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Akram F, Fatima T, Ul Haq I. Auto-induction, biochemical characterization and application of a novel thermo-alkaline and detergent-stable lipase (S9 peptidase domain) from Thermotoga petrophila as cleaning additive and degrading oil/fat wastes. Bioorg Chem 2024; 151:107658. [PMID: 39033546 DOI: 10.1016/j.bioorg.2024.107658] [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: 04/07/2024] [Revised: 06/29/2024] [Accepted: 07/15/2024] [Indexed: 07/23/2024]
Abstract
A peptidase S9 prolyl oligopeptidase domain from Thermotoga petrophila RKU-1T (TpS9) was over-expressed as an active, soluble and hyperstable lipolytic enzyme in the mesophilic host system. The sequence analysis demonstrated, TpS9 is an esterase/lipase-like protein belongs to alpha/beta (α/β)-hydrolase superfamily with a well-conserved penta-peptide (GLSAG) motif and α/β-hydrolase fold. Various approaches (induction and cultivation) were employed to enrich TpS9 production, 6.04- and 7.26-fold increment was observed with IPTG (0.4 mM) and lactose (200 mM) in the modified 4ZB medium (pH 7.0), but with IPTG-independent auto-induction strategy 9.02-fold augmentation was achieved after 16 h incubation at 24 °C (150 rev min-1). Purified TpS9 showed optimal activity in McIlvaine buffer (pH 6.5) at 80-85 °C, and revealed great thermal (30-85 °C) and pH (6.0-9.0) for 8 h. No obvious constraint was perceived with various metal ions, surfactants, commercial laundry detergents, and chemical modulators. Whereas, TpS9 activity was improved with Ca2+, Mn2+, and Mg2+ by 210 %, 142.5 %, and 134.3 %, respectively. With 2.5 M NaCl (215 %), 50 % (v/v) methanol (140 %), 50 % (v/v) ethanol (126.6 %), 50 % (v/v) n-butanol (122.3 %), 50 % (v/v) isopropanol (120.4 %), 50 % (v/v) acetone (118.6 %) and 50 % (v/v) glycerol (113.2 %) TpS9 activity was also enriched. TpS9 demonstrated great affinity toward natural oils and p-nitrophenyl ester substrates, but showed peak activity with p-nitrophenyl palmitate (3160 U mg-1). Km, Vmax, kcat, Vmax Km-1 and kcat Km-1 of TpS9 with pNPP were 0.421 mM, 4015 µmol mg-1 min-1, 906.4 s-1, 9536.8 min-1, and 2152.96 mM-1 s-1, respectively. Moreover, TPS9 has notable ability to clean stains (5 min) and degrade the animals' fat (3 h). Hence, TpS9 is a favorable candidate as cleaning bio-additive in detergent formulation, fat degradation and various other applications.
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Affiliation(s)
- Fatima Akram
- Dr. Ikram-ul-Haq Institute of Industrial Biotechnology, Government College University, Lahore, Pakistan; Department of Biology, Saint Louis University, St. Louis, MO, USA.
| | - Taseer Fatima
- Dr. Ikram-ul-Haq Institute of Industrial Biotechnology, Government College University, Lahore, Pakistan
| | - Ikram Ul Haq
- Dr. Ikram-ul-Haq Institute of Industrial Biotechnology, Government College University, Lahore, Pakistan; Pakistan Academy of Sciences, Islamabad, Pakistan
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Feng S, Xue M, Xie F, Zhao H, Xue Y. Characterization of Thermotoga maritima Esterase Capable of Hydrolyzing Bis(2-hydroxyethyl) Terephthalate. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:12045-12056. [PMID: 38753963 DOI: 10.1021/acs.jafc.4c01973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
The gene-encoding carboxylesterase (TM1022) from the hyperthermophilic bacterium Thermotoga maritima (T. maritima) was cloned and expressed in Escherichia coli Top10 and BL21 (DE3). Recombinant TM1022 showed the best activity at pH 8.0 and 85 °C and retained 57% activity after 8 h cultivation at 90 °C. TM1022 exhibited good stability at pH 6.0-9.0, maintaining 53% activity after incubation at pH 10.0 and 37 °C for 6 h. The esterase TM1022 exhibited the optimum thermo-alkali stability and kcat/Km (598.57 ± 19.97 s-1mM-1) for pN-C4. TM1022 hydrolyzed poly(ethylene terephthalate) (PET) degradation intermediates, such as bis(2-hydroxyethyl) terephthalate (BHET) and mono(2-hydroxyethyl) terephthalate (MHET). The Km, kcat, and kcat/Km values for BHET were 0.82 ± 0.01 mM, 2.20 ± 0.02 s-1, and 2.67 ± 0.02 mM-1 s-1, respectively; those for MHET were 2.43 ± 0.07 mM, 0.04 ± 0.001 s-1, and 0.02 ± 0.001 mM-1 s-1, respectively. When purified TM1022 was added to the cutinase BhrPETase, hydrolysis of PET from drinking water bottle tops produced pure terephthalic acids (TPA) with 166% higher yield than those obtained after 72 h of incubation with BhrPETase alone as control. The above findings demonstrate that the esterase TM1022 from T. maritima has substantial potential for depolymerizing PET into monomers for reuse.
