1
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Matarredona L, García-Bonete MJ, Guío J, Camacho M, Fillat MF, Esclapez J, Bonete MJ. Global Lrp regulator protein from Haloferax mediterranei: Transcriptional analysis and structural characterization. Int J Biol Macromol 2024; 260:129541. [PMID: 38244746 DOI: 10.1016/j.ijbiomac.2024.129541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/03/2024] [Accepted: 01/14/2024] [Indexed: 01/22/2024]
Abstract
Haloferax mediterranei, an extreme halophilic archaeon thriving in hypersaline environments, has acquired significant attention in biotechnological and biochemical research due to its remarkable ability to flourish in extreme salinity conditions. Transcription factors, essential in regulating diverse cellular processes, have become focal points in understanding its adaptability. This study delves into the role of the Lrp transcription factor, exploring its modulation of glnA, nasABC, and lrp gene promoters in vivo through β-galactosidase assays. Remarkably, our findings propose Lrp as the pioneering transcriptional regulator of nitrogen metabolism identified in a haloarchaeon. This study suggests its potential role in activating or repressing assimilatory pathway enzymes (GlnA and NasA). The interaction between Lrp and these promoters is analyzed using Electrophoretic Mobility Shift Assay and Differential Scanning Fluorimetry, highlighting l-glutamine's indispensable role in stabilizing the Lrp-DNA complex. Our research uncovers that halophilic Lrp forms octameric structures in the presence of l-glutamine. The study reveals the three-dimensional structure of the Lrp as a homodimer using X-ray crystallography, confirming this state in solution by Small-Angle X-ray Scattering. These findings illuminate the complex molecular mechanisms driving Hfx. mediterranei's nitrogen metabolism, offering valuable insights about its gene expression regulation and enriching our comprehension of extremophile biology.
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Affiliation(s)
- Laura Matarredona
- Departamento de Bioquímica y Biología Molecular y Edafología y Química Agrícola, Grupo Biotecnología de Extremófilos, Universidad de Alicante, San Vicente del Raspeig, Alicante, Spain
| | - María-José García-Bonete
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine. University of Gothenburg, Sweden
| | - Jorge Guío
- Departamento de Bioquímica y Biología Molecular y Celular, Institute for Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, Zaragoza, Spain
| | - Mónica Camacho
- Departamento de Bioquímica y Biología Molecular y Edafología y Química Agrícola, Grupo Biotecnología de Extremófilos, Universidad de Alicante, San Vicente del Raspeig, Alicante, Spain
| | - María F Fillat
- Departamento de Bioquímica y Biología Molecular y Celular, Institute for Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, Zaragoza, Spain
| | - Julia Esclapez
- Departamento de Bioquímica y Biología Molecular y Edafología y Química Agrícola, Grupo Biotecnología de Extremófilos, Universidad de Alicante, San Vicente del Raspeig, Alicante, Spain.
| | - María-José Bonete
- Departamento de Bioquímica y Biología Molecular y Edafología y Química Agrícola, Grupo Biotecnología de Extremófilos, Universidad de Alicante, San Vicente del Raspeig, Alicante, Spain.
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2
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Yao H, Liu S, Liu T, Ren D, Zhou Z, Yang Q, Mao J. Microbial-derived salt-tolerant proteases and their applications in high-salt traditional soybean fermented foods: a review. BIORESOUR BIOPROCESS 2023; 10:82. [PMID: 38647906 PMCID: PMC10992980 DOI: 10.1186/s40643-023-00704-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 10/31/2023] [Indexed: 04/25/2024] Open
Abstract
Different microorganisms can produce different proteases, which can adapt to different industrial requirements such as pH, temperature, and pressure. Salt-tolerant proteases (STPs) from microorganisms exhibit higher salt tolerance, wider adaptability, and more efficient catalytic ability under extreme conditions compared to conventional proteases. These unique enzymes hold great promise for applications in various industries including food, medicine, environmental protection, agriculture, detergents, dyes, and others. Scientific studies on microbial-derived STPs have been widely reported, but there has been little systematic review of microbial-derived STPs and their application in high-salt conventional soybean fermentable foods. This review presents the STP-producing microbial species and their selection methods, and summarizes and analyzes the salt tolerance mechanisms of the microorganisms. It also outlines various techniques for the isolation and purification of STPs from microorganisms and discusses the salt tolerance mechanisms of STPs. Furthermore, this review demonstrates the contribution of modern biotechnology in the screening of novel microbial-derived STPs and their improvement in salt tolerance. It highlights the potential applications and commercial value of salt-tolerant microorganisms and STPs in high-salt traditional soy fermented foods. The review ends with concluding remarks on the challenges and future directions for microbial-derived STPs. This review provides valuable insights into the separation, purification, performance enhancement, and application of microbial-derived STPs in traditional fermented foods.
