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Sample records for gene product kerv

  1. Identification of genes and gene products necessary for bacterial bioluminescence.

    OpenAIRE

    Engebrecht, J; Silverman, M.

    1984-01-01

    Expression of luminescence in Escherichia coli was recently achieved by cloning genes from the marine bacterium Vibrio fischeri. One DNA fragment on a hybrid plasmid encoded regulatory functions and enzymatic activities necessary for light production. We report the results of a genetic analysis to identify the luminescence genes (lux) that reside on this recombinant plasmid. lux gene mutations were generated by hydroxylamine treatment, and these mutations were ordered on a linear map by compl...

  2. On the bursting of gene products

    CERN Document Server

    Yvinec, Romain

    2011-01-01

    In this article we demonstrate that the so-called bursting production of molecular species during gene expression may be an artifact caused by low time resolution in experimental data collection and not an actual burst in production. We reach this conclusion through an analysis of a two-stage and binary model for gene expression, and demonstrate that in the limit when mRNA degradation is much faster than protein degradation they are equivalent. The negative binomial distribution is shown to be a limiting case of the binary model for fast "on to off" state transitions and high values of the ratio between protein synthesis and degradation rates. The gene products population increases by unity but multiple times in a time interval orders of magnitude smaller than protein half-life or the precision of the experimental apparatus employed in its detection. This rare-and-fast one-by-one protein synthesis has been interpreted as bursting.

  3. [Immune response genes products in human physiology].

    Science.gov (United States)

    Khaitov, R M; Alekseev, L P

    2012-09-01

    Current data on physiological role of human immune response genes' proteomic products (antigens) are discussed. The antigens are specified by a very high level of diversity that mediates a wide specter ofphysiological functions. They actually provide integrity and biological stability of human as species. These data reveal new ideas on many pathological processes as well as drafts new approaches for prophylaxis and treatment.

  4. Combining Hierarchical and Associative Gene Ontology Relations with Textual Evidence in Estimating Gene and Gene Product Similarity

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Posse, Christian; Gopalan, Banu; Riensche, Roderick M.; Beagley, Nathaniel; Baddeley, Bob L.; Tratz, Stephen C.; Gregory, Michelle L.

    2007-03-01

    Gene and gene product similarity is a fundamental diagnostic measure in analyzing biological data and constructing predictive models for functional genomics. With the rising influence of the Gene Ontology, two complementary approaches have emerged where the similarity between two genes or gene products is obtained by comparing Gene Ontology (GO) annotations associated with the genes or gene products. One approach captures GO-based similarity in terms of hierarchical relations within each gene subontology. The other approach identifies GO-based similarity in terms of associative relations across the three gene subontologies. We propose a novel methodology where the two approaches can be merged with ensuing benefits in coverage and accuracy, and demonstrate that further improvements can be obtained by integrating textual evidence extracted from relevant biomedical literature.

  5. Correlating Information Contents of Gene Ontology Terms to Infer Semantic Similarity of Gene Products

    Directory of Open Access Journals (Sweden)

    Mingxin Gan

    2014-01-01

    Full Text Available Successful applications of the gene ontology to the inference of functional relationships between gene products in recent years have raised the need for computational methods to automatically calculate semantic similarity between gene products based on semantic similarity of gene ontology terms. Nevertheless, existing methods, though having been widely used in a variety of applications, may significantly overestimate semantic similarity between genes that are actually not functionally related, thereby yielding misleading results in applications. To overcome this limitation, we propose to represent a gene product as a vector that is composed of information contents of gene ontology terms annotated for the gene product, and we suggest calculating similarity between two gene products as the relatedness of their corresponding vectors using three measures: Pearson’s correlation coefficient, cosine similarity, and the Jaccard index. We focus on the biological process domain of the gene ontology and annotations of yeast proteins to study the effectiveness of the proposed measures. Results show that semantic similarity scores calculated using the proposed measures are more consistent with known biological knowledge than those derived using a list of existing methods, suggesting the effectiveness of our method in characterizing functional relationships between gene products.

  6. Correlating information contents of gene ontology terms to infer semantic similarity of gene products.

    Science.gov (United States)

    Gan, Mingxin

    2014-01-01

    Successful applications of the gene ontology to the inference of functional relationships between gene products in recent years have raised the need for computational methods to automatically calculate semantic similarity between gene products based on semantic similarity of gene ontology terms. Nevertheless, existing methods, though having been widely used in a variety of applications, may significantly overestimate semantic similarity between genes that are actually not functionally related, thereby yielding misleading results in applications. To overcome this limitation, we propose to represent a gene product as a vector that is composed of information contents of gene ontology terms annotated for the gene product, and we suggest calculating similarity between two gene products as the relatedness of their corresponding vectors using three measures: Pearson's correlation coefficient, cosine similarity, and the Jaccard index. We focus on the biological process domain of the gene ontology and annotations of yeast proteins to study the effectiveness of the proposed measures. Results show that semantic similarity scores calculated using the proposed measures are more consistent with known biological knowledge than those derived using a list of existing methods, suggesting the effectiveness of our method in characterizing functional relationships between gene products.

  7. Integrating Ontological Knowledge and Textual Evidence in Estimating Gene and Gene Product Similarity

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Posse, Christian; Gopalan, Banu; Tratz, Stephen C.; Gregory, Michelle L.

    2006-06-08

    With the rising influence of the Gene On-tology, new approaches have emerged where the similarity between genes or gene products is obtained by comparing Gene Ontology code annotations associ-ated with them. So far, these approaches have solely relied on the knowledge en-coded in the Gene Ontology and the gene annotations associated with the Gene On-tology database. The goal of this paper is to demonstrate that improvements to these approaches can be obtained by integrating textual evidence extracted from relevant biomedical literature.

  8. Deduced products of C4-dicarboxylate transport regulatory genes of Rhizobium leguminosarum are homologous to nitrogen regulatory gene products.

    OpenAIRE

    Ronson, C W; Astwood, P M; Nixon, B T; Ausubel, F M

    1987-01-01

    We have sequenced two genes dctB and dctD required for the activation of the C4-dicarboxylate transport structural gene dctA in free-living Rhizobium leguminosarum. The hydropathic profile of the dctB gene product (DctB) suggested that its N-terminal region may be located in the periplasm and its C-terminal region in the cytoplasm. The C-terminal region of DctB was strongly conserved with similar regions of the products of several regulatory genes that may act as environmental sensors, includ...

  9. Deduced products of C4-dicarboxylate transport regulatory genes of Rhizobium leguminosarum are homologous to nitrogen regulatory gene products.

    OpenAIRE

    Ronson, C W; Astwood, P M; Nixon, B T; Ausubel, F M

    1987-01-01

    We have sequenced two genes dctB and dctD required for the activation of the C4-dicarboxylate transport structural gene dctA in free-living Rhizobium leguminosarum. The hydropathic profile of the dctB gene product (DctB) suggested that its N-terminal region may be located in the periplasm and its C-terminal region in the cytoplasm. The C-terminal region of DctB was strongly conserved with similar regions of the products of several regulatory genes that may act as environmental sensors, includ...

  10. Enhanced citrate production through gene insertion in Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de; Nielsen, Jens

    2007-01-01

    The effect of inserting genes involved in the reductive branch of the tricarboxylic acid (TCA) cycle on citrate production by Aspergillus niger was evaluated. Several different genes were inserted individually and in combination, i.e. malate dehydrogenase (mdh2) from Saccharomyces cerevisiae, two...

  11. PRODUCT GENE REPRESENTATION AND ACQUISITION METHOD BASED ON POPULATION OF PRODUCT CASES

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The representation and acquisition of a product gene is a crucial problem in product evolutionary design. A new methodology of product gene representation and acquisition from a population of product cases is proposed, and the methodology for product evolutionary design based on a population of product cases is realized. By properly classifying product cases according to its product species, the populations of product cases are divided and a model is established. Knowledge of the scheme design is extracted and formulated as the function base, principle base, and structure base, which are then combined to form a product gene. Subsequently, the product gene tree is created and represented by object-oriented method. Then combining this method with the evolutionary reasoning technology, an intelligent and automatic evolutionary scheme design of product based on the population of product cases is realized. This design method will be helpful in the processing of knowledge formulation, accumulation, and reuse, and in addressing the difficulty of acquiring design knowledge in traditional design. In addition, the disadvantages of manual case adaptation and update in case-based reasoning can be eliminated. Moreover, by optimizing the design scheme in multiple levels and aspects of product function, principle, and structure etc., the level of creativity in the scheme design can be improved.

  12. A new gene ontology-based measure for the functional similarity of gene products

    Institute of Scientific and Technical Information of China (English)

    QI Guo-long; QIAN Shi-yu; FANG Ji-qian

    2013-01-01

    Background Although biomedical ontologies have standardized the representation of gene products across species and databases,a method for determining the functional similarities of gene products has not yet been developed.Methods We proposed a new semantic similarity measure based on Gene Ontology that considers the semantic influences from all of the ancestor terms in a graph.Our measure was compared with Resnik's measure in two applications,which were based on the association of the measure used with the gene co-expression and the proteinprotein interactions.Results The results showed a considerable association between the semantic similarity and the expression correlation and between the semantic similarity and the protein-protein interactions,and our measure performed the best overall.Conclusion These results revealed the potential value of our newly proposed semantic similarity measure in studying the functional relevance of gene products.

  13. Gene analogue finder: a GRID solution for finding functionally analogous gene products

    Directory of Open Access Journals (Sweden)

    Licciulli Flavio

    2007-09-01

    Full Text Available Abstract Background To date more than 2,1 million gene products from more than 100000 different species have been described specifying their function, the processes they are involved in and their cellular localization using a very well defined and structured vocabulary, the gene ontology (GO. Such vast, well defined knowledge opens the possibility of compare gene products at the level of functionality, finding gene products which have a similar function or are involved in similar biological processes without relying on the conventional sequence similarity approach. Comparisons within such a large space of knowledge are highly data and computing intensive. For this reason this project was based upon the use of the computational GRID, a technology offering large computing and storage resources. Results We have developed a tool, GENe AnaloGue FINdEr (ENGINE that parallelizes the search process and distributes the calculation and data over the computational GRID, splitting the process into many sub-processes and joining the calculation and the data on the same machine and therefore completing the whole search in about 3 days instead of occupying one single machine for more than 5 CPU years. The results of the functional comparison contain potential functional analogues for more than 79000 gene products from the most important species. 46% of the analyzed gene products are well enough described for such an analysis to individuate functional analogues, such as well-known members of the same gene family, or gene products with similar functions which would never have been associated by standard methods. Conclusion ENGINE has produced a list of potential functionally analogous relations between gene products within and between species using, in place of the sequence, the gene description of the GO, thus demonstrating the potential of the GO. However, the current limiting factor is the quality of the associations of many gene products from non

  14. A two-cassette reporter system for assessing target gene translation and target gene product inclusion body formation

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a dual cassette reporter system capable of assessing target gene translation and target gene product folding. The present invention further relates to vectors and host cells comprising the dual cassette reporter system. In addition the invention relates to the use...... of the dual cassette reporter system for assessing target gene translation and target gene product folding....

  15. Perinatal Gene-Gene and Gene-Environment Interactions on IgE Production and Asthma Development

    Directory of Open Access Journals (Sweden)

    Jen-Chieh Chang

    2012-01-01

    Full Text Available Atopic asthma is a complex disease associated with IgE-mediated immune reactions. Numerous genome-wide studies identified more than 100 genes in 22 chromosomes associated with atopic asthma, and different genetic backgrounds in different environments could modulate susceptibility to atopic asthma. Current knowledge emphasizes the effect of tobacco smoke on the development of childhood asthma. This suggests that asthma, although heritable, is significantly affected by gene-gene and gene-environment interactions. Evidence has recently shown that molecular mechanism of a complex disease may be limited to not only DNA sequence differences, but also gene-environmental interactions for epigenetic difference. This paper reviews and summarizes how gene-gene and gene-environment interactions affect IgE production and the development of atopic asthma in prenatal and childhood stages. Based on the mechanisms responsible for perinatal gene-environment interactions on IgE production and development of asthma, we formulate several potential strategies to prevent the development of asthma in the perinatal stage.

  16. Natural Products Version 2.0: Connecting Genes to Molecules

    Science.gov (United States)

    Walsh, Christopher T.; Fischbach, Michael A.

    2009-01-01

    Natural products have played a prominent role in the history of organic chemistry, and they continue to be important as drugs, biological probes, and targets of study for synthetic and analytical chemists. In this perspective, we explore how connecting Nature’s small molecules to the genes that encode them has sparked a renaissance in natural product research, focusing primarily on the biosynthesis of polyketides and nonribosomal peptides. We survey monomer biogenesis, coupling chemistries from templated and non-templated pathways, and the broad set of tailoring reactions and hybrid pathways that give rise to the diverse scaffolds and functionalization patterns of natural products. We conclude by considering two questions: What would it take to find all natural product scaffolds? What kind of scientists will be studying natural products in the future? PMID:20121095

  17. Use of Galerina marginata genes and proteins for peptide production

    Energy Technology Data Exchange (ETDEWEB)

    Hallen-Adams, Heather E.; Scott-Craig, John S.; Walton, Jonathan D.; Luo, Hong

    2016-03-01

    The present invention relates to compositions and methods comprising genes and peptides associated with cyclic peptides and cyclic peptide production in mushrooms. In particular, the present invention relates to using genes and proteins from Galerina species encoding peptides specifically relating to amatoxins in addition to proteins involved with processing cyclic peptide toxins. In a preferred embodiment, the present invention also relates to methods for making small peptides and small cyclic peptides including peptides similar to amanitin. Further, the present inventions relate to providing kits for making small peptides.

  18. Use of Galerina marginata genes and proteins for peptide production

    Energy Technology Data Exchange (ETDEWEB)

    Hallen-Adams, Heather E.; Scott-Craig, John S.; Walton, Jonathan D.; Luo, Hong

    2017-03-21

    The present invention relates to compositions and methods comprising genes and peptides associated with cyclic peptides and cyclic peptide production in mushrooms. In particular, the present invention relates to using genes and proteins from Galerina species encoding peptides specifically relating to amatoxins in addition to proteins involved with processing cyclic peptide toxins. In a preferred embodiment, the present invention also relates to methods for making small peptides and small cyclic peptides including peptides similar to amanitin. Further, the present inventions relate to providing kits for making small peptides.

  19. Use of Galerina marginata genes and proteins for peptide production

    Science.gov (United States)

    Hallen-Adams, Heather E.; Scott-Craig, John S.; Walton, Jonathan D.; Luo, Hong

    2016-03-01

    The present invention relates to compositions and methods comprising genes and peptides associated with cyclic peptides and cyclic peptide production in mushrooms. In particular, the present invention relates to using genes and proteins from Galerina species encoding peptides specifically relating to amatoxins in addition to proteins involved with processing cyclic peptide toxins. In a preferred embodiment, the present invention also relates to methods for making small peptides and small cyclic peptides including peptides similar to amanitin. Further, the present inventions relate to providing kits for making small peptides.

  20. Id-1 gene and gene products as therapeutic targets for treatment of breast cancer and other types of carcinoma

    Science.gov (United States)

    Desprez, Pierre-Yves; Campisi, Judith

    2014-08-19

    A method for treatment of breast cancer and other types of cancer. The method comprises targeting and modulating Id-1 gene expression, if any, for the Id-1 gene, or gene products in breast or other epithelial cancers in a patient by delivering products that modulate Id-1 gene expression. When expressed, Id-1 gene is a prognostic indicator that cancer cells are invasive and metastatic.

  1. Identification of Drosophila Gene Products Required for Phagocytosis of Candidaalbicans.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available Phagocytosis is a highly conserved aspect of innate immunity. We used Drosophila melanogaster S2 cells as a model system to study the phagocytosis of Candida albicans, the major fungal pathogen of humans, by screening an RNAi library representing 7,216 fly genes conserved among metazoans. After rescreening the initial genes identified and eliminating certain classes of housekeeping genes, we identified 184 genes required for efficient phagocytosis of C. albicans. Diverse biological processes are represented, with actin cytoskeleton regulation, vesicle transport, signaling, and transcriptional regulation being prominent. Secondary screens using Escherichia coli and latex beads revealed several genes specific for C. albicans phagocytosis. Characterization of one of those gene products, Macroglobulin complement related (Mcr, shows that it is secreted, that it binds specifically to the surface of C. albicans, and that it promotes its subsequent phagocytosis. Mcr is closely related to the four Drosophila thioester proteins (Teps, and we show that TepII is required for efficient phagocytosis of E. coli (but not C. albicans or Staphylococcus aureus and that TepIII is required for the efficient phagocytosis of S. aureus (but not C. albicans or E. coli. Thus, this family of fly proteins distinguishes different pathogens for subsequent phagocytosis.

  2. Plasmid genes required for microcin B17 production.

    Science.gov (United States)

    San Millán, J L; Kolter, R; Moreno, F

    1985-09-01

    The production of the antibiotic substance microcin B17 (Mcc) is determined by a 3.5-kilobase DNA fragment from plasmid pMccB17. Several Mcc- mutations on plasmid pMccB17 were obtained by both transposon insertion and nitrosoguanidine mutagenesis. Plasmids carrying these mutations were tested for their ability to complement Mcc- insertion or deletion mutations on pMM102 (pMM102 is a pBR322 derivative carrying the region encoding microcin B17). Results from these experiments indicate that at least four plasmid genes are required for microcin production.

  3. Natural product proteomining, a quantitative proteomics platform, allows rapid discovery of biosynthetic gene clusters for different classes of natural products.

    Science.gov (United States)

    Gubbens, Jacob; Zhu, Hua; Girard, Geneviève; Song, Lijiang; Florea, Bogdan I; Aston, Philip; Ichinose, Koji; Filippov, Dmitri V; Choi, Young H; Overkleeft, Herman S; Challis, Gregory L; van Wezel, Gilles P

    2014-06-19

    Information on gene clusters for natural product biosynthesis is accumulating rapidly because of the current boom of available genome sequencing data. However, linking a natural product to a specific gene cluster remains challenging. Here, we present a widely applicable strategy for the identification of gene clusters for specific natural products, which we name natural product proteomining. The method is based on using fluctuating growth conditions that ensure differential biosynthesis of the bioactivity of interest. Subsequent combination of metabolomics and quantitative proteomics establishes correlations between abundance of natural products and concomitant changes in the protein pool, which allows identification of the relevant biosynthetic gene cluster. We used this approach to elucidate gene clusters for different natural products in Bacillus and Streptomyces, including a novel juglomycin-type antibiotic. Natural product proteomining does not require prior knowledge of the gene cluster or secondary metabolite and therefore represents a general strategy for identification of all types of gene clusters.

  4. Metabolic engineering of Arabidopsis for butanetriol production using bacterial genes.

    Science.gov (United States)

    Abdel-Ghany, Salah E; Day, Irene; Heuberger, Adam L; Broeckling, Corey D; Reddy, Anireddy S N

    2013-11-01

    1,2,4-butanetriol (butanetriol) is a useful precursor for the synthesis of the energetic material butanetriol trinitrate and several pharmaceutical compounds. Bacterial synthesis of butanetriol from xylose or arabinose takes place in a pathway that requires four enzymes. To produce butanetriol in plants by expressing bacterial enzymes, we cloned native bacterial or codon optimized synthetic genes under different promoters into a binary vector and stably transformed Arabidopsis plants. Transgenic lines expressing introduced genes were analyzed for the production of butanetriol using gas chromatography coupled to mass spectrometry (GC-MS). Soil-grown transgenic plants expressing these genes produced up to 20 µg/g of butanetriol. To test if an exogenous supply of pentose sugar precursors would enhance the butanetriol level, transgenic plants were grown in a medium supplemented with either xylose or arabinose and the amount of butanetriol was quantified. Plants expressing synthetic genes in the arabinose pathway showed up to a forty-fold increase in butanetriol levels after arabinose was added to the medium. Transgenic plants expressing either bacterial or synthetic xylose pathways, or the arabinose pathway showed toxicity symptoms when xylose or arabinose was added to the medium, suggesting that a by-product in the pathway or butanetriol affected plant growth. Furthermore, the metabolite profile of plants expressing arabinose and xylose pathways was altered. Our results demonstrate that bacterial pathways that produce butanetriol can be engineered into plants to produce this chemical. This proof-of-concept study for phytoproduction of butanetriol paves the way to further manipulate metabolic pathways in plants to enhance the level of butanetriol production.

  5. Involvement of distinct PKC gene products in T cell functions

    Directory of Open Access Journals (Sweden)

    Gottfried eBaier

    2012-08-01

    Full Text Available It is well established that members of the Protein kinase C(PKC family seem to have important roles in T cells. Focusing on the physiological and non-redundant PKC functions established in primary mouse T cells via germline gene-targeting approaches, our current knowledge defines two particularly critical PKC gene products, PKCθ and PKCα, as the flavor of PKC in T cells that appear to have a positive role in signaling pathways that are necessary for full antigen receptor-mediated T cell activation ex vivo and T cell-mediated immunity in vivo. Consistently, in spite of the current dogma that PKCθ inhibition might be sufficient to achieve complete immunosuppressive effects, more recent results have indicated that the pharmacological inhibition of PKCθ, and additionally, at least PKCα, appears to be needed to provide a successful approach for the prevention of allograft rejection and treatment of autoimmune diseases.

  6. Alphavirus vectors: applications for DNA vaccine production and gene expression.

    Science.gov (United States)

    Lundstrom, K

    2000-01-01

    Replication-deficient alphavirus vectors have been developed for efficient high-level transgene expression. The broad host range of alphaviruses has allowed infection of a wide variety of mammalian cell lines and primary cultures. Particularly, G protein-coupled receptors have been expressed at high levels and subjected to binding and functional studies. Expression in suspension cultures has greatly facilitated production of large quantities of recombinant proteins for structural studies. Injection of recombinant alphavirus vectors into rodent brain resulted in local reporter gene expression. Highly neuron-specific expression was obtained in hippocampal slice cultures in vivo. Additionally, preliminary studies in animal models suggest that alphavirus vectors can be attractive candidates for gene therapy applications. Traditionally alphavirus vectors, either attenuated strains or replication-deficient particles, have been used to elicit efficient immune responses in animals. Recently, the application of alphaviruses has been extended to naked nucleic acids. Injection of DNA as well as RNA vectors has demonstrated efficient antigen production. In many cases, protection against lethal challenges has been obtained after immunization with alphavirus particles or nucleic acid vectors. Alphavirus vectors can therefore be considered as potentially promising vectors for vaccine production.

  7. Single gene insertion drives bioalcohol production by a thermophilic archaeon

    Energy Technology Data Exchange (ETDEWEB)

    Basen, M; Schut, GJ; Nguyen, DM; Lipscomb, GL; Benn, RA; Prybol, CJ; Vaccaro, BJ; Poole, FL; Kelly, RM; Adams, MWW

    2014-12-09

    Bioethanol production is achieved by only two metabolic pathways and only at moderate temperatures. Herein a fundamentally different synthetic pathway for bioalcohol production at 70 degrees C was constructed by insertion of the gene for bacterial alcohol dehydrogenase (AdhA) into the archaeon Pyrococcus furiosus. The engineered strain converted glucose to ethanol via acetate and acetaldehyde, catalyzed by the host-encoded aldehyde ferredoxin oxidoreductase (AOR) and heterologously expressed AdhA, in an energy-conserving, redox-balanced pathway. Furthermore, the AOR/AdhA pathway also converted exogenously added aliphatic and aromatic carboxylic acids to the corresponding alcohol using glucose, pyruvate, and/or hydrogen as the source of reductant. By heterologous coexpression of a membrane-bound carbon monoxide dehydrogenase, CO was used as a reductant for converting carboxylic acids to alcohols. Redirecting the fermentative metabolism of P. furiosus through strategic insertion of foreign genes creates unprecedented opportunities for thermophilic bioalcohol production. Moreover, the AOR/AdhA pathway is a potentially game-changing strategy for syngas fermentation, especially in combination with carbon chain elongation pathways.

  8. 76 FR 9028 - Guidance for Industry: Potency Tests for Cellular and Gene Therapy Products; Availability

    Science.gov (United States)

    2011-02-16

    ... Industry: Potency Tests for Cellular and Gene Therapy Products'' dated January 2011. The guidance document provides manufacturers of cellular and gene therapy (CGT) products with recommendations for developing... document entitled ``Guidance for Industry: Potency Tests for Cellular and Gene Therapy Products''...

  9. Vitreoscilla hemoglobin gene ( vgb) improves lutein production in Chlorella vulgaris

    Science.gov (United States)

    Ma, Ruijuan; Lin, Xiangzhi

    2014-03-01

    Vitreoscilla hemoglobin is an oxygen-binding protein that promotes oxygen delivery and reduces oxygen consumption under low oxygen conditions to increase the efficiency of cell respiration and metabolism. In this study, we introduced a Vitreoscilla hemoglobin gene ( vgb) into Chlorella vulgaris by Agrobacterium tumefaciens -mediated transformation (ATMT). PCR analysis confirmed that the vgb gene was successfully integrated into the Chlorella vulgaris genome. Analysis of biomass obtained in shake flasks revealed transformant biomass concentrations as high as 3.28 g/L, which was 38.81% higher than that of the wild-type strain. Lutein content of transformants also increased slightly. Further experiments recovered a maximum lutein yield of 2.91 mg/L from the transformants, which was 36.77% higher than that of the wild-type strain. The above results suggest that integrated expression of the vgb gene may improve cell growth and lutein yield in Chlorella vulgaris, with applications to lutein production from Chlorella during fermentation.

  10. Genes related to xylose fermentation and methods of using same for enhanced biofuel production

    Science.gov (United States)

    Wohlbach, Dana J.; Gasch, Audrey P.

    2014-08-05

    The present invention provides isolated gene sequences involved in xylose fermentation and related recombinant yeast which are useful in methods of enhanced biofuel production, particularly ethanol production. Methods of bioengineering recombinant yeast useful for biofuel production are also provided.

  11. Genes related to xylose fermentation and methods of using same for enhanced biofuel production

    Energy Technology Data Exchange (ETDEWEB)

    Wohlbach, Dana J.; Gasch, Audrey P.

    2016-11-29

    The present invention provides isolated gene sequences involved in xylose fermentation and related recombinant yeast which are useful in methods of enhanced biofuel production, particularly ethanol production. Methods of bioengineering recombinant yeast useful for biofuel production are also provided.

  12. Identifying the Interaction between Genes and Gene Products Based on Frequently Seen Verbs in Medline Abstracts.

    Science.gov (United States)

    Sekimizu; Park; Tsujii

    1998-01-01

    We have selected the most frequently seen verbs from raw texts made up of 1-million-words of Medline abstracts, and we were able to identify (or bracket) noun phrases contained in the corpus, with a precision rate of 90%. Then, based on the noun-phrase-bracketted corpus, we tried to find the subject and object terms for some frequently seen verbs in the domain. The precision rate of finding the right subject and object for each verb was about 73%. This task was only made possible because we were able to linguistically analyze (or parse) a large quantity of a raw corpus. Our approach will be useful for classifying genes and gene products and for identifying the interaction between them. It is the first step of our effort in building a genome-related thesaurus and hierarchies in a fully automatic way.

  13. Identification of the dnaA and dnaN gene products of Escherichia coli.

    Science.gov (United States)

    Yuasa, S; Sakakibara, Y

    1980-01-01

    A specialized transducing lambda phage carrying the dnaN genes of Escherichia coli specifies two proteins of about 41 and 48 kilodaltons (kd). The temperature-sensitive mutations, dnaN59 and dnaA167, were found to result in altered isoelectric points of the 41 and 48 kd proteins, respectively. Thus the dnaN gene product was identified as a weakly acidic 41 and 48 kd protein. The synthesis of the dnaN gene product is greatly reduced by insertion of a transposon Tn3 in the dnaA gene and by deletion in the gene at the distal end to the dnaN gene. Temperature-sensitive dnaA mutations, on the dnaN gene product. These results indicate that the synthesis of the dnaN gene product is dependent on the structural integrity of the dnaA gene.

  14. Expression regulation of design process gene in product design

    DEFF Research Database (Denmark)

    Fang, Lusheng; Li, Bo; Tong, Shurong

    2011-01-01

    is proposed and analyzed, as well as its three categories i.e., the operator gene, the structural gene and the regulator gene. Second, the trigger mechanism that design objectives and constraints trigger the operator gene is constructed. Third, the expression principle of structural gene is analyzed......To improve the design process efficiency, this paper proposes the principle and methodology that design process gene controls the characteristics of design process under the framework of design process reuse and optimization based on design process gene. First, the concept of design process gene...... with the example of design management gene. Last, the regulation mode that the regulator gene regulates the expression of the structural gene is established and it is illustrated by taking the design process management gene as an example. © (2011) Trans Tech Publications....

