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  1. Article ; Online: Loss of Astrocytic µ Opioid Receptors Exacerbates Aversion Associated with Morphine Withdrawal in Mice: Role of Mitochondrial Respiration.

    Murlanova, Kateryna / Jouroukhin, Yan / Novototskaya-Vlasova, Ksenia / Huseynov, Shovgi / Pletnikova, Olga / Morales, Michael J / Guan, Yun / Kamiya, Atsushi / Bergles, Dwight E / Dietz, David M / Pletnikov, Mikhail V

    Cells

    2023  Volume 12, Issue 10

    Abstract: Astrocytes express mu/µ opioid receptors, but the function of these receptors remains poorly understood. We evaluated the effects of astrocyte-restricted knockout of µ opioid receptors on reward- and aversion-associated behaviors in mice chronically ... ...

    Abstract Astrocytes express mu/µ opioid receptors, but the function of these receptors remains poorly understood. We evaluated the effects of astrocyte-restricted knockout of µ opioid receptors on reward- and aversion-associated behaviors in mice chronically exposed to morphine. Specifically, one of the floxed alleles of the
    MeSH term(s) Mice ; Animals ; Morphine/adverse effects ; Astrocytes ; Receptors, Opioid ; Narcotic Antagonists/pharmacology ; Naloxone/pharmacology ; Mice, Knockout ; Receptors, Opioid, mu/genetics
    Chemical Substances Morphine (76I7G6D29C) ; Receptors, Opioid ; Narcotic Antagonists ; Naloxone (36B82AMQ7N) ; Receptors, Opioid, mu
    Language English
    Publishing date 2023-05-17
    Publishing country Switzerland
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2661518-6
    ISSN 2073-4409 ; 2073-4409
    ISSN (online) 2073-4409
    ISSN 2073-4409
    DOI 10.3390/cells12101412
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Inflammatory response to retrotransposons drives tumor drug resistance that can be prevented by reverse transcriptase inhibitors.

    Novototskaya-Vlasova, Ksenia A / Neznanov, Nickolay S / Molodtsov, Ivan / Hall, Brandon M / Commane, Mairead / Gleiberman, Anatoli S / Murray, Jayne / Haber, Michelle / Norris, Murray D / Leonova, Katerina I / Gudkov, Andrei V

    Proceedings of the National Academy of Sciences of the United States of America

    2022  Volume 119, Issue 49, Page(s) e2213146119

    Abstract: Activation of endogenous retrotransposons frequently occurs in cancer cells and contributes to tumor genomic instability. To test whether inhibition of retrotranspositions has an anticancer effect, we used treatment with the nucleoside reverse ... ...

    Abstract Activation of endogenous retrotransposons frequently occurs in cancer cells and contributes to tumor genomic instability. To test whether inhibition of retrotranspositions has an anticancer effect, we used treatment with the nucleoside reverse transcriptase inhibitor (NRTI) stavudine (STV) in mouse cancer models, MMTV-HER2/Neu and Th-MYCN, that spontaneously develop breast cancer and neuroblastoma, respectively. In both cases, STV in drinking water did not affect tumor incidence nor demonstrate direct antitumor effects. However, STV dramatically extended progression-free survival in both models following an initial complete response to chemotherapy. To approach the mechanism underlying this phenomenon, we analyzed the effect of NRTI on the selection of treatment-resistant variants in tumor cells in culture. Cultivation of mouse breast carcinoma 4T1 in the presence of STV dramatically reduced the frequency of cells capable of surviving treatment with anticancer drugs. Global transcriptome analysis demonstrated that the acquisition of drug resistance by 4T1 cells was accompanied by an increase in the constitutive activity of interferon type I and NF-κB pathways and an elevated expression of LINE-1 elements, which are known to induce inflammatory responses via their products of reverse transcription. Treatment with NRTI reduced NF-κB activity and reverted drug resistance. Furthermore, the inducible expression of LINE-1 stimulated inflammatory response and increased the frequency of drug-resistant variants in a tumor cell population. These results indicate a mechanism by which retrotransposon desilencing can stimulate tumor cell survival during treatment and suggest reverse transcriptase inhibition as a potential therapeutic approach for targeting the development of drug-resistant cancers.
    MeSH term(s) Animals ; Mice ; Reverse Transcriptase Inhibitors/pharmacology ; Retroelements/genetics ; NF-kappa B ; Drug Resistance, Neoplasm/genetics ; Long Interspersed Nucleotide Elements
    Chemical Substances Reverse Transcriptase Inhibitors ; Retroelements ; NF-kappa B
    Language English
    Publishing date 2022-11-30
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2213146119
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Cancer Relevance of Circulating Antibodies Against LINE-1 Antigens in Humans.