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Affiliation(s)
- Hongli Yao
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Department of Biology and Food Engineering, Bozhou University, Bozhou, 236800, Anhui, China
| | - Shuangping Liu
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, Guangdong, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, 31200, Zhejiang, China
- National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing, 646000, Zhejiang, China
| | - Tiantian Liu
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, 31200, Zhejiang, China
- National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing, 646000, Zhejiang, China
| | - Dongliang Ren
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Zhilei Zhou
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, Guangdong, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, 31200, Zhejiang, China
- National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing, 646000, Zhejiang, China
| | - Qilin Yang
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Jian Mao
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, Guangdong, China.
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
- Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, 31200, Zhejiang, China.
- National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing, 646000, Zhejiang, China.
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3
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Blanquart S, Groussin M, Le Roy A, Szöllosi GJ, Girard E, Franzetti B, Gouy M, Madern D. Resurrection of Ancestral Malate Dehydrogenases Reveals the Evolutionary History of Halobacterial Proteins : Deciphering Gene Trajectories and Changes in Biochemical Properties. Mol Biol Evol 2021; 38:3754-3774. [PMID: 33974066 PMCID: PMC8382911 DOI: 10.1093/molbev/msab146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Extreme halophilic Archaea thrive in high salt, where, through proteomic adaptation, they cope with the strong osmolarity and extreme ionic conditions of their environment. In spite of wide fundamental interest, however, studies providing insights into this adaptation are scarce, because of practical difficulties inherent to the purification and characterization of halophilic enzymes. In this work, we describe the evolutionary history of malate dehydrogenases (MalDH) within Halobacteria (a class of the Euryarchaeota phylum). We resurrected nine ancestors along the inferred halobacterial MalDH phylogeny, including the Last Common Ancestral MalDH of Halobacteria (LCAHa) and compared their biochemical properties with those of five modern halobacterial MalDHs. We monitored the stability of these various MalDHs, their oligomeric states and enzymatic properties, as a function of concentration for different salts in the solvent. We found that a variety of evolutionary processes such as amino acid replacement, gene duplication, loss of MalDH gene and replacement owing to horizontal transfer resulted in significant differences in solubility, stability and catalytic properties between these enzymes in the three Halobacteriales, Haloferacales and Natrialbales orders since the LCAHa MalDH.We also showed how a stability trade-off might favor the emergence of new properties during adaptation to diverse environmental conditions. Altogether, our results suggest a new view of halophilic protein adaptation in Archaea.
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Affiliation(s)
| | - Mathieu Groussin
- Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, Villeurbanne, F-69622, France.,Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, USA
| | - Aline Le Roy
- Univ Grenoble Alpes, CNRS, CEA, IBS, Grenoble, F-38000, France
| | - Gergely J Szöllosi
- Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, Villeurbanne, F-69622, France.,MTA-ELTE "Lendulet" Evolutionary Genomics Research Group, Budapest, H-1117, Hungary
| | - Eric Girard
- Univ Grenoble Alpes, CNRS, CEA, IBS, Grenoble, F-38000, France
| | - Bruno Franzetti
- Univ Grenoble Alpes, CNRS, CEA, IBS, Grenoble, F-38000, France
| | - Manolo Gouy
- Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, 43 bd du 11 novembre 1918, Villeurbanne, F-69622, France
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4
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Rani A, Saini KC, Bast F, Mehariya S, Bhatia SK, Lavecchia R, Zuorro A. Microorganisms: A Potential Source of Bioactive Molecules for Antioxidant Applications. Molecules 2021; 26:molecules26041142. [PMID: 33672774 PMCID: PMC7924645 DOI: 10.3390/molecules26041142] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/08/2021] [Accepted: 02/16/2021] [Indexed: 12/17/2022] Open
Abstract
Oxidative stress originates from an elevated intracellular level of free oxygen radicals that cause lipid peroxidation, protein denaturation, DNA hydroxylation, and apoptosis, ultimately impairing cell viability. Antioxidants scavenge free radicals and reduce oxidative stress, which further helps to prevent cellular damage. Medicinal plants, fruits, and spices are the primary sources of antioxidants from time immemorial. In contrast to plants, microorganisms can be used as a source of antioxidants with the advantage of fast growth under controlled conditions. Further, microbe-based antioxidants are nontoxic, noncarcinogenic, and biodegradable as compared to synthetic antioxidants. The present review aims to summarize the current state of the research on the antioxidant activity of microorganisms including actinomycetes, bacteria, fungi, protozoa, microalgae, and yeast, which produce a variety of antioxidant compounds, i.e., carotenoids, polyphenols, vitamins, and sterol, etc. Special emphasis is given to the mechanisms and signaling pathways followed by antioxidants to scavenge Reactive Oxygen Species (ROS), especially for those antioxidant compounds that have been scarcely investigated so far.