  15. Gene Delivery into Plant Cells for Recombinant Protein Production

    Directory of Open Access Journals (Sweden)

    Qiang Chen

    2015-01-01

    Full Text Available Recombinant proteins are primarily produced from cultures of mammalian, insect, and bacteria cells. In recent years, the development of deconstructed virus-based vectors has allowed plants to become a viable platform for recombinant protein production, with advantages in versatility, speed, cost, scalability, and safety over the current production paradigms. In this paper, we review the recent progress in the methodology of agroinfiltration, a solution to overcome the challenge of transgene delivery into plant cells for large-scale manufacturing of recombinant proteins. General gene delivery methodologies in plants are first summarized, followed by extensive discussion on the application and scalability of each agroinfiltration method. New development of a spray-based agroinfiltration and its application on field-grown plants is highlighted. The discussion of agroinfiltration vectors focuses on their applications for producing complex and heteromultimeric proteins and is updated with the development of bridge vectors. Progress on agroinfiltration in Nicotiana and non-Nicotiana plant hosts is subsequently showcased in context of their applications for producing high-value human biologics and low-cost and high-volume industrial enzymes. These new advancements in agroinfiltration greatly enhance the robustness and scalability of transgene delivery in plants, facilitating the adoption of plant transient expression systems for manufacturing recombinant proteins with a broad range of applications.

  16. Association of cGH EcoRV Gene with Production in Tolaki Chicken

    Directory of Open Access Journals (Sweden)

    Muhammad Amrullah Pagala

    2017-02-01

    Full Text Available cGH (Chicken Growth Hormone gene plays a crucial role in production responses of chicken. The objective of the research was to investigate the association of cGH gene with production in Tolaki chicken. Tolaki chicken is native chickens from Southeast Sulawesi Province of Indonesian. cGH gene was genotyped in 58 Tolaki chicken with PCR-RFLP. PCR was used to amplify genomic DNA for GH gene (399 bp. The amplicon was cutted by EcoRV and produced three genotypes: AA, AG, and GG and two alleles: A and G allele. The study showed the association of GH gene polymorphism with Production traits. GG genotype have better production (daily weight gain and feed conversion than AG genotype in Tolaki chicken, providing evidence that GH gene might be an important candidate gene for production traits.

  17. Extended gene expression by medium exchange and repeated transient transfection for recombinant protein production enhancement.

    Science.gov (United States)

    Cervera, Laura; Gutiérrez-Granados, Sonia; Berrow, Nicholas Simon; Segura, Maria Mercedes; Gòdia, Francesc

    2015-05-01

    Production of recombinant products in mammalian cell cultures can be achieved by stable gene expression (SGE) or transient gene expression (TGE). The former is based on the integration of a plasmid DNA into the host cell genome allowing continuous gene expression. The latter is based on episomal plasmid DNA expression. Conventional TGE is limited to a short production period of usually about 96 h, therefore limiting productivity. A novel gene expression approach termed extended gene expression (EGE) is explored in this study. The aim of EGE is to prolong the production period by the combination of medium exchange and repeated transfection of cell cultures with plasmid DNA to improve overall protein production. The benefit of this methodology was evaluated for the production of three model recombinant products: intracellular GFP, secreted GFP, and a Gag-GFP virus-like particles (VLPs). Productions were carried out in HEK 293 cell suspension cultures grown in animal-derived component free media using polyethylenimine (PEI) as transfection reagent. Transfections were repeated throughout the production process using different plasmid DNA concentrations, intervals of time, and culture feeding conditions in order to identify the best approach to achieve sustained high-level gene expression. Using this novel EGE strategy, the production period was prolonged between 192 and 240 h with a 4-12-fold increase in production levels, depending on the product type considered. © 2014 Wiley Periodicals, Inc.

  18. [Collaborative study on regulatory science for facilitating clinical development of gene therapy products for genetic diseases].

    Science.gov (United States)

    Uchida, Eriko; Igarashi, Yuka; Sato, Yoji

    2014-01-01

    Gene therapy products are expected as innovative medicinal products for intractable diseases such as life-threatening genetic diseases and cancer. Recently, clinical developments by pharmaceutical companies are accelerated in Europe and the United States, and the first gene therapy product in advanced countries was approved for marketing authorization by the European Commission in 2012. On the other hand, more than 40 clinical studies for gene therapy have been completed or ongoing in Japan, most of them are conducted as clinical researches by academic institutes, and few clinical trials have been conducted for approval of gene therapy products. In order to promote the development of gene therapy products, revision of the current guideline and/or preparation of concept paper to address the evaluation of the quality and safety of gene therapy products are necessary and desired to clearly show what data should be submitted before First-in-Human clinical trials of novel gene therapy products. We started collaborative study with academia and regulatory agency to promote regulatory science toward clinical development of gene therapy products for genetic diseases based on lentivirus and adeno-associated virus vectors; National Center for Child Health and Development (NCCHD), Nippon Medical School and PMDA have been joined in the task force. At first, we are preparing pre-draft of the revision of the current gene therapy guidelines in this project.

  19. Requirements for Clinical Trials with Gene Therapy and Transplant Products in Switzerland.

    Science.gov (United States)

    Marti, Andreas

    2015-01-01

    This chapter aims to describe and summarize the regulation of gene and cell therapy products in Switzerland and its legal basis. Product types are briefly described, as are Swiss-specific terminologies such as the term "transplant product," which means products manufactured from cells, tissues, or even whole organs. Although some parts of this chapter may show a guideline character, they are not legally binding, but represent the current thinking of Swissmedic, the Swiss Agency for Therapeutic Products. As so far the experience with marketing approval of gene therapy and cell therapy products in Switzerland is limited, this chapter focuses on the regulation of clinical trials conducted with these products. Quality, nonclinical, and clinical aspects are summarized separately for gene therapy products and transplant products.

  20. Form gene clustering method about pan-ethnic-group products based on emotional semantic

    Science.gov (United States)

    Chen, Dengkai; Ding, Jingjing; Gao, Minzhuo; Ma, Danping; Liu, Donghui

    2016-09-01

    The use of pan-ethnic-group products form knowledge primarily depends on a designer's subjective experience without user participation. The majority of studies primarily focus on the detection of the perceptual demands of consumers from the target product category. A pan-ethnic-group products form gene clustering method based on emotional semantic is constructed. Consumers' perceptual images of the pan-ethnic-group products are obtained by means of product form gene extraction and coding and computer aided product form clustering technology. A case of form gene clustering about the typical pan-ethnic-group products is investigated which indicates that the method is feasible. This paper opens up a new direction for the future development of product form design which improves the agility of product design process in the era of Industry 4.0.

  1. Identification of alcA, a Bordetella bronchiseptica gene necessary for alcaligin production.

    Science.gov (United States)

    Giardina, P C; Foster, L A; Toth, S I; Roe, B A; Dyer, D W

    1995-12-29

    The alcA gene, essential for the production of the dihydroxamate siderophore, alcaligin, by Bordetella bronchiseptica, was cloned and sequenced. The alcA gene was identified on a 4.7-kb EcoRI genomic fragment adjacent to a Tn5lac transposon insertion that inactivated alcaligin production in strain MBORD846. Analysis of the alcA nucleotide sequence revealed a putative Fur-binding site, suggesting that expression of this gene is repressed by iron. The deduced amino-acid sequence of this open reading frame had significant homology with the Escherichia coli iucD gene product, an enzyme required for biosynthesis of the dihydroxamate siderophore aerobactin.

  2. Long-term follow-up of cancer patients treated with gene therapy medicinal products.

    Science.gov (United States)

    Galli, Maria Cristina

    2012-06-01

    European Union requirements are discussed for the long-term follow-up of advanced therapy medicinal products, as well as how they can be applied to cancer patients treated with gene therapy medicinal products in the context of clinical trials, as described in a specific guideline issued by Gene Therapy Working Party at the European Medicine Agency.

  3. Aflatoxin conducive and non-conducive growth conditions reveal new gene associations with aflatoxin production.

    Science.gov (United States)

    Price, Michael S; Conners, Shannon B; Tachdjian, Sabrina; Kelly, Robert M; Payne, Gary A

    2005-06-01

    Research on aflatoxin (AF) production has traditionally focused on defining the AF biosynthetic pathway with the goal of identifying potential targets for intervention. To understand the effect of nitrogen source, carbon source, temperature, and pH on the regulation of AF biosynthesis, a targeted cDNA microarray consisting of genes associated with AF production over time was employed. Expression profiles for genes involved in AF biosynthesis grouped into five clades. A putative regulon was identified consisting of 20 genes that were induced in the conducive nitrogen and pH treatments and the non-conducive carbon and temperature treatments, as well as four other putative regulons corresponding to each of the four variables studied. Seventeen genes exhibited consistent induction/repression profiles across all the experiments. One of these genes was consistently downregulated with AF production. Overexpression of this gene resulted in repression of AF biosynthesis. The cellular function of this gene is currently unresolved.

  4. FSim: A Novel Functional Similarity Search Algorithm and Tool for Discovering Functionally Related Gene Products

    Directory of Open Access Journals (Sweden)

    Qiang Hu

    2014-01-01

    Full Text Available Background. During the analysis of genomics data, it is often required to quantify the functional similarity of genes and their products based on the annotation information from gene ontology (GO with hierarchical structure. A flexible and user-friendly way to estimate the functional similarity of genes utilizing GO annotation is therefore highly desired. Results. We proposed a novel algorithm using a level coefficient-weighted model to measure the functional similarity of gene products based on multiple ontologies of hierarchical GO annotations. The performance of our algorithm was evaluated and found to be superior to the other tested methods. We implemented the proposed algorithm in a software package, FSim, based on R statistical and computing environment. It can be used to discover functionally related genes for a given gene, group of genes, or set of function terms. Conclusions. FSim is a flexible tool to analyze functional gene groups based on the GO annotation databases.

  5. Reciprocal Regulation of Pyoluteorin Production with Membrane Transporter Gene Expression in Pseudomonas fluorescens Pf-5

    OpenAIRE

    2005-01-01

    Pyoluteorin is a chlorinated polyketide antibiotic secreted by the rhizosphere bacterium Pseudomonas fluorescens Pf-5. Genes encoding enzymes and transcriptional regulators involved in pyoluteorin production are clustered in the genome of Pf-5. Sequence analysis of genes adjacent to the known pyoluteorin biosynthetic gene cluster revealed the presence of an ABC transporter system. We disrupted two putative ABC transporter genes by inserting transcriptional fusions to an ice nucleation reporte...

  6. Identification of potentially hazardous human gene products in GMO risk assessment.

    Science.gov (United States)

    Bergmans, Hans; Logie, Colin; Van Maanen, Kees; Hermsen, Harm; Meredyth, Michelle; Van Der Vlugt, Cécile

    2008-01-01

    Genetically modified organisms (GMOs), e.g. viral vectors, could threaten the environment if by their release they spread hazardous gene products. Even in contained use, to prevent adverse consequences, viral vectors carrying genes from mammals or humans should be especially scrutinized as to whether gene products that they synthesize could be hazardous in their new context. Examples of such potentially hazardous gene products (PHGPs) are: protein toxins, products of dominant alleles that have a role in hereditary diseases, gene products and sequences involved in genome rearrangements, gene products involved in immunomodulation or with an endocrine function, gene products involved in apoptosis, activated proto-oncogenes. For contained use of a GMO that carries a construct encoding a PHGP, the precautionary principle dictates that safety measures should be applied on a "worst case" basis, until the risks of the specific case have been assessed. The potential hazard of cloned genes can be estimated before empirical data on the actual GMO become available. Preliminary data may be used to focus hazard identification and risk assessment. Both predictive and empirical data may also help to identify what further information is needed to assess the risk of the GMO. A two-step approach, whereby a PHGP is evaluated for its conceptual dangers, then checked by data bank searches, is delineated here.

  7. Weaver gene 3'UTR novel mutations: Associations with production ...

    African Journals Online (AJOL)

    use

    2011-11-21

    Nov 21, 2011 ... Key words: Dairy goat, weaver gene, milk performance traits, single nucleotide polymorphism. INTRODUCTION ... Cattle weaver syndrome is related to cattle milk ..... Moreover, this study contributed to its evaluation as genetic ...

  8. Prolactin as a Candidate Gene Controlling Molting and Egg Production of Duck

    Directory of Open Access Journals (Sweden)

    Triana Susanti

    2015-03-01

    Full Text Available Incidence of molting is a crucial problem in the local ducks that need to be handled from many aspects including genetic aspect. Handling of molting genetically can be done quickly and accurately when the control genes have been found. The search for marker genes of molting can be conducted in poultry through broodiness naturally, because its physiological processes are related to the continuity of egg production. This paper describes the mechanism of molting, the relationship of molting with prolactin hormone and the association of prolactin gene polymorphism with molting and egg production. Molting and egg production were influenced by the prolactin hormone, that may be controlled by the prolactin gene. High concentration of prolactin hormone will inhibit the function of pituitary gland, decreasing production of gonadotrophin hormone (follicle stimulating hormone and luteinizing hormone hence ovulation ceased. This will stop egg production and at the same time molting proccess occurred.

  9. Product-induced gene expression, a product-responsive reporter assay used to screen metagenomic libraries for enzyme-encoding genes.

    Science.gov (United States)

    Uchiyama, Taku; Miyazaki, Kentaro

    2010-11-01

    A reporter assay-based screening method for enzymes, which we named product-induced gene expression (PIGEX), was developed and used to screen a metagenomic library for amidases. A benzoate-responsive transcriptional activator, BenR, was placed upstream of the gene encoding green fluorescent protein and used as a sensor. Escherichia coli sensor cells carrying the benR-gfp gene cassette fluoresced in response to benzoate concentrations as low as 10 μM but were completely unresponsive to the substrate benzamide. An E. coli metagenomic library consisting of 96,000 clones was grown in 96-well format in LB medium containing benzamide. The library cells were then cocultivated with sensor cells. Eleven amidase genes were recovered from 143 fluorescent wells; eight of these genes were homologous to known bacterial amidase genes while three were novel genes. In addition to their activity toward benzamide, the enzymes were active toward various substrates, including d- and l-amino acid amides, and displayed enantioselectivity. Thus, we demonstrated that PIGEX is an effective approach for screening novel enzymes based on product detection.

  10. Cell surface expression system for the display of heterologous gene products using chimeric flagellin fusions of bacillus halodurans isolate

    CSIR Research Space (South Africa)

    Du Plessis, A

    2006-10-01

    Full Text Available N-terminal sequencing gave rise to homology to flagellin protein, product of the hag gene. protein, product of the hag gene. Gene was cloned by using degenerate primers and inverse PCR. The gene sequence as well as the up- and down- stream regions...

  11. DNA sequence, products, and transcriptional pattern of the genes involved in production of the DNA replication inhibitor microcin B17.

    Science.gov (United States)

    Genilloud, O; Moreno, F; Kolter, R

    1989-02-01

    The 3.8-kilobase segment of plasmid DNA that contains the genes required for production of the DNA replication inhibitor microcin B17 was sequenced. The sequence contains four open reading frames which were shown to be translated in vivo by the construction of fusions to lacZ. The location of these open reading frames fits well with the location of the four microcin B17 production genes, mcbABCD, identified previously through genetic complementation. The products of the four genes have been identified, and the observed molecular weights of the proteins agree with those predicted from the nucleotide sequence. The transcription of these genes was studied by using fusions to lacZ and physical mapping of mRNA start sites. Three promoters were identified in this region. The major promoter for all the genes is a growth phase-regulated OmpR-dependent promoter located upstream of mcbA. A second promoter is located within mcbC and is responsible for a low-level basal expression of mcbD. A third promoter, located within mcbD, promotes transcription in the reverse direction starting within mcbD and extending through mcbC. The resulting mRNA appears to be an untranslated antisense transcript that could play a regulatory role in the expression of these genes.

  12. Sites and gene products involved in lambdoid phage DNA packaging.

    Science.gov (United States)

    Smith, M P; Feiss, M

    1993-04-01

    21 is a temperate lambdoid coliphage, and the genes that encode the head proteins of lambda and 21 are descended from a common ancestral bacteriophage. The sequencing of terminase genes 1 and 2 of 21 was completed, along with that of a segment at the right end of 21 DNA that includes the R4 sequence. The R4 sequence, a site that is likely involved in termination of DNA packaging, was found to be very similar to the R4 sequences of lambda and phi 80, suggesting that R4 is a recognition site that is not phage specific. DNA packaging by 21 is dependent on a host protein, integration host factor. A series of mutations in gene 1 (her mutations), which allow integration host factor-independent DNA packaging by 21, were found to be missense changes that affect predicted alpha-helixes in gp1. gp2, the large terminase subunit, is predicted to contain an ATP-binding domain and, perhaps, a second domain important for the cos-cutting activity of terminase. orf1, an open reading frame analogous in position to FI, a lambda gene involved in DNA packaging, shares some sequence identity with FI. orf1 was inactivated with nonsense and insertion mutations; these mutations were found not to affect phage growth. 21 was also not able to complement a lambda FI mutant.

  13. Inducible amplification of gene copy number and heterologous protein production in the yeast Kluyveromyces lactis.

    Science.gov (United States)

    Morlino, G B; Tizzani, L; Fleer, R; Frontali, L; Bianchi, M M

    1999-11-01

    Heterologous protein production can be doubled by increasing the copy number of the corresponding heterologous gene. We constructed a host-vector system in the yeast Kluyveromyces lactis that was able to induce copy number amplification of pKD1 plasmid-based vectors upon expression of an integrated copy of the plasmid recombinase gene. We increased the production and secretion of two heterologous proteins, glucoamylase from the yeast Arxula adeninivorans and mammalian interleukin-1beta, following gene dosage amplification when the heterologous genes were carried by pKD1-based vectors. The choice of the promoters for expression of the integrated recombinase gene and of the episomal heterologous genes are critical for the mitotic stability of the host-vector system.

  14. Improvement of gougerotin and nikkomycin production by engineering their biosynthetic gene clusters.

    Science.gov (United States)

    Du, Deyao; Zhu, Yu; Wei, Junhong; Tian, Yuqing; Niu, Guoqing; Tan, Huarong

    2013-07-01

    Nikkomycins and gougerotin are peptidyl nucleoside antibiotics with broad biological activities. The nikkomycin biosynthetic gene cluster comprises one pathway-specific regulatory gene (sanG) and 21 structural genes, whereas the gene cluster for gougerotin biosynthesis includes one putative regulatory gene, one major facilitator superfamily transporter gene, and 13 structural genes. In the present study, we introduced sanG driven by six different promoters into Streptomyces ansochromogenes TH322. Nikkomycin production was increased significantly with the highest increase in engineered strain harboring hrdB promoter-driven sanG. In the meantime, we replaced the native promoter of key structural genes in the gougerotin (gou) gene cluster with the hrdB promoters. The heterologous producer Streptomyces coelicolor M1146 harboring the modified gene cluster produced gougerotin up to 10-fold more than strains carrying the unmodified cluster. Therefore, genetic manipulations of genes involved in antibiotics biosynthesis with the constitutive hrdB promoter present a robust, easy-to-use system generally useful for the improvement of antibiotics production in Streptomyces.

  15. Gene delivery into plant cells for recombinant protein production

    National Research Council Canada - National Science Library

    Chen, Qiang; Lai, Huafang

    2015-01-01

    .... In recent years, the development of deconstructed virus-based vectors has allowed plants to become a viable platform for recombinant protein production, with advantages in versatility, speed, cost...

  16. Gene Delivery into Plant Cells for Recombinant Protein Production

    OpenAIRE

    Qiang Chen; Huafang Lai

    2015-01-01

    Recombinant proteins are primarily produced from cultures of mammalian, insect, and bacteria cells. In recent years, the development of deconstructed virus-based vectors has allowed plants to become a viable platform for recombinant protein production, with advantages in versatility, speed, cost, scalability, and safety over the current production paradigms. In this paper, we review the recent progress in the methodology of agroinfiltration, a solution to overcome the challenge of transgene d...

  17. Mobile antibiotic resistance - the spread of genes determining the resistance of bacteria through food products.

    Science.gov (United States)

    Godziszewska, Jolanta; Guzek, Dominika; Głąbski, Krzysztof; Wierzbicka, Agnieszka

    2016-07-07

    In recent years, more and more antibiotics have become ineffective in the treatment of bacterial nfections. The acquisition of antibiotic resistance by bacteria is associated with circulation of genes in the environment. Determinants of antibiotic resistance may be transferred to pathogenic bacteria. It has been shown that conjugation is one of the key mechanisms responsible for spread of antibiotic resistance genes, which is highly efficient and allows the barrier to restrictions and modifications to be avoided. Some conjugative modules enable the transfer of plasmids even between phylogenetically distant bacterial species. Many scientific reports indicate that food is one of the main reservoirs of these genes. Antibiotic resistance genes have been identified in meat products, milk, fruits and vegetables. The reason for such a wide spread of antibiotic resistance genes is the overuse of antibiotics by breeders of plants and animals, as well as by horizontal gene transfer. It was shown, that resistance determinants located on mobile genetic elements, which are isolated from food products, can easily be transferred to another niche. The antibiotic resistance genes have been in the environment for 30 000 years. Their removal from food products is not possible, but the risks associated with the emergence of multiresistant pathogenic strains are very large. The only option is to control the emergence, selection and spread of these genes. Therefore measures are sought to prevent horizontal transfer of genes. Promising concepts involve the combination of developmental biology, evolution and ecology in the fight against the spread of antibiotic resistance.

  18. Antibacterial Discovery and Development: From Gene to Product and Back

    Directory of Open Access Journals (Sweden)

    Victor Fedorenko

    2015-01-01

    Full Text Available Concern over the reports of antibiotic-resistant bacterial infections in hospitals and in the community has been publicized in the media, accompanied by comments on the risk that we may soon run out of antibiotics as a way to control infectious disease. Infections caused by Enterococcus faecium, Staphylococcus aureus, Klebsiella species, Clostridium difficile, Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, and other Enterobacteriaceae species represent a major public health burden. Despite the pharmaceutical sector’s lack of interest in the topic in the last decade, microbial natural products continue to represent one of the most interesting sources for discovering and developing novel antibacterials. Research in microbial natural product screening and development is currently benefiting from progress that has been made in other related fields (microbial ecology, analytical chemistry, genomics, molecular biology, and synthetic biology. In this paper, we review how novel and classical approaches can be integrated in the current processes for microbial product screening, fermentation, and strain improvement.

  19. Antibacterial Discovery and Development: From Gene to Product and Back

    Science.gov (United States)

    Fedorenko, Victor; Genilloud, Olga; Horbal, Liliya; Marcone, Giorgia Letizia; Marinelli, Flavia; Paitan, Yossi; Ron, Eliora Z.

    2015-01-01

    Concern over the reports of antibiotic-resistant bacterial infections in hospitals and in the community has been publicized in the media, accompanied by comments on the risk that we may soon run out of antibiotics as a way to control infectious disease. Infections caused by Enterococcus faecium, Staphylococcus aureus, Klebsiella species, Clostridium difficile, Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, and other Enterobacteriaceae species represent a major public health burden. Despite the pharmaceutical sector's lack of interest in the topic in the last decade, microbial natural products continue to represent one of the most interesting sources for discovering and developing novel antibacterials. Research in microbial natural product screening and development is currently benefiting from progress that has been made in other related fields (microbial ecology, analytical chemistry, genomics, molecular biology, and synthetic biology). In this paper, we review how novel and classical approaches can be integrated in the current processes for microbial product screening, fermentation, and strain improvement. PMID:26339625

  20. Production of cloned pigs with targeted attenuation of gene expression.

    Directory of Open Access Journals (Sweden)

    Vilceu Bordignon

    Full Text Available The objective of this study was to demonstrate that RNA interference (RNAi and somatic cell nuclear transfer (SCNT technologies can be used to attenuate the expression of specific genes in tissues of swine, a large animal species. Apolipoprotein E (apoE, a secreted glycoprotein known for its major role in lipid and lipoprotein metabolism and transport, was selected as the target gene for this study. Three synthetic small interfering RNAs (siRNA targeting the porcine apoE mRNA were tested in porcine granulosa cells in primary culture and reduced apoE mRNA abundance ranging from 45-82% compared to control cells. The most effective sequence was selected for cloning into a short hairpin RNA (shRNA expression vector under the control of RNA polymerase III (U6 promoter. Stably transfected fetal porcine fibroblast cells were generated and used to produce embryos with in vitro matured porcine oocytes, which were then transferred into the uterus of surrogate gilts. Seven live and one stillborn piglet were born from three gilts that became pregnant. Integration of the shRNA expression vector into the genome of clone piglets was confirmed by PCR and expression of the GFP transgene linked to the expression vector. Analysis showed that apoE protein levels in the liver and plasma of the clone pigs bearing the shRNA expression vector targeting the apoE mRNA was significantly reduced compared to control pigs cloned from non-transfected fibroblasts of the same cell line. These results demonstrate the feasibility of applying RNAi and SCNT technologies for introducing stable genetic modifications in somatic cells for eventual attenuation of gene expression in vivo in large animal species.

  1. Nonlinear biosynthetic gene cluster dose effect on penicillin production by Penicillium chrysogenum.

    Science.gov (United States)

    Nijland, Jeroen G; Ebbendorf, Bjorg; Woszczynska, Marta; Boer, Rémon; Bovenberg, Roel A L; Driessen, Arnold J M

    2010-11-01

    Industrial penicillin production levels by the filamentous fungus Penicillium chrysogenum increased dramatically by classical strain improvement. High-yielding strains contain multiple copies of the penicillin biosynthetic gene cluster that encodes three key enzymes of the β-lactam biosynthetic pathway. We have analyzed the gene cluster dose effect on penicillin production using the high-yielding P. chrysogenum strain DS17690 that was cured from its native clusters. The amount of penicillin V produced increased with the penicillin biosynthetic gene cluster number but was saturated at high copy numbers. Likewise, transcript levels of the biosynthetic genes pcbAB [δ-(l-α-aminoadipyl)-l-cysteinyl-d-valine synthetase], pcbC (isopenicillin N synthase), and penDE (acyltransferase) correlated with the cluster copy number. Remarkably, the protein level of acyltransferase, which localizes to peroxisomes, was saturated already at low cluster copy numbers. At higher copy numbers, intracellular levels of isopenicillin N increased, suggesting that the acyltransferase reaction presents a limiting step at a high gene dose. Since the number and appearance of the peroxisomes did not change significantly with the gene cluster copy number, we conclude that the acyltransferase activity is limiting for penicillin biosynthesis at high biosynthetic gene cluster copy numbers. These results suggest that at a high penicillin production level, productivity is limited by the peroxisomal acyltransferase import activity and/or the availability of coenzyme A (CoA)-activated side chains.

  2. Id-1 and Id-2 genes and products as markers of epithelial cancer

    Energy Technology Data Exchange (ETDEWEB)

    Desprez, Pierre-Yves (El Cerrito, CA); Campisi, Judith (Berkeley, CA)

    2011-10-04

    A method for detection and prognosis of breast cancer and other types of cancer. The method comprises detecting expression, if any, for both an Id-1 and an Id-2 genes, or the ratio thereof, of gene products in samples of breast tissue obtained from a patient. When expressed, Id-1 gene is a prognostic indicator that breast cancer cells are invasive and metastatic, whereas Id-2 gene is a prognostic indicator that breast cancer cells are localized and noninvasive in the breast tissue.

  3. Id-1 and Id-2 genes and products as markers of epithelial cancer

    Science.gov (United States)

    Desprez, Pierre-Yves [El Cerrito, CA; Campisi, Judith [Berkeley, CA

    2011-10-04

    A method for detection and prognosis of breast cancer and other types of cancer. The method comprises detecting expression, if any, for both an Id-1 and an Id-2 genes, or the ratio thereof, of gene products in samples of breast tissue obtained from a patient. When expressed, Id-1 gene is a prognostic indicator that breast cancer cells are invasive and metastatic, whereas Id-2 gene is a prognostic indicator that breast cancer cells are localized and noninvasive in the breast tissue.