    Vylegzhanina, Alexandra V / Bespalov, Ivan A / Novototskaya-Vlasova, Ksenia A / Hall, Brandon M / Gleiberman, Anatoli S / Yu, Han / Leontieva, Olga V / Leonova, Katerina I / Kurnasov, Oleg V / Osterman, Andrei L / Dy, Grace K / Komissarov, Alexey A / Vasilieva, Elena / Gehlhausen, Jeff / Iwasaki, Akiko / Ambrosone, Christine B / Tsuji, Takemasa / Matsuzaki, Junko / Odunsi, Kunle /
    Andrianova, Ekaterina L / Gudkov, Andrei V

    Cancer research communications

    2023  Volume 3, Issue 11, Page(s) 2256–2267

    Abstract: Long interspersed nuclear element-1 (LINE-1 or L1), the most abundant family of autonomous retrotransposons occupying over 17% of human DNA, is epigenetically silenced in normal tissues by the mechanisms involving p53 but is frequently derepressed in ... ...

    Abstract Long interspersed nuclear element-1 (LINE-1 or L1), the most abundant family of autonomous retrotransposons occupying over 17% of human DNA, is epigenetically silenced in normal tissues by the mechanisms involving p53 but is frequently derepressed in cancer, suggesting that L1-encoded proteins may act as tumor-associated antigens recognized by the immune system. In this study, we established an immunoassay to detect circulating autoantibodies against L1 proteins in human blood. Using this assay in >2,800 individuals with or without cancer, we observed significantly higher IgG titers against L1-encoded ORF1p and ORF2p in patients with lung, pancreatic, ovarian, esophageal, and liver cancers than in healthy individuals. Remarkably, elevated levels of anti-ORF1p-reactive IgG were observed in patients with cancer with disease stages 1 and 2, indicating that the immune response to L1 antigens can occur in the early phases of carcinogenesis. We concluded that the antibody response against L1 antigens could contribute to the diagnosis and determination of immunoreactivity of tumors among cancer types that frequently escape early detection.
    Significance: The discovery of autoantibodies against antigens encoded by L1 retrotransposons in patients with five poorly curable cancer types has potential implications for the detection of an ongoing carcinogenic process and tumor immunoreactivity.
    MeSH term(s) Humans ; Retroelements ; Long Interspersed Nucleotide Elements/genetics ; Neoplasms/genetics ; Autoantibodies/genetics ; Immunoglobulin G/genetics
    Chemical Substances Retroelements ; Autoantibodies ; Immunoglobulin G
    Language English
    Publishing date 2023-10-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ISSN 2767-9764
    ISSN (online) 2767-9764
    DOI 10.1158/2767-9764.CRC-23-0289
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Structural and Biochemical Characterization of a Cold-Active PMGL3 Esterase with Unusual Oligomeric Structure.

    Boyko, Konstantin M / Kryukova, Mariya V / Petrovskaya, Lada E / Kryukova, Elena A / Nikolaeva, Alena Y / Korzhenevsky, Dmitry A / Lomakina, Galina Yu / Novototskaya-Vlasova, Ksenia A / Rivkina, Elizaveta M / Dolgikh, Dmitry A / Kirpichnikov, Mikhail P / Popov, Vladimir O

    Biomolecules

    2021  Volume 11, Issue 1

    Abstract: The gene coding for a novel cold-active esterase PMGL3 was previously obtained from a Siberian permafrost metagenomic DNA library and expressed ... ...