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Affiliation(s)
- Alka Rani
- Department of Botany, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, Punjab 151401, India; (A.R.); (K.C.S.); (F.B.)
| | - Khem Chand Saini
- Department of Botany, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, Punjab 151401, India; (A.R.); (K.C.S.); (F.B.)
| | - Felix Bast
- Department of Botany, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, Punjab 151401, India; (A.R.); (K.C.S.); (F.B.)
| | - Sanjeet Mehariya
- Department of Chemical Engineering, Materials and Environment, Sapienza University of Rome, 00184 Rome, Italy;
- Correspondence: (S.M.); (A.Z.); Tel.: +39-347-494-0910 (S.M.); +39-06-4458-5598 (A.Z.)
| | - Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Korea;
| | - Roberto Lavecchia
- Department of Chemical Engineering, Materials and Environment, Sapienza University of Rome, 00184 Rome, Italy;
| | - Antonio Zuorro
- Department of Chemical Engineering, Materials and Environment, Sapienza University of Rome, 00184 Rome, Italy;
- Correspondence: (S.M.); (A.Z.); Tel.: +39-347-494-0910 (S.M.); +39-06-4458-5598 (A.Z.)
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5
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Wang P, Wang Y, Guo X, Huang S, Zhu G. Biochemical and phylogenetic characterization of a monomeric isocitrate dehydrogenase from a marine methanogenic archaeon Methanococcoides methylutens. Extremophiles 2020; 24:319-328. [PMID: 31970482 DOI: 10.1007/s00792-020-01156-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 01/06/2020] [Indexed: 12/13/2022]
Abstract
Monomeric isocitrate dehydrogenase (IDH) stands for a separated subgroup among IDH protein family. Up to now, all reported monomeric IDHs are from prokaryotes. Here, a monomeric IDH from a marine methanogenic archaeon Methanococcoides methylutens (MmIDH) was reported for the first time. BLAST search demonstrated that only a few marine archaea encode the monomeric IDH and all these organisms are methylotrophic. MmIDH shows the highest homology (~ 70%) to the monomeric IDHs from some marine bacteria, suggesting a lateral gene transfer event between marine bacteria and archaea. The monomeric state of MmIDH was determined by size exclusion chromatography. MmIDH is divalent cation-dependent and Mn2+ is the most favored. Kinetic analysis showed that MmIDH is highly specific to NADP+ and cannot utilize the NAD+. The optimal temperature for MmIDH activity is 50 °C and the optimal pH is 8.2. Heat inactivation assay revealed that MmIDH is a mesophilic enzyme. It sustained 50% activity after incubation at 39 °C for 20 min. Moreover, the putative coenzyme binding residues (His590, Arg601, and Arg650) of MmIDH were explored by mutagenesis. The triple mutant H590L/R601D/R650S displayed a 5.93-fold preference for NAD+ over NADP+, indicating that the coenzyme specificity of MmIDH was significantly switched from NADP+ to NAD+ by three key mutations.
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Affiliation(s)
- Peng Wang
- The Research Center of Life Omics and Health and Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, Anhui Normal University, Wuhu, 241000, Anhui, China
| | - Yuan Wang
- The Research Center of Life Omics and Health and Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, Anhui Normal University, Wuhu, 241000, Anhui, China
| | - Xiuxiu Guo
- The Research Center of Life Omics and Health and Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, Anhui Normal University, Wuhu, 241000, Anhui, China
| | - Shiping Huang
- The Research Center of Life Omics and Health and Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, Anhui Normal University, Wuhu, 241000, Anhui, China
| | - Guoping Zhu
- The Research Center of Life Omics and Health and Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources, Anhui Normal University, Wuhu, 241000, Anhui, China.
