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Aguirre-Sampieri S, Casañal A, Emsley P, Garza-Ramos G. Cryo-EM structure of bacterial nitrilase reveals insight into oligomerization, substrate recognition, and catalysis. J Struct Biol 2024; 216:108093. [PMID: 38615726 PMCID: PMC7616060 DOI: 10.1016/j.jsb.2024.108093] [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: 01/17/2024] [Revised: 03/26/2024] [Accepted: 04/12/2024] [Indexed: 04/16/2024]
Abstract
Many enzymes can self-assemble into higher-order structures with helical symmetry. A particularly noteworthy example is that of nitrilases, enzymes in which oligomerization of dimers into spiral homo-oligomers is a requirement for their enzymatic function. Nitrilases are widespread in nature where they catalyze the hydrolysis of nitriles into the corresponding carboxylic acid and ammonia. Here, we present the Cryo-EM structure, at 3 Å resolution, of a C-terminal truncate nitrilase from Rhodococcus sp. V51B that assembles in helical filaments. The model comprises a complete turn of the helical arrangement with a substrate-intermediate bound to the catalytic cysteine. The structure was solved having added the substrate to the protein. The length and stability of filaments was made more substantial in the presence of the aromatic substrate, benzonitrile, but not for aliphatic nitriles or dinitriles. The overall structure maintains the topology of the nitrilase family, and the filament is formed by the association of dimers in a chain-like mechanism that stabilizes the spiral. The active site is completely buried inside each monomer, while the substrate binding pocket was observed within the oligomerization interfaces. The present structure is in a closed configuration, judging by the position of the lid, suggesting that the intermediate is one of the covalent adducts. The proximity of the active site to the dimerization and oligomerization interfaces, allows the dimer to sense structural changes once the benzonitrile was bound, and translated to the rest of the filament, stabilizing the helical structure.
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Affiliation(s)
- Sergio Aguirre-Sampieri
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica, Circuito Escolar S/N, Ciudad Universitaria, CDMX, Mexico
| | - Ana Casañal
- Human Technopole, Palazzo Italia, Viale Rita Levi‑Montalcini, 1, 20157 Milan, Italy
| | - Paul Emsley
- MRC Laboratory of Molecular Biology, Structural Studies Division, Francis Crick Avenue, CB2 0QH Cambridge, England
| | - Georgina Garza-Ramos
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica, Circuito Escolar S/N, Ciudad Universitaria, CDMX, Mexico.
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Yu L, Li T, Li H, Ma M, Li L, Lin S. In Situ Molecular Ecological Analyses Illuminate Distinct Factors Regulating Formation and Demise of a Harmful Dinoflagellate Bloom. Microbiol Spectr 2023; 11:e0515722. [PMID: 37074171 PMCID: PMC10269597 DOI: 10.1128/spectrum.05157-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 03/27/2023] [Indexed: 04/20/2023] Open
Abstract
The development and demise of a harmful algal bloom (HAB) are generally regulated by multiple processes; identifying specific critical drivers for a specific bloom is important yet challenging. Here, we conducted a whole-assemblage molecular ecological study on a dinoflagellate bloom to address the hypothesis that energy and nutrient acquisition, defense against grazing and microbial attacks, and sexual reproduction are critical to the rise and demise of the bloom. Microscopic and molecular analyses identified the bloom-causing species as Karenia longicanalis and showed that the ciliate Strombidinopsis sp. was dominant in a nonbloom plankton community, whereas the diatom Chaetoceros sp. dominated the after-bloom community, along with remarkable shifts in the community structure for both eukaryotes and prokaryotes. Metatranscriptomic analysis indicated that heightened energy and nutrient acquisition in K. longicanalis significantly contributed to bloom development. In contrast, active grazing by the ciliate Strombidinopsis sp. and