    Abstract The gene coding for a novel cold-active esterase PMGL3 was previously obtained from a Siberian permafrost metagenomic DNA library and expressed in
    MeSH term(s) Amino Acid Sequence ; Catalytic Domain ; Cold Temperature ; Detergents/pharmacology ; Enzyme Stability/drug effects ; Esterases/chemistry ; Esterases/metabolism ; Ions ; Metals/pharmacology ; Models, Molecular ; Mutagenesis, Site-Directed ; Mutant Proteins/chemistry ; Protein Multimerization ; Sodium Chloride/pharmacology ; Solvents ; Structural Homology, Protein
    Chemical Substances Detergents ; Ions ; Metals ; Mutant Proteins ; Solvents ; Sodium Chloride (451W47IQ8X) ; Esterases (EC 3.1.-)
    Language English
    Publishing date 2021-01-05
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2701262-1
    ISSN 2218-273X ; 2218-273X
    ISSN (online) 2218-273X
    ISSN 2218-273X
    DOI 10.3390/biom11010057
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Crystal structure of PMGL2 esterase from the hormone-sensitive lipase family with GCSAG motif around the catalytic serine.

    Boyko, Konstantin M / Kryukova, Marya V / Petrovskaya, Lada E / Nikolaeva, Alena Y / Korzhenevsky, Dmitry A / Novototskaya-Vlasova, Ksenia A / Rivkina, Elizaveta M / Dolgikh, Dmitry A / Kirpichnikov, Mikhail P / Popov, Vladimir O

    PloS one

    2020  Volume 15, Issue 1, Page(s) e0226838

    Abstract: Lipases comprise a large class of hydrolytic enzymes which catalyze the cleavage of the ester bonds in triacylglycerols and find numerous biotechnological applications. Previously, we have cloned the gene coding for a novel esterase PMGL2 from a Siberian ...

    Abstract Lipases comprise a large class of hydrolytic enzymes which catalyze the cleavage of the ester bonds in triacylglycerols and find numerous biotechnological applications. Previously, we have cloned the gene coding for a novel esterase PMGL2 from a Siberian permafrost metagenomic DNA library. We have determined the 3D structure of PMGL2 which belongs to the hormone-sensitive lipase (HSL) family and contains a new variant of the active site motif, GCSAG. Similar to many other HSLs, PMGL2 forms dimers in solution and in the crystal. Our results demonstrated that PMGL2 and structurally characterized members of the GTSAG motif subfamily possess a common dimerization interface that significantly differs from that of members of the GDSAG subfamily of known structure. Moreover, PMGL2 had a unique organization of the active site cavity with significantly different topology compared to the other lipolytic enzymes from the HSL family with known structure including the distinct orientation of the active site entrances within the dimer and about four times larger size of the active site cavity. To study the role of the cysteine residue in GCSAG motif of PMGL2, the catalytic properties and structure of its double C173T/C202S mutant were examined and found to be very similar to the wild type protein. The presence of the bound PEG molecule in the active site of the mutant form allowed for precise mapping of the amino acid residues forming the substrate cavity.
    MeSH term(s) Amino Acid Motifs ; Bacteria/chemistry ; Bacteria/enzymology ; Bacteria/genetics ; Bacterial Proteins/chemistry ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Catalytic Domain ; Crystallography, X-Ray ; Lipase/chemistry ; Lipase/genetics ; Lipase/metabolism ; Metagenome ; Models, Molecular ; Mutation ; Permafrost/microbiology ; Protein Conformation ; Protein Multimerization ; Serine/metabolism ; Siberia ; Substrate Specificity
    Chemical Substances Bacterial Proteins ; Serine (452VLY9402) ; Lipase (EC 3.1.1.3)
    Language English
    Publishing date 2020-01-28
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0226838
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Cloning, purification, and characterization of a cold-adapted esterase produced by Psychrobacter cryohalolentis K5T from Siberian cryopeg.

    Novototskaya-Vlasova, Ksenia / Petrovskaya, Lada / Yakimov, Sergey / Gilichinsky, David

    FEMS microbiology ecology

    2012  Volume 82, Issue 2, Page(s) 367–375

    Abstract: A psychrotrophic gram-negative bacterium Psychrobacter cryohalolentis K5(T) was previously isolated from a cryopeg within Siberian permafrost and its genome has been completely sequenced. To clone and characterize potential cold-active lipases/esterases ... ...