  4. Id-1 and Id-2 genes and products as markers of epithelial cancer

    Science.gov (United States)

    Desprez, Pierre-Yves; Campisi, Judith

    2008-09-30

    A method for detection and prognosis of breast cancer and other types of cancer. The method comprises detecting expression, if any, for both an Id-1 and an Id-2 genes, or the ratio thereof, of gene products in samples of breast tissue obtained from a patient. When expressed, Id-1 gene is a prognostic indicator that breast cancer cells are invasive and metastatic, whereas Id-2 gene is a prognostic indicator that breast cancer cells are localized and noninvasive in the breast tissue.

  5. Major genes and QTL influencing wool production and quality: a review

    Directory of Open Access Journals (Sweden)

    Purvis Ian

    2005-12-01

    Full Text Available Abstract The opportunity exists to utilise our knowledge of major genes that influence the economically important traits in wool sheep. Genes with Mendelian inheritance have been identified for many important traits in wool sheep. Of particular importance are genes influencing pigmentation, wool quality and the keratin proteins, the latter of which are important for the morphology of the wool fibre. Gene mapping studies have identified some chromosomal regions associated with variation in wool quality and production traits. The challenge now is to build on this knowledge base in a cost-effective way to deliver molecular tools that facilitate enhanced genetic improvement programs for wool sheep.

  6. Regulation of gene expression by tobacco product preparations in cultured human dermal fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Malpass, Gloria E., E-mail: gloria.malpass@gmail.com [Department of Physiology and Pharmacology, Wake Forest University Health Sciences, Winston-Salem, NC 27157 (United States); Arimilli, Subhashini, E-mail: sarimill@wakehealth.edu [Department of Microbiology and Immunology, Wake Forest University Health Sciences, Winston-Salem, NC 27157 (United States); Prasad, G.L., E-mail: prasadg@rjrt.com [R and D Department, R.J. Reynolds Tobacco Company, Winston-Salem, NC 27102 (United States); Howlett, Allyn C., E-mail: ahowlett@wakehealth.edu [Department of Physiology and Pharmacology, Wake Forest University Health Sciences, Winston-Salem, NC 27157 (United States)

    2014-09-01

    Skin fibroblasts comprise the first barrier of defense against wounds, and tobacco products directly contact the oral cavity. Cultured human dermal fibroblasts were exposed to smokeless tobacco extract (STE), total particulate matter (TPM) from tobacco smoke, or nicotine at concentrations comparable to those found in these extracts for 1 h or 5 h. Differences were identified in pathway-specific genes between treatments and vehicle using qRT-PCR. At 1 h, IL1α was suppressed significantly by TPM and less significantly by STE. Neither FOS nor JUN was suppressed at 1 h by tobacco products. IL8, TNFα, VCAM1, and NFκB1 were suppressed after 5 h with STE, whereas only TNFα and NFκB1 were suppressed by TPM. At 1 h with TPM, secreted levels of IL10 and TNFα were increased. Potentially confounding effects of nicotine were exemplified by genes such as ATF3 (5 h), which was increased by nicotine but suppressed by other components of STE. Within 2 h, TPM stimulated nitric oxide production, and both STE and TPM increased reactive oxygen species. The biological significance of these findings and utilization of the gene expression changes reported herein regarding effects of the tobacco product preparations on dermal fibroblasts will require additional research. - Highlights: • Tobacco product preparations (TPPs) alter gene expression in dermal fibroblasts. • Some immediate early genes critical to the inflammatory process are affected. • Different TPPs produce differential responses in certain pro-inflammatory genes.

  7. Gene deletion of cytosolic ATP: citrate lyase leads to altered organic acid production in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; Nielsen, Michael Lynge; Olsson, Lisbeth

    2009-01-01

    With the availability of the genome sequence of the filamentous fungus Aspergillus niger, the use of targeted genetic modifications has become feasible. This, together with the fact that A. niger is well established industrially, makes this fungus an attractive micro-organism for creating a cell...... factory platform for production of chemicals. Using molecular biology techniques, this study focused on metabolic engineering of A. niger to manipulate its organic acid production in the direction of succinic acid. The gene target for complete gene deletion was cytosolic ATP: citrate lyase (acl), which...... the acl gene. Additionally, the total amount of organic acids produced in the deletion strain was significantly increased. Genome-scale stoichiometric metabolic model predictions can be used for identifying gene targets. Deletion of the acl led to increased succinic acid production by A. niger....

  8. Identification and manipulation of the pleuromutilin gene cluster from Clitopilus passeckerianus for increased rapid antibiotic production

    Science.gov (United States)

    Bailey, Andy M.; Alberti, Fabrizio; Kilaru, Sreedhar; Collins, Catherine M.; de Mattos-Shipley, Kate; Hartley, Amanda J.; Hayes, Patrick; Griffin, Alison; Lazarus, Colin M.; Cox, Russell J.; Willis, Christine L.; O’Dwyer, Karen; Spence, David W.; Foster, Gary D.

    2016-05-01

    Semi-synthetic derivatives of the tricyclic diterpene antibiotic pleuromutilin from the basidiomycete Clitopilus passeckerianus are important in combatting bacterial infections in human and veterinary medicine. These compounds belong to the only new class of antibiotics for human applications, with novel mode of action and lack of cross-resistance, representing a class with great potential. Basidiomycete fungi, being dikaryotic, are not generally amenable to strain improvement. We report identification of the seven-gene pleuromutilin gene cluster and verify that using various targeted approaches aimed at increasing antibiotic production in C. passeckerianus, no improvement in yield was achieved. The seven-gene pleuromutilin cluster was reconstructed within Aspergillus oryzae giving production of pleuromutilin in an ascomycete, with a significant increase (2106%) in production. This is the first gene cluster from a basidiomycete to be successfully expressed in an ascomycete, and paves the way for the exploitation of a metabolically rich but traditionally overlooked group of fungi.

  9. Identification and distribution of products from novel tryptopyrokinin genes in the locust, Locusta migratoria.

    Science.gov (United States)

    Redeker, Jana; Bläser, Marcel; Neupert, Susanne; Predel, Reinhard

    2017-04-22

    A recent analysis of the genome of Locusta migratoria indicated the presence of four novel insect neuropeptide genes encoding for multiple tryptopyrokinin peptides (tryptoPKs); hitherto only known from pyrokinin or capa genes. In our study, mature products of tryptoPK genes 1 and 2 were identified by mass spectrometry; precursor sequences assigned to the tryptoPK genes 3 and 4 are likely partial sequences of a single precursor. The expression of tryptoPK genes 1 and 2 is restricted to two cells in the subesophageal ganglion, exhibiting not only a unique neuropeptidome but also a very distinctive axonal projection. Comparative neuroendocrinology revealed that homologous cells in other insects also produce tryptoPKs but use other genes to generate this pattern. Since capa and pyrokinin genes are discussed as ancestors of the tryptoPK genes, we completed the hitherto only partially known precursor sequences of these genes by means of transcriptome analyses. The distribution of mature products of CAPA and pyrokinin precursors in the CNS is compared with that of tryptoPKs. In addition, a novel pyrokinin-like precursor is described.

  10. Utility of the pat gene as a selectable marker gene in production of transgenic Dunaliella salina

    Directory of Open Access Journals (Sweden)

    Hyo Sun Jung

    2016-09-01

    Full Text Available Abstract Background The objective of this study was to develop an efficient selectable marker for transgenic Dunaliella salina. Results Tests of the sensitivity of D. salina to the antibiotic chloramphenicol and the herbicide Basta® showed that cells (1.0 × 106 cells/ml treated with 1000 or 1500 μg/ml chloramphenicol died in 8 or 6 days, respectively, whereas D. salina cells (1.0 × 106 cells/ml treated with 5, 10, 20, or 40 μg/ml Basta® died in 2 days. Therefore, D. salina is more sensitive to Basta® than to chloramphenicol. To examine the possibility of using the phosphinothricin N-acetyltransferase (pat gene as a selectable marker gene, we introduced the pat genes into D. salina with particle bombardment system under the condition of helium pressure of 900 psi from a distance of 3 cm. PCR analysis confirmed that the gene was stably inserted into the cells and that the cells survived in 5 μg/ml Basta®, the medium used to select the transformed cells. Conclusions The findings of this study suggest that the pat gene can be used as an efficient selectable marker when producing transgenic D. salina.

  11. The paf gene product modulates asexual development in Penicillium chrysogenum.

    Science.gov (United States)

    Hegedüs, Nikoletta; Sigl, Claudia; Zadra, Ivo; Pócsi, Istvan; Marx, Florentine

    2011-06-01

    Penicillium chrysogenum secretes a low molecular weight, cationic and cysteine-rich protein (PAF). It has growth inhibitory activity against the model organism Aspergillus nidulans and numerous zoo- and phytopathogenic fungi but shows only minimal conditional antifungal activity against the producing organism itself. In this study we provide evidence for an additional function of PAF which is distinct from the antifungal activity against putative ecologically concurrent microorganisms. Our data indicate that PAF enhances conidiation in P. chrysogenum by modulating the expression of brlA, the central regulatory gene for mitospore development. A paf deletion strain showed a significant impairment of mitospore formation which sustains our hypothesis that PAF plays an important role in balancing asexual differentiation in P. chrysogenum.

  12. Alphavirus vectors for vaccine production and gene therapy.

    Science.gov (United States)

    Lundstrom, Kenneth

    2003-06-01

    Alphavirus vectors demonstrate high expression of heterologous proteins in a broad range of host cells. Replication-deficient as well as replication-competent variants exist. Systemic delivery of many viral antigens has elicited strong antibody responses in immunized mice and primates, and protection against challenges with lethal viruses was obtained. Similarly, prophylactic vaccination was established against tumor challenges. Attention has been paid to the engineering of improved targeting to immunologically active cells, such as dendritic cells. In the area of gene therapy, intratumoral injections of alphavirus vectors have resulted in potentially promising tumor rejection. Moreover, encapsulation of alphavirus particles into liposomes demonstrated efficient tumor targeting in mice with severe combined immunodeficiency, which permitted the initiation of clinical trials for patients with advanced kidney carcinoma and melanoma.

  13. Systems Pharmacology‐Based Discovery of Natural Products for Precision Oncology Through Targeting Cancer Mutated Genes

    Science.gov (United States)

    Fang, J; Cai, C; Wang, Q; Lin, P

    2017-01-01

    Massive cancer genomics data have facilitated the rapid revolution of a novel oncology drug discovery paradigm through targeting clinically relevant driver genes or mutations for the development of precision oncology. Natural products with polypharmacological profiles have been demonstrated as promising agents for the development of novel cancer therapies. In this study, we developed an integrated systems pharmacology framework that facilitated identifying potential natural products that target mutated genes across 15 cancer types or subtypes in the realm of precision medicine. High performance was achieved for our systems pharmacology framework. In case studies, we computationally identified novel anticancer indications for several US Food and Drug Administration‐approved or clinically investigational natural products (e.g., resveratrol, quercetin, genistein, and fisetin) through targeting significantly mutated genes in multiple cancer types. In summary, this study provides a powerful tool for the development of molecularly targeted cancer therapies through targeting the clinically actionable alterations by exploiting the systems pharmacology of natural products. PMID:28294568

  14. Regulation of a novel gene cluster involved in secondary metabolite production in Streptomyces coelicolor.

    Science.gov (United States)

    Hindra; Pak, Patricia; Elliot, Marie A

    2010-10-01

    Antibiotic biosynthesis in the streptomycetes is a complex and highly regulated process. Here, we provide evidence for the contribution of a novel genetic locus to antibiotic production in Streptomyces coelicolor. The overexpression of a gene cluster comprising four protein-encoding genes (abeABCD) and an antisense RNA-encoding gene (α-abeA) stimulated the production of the blue-pigmented metabolite actinorhodin on solid medium. Actinorhodin production also was enhanced by the overexpression of an adjacent gene (abeR) encoding a predicted Streptomyces antibiotic regulatory protein (SARP), while the deletion of this gene impaired actinorhodin production. We found the abe genes to be differentially regulated and controlled at multiple levels. Upstream of abeA was a promoter that directed the transcription of abeABCD at a low but constitutive level. The expression of abeBCD was, however, significantly upregulated at a time that coincided with the initiation of aerial development and the onset of secondary metabolism; this expression was activated by the binding of AbeR to four heptameric repeats upstream of a promoter within abeA. Expressed divergently to the abeBCD promoter was α-abeA, whose expression mirrored that of abeBCD but did not require activation by AbeR. Instead, α-abeA transcript levels were subject to negative control by the double-strand-specific RNase, RNase III.

  15. Physiological evaluation of the filamentous fungus Trichoderma reesei in production processes by marker gene expression analysis

    Directory of Open Access Journals (Sweden)

    Penttilä Merja

    2007-05-01

    Full Text Available Abstract Background Biologically relevant molecular markers can be used in evaluation of the physiological state of an organism in biotechnical processes. We monitored at high frequency the expression of 34 marker genes in batch, fed-batch and continuous cultures of the filamentous fungus Trichoderma reesei by the transcriptional analysis method TRAC (TRanscript analysis with the aid of Affinity Capture. Expression of specific genes was normalised either with respect to biomass or to overall polyA RNA concentration. Expressional variation of the genes involved in various process relevant cellular functions, such as protein production, growth and stress responses, was related to process parameters such as specific growth and production rates and substrate and dissolved oxygen concentrations. Results Gene expression of secreted cellulases and recombinant Melanocarpus albomyces laccase predicted the trends in the corresponding extracellular enzyme production rates and was highest in a narrow "physiological window" in the specific growth rate (μ range of 0.03 – 0.05 h-1. Expression of ribosomal protein mRNAs was consistent with the changes in μ. Nine starvation-related genes were found as potential markers for detection of insufficient substrate feed for maintaining optimal protein production. For two genes induced in anaerobic conditions, increasing transcript levels were measured as dissolved oxygen decreased. Conclusion The data obtained by TRAC supported the usefulness of focused and intensive transcriptional analysis in monitoring of biotechnical processes providing thus tools for process optimisation purposes.

  16. Reciprocal regulation of pyoluteorin production with membrane transporter gene expression in Pseudomonas fluorescens Pf-5.

    Science.gov (United States)

    Brodhagen, Marion; Paulsen, Ian; Loper, Joyce E

    2005-11-01

    Pyoluteorin is a chlorinated polyketide antibiotic secreted by the rhizosphere bacterium Pseudomonas fluorescens Pf-5. Genes encoding enzymes and transcriptional regulators involved in pyoluteorin production are clustered in the genome of Pf-5. Sequence analysis of genes adjacent to the known pyoluteorin biosynthetic gene cluster revealed the presence of an ABC transporter system. We disrupted two putative ABC transporter genes by inserting transcriptional fusions to an ice nucleation reporter gene. Mutations in pltI and pltJ, which are predicted to encode a membrane fusion protein and an ATP-binding cassette of the ABC transporter, respectively, greatly reduced pyoluteorin production by Pf-5. During the transition from exponential growth to stationary phase, populations of a pltI mutant were lower than those of a pltI+ strain in a culture medium containing pyoluteorin, suggesting a role for the transport system in efflux and the resistance of Pf-5 to the antibiotic. Although pltI or pltJ mutant strains displayed low pyoluteorin production, they did not accumulate proportionately more of the antibiotic intracellularly, indicating that pltI and pltJ do not encode an exclusive exporter for pyoluteorin. Transcription of the putative pyoluteorin efflux genes pltI and pltJ was enhanced by exogenous pyoluteorin. These new observations parallel an earlier finding that pyoluteorin enhances the transcription of pyoluteorin biosynthesis genes and pyoluteorin production in Pf-5. This report provides evidence of a coordination of pyoluteorin production and the transcription of genes encoding a linked transport apparatus, wherein each requires the other for optimal expression.

  17. Cloning large natural product gene clusters from the environment: Piecing environmental DNA gene clusters back together with TAR

    OpenAIRE

    Kim, Jeffrey H.; Feng, Zhiyang; Bauer, John D.; Kallifidas, Dimitris; Calle, Paula Y.; Brady, Sean F

    2010-01-01

    A single gram of soil can contain thousands of unique bacterial species, of which only a small fraction is regularly cultured in the laboratory. Although the fermentation of cultured microorganisms has provided access to numerous bioactive secondary metabolites, with these same methods it is not possible to characterize the natural products encoded by the uncultured majority. The heterologous expression of biosynthetic gene clusters cloned from DNA extracted directly from environmental sample...

  18. Genes, language, cognition, and culture: towards productive inquiry.

    Science.gov (United States)

    Fitch, W Tecumseh

    2011-04-01

    The Queen Mary conference on “Integrating Genetic and Cultural Evolutionary Approaches to Language,” and the papers in this special issue, clearly illustrate the excitement and potential of trans-disciplinary approaches to language as an evolved biological capacity (phylogeny) and an evolving cultural entity (glossogeny). Excepting the present author, the presenters/authors are mostly young rising stars in their respective fields, and include scientists with backgrounds in linguistics, animal communication, neuroscience, evolutionary biology, anthropology, and computer science. On display was a clear willingness to engage with different approaches and terminology and a commitment to shared standards of scientific rigor, empirically driven theory, and logical argument. Because the papers assembled here, together with the introduction, speak for themselves, I will focus in this “extro-duction” on some of the terminological and conceptual difficulties which threaten to block this exciting wave of scientific progress in understanding language evolution, in both senses of that term. In particular I will first argue against the regrettably widespread practice of opposing cultural and genetic explanations of human cognition as if they were dichotomous. Second, I will unpack the debate concerning “general-purpose” and “domain-specific” mechanisms, which masquerades as a debate about nativism but is nothing of the sort. I believe that framing discussions of language in these terms has generated more heat than light, and that a modern molecular understanding of genes, development, behavior, and evolution renders many of the assumptions underlying this debate invalid.

  19. The FRIABLE1 gene product affects cell adhesion in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Lutz Neumetzler

    Full Text Available Cell adhesion in plants is mediated predominantly by pectins, a group of complex cell wall associated polysaccharides. An Arabidopsis mutant, friable1 (frb1, was identified through a screen of T-DNA insertion lines that exhibited defective cell adhesion. Interestingly, the frb1 plants displayed both cell and organ dissociations and also ectopic defects in organ separation. The FRB1 gene encodes a Golgi-localized, plant specific protein with only weak sequence similarities to known proteins (DUF246. Unlike other cell adhesion deficient mutants, frb1 mutants do not have reduced levels of adhesion related cell wall polymers, such as pectins. Instead, FRB1 affects the abundance of galactose- and arabinose-containing oligosaccharides in the Golgi. Furthermore, frb1 mutants displayed alteration in pectin methylesterification, cell wall associated extensins and xyloglucan microstructure. We propose that abnormal FRB1 action has pleiotropic consequences on wall architecture, affecting both the extensin and pectin matrices, with consequent changes to the biomechanical properties of the wall and middle lamella, thereby influencing cell-cell adhesion.

  20. Split-gene system for hybrid wheat seed production.

    Science.gov (United States)

    Kempe, Katja; Rubtsova, Myroslava; Gils, Mario

    2014-06-24

    Hybrid wheat plants are superior in yield and growth characteristics compared with their homozygous parents. The commercial production of wheat hybrids is difficult because of the inbreeding nature of wheat and the lack of a practical fertility control that enforces outcrossing. We describe a hybrid wheat system that relies on the expression of a phytotoxic barnase and provides for male sterility. The barnase coding information is divided and distributed at two loci that are located on allelic positions of the host chromosome and are therefore "linked in repulsion." Functional complementation of the loci is achieved through coexpression of the barnase fragments and intein-mediated ligation of the barnase protein fragments. This system allows for growth and maintenance of male-sterile female crossing partners, whereas the hybrids are fertile. The technology does not require fertility restorers and is based solely on the genetic modification of the female crossing partner.

  1. Enhanced validamycin production and gene expression at elevated temperature in Streptomyces hygroscopicus subsp. Jingangensis 5008

    Institute of Scientific and Technical Information of China (English)

    LI Lei; BAI LinQuan; ZHOU XiuFen; DENG ZiXin

    2009-01-01

    Cultivation shift from 30℃ to 37℃ significantly enhanced validamycin (VAL) production. Analyzed by reverse-transcripUon PCR, the transcription of three val genes, valA, valK and valG, representing the three operons of the cluster was simultaneously increased at elevated temperature. Furthermore, the transcription of valP and valQ, a pair of two-component regulators in validamycin biosynthetic gene cluster, was also increased at 37℃. Inactivation of valPand valQ reduced validamycin production at 37℃ to the yield level of wild type strain at 30℃, and the val genes showed reduced expression in the mutant LL-8 at 37℃. These results revealed that the two-component regulator valP and valQ contribute to the elevated validamycin production.

  2. Genetic resources for advanced biofuel production described with the Gene Ontology.

    Science.gov (United States)

    Torto-Alalibo, Trudy; Purwantini, Endang; Lomax, Jane; Setubal, João C; Mukhopadhyay, Biswarup; Tyler, Brett M

    2014-01-01

    Dramatic increases in research in the area of microbial biofuel production coupled with high-throughput data generation on bioenergy-related microbes has led to a deluge of information in the scientific literature and in databases. Consolidating this information and making it easily accessible requires a unified vocabulary. The Gene Ontology (GO) fulfills that requirement, as it is a well-developed structured vocabulary that describes the activities and locations of gene products in a consistent manner across all kingdoms of life. The Microbial ENergy processes Gene Ontology () project is extending the GO to include new terms to describe microbial processes of interest to bioenergy production. Our effort has added over 600 bioenergy related terms to the Gene Ontology. These terms will aid in the comprehensive annotation of gene products from diverse energy-related microbial genomes. An area of microbial energy research that has received a lot of attention is microbial production of advanced biofuels. These include alcohols such as butanol, isopropanol, isobutanol, and fuels derived from fatty acids, isoprenoids, and polyhydroxyalkanoates. These fuels are superior to first generation biofuels (ethanol and biodiesel esterified from vegetable oil or animal fat), can be generated from non-food feedstock sources, can be used as supplements or substitutes for gasoline, diesel and jet fuels, and can be stored and distributed using existing infrastructure. Here we review the roles of genes associated with synthesis of advanced biofuels, and at the same time introduce the use of the GO to describe the functions of these genes in a standardized way.

  3. Genetic Resources for Advanced Biofuel Production Described with the Gene Ontology

    Directory of Open Access Journals (Sweden)

    Trudy eTorto-Alalibo

    2014-10-01

    Full Text Available Dramatic increases in research in the area of microbial biofuel production coupled with high-throughput data generation on bioenergy-related microbes has led to a deluge of information in the scientific literature and in databases. Consolidating this information and making it easily accessible requires a unified vocabulary. The Gene Ontology (GO fulfills that requirement, as it is a well-developed structured vocabulary that describes the activities and locations of gene products in a consistent manner across all kingdoms of life. The Microbial Energy Gene Ontology (MENGO: http://www.mengo.biochem.vt.edu project is extending the GO to include new terms to describe microbial processes of interest to bioenergy production. Our effort has added over 600 bioenergy related terms to the Gene Ontology. These terms will aid in the comprehensive annotation of gene products from diverse energy-related microbial genomes. An area of microbial energy research that has received a lot of attention is microbial production of advanced biofuels. These include alcohols such as butanol, isopropanol, isobutanol, and fuels derived from fatty acids, isoprenoids, and polyhydroxyalkanoates. These fuels are superior to first generation biofuels (ethanol and biodiesel esterified from vegetable oil or animal fat, can be generated from non-food feedstock sources, can be used as supplements or substitutes for gasoline, diesel and jet fuels, and can be stored and distributed using existing infrastructure. Here we review the roles of genes associated with synthesis of advanced biofuels, and at the same time introduce the use of the GO to describe the functions of these genes in a standardized way.

  4. Candidate genes for drought tolerance and improved productivity in rice (Oryza sativa L.)

    Indian Academy of Sciences (India)

    M S Vinod; Naveen Sharma; K Manjunatha; Adnan Kanbar; N B Prakash; H E Shashidhar

    2006-03-01

    Candidate genes are sequenced genes of known biological action involved in the development or physiology of a trait. Twenty-one putative candidate genes were designed after an exhaustive search in the public databases along with an elaborate literature survey for candidate gene products and/or regulatory sequences associated with enhanced drought resistance. The downloaded sequences were then used to design primers considering the flanking sequences as well. Polymerase chain reaction (PCR) performed on 10 diverse cultivars that involved Japonica, Indica and local accessions, revealed 12 polymorphic candidate genes. Seven polymorphic candidate genes were then utilized to genotype 148 individuals of CT9993 × IR62266 doubled haploid (DH) mapping population. The segregation data were tested for deviation from the expected Mendelian ratio (1:1) using a Chi-square test (<1%). Based on this, four candidate genes were assessed to be significant and the remaining three, as non-significant. All the significant candidate genes were biased towards CT9993, the female parent in the DH mapping population. Single-marker analysis strongly associated ( < 1%) them to different traits under both well-watered and low-moisture stress conditions. Two candidate genes, EXP15 and EXP13, were found to be associated with root number and silicon content in the stem respectively, under both well-watered and low-moisture stress conditions.

  5. ROS production during symbiotic infection suppresses pathogenesis-related gene expression.

    Science.gov (United States)

    Peleg-Grossman, Smadar; Melamed-Book, Naomi; Levine, Alex

    2012-03-01

    Leguminous plants have exclusive ability to form symbiotic relationship with soil bacteria of the genus Rhizobium. Symbiosis is a complex process that involves multiple molecular signaling activities, such as calcium fluxes, production of reactive oxygen species (ROS) and synthesis of nodulation genes. We analyzed the role of ROS in defense gene expression in Medicago truncatula during symbiosis and pathogenesis. Studies in Arabidopsis thaliana showed that the induction of pathogenesis-related (PR) genes during systemic acquired resistance (SAR) is regulated by NPR1 protein, which resides in the cytoplasm as an oligomer. After oxidative burst and return of reducing conditions, the NPR1 undergoes monomerization and becomes translocated to the nucleus, where it functions in PR genes induction. We show that ROS production is both stronger and longer during symbiotic interactions than during interactions with pathogenic, nonhost or common nonpathogenic soil bacteria. Moreover, root cells inoculated with Sinorhizobium meliloti accumulated ROS in the cytosol but not in vacuoles, as opposed to Pseudomonas putida inoculation or salt stress treatment. Furthermore, increased ROS accumulation by addition of H₂O₂ reduced the PR gene expression, while catalase had an opposite effect, establishing that the PR gene expression is opposite to the level of cytoplasmic ROS. In addition, we show that salicylic acid pretreatment significantly reduced ROS production in root cells during symbiotic interaction.

  6. Products of lipid, protein and RNA oxidation as signals and regulators of gene expression in plants

    Directory of Open Access Journals (Sweden)

    Jagna eChmielowska-Bąk

    2015-06-01

    Full Text Available Reactive oxygen species (ROS are engaged in several processes essential for normal cell functioning, such as differentiation, anti-microbial defense, stimulus sensing and signaling. Interestingly, recent studies imply that cellular signal transduction and gene regulation are mediated not only directly by ROS but also by the molecules derived from ROS-mediated oxidation. Lipid peroxidation leads to non-enzymatic formation of oxylipins. These molecules were shown to modulate expression of signaling associated genes including genes encoding phosphatases, kinases and transcription factors. Oxidized peptides derived from protein oxidation might be engaged in organelle-specific ROS signaling. In turn, oxidation of particular mRNAs leads to decrease in the level of encoded proteins and thus, contributes to the post-transcriptional regulation of gene expression. Present mini review summarizes latest findings concerning involvement of products of lipid, protein and RNA oxidation in signal transduction and gene regulation.

  7. Engineering validamycin production by tandem deletion of γ-butyrolactone receptor genes in Streptomyces hygroscopicus 5008.

    Science.gov (United States)

    Tan, Gao-Yi; Peng, Yao; Lu, Chenyang; Bai, Linquan; Zhong, Jian-Jiang

    2015-03-01

    Paired homologs of γ-butyrolactone (GBL) biosynthesis gene afsA and GBL receptor gene arpA are located at different positions in genome of Streptomyces hygroscopicus 5008. Inactivation of afsA homologs dramatically decreased biosynthesis of validamycin, an important anti-fungal antibiotic and a critical substrate for antidiabetic drug synthesis, and the deletion of arpA homologs increased validamycin production by 26% (ΔshbR1) and 20% (ΔshbR3). By double deletion, the ΔshbR1/R3 mutant showed higher transcriptional levels of adpA-H (the S. hygroscopicus ortholog of the global regulatory gene adpA) and validamycin biosynthetic genes, and validamycin production increased by 55%. Furthermore, by engineering a high-producing industrial strain via tandem deletion of GBL receptor genes, validamycin production and productivity were enhanced from 19 to 24 g/L (by 26%) and from 6.7 to 9.7 g/L(-1) d(-1) (by 45%), respectively, which was the highest ever reported. The strategy demonstrated here may be useful to engineering other Streptomyces spp. with multiple pairs of afsA-arpA homologs.