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Affiliation(s)
- Sizhong Feng
- Department of Food Science and Nutrition, College of Food and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Mengke Xue
- Department of Food Science and Nutrition, College of Food and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Fang Xie
- Department of Food Science and Nutrition, College of Food and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Hongyang Zhao
- Department of Food Science and Nutrition, College of Food and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Yemin Xue
- Department of Food Science and Nutrition, College of Food and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
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Ghattavi S, Homaei A. Marine enzymes: Classification and application in various industries. Int J Biol Macromol 2023; 230:123136. [PMID: 36621739 DOI: 10.1016/j.ijbiomac.2023.123136] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 12/23/2022] [Accepted: 01/01/2023] [Indexed: 01/06/2023]
Abstract
Oceans are regarded as a plentiful and sustainable source of biological compounds. Enzymes are a group of marine biomaterials that have recently drawn more attention because they are produced in harsh environmental conditions such as high salinity, extensive pH, a wide temperature range, and high pressure. Hence, marine-derived enzymes are capable of exhibiting remarkable properties due to their unique composition. In this review, we overviewed and discussed characteristics of marine enzymes as well as the sources of marine enzymes, ranging from primitive organisms to vertebrates, and presented the importance, advantages, and challenges of using marine enzymes with a summary of their applications in a variety of industries. Current biotechnological advancements need the study of novel marine enzymes that could be applied in a variety of ways. Resources of marine enzyme can benefit greatly for biotechnological applications duo to their biocompatible, ecofriendly and high effectiveness. It is beneficial to use the unique characteristics offered by marine enzymes to either develop new processes and products or improve existing ones. As a result, marine-derived enzymes have promising potential and are an excellent candidate for a variety of biotechnology applications and a future rise in the use of marine enzymes is to be anticipated.
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Affiliation(s)
- Saba Ghattavi
- Fisheries Department, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran
| | - Ahmad Homaei
- Department of Marine Biology, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran.
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Lu M, Schneider D, Daniel R. Metagenomic Screening for Lipolytic Genes Reveals an Ecology-Clustered Distribution Pattern. Front Microbiol 2022; 13:851969. [PMID: 35756004 PMCID: PMC9226776 DOI: 10.3389/fmicb.2022.851969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 04/28/2022] [Indexed: 12/02/2022] Open
Abstract
Lipolytic enzymes are one of the most important enzyme types for application in various industrial processes. Despite the continuously increasing demand, only a small portion of the so far encountered lipolytic enzymes exhibit adequate stability and activities for biotechnological applications. To explore novel and/or extremophilic lipolytic enzymes, microbial consortia in two composts at thermophilic stage were analyzed using function-driven and sequence-based metagenomic approaches. Analysis of community composition by amplicon-based 16S rRNA genes and transcripts, and direct metagenome sequencing revealed that the communities of the compost samples were dominated by members of the phyla Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes, and Chloroflexi. Function-driven screening of the metagenomic libraries constructed from the two samples yielded 115 unique lipolytic enzymes. The family assignment of these enzymes was conducted by analyzing the phylogenetic relationship and generation of a protein sequence similarity network according to an integrated classification system. The sequence-based screening was performed by using a newly developed database, containing a set of profile Hidden Markov models, highly sensitive and specific for detection of lipolytic enzymes. By comparing the lipolytic enzymes identified through both approaches, we demonstrated that the activity-directed complements sequence-based detection, and vice versa. The sequence-based comparative analysis of lipolytic genes regarding diversity, function and taxonomic origin derived from 175 metagenomes indicated significant differences between habitats. Analysis of the prevalent and distinct microbial groups providing the lipolytic genes revealed characteristic patterns and groups driven by ecological factors. The here presented data suggests that the diversity and distribution of lipolytic genes in metagenomes of various habitats are largely constrained by ecological factors.