    Abstract A psychrotrophic gram-negative bacterium Psychrobacter cryohalolentis K5(T) was previously isolated from a cryopeg within Siberian permafrost and its genome has been completely sequenced. To clone and characterize potential cold-active lipases/esterases produced by P. cryohalolentis K5(T) , we have identified their potential genes by alignment with amino acid sequences of lipases/esterases from related bacteria. One of the targets, EstPc, was cloned and overexpressed in Escherichia coli BL21 (DE3) cells. The recombinant protein was produced with a 6x histidine tag at its C-terminus and purified by nickel affinity chromatography. Purified recombinant protein displayed maximum esterolytic activity with p-nitrophenyl butyrate (C4) as a substrate at 35 °C and pH 8.5. Activity assay conducted at different temperatures revealed that EstPc is a cold-adapted esterase which displayed more than 90% of its maximum activity at 0-5 °C. In contrast to many known cold-active enzymes, it possesses relatively high thermostability, preserving more than 60% of activity after incubation for 1 h at 80 °C. It was activated by Ca(2+) , Mn(2+) , and EDTA whereas Zn(+2) , Cu(+2) , Co(+2) , Ni(+2) , and Mg(+2) inhibited it. Various organic solvents (ethanol, methanol and others) inhibited the enzyme. Most non-ionic detergents, such as Triton X-100 and Tween 20 increased the lipase activity while SDS completely inhibited it.
    MeSH term(s) Amino Acid Sequence ; Cloning, Molecular ; Cold Temperature ; DNA, Bacterial/genetics ; Detergents/chemistry ; Enzyme Stability ; Escherichia coli/genetics ; Escherichia coli/metabolism ; Esterases/chemistry ; Esterases/genetics ; Hydrogen-Ion Concentration ; Metals/chemistry ; Molecular Sequence Data ; Octoxynol/chemistry ; Psychrobacter/enzymology ; Psychrobacter/genetics ; Recombinant Proteins/chemistry ; Recombinant Proteins/genetics ; Salinity ; Sequence Alignment ; Sequence Analysis, DNA ; Siberia ; Solvents/chemistry ; Substrate Specificity
    Chemical Substances DNA, Bacterial ; Detergents ; Metals ; Recombinant Proteins ; Solvents ; Octoxynol (9002-93-1) ; Esterases (EC 3.1.-)
    Language English
    Publishing date 2012-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 283722-5
    ISSN 1574-6941 ; 0168-6496
    ISSN (online) 1574-6941
    ISSN 0168-6496
    DOI 10.1111/j.1574-6941.2012.01385.x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Expression and chaperone-assisted refolding of a new cold-active lipase from Psychrobacter cryohalolentis K5ᵀ

    Novototskaya-Vlasova, Ksenia / Petrovskaya, Lada / Kryukova, Elena / Rivkina, Elizaveta / Dolgikh, Dmitry / Kirpichnikov, Mikhail

    Protein expression and purification. 2013 Sept., v. 91, no. 1

    2013  

    Abstract: We describe cloning and expression of genes coding for lipase Lip2Pc and lipase-specific foldase LifPc from a psychrotrophic microorganism Psychrobacter cryohalolentis K5ᵀ isolated from a Siberian cryopeg (the lense of overcooled brine within permafrost). ...

    Abstract We describe cloning and expression of genes coding for lipase Lip2Pc and lipase-specific foldase LifPc from a psychrotrophic microorganism Psychrobacter cryohalolentis K5ᵀ isolated from a Siberian cryopeg (the lense of overcooled brine within permafrost). Upon expression in Escherichiacoli Lip2Pc accumulated in inclusion bodies while chaperone was synthesized in a soluble form. An efficient protocol for solubilization and subsequent refolding of the recombinant lipase in the presence of the truncated chaperone was developed. Using this procedure Lip2Pc with specific activity of 6900U/mg was obtained. Contrary to published data on other lipase-chaperone complexes, refolded Lip2Pc was mostly recovered from the complex with chaperone by metal-affinity chromatography. Recombinant Lip2Pc displayed maximum lipolytic activity at 25°C and pH 8.0 with p-nitrophenyl palmitate (C16) as a substrate. Activity assays conducted at different temperatures revealed that the recombinant Lip2Pc is a cold-adapted lipase with ability to utilize substrates with long (C10–C16) hydrocarbon chains in the temperature range from +5 to +65°C. It demonstrated relatively high stability at temperatures above 60°C and in the presence of various metal ions or organic solvents (ethanol, methanol, etc.). Non-ionic detergents, such as Triton X-100 and Tween 20 decreased Lip2Pc activity and SDS completely inhibited it.
    Keywords Psychrobacter ; affinity chromatography ; detergents ; ethanol ; gene expression ; inclusion bodies ; lipolysis ; metal ions ; methanol ; octoxynol ; pH ; permafrost ; polysorbates ; solubilization ; solvents ; temperature
    Language English
    Dates of publication 2013-09
    Size p. 96-103.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 1055455-5
    ISSN 1096-0279 ; 1046-5928
    ISSN (online) 1096-0279
    ISSN 1046-5928
    DOI 10.1016/j.pep.2013.07.011
    Database NAL-Catalogue (AGRICOLA)