  8. Inflammatory cues modulate the expression of secretory product genes, Golgi sulfotransferases and sulfomucin production in LS174T cells.

    Science.gov (United States)

    Croix, Jennifer A; Bhatia, Shikha; Gaskins, H Rex

    2011-12-01

    The signals that mediate goblet cell expression of specific mucin chemotypes are poorly defined. Animal and in vitro studies show that acidomucin chemotypes may be altered by inflammation and changes in intestinal microbiota. To examine factors that may elicit this response, human adenocarcinoma-derived LS174T cells, which have a goblet cell-like phenotype and produce both sulfo- and sialomucins, were used to examine the effects of selected microbial and host factors on expression of goblet cell secretory product genes, sulfotransferases and sulfomucin production. Expression of genes encoding mucin 2 (MUC2), resistin-like molecule β (RETNLB), and trefoil factor 3 (TFF3) and Golgi sulfotransferases, carbohydrate (N-acetylglucosamine 6-O) sulfotransferase 5 (CHST5) and galactose-3-O-sulfotransferase 2 (GAL3ST2), was measured by quantitative reverse transcriptase-polymerase chain reaction following treatment with bacterial flagellin, tumor necrosis factor α (TNF-α) or the mucogenic cytokine interleukin-13 (IL-13). Expression of the toll-like receptor 5 (TLR5) gene was also analysed. Sulfomucin expression was examined via high-iron diamide/alcian blue (HID/AB) histochemistry and immunofluorescent staining for the Sulfo Le(a) antigen, which is synthesized in part by GAL3ST2. Flagellin, IL-13 and TNF-α all significantly increased GAL3ST2, MUC2, TFF3 and TLR5 expression, while only IL-13 increased RETNLB and CHST5 expression. Based on HID/AB histochemistry, mucin sulfation was significantly increased in response to both flagellin and IL-13 but not TNF-α. Only treatment with flagellin increased the expression of the Sulfo Le(a) antigen. Collectively, these results indicate that bacterial flagellin, IL-13 and TNF-α differentially modulate the expression of goblet cell secretory product genes, sulfotransferases and sulfomucin production.

  9. Investigation of genes involved in nisin production in Enterococcus spp. strains isolated from raw goat milk.

    Science.gov (United States)

    Perin, Luana Martins; Todorov, Svetoslav Dimitrov; Nero, Luís Augusto

    2016-09-01

    Different strains of Lactococcus lactis are capable of producing the bacteriocin nisin. However, genetic transfer mechanisms allow the natural occurrence of genes involved in nisin production in members of other bacterial genera, such as Enterococcus spp. In a previous study, nisA was identified in eight enterococci capable of producing antimicrobial substances. The aim of this study was to verify the presence of genes involved in nisin production in Enterococcus spp. strains, as well as nisin expression. The nisA genes from eight Enterococcus spp. strains were sequenced and the translated amino acid sequences were compared to nisin amino-acid sequences previously described in databases. Although containing nisin structural and maturation related genes, the enterococci strains tested in the present study did not present the immunity related genes (nisFEG and nisI). The translated sequences of nisA showed some point mutations, identical to those presented by Lactococcus strains isolated from goat milk. All enterococci were inhibited by nisin, indicating the absence of immunity and thus that nisin cannot be expressed. This study demonstrated for the first time the natural occurrence of nisin structural genes in Enterococcus strains and highlights the importance of providing evidence of a link between the presence of bacteriocin genes and their expression.

  10. Production of indole antibiotics induced by exogenous gene derived from sponge metagenomes.

    Science.gov (United States)

    Takeshige, Yuya; Egami, Yoko; Wakimoto, Toshiyuki; Abe, Ikuro

    2015-05-01

    Sponge metagenomes are accessible genetic sources containing genes and gene clusters responsible for the biosynthesis of sponge-derived bioactive natural products. In this study, we obtained the clone pDC112, producing turbomycin A and 2,2-di(3-indolyl)-3-indolone, based on the functional screening of the metagenome library derived from the marine sponge Discodermia calyx. The subcloning experiment identified ORF 25, which is homologous to inosine 5'-monophosphate dehydrogenase and required for the production of 2,2-di(3-indolyl)-3-indolone in Escherichia coli.

  11. GeneViTo: Visualizing gene-product functional and structural features in genomic datasets

    Directory of Open Access Journals (Sweden)

    Promponas Vasilis J

    2003-10-01

    Full Text Available Abstract Background The availability of increasing amounts of sequence data from completely sequenced genomes boosts the development of new computational methods for automated genome annotation and comparative genomics. Therefore, there is a need for tools that facilitate the visualization of raw data and results produced by bioinformatics analysis, providing new means for interactive genome exploration. Visual inspection can be used as a basis to assess the quality of various analysis algorithms and to aid in-depth genomic studies. Results GeneViTo is a JAVA-based computer application that serves as a workbench for genome-wide analysis through visual interaction. The application deals with various experimental information concerning both DNA and protein sequences (derived from public sequence databases or proprietary data sources and meta-data obtained by various prediction algorithms, classification schemes or user-defined features. Interaction with a Graphical User Interface (GUI allows easy extraction of genomic and proteomic data referring to the sequence itself, sequence features, or general structural and functional features. Emphasis is laid on the potential comparison between annotation and prediction data in order to offer a supplement to the provided information, especially in cases of "poor" annotation, or an evaluation of available predictions. Moreover, desired information can be output in high quality JPEG image files for further elaboration and scientific use. A compilation of properly formatted GeneViTo input data for demonstration is available to interested readers for two completely sequenced prokaryotes, Chlamydia trachomatis and Methanococcus jannaschii. Conclusions GeneViTo offers an inspectional view of genomic functional elements, concerning data stemming both from database annotation and analysis tools for an overall analysis of existing genomes. The application is compatible with Linux or Windows ME-2000-XP operating

  12. Biofilm formation, phenotypic production of cellulose and gene expression in Salmonella enterica decrease under anaerobic conditions.

    Science.gov (United States)

    Lamas, A; Miranda, J M; Vázquez, B; Cepeda, A; Franco, C M

    2016-12-05

    Salmonella enterica subsp. enterica is one of the main food-borne pathogens. This microorganism combines an aerobic life outside the host with an anaerobic life within the host. One of the main concerns related to S. enterica is biofilm formation and cellulose production. In this study, biofilm formation, morphotype, cellulose production and transcription of biofilm and quorum sensing-related genes of 11 S. enterica strains were tested under three different conditions: aerobiosis, microaerobiosis, and anaerobiosis. The results showed an influence of oxygen levels on biofilm production. Biofilm formation was significantly higher (Pbiofilm and quorum sensing-related genes. Thus, the results from this study indicate that biofilm formation and cellulose production are highly influenced by atmospheric conditions. This must be taken into account as contamination with these bacteria can occur during food processing under vacuum or modified atmospheres.

  13. 1,3-Propanediol production by Escherichia coli using genes from Citrobacter freundii atcc 8090.

    Science.gov (United States)

    Przystałowska, Hanna; Zeyland, Joanna; Kośmider, Alicja; Szalata, Marlena; Słomski, Ryszard; Lipiński, Daniel

    2015-01-01

    Compared with chemical synthesis, fermentation has the advantage of mass production at low cost, and has been used in the production of various industrial chemicals. As a valuable organic compound, 1,3-propanediol (1,3-PDO) has numerous applications in the production of polymers, lubricants, cosmetics and medicines. Here, conversion of glycerol (a renewable substrate and waste from biodiesel production) to 1,3-PDO by E. coli bacterial strain carrying altered glycerol metabolic pathway was investigated. Two gene constructs containing the 1,3-PDO operon from Citrobacter freundii (pCF1 and pCF2) were used to transform the bacteria. The pCF1 gene expression construct contained dhaBCE genes encoding the three subunits of glycerol dehydratase, dhaF encoding the large subunit of the glycerol dehydratase reactivation factor and dhaG encoding the small subunit of the glycerol dehydratase reactivating factor. The pCF2 gene expression construct contained the dhaT gene encoding the 1,3-propanediol dehydrogenase. Expression of the genes cloned in the above constructs was under regulation of the T7lac promoter. RT-PCR, SDS-PAGE analyses and functional tests confirmed that 1,3-PDO synthesis pathway genes were expressed at the RNA and protein levels, and worked flawlessly in the heterologous host. In a batch flask culture, in a short time applied just to identify the 1,3-PDO in a preliminary study, the recombinant E. coli bacteria produced 1.53 g/L of 1,3-PDO, using 21.2 g/L of glycerol in 72 h. In the Sartorius Biostat B Plus reactor, they produced 11.7 g/L of 1,3-PDO using 24.2 g/L of glycerol, attaining an efficiency of 0.58 [mol1,3-PDO/molglycerol].

  14. Identification and engineering of regulation-related genes toward improved kasugamycin production.

    Science.gov (United States)

    Zhu, Chenchen; Kang, Qianjin; Bai, Linquan; Cheng, Lin; Deng, Zixin

    2016-02-01

    Kasugamycin, produced by Streptomyces kasugaensis and Streptomyces microaureus, is an important amino-glycoside family antibiotic and widely used for veterinary and agricultural applications. In the left flanking region of the previously reported kasugamycin gene cluster, four additional genes (two-component system kasW and kasX, MerR-family kasV, and isoprenylcysteine carboxyl methyltransferase kasS) were identified both in the low-yielding S. kasugaensis BCRC12349 and high-yielding S. microaureus XM301. Deletion of regulatory gene kasT abolished kasugamycin production, and its overexpression in BCRC12349 resulted in an increased titer by 186 %. Deletion of kasW, kasX, kasV, and kasS improved kasugamycin production by 12, 19, 194, and 22 %, respectively. qRT-PCR analysis demonstrated that the transcription of kas genes was significantly increased in all the four mutants. Similar gene inactivation was performed in the high-yielding strain S. microaureus XM301. As expected, the deletion of kasW/X resulted in a 58 % increase of the yield from 6 to 9.5 g/L. However, the deletion of kasV and over-expression of kasT had no obvious effect, and the disruption of kasS surprisingly decreased kasugamycin production. In addition, trans-complementation of the kasS mutant with a TTA codon-mutated kasS increased the kasugamycin yield by 20 %. A much higher transcription of kas genes was detected in the high-yielding XM301 than in the low-yielding BCRC12349, which may partially account for the discrepancy of gene inactivation effects between them. Our work not only generated engineered strains with improved kasugamycin yield, but also pointed out that different strategies on manipulating regulatory-related genes should be considered for low-yielding or high-yielding strains.

  15. Regulatory structures for gene therapy medicinal products in the European Union.

    Science.gov (United States)

    Klug, Bettina; Celis, Patrick; Carr, Melanie; Reinhardt, Jens

    2012-01-01

    Taking into account the complexity and technical specificity of advanced therapy medicinal products: (gene and cell therapy medicinal products and tissue engineered products), a dedicated European regulatory framework was needed. Regulation (EC) No. 1394/2007, the "ATMP Regulation" provides tailored regulatory principles for the evaluation and authorization of these innovative medicines. The majority of gene or cell therapy product development is carried out by academia, hospitals, and small- and medium-sized enterprises (SMEs). Thus, acknowledging the particular needs of these types of sponsors, the legislation also provides incentives for product development tailored to them. The European Medicines Agency (EMA) and, in particular, its Committee for Advanced Therapies (CAT) provide a variety of opportunities for early interaction with developers of ATMPs to enable them to have early regulatory and scientific input. An important tool to promote innovation and the development of new medicinal products by micro-, small-, and medium-sized enterprises is the EMA's SME initiative launched in December 2005 to offer financial and administrative assistance to smaller companies. The European legislation also foresees the involvement of stakeholders, such as patient organizations, in the development of new medicines. Considering that gene therapy medicinal products are developed in many cases for treatment of rare diseases often of monogenic origin, the involvement of patient organizations, which focus on rare diseases and genetic and congenital disorders, is fruitful. Two such organizations are represented in the CAT. Research networks play another important role in the development of gene therapy medicinal products. The European Commission is funding such networks through the EU Sixth Framework Program.

  16. Isolated fungal promoters and gene transcription terminators and methods of protein and chemical production in a fungus

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu; Lasure, Linda L; Magnuson, Jon K

    2014-05-27

    The present invention encompasses isolated gene regulatory elements and gene transcription terminators that are differentially expressed in a native fungus exhibiting a first morphology relative to the native fungus exhibiting a second morphology. The invention also encompasses a method of utilizing a fungus for protein or chemical production. A transformed fungus is produced by transforming a fungus with a recombinant polynucleotide molecule. The recombinant polynucleotide molecule contains an isolated polynucleotide sequence linked operably to another molecule comprising a coding region of a gene of interest. The gene regulatory element and gene transcription terminator may temporally and spatially regulate expression of particular genes for optimum production of compounds of interest in a transgenic fungus.

  17. Isolated fungal promoters and gene transcription terminators and methods of protein and chemical production in a fungus

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu; Lasure, Linda L; Magnuson, Jon K

    2014-05-27

    The present invention encompasses isolated gene regulatory elements and gene transcription terminators that are differentially expressed in a native fungus exhibiting a first morphology relative to the native fungus exhibiting a second morphology. The invention also encompasses a method of utilizing a fungus for protein or chemical production. A transformed fungus is produced by transforming a fungus with a recombinant polynucleotide molecule. The recombinant polynucleotide molecule contains an isolated polynucleotide sequence linked operably to another molecule comprising a coding region of a gene of interest. The gene regulatory element and gene transcription terminator may temporally and spatially regulate expression of particular genes for optimum production of compounds of interest in a transgenic fungus.

  18. Isolated Fungal Promoters and Gene Transcription Terminators and Methods of Protein and Chemical Production in a Fungus

    Science.gov (United States)

    Dai, Ziyu; Lasure, Linda L.; Magnuson, Jon K.

    2008-11-11

    The present invention encompasses isolated gene regulatory elements and gene transcription terminators that are differentially expressed in a native fungus exhibiting a first morphology relative to the native fungus exhibiting a second morphology. The invention also encompasses a method of utilizing a fungus for protein or chemical production. A transformed fungus is produced by transforming a fungus with a recombinant polynucleotide molecule. The recombinant polynucleotide molecule contains an isolated polynucleotide sequence linked operably to another molecule comprising a coding region of a gene of interest. The gene regulatory element and gene transcription terminator may temporally and spatially regulate expression of particular genes for optimum production of compounds of interest in a transgenic fungus.

  19. Effects of medium composition on the production of plasmid DNA vector potentially for human gene therapy

    Institute of Scientific and Technical Information of China (English)

    XU Zhi-nan; SHEN Wen-he; CHEN Hao; CEN Pei-lin

    2005-01-01

    Plasmid vector is increasingly applied to gene therapy or gene vaccine. The production of plasmid pCMV-AP3 for cancer gene therapy was conducted in a modified MBL medium using a recombinant E. coli BL21 system. The effects of different MMBL components on plasmid yield, cell mass and specific plasmid DNA productivity were evaluated on shake-flask scale. The results showed that glucose was the optimal carbon source. High plasmid yield (58.3 mg/L) was obtained when 5.0 g/L glucose was added to MMBL. Glycerol could be chosen as a complementary carbon source because of the highest specific plasmid productivity (37.9 mg DNA/g DCW). After tests of different levels of nitrogen source and inorganic phosphate, a modified MMBL medium was formulated for optimal plasmid production. Further study showed that the initial acetate addition (less than 4.0 g/L) in MMBL improved plasmid production significantly, although it inhibited cell growth. The results will be useful for large-scale plasmid production using recombinant E. coli system.

  20. Prolactin (PRL) and prolactin receptor (PRLR) genes and their role in poultry production traits.

    Science.gov (United States)

    Wilkanowska, Anna; Mazurowski, Artur; Mroczkowski, Sławomir; Kokoszyński, Dariusz

    2014-01-01

    Prolactin (PRL), secreted from the anterior pituitary, plays extensive roles in osmoregulation, corpus luteum formation, mammogenesis, lactogenesis, lactopoiesis, and production of crop milk. In birds, prolactin (PRL) is generally accepted as crucial to the onset and maintenance of broodiness. All the actions of prolactin (PRL) hormone are mediated by its receptor (PRLR), which plays an important role in the PRL signal transduction cascade. It has been well established that the PRL gene is closely associated to the onset and maintenance of broody behavior, and could be a genetic marker in breeding against broodiness in chickens. Meanwhile, the prolactin receptor (PRLR) gene is regarded as a candidate genetic marker for reproductive traits. PRLR is also an important regulator gene for cell growth and differentiation. The identified polymorphism of this gene is mainly viewed in terms of egg production traits. Due to different biological activities attributed to PRL and PRLR, they can be used as major candidate genes in molecular animal breeding programs. Characterization of PRL and PRLR genes helps to elucidate their roles in birds and provides insights into the regulatory mechanisms of PRL and PRLR expression conserved in birds and mammals.

  1. Polyhydroxyalkanoate production from sucrose by Cupriavidus necator strains harboring csc genes from Escherichia coli W.

    Science.gov (United States)

    Arikawa, Hisashi; Matsumoto, Keiji; Fujiki, Tetsuya

    2017-09-09

    Cupriavidus necator H16 is the most promising bacterium for industrial production of polyhydroxyalkanoates (PHAs) because of their remarkable ability to accumulate them in the cells. With genetic modifications, this bacterium can produce poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx), which has better physical properties, as well as poly(3-hydroxybutyrate) (PHB) using plant oils and sugars as a carbon source. Considering production cost, sucrose is a very attractive raw material because it is inexpensive; however, this bacterium cannot assimilate sucrose. Here, we used the sucrose utilization (csc) genes of Escherichia coli W to generate C. necator strains that can assimilate sucrose. Especially, glucose-utilizing recombinant C. necator strains harboring the sucrose hydrolase gene (cscA) and sucrose permease gene (cscB) of E. coli W grew well on sucrose as a sole carbon source and accumulated PHB. In addition, strains introduced with a crotonyl-CoA reductase gene (ccr), ethylmalonyl-CoA decarboxylase gene (emd), and some other genetic modifications besides the csc genes and the glucose-utilizing mutations produced PHBHHx with a 3-hydroxyhexanoate (3HHx) content of maximum approximately 27 mol% from sucrose. Furthermore, when one of the PHBHHx-producing strains was cultured with sucrose solution in a fed-batch fermentation, PHBHHx with a 3HHx content of approximately 4 mol% was produced and reached 113 g/L for 65 h, which is approximately 1.5-fold higher than that produced using glucose solution.

  2. The dam replacing gene product enhances Neisseria gonorrhoeae FA1090 viability and biofilm formation.

    Science.gov (United States)

    Kwiatek, Agnieszka; Bacal, Pawel; Wasiluk, Adrian; Trybunko, Anastasiya; Adamczyk-Poplawska, Monika

    2014-01-01

    Many Neisseriaceae do not exhibit Dam methyltransferase activity and, instead of the dam gene, possess drg (dam replacing gene) inserted in the leuS/dam locus. The drg locus in Neisseria gonorrhoeae FA1090 has a lower GC-pairs content (40.5%) compared to the whole genome of N. gonorrhoeae FA1090 (52%). The gonococcal drg gene encodes a DNA endonuclease Drg, with GmeATC specificity. Disruption of drg or insertion of the dam gene in gonococcal genome changes the level of expression of genes as shown by transcriptome analysis. For the drg-deficient N. gonorrhoeae mutant, a total of 195 (8.94% of the total gene pool) genes exhibited an altered expression compared to the wt strain by at least 1.5 fold. In dam-expressing N. gonorrhoeae mutant, the expression of 240 genes (11% of total genes) was deregulated. Most of these deregulated genes were involved in translation, DNA repair, membrane biogenesis and energy production as shown by cluster of orthologous group analysis. In vivo, the inactivation of drg gene causes the decrease of the number of live neisserial cells and long lag phase of growth. The insertion of dam gene instead of drg locus restores cell viability. We have also shown that presence of the drg gene product is important for N. gonorrhoeae FA1090 in adhesion, including human epithelial cells, and biofilm formation. Biofilm produced by drg-deficient strain is formed by more dispersed cells, compared to this one formed by parental strain as shown by scanning electron and confocal microscopy. Also adherence assays show a significantly smaller biomass of formed biofilm (OD570 = 0.242 ± 0.038) for drg-deficient strain, compared to wild-type strain (OD570 = 0.378 ± 0.057). Dam-expressing gonococcal cells produce slightly weaker biofilm with cells embedded in an extracellular matrix. This strain has also a five times reduced ability for adhesion to human epithelial cells. In this context, the presence of Drg is more advantageous for N. gonorrhoeae biology than

  3. Ethanol production by Escherichia coli strains co-expressing Zymomonas PDC and ADH genes

    Energy Technology Data Exchange (ETDEWEB)

    Ingram, Lonnie O. (Gainesville, FL); Conway, Tyrrell (Lincoln, NE); Alterthum, Flavio (Gainesville, FL)

    1991-01-01

    A novel operon and plasmids comprising genes which code for the alcohol dehydrogenase and pyruvate decarboxylase activities of Zymomonas mobilis are described. Also disclosed are methods for increasing the growth of microorganisms or eukaryotic cells and methods for reducing the accumulation of undesirable metabolic products in the growth medium of microorganisms or cells.

  4. Assembly of Highly Standardized Gene Fragments for High-Level Production of Porphyrins in E. coli

    DEFF Research Database (Denmark)

    Nielsen, Morten Thrane; Madsen, Karina Marie; Seppala, Susanna;

    2015-01-01

    to formulate a molecular cloning pipeline and iteratively assemble and optimize a six-gene pathway for protoporphyrin IX synthesis in Escherichia coli. State of the art production levels were achieved through two simple cycles of engineering and screening. The principles defined here are generally applicable...

  5. ALOX5 gene variants affect eicosanoid production and response to fish oil supplementation

    Science.gov (United States)

    The objective of this study was to determine whether 5-lipoxygenase (ALOX5) gene variants associated with cardiovascular disease affect eicosanoid production by monocytes. The study was a randomized, double-masked, parallel intervention trial with fish oil (5.0 g of fish oil daily, containing 2.0 g ...

  6. Functional analysis of Photosystem I light-harvesting complexes (Lhca) gene products of Chlamydomonas reinhardtii

    NARCIS (Netherlands)

    Mozzo, Milena; Mantelli, Manuela; Passarini, Francesca; Caffarri, Stefano; Croce, Roberta; Bassi, Roberto

    2010-01-01

    The outer antenna system of Chlamydomonas reinhardtii Photosystem I is composed of nine gene products, but due to difficulty in purification their individual properties are not known. In this work, the functional properties of the nine Lhca antennas of Chlamydomonas, have been investigated upon expr

  7. A positive feedback-based gene circuit to increase the production of a membrane protein

    Directory of Open Access Journals (Sweden)

    Gennis Robert B

    2010-05-01

    Full Text Available Abstract Background Membrane proteins are an important class of proteins, playing a key role in many biological processes, and are a promising target in pharmaceutical development. However, membrane proteins are often difficult to produce in large quantities for the purpose of crystallographic or biochemical analyses. Results In this paper, we demonstrate that synthetic gene circuits designed specifically to overexpress certain genes can be applied to manipulate the expression kinetics of a model membrane protein, cytochrome bd quinol oxidase in E. coli, resulting in increased expression rates. The synthetic circuit involved is an engineered, autoinducer-independent variant of the lux operon activator LuxR from V. fischeri in an autoregulatory, positive feedback configuration. Conclusions Our proof-of-concept experiments indicate a statistically significant increase in the rate of production of the bd oxidase membrane protein. Synthetic gene networks provide a feasible solution for the problem of membrane protein production.

  8. Hematological- and Neurological-Expressed Sequence 1 Gene Products in Progenitor Cells during Newt Retinal Development

    Directory of Open Access Journals (Sweden)

    Tatsushi Goto

    2012-01-01

    Full Text Available Urodele amphibians such as Japanese common newts have a remarkable ability to regenerate their injured neural retina, even as adults. We found that hematological- and neurological-expressed sequence 1 (Hn1 gene was induced in depigmented retinal pigment epithelial (RPE cells, and its expression was maintained at later stages of newt retinal regeneration. In this study, we investigated the distribution of the HN1 protein, the product of the Hn1 gene, in the developing retinas. Our immunohistochemical analyses suggested that the HN1 protein was highly expressed in an immature retina, and the subcellular localization changed during this retinogenesis as observed in newt retinal regeneration. We also found that the expression of Hn1 gene was not induced in mouse after retinal removal. Our results showed that Hn1 gene can be useful for detection of undifferentiated and dedifferentiated cells during both newt retinal development and regeneration.

  9. The Gene bldA, a regulator of morphological differentiation and antibiotic production in streptomyces.

    Science.gov (United States)

    Hackl, Stefanie; Bechthold, Andreas

    2015-07-01

    Streptomyces species are well known for their particular features of morphological differentiation. On solid agar, a mold-like aerial mycelium is formed and spores are produced, in which the bld genes play a crucial role. In S. coelicolor, mutations in one specific bld gene called bldA led to a "naked" phenotype lacking aerial hyphae and spores. This peculiar behavior became a major interest for scientific research in the past and it was revealed that bldA is coding for a unique tRNA able to translate a UUA codon into the amino acid leucine. UUA codons are a very rare property of G + C-rich Streptomyces genomes. The impact of bldA on morphology can in parts be attributed to the regulatory effect of bldA on the translational level, because TTA-containing genes can only be translated into their corresponding protein in the presence of a fully functioning bldA gene. In addition to the visible effect of bldA expression on the phenotype of S. coelicolor, bldA mutants were also deficient in antibiotic production. This led to the assumption that the role of bldA must exceed translational control. Many TTA-containing genes are coding for transcriptional regulators which are activating or repressing the transcription of many more genes. Proteomics and transcriptomics are two powerful methods for identifying bldA target genes and it was possible to assign also post-translational regulation to bldA. This review wants to give a short overview on the importance of bldA as a regulator of morphological differentiation and antibiotic production by switching on "silent" gene clusters in Streptomyces.

  10. Aerobic conditions increase isoprenoid biosynthesis pathway gene expression levels for carotenoid production in Enterococcus gilvus.

    Science.gov (United States)

    Hagi, Tatsuro; Kobayashi, Miho; Nomura, Masaru

    2015-06-01

    Some lactic acid bacteria that harbour carotenoid biosynthesis genes (crtNM) can produce carotenoids. Although aerobic conditions can increase carotenoid production and crtNM expression levels, their effects on the pathways that synthesize carotenoid precursors such as mevalonate and isoprene are not completely understood. In this study, we investigated whether aerobic conditions affected gene expression levels involved in the isoprenoid biosynthesis pathway that includes the mevalonate and isoprene biosynthesis pathways in Enterococcus gilvus using real-time quantitative reverse transcription PCR. NADH oxidase (nox) and superoxide dismutase (sod) gene expression levels were investigated as controls for aerobic conditions. The expression levels of nox and sod under aerobic conditions were 7.2- and 8.0-fold higher, respectively, than those under anaerobic conditions. Aerobic conditions concomitantly increased the expression levels of crtNM carotenoid biosynthesis genes. HMG-CoA synthase gene expression levels in the mevalonate pathway were only slightly increased under aerobic conditions, whereas the expression levels of HMG-CoA reductase and five other genes in the isoprene biosynthesis pathways were 1.2-2.3-fold higher than those under anaerobic conditions. These results demonstrated that aerobic conditions could increase the expression levels of genes involved in the isoprenoid biosynthesis pathway via mevalonate in E. gilvus.

  11. Increasing cocoa butter-like lipid production of Saccharomyces cerevisiae by expression of selected cocoa genes

    DEFF Research Database (Denmark)

    Wei, Yongjun; Gossing, Michael; Bergenholm, David

    2017-01-01

    Cocoa butter (CB) extracted from cocoa beans mainly consists of three different kinds of triacylglycerols (TAGs), 1,3-dipalmitoyl-2-oleoyl-glycerol (POP, C16:0-C18:1-C16:0), 1-palmitoyl-3-stearoyl-2-oleoyl-glycerol(POS,C16:0C18:1-C18:0) and 1,3-distearoyl-2-oleoyl-glycerol (SOS, C18:0-C18:1-C18....... TAG synthesis is mainly catalyzed by three enzymes: glycerol-3-phosphate acyltransferase (GPAT), lysophospholipid acyltransferase (LPAT) and diacylglycerol acyltransferase (DGAT). In order to produce CBL in S. cerevisiae, we selected six cocoa genes encoding GPAT, LPAT and DGAT potentially responsible...... for CB biosynthesis from the cocoa genome using a phylogenetic analysis approach. By expressing the selected cocoa genes in S. cerevisiae, we successfully increased total fatty acid production, TAG production and CBL production in some S. cerevisiae strains. The relative CBL content in three yeast...