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Affiliation(s)
| | | | - Rolf Daniel
- Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg August University of Göttingen, Göttingen, Germany
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PTCL1-EstA from Paenarthrobacter aurescens TC1, a Candidate for Industrial Application Belonging to the VIII Esterase Family. Catalysts 2022. [DOI: 10.3390/catal12050473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The esterase PTCL1-EstA from Paenarthrobacter aurescens TC1 was expressed in Escherichia coli and characterized. An 1152 bp open reading frame encoding a 383 amino acid polypeptide was successfully expressed, the C-terminally His6-tagged PTCL1-EstA enzyme was purified, and the predicted molecular mass of the purified PTCL1-EstA was 40.6 kDa. The EstA family serine hydrolase PTCL1-EstA belongs to the esterase family VIII, contains esterase-labeled S-C-S-K sequences, and homologous class C beta-lactamase sequences. PTCL1-EstA favored p-nitrophenyl esters with C2-C6 chain lengths, but it was also able to hydrolyze long-chain p-nitrophenyl esters. Homology modelling and substrate docking predicted that Ser59 was an active site residue in PTCL1-EstA, as well as Tyr148, Ala325, and Asp323, which are critical in catalyzing the enzymatic reaction of p-nitrophenyl esters. PTCL1-EstA reached the highest specific activity against p-nitrophenyl butyrate (C4) at pH 7.0 and 45 °C but revealed better thermal stability at 40 °C and maintained high relative enzymatic activity and stability at pH 5.0–9.0. Fermentation medium optimization for PTCL1-EstA increased the enzyme activity to 510.76 U/mL, tapping the potential of PTCL1-EstA for industrial production.
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Tulsani NJ, Mishra P, Jakhesara SJ, Srivastava S, Jyotsana B, Dafale NA, Patil NV, Purohit HJ, Joshi CG. Isolation, purification and characterization of a novel esterase from camel rumen metagenome. Protein Expr Purif 2021; 187:105941. [PMID: 34273540 DOI: 10.1016/j.pep.2021.105941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 10/20/2022]
Abstract
Bacterial esterases are gaining the importance in pharmaceuticals and agrochemical industries due to their excellent biocatalytic properties and a wide range of applications. In the present study, a novel gene encoding an esterase (designated as Est-CR) was identified from shotgun metagenomic sequencing data of camel rumen (Camelus dromedarius) liquor. The open reading frame consisted of 1,224bp, which showed 84.03% sequence identity to Bacteroidales bacterium, corresponding to a protein of 407 amino acids and has a catalytic domain belonging to an esterase. Est-CR belonged to family V with GLSMG domain. The purified enzyme with a molecular mass of 62.64 kDa was checked on SDS-PAGE, and its expression was confirmed by western blotting. The enzyme was active and stable over a broad range of temperature (35-65 °C), displayed the maximum activity at 50 °C and pH 7.0. Individually all metal ions inhibited the enzyme activity, while in combination, K2+, Ca2+, Mg2+ and Mn2+ metal ions enhanced the enzyme activity. The detergents strongly inhibited the activity, while EDTA (10 mM) increased the activity of the Est-CR enzyme. The enzyme showed specificity to short-chain substrates and displayed an optimum activity against butyrate ester. This novel enzyme might serve as a promising candidate to meet some harsh industrial processes enzymatic needs.
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Affiliation(s)
- Nilam J Tulsani
- Department of Animal Biotechnology, College of Veterinary Science and Animal Husbandry, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Priyaranjan Mishra
- Department of Animal Genetic and Breeding, College of Veterinary Science and Animal Husbandry, Anand Agricultural University, Anand, Gujarat, 388001, India
| | - Subhash J Jakhesara
- Department of Animal Biotechnology, College of Veterinary Science and Animal Husbandry, Anand Agricultural University, Anand, Gujarat, 388001, India.