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  8. Article ; Online: New member of the hormone-sensitive lipase family from the permafrost microbial community.

    Petrovskaya, Lada E / Novototskaya-Vlasova, Ksenia A / Gapizov, Sultan Sh / Spirina, Elena V / Durdenko, Ekaterina V / Rivkina, Elizaveta M

    Bioengineered

    2016  Volume 8, Issue 4, Page(s) 420–423

    Abstract: Siberian permafrost is a unique environment inhabited with diverse groups of microorganisms. Among them, there are numerous producers of biotechnologically relevant enzymes including lipases and esterases. Recently, we have constructed a metagenomic ... ...

    Abstract Siberian permafrost is a unique environment inhabited with diverse groups of microorganisms. Among them, there are numerous producers of biotechnologically relevant enzymes including lipases and esterases. Recently, we have constructed a metagenomic library from a permafrost sample and identified in it several genes coding for potential lipolytic enzymes. In the current work, properties of the recombinant esterases obtained from this library are compared with the previously characterized lipase from Psychrobacter cryohalolentis and other representatives of the hormone-sensitive lipase family.
    MeSH term(s) Enzyme Activation ; Enzyme Stability ; Metagenome/genetics ; Microbial Consortia/physiology ; Permafrost/microbiology ; Siberia ; Sterol Esterase/chemistry ; Sterol Esterase/genetics
    Chemical Substances Sterol Esterase (EC 3.1.1.13)
    Language English
    Publishing date 2016-10-18
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2737830-5
    ISSN 2165-5987 ; 2165-5979
    ISSN (online) 2165-5987
    ISSN 2165-5979
    DOI 10.1080/21655979.2016.1230571
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Expression and chaperone-assisted refolding of a new cold-active lipase from Psychrobacter cryohalolentis K5(T).

    Novototskaya-Vlasova, Ksenia / Petrovskaya, Lada / Kryukova, Elena / Rivkina, Elizaveta / Dolgikh, Dmitry / Kirpichnikov, Mikhail

    Protein expression and purification

    2013  Volume 91, Issue 1, Page(s) 96–103

    Abstract: We describe cloning and expression of genes coding for lipase Lip2Pc and lipase-specific foldase LifPc from a psychrotrophic microorganism Psychrobacter cryohalolentis K5(T) isolated from a Siberian cryopeg (the lense of overcooled brine within ... ...