  12. Effect of Different Carbon Source on Expression of Carotenogenic Genes and Astaxanthin Production in Xanthophyllomyces dendrorhous

    Directory of Open Access Journals (Sweden)

    Wei Wu

    2013-10-01

    Full Text Available The present research gives an insight into astaxanthin production, as well as transcription differences of four key carotenogenic genes, in Xanthophyllomyces dendrorhous when cultured with various carbon sources and soybean oil as co-substrates. Glucose was found to be the carbon source with best culture growth and astaxanthin production and the addition of 2% (v/v soybean oil resulted in even higher astaxanthin producing. In addition, four carotenogenic genes encoding geranylgeranyl diphosphate synthase (crtE, phytoene desaturase (crtl, phytoene synthase lycopene cyclase(crtYB, and astaxanthin synthetase (ast, respectively, were demonstrated to be associated with different transcription levels under various substrates. The present study suggests the effectiveness of manipulating the metabolic regulation by using different carbon sources, in order to improve the production of astaxanthin.

  13. Correlation of gene expression and protein production rate - a system wide study

    Directory of Open Access Journals (Sweden)

    Arvas Mikko

    2011-12-01

    Full Text Available Abstract Background Growth rate is a major determinant of intracellular function. However its effects can only be properly dissected with technically demanding chemostat cultivations in which it can be controlled. Recent work on Saccharomyces cerevisiae chemostat cultivations provided the first analysis on genome wide effects of growth rate. In this work we study the filamentous fungus Trichoderma reesei (Hypocrea jecorina that is an industrial protein production host known for its exceptional protein secretion capability. Interestingly, it exhibits a low growth rate protein production phenotype. Results We have used transcriptomics and proteomics to study the effect of growth rate and cell density on protein production in chemostat cultivations of T. reesei. Use of chemostat allowed control of growth rate and exact estimation of the extracellular specific protein production rate (SPPR. We find that major biosynthetic activities are all negatively correlated with SPPR. We also find that expression of many genes of secreted proteins and secondary metabolism, as well as various lineage specific, mostly unknown genes are positively correlated with SPPR. Finally, we enumerate possible regulators and regulatory mechanisms, arising from the data, for this response. Conclusions Based on these results it appears that in low growth rate protein production energy is very efficiently used primarly for protein production. Also, we propose that flux through early glycolysis or the TCA cycle is a more fundamental determining factor than growth rate for low growth rate protein production and we propose a novel eukaryotic response to this i.e. the lineage specific response (LSR.

  14. Production of 2-ketoisocaproate with Corynebacterium glutamicum strains devoid of plasmids and heterologous genes.

    Science.gov (United States)

    Vogt, Michael; Haas, Sabine; Polen, Tino; van Ooyen, Jan; Bott, Michael

    2015-03-01

    2-Ketoisocaproate (KIC), the last intermediate in l-leucine biosynthesis, has various medical and industrial applications. After deletion of the ilvE gene for transaminase B in l-leucine production strains of Corynebacterium glutamicum, KIC became the major product, however, the strains were auxotrophic for l-isoleucine. To avoid auxotrophy, reduction of IlvE activity by exchanging the ATG start codon of ilvE by GTG was tested instead of an ilvE deletion. The resulting strains were indeed able to grow in glucose minimal medium without amino acid supplementation, but at the cost of lowered growth rates and KIC production parameters. The best production performance was obtained with strain MV-KICF1, which carried besides the ilvE start codon exchange three copies of a gene for a feedback-resistant 2-isopropylmalate synthase, one copy of a gene for a feedback-resistant acetohydroxyacid synthase and deletions of ltbR and iolR encoding transcriptional regulators. In the presence of 1 mM l-isoleucine, MV-KICF1 accumulated 47 mM KIC (6.1 g l(-1)) with a yield of 0.20 mol/mol glucose and a volumetric productivity of 1.41 mmol KIC l(-1)  h(-1). Since MV-KICF1 is plasmid free and lacks heterologous genes, it is an interesting strain for industrial application and as platform for the production of KIC-derived compounds, such as 3-methyl-1-butanol.

  15. Increase of Clavulanic acid production by using recombinant Streptomyces clavuligerus strain including claR gene

    Directory of Open Access Journals (Sweden)

    Maryam Kay

    2014-07-01

    Full Text Available   Introduction : Clavulanic acid is a major β-lactam antibiotic which is produced by Streptomyces clavuligerus. Clavulanic acid is used in combination of strong but sensitive to β-lactamase antibiotics. The claR gene has an important role in regulation of clavulanic acid production and is needed for the expression of the genes in final step of clavulanic acid biosynthesis.   Materials and methods: The recombinant construct pMTclaR which contains claR gene is obtained from Isfahan University and plasmid extraction was done from Streptomyces lividans for next steps. The Streptomyces clavuligerus protoplast was prepared and transformation was done by using polyethylene glycol. Transformation was confirmed by plasmid extraction and PCR. Finally, bioassay method was used to survey the effect of extra copy of claR on clavulanic acid production .   Results : The typical chalky white colony of Streptomyces clavuligerus was seen on GYME plates containing thiostrepton antibiotic. Plasmid extraction was initially carried out. Furthermore, PCR reaction was done by claR specific primers and the 1334 bp band which was belonging to claR was detected. Finally, the bioassay was done and the diameters of zone of inhibition in control and sample were compared. The results of the bioassay show that amplification of the claR gene in multicopy plasmids resulted in a 2.5 fold increase in clavulanic acid production .   Discussion and conclusion : In this study the 3.3 fold increase in clavulanic acid production was obtained by using an expression vector containing claR. According to the clinical use of clavulanic acid, production of bacterial strains which are able to produce high level of antibiotic can help significantly in customization of antibiotic production.

  16. Gene Discovery for Synthetic Biology: Exploring the Novel Natural Product Biosynthetic Capacity of Eukaryotic Microalgae.

    Science.gov (United States)

    O'Neill, E C; Saalbach, G; Field, R A

    2016-01-01

    Eukaryotic microalgae are an incredibly diverse group of organisms whose sole unifying feature is their ability to photosynthesize. They are known for producing a range of potent toxins, which can build up during harmful algal blooms causing damage to ecosystems and fisheries. Genome sequencing is lagging behind in these organisms because of their genetic complexity, but transcriptome sequencing is beginning to make up for this deficit. As more sequence data becomes available, it is apparent that eukaryotic microalgae possess a range of complex natural product biosynthesis capabilities. Some of the genes concerned are responsible for the biosynthesis of known toxins, but there are many more for which we do not know the products. Bioinformatic and analytical techniques have been developed for natural product discovery in bacteria and these approaches can be used to extract information about the products synthesized by algae. Recent analyses suggest that eukaryotic microalgae produce many complex natural products that remain to be discovered.

  17. 1,3-Propanediol production by new recombinant Escherichia coli containing genes from pathogenic bacteria.

    Science.gov (United States)

    Przystałowska, Hanna; Zeyland, Joanna; Szymanowska-Powałowska, Daria; Szalata, Marlena; Słomski, Ryszard; Lipiński, Daniel

    2015-02-01

    1,3-Propanediol (1,3-PDO) is an organic compound, which is a valuable intermediate product, widely used as a monomer for synthesizing biodegradable polymers, increasing their strength; as well as an ingredient of textile, cosmetic and medical products. 1,3-PDO is mostly synthesized chemically. Global companies have developed technologies for 1,3-PDO synthesis from petroleum products such as acrolein and ethylene oxide. A potentially viable alternative is offered by biotechnological processes using microorganisms capable of synthesizing 1,3-PDO from renewable substrates (waste glycerol, a by-product of biofuel production, or glucose). In the present study, genes from Citrobacter freundii and Klebsiella pneumoniae were introduced into Escherichia coli bacteria to enable the synthesis of 1,3-PDO from waste glycerol. These strains belong to the best 1,3-PDO producers, but they are pathogenic, which restricts their application in industrial processes. The present study involved the construction of two gene expression constructs, containing a total of six heterologous glycerol catabolism pathway genes from C. freundii ATCC 8090 and K. pneumoniae ATCC 700721. Heterologous genes encoding glycerol dehydratase (dhaBCE) and the glycerol dehydratase reactivation factor (dhaF, dhaG) from C. freundii and gene encoding 1,3-PDO oxidoreductase (dhaT) from K. pneumoniae were expressed in E. coli under the control of the T7lac promoter. An RT-PCR analysis and overexpression confirmed that 1,3-PDO synthesis pathway genes were expressed on the RNA and protein levels. In batch fermentation, recombinant E. coli bacteria used 32.6gl(-1) of glycerol to produce 10.6 gl(-1) of 1,3-PDO, attaining the efficiency of 0.4 (mol₁,₃-PDO molglycerol(-1)). The recombinant E. coli created is capable of metabolizing glycerol to produce 1,3-PDO, and the efficiency achieved provides a significant research potential of the bacterium. In the face of shortage of fossil fuel supplies and climate warming

  18. Prevalence of Campylobacter species in milk and milk products, their virulence gene profile and antibiogram

    Directory of Open Access Journals (Sweden)

    Shivani Modi

    2015-01-01

    Full Text Available Aim: During the last decades, number of food poisoning cases due to Campylobacter occurred, immensely. After poultry, raw milk acts as a second main source of Campylobacter. Therefore, the present study was undertaken to detect the prevalence of Campylobacters in milk and milk products and to know the antibiotic sensitivity and virulence gene profile of Campylobacter spp. in Anand city, Gujarat, India. Materials and Methods: A total of 240 samples (85 buffalo milk, 65 cow milk, 30 cheese, 30 ice-cream and 30 paneer were collected from the different collection points in Anand city. The samples were processed by microbiological culture method, and presumptive isolates were further confirmed by genus and species-specific polymerase chain reaction using previously reported primer. The isolates were further subjected to antibiotic susceptibility assay and virulence gene detection. Result: Campylobacter species were detected in 7 (2.91% raw milk samples whereas none of the milk product was positive. All the isolate identified were Campylobacter jejuni. Most of the isolates showed resistance against nalidixic acid, ciprofloxacin, and tetracyclin. All the isolates have three virulence genes cadF, cdtB and flgR whereas only one isolate was positive for iamA gene and 6 isolates were positive for fla gene. Conclusion: The presence of Campylobacter in raw milk indicates that raw milk consumption is hazardous for human being and proper pasteurization of milk and adaptation of hygienic condition will be necessary to protect the consumer from this zoonotic pathogen.

  19. Decarboxylase gene expression and cadaverine and putrescine production by Serratia proteamaculans in vitro and in beef.

    Science.gov (United States)

    De Filippis, Francesca; Pennacchia, Carmela; Di Pasqua, Rosangela; Fiore, Alberto; Fogliano, Vincenzo; Villani, Francesco; Ercolini, Danilo

    2013-08-01

    Studies of the molecular basis of microbial metabolic activities that are important for the changes in food quality are valuable in order to help in understanding the behavior of spoiling bacteria in food. The growth of a psychrotrophic Serratia proteamaculans strain was monitored in vitro and in artificially inoculated raw beef. Two growth temperatures (25°C and 4°C) were tested in vitro, while growth at 15°C and 4°C was monitored in beef. During growth, the expression of inducible lysine and ornithine-decarboxylase genes was evaluated by quantitative reverse transcription-PCR (qRT-PCR), while the presence of cadaverine and putrescine was quantified by LC-ESI-MS/MS. The expression of the decarboxylase genes, and the consequent production of cadaverine and putrescine were shown to be influenced by the temperature, as well as by the complexity of the growth medium. Generally, the maximum gene expression and amine production took place during the exponential and early stationary phase, respectively. In addition, lower temperatures caused slower growth and gene downregulation. Higher amounts of cadaverine compared to putrescine were found during growth in beef with the highest concentrations corresponding to microbial loads of ca. 9CFU/g. The differences found in gene expression evaluated in vitro and in beef suggested that such activities are more reliably investigated in situ in specific food matrices.

  20. Dairy Product Consumption Interacts with Glucokinase (GCK Gene Polymorphisms Associated with Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Marine S. Da Silva

    2017-08-01

    Full Text Available Dairy product intake and a person’s genetic background have been reported to be associated with the risk of type 2 diabetes (T2D. The objective of this study was to examine the interaction between dairy products and genes related to T2D on glucose-insulin homeostasis parameters. A validated food frequency questionnaire, fasting blood samples, and glucokinase (GCK genotypes were analyzed in 210 healthy participants. An interaction between rs1799884 in GCK and dairy intake on the homeostasis model assessment of insulin resistance was identified. Secondly, human hepatocellular carcinoma cells (HepG2 were grown in a high-glucose medium and incubated with either 1-dairy proteins: whey, caseins, and a mixture of whey and casein; and 2-four amino acids (AA or mixtures of AA. The expression of GCK-related genes insulin receptor substrate-1 (IRS-1 and fatty acid synthase (FASN was increased with whey protein isolate or hydrolysate. Individually, leucine increased IRS-1 expression, whereas isoleucine and valine decreased FASN expression. A branched-chain AA mixture decreased IRS-1 and FASN expression. In conclusion, carriers of the A allele for rs1799884 in the GCK gene may benefit from a higher intake of dairy products to maintain optimal insulin sensitivity. Moreover, the results show that whey proteins affect the expression of genes related to glucose metabolism.

  1. A shortest-path graph kernel for estimating gene product semantic similarity

    Directory of Open Access Journals (Sweden)

    Alvarez Marco A

    2011-07-01

    Full Text Available Abstract Background Existing methods for calculating semantic similarity between gene products using the Gene Ontology (GO often rely on external resources, which are not part of the ontology. Consequently, changes in these external resources like biased term distribution caused by shifting of hot research topics, will affect the calculation of semantic similarity. One way to avoid this problem is to use semantic methods that are "intrinsic" to the ontology, i.e. independent of external knowledge. Results We present a shortest-path graph kernel (spgk method that relies exclusively on the GO and its structure. In spgk, a gene product is represented by an induced subgraph of the GO, which consists of all the GO terms annotating it. Then a shortest-path graph kernel is used to compute the similarity between two graphs. In a comprehensive evaluation using a benchmark dataset, spgk compares favorably with other methods that depend on external resources. Compared with simUI, a method that is also intrinsic to GO, spgk achieves slightly better results on the benchmark dataset. Statistical tests show that the improvement is significant when the resolution and EC similarity correlation coefficient are used to measure the performance, but is insignificant when the Pfam similarity correlation coefficient is used. Conclusions Spgk uses a graph kernel method in polynomial time to exploit the structure of the GO to calculate semantic similarity between gene products. It provides an alternative to both methods that use external resources and "intrinsic" methods with comparable performance.

  2. Enhanced hydrogen production by insertional inactivation of adhE gene in Klebsiella oxytoca HP1

    Institute of Scientific and Technical Information of China (English)

    ZHU JunBo; LONG MinNan; XU FangCheng; WU XiaoBing; XU HuiJuan

    2007-01-01

    Ethanol is the main byproduct of anaerobic H2-producing fermentation in Klebsiella oxytoca HP1. Two moles of NAD(P)H are consumed to yield one mole of ethanol that may decrease bacterial hydrogen production. In this article the adhE gene that codes for acetaldehyde dehydrogenase was disrupted for the first time. A homologous recombination vector pTA-Str was constructed in which the adhE gene was disrupted by inserting an aminoglycoside-3'-adenyltransferase (aadA) gene. As expected, the vector includes the insertion 5'-adhE-aadA-adhE-3'. The amplified DNA fragment 5'-adhE-aadA-adhE-3' from pTA-Str was transformed into K. Oxytoca HP1 and one recombinant was obtained. PCR analysis of the resulting genomic DNA indicated the appropriate deletion and insertion. Compared with the H2-production of wild type K. Oxytoca HP1, the hydrogen yield of the mutant increased by 16.07% and ethanol concentration decreased by 77.47%, suggesting that inactivation of the adhE gene in K. Oxytoca HP1 is a potential method for enhancing bacterial H2-production.

  3. Correlation of methane production and functional gene transcriptional activity in a peat soil.

    Science.gov (United States)

    Freitag, Thomas E; Prosser, James I

    2009-11-01

    The transcription dynamics of subunit A of the key gene in methanogenesis (methyl coenzyme M reductase; mcrA) was studied to evaluate the relationship between process rate (methanogenesis) and gene transcription dynamics in a peat soil ecosystem. Soil methanogen process rates were determined during incubation of peat slurries at temperatures from 4 to 37 degrees C, and real-time quantitative PCR was applied to quantify the abundances of mcrA genes and transcripts; corresponding transcriptional dynamics were calculated from mcrA transcript/gene ratios. Internal standards suggested unbiased recovery of mRNA abundances in comparison to DNA levels. In comparison to those in pure-culture studies, mcrA transcript/gene ratios indicated underestimation by 1 order of magnitude, possibly due to high proportions of inactive or dead methanogens. Methane production rates were temperature dependent, with maxima at 25 degrees C, but changes in abundance and transcription of the mcrA gene showed no correlation with temperature. However, mcrA transcript/gene ratios correlated weakly (regression coefficient = 0.76) with rates of methanogenesis. Methanogen process rates increased over 3 orders of magnitude, while the corresponding maximum transcript/gene ratio increase was only 18-fold. mcrA transcript dynamics suggested steady-state expression in peat soil after incubation for 24 and 48 h, similar to that in stationary-phase cultures. mcrA transcript/gene ratios are therefore potential in situ indicators of methanogen process rate changes in complex soil systems.

  4. New Insights about Antibiotic Production by Pseudomonas aeruginosa: A Gene Expression Analysis

    Directory of Open Access Journals (Sweden)

    Bárbara Gionco

    2017-09-01

    Full Text Available The bacterial resistance for antibiotics is one of the most important problems in public health and only a small number of new products are in development. Antagonistic microorganisms from soil are a promising source of new candidate molecules. Products of secondary metabolism confer adaptive advantages for their producer, in the competition for nutrients in the microbial community. The biosynthesis process of compounds with antibiotic activity is the key to optimize their production and the transcriptomic study of microorganisms is of great benefit for the discovery of these metabolic pathways. Pseudomonas aeruginosa LV strain growing in the presence of copper chloride produces a bioactive organometallic compound, which has a potent antimicrobial activity against various microorganisms. The objective of this study was to verify overexpressed genes and evaluate their relation to the organometallic biosynthesis in this microorganism. P. aeruginosa LV strain was cultured in presence and absence of copper chloride. Two methods were used for transcriptomic analysis, genome reference-guided assembly and de novo assembly. The genome referenced analysis identified nine upregulated genes when bacteria were exposed to copper chloride, while the De Novo Assembly identified 12 upregulated genes. Nineteen genes can be related to an increased microbial metabolism for the extrusion process of exceeding intracellular copper. Two important genes are related to the biosynthesis of phenazine and tetrapyrroles compounds, which can be involved in the bioremediation of intracellular copper and we suggesting that may involve in the biosynthesis of the organometallic compound. Additional studies are being carried out to further prove the function of the described genes and relate them to the biosynthetic pathway of the organometallic compound.

  5. Association of methionine synthase gene polymorphisms with wool production and quality traits in Chinese Merino population.

    Science.gov (United States)

    Rong, E G; Yang, H; Zhang, Z W; Wang, Z P; Yan, X H; Li, H; Wang, N

    2015-10-01

    Methionine synthase (MTR) plays a crucial role in maintaining homeostasis of intracellular methionine, folate, and homocysteine, and its activity correlates with DNA methylation in many mammalian tissues. Our previous genomewide association study identified that 1 SNP located in the gene was associated with several wool production and quality traits in Chinese Merino. To confirm the potential involvement of the gene in sheep wool production and quality traits, we performed sheep tissue expression profiling, SNP detection, and association analysis with sheep wool production and quality traits. The semiquantitative reverse transcription PCR analysis showed that the gene was differentially expressed in skin from Merino and Kazak sheep. The sequencing analysis identified a total of 13 SNP in the gene from Chinese Merino sheep. Comparison of the allele frequencies revealed that these 13 identified SNP were significantly different among the 6 tested Chinese Merino strains ( < 0.001). Linkage disequilibrium analysis showed that SNP 3 to 11 were strongly linked in a single haplotype block in the tested population. Association analysis showed that SNP 2 to 11 were significantly associated with the average wool fiber diameter and the fineness SD and that SNP 4 to 11 were significantly associated with the CV of fiber diameter trait ( < 0.05). Single nucleotide polymorphism 2 and SNP 5 to 12 were weakly associated with wool crimp. Similarly, the haplotypes derived from these 13 identified SNP were also significantly associated with the average wool fiber diameter, fineness SD, and the CV of fiber diameter ( < 0.05). Our results suggest that is a candidate gene for sheep wool production and quality traits, and the identified SNP might be used in sheep breeding.

  6. STAPHYLOCOCCUS AUREUS ISOLATES FROM CAMELS DIFFER IN COAGULASE PRODUCTION, GENOTYPE AND METHICILLIN RESISTANCE GENE PROFILES

    Directory of Open Access Journals (Sweden)

    Ziad Jaradat

    2013-06-01

    Full Text Available Accurate and rapid typing of S. aureus is crucial to the control of its infections and minimizing its leakage to the food chain. The primary purpose of this research was to isolate S. aureus from camels’ meat and nasal swabs and to characterize the isolates for coagulase production and the presence of methicillin gene using PCR-RFLP of coagulase gene. A total of 264 camel’s meat and nasal swabs were collected from abattoirs or meat markets and were used in the study. Ninety two percent of samples showed typical colonies of S. aureus on Baird-Parker agar with a mean count 2.5 × 104 ± 1.8 × 104 CFU g-1. Upon confirmation of the isolates using S. aureus specific thermonuclease gene (nuc PCR primers, only 64 isolates contained the specific product and thus were confirmed as S. aureus. However, when tested for the presence of coagulase gene, only 48 of them were positive while the other 16 were coagulase negative. Coagulase gene-RFLP revealed 19 distinct patterns when the gene was digested with Alu I and Cfo I. The typing revealed that the 48 classified isolates were genetically diverse and comprised a heterogeneous population with 14 genotypes at a 44.4% similarity level. When the coagulase positive isolates were tested for the presence of methicillin resistance (mec A gene, 37 of the isolates were positive while the other 11 isolates were negative. The high heterogeneity among S. aureus isolates might be due to cross contamination between camel carcasses in slaughter houses and from handlers and their utensils.

  7. Four gene products are required for the fungal synthesis of the indole-diterpene, paspaline.

    Science.gov (United States)

    Saikia, Sanjay; Parker, Emily J; Koulman, Albert; Scott, Barry

    2006-03-06

    Paspaline belongs to a large, structurally and functionally diverse group of indole-diterpenes synthesized by filamentous fungi. However, the identity of the gene products required for the biosynthesis of paspaline, a key intermediate for the synthesis of paxilline and other indole-diterpenes, is not known. Transfer of constructs containing different pax gene combinations into a paxilline negative deletion derivative of Penicillium paxilli demonstrated that just four proteins, PaxG, a geranylgeranyl diphosphate synthase, PaxM, a FAD-dependent monooxygenase, PaxB, a putative membrane protein, and PaxC, a prenyl transferase, are required for the biosynthesis of paspaline.

  8. Overproduction and purification of the luxR gene product: Transcriptional activator of the Vibrio fischeri luminescence system

    OpenAIRE

    1987-01-01

    Expression of Vibrio fischeri luminescence genes requires an inducer, termed autoinducer, and a positive regulatory element, the luxR gene product. A plasmid containing luxR under control of a tac promoter was engineered to overproduce this gene product. The overproduced luxR gene product was active in vivo, and its apparent monomeric molecular weight was indistinguishable from that of the protein encoded by luxR under control of its own promoter (Mr 27,000). The new tac-luxR construct direct...

  9. Glutamic acid promotes monacolin K production and monacolin K biosynthetic gene cluster expression in Monascus.

    Science.gov (United States)

    Zhang, Chan; Liang, Jian; Yang, Le; Chai, Shiyuan; Zhang, Chenxi; Sun, Baoguo; Wang, Chengtao

    2017-12-01

    This study investigated the effects of glutamic acid on production of monacolin K and expression of the monacolin K biosynthetic gene cluster. When Monascus M1 was grown in glutamic medium instead of in the original medium, monacolin K production increased from 48.4 to 215.4 mg l(-1), monacolin K production increased by 3.5 times. Glutamic acid enhanced monacolin K production by upregulating the expression of mokB-mokI; on day 8, the expression level of mokA tended to decrease by Reverse Transcription-polymerase Chain Reaction. Our findings demonstrated that mokA was not a key gene responsible for the quantity of monacolin K production in the presence of glutamic acid. Observation of Monascus mycelium morphology using Scanning Electron Microscope showed glutamic acid significantly increased the content of Monascus mycelium, altered the permeability of Monascus mycelium, enhanced secretion of monacolin K from the cell, and reduced the monacolin K content in Monascus mycelium, thereby enhancing monacolin K production.

  10. Epstein-Barr virus immediate-early gene product trans-activates gene expression from the human immunodeficiency virus long terminal repeat

    Energy Technology Data Exchange (ETDEWEB)

    Kenney, S.; Kamine, J.; Markovitz, D.; Fenrick, R.; Pagano, J.

    1988-03-01

    Acquired immunodeficiency syndrome patients are frequently coinfected with Epstein-Barr virus (EBV). In this report, the authors demonstrate that an EBV immediate-early gene product, BamHI MLF1, stimulates expression of the bacterial chloramphenicol acetyltransferase (CAT) gene linked to the human immunodeficiency virus (HIV) promoter. The HIV promoter sequences necessary for trans-activation by EBV do not include the tat-responsive sequences. In addition, in contrast to the other herpesvirus trans-activators previously studied, the EBV BamHI MLF1 gene product appears to function in part by a posttranscriptional mechanism, since it increases pHIV-CAT protein activity more than it increases HIV-CAT mRNA. This ability of an EBV gene product to activate HIV gene expression may have biologic consequences in persons coinfected with both viruses.

  11. Sequencing rare marine actinomycete genomes reveals high density of unique natural product biosynthetic gene clusters.

    Science.gov (United States)

    Schorn, Michelle A; Alanjary, Mohammad M; Aguinaldo, Kristen; Korobeynikov, Anton; Podell, Sheila; Patin, Nastassia; Lincecum, Tommie; Jensen, Paul R; Ziemert, Nadine; Moore, Bradley S

    2016-12-01

    Traditional natural product discovery methods have nearly exhausted the accessible diversity of microbial chemicals, making new sources and techniques paramount in the search for new molecules. Marine actinomycete bacteria have recently come into the spotlight as fruitful producers of structurally diverse secondary metabolites, and remain relatively untapped. In this study, we sequenced 21 marine-derived actinomycete strains, rarely studied for their secondary metabolite potential and under-represented in current genomic databases. We found that genome size and phylogeny were good predictors of biosynthetic gene cluster diversity, with larger genomes rivalling the well-known marine producers in the Streptomyces and Salinispora genera. Genomes in the Micrococcineae suborder, however, had consistently the lowest number of biosynthetic gene clusters. By networking individual gene clusters into gene cluster families, we were able to computationally estimate the degree of novelty each genus contributed to the current sequence databases. Based on the similarity measures between all actinobacteria in the Joint Genome Institute's Atlas of Biosynthetic gene Clusters database, rare marine genera show a high degree of novelty and diversity, with Corynebacterium, Gordonia, Nocardiopsis, Saccharomonospora and Pseudonocardia genera representing the highest gene cluster diversity. This research validates that rare marine actinomycetes are important candidates for exploration, as they are relatively unstudied, and their relatives are historically rich in secondary metabolites.

