halophilic archaea strains, they were cultivated in MAM JCM 168 medium and subjected to antibiotic susceptibility, fatty acid, two-dimensional and three-dimensional imaging by scanning electron microscopy and atomic force microscopy, biochemical and phylogenetic assays. The findings show that five different halophilic archaea strains have been identified as Halorubrum lipolyticum, Halorubrum sodomense, Haloarcula salaria, Halorubrum chaoviator, and Haloarcula japonica with 98% and above similarity ratio. The main fatty acids of all haloarchaeal strains were octadecanoic acid (C18:0) and palmitic acid (C16:0). The major carotenoid of the species was determined as all-trans bacterioruberin, and different carotenoid types such as lycopene, β-carotene, and 2-isopentenyl-3,4-dehydrorodopin were found as well as bacterioruberin isomers. The antioxidant activities of carotenoids extracted from the species were analyzed by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging method and the extracts showed antioxidant activity statistically significantly higher than ascorbic acid and butylated hydroxytoluene as reference products (p < 0.05).
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Affiliation(s)
| | - Nejdet Gültepe
- Department of Fisheries Fundamental Sciences, Fisheries Faculty, Ataturk University, Erzurum, Turkey
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2
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Zhang J, Li T, Hong Z, Ma C, Fang X, Zheng F, Teng W, Zhang C, Si T. Biosynthesis of Hybrid Neutral Lipids with Archaeal and Eukaryotic Characteristics in Engineered Saccharomyces cerevisiae. Angew Chem Int Ed Engl 2023; 62:e202214344. [PMID: 36424352 DOI: 10.1002/anie.202214344] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 11/26/2022]
Abstract
Discovery of the Asgard superphylum of archaea provides new evidence supporting the two-domain model of life: eukaryotes originated from an Asgard-related archaeon that engulfed a bacterial endosymbiont. However, how eukaryotes acquired bacterial-like membrane lipids with a sn-glycerol-3-phosphate (G3P) backbone instead of the archaeal-like sn-glycerol-1-phosphate (G1P) backbone remains unknown. In this study, we reconstituted archaeal lipid production in Saccharomyces cerevisiae by expressing unsaturated archaeol-synthesizing enzymes. Using Golden Gate cloning for pathway assembly, modular gene replacement was performed, revealing the potential biosynthesis of both G1P- and G3P-based unsaturated archaeol by uncultured Asgard archaea. Unexpectedly, hybrid neutral lipids containing both archaeal isoprenoids and eukaryotic fatty acids were observed in recombinant S. cerevisiae. The ability of yeast and archaeal diacylglycerol acyltransferases to synthesize such hybrid lipids was demonstrated.
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Affiliation(s)
- Jianzhi Zhang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 1068 XueYuan Avenue, Xili, NanShan District, Shenzhen, 518055, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
| | - Tuo Li
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 1068 XueYuan Avenue, Xili, NanShan District, Shenzhen, 518055, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
| | - Zhilai Hong
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 1068 XueYuan Avenue, Xili, NanShan District, Shenzhen, 518055, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
| | - Chenfei Ma
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 1068 XueYuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
| | - Xiaoting Fang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 1068 XueYuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
| | - Fengfeng Zheng
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Department of Ocean Science and Engineering, Southern University of Science and Technology, 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
| | - Wenkai Teng
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Department of Ocean Science and Engineering, Southern University of Science and Technology, 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
| | - Chuanlun Zhang
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Department of Ocean Science and Engineering, Southern University of Science and Technology, 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
| | - Tong Si
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 1068 XueYuan Avenue, Xili, NanShan District, Shenzhen, 518055, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), 1088 Xueyuan Avenue, Xili, NanShan District, Shenzhen, 518055, China
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3
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Wang K, Sybers D, Maklad HR, Lemmens L, Lewyllie C, Zhou X, Schult F, Bräsen C, Siebers B, Valegård K, Lindås AC, Peeters E. A TetR-family transcription factor regulates fatty acid metabolism in the archaeal model organism Sulfolobus acidocaldarius. Nat Commun 2019; 10:1542. [PMID: 30948713 PMCID: PMC6449355 DOI: 10.1038/s41467-019-09479-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 03/12/2019] [Indexed: 01/18/2023] Open
Abstract
Fatty acid metabolism and its regulation are known to play important roles in bacteria and eukaryotes. By contrast, although certain archaea appear to metabolize fatty acids, the regulation of the underlying pathways in these organisms remains unclear. Here, we show that a TetR-family transcriptional regulator (FadRSa) is involved in regulation of fatty acid metabolism in the crenarchaeon Sulfolobus acidocaldarius. Functional and structural analyses show that FadRSa binds to DNA at semi-palindromic recognition sites in two distinct stoichiometric binding modes depending on the operator sequence. Genome-wide transcriptomic and chromatin immunoprecipitation analyses demonstrate that the protein binds to only four genomic sites, acting as a repressor of a 30-kb gene cluster comprising 23 open reading frames encoding lipases and β-oxidation enzymes. Fatty acyl-CoA molecules cause dissociation of FadRSa binding by inducing conformational changes in the protein. Our results indicate that, despite its similarity in overall structure to bacterial TetR-family FadR regulators, FadRSa displays a different acyl-CoA binding mode and a distinct regulatory mechanism. Certain archaea appear to metabolize fatty acids, but the regulation of these pathways is unclear. Here, Wang et al. provide genetic, functional and structural evidence supporting that a TetR-family transcriptional regulator is involved in regulation of fatty acid metabolism in Sulfolobus acidocaldarius.