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6
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Giani M, Garbayo I, Vílchez C, Martínez-Espinosa RM. Haloarchaeal Carotenoids: Healthy Novel Compounds from Extreme Environments. Mar Drugs 2019; 17:md17090524. [PMID: 31500208 PMCID: PMC6780574 DOI: 10.3390/md17090524] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/02/2019] [Accepted: 09/02/2019] [Indexed: 01/08/2023] Open
Abstract
Haloarchaea are halophilic microorganisms belonging to the archaea domain that inhabit salty environments (mainly soils and water) all over the world. Most of the genera included in this group can produce carotenoids at significant concentrations (even wild-type strains). The major carotenoid produced by the cells is bacterioruberin (and its derivatives), which is only produced by this kind of microbes and few bacteria, like Micrococcus roseus. Nevertheless, the understanding of carotenoid metabolism in haloarchaea, its regulation, and the roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. Besides, potential biotechnological uses of haloarchaeal pigments are poorly explored. This work summarises what it has been described so far about carotenoids from haloarchaea and their production at mid- and large-scale, paying special attention to the most recent findings on the potential uses of haloarchaeal pigments in biomedicine.
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Affiliation(s)
- Micaela Giani
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| | - Inés Garbayo
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - Carlos Vílchez
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - Rosa María Martínez-Espinosa
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
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7
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Mokashe N, Chaudhari B, Patil U. Operative utility of salt-stable proteases of halophilic and halotolerant bacteria in the biotechnology sector. Int J Biol Macromol 2018; 117:493-522. [DOI: 10.1016/j.ijbiomac.2018.05.217] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/27/2018] [Accepted: 05/28/2018] [Indexed: 09/30/2022]
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8
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Molecular Cloning and Characterization of a Novel α-Amylase from Antarctic Sea Ice Bacterium Pseudoalteromonas sp. M175 and Its Primary Application in Detergent. BIOMED RESEARCH INTERNATIONAL 2018; 2018:3258383. [PMID: 30050926 PMCID: PMC6040283 DOI: 10.1155/2018/3258383] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 04/06/2018] [Accepted: 05/02/2018] [Indexed: 11/17/2022]
Abstract
A novel cold-adapted and salt-tolerant α-amylase gene (amy175) from Antarctic sea ice bacterium Pseudoalteromonas sp. M175 was successfully cloned and expressed. The open reading frame (ORF) of amy175 had 1722 bp encoding a protein of 573 amino acids residues. Multiple alignments indicated Amy175 had seven highly conserved sequences and the putative catalytic triad (Asp244, Glu286, and Asp372). It was the first identified member of GH13_36 subfamily which contained QPDLN in the CSR V. The recombinant enzyme (Amy175) was purified to homogeneity with a molecular mass of about 62 kDa on SDS-PAGE. It had a mixed enzyme specificity of α-amylase and α-glucosidase. Amy175 displayed highest activity at pH 8.0 and 25°C and exhibited extreme salt-resistance with the maximum activity at 1 M NaCl. Amy175 was strongly stimulated by Mg2+, Ni2+, K+, 1 mM Ca2+, 1 mM Ba2+, 1 mM Pb2+, 1 mM sodium dodecyl sulphate (SDS), and 10% dimethyl sulfoxide (DMSO) but was significantly inhibited by Cu2+, Mn2+, Hg2+, 10 mM β-mercaptoethanol (β-ME), and 10% Tween 80. Amy175 demonstrated excellent resistance towards all the tested commercial detergents, and wash performance analysis displayed that the addition of Amy175 improved the stain removal efficiency. This study demonstrated that Amy175 would be proposed as a novel α-amylase source for industrial application in the future.
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9
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Takahashi M, Takahashi E, Joudeh LI, Marini M, Das G, Elshenawy MM, Akal A, Sakashita K, Alam I, Tehseen M, Sobhy MA, Stingl U, Merzaban JS, Di Fabrizio E, Hamdan SM. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea. FASEB J 2018; 32:3346-3360. [PMID: 29401622 PMCID: PMC6051491 DOI: 10.1096/fj.201700862rr] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The deep-sea brines of the Red Sea are remote and unexplored environments characterized by high temperatures, anoxic water, and elevated concentrations of salt and heavy metals. This environment provides a rare system to study the interplay between halophilic and thermophilic adaptation in biologic macromolecules. The present article reports the first DNA polymerase with halophilic and thermophilic features. Biochemical and structural analysis by Raman and circular dichroism spectroscopy showed that the charge distribution on the protein’s surface mediates the structural balance between stability for thermal adaptation and flexibility for counteracting the salt-induced rigid and nonfunctional hydrophobic packing. Salt bridge interactions via increased negative and positive charges contribute to structural stability. Salt tolerance, conversely, is mediated by a dynamic structure that becomes more fixed and functional with increasing salt concentration. We propose that repulsive forces among excess negative charges, in addition to a high percentage of negatively charged random coils, mediate this structural dynamism. This knowledge enabled us to engineer a halophilic version of Thermococcus kodakarensis DNA polymerase.—Takahashi, M., Takahashi, E., Joudeh, L. I., Marini, M., Das, G., Elshenawy, M. M., Akal, A., Sakashita, K., Alam, I., Tehseen, M., Sobhy, M. A., Stingl, U., Merzaban, J. S., Di Fabrizio, E., Hamdan, S. M. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.