  12. Identification of Drosophila gene products required for phagocytosis of Candida albicans.

    Directory of Open Access Journals (Sweden)

    Shannon L Stroschein-Stevenson

    2006-01-01

    Full Text Available Phagocytosis is a highly conserved aspect of innate immunity. We used Drosophila melanogaster S2 cells as a model system to study the phagocytosis of Candida albicans, the major fungal pathogen of humans, by screening an RNAi library representing 7,216 fly genes conserved among metazoans. After rescreening the initial genes identified and eliminating certain classes of housekeeping genes, we identified 184 genes required for efficient phagocytosis of C. albicans. Diverse biological processes are represented, with actin cytoskeleton regulation, vesicle transport, signaling, and transcriptional regulation being prominent. Secondary screens using Escherichia coli and latex beads revealed several genes specific for C. albicans phagocytosis. Characterization of one of those gene products, Macroglobulin complement related (Mcr, shows that it is secreted, that it binds specifically to the surface of C. albicans, and that it promotes its subsequent phagocytosis. Mcr is closely related to the four Drosophila thioester proteins (Teps, and we show that TepII is required for efficient phagocytosis of E. coli (but not C. albicans or Staphylococcus aureus and that TepIII is required for the efficient phagocytosis of S. aureus (but not C. albicans or E. coli. Thus, this family of fly proteins distinguishes different pathogens for subsequent phagocytosis.

  13. Stable disruption of ethanol production by deletion of the genes encoding alcohol dehydrogenase isozymes in Saccharomyces cerevisiae.

    Science.gov (United States)

    Ida, Yoshihiro; Furusawa, Chikara; Hirasawa, Takashi; Shimizu, Hiroshi

    2012-02-01

    We analyzed the effects of the deletions of genes encoding alcohol dehydrogenase (ADH) isozymes of Saccharomyces cerevisiae. The decrease in ethanol production by ADH1 deletion alone could be partially compensated by the upregulation of other isozyme genes, while the deletion of all known ADH isozyme genes stably disrupted ethanol production. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  14. Re-examination of regulatory opinions in Europe: possible contribution for the approval of the first gene therapy product Glybera

    OpenAIRE

    2015-01-01

    The first commercially approved human gene therapy in the Western world is Glybera (alipogene tiparvovec), which is an adenoassociated viral vector encoding the lipoprotein lipase gene. Glybera was recommended for marketing authorization by the European Medicines Agency in 2012. The European Medicines Agency had only ever reviewed three marketing authorization applications for gene therapy medicinal products. Unlike in the case of Glybera, the applications of the first two products, Cerepro a...

  15. Synthesis of bacteriophage-coded gene products during infection of Escherichia coli with amber mutants of T3 and T7 defective in gene 1

    DEFF Research Database (Denmark)

    Issinger, O G; Hausmann, R

    1973-01-01

    During nonpermissive infection by a T7 amber mutant in gene 1 (phage RNA polymerase-deficient), synthesis of the products of the phage genes 3 (endonuclease), 3, 5 (lysozyme), 5 (DNA polymerase), and 17 (serum blocking power) was shown to occur at about half the rate as during wild-type infection...

  16. Yeast homologous recombination-based promoter engineering for the activation of silent natural product biosynthetic gene clusters.

    Science.gov (United States)

    Montiel, Daniel; Kang, Hahk-Soo; Chang, Fang-Yuan; Charlop-Powers, Zachary; Brady, Sean F

    2015-07-21

    Large-scale sequencing of prokaryotic (meta)genomic DNA suggests that most bacterial natural product gene clusters are not expressed under common laboratory culture conditions. Silent gene clusters represent a promising resource for natural product discovery and the development of a new generation of therapeutics. Unfortunately, the characterization of molecules encoded by these clusters is hampered owing to our inability to express these gene clusters in the laboratory. To address this bottleneck, we have developed a promoter-engineering platform to transcriptionally activate silent gene clusters in a model heterologous host. Our approach uses yeast homologous recombination, an auxotrophy complementation-based yeast selection system and sequence orthogonal promoter cassettes to exchange all native promoters in silent gene clusters with constitutively active promoters. As part of this platform, we constructed and validated a set of bidirectional promoter cassettes consisting of orthogonal promoter sequences, Streptomyces ribosome binding sites, and yeast selectable marker genes. Using these tools we demonstrate the ability to simultaneously insert multiple promoter cassettes into a gene cluster, thereby expediting the reengineering process. We apply this method to model active and silent gene clusters (rebeccamycin and tetarimycin) and to the silent, cryptic pseudogene-containing, environmental DNA-derived Lzr gene cluster. Complete promoter refactoring and targeted gene exchange in this "dead" cluster led to the discovery of potent indolotryptoline antiproliferative agents, lazarimides A and B. This potentially scalable and cost-effective promoter reengineering platform should streamline the discovery of natural products from silent natural product biosynthetic gene clusters.

  17. Disruption of ubiquitin-related genes in laboratory yeast strains enhances ethanol production during sake brewing.

    Science.gov (United States)

    Wu, Hong; Watanabe, Tomoko; Araki, Yoshio; Kitagaki, Hiroshi; Akao, Takeshi; Takagi, Hiroshi; Shimoi, Hitoshi

    2009-06-01

    Sake yeast can produce high levels of ethanol in concentrated rice mash. While both sake and laboratory yeast strains belong to the species Saccharomyces cerevisiae, the laboratory strains produce much less ethanol. This disparity in fermentation activity may be due to the strains' different responses to environmental stresses, including ethanol accumulation. To obtain more insight into the stress response of yeast cells under sake brewing conditions, we carried out small-scale sake brewing tests using laboratory yeast strains disrupted in specific stress-related genes. Surprisingly, yeast strains with disrupted ubiquitin-related genes produced more ethanol than the parental strain during sake brewing. The elevated fermentation ability conferred by disruption of the ubiquitin-coding gene UBI4 was confined to laboratory strains, and the ubi4 disruptant of a sake yeast strain did not demonstrate a comparable increase in ethanol production. These findings suggest different roles for ubiquitin in sake and laboratory yeast strains.

  18. The SKP1-like gene family of Arabidopsis exhibits a high degree of differential gene expression and gene product interaction during development.

    Directory of Open Access Journals (Sweden)

    Mohammad H Dezfulian

    Full Text Available The Arabidopsis thaliana genome encodes several families of polypeptides that are known or predicted to participate in the formation of the SCF-class of E3-ubiquitin ligase complexes. One such gene family encodes the Skp1-like class of polypeptide subunits, where 21 genes have been identified and are known to be expressed in Arabidopsis. Phylogenetic analysis based on deduced polypeptide sequence organizes the family of ASK proteins into 7 clades. The complexity of the ASK gene family, together with the close structural similarity among its members raises the prospect of significant functional redundancy among select paralogs. We have assessed the potential for functional redundancy within the ASK gene family by analyzing an expanded set of criteria that define redundancy with higher resolution. The criteria used include quantitative expression of locus-specific transcripts using qRT-PCR, assessment of the sub-cellular localization of individual ASK:YFP auto-fluorescent fusion proteins expressed in vivo as well as the in planta assessment of individual ASK-F-Box protein interactions using bimolecular fluorescent complementation techniques in combination with confocal imagery in live cells. The results indicate significant functional divergence of steady state transcript abundance and protein-protein interaction specificity involving ASK proteins in a pattern that is poorly predicted by sequence-based phylogeny. The information emerging from this and related studies will prove important for defining the functional intersection of expression, localization and gene product interaction that better predicts the formation of discrete SCF complexes, as a prelude to investigating their molecular mode of action.

  19. The SKP1-like gene family of Arabidopsis exhibits a high degree of differential gene expression and gene product interaction during development.

    Science.gov (United States)

    Dezfulian, Mohammad H; Soulliere, Danielle M; Dhaliwal, Rajdeep K; Sareen, Madhulika; Crosby, William L

    2012-01-01

    The Arabidopsis thaliana genome encodes several families of polypeptides that are known or predicted to participate in the formation of the SCF-class of E3-ubiquitin ligase complexes. One such gene family encodes the Skp1-like class of polypeptide subunits, where 21 genes have been identified and are known to be expressed in Arabidopsis. Phylogenetic analysis based on deduced polypeptide sequence organizes the family of ASK proteins into 7 clades. The complexity of the ASK gene family, together with the close structural similarity among its members raises the prospect of significant functional redundancy among select paralogs. We have assessed the potential for functional redundancy within the ASK gene family by analyzing an expanded set of criteria that define redundancy with higher resolution. The criteria used include quantitative expression of locus-specific transcripts using qRT-PCR, assessment of the sub-cellular localization of individual ASK:YFP auto-fluorescent fusion proteins expressed in vivo as well as the in planta assessment of individual ASK-F-Box protein interactions using bimolecular fluorescent complementation techniques in combination with confocal imagery in live cells. The results indicate significant functional divergence of steady state transcript abundance and protein-protein interaction specificity involving ASK proteins in a pattern that is poorly predicted by sequence-based phylogeny. The information emerging from this and related studies will prove important for defining the functional intersection of expression, localization and gene product interaction that better predicts the formation of discrete SCF complexes, as a prelude to investigating their molecular mode of action.

  20. The PKS4 gene in Fusarium graminearum is essential for zearalenone production

    DEFF Research Database (Denmark)

    Lysøe, E.; Klemsdal, S. S.; Bone, K.R.

    2006-01-01

    protocol was used to replace the central part of the PKS4 gene with a hygB resistance gene through double homologous recombination in an F. graminearum strain producing a high level of ZON. PCR and Southern analysis of transformants were used to identify isolates with single insertional replacements of PKS......4. High-performance liquid chromatography analysis showed that the PKS4 replacement mutant did not produce ZON. Thus, PKS4 encodes an enzyme required for the production of ZON in F. graminearum. Barley root infection studies revealed no alteration in the pathogenicity of the PKS4 mutant compared......-encoded protein or its product stimulates expression of PKS13. Furthermore, both the lack of aurofusarin and ZON influenced the expression of other polyketide synthases, demonstrating that one polyketide can influence the expression of others....

  1. Gene Disruption Technologies Have the Potential to Transform Stored Product Insect Pest Control

    Science.gov (United States)

    Perkin, Lindsey C.; Adrianos, Sherry L.; Oppert, Brenda

    2016-01-01

    Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, but is the most effective and economical control method, and thus is used extensively worldwide. However, many insect populations have become resistant to phosphine, in some cases to very high levels. New, environmentally benign and more effective control strategies are needed for stored product pests. RNA interference (RNAi) may overcome pesticide resistance by targeting the expression of genes that contribute to resistance in insects. Most data on RNAi in stored product insects is from the coleopteran genetic model, Tribolium castaneum, since it has a strong RNAi response via injection of double stranded RNA (dsRNA) in any life stage. Additionally, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology has been suggested as a potential resource for new pest control strategies. In this review we discuss background information on both gene disruption technologies and summarize the advances made in terms of molecular pest management in stored product insects, mainly T. castaneum, as well as complications and future needs. PMID:27657138

  2. Enterotoxin A Gene Barrier Staphylococcus aureus Within Traditionally Dairy Products of Tehran

    Directory of Open Access Journals (Sweden)

    Solmaz Hassani

    2014-11-01

    Full Text Available Background: Staphylococcus aureusis a serious agent that often colonize dairy products all over the world. Staphylococcal enterotoxins are the essential causes of food poisoningin human societies. Enterotoxin type A is an importantstaphylococcal exotoxin. Objectives: The aim of present study was to detect the enterotoxin producing Staphylococcus.aureus within different dairy products collected from Tehran, Iran. Materials and Methods: Two hundreds twenty dairy products samples were collected from local dealers across the city. The samples were first screened for S. aureus contaminations. All isolated strains of S. aureus were then investigated for enterotoxin a gene, usind spesific primer sets. Results: Staphylococcus aureus was isolated from 43% of dairy samples: 22% from milk and 18% from cheese samples. The SEA genes were detected in 10 isolates (22% originated from raw milk and in two isolates (25% from domestic cheese. Conclusions: Since, the staphylococcal enterotoxins are heat stable, heat had no effect on the toxicity of the enterotoxins within positive samples. Our primer stets confirmed previous studies that introduced PCR as rapid, sensitive, and specific method for dairy products screening system. Our data showed that routine screening and surveillance is vital for different food materials including dairy products.

  3. Gene Disruption Technologies Have the Potential to Transform Stored Product Insect Pest Control.

    Science.gov (United States)

    Perkin, Lindsey C; Adrianos, Sherry L; Oppert, Brenda

    2016-09-19

    Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, but is the most effective and economical control method, and thus is used extensively worldwide. However, many insect populations have become resistant to phosphine, in some cases to very high levels. New, environmentally benign and more effective control strategies are needed for stored product pests. RNA interference (RNAi) may overcome pesticide resistance by targeting the expression of genes that contribute to resistance in insects. Most data on RNAi in stored product insects is from the coleopteran genetic model, Tribolium castaneum, since it has a strong RNAi response via injection of double stranded RNA (dsRNA) in any life stage. Additionally, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology has been suggested as a potential resource for new pest control strategies. In this review we discuss background information on both gene disruption technologies and summarize the advances made in terms of molecular pest management in stored product insects, mainly T. castaneum, as well as complications and future needs.

  4. Gene Disruption Technologies Have the Potential to Transform Stored Product Insect Pest Control

    Directory of Open Access Journals (Sweden)

    Lindsey C. Perkin

    2016-09-01

    Full Text Available Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, but is the most effective and economical control method, and thus is used extensively worldwide. However, many insect populations have become resistant to phosphine, in some cases to very high levels. New, environmentally benign and more effective control strategies are needed for stored product pests. RNA interference (RNAi may overcome pesticide resistance by targeting the expression of genes that contribute to resistance in insects. Most data on RNAi in stored product insects is from the coleopteran genetic model, Tribolium castaneum, since it has a strong RNAi response via injection of double stranded RNA (dsRNA in any life stage. Additionally, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR technology has been suggested as a potential resource for new pest control strategies. In this review we discuss background information on both gene disruption technologies and summarize the advances made in terms of molecular pest management in stored product insects, mainly T. castaneum, as well as complications and future needs.

  5. Genome Wide Association Analysis Reveals New Production Trait Genes in a Male Duroc Population.

    Directory of Open Access Journals (Sweden)

    Kejun Wang

    Full Text Available In this study, 796 male Duroc pigs were used to identify genomic regions controlling growth traits. Three production traits were studied: food conversion ratio, days to 100 KG, and average daily gain, using a panel of 39,436 single nucleotide polymorphisms. In total, we detected 11 genome-wide and 162 chromosome-wide single nucleotide polymorphism trait associations. The Gene ontology analysis identified 14 candidate genes close to significant single nucleotide polymorphisms, with growth-related functions: six for days to 100 KG (WT1, FBXO3, DOCK7, PPP3CA, AGPAT9, and NKX6-1, seven for food conversion ratio (MAP2, TBX15, IVL, ARL15, CPS1, VWC2L, and VAV3, and one for average daily gain (COL27A1. Gene ontology analysis indicated that most of the candidate genes are involved in muscle, fat, bone or nervous system development, nutrient absorption, and metabolism, which are all either directly or indirectly related to growth traits in pigs. Additionally, we found four haplotype blocks composed of suggestive single nucleotide polymorphisms located in the growth trait-related quantitative trait loci and further narrowed down the ranges, the largest of which decreased by ~60 Mb. Hence, our results could be used to improve pig production traits by increasing the frequency of favorable alleles via artificial selection.

  6. Recombinant Streptomyces clavuligerus strain including cas2 gene production and analysis its antibiotic overproduction by bioassay

    Directory of Open Access Journals (Sweden)

    Zohreh Hojati

    2014-03-01

    Full Text Available Background: Streptomyces clavuligerus is one of the most important strain that produce clavulanic acid that wildly used in combination of strong but sensitive to β-lactamase antibiotics in clinics. The cas2 is one of the important genes in the biosynthesis pathway of clavulanic acid. Materials and Methods: The recombinant construct pMTcas2 which contain cas2 gene is obtained from Isfahan University. Recombinant plasmid extracts from streptomyces lividans and confirm by enzyme digestion. The streptomyces clavuligerus protoplast was prepared and transformation was done by using polyethylene glycol. Transformation was confirmed by plasmid extraction and PCR using cas2 specific primers. Finally, bioassay method was used to survey the effect of extra copy of cas2 on clavulanic acid production. Result: Plasmid extraction was initially carried out and the structure of plasmid was confirmed by digestion. The typical white colony was seen on protoplast recovery culture containing thiostrepton antibiotic and gray spores were detected after one week. Plasmid extraction was done from transformed strain and transformation was confirmed by PCR. The results of the bioassay show that amplification of the cas2 gene in multicopy plasmids resulted in a 4.1 fold increase in clavulanic acid production. Conclusion: The bioassay was done and the diameters of zone of inhibition in control and sample were compared. The results of the bioassay show that amplification of the cas2 gene in multicopy plasmids resulted in a 4.1 fold increase in clavulanic acid production. Overproduction of clavulanic acid decreases the cost of its dependent drug production.

  7. Expression of Clostridium acetobutylicum ATCC 824 Genes in Escherichia coli for Acetone Production and Acetate Detoxification

    OpenAIRE

    Bermejo, Lourdes L.; Welker, Neil E.; Papoutsakis, Eleftherios T.

    1998-01-01

    A synthetic acetone operon (ace4) composed of four Clostridium acetobutylicum ATCC 824 genes (adc, ctfAB, and thl, coding for the acetoacetate decarboxylase, coenzyme A transferase, and thiolase, respectively) under the control of the thl promoter was constructed and was introduced into Escherichia coli on vector pACT. Acetone production demonstrated that ace4 is expressed in E. coli and resulted in the reduction of acetic acid levels in the fermentation broth. Since different E. coli strains...

  8. Increasing cocoa butter-like lipid production of Saccharomyces cerevisiae by expression of selected cocoa genes.

    Science.gov (United States)

    Wei, Yongjun; Gossing, Michael; Bergenholm, David; Siewers, Verena; Nielsen, Jens

    2017-12-01

    Cocoa butter (CB) extracted from cocoa beans mainly consists of three different kinds of triacylglycerols (TAGs), 1,3-dipalmitoyl-2-oleoyl-glycerol (POP, C16:0-C18:1-C16:0), 1-palmitoyl-3-stearoyl-2-oleoyl-glycerol (POS, C16:0-C18:1-C18:0) and 1,3-distearoyl-2-oleoyl-glycerol (SOS, C18:0-C18:1-C18:0), but CB supply is limited. Therefore, CB-like lipids (CBL, which are composed of POP, POS and SOS) are in great demand. Saccharomyces cerevisiae produces TAGs as storage lipids, which are also mainly composed of C16 and C18 fatty acids. However, POP, POS and SOS are not among the major TAG forms in yeast. TAG synthesis is mainly catalyzed by three enzymes: glycerol-3-phosphate acyltransferase (GPAT), lysophospholipid acyltransferase (LPAT) and diacylglycerol acyltransferase (DGAT). In order to produce CBL in S. cerevisiae, we selected six cocoa genes encoding GPAT, LPAT and DGAT potentially responsible for CB biosynthesis from the cocoa genome using a phylogenetic analysis approach. By expressing the selected cocoa genes in S. cerevisiae, we successfully increased total fatty acid production, TAG production and CBL production in some S. cerevisiae strains. The relative CBL content in three yeast strains harboring cocoa genes increased 190, 230 and 196% over the control strain, respectively; especially, the potential SOS content of the three yeast strains increased 254, 476 and 354% over the control strain. Moreover, one of the three yeast strains had a 2.25-fold increased TAG content and 6.7-fold higher level of CBL compared with the control strain. In summary, CBL production by S. cerevisiae were increased through expressing selected cocoa genes potentially involved in CB biosynthesis.

  9. Genetic resources for methane production from biomass described with gene ontology

    Directory of Open Access Journals (Sweden)

    Endang ePurwantini

    2014-12-01

    Full Text Available Methane (CH4 is a valuable fuel, constituting 70-95% of natural gas, and a potent greenhouse gas. Release of CH4 into the atmosphere contributes to climate change. Biological CH4 production or methanogenesis is mostly performed by methanogens, a group of strictly anaerobic archaea. The direct substrates for methanogenesis are H2 plus CO2, acetate, formate, methylamines, methanol, methyl sulfides, and ethanol or a secondary alcohol plus CO2. In numerous anaerobic niches in nature, methanogenesis facilitates mineralization of complex biopolymers such as carbohydrates, lipids and proteins generated by primary producers. Thus, methanogens are critical players in the global carbon cycle. The same process is used in anaerobic treatment of municipal, industrial and agricultural wastes, reducing the biological pollutants in the wastes and generating methane. It also holds potential for commercial production of natural gas from renewable resources. This process operates in digestive systems of many animals, including cattle, and humans. In contrast, in deep-sea hydrothermal vents methanogenesis is a primary production process, allowing chemosynthesis of biomaterials from H2 plus CO2. In this report we present Gene Ontology (GO terms that can be used to describe processes, functions and cellular components involved in methanogenic biodegradation and biosynthesis of specialized coenzymes that methanogens use. Some of these GO terms were previously available and the rest were generated in our Microbial Energy Gene Ontology (MENGO project. A recently discovered non-canonical CH4 production process is also described. We have performed manual GO annotation of selected methanogenesis genes, based on experimental evidence, providing gold standards for machine annotation and automated discovery of methanogenesis genes or systems in diverse genomes. Most of the GO-related information presented in this report is available at the MENGO website (http://www.mengo.biochem.vt.edu/.

  10. Recombinant hepatitis B surface antigen production in Aspergillus niger: evaluating the strategy of gene fusion to native glucoamylase

    CSIR Research Space (South Africa)

    James, ER

    2012-10-01

    Full Text Available Microbiology and Biotechnology October 2012/ Vol. 96, No.2 Recombinant hepatitis B surface antigen production in Aspergillus niger: evaluating the strategy of gene fusion to native glucoamylase ER James a,c & WH van Zyl b & PJ van Zyl c & JF Görgens..., Pretoria 0001, South Africa Abstract This study demonstrates the potential of Aspergillus niger as a candidate expression system for virus- like particle production using gene fusion. Hepatitis B surface antigen (HBsAg) production, targeted...

  11. Characterization of the Expression of Basigin Gene Products Within the Pineal Gland of Mice.

    Science.gov (United States)

    Tokar, Derek; van Ekeris, Leslie; Linser, Paul J; Ochrietor, Judith D

    2016-11-04

    The expression of Basigin gene products and monocarboxylate transporter-1 (MCT1) has been investigated within the mammalian neural retina and suggests a role for these proteins in cellular metabolism within that tissue. The purpose of the present study was to investigate the expression of these same proteins in the pineal gland of the mouse brain. Mouse pineal gland and neural retina RNA and protein were subjected to quantitative reverse transcription-polymerase chain reaction and immunoblotting analyses. In addition, paraffin-embedded sections of each tissue were analyzed for expression of Basigin gene products and MCT1 via immunohistochemistry. The results indicate that MCT1 and Basigin variant-2, but not Basigin variant-1, are expressed within the mouse pineal gland. The expression of Basigin variant-2 and MCT1 was localized to the capsule surrounding the gland. The position and relative amounts of the gene products suggest that they play a much less prominent role within the pineal gland than in the neural retina.

  12. Diversity of Streptococcus thermophilus in bacteriocin production; inhibitory spectrum and occurrence of thermophilin genes.

    Science.gov (United States)

    Rossi, Franca; Marzotto, Marta; Cremonese, Silvia; Rizzotti, Lucia; Torriani, Sandra

    2013-08-01

    The bacteriocin-producing Streptococcus thermophilus strains that can dominate in natural dairy ecosystems, may also enhance safety in products obtained from natural cultures. In this study, we sought to identify bacteriocin production and bacteriocin genes in 75 strains of dairy and plant origin. The strains were tested for antimicrobial activity against pathogens or pathogen models, spoiling bacteria, and lactic acid bacteria associated with dairy products. All strains moderately inhibited Staphylococcus aureus P310, none inhibited Listeria innocua LMG 11387(T) or Clostridium tyrobutyricum LMG 1285(T). In addition, 14 were active against one or more indicators in addition to S. aureus P310. Inhibition of other starter bacteria was more common than the inhibition of unwanted microorganisms. The involvement of a proteinaceous compound was ascertained in all cases. Results suggested that the selection of bacteriocinogenic S. thermophilus strains for use in biopreservation must take into account the effects exerted on other lactic acid bacteria. PCR detection of thermophilin genes proved unreliable in predicting antimicrobial activity. For S. thermophilus PRI36 and PRI45, with relevant inhibitory features, the identity of the bacteriocin genes present in the thermophilin 9 cluster was defined, thus revealing novel variants for this genome region.

  13. Association of polymorphisms of Nrampl gene with immune function and production performance of large white pig

    Institute of Scientific and Technical Information of China (English)

    Hongmei Wu; Duxue Cheng; Lixian Wang

    2008-01-01

    The present research was designed to study the association of polymorphism of natural resistance-associated macrophage protein 1 (Nrampl) with some immune function and the production performance in Large White pig. The PCR-RFLP technique was applied to analyze the correlation between the polymorphisms of Nrampl gene and immune function [value of Polymorphonuclear Leukocytes (PMN) obtained by Nitroblue Tetrazolium (NBT) Reduction and effect of Cytotoxin in Monocyte] and production performance in 165 Large White pigs. The results showed that there was one Nde I restriction locus in Large White pig, and both values of PMN by NBT Reduction and effect of Cytotoxin in Monocyte in genotype BB were higher than those in genotype AB (P<0.05). Simultaneously, the weight of 180-day-old pigs with genotype BB was higher than that with genotype AB (.P<0.05). The results indicated that there was a significant correlation between different genotypes of Nrampl gene and Immune function and production performance, and it can be re garded as a candidate gene of disease resistance. All these results provide valuable reference to further studies of pig disease resistance.

  14. Differential carotenoid production and gene expression in Xanthophyllomyces dendrorhous grown in a nonfermentable carbon source.

    Science.gov (United States)

    Wozniak, Aniela; Lozano, Carla; Barahona, Salvador; Niklitschek, Mauricio; Marcoleta, Andrés; Alcaíno, Jennifer; Sepulveda, Dionisia; Baeza, Marcelo; Cifuentes, Víctor

    2011-05-01

    Xanthophyllomyces dendrorhous is a basidiomycetous yeast of considerable biotechnological interest because it synthesizes astaxanthin as its main carotenoid. The carotenoid production increases when it is grown using nonfermentable compounds as the sole carbon source. This work analyzes the expression of the carotenogenic genes and their relationship with the amount and types of carotenoids produced when X. dendrorhous is grown using a nonfermentable (succinate) or a fermentable carbon source (glucose). When X. dendrorhous is grown in succinate, carotenoid production is approximately three times higher than when it is grown in glucose. Moreover, carotenoid biosynthesis occurs at the start of the growth cycle when X. dendrorhous is grown in succinate, whereas when it is grown in glucose, carotenoids are produced at the end of the exponential phase. Additionally, we observed that some carotenogenic genes, such as alternative transcripts of crtYB and crtI, are differentially expressed when the yeast is grown in these carbon sources; other genes, such as crtS, exhibit a similar pattern of expression. Our data indicate that transcriptional regulation is not sufficient to explain the differences in carotenoid production between the two culture conditions, indicating that additional regulatory mechanisms may be operating in the carotenogenic pathway of X. dendrorhous.

  15. Functional cooperation of the dnaE and dnaN gene products in Escherichia coli.

    Science.gov (United States)

    Kuwabara, N; Uchida, H

    1981-09-01

    A system was designed to isolate second-site intergenic suppressors of a thermosensitive mutation of the dnaE gene of Escherichia coli. The dnaE gene codes for the alpha subunit of DNA polymerase III [McHenry, C. S. & Crow, W. (1979) J. Biol. Chem. 254, 1748-1753]. One such suppressor, named sueA77, was finely mapped and found to be located at 82 min on the E. coli chromosome, between dnaA and recF, and within the dnaN gene [Sakakibara, Y. & Mizukami, T. (1980) Mol. Gen. Genet. 178, 541-553]. The dnaN gene codes for the beta subunit of DNA polymerase III holoenzyme [Burgers, P. M. J., Kornberg, A. & Sakakibara, Y. (1981) Proc. Natl. Acad. Sci. USA 78, 5391-5395]. The sueA77 mutation was trans-dominant over its wild-type allele, and it suppressed different thermosensitive mutations of dnaE with different maximal permissive temperature. These properties were interpreted as providing genetic evidence for interaction of the dnaE and dnaN gene products in E. coli.