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Affiliation(s)
- Kun Wang
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrhenius v. 20C, SE-10691, Stockholm, Sweden
| | - David Sybers
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050, Brussels, Belgium
| | - Hassan Ramadan Maklad
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050, Brussels, Belgium
| | - Liesbeth Lemmens
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050, Brussels, Belgium
| | - Charlotte Lewyllie
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050, Brussels, Belgium.,Laboratory of Cell Genetics, Department of Biology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050, Brussels, Belgium
| | - Xiaoxiao Zhou
- Molekulare Enzymtechnologie und Biochemie, Biofilm Centre, ZWU, Fakultät für Chemie, Universität Duisburg-Essen, Universitätsstr. 2, 45117, Essen, Germany
| | - Frank Schult
- Molekulare Enzymtechnologie und Biochemie, Biofilm Centre, ZWU, Fakultät für Chemie, Universität Duisburg-Essen, Universitätsstr. 2, 45117, Essen, Germany
| | - Christopher Bräsen
- Molekulare Enzymtechnologie und Biochemie, Biofilm Centre, ZWU, Fakultät für Chemie, Universität Duisburg-Essen, Universitätsstr. 2, 45117, Essen, Germany
| | - Bettina Siebers
- Molekulare Enzymtechnologie und Biochemie, Biofilm Centre, ZWU, Fakultät für Chemie, Universität Duisburg-Essen, Universitätsstr. 2, 45117, Essen, Germany
| | - Karin Valegård
- Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| | - Ann-Christin Lindås
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrhenius v. 20C, SE-10691, Stockholm, Sweden.
| | - Eveline Peeters
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050, Brussels, Belgium.
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Dibrova DV, Galperin MY, Mulkidjanian AY. Phylogenomic reconstruction of archaeal fatty acid metabolism. Environ Microbiol 2014; 16:907-18. [PMID: 24818264 DOI: 10.1111/1462-2920.12359] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
While certain archaea appear to synthesize and/or metabolize fatty acids, the respective pathways still remain obscure. By analysing the genomic distribution of the key lipid-related enzymes, we were able to identify the likely components of the archaeal pathway of fatty acid metabolism, namely, a combination of the enzymes of bacterial-type β-oxidation of fatty acids [acyl-coenzyme A (CoA) dehydrogenase, enoyl-CoA hydratase and 3-hydroxyacyl-CoA dehydrogenase] with paralogs of the archaeal acetyl-CoA C-acetyltransferase, an enzyme of the mevalonate biosynthesis pathway. These three β-oxidation enzymes working in the reverse direction could potentially catalyse biosynthesis of fatty acids, with paralogs of acetyl-CoA C-acetyltransferase performing addition of C2 fragments. The presence in archaea of the genes for energy-transducing membrane enzyme complexes, such as cytochrome bc complex, cytochrome c oxidase and diverse rhodopsins, was found to correlate with the presence of the proposed system of fatty acid biosynthesis. We speculate that because these membrane complexes functionally depend on fatty acid chains, their genes could have been acquired via lateral gene transfer from bacteria only by those archaea that already possessed a system of fatty acid biosynthesis. The proposed pathway of archaeal fatty acid metabolism operates in extreme conditions and therefore might be of interest in the context of biofuel production and other industrial applications.