attacks by algicidal bacteria (Rhodobacteracea, Cryomorphaceae, and Rhodobacteracea) and viruses prevented (at nonbloom stage) or collapsed the bloom (in after-bloom stage). Additionally, nutrition competition by the Chaetoceros diatoms plausibly contributed to bloom demise. The findings suggest the importance of energy and nutrients in promoting this K. longicanalis bloom and the failure of antimicrobial defense and competition of diatoms as the major bloom suppressor and terminator. This study provides novel insights into bloom-regulating mechanisms and the first transcriptomic data set of K. longicanalis, which will be a valuable resource and essential foundation for further elucidation of bloom regulators of this and related species of Kareniaceae in the future. IMPORTANCE HABs have increasingly occurred and impacted human health, aquatic ecosystems, and coastal economies. Despite great efforts, the factors that drive the development and termination of a bloom are poorly understood, largely due to inadequate in situ data about the physiology and metabolism of the causal species and the community. Using an integrative molecular ecological approach, we determined that heightened energy and nutrient acquisition promoted the bloom, while resource allocation in defense and failure to defend against grazing and microbial attacks likely prevented or terminated the bloom. Our findings reveal the differential roles of multiple abiotic and biotic environmental factors in driving the formation or demise of a toxic dinoflagellate bloom, suggesting the importance of a balanced biodiverse ecosystem in preventing a dinoflagellate bloom. The study also demonstrates the power of whole-assemblage metatranscriptomics coupled to DNA barcoding in illuminating plankton ecological processes and the underlying species and functional diversities.
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Affiliation(s)
- Liying Yu
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Central Laboratory, Second Affiliated Hospital of Fujian Medical University, Quanzhou, China
| | - Tangcheng Li
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Hongfei Li
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Minglei Ma
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Ling Li
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Senjie Lin
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Department of Marine Sciences, University of Connecticut, Groton, Connecticut, USA
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Kumar A, Shahul R, Singh R, Kumar S, Kumar A, Mehta PK. Geobacillus thermoleovorans MTCC 13131: An Amide-Hydrolyzing Thermophilic Bacterium Isolated from a Hot Spring of Manikaran. Indian J Microbiol 2022; 62:618-626. [PMID: 36458220 PMCID: PMC9705672 DOI: 10.1007/s12088-022-01042-9] [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: 08/23/2022] [Accepted: 10/07/2022] [Indexed: 11/05/2022] Open
Abstract
Geobacillus thermoleovorans MTCC 13131, an amide hydrolyzing bacteria was isolated from a hot spring in Himachal Pradesh and identified through 16S rRNA gene sequence analysis. The amidase derived from this bacterium exhibited hydrolyzing catalytic ability against aliphatic and aromatic amides. The isolate was characterized for morphological and biochemical properties. Further, the production of amidase enzyme from this isolate was evaluated using approach of one-variable-at-a-time and response surface method. The Response Surface Methodology based study indicated the importance of nitrogen sources and growth period for amidase production. Optimal production was achieved at a temperature 55 °C, and production pH 7.5 in the production medium comprising diammonium hydrogen phosphate (0.4%), peptone (0.45%) and yeast extract (0.3%). The wide substrate affinity of the strain suggests its potential role in biotransformation of amides to corresponding acids of industrial significance along with its strong capacity to degrade the toxic amide in polluted environmental samples. Supplementary Information The online version contains supplementary material available at 10.1007/s12088-022-01042-9.