  16. Characterization of Toxin Genes and Antimicrobial Susceptibility of Staphylococcus aureus Isolates in Fishery Products in Iran

    Science.gov (United States)

    Arfatahery, Noushin; Davoodabadi, Abolfazl; Abedimohtasab, Taranehpeimaneh

    2016-01-01

    Staphylococcus aureus is one of the most common causes of seafood-borne diseases worldwide, which are attributable to the contamination of food by preformed enterotoxins. In this study, a total of 206 (34.3%) Staphylococcus aureus strains were obtained from 600 fish and shrimp samples and were tested for their antimicrobial susceptibility. We assessed the prevalence of the genes responsible for the staphylococcal enterotoxins (SEA, SEB) and toxic shock syndrome toxin 1 (TSST-1) genes. The results indicated that 34% of aqua food samples were contaminated with S. aureus, and 23.8% of these isolates were mec-A-positive. Sixty-four percent of the strains isolated from contaminated seafood was enterotoxigenic S. aureus, and 28.2% of SEs were MRSA-positive. The most prevalent genotype was characterized by the presence of the sea gene (45.2%), followed by the seb gene (18.5%), and the tst gene encoding TSST-1 was found in eight strains (3.9%). Of the 206 S. aureus isolates, 189 strains (84.9%) were resistant to at least one antibiotic. Given the frequent outbreaks of enterotoxigenic MRSA, it is necessary to make revisions to mandatory programmes to facilitate improved hygiene practices during fishing, aquaculture, processing, and sales to prevent the contamination of fishery products in Iran. PMID:27694813

  17. Production of transgenic mice by random recombination of targeted genes in female germline stem cells

    Institute of Scientific and Technical Information of China (English)

    Yong Zhang; Ji Xiong; Jie Xiang; Ji Wu; Zhaojuan Yang; Yunze Yang; Shuzeng Wang; Lingjun Shi; Wenhai Xie; Kejing Sun; Kang Zou; Lei Wang

    2011-01-01

    Oocyte production in most mammalian species is believed to cease before birth. However, this idea has been challenged with the finding that postnatal mouse ovaries possess mitotically active germ cells. A recent study showed that female germline stem cells (FGSCs) from adult mice were isolated, cultured long term and produced oocytes and progeny after transplantation into infertile mice. Here, we demonstrate the successful generation of transgenic or gene knock-down mice using FGSCs. The FGSCs from ovaries of 5-day-old and adult mice were isolated and either infected with recombinant viruses carrying green fluorescent protein, Oocyte-G1 or the mouse dynein axonemal intermediate chain 2 gene, or transfected with the Oocyte-G1 specific shRNA expression vector (pRS shOocyte-G1 vector), and then transplanted into infertile mice. Transplanted cells in the ovaries underwent oogenesis and produced heterozygous offspring after mating with wild-type male mice. The offspring were genetically characterized and the biological functions of the transferred or knock-down genes were investigated. Efficiency of genetransfer or gene knock-down was 29%-37% and it took 2 months to produce transgenic offspring. Gene manipulation of FGSCs is a rapid and efficient method of animal transgenesis and may serve as a powerful tool for biomedical science and biotechnology.

  18. Association between the enterotoxin production and presence of Coa, Nuc genes among Staphylococcus aureus isolated from various sources, in Shiraz.

    Science.gov (United States)

    Moghassem Hamidi, R; Hosseinzadeh, S; Shekarforoush, S S; Poormontaseri, M; Derakhshandeh, A

    2015-01-01

    The present study was aimed to identify the frequency of coagulase (Coa) and thermonuclease (Nuc) genes and Staphylococcal enterotoxin A (Sea) production among Staphylococcus aureus isolated from various sources in Shiraz. Moreover, the correlation between the Sea gene and coagulase and thermonuclease enzymes is also considered. A total of 100 S. aureus were isolated from various sources including 40 humans, 30 animals and 30 food samples by the routine biochemical tests. The frequency of Coa, Nuc and Sea genes was evaluated by PCR assay. Correlation among those genes was finally evaluated by statistical analysis. The PCR results showed that the prevalence of Coa, Nuc and Sea genes was 91%, 100% and 14%, respectively. The evaluation of the enterotoxin production indicated that 78.6% of the Sea gene was expressed. The presence of enterotoxin A was not necessarily correlated to the production of toxin. As a final conclusion to detect the enterotoxigenic strains, both genotypic and phenotypic methods are highly recommended.

  19. Engineering cell lines for production of replication defective HSV-1 gene therapy vectors.

    Science.gov (United States)

    Grant, Kyle G; Krisky, David M; Ataai, Mohammed M; Glorioso, Joseph C

    2009-03-01

    Herpes simplex virus type 1 (HSV-1) represents an attractive vehicle for a variety of gene therapy applications. To render this virus safe for clinical use, its cytotoxic genes must be removed without losing its ability to express transgenes efficiently. Our vectors are deleted for the essential immediate early genes ICP4 and ICP27. These genes are controlled by unique promoters having enhancer elements responsive to a viral structural protein VP16. The expression of these genes occurs prior to the activation of all other lytic functions and is thus required to initiate and complete the virus replication cycle. For large scale manufacture of clinical grade vectors, efficient cell lines must be generated that express the essential viral gene products in trans during vector propagation. Here we describe methods for engineering HSV-1 production cell lines that improve vector growth by altering the kinetics of complementing gene expression. We examined the ability of Vero cells independently transduced with ICP4 and ICP27 under transcriptional control of their respective promoters to support the growth of a replication defective vector (JDTOZHE), deleted for ICP4, ICP27 and approximately 20 kb of internal elements that are not required for virus growth in Vero cells. Vector yield on this cell line was 3 logs lower than wild-type virus grown on Vero cells. To understand the mechanism underlying poor vector yield, we examined the expression of ICP4 and ICP27 during virus complementation. While ICP27 was expressed immediately on vector infection, the expression of ICP4 was considerably delayed by 8-10 h, suggesting that the ICP4 promoter was not adequately activated by VP16 delivered by the infectious vector particle. Use of the ICP0 promoter to express ICP4 from the cellular genome resulted in higher induction levels and faster kinetics of ICP4 expression and a 10-fold improvement in vector yield. This study suggests that vector complementation is highly dependent on the

  20. Tetracycline residues and tetracycline resistance genes in groundwater impacted by swine production facilities

    Science.gov (United States)

    Mackie, R.I.; Koike, S.; Krapac, I.; Chee-Sanford, J.; Maxwell, Susan; Aminov, R.I.

    2006-01-01

    Antibiotics are used at therapeutic levels to treat disease; at slightly lower levels as prophylactics; and at low, subtherapeutic levels for growth promotion and improvement of feed efficiency. Over 88% of swine producers in the United States gave antimicrobials to grower/finisher pigs in feed as a growth promoter in 2000. It is estimated that ca. 75% of antibiotics are not absorbed by animals and are excreted in urine and feces. The extensive use of antibiotics in swine production has resulted in antibiotic resistance in many intestinal bacteria, which are also excreted in swine feces, resulting in dissemination of resistance genes into the environment.To assess the impact of manure management on groundwater quality, groundwater samples have been collected near two swine confinement facilities that use lagoons for manure storage and treatment. Several key contaminant indicators-including inorganic ions, antibiotics, and antibiotic resistance genes-were analyzed in groundwater collected from the monitoring wells. Chloride, ammonium, potassium, and sodium were predominant inorganic constituents in the manure samples and served as indicators of groundwater contamination. Based on these analyses, shallow groundwater has been impacted by lagoon seepage at both sites. Liquid chromatography-mass spectroscopy (LC-MS) was used to measure the dissolved concentrations of tetracycline, chlortetracycline, and oxytetracycline in groundwater and manure. Although tetracyclines were regularly used at both facilities, they were infrequently detected in manure samples and then at relatively trace concentrations. Concentrations of all tetracyclines and their breakdown products in the groundwater sampled were generally less than 0.5 ??g/L.Bacterial tetracycline resistance genes served as distinct genotypic markers to indicate the dissemination and mobility of antibiotic resistance genes that originated from the lagoons. Applying PCR to genomic DNA extracted from the lagoon and

  1. Alginate production and alg8 gene expression by Azotobacter vinelandii in continuous cultures.

    Science.gov (United States)

    Díaz-Barrera, Alvaro; Soto, Erik; Altamirano, Claudia

    2012-04-01

    Alginates are polysaccharides that are used as thickening agents, stabilizers, and emulsifiers in various industries. These biopolymers are produced by fermentation with a limited understanding of the processes occurring at the cellular level. The objective of this study was to evaluate the effects of agitation rate and inlet sucrose concentrations (ISC) on alginate production and the expression of the genes encoding for alginate-lyases (algL) and the catalytic subunit of the alginate polymerase complex (alg8) in chemostat cultures of Azotobacter vinelandii ATCC 9046. Increased alginate production (2.4 g l⁻¹) and a higher specific alginate production rate (0.1 g g⁻¹ h⁻¹) were obtained at an ISC of 15 g l⁻¹. Carbon recovery of about 100% was obtained at an ISC of 10 g l⁻¹, whereas it was close to 50% at higher ISCs, suggesting that cells growing at lower sucrose feed rates utilize the carbon source more efficiently. In each of the steady states evaluated, an increase in algL gene expression was not related to a decrease in alginate molecular weight, whereas an increase in the molecular weight of alginate was linked to higher alg8 gene expression, demonstrating a relationship between the alg8 gene and alginate polymerization in A. vinelandii for the first time. The results obtained provide a possible explanation for changes observed in the molecular weight of alginate synthesized and this knowledge can be used to build a recombinant strain able to overexpress alg8 in order to produce alginates with higher molecular weights.

  2. Relationships of growth hormone gene and milk protein polymorphisms to milk production traits in Simmental cattle.

    Science.gov (United States)

    Falaki, M; Prandi, A; Corradini, C; Sneyers, M; Gengler, N; Massart, S; Fazzini, U; Burny, A; Portetelle, D; Renaville, R

    1997-02-01

    The importance of milk proteins and the positive effect of administration of growth hormone (GH) on milk production, and the presence in some dairy cattle lines of greater GH concentrations prompted us to examine the presence of restriction fragment length polymorphism at the GH gene using the restriction enzyme TaqI and to investigate associations between this polymorphism in Simmental cows and bulls, as well as milk protein variants in Simmental cows, and milk production traits. Blood and milk were sampled from 279 Italian Simmental cows and semen was collected from 148 bulls of the same breed. Two fragment bands, denoted A and B, of 6200 and 5200 bp respectively, were examined and three patterns, AA, AB and BB, were found in both animal samples. All variants previously reported in other studies, for kappa, beta, and alpha s1-caseins, and beta-lactoglobulin, were found in the cows' samples. For the cows' samples, a BLUP (Best Linear Unbiased Predictor) analysis of results was performed using a REML (Restricted Maximum Likelihood) program and known heritabilities, whereas for bulls we have performed a General Linear Model analysis. The effect of GH gene polymorphism, using TaqI restriction enzyme, on milk production traits was not significant, but bulls of BB pattern had a higher breeding value for milk yield than AA bulls (P casein genotypic effects, cows of AB genotype gave milk with 1.53 +/- 0.70 g/kg less fat than cows of AA genotype. In addition, breeding values for milk protein content were significantly higher in BB bulls, with 0.87 +/- 0.32 and 0.71 +/- 0.34 g/kg more milk protein than AA and AB bulls respectively. Thus, our results revealed a GH gene polymorphism and indicated significant effects of milk protein polymorphisms on milk production traits in the Italian Simmental breed.

  3. Prevalence of ten putative virulence genes in the emerging foodborne pathogen Arcobacter isolated from food products.

    Science.gov (United States)

    Girbau, Cecilia; Guerra, Cristian; Martínez-Malaxetxebarria, Irati; Alonso, Rodrigo; Fernández-Astorga, Aurora

    2015-12-01

    Arcobacter spp. are considered to be emerging food- and waterborne pathogens for both humans and animals. However, their virulence mechanisms are still poorly understood. In this study the presence of ten virulence genes (cadF, ciaB, cj1349, hecA, hecB, mviN, pldA, irgA, tlyA and iroE) was assessed in a set of 47 strains of Arcobacter butzleri, 10 of Arcobacter cryaerophilus and 1 Arcobacter skirrowii strain recovered from different food products (pork, chicken, beef, milk, clams and mussels). Overall, the genes cadF, ciaB, cj1349, mviN, pldA and tlyA were detected in all A. butzleri and A. skirrowii strains. Lower detection rates were observed for irgA, iroE, hecA and hecB. The genes hecB and iroE were detected neither in A. cryaerophilus nor in A. skirrowii. The genes hecA and irgA were not detected in A. skirrowii. It was noteworthy that the genes hecA and hecB were significantly (P < 0.05) highly detected in A. butzleri strains isolated from clams compared with strains isolated from milk and chicken. Therefore, our findings underline clams as a source of A. butzleri strains with high prevalence of putative virulence genes. This could be hazardous to human health, especially because these bivalves are usually consumed raw or undercooked.

  4. POLYMORPHISM IN PROMOTER OF PROLACTIN GENE AND ITS ASSOCIATION WITH PRODUCTION TRAITS IN CHICKENS

    Directory of Open Access Journals (Sweden)

    Mitrofanova O. V.

    2015-09-01

    Full Text Available Prolactin (PRL - is a peptide hormone. It effects on metabolic processes in mammals and birds. Indel genotype mutations in a prolactin gene were determined in 595 hens and cocks. Polymerase chain reaction (PCR were used. We studied four different breeds: Cornish, White Russian, Pushkin, Yurlov crower. Homozygous of insertion II, homozygous deletion of DD and heterozygous ID were observed in all groups. The differences in frequencies of genotypes and alleles were observed in all groups. Homozygotes II and allele I (frequency is 0,83 were the most common for Russian white chickens with high egg production and the lack of the instinct of incubation. Prolactin gene deletion was more common for beef Cornish. The frequency of D allele was 0,84. Pushkin chickens proved to be closer to the egg type. A significant number of heterozygotes with this mutation were noted in a population of Yurlov crower. It is recommended to use gene prolactin as a marker of productive indicators in chickens

  5. Lessons in Détente or know thy host: The immunomodulatory gene products of myxoma virus

    Indian Academy of Sciences (India)

    Martha C Zúñiga

    2003-04-01

    The poxvirus, myxoma virus, encodes within its genome at least eleven different proteins that compromise, skew, or disable the innate and adaptive responses of its hosts. In the laboratory rabbit, Oryctolagus cuniculus, these effects result in myxomatosis, a fatal condition characterized by skin lesions and systemic immunosuppression. Interestingly, while myxoma infection also causes skin lesions in its natural host and in natural populations of O. cuniculus in Australia where this novel host and the virus have co-evolved, the condition of myxomatosis does not ensue and infection is not fatal. In this review I discuss the biochemical properties of the characterized immunomodulatory proteins of myxoma virus, and their pathogenic effects in laboratory rabbits. Disruption of any one myxoma immunomodulatory gene diminishes the severity of the infection without compromising infectivity. Thus, the characterized immunomodulatory genes appear not to be required for a productive infection in vivo. The differences in the severity of their effects in laboratory-bred versus wild O. cuniculus suggest that the outcome of myxoma infection is a consequence of the interplay between the viral immunomodulatory gene products and the cells and molecules of the host immune system.

  6. Metabolic engineering of Escherichia coli for ethanol production without foreign genes

    Science.gov (United States)

    Kim, Youngnyun

    Worldwide dependence on finite petroleum-based energy necessitates alternative energy sources that can be produced from renewable resources. A successful example of an alternative transportation fuel is bioethanol, produced by microorganisms, from corn starch that is blended with gasoline. However, corn, currently the main feedstock for bioethanol production, also occupies a significant role in human food and animal feed chains. As more corn is diverted to bioethanol, the cost of corn is expected to increase with an increase in the price of food, feed and ethanol. Using lignocellulosic biomass for ethanol production is considered to resolve this problem. However, this requires a microbial biocatalyst that can ferment hexoses and pentoses to ethanol. Escherichia coli is an efficient biocatalyst that can use all the monomeric sugars in lignocellulose, and recombinant derivatives of E. coli have been engineered to produce ethanol as the major fermentation product. In my study, ethanologenic E. coli strains were isolated from a ldhA-, pflB- derivative without introduction of foreign genes. These isolates grew anaerobically and produced ethanol as the main fermentation product. The mutation responsible for anaerobic growth and ethanol production was mapped in the lpdA gene and the mutation was identified as E354K in three of the isolates tested. Another three isolates carried an lpdA mutation, H352Y. Enzyme kinetic studies revealed that the mutated form of the dihydrolipoamide dehydrogenase (LPD) encoded by the lpdA was significantly less sensitive to NADH inhibition than the native LPD. This reduced NADH sensitivity of the mutated LPD was translated into lower sensitivity to NADH of the pyruvate dehydrogenase complex in strain SE2378. The net yield of 4 moles of NADH and 2 moles of acetyl-CoA per mole of glucose produced by a combination of glycolysis and PDH provided a logical basis to explain the production of 2 moles of ethanol per glucose. The development of E

  7. Multiple chromosomal gene integration for production of pharmaceutical proteins in S. cerevisiae

    DEFF Research Database (Denmark)

    Jensen, Malene; Mortensen, Uffe Hasbro; Gunnarsson, Nina

    2014-01-01

    When studying protein folding and secretion the general conception is that all cells in a population express an equal amount of protein. Recent work has shown that expression levels vary greatly in cell populations which express proteins on plasmids. Hence a yeast expression platform has been dev....... An amplification method has been developed for the platform which enables fast integration of genes. Future perspectives involve exploring the capabilities of the platform for recombinant protein production including performance and stability studies....... but the largest fraction of cells is actually not expressing either of the proteins. The yeast expression platform is developed to facilitate stable expression of integrated genes. The integration sites are separated by essential genes which ensure that the integrated genes are not lost by recombination......When studying protein folding and secretion the general conception is that all cells in a population express an equal amount of protein. Recent work has shown that expression levels vary greatly in cell populations which express proteins on plasmids. Hence a yeast expression platform has been...

  8. Bovine kappa-casein gene polymorphism and its association with milk production traits

    Directory of Open Access Journals (Sweden)

    Satyanarayana Rachagani

    2008-12-01

    Full Text Available Point mutations in exon IV of the bovine κ-casein (CSN3 gene determine two allelic variants, A and B. These variants were distinguished by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP analysis in the indigenous Sahiwal and Tharparkar cattle breeds. DNA samples (252 Sahiwal and 56 Tharparkar were analyzed for allelic variants of the CSN3 gene. Polymorphism was detected by digestion of PCR-amplified products with HindIII, HhaI and HaeIII restriction enzymes, followed by separation on 3% agarose gels, and resolved by ethidium bromide staining. Allele A of the κ-casein gene occurred at a higher frequency than allele B, in both Sahiwal and Tharparkar breeds. The genotypic frequencies of AA, AB, and BB in the Sahiwal and Tharparkar breeds were 0.758, 0.230 and 0.012, and 0.0.732, 0.250 and 0.018, respectively. The frequencies of alleles A and B in the Sahiwal and Tharparkar breeds were 0.873 and 0.127, and 0.857 and 0.143, respectively. Genotype BB of the kappa-casein gene had more influence on the monthly milk yield, 305-days milk yield, monthly solids-not-fat (SNF yield, and monthly protein yield, in the Sahiwal cattle.

  9. Global adaptive rank truncated product method for gene-set analysis in association studies.

    Science.gov (United States)

    Vilor-Tejedor, Natalia; Calle, M Luz

    2014-09-01

    Gene set analysis (GSA) aims to assess the overall association of a set of genetic variants with a phenotype and has the potential to detect subtle effects of variants in a gene or a pathway that might be missed when assessed individually. We present a new implementation of the Adaptive Rank Truncated Product method (ARTP) for analyzing the association of a set of Single Nucleotide Polymorphisms (SNPs) in a gene or pathway. The new implementation, referred to as globalARTP, improves the original one by allowing the different SNPs in the set to have different modes of inheritance. We perform a simulation study for exploring the power of the proposed methodology in a set of scenarios with different numbers of causal SNPs with different effect sizes. Moreover, we show the advantage of using the gene set approach in the context of an Alzheimer's disease case-control study where we explore the endocytosis pathway. The new method is implemented in the R function globalARTP of the globalGSA package available at http://cran.r-project.org. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Transcriptome and Gene Ontology (GO) Enrichment Analysis Reveals Genes Involved in Biotin Metabolism That Affect L-Lysine Production in Corynebacterium glutamicum.

    Science.gov (United States)

    Kim, Hong-Il; Kim, Jong-Hyeon; Park, Young-Jin

    2016-03-09

    Corynebacterium glutamicum is widely used for amino acid production. In the present study, 543 genes showed a significant change in their mRNA expression levels in L-lysine-producing C. glutamicum ATCC21300 than that in the wild-type C. glutamicum ATCC13032. Among these 543 differentially expressed genes (DEGs), 28 genes were up- or downregulated. In addition, 454 DEGs were functionally enriched and categorized based on BLAST sequence homologies and gene ontology (GO) annotations using the Blast2GO software. Interestingly, NCgl0071 (bioB, encoding biotin synthase) was expressed at levels ~20-fold higher in the L-lysine-producing ATCC21300 strain than that in the wild-type ATCC13032 strain. Five other genes involved in biotin metabolism or transport--NCgl2515 (bioA, encoding adenosylmethionine-8-amino-7-oxononanoate aminotransferase), NCgl2516 (bioD, encoding dithiobiotin synthetase), NCgl1883, NCgl1884, and NCgl1885--were also expressed at significantly higher levels in the L-lysine-producing ATCC21300 strain than that in the wild-type ATCC13032 strain, which we determined using both next-generation RNA sequencing and quantitative real-time PCR analysis. When we disrupted the bioB gene in C. glutamicum ATCC21300, L-lysine production decreased by approximately 76%, and the three genes involved in biotin transport (NCgl1883, NCgl1884, and NCgl1885) were significantly downregulated. These results will be helpful to improve our understanding of C. glutamicum for industrial amino acid production.

  11. Increased isobutanol production in Saccharomyces cerevisiae by overexpression of genes in valine metabolism

    DEFF Research Database (Denmark)

    Chen, Xiao; Nielsen, Kristian Fog; Borodina, Irina;

    2011-01-01

    of its relative tolerance to alcohols, robustness in industrial fermentations, and the possibility for future combination of isobutanol production with fermentation of lignocellulosic materials. RESULTS: The yield of isobutanol was improved from 0.16 to 0.97 mg per g glucose by simultaneous...... overexpression of biosynthetic genes ILV2, ILV3, and ILV5 in valine metabolism in anaerobic fermentation of glucose in mineral medium in S. cerevisiae. Isobutanol yield was further improved by twofold by the additional overexpression of BAT2, encoding the cytoplasmic branched-chain amino-acid aminotransferase...... were 3.86 and 0.28 mg per g glucose, respectively. They increased to 4.12 and 2.4 mg per g glucose in yeast extract/peptone/dextrose (YPD) complex medium under aerobic conditions, respectively. CONCLUSIONS: Overexpression of genes ILV2, ILV3, ILV5, and BAT2 in valine metabolism led to an increase...

  12. Deletion of pigR gene in Monascus ruber leads to loss of pigment production.

    Science.gov (United States)

    Xie, Nana; Liu, Qingpei; Chen, Fusheng

    2013-09-01

    Pigments produced by Monascus are traditional food colorants and are widely used as dietary supplements. Since genes involving in pigment biosynthesis have not been reported, we describe the identification of a putative pigment-regulatory gene (pigR) obtained by molecular analysis of an albino strain of Monascus ruber M7. In the pigR-deleted strain (ΔpigR), neither the pigments nor pigR expression were detected by HPLC or reverse-transcription PCR, respectively, whereas the introduction of the pigR, together with a constitutive trpC promoter into ΔpigR, caused it to produce 5.4 U of red pigments/g dry mycelia, about 12-fold higher than Monascus ruber M7 (0.46 U/g dry mycelia). Thus pigR up-regulates pigment production in Monascus ruber M7.

  13. Directed natural product biosynthesis gene cluster capture and expression in the model bacterium Bacillus subtilis

    Science.gov (United States)

    Li, Yongxin; Li, Zhongrui; Yamanaka, Kazuya; Xu, Ying; Zhang, Weipeng; Vlamakis, Hera; Kolter, Roberto; Moore, Bradley S.; Qian, Pei-Yuan

    2015-03-01

    Bacilli are ubiquitous low G+C environmental Gram-positive bacteria that produce a wide assortment of specialized small molecules. Although their natural product biosynthetic potential is high, robust molecular tools to support the heterologous expression of large biosynthetic gene clusters in Bacillus hosts are rare. Herein we adapt transformation-associated recombination (TAR) in yeast to design a single genomic capture and expression vector for antibiotic production in Bacillus subtilis. After validating this direct cloning ``plug-and-play'' approach with surfactin, we genetically interrogated amicoumacin biosynthetic gene cluster from the marine isolate Bacillus subtilis 1779. Its heterologous expression allowed us to explore an unusual maturation process involving the N-acyl-asparagine pro-drug intermediates preamicoumacins, which are hydrolyzed by the asparagine-specific peptidase into the active component amicoumacin A. This work represents the first direct cloning based heterologous expression of natural products in the model organism B. subtilis and paves the way to the development of future genome mining efforts in this genus.

  14. Directed natural product biosynthesis gene cluster capture and expression in the model bacterium Bacillus subtilis

    KAUST Repository

    Li, Yongxin

    2015-03-24

    Bacilli are ubiquitous low G+C environmental Gram-positive bacteria that produce a wide assortment of specialized small molecules. Although their natural product biosynthetic potential is high, robust molecular tools to support the heterologous expression of large biosynthetic gene clusters in Bacillus hosts are rare. Herein we adapt transformation-associated recombination (TAR) in yeast to design a single genomic capture and expression vector for antibiotic production in Bacillus subtilis. After validating this direct cloning plug-and-playa approach with surfactin, we genetically interrogated amicoumacin biosynthetic gene cluster from the marine isolate Bacillus subtilis 1779. Its heterologous expression allowed us to explore an unusual maturation process involving the N-acyl-asparagine pro-drug intermediates preamicoumacins, which are hydrolyzed by the asparagine-specific peptidase into the active component amicoumacin A. This work represents the first direct cloning based heterologous expression of natural products in the model organism B. subtilis and paves the way to the development of future genome mining efforts in this genus.

  15. Increased biomass production and glycogen accumulation in apcE gene deleted Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Joseph, Ancy; Aikawa, Shimpei; Sasaki, Kengo; Matsuda, Fumio; Hasunuma, Tomohisa; Kondo, Akihiko

    2014-01-01

    The effect of phycobilisome antenna-truncation in the cyanobacterium Synechocystis sp. PCC 6803 on biomass production and glycogen accumulation have not yet been fully clarified. To investigate these effects here, the apcE gene, which encodes the anchor protein linking the phycobilisome to the thylakoid membrane, was deleted in a glucose tolerant strain of Synechocystis sp. PCC 6803. Biomass production of the apcE-deleted strain under photoautotrophic and atmospheric air conditions was 1.6 times higher than that of strain PCC 6803 (1.32 ± 0.01 versus 0.84 ± 0.07 g cell-dry weight L(-1), respectively) after 15 days of cultivation. In addition, the glycogen content of the apcE-deleted strain (24.2 ± 0.7%) was also higher than that of strain PCC 6803 (11.1 ± 0.3%). Together, these results demonstrate that antenna truncation by deleting the apcE gene was effective for increasing biomass production and glycogen accumulation under photoautotrophic and atmospheric air conditions in Synechocystis sp. PCC 6803.

  16. DNA assembler: a synthetic biology tool for characterizing and engineering natural product gene clusters.

    Science.gov (United States)

    Shao, Zengyi; Zhao, Huimin

    2012-01-01

    The majority of existing antibacterial and anticancer drugs are natural products or their derivatives. However, the characterization and engineering of these compounds are often hampered by limited ability to manipulate the corresponding biosynthetic pathways. Recently, we developed a genomics-driven, synthetic biology-based method, DNA assembler, for discovery, characterization, and engineering of natural product biosynthetic pathways (Shao, Luo, & Zhao, 2011). By taking advantage of the highly efficient yeast in vivo homologous recombination mechanism, this method synthesizes the entire expression vector containing the target biosynthetic pathway and the genetic elements needed for DNA maintenance and replication in individual hosts in a single-step manner. In this chapter, we describe the general guidelines for construct design. By using two distinct biosynthetic pathways, we demonstrate that DNA assembler can perform multiple tasks, including heterologous expression, introduction of single or multiple point mutations, scar-less gene deletion, generation of product derivatives, and creation of artificial gene clusters. As such, this method offers unprecedented flexibility and versatility in pathway manipulations.