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Affiliation(s)
- Masateru Takahashi
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Etsuko Takahashi
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Luay I Joudeh
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Monica Marini
- Physical Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Gobind Das
- Physical Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Mohamed M Elshenawy
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Anastassja Akal
- Physical Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia.,KAUST Catalysis Center, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Kosuke Sakashita
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Intikhab Alam
- Computational Bioscience Research Center, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia; and
| | - Muhammad Tehseen
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Mohamed A Sobhy
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Ulrich Stingl
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia.,Fort Lauderdale Research and Education Center, University of Florida, Davie, Florida, USA
| | - Jasmeen S Merzaban
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Enzo Di Fabrizio
- Physical Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
| | - Samir M Hamdan
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Jeddah, Saudi Arabia
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10
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Structural adaptations of octaheme nitrite reductases from haloalkaliphilic Thioalkalivibrio bacteria to alkaline pH and high salinity. PLoS One 2017; 12:e0177392. [PMID: 28510595 PMCID: PMC5433712 DOI: 10.1371/journal.pone.0177392] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 04/26/2017] [Indexed: 11/25/2022] Open
Abstract
Bacteria Tv. nitratireducens and Tv. paradoxus from soda lakes grow optimally in sodium carbonate/NaCl brines at pH range from 9.5 to 10 and salinity from 0.5 to 1.5 M Na+. Octaheme nitrite reductases (ONRs) from haloalkaliphilic bacteria of genus Thioalkalivibrio are stable and active in a wide range of pH (up to 11) and salinity (up to 1 M NaCl). To establish adaptation mechanisms of ONRs from haloalkaliphilic bacteria a comparative analysis of amino acid sequences and structures of ONRs from haloalkaliphilic bacteria and their homologues from non-halophilic neutrophilic bacteria was performed. The following adaptation strategies were observed: (1) strategies specific for halophilic and alkaliphilic proteins (an increase in the number of aspartate and glutamate residues and a decrease in the number of lysine residues on the protein surface), (2) strategies specific for halophilic proteins (an increase in the arginine content and a decrease in the number of hydrophobic residues on the solvent-accessible protein surface), (3) strategies specific for alkaliphilic proteins (an increase in the area of intersubunit hydrophobic contacts). Unique adaptation mechanism inherent in the ONRs from bacteria of genus Thioalkalivibrio was revealed (an increase in the core in the number of tryptophan and phenylalanine residues, and an increase in the number of small side chain residues, such as alanine and valine, in the core).
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11
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Rodrigo-Baños M, Garbayo I, Vílchez C, Bonete MJ, Martínez-Espinosa RM. Carotenoids from Haloarchaea and Their Potential in Biotechnology. Mar Drugs 2015; 13:5508-32. [PMID: 26308012 PMCID: PMC4584337 DOI: 10.3390/md13095508] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/02/2015] [Accepted: 08/10/2015] [Indexed: 12/02/2022] Open
Abstract
The production of pigments by halophilic archaea has been analysed during the last half a century. The main reasons that sustains this research are: (i) many haloarchaeal species possess high carotenoids production availability; (ii) downstream processes related to carotenoid isolation from haloarchaea is relatively quick, easy and cheap; (iii) carotenoids production by haloarchaea can be improved by genetic modification or even by modifying several cultivation aspects such as nutrition, growth pH, temperature, etc.; (iv) carotenoids are needed to support plant and animal life and human well-being; and (v) carotenoids are compounds highly demanded by pharmaceutical, cosmetic and food markets. Several studies about carotenoid production by haloarchaea have been reported so far, most of them focused on pigments isolation or carotenoids production under different culture conditions. However, the understanding of carotenoid metabolism, regulation, and roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. The uses of those haloarchaeal pigments have also been poorly explored. This work summarises what has been described so far about carotenoids production by haloarchaea and their potential uses in biotechnology and biomedicine. In particular, new scientific evidence of improved carotenoid production by one of the better known haloarchaeon (Haloferax mediterranei) is also discussed.