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The role of microemulsions in lipase-catalyzed hydrolysis reactions. Biotechnol Prog 2014; 30:360-6. [DOI: 10.1002/btpr.1892] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 02/21/2014] [Indexed: 11/07/2022]
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6
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Koga Y. From promiscuity to the lipid divide: on the evolution of distinct membranes in Archaea and Bacteria. J Mol Evol 2014; 78:234-42. [PMID: 24573438 DOI: 10.1007/s00239-014-9613-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 02/13/2014] [Indexed: 10/25/2022]
Abstract
The structural and biosynthetic features of archaeal phospholipids provide clues to the membrane lipid composition in the last universal common ancestor (LUCA) membranes. The evident similarity of the phospholipid biosynthetic pathways in Archaea and Bacteria suggests that one set of these biosynthetic enzymes would have worked on a wide range of lipids composed of enantiomeric glycerophosphate backbones linked with a variety of hydrocarbon chains. This notion was supported by the discovery of a wide range reactivity of enzymes belonging to the CDP-alcohol phosphatidyltransferase family. It is hypothesized that lipid promiscuity is generated from the prebiotic surface metabolism on pyrite proposed by Wächtershäuser. The significance of the phosphate groups on the intermediates of phospholipid biosynthesis and the extra anionic groups of a polar head group suggested the likely involvement of surface metabolism. Anionic groups are essential for surface metabolism. Since the early chemical evolution reactions are presumed to be non-specific, every combination of the available lipid component parts would be expected to be formed. The mixed lipid membranes present in LUCA were segregated and this led to the differentiation of Archaea and Bacteria, as described previously. The proper arrangement of membrane lipids was generated by the physicochemical drive arising from the promiscuity of the primordial membrane lipids.
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Affiliation(s)
- Yosuke Koga
- University of Occupational and Environmental Health, 9-14-20 Hinosato, Munakata, Fukuoka, 811-3425, Japan,
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7
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Phylogenomic investigation of phospholipid synthesis in archaea. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2012; 2012:630910. [PMID: 23304072 PMCID: PMC3533463 DOI: 10.1155/2012/630910] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 09/03/2012] [Indexed: 12/22/2022]
Abstract
Archaea have idiosyncratic cell membranes usually based on phospholipids containing glycerol-1-phosphate linked by ether bonds to isoprenoid lateral chains. Since these phospholipids strongly differ from those of bacteria and eukaryotes, the origin of the archaeal membranes (and by extension, of all cellular membranes) was enigmatic and called for accurate evolutionary studies. In this paper we review some recent phylogenomic studies that have revealed a modified mevalonate pathway for the synthesis of isoprenoid precursors in archaea and suggested that this domain uses an atypical pathway of synthesis of fatty acids devoid of any acyl carrier protein, which is essential for this activity in bacteria and eukaryotes. In addition, we show new or updated phylogenetic analyses of enzymes likely responsible for the isoprenoid chain synthesis from their precursors and the phospholipid synthesis from glycerol phosphate, isoprenoids, and polar head groups. These results support that most of these enzymes can be traced back to the last archaeal common ancestor and, in many cases, even to the last common ancestor of all living organisms.
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8
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Kouyama T, Kanada S, Takeguchi Y, Narusawa A, Murakami M, Ihara K. Crystal Structure of the Light-Driven Chloride Pump Halorhodopsin from Natronomonas pharaonis. J Mol Biol 2010; 396:564-79. [DOI: 10.1016/j.jmb.2009.11.061] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 11/21/2009] [Accepted: 11/24/2009] [Indexed: 10/20/2022]
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10
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Response of membrane protein to the environment: the case of photosynthetic Reaction Centre. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2002. [DOI: 10.1016/s0928-4931(02)00178-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Abstract
Halorhodopsin, a light-driven halide pump, is the second archaeal rhodopsin involved in ion pumping to be studied at high resolution by X-ray crystallography. Like its cousin bacteriorhodopsin, halorhodopsin couples vectorial ion transport to the isomerisation state of a covalently linked retinal. Given the similarity and interconvertability of these two ion pumps, a unified mechanism for ion translocation by archaeal rhodopsins is now emerging.
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Affiliation(s)
- Lars-Oliver Essen
- Department of Chemistry, Philipps University, Hans-Meerwein-Strasse, D-35032 Marburg, Germany.