    Abstract We describe cloning and expression of genes coding for lipase Lip2Pc and lipase-specific foldase LifPc from a psychrotrophic microorganism Psychrobacter cryohalolentis K5(T) isolated from a Siberian cryopeg (the lense of overcooled brine within permafrost). Upon expression in Escherichiacoli Lip2Pc accumulated in inclusion bodies while chaperone was synthesized in a soluble form. An efficient protocol for solubilization and subsequent refolding of the recombinant lipase in the presence of the truncated chaperone was developed. Using this procedure Lip2Pc with specific activity of 6900U/mg was obtained. Contrary to published data on other lipase-chaperone complexes, refolded Lip2Pc was mostly recovered from the complex with chaperone by metal-affinity chromatography. Recombinant Lip2Pc displayed maximum lipolytic activity at 25°C and pH 8.0 with p-nitrophenyl palmitate (C16) as a substrate. Activity assays conducted at different temperatures revealed that the recombinant Lip2Pc is a cold-adapted lipase with ability to utilize substrates with long (C10-C16) hydrocarbon chains in the temperature range from +5 to +65°C. It demonstrated relatively high stability at temperatures above 60°C and in the presence of various metal ions or organic solvents (ethanol, methanol, etc.). Non-ionic detergents, such as Triton X-100 and Tween 20 decreased Lip2Pc activity and SDS completely inhibited it.
    MeSH term(s) Amino Acid Sequence ; Arctic Regions ; Enzyme Stability ; Escherichia coli/genetics ; Geologic Sediments/microbiology ; Lipase/biosynthesis ; Lipase/genetics ; Lipase/isolation & purification ; Lipase/metabolism ; Molecular Sequence Data ; Protein Refolding ; Psychrobacter/enzymology ; Psychrobacter/genetics ; Recombinant Proteins/chemistry ; Recombinant Proteins/genetics ; Recombinant Proteins/isolation & purification ; Recombinant Proteins/metabolism ; Sequence Alignment ; Substrate Specificity ; Temperature
    Chemical Substances Recombinant Proteins ; Lipase (EC 3.1.1.3) ; lipase foldase (EC 3.1.1.3)
    Language English
    Publishing date 2013-09
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1055455-5
    ISSN 1096-0279 ; 1046-5928
    ISSN (online) 1096-0279
    ISSN 1046-5928
    DOI 10.1016/j.pep.2013.07.011
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Expression and characterization of a new esterase with GCSAG motif from a permafrost metagenomic library

    Petrovskaya, Lada E / Novototskaya-Vlasova, Ksenia A / Spirina, Elena V / Durdenko, Ekaterina V / Lomakina, Galina Yu / Zavialova, Maria G / Nikolaev, Evgeny N / Rivkina, Elizaveta M

    FEMS microbiology ecology. 2016 May 01, v. 92, no. 5

    2016  

    Abstract: As a result of construction and screening of a metagenomic library prepared from a permafrost-derived microcosm, we have isolated a novel gene coding for a putative lipolytic enzyme that belongs to the hormone-sensitive lipase family. It encodes a ... ...

    Abstract As a result of construction and screening of a metagenomic library prepared from a permafrost-derived microcosm, we have isolated a novel gene coding for a putative lipolytic enzyme that belongs to the hormone-sensitive lipase family. It encodes a polypeptide of 343 amino acid residues whose amino acid sequence displays maximum likelihood with uncharacterized proteins from Sphingomonas species. A putative catalytic serine residue of PMGL2 resides in a new variant of a recently discovered GTSAG sequence in which a Thr residue is replaced by a Cys residue (GCSAG). The recombinant PMGL2 was produced in Escherichia coli cells and purified by Ni-affinity chromatography. The resulting protein preferably utilizes short-chain p-nitrophenyl esters (C4 and C8) and therefore is an esterase. It possesses maximum activity at 45°C in slightly alkaline conditions and has limited thermostability at higher temperatures. Activity of PMGL2 is stimulated in the presence of 0.25–1.5 M NaCl indicating the good salt tolerance of the new enzyme. Mass spectrometric analysis demonstrated that N-terminal methionine in PMGL2 is processed and cysteine residues do not form a disulfide bond. The results of the study demonstrate the significance of the permafrost environment as a unique genetic reservoir and its potential for metagenomic exploration.

    A gene coding for an esterase with GCSAG sequence motif around the catalytic serine residue was cloned from a permafrost metagenomic library.
    Keywords Escherichia coli ; Sphingomonas ; amino acid sequences ; carboxylic ester hydrolases ; catalytic activity ; chromatography ; cysteine ; disulfide bonds ; esters ; genes ; genomic libraries ; mass spectrometry ; metagenomics ; methionine ; permafrost ; polypeptides ; proteins ; salt tolerance ; screening ; serine ; sodium chloride ; statistical analysis ; temperature ; thermal stability
    Language English
    Dates of publication 2016-0501
    Publishing place Oxford University Press
    Document type Article
    ZDB-ID 283722-5
    ISSN 1574-6941 ; 0168-6496
    ISSN (online) 1574-6941
    ISSN 0168-6496
    DOI 10.1093/femsec/fiw046
    Database NAL-Catalogue (AGRICOLA)

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