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Affiliation(s)
- Montserrat Rodrigo-Baños
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| | - Inés Garbayo
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - Carlos Vílchez
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - María José Bonete
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| | - Rosa María Martínez-Espinosa
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
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Structural changes in halophilic and non-halophilic proteases in response to chaotropic reagents. Protein J 2015; 33:394-402. [PMID: 25008068 DOI: 10.1007/s10930-014-9571-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Halophilic enzymes have been established for their stability and catalytic abilities under harsh operational conditions. These have been documented to withstand denaturation at high temperature, pH, organic solvents, and chaotropic agents. However, this stability is modulated by salt. The present study targets an important aspect in understanding protein-urea/GdmCl interactions using proteases from halophilic Bacillus sp. EMB9 and non-halophilic subtilisin (Carlsberg) from Bacillus licheniformis as model systems. While, halophilic protease containing 1 % (w/v) NaCl (0.17 M) retained full activity towards urea (8 M), non-halophilic protease lost about 90 % activity under similar conditions. The secondary and tertiary structure were lost in non-halophilic but preserved for halophilic protein. This effect could be due to the possible charge screening and shielding of the protein surface by Ca(2+) and Na(+) ions rendering it stable against denaturation. The dialyzed halophilic protease almost behaved like the non-halophilic counterpart. Incorporation of NaCl (up to 5 %, w/v or 0.85 M) in dialyzed EMB9 protease containing urea/GdmCl, not only helped regain of proteolytic activity but also evaded denaturing action. Deciphering the basis of this salt modulated stability amidst a denaturing milieu will provide guidelines and templates for engineering stable proteins/enzymes for biotechnological applications.
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13
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Sinha R, Khare SK. Protective role of salt in catalysis and maintaining structure of halophilic proteins against denaturation. Front Microbiol 2014; 5:165. [PMID: 24782853 PMCID: PMC3988381 DOI: 10.3389/fmicb.2014.00165] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 03/27/2014] [Indexed: 11/23/2022] Open
Abstract
Search for new industrial enzymes having novel properties continues to be a desirable pursuit in enzyme research. The halophilic organisms inhabiting under saline/ hypersaline conditions are considered as promising source of useful enzymes. Their enzymes are structurally adapted to perform efficient catalysis under saline environment wherein n0n-halophilic enzymes often lose their structure and activity. Haloenzymes have been documented to be polyextremophilic and withstand high temperature, pH, organic solvents, and chaotropic agents. However, this stability is modulated by salt. Although vast amount of information have been generated on salt mediated protection and structure function relationship in halophilic proteins, their clear understanding and correct perspective still remain incoherent. Furthermore, understanding their protein architecture may give better clue for engineering stable enzymes which can withstand harsh industrial conditions. The article encompasses the current level of understanding about haloadaptations and analyzes structural basis of their enzyme stability against classical denaturants.
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Affiliation(s)
- Rajeshwari Sinha
- Department of Chemistry, Indian Institute of Technology Delhi Delhi, India
| | - Sunil K Khare
- Department of Chemistry, Indian Institute of Technology Delhi Delhi, India
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14
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Molecular bases of protein halotolerance. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:850-8. [DOI: 10.1016/j.bbapap.2014.02.018] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 02/18/2014] [Accepted: 02/21/2014] [Indexed: 02/04/2023]
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15
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Qin Y, Huang Z, Liu Z. A novel cold-active and salt-tolerant α-amylase from marine bacterium Zunongwangia profunda: molecular cloning, heterologous expression and biochemical characterization. Extremophiles 2013; 18:271-81. [PMID: 24318109 DOI: 10.1007/s00792-013-0614-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 11/21/2013] [Indexed: 11/28/2022]
Abstract
A novel gene (amyZ) encoding a cold-active and salt-tolerant α-amylase (AmyZ) was cloned from marine bacterium Zunongwangia profunda (MCCC 1A01486) and the protein was expressed in Escherichia coli. The gene has a length of 1785 bp and encodes an α-amylase of 594 amino acids with an estimated molecular mass of 66 kDa by SDS-PAGE. The enzyme belongs to glycoside hydrolase family 13 and shows the highest identity (25%) to the characterized α-amylase TVA II from thermoactinomyces vulgaris R-47. The recombinant α-amylase showed the maximum activity at 35 °C and pH 7.0, and retained about 39% activity at 0 °C. AmyZ displayed extreme salt tolerance, with the highest activity at 1.5 M NaCl and 93% activity even at 4 M NaCl. The catalytic efficiency (k cat/K m) of AmyZ increased from 115.51 (with 0 M NaCl) to 143.30 ml mg(-1) s(-1) (with 1.5 M NaCl) at 35 °C and pH 7.0, using soluble starch as substrate. Besides, the thermostability of the enzyme was significantly improved in the presence of 1.5 M NaCl or 1 mM CaCl2. AmyZ is one of the very few α-amylases that tolerate both high salinity and low temperatures, making it a potential candidate for research in basic and applied biology.