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Affiliation(s)
- Arun Kumar
- Center for Molecular Biology, Central University of Jammu, Bagla, Rahya Suchani, Jammu, Jammu and Kashmir 181143 India
| | - Refana Shahul
- Center for Molecular Biology, Central University of Jammu, Bagla, Rahya Suchani, Jammu, Jammu and Kashmir 181143 India
| | - Rajendra Singh
- Environmental Energy Engineering, College of Engineering, University of Suwon, Hwaseong, 18323 Republic of Korea
| | - Sanjay Kumar
- Department of Life Sciences, School of Basics Sciences and Research, Sharda University, Greater Noida, Uttar Pradesh 201310 India
| | - Ashok Kumar
- Center for Molecular Biology, Central University of Jammu, Bagla, Rahya Suchani, Jammu, Jammu and Kashmir 181143 India
| | - Praveen Kumar Mehta
- Center for Molecular Biology, Central University of Jammu, Bagla, Rahya Suchani, Jammu, Jammu and Kashmir 181143 India
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Genomic attributes of thermophilic and hyperthermophilic bacteria and archaea. World J Microbiol Biotechnol 2022; 38:135. [PMID: 35695998 DOI: 10.1007/s11274-022-03327-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/31/2022] [Indexed: 10/18/2022]
Abstract
Thermophiles and hyperthermophiles are immensely useful in understanding the evolution of life, besides their utility in environmental and industrial biotechnology. Advancements in sequencing technologies have revolutionized the field of microbial genomics. The massive generation of data enhances the sequencing coverage multi-fold and allows to analyse the entire genomic features of microbes efficiently and accurately. The mandate of a pure isolate can also be bypassed where whole metagenome-assembled genomes and single cell-based sequencing have fulfilled the majority of the criteria to decode various attributes of microbial genomes. A boom has, therefore, been seen in analysing the extremophilic bacteria and archaea using sequence-based approaches. Due to extensive sequence analysis, it becomes easier to understand the gene flow and their evolution among the members of bacteria and archaea. For instance, sequencing unveiled that Thermotoga maritima shares around 24% of genes of archaeal origin. Comparative and functional genomics provide an analytical view to understanding the microbial diversity of thermophilic bacteria and archaea, their interactions with other microbes, their adaptations, gene flow, and evolution over time. In this review, the genomic features of thermophilic bacteria and archaea are dealt with comprehensively.
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The structures of the C146A variant of the amidase from Pyrococcus horikoshii bound to glutaramide and acetamide suggest the basis of amide recognition. J Struct Biol 2022; 214:107859. [DOI: 10.1016/j.jsb.2022.107859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 04/07/2022] [Accepted: 04/12/2022] [Indexed: 11/23/2022]
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Wu Z, Liu C, Zhang Z, Zheng R, Zheng Y. Amidase as a versatile tool in amide-bond cleavage: From molecular features to biotechnological applications. Biotechnol Adv 2020; 43:107574. [PMID: 32512219 DOI: 10.1016/j.biotechadv.2020.107574] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 05/31/2020] [Accepted: 06/01/2020] [Indexed: 12/27/2022]
Abstract
Amidases (EC 3. 5. 1. X) are versatile biocatalysts for synthesis of chiral carboxylic acids, α-amino acids and amides due to their hydrolytic and acyl transfer activity towards the C-N linkages. They have been extensively exploited and studied during the past years for their high specific activity and excellent enantioselectivity involved in various biotechnological applications in pharmaceutical and agrochemical industries. Additionally, they have attracted considerable attentions in biodegradation and bioremediation owing to environmental pressures. Motivated by industrial demands, crystallographic investigations and catalytic mechanisms of amidases based on structural biology have witnessed a dramatic promotion in the last two decades. The protein structures showed that different types of amidases have their typical stuctural elements, such as the conserved AS domains in signature amidases and the typical architecture of metal-associated active sites in acetamidase/formamidase family amidases. This review provides an overview of recent research advances in various amidases, with a focus on their structural basis of phylogenetics, substrate specificities and catalytic mechanisms as well as their biotechnological applications. As more crystal structures of amidases are determined, the structure/function relationships of these enzymes will also be further elucidated, which will facilitate molecular engineering and design of amidases to meet industrial requirements.