| | - Shweta Srivastava
- Environmental Genomic Division, CSIR-National Environmental Engineering Research Institute (NEERI), Nehru Marg, Nagpur, 440020, India
| | - Basanti Jyotsana
- ICAR-National Research Centre on Camel (NRCC) Jorbeer, Bikaner, Rajasthan, 334001, India
| | - Nishant A Dafale
- Environmental Genomic Division, CSIR-National Environmental Engineering Research Institute (NEERI), Nehru Marg, Nagpur, 440020, India
| | - Niteen V Patil
- ICAR-Central Arid Zone Research Institute, Jodhpur, Rajasthan, 342003, India
| | - Hemant J Purohit
- Environmental Genomic Division, CSIR-National Environmental Engineering Research Institute (NEERI), Nehru Marg, Nagpur, 440020, India
| | - Chaitanya G Joshi
- Department of Animal Biotechnology, College of Veterinary Science and Animal Husbandry, Anand Agricultural University, Anand, Gujarat, 388001, India; Gujarat Biotechnology Research Canter, MS Building, Block B & D, 6th Floor, GH Road, Sector-11, Gandhinagar, Gujarat, 382001, India
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Sorokina KN, Samoylova YV, Parmon VN. Thermostable Esterase estUT1 from Ureibacillus thermosphaericus: Effect of TrxA Tag on the Enzyme Properties. CATALYSIS IN INDUSTRY 2020. [DOI: 10.1134/s2070050420020099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Sukul P, Lupilov N, Leichert LI. Characterization of ML-005, a Novel Metaproteomics-Derived Esterase. Front Microbiol 2018; 9:1925. [PMID: 30210461 PMCID: PMC6119806 DOI: 10.3389/fmicb.2018.01925] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 07/30/2018] [Indexed: 01/06/2023] Open
Abstract
A novel gene encoding for a lipolytic enzyme, designated ML-005, was recently identified using a functional metaproteomics approach. We heterologously expressed this protein in Escherichia coli and biochemically characterized it. ML-005 exhibited lipolytic activity toward short-chained substrates with the preferred substrate being p-nitrophenyl-butyrate, suggesting that ML-005 is an esterase. According to homology analysis and site-directed mutagenesis, the catalytic triad of the enzyme was identified as Ser-99, Asp-164, and His-191. Its optimal pH was determined to be at pH 8. Optimal activity was observed at 45°C. It also exhibited temperature, pH and salt tolerance. Residual relative activity after incubating at 50–60°C for 360 min was above 80% of its initial activity. It showed tolerance over a broad range of pH (5–12) and retained most of its initial activity. Furthermore, incubating ML-005 in 1 – 5M NaCl solution had negligible effect on its activity. DTT, EDTA, and ß-mercaptoethanol had no significant effect on ML-005’s activity. However, addition of PMSF led to almost complete inactivation consistent with ML-005 being a serine hydrolase. ML-005 remains stable in the presence of a range of metal ions, but addition of Cu2+ significantly reduces its relative activity. Organic solvents have an inhibitory effect on ML-005, but it retained 21% of activity in 10% methanol. SDS had the most pronounced inhibitory effect on ML-005 among all detergents tested and completely inactivated it. Furthermore, the Vmax of ML-005 was determined to be 59.8 μM/min along with a Km of 137.9 μM. The kcat of ML-005 is 26 s-1 and kcat/Km is 1.88 × 105 M-1 s-1.
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Affiliation(s)
- Premankur Sukul
- Department of Microbial Biochemistry, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
| | - Natalie Lupilov
- Department of Microbial Biochemistry, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
| | - Lars I Leichert
- Department of Microbial Biochemistry, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
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Noby N, Saeed H, Embaby AM, Pavlidis IV, Hussein A. Cloning, expression and characterization of cold active esterase (EstN7) from Bacillus cohnii strain N1: A novel member of family IV. Int J Biol Macromol 2018; 120:1247-1255. [PMID: 30063933 DOI: 10.1016/j.ijbiomac.2018.07.169] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/25/2018] [Accepted: 07/26/2018] [Indexed: 01/11/2023]
Abstract
Esterases and lipases from extremophiles have attracted great attention due to their unique characteristics and wide applications. In the present study, an open reading frame (ORF) encoding a novel cold active esterase (EstN7) from Bacillus cohnii strain N1 was cloned and expressed in Escherichia coli. The full-length esterase gene encoding a protein of 320 amino acids with estimated molecular weight of 37.0 kDa. Amino acid sequence analysis revealed that the EstN7 belongs to family IV lipases with a characteristic penta-peptide motif (GXSXG), the catalytic triad Ser, Asp, His and the conserved HGGG motif of the family IV. The recombinant enzyme was purified to apparent homogeneity using nickel-affinity chromatography with a purification fold of 5 and recovery 94.5%. The specific activity of the purified enzyme was 336.89 U/mg. The recombinant EstN7 showed optimal activity at 5 °C moreover, EstN7 displayed full robust stability in the presence of wide range of organic solvents. The purified enzyme had Km and Vmax of 45 ± 0.019 μM and 1113 μmol min-1 mg-1, respectively on p-NP-acetate. These promising characteristics of the recombinant EstN7 would underpin its possible usage with high potential in the synthesis of fragile compounds in pharmaceutical industries.