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Affiliation(s)
- Yongjun Qin
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
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16
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Karan R, Capes MD, DasSarma S. Function and biotechnology of extremophilic enzymes in low water activity. AQUATIC BIOSYSTEMS 2012; 8:4. [PMID: 22480329 PMCID: PMC3310334 DOI: 10.1186/2046-9063-8-4] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 02/02/2012] [Indexed: 05/31/2023]
Abstract
Enzymes from extremophilic microorganisms usually catalyze chemical reactions in non-standard conditions. Such conditions promote aggregation, precipitation, and denaturation, reducing the activity of most non-extremophilic enzymes, frequently due to the absence of sufficient hydration. Some extremophilic enzymes maintain a tight hydration shell and remain active in solution even when liquid water is limiting, e.g. in the presence of high ionic concentrations, or at cold temperature when water is close to the freezing point. Extremophilic enzymes are able to compete for hydration via alterations especially to their surface through greater surface charges and increased molecular motion. These properties have enabled some extremophilic enzymes to function in the presence of non-aqueous organic solvents, with potential for design of useful catalysts. In this review, we summarize the current state of knowledge of extremophilic enzymes functioning in high salinity and cold temperatures, focusing on their strategy for function at low water activity. We discuss how the understanding of extremophilic enzyme function is leading to the design of a new generation of enzyme catalysts and their applications to biotechnology.
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Affiliation(s)
- Ram Karan
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
- Institute of Marine and Environmental Technology, University System of Maryland, Baltimore, MD, USA
| | - Melinda D Capes
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
- Institute of Marine and Environmental Technology, University System of Maryland, Baltimore, MD, USA
| | - Shiladitya DasSarma
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
- Institute of Marine and Environmental Technology, University System of Maryland, Baltimore, MD, USA
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17
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Cao Y, Liao L, Xu XW, Oren A, Wang C, Zhu XF, Wu M. Characterization of alcohol dehydrogenase from the haloalkaliphilic archaeon Natronomonas pharaonis. Extremophiles 2008; 12:471-6. [PMID: 18189118 DOI: 10.1007/s00792-007-0133-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2007] [Accepted: 12/02/2007] [Indexed: 11/28/2022]
Abstract
Alcohol dehydrogenase (ADH; EC: 1.1.1.1) is a key enzyme in production and utilization of ethanol. In this study, the gene encoding for ADH of the haloalkaliphilic archaeon Natronomonas pharaonis (NpADH), which has a 1,068-bp open reading frame that encodes a protein of 355 amino acids, was cloned into the pET28b vector and was expressed in Escherichia coli. Then, NpADH was purified by Ni-NTA affinity chromatography. The recombinant enzyme showed a molecular mass of 41.3 kDa by SDS-PAGE. The enzyme was haloalkaliphilic and thermophilic, being most active at 5 M NaCl or 4 M KCl and 70 degrees C, respectively. The optimal pH was 9.0. Zn2+ significantly inhibited activity. The Km value for acetaldehyde was higher than that for ethanol. It was concluded that the physiological role of this enzyme is likely the catalysis of the oxidation of ethanol to acetaldehyde.