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Affiliation(s)
- Zheming Wu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
| | - Changfeng Liu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
| | - Zhaoyu Zhang
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
| | - Renchao Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
| | - Yuguo Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China; The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
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Cabrera MÁ, Blamey JM. Biotechnological applications of archaeal enzymes from extreme environments. Biol Res 2018; 51:37. [PMID: 30290805 PMCID: PMC6172850 DOI: 10.1186/s40659-018-0186-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 09/25/2018] [Indexed: 11/10/2022] Open
Abstract
To date, many industrial processes are performed using chemical compounds, which are harmful to nature. An alternative to overcome this problem is biocatalysis, which uses whole cells or enzymes to carry out chemical reactions in an environmentally friendly manner. Enzymes can be used as biocatalyst in food and feed, pharmaceutical, textile, detergent and beverage industries, among others. Since industrial processes require harsh reaction conditions to be performed, these enzymes must possess several characteristics that make them suitable for this purpose. Currently the best option is to use enzymes from extremophilic microorganisms, particularly archaea because of their special characteristics, such as stability to elevated temperatures, extremes of pH, organic solvents, and high ionic strength. Extremozymes, are being used in biotechnological industry and improved through modern technologies, such as protein engineering for best performance. Despite the wide distribution of archaea, exist only few reports about these microorganisms isolated from Antarctica and very little is known about thermophilic or hyperthermophilic archaeal enzymes particularly from Antarctica. This review summarizes current knowledge of archaeal enzymes with biotechnological applications, including two extremozymes from Antarctic archaea with potential industrial use, which are being studied in our laboratory. Both enzymes have been discovered through conventional screening and genome sequencing, respectively.
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Affiliation(s)
- Ma Ángeles Cabrera
- Fundación Científica y Cultural Biociencia, José Domingo Cañas, 2280, Santiago, Chile.,Facultad de Química y Biología, Universidad de Santiago de Chile, Avenida Libertador Bernardo O´Higgins, 3363, Santiago, Chile
| | - Jenny M Blamey
- Fundación Científica y Cultural Biociencia, José Domingo Cañas, 2280, Santiago, Chile. .,Facultad de Química y Biología, Universidad de Santiago de Chile, Avenida Libertador Bernardo O´Higgins, 3363, Santiago, Chile.
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Ismailsab M, T. R. M, Reddy PV, M. S, Nayak AS, Karegoudar TB. Biotransformation of aromatic and heterocyclic amides by amidase of whole cells of Rhodococcus sp. MTB5: Biocatalytic characterization and substrate specificity. BIOCATAL BIOTRANSFOR 2017. [DOI: 10.1080/10242422.2017.1282467] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Mukram Ismailsab
- Department of Biochemistry, Gulbarga University, Kalaburagi, India
| | - Monisha T. R.
- Department of Biochemistry, Gulbarga University, Kalaburagi, India
| | - Pooja V. Reddy
- Department of Biochemistry, Gulbarga University, Kalaburagi, India
| | - Santoshkumar M.
- Department of Biochemistry, Gulbarga University, Kalaburagi, India
| | - Anand S. Nayak
- Department of Biochemistry, Gulbarga University, Kalaburagi, India
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Bedade DK, Singhal RS. Isolation and Characterization of Acrylamidase from Arthrobacter sp. DBV1 and Its Ability to Biodegrade Acrylamide. Appl Biochem Biotechnol 2016; 182:570-585. [PMID: 27924498 DOI: 10.1007/s12010-016-2345-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/24/2016] [Indexed: 10/20/2022]
Abstract
Although acrylamide finds diverse industrial applications, its presence in the environment is hazardous due to its carcinogenic, neurotoxic, and teratogenic properties. In spite of the general toxicity of acrylamide in the monomer form, some microorganisms are able to use it as a source of energy by catabolizing it to ammonia and acrylic acid by means of acrylamidase (EC 3.5.1.4). The present work reports on a novel soil isolate as an acrylamide-degrading bacteria. Based on biochemical characterization and 16S ribosomal RNA (rRNA) gene sequence, the bacterial strain was identified as Gram-positive Arthrobacter sp. DBV1. The optimum growth conditions were found to be temperature (30 °C) and pH 6.0 to 7.0. Evaluation of the effect of concentration of acrylamide (10-50 mM) incorporated into minimal medium showed maximum growth of Arthrobacter sp. DBV1 at 30 mM acrylamide. The biodegradation of acrylamide was confirmed by HPLC analysis. Acrylamidase was isolated and characterized for temperature and pH optima, substrate specificity by using different amides, and the effect of different activators/inhibitors such as metal ions and amino acids. These finding suggests that the strain could be attractive for biodegradation of acrylamide from the environment and also possibly from foods containing preformed acrylamide.