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12
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Yu SM, McQuade DT, Quinn MA, Hackenberger CP, Krebs MP, Polans AS, Gellman SH. An improved tripod amphiphile for membrane protein solubilization. Protein Sci 2000; 9:2518-27. [PMID: 11206073 PMCID: PMC2144526 DOI: 10.1110/ps.9.12.2518] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Intrinsic membrane proteins represent a large fraction of the proteins produced by living organisms and perform many crucial functions. Structural and functional characterization of membrane proteins generally requires that they be extracted from the native lipid bilayer and solubilized with a small synthetic amphiphile, for example, a detergent. We describe the development of a small molecule with a distinctive amphiphilic architecture, a "tripod amphiphile," that solubilizes both bacteriorhodopsin (BR) and bovine rhodopsin (Rho). The polar portion of this amphiphile contains an amide and an amine-oxide; small variations in this polar segment are found to have profound effects on protein solubilization properties. The optimal tripod amphiphile extracts both BR and Rho from the native membrane environments and maintains each protein in a monomeric native-like form for several weeks after delipidation. Tripod amphiphiles are designed to display greater conformational rigidity than conventional detergents, with the long-range goal of promoting membrane protein crystallization. The results reported here represent an important step toward that ultimate goal.
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Affiliation(s)
- S M Yu
- Department of Chemistry, University of Wisconsin, Madison 53706, USA
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Kolbe M, Besir H, Essen LO, Oesterhelt D. Structure of the light-driven chloride pump halorhodopsin at 1.8 A resolution. Science 2000; 288:1390-6. [PMID: 10827943 DOI: 10.1126/science.288.5470.1390] [Citation(s) in RCA: 405] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Halorhodopsin, an archaeal rhodopsin ubiquitous in Haloarchaea, uses light energy to pump chloride through biological membranes. Halorhodopsin crystals were grown in a cubic lipidic phase, which allowed the x-ray structure determination of this anion pump at 1.8 angstrom resolution. Halorhodopsin assembles to trimers around a central patch consisting of palmitic acid. Next to the protonated Schiff base between Lys(242) and the isomerizable retinal chromophore, a single chloride ion occupies the transport site. Energetic calculations on chloride binding reveal a combination of ion-ion and ion-dipole interactions for stabilizing the anion 18 angstroms below the membrane surface. Ion dragging across the protonated Schiff base explains why chloride and proton translocation modes are mechanistically equivalent in archaeal rhodopsins.
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Affiliation(s)
- M Kolbe
- Department of Membrane Biochemistry, Max-Planck-Institute for Biochemistry, Am Klopferspitz 18a, D-82152 Martinsried bei München, Germany
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Lopez F, Lobasso S, Colella M, Agostiano A, Corcelli A. Light-dependent and Biochemical Properties of Two Different Bands of Bacteriorhodopsin Isolated on Phenyl-Sepharose CL-4B. Photochem Photobiol 1999. [DOI: 10.1111/j.1751-1097.1999.tb03334.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Affiliation(s)
- B J Rawlings
- Department of Chemistry, University of Leicester, UK.
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Colella M, Lobasso S, Babudri F, Corcelli A. Palmitic acid is associated with halorhodopsin as a free fatty acid. Radiolabeling of halorhodopsin with 3H-palmitic acid and chemical analysis of the reaction products of purified halorhodopsin with thiols and NaBH4. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1370:273-9. [PMID: 9545581 DOI: 10.1016/s0005-2736(97)00276-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Halorhodopsin, isolated from Halobacterium salinarium cells incubated with tritiated palmitic acid, co-elutes with labeled palmitate in phenylsepharose CL-4B chromatography. Halorhodopsin-bound 3H-palmitate is not readily displaced by prolonged exposure to a large excess of detergents and by re-chromatography of radiolabeled halorhodopsin on phenylsepharose. On other hand, the association of labeled palmitate with purified halorhodopsin is not resistant to denaturation induced either by isopropanol/hexane or by SDS gel electrophoresis. We have tested the hypothesis that tightly associated palmitate is bound to halorhodopsin through a thioester bond, which is unstable in denaturing conditions. Using GC/MS, we have analysed the reaction products of native halorhodopsin with specific thioester reagents, thiols and NaBH4, which are inactive on free fatty acids. The results of this analytical approach indicate that there is no thioester bond between halorhodopsin and palmitic acid and that palmitic acid is associated with halorhodopsin as a free fatty acid.
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Affiliation(s)
- M Colella
- Dipartimento di Fisiologia Generale Ambientale, Università degli Studi di Bari, Bari, Italy
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