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Affiliation(s)
- Yi Cao
- College of Life Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China
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18
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Dodia MS, Rawal CM, Bhimani HG, Joshi RH, Khare SK, Singh SP. Purification and stability characteristics of an alkaline serine protease from a newly isolated Haloalkaliphilic bacterium sp. AH-6. J Ind Microbiol Biotechnol 2007; 35:121-31. [DOI: 10.1007/s10295-007-0273-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Accepted: 10/20/2007] [Indexed: 10/22/2022]
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19
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Madern D, Ebel C. Influence of an anion-binding site in the stabilization of halophilic malate dehydrogenase from Haloarcula marismortui. Biochimie 2007; 89:981-7. [PMID: 17451860 DOI: 10.1016/j.biochi.2007.03.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Accepted: 03/09/2007] [Indexed: 11/30/2022]
Abstract
Halophilic proteins have evolved to be soluble, stable and active in high salt concentration. Crystallographic studies have shown that surface enrichment by acidic amino acids is a common structural feature of halophilic proteins. In addition, ion-binding sites have also been observed in most of the cases. The role of chloride-binding sites in halophilic adaptation was addressed in a site-directed mutagenesis study of tetrameric malate dehydrogenase from Haloarcula marismortui. The mutation of K 205, which is involved in an inter-subunit chloride-binding site, drastically modified the enzyme stability in the presence of KCl, but not in the presence of KF. The oligomeric state of the [K205A] mutant changes with the nature of the anion. At high salt concentration, the [K205A] mutant is a dimer when the anion is a chloride ion, whereas it is a tetramer when the fluoride ion is used. The results highlight the role of anion-binding sites in protein adaptation to high salt conditions.
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Affiliation(s)
- Dominique Madern
- Institut de Biologie Structurale Jean-Pierre Ebel, UMR 5075, CEA, CNRS, Université Joseph Fourier, 41 rue Jules Horowitz, F-38027 Grenoble, France.
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20
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Srimathi S, Jayaraman G, Feller G, Danielsson B, Narayanan PR. Intrinsic halotolerance of the psychrophilic alpha-amylase from Pseudoalteromonas haloplanktis. Extremophiles 2007; 11:505-15. [PMID: 17310272 DOI: 10.1007/s00792-007-0062-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Accepted: 12/27/2006] [Indexed: 10/23/2022]
Abstract
The halotolerance of a cold adapted alpha-amylase from the psychrophilic bacterium Pseudoalteromonas haloplanktis (AHA) was investigated. AHA exhibited hydrolytic activity over a broad range of NaCl concentrations (0.01-4.5 M). AHA showed 28% increased activity in 0.5-2.0 M NaCl compared to that in 0.01 M NaCl. In contrast, the corresponding mesophilic (Bacillus amyloliquefaciens) and thermostable (B. licheniformis) alpha-amylases showed a 39 and 46% decrease in activity respectively. Even at 4.5 M NaCl, 80% of the initial activity was detected for AHA, whereas the mesophilic and thermostable enzymes were inactive. Besides an unaltered fluorescence emission and secondary structure, a 10 degrees C positive shift in the temperature optimum, a stabilization factor of >5 for thermal inactivation and a Delta T(m) of 8.3 degrees C for the secondary structure melting were estimated in 2.7 M NaCl. The higher activation energy, half-life time and T(m) indicated reduced conformational dynamics and increased rigidity in the presence of higher NaCl concentrations. A comparison with the sequences of other halophilic alpha-amylases revealed that AHA also contains higher proportion of small hydrophobic residues and acidic residues resulting in a higher negative surface potential. Thus, with some compromise in cold activity, psychrophilic adaptation has also manifested halotolerance to AHA that is comparable to the halophilic enzymes.
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Affiliation(s)
- Soundararajan Srimathi
- Department of Microbiology, Tuberculosis Research Centre, Mayor Ramanathan Road, Chetput, Chennai, 600 031, India.
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21
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Patel RK, Dodia MS, Joshi RH, Singh SP. Purification and characterization of alkaline protease from a newly isolated haloalkaliphilic Bacillus sp. Process Biochem 2006. [DOI: 10.1016/j.procbio.2006.04.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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22
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Díaz S, Pérez-Pomares F, Pire C, Ferrer J, Bonete MJ. Gene cloning, heterologous overexpression and optimized refolding of the NAD-glutamate dehydrogenase from Haloferax mediterranei. Extremophiles 2005; 10:105-15. [PMID: 16200391 DOI: 10.1007/s00792-005-0478-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2005] [Accepted: 08/10/2005] [Indexed: 11/25/2022]
Abstract
The NAD-dependent glutamate dehydrogenase (GDH) gene from the halophilic archaeon Haloferax mediterranei has been cloned. The analysis of the nucleotide sequence revealed an open reading frame of 1323 bp that encodes a NAD-GDH. The amino acid sequence displayed high homology with those from other sources, especially the highly conserved residues involved in 2-oxoglutarate binding. The expression of this gene in Escherichia coli, the refolding and further characterization, yielded a fully active NAD-GDH with the same features than those found for the wild-type enzyme. This halophilic NAD-GDH showed a highly dependence on salts for both stability and activity, being essential for the refolding of the recombinant enzyme.
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Affiliation(s)
- Susana Díaz
- División de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Alicante, Spain
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