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Affiliation(s)
- Dattatray K Bedade
- Department of Food Engineering and Technology, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai, 400019, India
| | - Rekha S Singhal
- Department of Food Engineering and Technology, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai, 400019, India.
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Identification and characterization of a thermostable and cobalt-dependent amidase from Burkholderia phytofirmans ZJB-15079 for efficient synthesis of (R)-3,3,3-trifluoro-2-hydroxy-2-methylpropionic acid. Appl Microbiol Biotechnol 2016; 101:1953-1964. [DOI: 10.1007/s00253-016-7921-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 09/20/2016] [Accepted: 10/05/2016] [Indexed: 10/20/2022]
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Ruan LT, Zheng RC, Zheng YG. Mining and characterization of two amidase signature family amidases from Brevibacterium epidermidis ZJB-07021 by an efficient genome mining approach. Protein Expr Purif 2016; 126:16-25. [DOI: 10.1016/j.pep.2016.05.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/02/2016] [Accepted: 05/10/2016] [Indexed: 11/28/2022]
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Ruan LT, Zheng RC, Zheng YG, Shen YC. Purification and characterization of R -stereospecific amidase from Brevibacterium epidermidis ZJB-07021. Int J Biol Macromol 2016; 86:893-900. [DOI: 10.1016/j.ijbiomac.2016.02.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 02/05/2016] [Accepted: 02/06/2016] [Indexed: 11/25/2022]
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Guo FM, Wu JP, Yang LR, Xu G. Soluble and functional expression of a recombinant enantioselective amidase from Klebsiella oxytoca KCTC 1686 in Escherichia coli and its biochemical characterization. Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.05.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Li X, Fu L, Li Z, Ma X, Xiao X, Xu J. Genetic tools for the piezophilic hyperthermophilic archaeon Pyrococcus yayanosii. Extremophiles 2014; 19:59-67. [PMID: 25391810 DOI: 10.1007/s00792-014-0705-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/28/2014] [Indexed: 11/30/2022]
Abstract
The hyperthermophile Pyrococcus yayanosii CH1 is the only high-pressure-requiring microorganism obtained thus far within the archaea domain or among all non-psychrophiles in any domain. In this study, we developed a genetic manipulation system for P. yayanosii after first isolating a facultatively piezophilic derivative strain, designated P. yayanosii A1. The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase gene was overexpressed in strain P. yayanosii A1 and was demonstrated to confer host cell resistance against simvastatin. Furthermore, using simvastatin as a selection marker, the endogenous pyrF of P. yayanosii A1 was disrupted through homologous recombination, thus generating the additional host strain P. yayanosii A2 (ΔpyrF). A markerless gene disruption vector was constructed by incorporating a pyrF-sim (R) cassette that enables the combined use of simvastatin resistance for positive selection and 5-FOA for counter selection. The utility of this versatile disruption system was demonstrated by deleting the carbon-nitrogen hydrolase of P. yayanosii strain A1. These results demonstrate that a variety of genetic tools are now in place to study unknown gene function and the molecular mechanisms of piezophilic adaptation in P. yayanosii.
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Affiliation(s)
- Xuegong Li
- Institute of Oceanology, Shanghai Jiao Tong University, Minhang Dongchuan Road 800, Shanghai, 200240, China
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