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Affiliation(s)
- Nehad Noby
- Department of Biotechnology, Institute of Graduate Studies and Research, Alexandria University, Alexandria, Egypt.
| | - Hesham Saeed
- Department of Biotechnology, Institute of Graduate Studies and Research, Alexandria University, Alexandria, Egypt.
| | - Amira M Embaby
- Department of Biotechnology, Institute of Graduate Studies and Research, Alexandria University, Alexandria, Egypt
| | | | - Ahmed Hussein
- Department of Biotechnology, Institute of Graduate Studies and Research, Alexandria University, Alexandria, Egypt
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Guo YY, Yu XW, Xu Y. Cloning, expression and characterization of two thermostable esterases from Aquifex aeolicus VF5. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2017.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Functional Characterization of a Marine Bacillus Esterase and its Utilization in the Stereo-Selective Production of D-Methyl Lactate. Appl Biochem Biotechnol 2016; 180:1467-1481. [PMID: 27364331 DOI: 10.1007/s12010-016-2180-y] [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: 03/25/2016] [Accepted: 06/22/2016] [Indexed: 10/21/2022]
Abstract
Chiral lactic acid and its ester derivatives are crucial building blocks and platforms in the generation of high value-added drugs, fine chemicals and functional materials. Optically pure D-lactic acid and its ester derivatives cannot be directly generated from fermentation and are quite expensive. Herein, we identified, heterologously expressed and functionally characterized one Bacillus esterase BSE01701 from the deep sea of the Indian Ocean. Esterase BSE01701 could enzymatically resolve inexpensive racemic methyl lactate and generate chiral D-methyl lactate. The enantiomeric excess of desired chiral D-methyl lactate and the substrate conversion could reach over 99 % and 60 %, respectively, after process optimization. Notably, the addition of 60 % (v/v) organic co-solvent heptane could greatly improve both the enantiomeric excess of D-methyl lactate and the conversion. BSE01701 was a very promising marine microbial esterase in the generation of chiral chemicals in industry.
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De Santi C, Altermark B, Pierechod MM, Ambrosino L, de Pascale D, Willassen NP. Characterization of a cold-active and salt tolerant esterase identified by functional screening of Arctic metagenomic libraries. BMC BIOCHEMISTRY 2016; 17:1. [PMID: 26782782 PMCID: PMC4717575 DOI: 10.1186/s12858-016-0057-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 01/14/2016] [Indexed: 12/26/2022]
Abstract
BACKGROUND The use of metagenomics in enzyme discovery constitutes a powerful approach to access to genomes of unculturable community of microorganisms and isolate novel valuable biocatalysts for use in a wide range of biotechnological and pharmaceutical fields. RESULTS Here we present a novel esterase gene (lip3) identified by functional screening of three fosmid metagenomic libraries, constructed from three marine sediment samples. The sequenced positive fosmid revealed an enzyme of 281 amino acids with similarity to class 3 lipases. The 3D modeling of Lip3 was generated by homology modeling on the basis of four lipases templates [PDB ID: 3O0D, 3NGM, 3G7N, 2QUB] to unravel structural features of this novel enzyme. The catalytic triad of Lip3 was predicted to be Asp207, His267 and the catalytic nucleophile Ser150 in a conserved pentapeptide (GXSXG). The 3D model highlighted the presence of a one-helix lid able to regulate the access of the substrate to the active site when the enzyme binds a hydrophobic interface. Moreover an analysis of the external surface of Lip3 model showed that the majority of the surface regions were hydrophobic (59.6 %) compared with homologous lipases (around 35 %) used as templates. The recombinant Lip3 esterase, expressed and purified from Escherichia coli, preferentially hydrolyzed short and medium length p-nitrophenyl esters with the best substrate being p-nitrophenyl acetate. Further characterization revealed a temperature optimum of 35 °C and a pH optimum of 8.0. Lip3 exhibits a broad temperature stability range and tolerates the presence of DTT, EDTA, PMSF, β-mercaptoethanol and high concentrations of salt. The enzyme was also highly activated by NaCl. CONCLUSIONS The biochemical characterization and homology model reveals a novel esterase originating from the marine Arctic metagenomics libraries with features of a cold-active, relatively thermostable and highly halotolerant enzyme. Taken together, these results suggest that this esterase could be a highly valuable candidate for biotechnological applications such as organic synthesis reactions and cheese ripening processes.
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Affiliation(s)
- Concetta De Santi
- NorStruct, Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, Tromsø, Norway.
| | - Bjørn Altermark
- NorStruct, Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, Tromsø, Norway.
| | - Marcin Miroslaw Pierechod
- NorStruct, Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, Tromsø, Norway.
| | - Luca Ambrosino
- Institute of Protein Biochemistry, National Research Council, Naples, Italy.
| | | | - Nils-Peder Willassen
- NorStruct, Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, Tromsø, Norway.
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