  17. Regulation of xanthine dehydrogensase gene expression and uric acid production in human airway epithelial cells.

    Science.gov (United States)

    Huff, Ryan D; Hsu, Alan C-Y; Nichol, Kristy S; Jones, Bernadette; Knight, Darryl A; Wark, Peter A B; Hansbro, Philip M; Hirota, Jeremy A

    2017-01-01

    The airway epithelium is a physical and immunological barrier that protects the pulmonary system from inhaled environmental insults. Uric acid has been detected in the respiratory tract and can function as an antioxidant or damage associated molecular pattern. We have demonstrated that human airway epithelial cells are a source of uric acid. Our hypothesis is that uric acid production by airway epithelial cells is induced by environmental stimuli associated with chronic respiratory diseases. We therefore examined how airway epithelial cells regulate uric acid production. Allergen and cigarette smoke mouse models were performed using house dust mite (HDM) and cigarette smoke exposure, respectively, with outcome measurements of lung uric acid levels. Primary human airway epithelial cells isolated from clinically diagnosed patients with asthma and chronic obstructive pulmonary disease (COPD) were grown in submerged cultures and compared to age-matched healthy controls for uric acid release. HBEC-6KT cells, a human airway epithelial cell line, were grown under submerged monolayer conditions for mechanistic and gene expression studies. HDM, but not cigarette smoke exposure, stimulated uric acid production in vivo and in vitro. Primary human airway epithelial cells from asthma, but not COPD patients, displayed elevated levels of extracellular uric acid in culture. In HBEC-6KT, production of uric acid was sensitive to the xanthine dehydrogenase (XDH) inhibitor, allopurinol, and the ATP Binding Cassette C4 (ABCC4) inhibitor, MK-571. Lastly, the pro-inflammatory cytokine combination of TNF-α and IFN-γ elevated extracellular uric acid levels and XDH gene expression in HBEC-6KT cells. Our results suggest that the active production of uric acid from human airway epithelial cells may be intrinsically altered in asthma and be further induced by pro-inflammatory cytokines.

  18. Suppression of Tla1 gene expression for improved solar conversion efficiency and photosynthetic productivity in plants and algae

    Science.gov (United States)

    Melis, Anastasios; Mitra, Mautusi

    2010-06-29

    The invention provides method and compositions to minimize the chlorophyll antenna size of photosynthesis by decreasing TLA1 gene expression, thereby improving solar conversion efficiencies and photosynthetic productivity in plants, e.g., green microalgae, under bright sunlight conditions.

  19. Characterization of foot-and-mouth disease virus gene products with antisera against bacterially synthesized fusion proteins

    Energy Technology Data Exchange (ETDEWEB)

    Strebel, K.; Beck, E.; Strohmaier, K.; Schaller, H.

    1986-03-01

    Defined segments of the cloned foot-and-mouth disease virus genome corresponding to all parts of the coding region were expressed in Escherichia coli as fusions to the N-terminal part of the MS2-polymerase gene under the control of the inducible lambdaPL promoter. All constructs yielded large amounts of proteins, which were purified and used to raise sequence-specific antisera in rabbits. These antisera were used to identify the corresponding viral gene products in /sup 35/S-labeled extracts from foot-and-mouth disease virus-infected BHK cells. This allowed us to locate unequivocally all mature foot-and-mouth disease virus gene products in the nucleotide sequence, to identify precursor-product relationships, and to detect several foot-and mouth disease virus gene products not previously identified in vivo or in vitro.

  20. Pseudomonas aeruginosa biofilms exposed to imipenem exhibit changes in global gene expression and beta-lactamase and alginate production

    DEFF Research Database (Denmark)

    Bagge, N.; Schuster, M.; Hentzer, Morten

    2004-01-01

    . As expected, the most strongly induced gene was ampC, which codes for chromosomal beta-lactamase. We also found that genes coding for alginate biosynthesis were induced by exposure to imipenem. Alginate production is correlated to the development of impaired lung function, and P. aeruginosa strains isolated...

  1. Functional analysis of the gene cluster involved in production of the bacteriocin circularin A by Clostridium beijerinckii ATCC 25752

    NARCIS (Netherlands)

    Kemperman, R; Jonker, M; Nauta, A; Kuipers, OP; Kok, J

    2003-01-01

    A region of 12 kb flanking the structural gene of the cyclic antibacterial peptide circularin A of Clostridium beijerinckii ATCC 25752 was sequenced, and the putative proteins involved in the production and secretion of circularin A were identified. The genes are tightly organized in overlapping ope

  2. Radiochemical identification of the kil gene product of bacteriophage lambda. [/sup 3/H, /sup 14/C, uv radiation, Esocherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Greer, H.; Ausubel, F.M.

    1979-06-01

    The coliphage lambda kil gene product has been identified using a differential labeling technique . The kil gene polypeptide has a molecular weight of about 16,000, as determined by sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Gel filtration of the kil protein indicates that it may exist as a tetramer in native form.

  3. Bayesian Computational Approaches for Gene Regulation Studies of Bioethanol and Biohydrogen Production. Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Newberg, Lee; McCue, Lee Anne; Van Roey, Patrick

    2014-04-17

    The project developed mathematical models and first-version software tools for the understanding of gene regulation across multiple related species. The project lays the foundation for understanding how certain alpha-proteobacterial species control their own genes for bioethanol and biohydrogen production, and sets the stage for exploiting bacteria for the production of fuels. Enabling such alternative sources of fuel is a high priority for the Department of Energy and the public.

  4. Natural and Engineered Hydroxyectoine Production Based on the Pseudomonas stutzeri ectABCD-ask Gene Cluster▿ †

    OpenAIRE

    Seip, Britta; Galinski, Erwin A.; Kurz, Matthias

    2010-01-01

    We report on the presence of a functional hydroxyectoine biosynthesis gene cluster, ectABCD-ask, in Pseudomonas stutzeri DSM5190T and evaluate the suitability of P. stutzeri DSM5190T for hydroxyectoine production. Furthermore, we present information on heterologous de novo production of the compatible solute hydroxyectoine in Escherichia coli. In this host, the P. stutzeri gene cluster remained under the control of its salt-induced native promoters. We also noted the absence of trehalose when...

  5. Expression of cell cycle-related gene products in different forms of primary versus recurrent PVNS.

    Science.gov (United States)

    Weckauf, Helgard; Helmchen, Birgit; Hinz, Ulf; Meyer-Scholten, Carola; Aulmann, Sebastian; Otto, Herwart F; Berger, Irina

    2004-07-08

    Expression patterns of cell cycle regulating gene products and Ki-67 in proliferating synovial cells of primary and recurrent pigmented villonodular synovitis (PVNS) in localized and diffuse lesions were examined by immunohistochemistry. Alterations of cell cycle-related proteins were seen in 98.7% of analyzed lesions. Both RB- and p53 pathways play a role in cell cycle dysregulation in PVNS. The RB pathway was more frequently altered in primary disease, while alterations of the p53 pathway seemed to be more important in recurrent lesions, regardless of the histomorphological type of disease. Ki-67 proliferation rate was elevated in recurrent tumors. Copyright 2004 Elsevier Ireland Ltd.

  6. Multiplexed, targeted gene editing in Nicotiana benthamiana for glyco-engineering and monoclonal antibody production.

    Science.gov (United States)

    Li, Jin; Stoddard, Thomas J; Demorest, Zachary L; Lavoie, Pierre-Olivier; Luo, Song; Clasen, Benjamin M; Cedrone, Frederic; Ray, Erin E; Coffman, Andrew P; Daulhac, Aurelie; Yabandith, Ann; Retterath, Adam J; Mathis, Luc; Voytas, Daniel F; D'Aoust, Marc-André; Zhang, Feng

    2016-02-01

    Biopharmaceutical glycoproteins produced in plants carry N-glycans with plant-specific residues core α(1,3)-fucose and β(1,2)-xylose, which can significantly impact the activity, stability and immunogenicity of biopharmaceuticals. In this study, we have employed sequence-specific transcription activator-like effector nucleases (TALENs) to knock out two α(1,3)-fucosyltransferase (FucT) and the two β(1,2)-xylosyltransferase (XylT) genes within Nicotiana benthamiana to generate plants with improved capacity to produce glycoproteins devoid of plant-specific residues. Among plants regenerated from N. benthamiana protoplasts transformed with TALENs targeting either the FucT or XylT genes, 50% (80 of 160) and 73% (94 of 129) had mutations in at least one FucT or XylT allele, respectively. Among plants regenerated from protoplasts transformed with both TALEN pairs, 17% (18 of 105) had mutations in all four gene targets, and 3% (3 of 105) plants had mutations in all eight alleles comprising both gene families; these mutations were transmitted to the next generation. Endogenous proteins expressed in the complete knockout line had N-glycans that lacked β(1,2)-xylose and had a significant reduction in core α(1,3)-fucose levels (40% of wild type). A similar phenotype was observed in the N-glycans of a recombinant rituximab antibody transiently expressed in the homozygous mutant plants. More importantly, the most desirable glycoform, one lacking both core α(1,3)-fucose and β(1,2)-xylose residues, increased in the antibody from 2% when produced in the wild-type line to 55% in the mutant line. These results demonstrate the power of TALENs for multiplexed gene editing. Furthermore, the mutant N. benthamiana lines provide a valuable platform for producing highly potent biopharmaceutical products.

  7. Self-association of the WT1 tumor suppressor gene product

    Energy Technology Data Exchange (ETDEWEB)

    Bruening, W.; Nakagama, H.: Bardessy, N. [McGill Univ., Montreal (Canada)] [and others

    1994-09-01

    Wilms` tumor (WT), an embryonal malignancy of the kidney, occurs most frequently in children under the age of 5 years, affecting {approximately}1 in 10,000 individuals. The WT1 tumor suppressor gene, residing at 11p13, is structurally altered in {approximately}10-15% of WT cases. Individuals with germline mutations within the WT1 gene suffer from predisposition to WT and developmental defects of the urogenital system. Patients with heterozygous deletions of the WT1 gene, or mutations predicted to cause inactivation of one WT1 allele, suffer relatively mild genital system defects (notably hypospadias and cryptorchidism in males) and a predisposition to WT. These results suggest that developing genital system development is sensitive to the absolute concentrations of the WT1 gene products. Patients with missense mutations within the WT1 gene, however, can suffer from a much more severe disorder known as Denys-Drash syndrome (DDS). This syndrome is characterized by intersex disorders, renal nephropathy, and a predisposition to WTs. The increased severity of the developmental defects associated with DDS, compared to those individuals with mild genital system anomalies and WTs, suggests that mutations defined in patients with DDS behave in a dominant-negative fashion. We have identified a novel WT1 mutation in a patient with DDS. This mutation, predicted to produce a truncated WT1 polypeptide encompassing exons 1, 2, and 3, defines a domain capable of behaving as an antimorph. We have also demonstrated that WT1 can self-associate in vivo using yeast two-hybrid systems. Deletion analysis have mapped the interacting domains to the amino terminus of the WT1 polypeptide, within exons 1 and 2. These results provide a molecular mechanism to explain how WT1 mutations can function in a dominant-negative fashion to eliminate wild-type WT1 activity, leading to DDS.

  8. Heterologous expression of the filarial nematode alt gene products reveals their potential to inhibit immune function

    Directory of Open Access Journals (Sweden)

    Aebischer Toni

    2005-03-01

    Full Text Available Abstract Background Parasites exploit sophisticated strategies to evade host immunity that require both adaptation of existing genes and evolution of new gene families. We have addressed this question by testing the immunological function of novel genes from helminth parasites, in which conventional transgenesis is not yet possible. We investigated two such novel genes from Brugia malayi termed abundant larval transcript (alt, expression of which reaches ~5% of total transcript at the time parasites enter the human host. Results To test the hypothesis that ALT proteins modulate host immunity, we adopted an alternative transfection strategy to express these products in the protozoan parasite Leishmania mexicana. We then followed the course of infection in vitro in macrophages and in vivo in mice. Expression of ALT proteins, but not a truncated mutant, conferred greater infectivity of macrophages in vitro, reaching 3-fold higher parasite densities. alt-transfected parasites also caused accelerated disease in vivo, and fewer mice were able to clear infection of organisms expressing ALT. alt-transfected parasites were more resistant to IFN-γ-induced killing by macrophages. Expression profiling of macrophages infected with transgenic L. mexicana revealed consistently higher levels of GATA-3 and SOCS-1 transcripts, both associated with the Th2-type response observed in in vivo filarial infection. Conclusion Leishmania transfection is a tractable and informative approach to determining immunological functions of single genes from heterologous organisms. In the case of the filarial ALT proteins, our data suggest that they may participate in the Th2 bias observed in the response to parasite infection by modulating cytokine-induced signalling within immune system cells.

  9. Phytoalexin detoxification genes and gene products: Implication for the evolution of host specific traits for pathogenicity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    VanEtten, H.

    1997-06-01

    The overall objectives of this research were to determine which differences among PDA genes were associated with different levels of virulence on pea and to clone and characterize a MAK gene. The authors also proposed to characterize the pisatin detoxifying system in pea pathogens in addition to N. haematococca to assess whether pathogens of a common host had evolved similar pathogenicity genes.

  10. Phytoalexin detoxification genes and gene products: Implication for the evolution of host specific traits for pathogenicity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    VanEtten, H.

    1997-06-01

    The overall objectives of this research were to determine which differences among PDA genes were associated with different levels of virulence on pea and to clone and characterize a MAK gene. The authors also proposed to characterize the pisatin detoxifying system in pea pathogens in addition to N. haematococca to assess whether pathogens of a common host had evolved similar pathogenicity genes.

  11. Effects of gene disruptions in the nisin gene cluster of Lactococcus lactis on nisin production and producer immunity

    NARCIS (Netherlands)

    Ra, Runar; Beerthuyzen, Marke M.; Vos, Willem M. de; Saris, Per E.J.; Kuipers, Oscar P.

    1999-01-01

    The lantibiotic nisin is produced by several strains of Lactococcus lactis subsp. lactis. The chromosomally located gene cluster nisABTCIPRKFEG is required for biosynthesis, development of immunity, and regulation of gene expression. In-frame deletions in the nisB and nisT genes, and disruption of

  12. Expression of herpes simplex virus. beta. and. gamma. genes integrated in mammalian cells and their induction by an. cap alpha. gene product

    Energy Technology Data Exchange (ETDEWEB)

    Sandri-Goldin, R.M.; Goldin, A.L.; Holland, L.E.

    1983-11-01

    The proteins of herpes simplex virus type 1 (HSV-1) form three kinetic groups termed ..cap alpha..,..beta..,and ..gamma.., whose synthesis is regulated in a cascade fashion, ..cap alpha.. products are synthesized first during infection, and they are required for synthesis of ..beta.. and ..gamma.. proteins. To examine the expression of several HSV-1 ..beta.. and ..gamma.. genes in the absence of ..cap alpha.. functions, we transferred into mammalian cells a plasmid containing a region of the HSV-1 genome that codes for only ..beta.. and ..gamma.. genes (0.315 to 0.421 map units). The authors found stable integration of at least one copy of the intact plasmid in each cell line. Four HSV-1 transcripts of the ..beta.. and ..gamma.. classes were transcribed constitutively in the cells, including the genes for glycoprotein B and DNA-binding protein. No constitutive synthesis of these two proteins could be demonstrated, however. The integrated HSV-1 genes responded to viral regulatory signals in that they could be induced by infection with HSV-1 mutants resulting in a high level of synthesis of both glycoprotein B and DNA-binding protein. The HSV-1 ..cap alpha.. gene product ICP4 was necessary for this induction, and it was found to be most efficient at a low multiplicity of infection. Functional expression of four genes was demonstrated in that the cell lines complemented infecting HSV-1 temperature-sensitive mutants. The same genes were not available for homologous recombination with infecting virus, however, since no recombinant wild-type virus could be detected. These data demonstrate that HSV-1 ..beta.. and ..gamma.. genes can be transcribed in the absence of ..cap alpha.. functions in mammalian cells, but that they still respond to HSV-1 regulatory signals such as the ..cap alpha.. gene product ICP4.

  13. Natural and Engineered Hydroxyectoine Production Based on the Pseudomonas stutzeri ectABCD-ask Gene Cluster▿ †

    Science.gov (United States)

    Seip, Britta; Galinski, Erwin A.; Kurz, Matthias

    2011-01-01

    We report on the presence of a functional hydroxyectoine biosynthesis gene cluster, ectABCD-ask, in Pseudomonas stutzeri DSM5190T and evaluate the suitability of P. stutzeri DSM5190T for hydroxyectoine production. Furthermore, we present information on heterologous de novo production of the compatible solute hydroxyectoine in Escherichia coli. In this host, the P. stutzeri gene cluster remained under the control of its salt-induced native promoters. We also noted the absence of trehalose when hydroxyectoine genes were expressed, as well as a remarkable inhibitory effect of externally applied betaine on hydroxyectoine synthesis. The specific heterologous production rate in E. coli under the conditions employed exceeded that of the natural producer Pseudomonas stutzeri and, for the first time, enabled effective hydroxyectoine production at low salinity (2%), with the added advantage of simple product processing due to the absence of other cosolutes. PMID:21169432

  14. 5-Aminolevulinate production by Escherichia coli containing the Rhodobacter sphaeroides hemA gene

    Energy Technology Data Exchange (ETDEWEB)

    Van Der Werf, M.J. [Michigan State Univ., East Lansing, MI (United States); Zeikus, J.G. [Michigan State Univ., East Lansing, MI (United States)]|[MBI International, Lansing, MI (United States)

    1996-10-01

    The Rhodobacter sphaeroides hemA gene codes for 5-aminolevulinate (ALA) synthase. This enzyme catalyzes the pyridoxal phosphate-dependent condensation of succinyl coenzyme A and glycine-forming ALA. The R. sphaeroides hemA gene in the pUC18/19 vector system was transformed into Escherichia coli. The effects of both genetic and physiological factors on the expression of ALA synthase and the production of ALA were studied. ALA synthase activity levels were maximal when hemA had the same transcription direction as the lac promoter. The distance between the lac promoter and hemA affected the expression of ALA synthase on different growth substrates. The E. coli host strain used had an enormous effect on the ALA synthase activity level and on the production of ALA, with E. coli DH1 being best suited. The ALA synthase activity level was also dependent on the carbon source. Succinate, L-malate, fumarate, and L-aspartate gave the highest levels of ALA synthase activity, while the use of lactose as a carbon source resulted in a repression of ALA synthase. After growth on succinate, ALA synthase represented {approx}5% of total cellular protein. The ALA synthase activity level was also dependent on the pH of the medium, with maximal activity occurring at pH 6.5. ALA production by whole cells was limited by the availability of glycine, and the addition of 2 g of glycine per liter to the growth medium increased the production of ALA fivefold, to 2.25 mM. In recombinant E. coli extracts, up to 22 mM ALA was produced from succinate, glycine, and ATP. 58 refs., 4 figs., 7 tabs.

  15. Increased isobutanol production in Saccharomyces cerevisiae by overexpression of genes in valine metabolism

    Directory of Open Access Journals (Sweden)

    Karhumaa Kaisa

    2011-07-01

    Full Text Available Abstract Background Isobutanol can be a better biofuel than ethanol due to its higher energy density and lower hygroscopicity. Furthermore, the branched-chain structure of isobutanol gives a higher octane number than the isomeric n-butanol. Saccharomyces cerevisiae was chosen as the production host because of its relative tolerance to alcohols, robustness in industrial fermentations, and the possibility for future combination of isobutanol production with fermentation of lignocellulosic materials. Results The yield of isobutanol was improved from 0.16 to 0.97 mg per g glucose by simultaneous overexpression of biosynthetic genes ILV2, ILV3, and ILV5 in valine metabolism in anaerobic fermentation of glucose in mineral medium in S. cerevisiae. Isobutanol yield was further improved by twofold by the additional overexpression of BAT2, encoding the cytoplasmic branched-chain amino-acid aminotransferase. Overexpression of ILV6, encoding the regulatory subunit of Ilv2, in the ILV2 ILV3 ILV5 overexpression strain decreased isobutanol production yield by threefold. In aerobic cultivations in shake flasks in mineral medium, the isobutanol yield of the ILV2 ILV3 ILV5 overexpression strain and the reference strain were 3.86 and 0.28 mg per g glucose, respectively. They increased to 4.12 and 2.4 mg per g glucose in yeast extract/peptone/dextrose (YPD complex medium under aerobic conditions, respectively. Conclusions Overexpression of genes ILV2, ILV3, ILV5, and BAT2 in valine metabolism led to an increase in isobutanol production in S. cerevisiae. Additional overexpression of ILV6 in the ILV2 ILV3 ILV5 overexpression strain had a negative effect, presumably by increasing the sensitivity of Ilv2 to valine inhibition, thus weakening the positive impact of overexpression of ILV2, ILV3, and ILV5 on isobutanol production. Aerobic cultivations of the ILV2 ILV3 ILV5 overexpression strain and the reference strain showed that supplying amino acids in cultivation media

  16. Re-examination of regulatory opinions in Europe: possible contribution for the approval of the first gene therapy product Glybera

    Science.gov (United States)

    Watanabe, Natsumi; Yano, Kazuo; Tsuyuki, Kenichiro; Okano, Teruo; Yamato, Masayuki

    2015-01-01

    The first commercially approved human gene therapy in the Western world is Glybera (alipogene tiparvovec), which is an adenoassociated viral vector encoding the lipoprotein lipase gene. Glybera was recommended for marketing authorization by the European Medicines Agency in 2012. The European Medicines Agency had only ever reviewed three marketing authorization applications for gene therapy medicinal products. Unlike in the case of Glybera, the applications of the first two products, Cerepro and Contusugene Ladenovec Gendux/Advexin, both of which were for cancer diseases, were withdrawn. In this report, we studied the European public assessment reports of the three gene therapy products. During the assessment process, Glybera was re-examined and reviewed for a fourth time. We therefore researched the re-examination procedure of the European Union regulatory process. Approximately 25% of the new medicinal products initially given negative opinions from the Committee for Medicinal Products for Human Use were ultimately approved after re-examination from 2009 to 2013. The indications of most medicines were changed during the re-examination procedure, and the products were later approved with a mode of approval. These results suggested that the re-examination system in the European Union contributed to the approval of both several new drugs and the first gene therapy product. PMID:26052534

  17. Induction of hematopoietic microchimerism by gene-modified BMT elicits antigen-specific B and T cell unresponsiveness toward gene therapy products

    Directory of Open Access Journals (Sweden)

    Jérémie Martinet

    2016-09-01

    Full Text Available Background: Gene therapy is a promising treatment option for hemophilia and other protein deficiencies. However, immune responses against the transgene product represent an obstacle to safe and effective gene therapy, urging for the implementation of tolerization strategies. Induction of a hematopoietic chimerism via bone marrow transplantation (BMT is a potent means for inducing immunological tolerance in solid organ transplantation. Objectives: We reasoned here that the same viral vector could be used firstly to transduce BM cells for inducing chimerism-associated transgene-specific immune tolerance and, secondly, for correcting protein deficiencies by vector-mediated systemic production of the deficient coagulation factor.Methods: Evaluation of strategies to induce B and T cell tolerance was performed using ex vivo gene transfer with lentiviral vectors encoding coagulation factor IX (FIX or the SIINFEKL epitope of ovalbumin. Following induction of microchimerism via BMT, animals were challenged with in vivo gene transfer with lentiviral vectors.Results: The experimental approach prevented humoral immune response against FIX, resulting in persistence of therapeutic levels of circulating FIX after lentiviral-mediated gene transfer in vivo. In an ovalbumin model, we also demonstrated that this approach effectively tolerized the CD8+ T cell compartment in an antigen-specific manner.Conclusions: These results provide the proof-of-concept that inducing a microchimerism by gene-modified BMT is a powerful tool to provide transgene-specific B and T cell tolerance in a gene therapy setting.

  18. c-Myb influences HIV type 1 gene expression and virus production.

    Science.gov (United States)

    Churchill, M J; Ramsay, R G; Rhodes, D I; Deacon, N J

    2001-11-01

    c-Myb is expressed in proliferating T cells. Fifteen c-Myb-binding sites can be identified in the HIV-1 long terminal repeat (LTR), suggesting that c-Myb may regulate HIV-1 gene expression and virus replication. Increasing the cellular levels of c-Myb by transient transfection of CEM cells resulted in a 10- to 20-fold activation of HIV-1 LTR-driven gene expression and mutation of one high-affinity Myb-binding site within the LTR reduced this activation by 60 to 70%. Conversely, inhibition of c-Myb expression in MT-2 cells by treatment with c-myb antisense oligonucleotides decreased HIV-1 replication by 85%, as measured by reverse transcriptase activity and cytopathic effects. The effect of c-myb antisense oligonucleotides on HIV-1 gene expression and virus particle production appeared to be independent of cell proliferation, but dependent on the presence of c-Myb activity mediated through the HIV-1 LTR. These data show that c-myb expression affects HIV-1 replication in CD4(+) T cells.

  19. A genetic strategy to measure circulating Drosophila insulin reveals genes regulating insulin production and secretion.

    Science.gov (United States)

    Park, Sangbin; Alfa, Ronald W; Topper, Sydni M; Kim, Grace E S; Kockel, Lutz; Kim, Seung K

    2014-08-01

    Insulin is a major regulator of metabolism in metazoans, including the fruit fly Drosophila melanogaster. Genome-wide association studies (GWAS) suggest a genetic basis for reductions of both insulin sensitivity and insulin secretion, phenotypes commonly observed in humans with type 2 diabetes mellitus (T2DM). To identify molecular functions of genes linked to T2DM risk, we developed a genetic tool to measure insulin-like peptide 2 (Ilp2) levels in Drosophila, a model organism with superb experimental genetics. Our system permitted sensitive quantification of circulating Ilp2, including measures of Ilp2 dynamics during fasting and re-feeding, and demonstration of adaptive Ilp2 secretion in response to insulin receptor haploinsufficiency. Tissue specific dissection of this reduced insulin signaling phenotype revealed a critical role for insulin signaling in specific peripheral tissues. Knockdown of the Drosophila orthologues of human T2DM risk genes, including GLIS3 and BCL11A, revealed roles of these Drosophila genes in Ilp2 production or secretion. Discovery of Drosophila mechanisms and regulators controlling in vivo insulin dynamics should accelerate functional dissection of diabetes genetics.

  20. Disruption of the acetate kinase (ack) gene of Clostridium acetobutylicum results in delayed acetate production.

    Science.gov (United States)

    Kuit, Wouter; Minton, Nigel P; López-Contreras, Ana M; Eggink, Gerrit

    2012-05-01

    In microorganisms, the enzyme acetate kinase (AK) catalyses the formation of ATP from ADP by de-phosphorylation of acetyl phosphate into acetic acid. A mutant strain of Clostridium acetobutylicum lacking acetate kinase activity is expected to have reduced acetate and acetone production compared to the wild type. In this work, a C. acetobutylicum mutant strain with a selectively disrupted ack gene, encoding AK, was constructed and genetically and physiologically characterized. The ack (-) strain showed a reduction in acetate kinase activity of more than 97% compared to the wild type. The fermentation profiles of the ack (-) and wild-type strain were compared using two different fermentation media, CGM and CM1. The latter contains acetate and has a higher iron and magnesium content than CGM. In general, fermentations by the mutant strain showed a clear shift in the timing of peak acetate production relative to butyrate and had increased acid uptake after the onset of solvent formation. Specifically, in acetate containing CM1 medium, acetate production was reduced by more than 80% compared to the wild type under the same conditions, but both strains produced similar final amounts of solvents. Fermentations in CGM showed similar peak acetate and butyrate levels, but increased acetoin (60%), ethanol (63%) and butanol (16%) production and reduced lactate (-50%) formation by the mutant compared to the wild type. These findings are in agreement with the proposed regulatory function of butyryl phosphate as opposed to acetyl phosphate in the metabolic switch of solventogenic clostridia.

  1. Fermentative hydrogen production from Jerusalem artichoke by Clostridium tyrobutyricum expressing exo-inulinase gene.

    Science.gov (United States)

    Jiang, Ling; Wu, Qian; Xu, Qing; Zhu, Liying; Huang, He

    2017-08-11

    Clostridium tyrobutyricum ATCC25755 has been reported as being able to produce significant quantities of hydrogen. In this study, the exo-inulinase encoding gene cloned from Paenibacillus polymyxa SC-2 was into the expression plasmid pSY6 and expressed in the cells of C. tyrobutyricum. The engineered C. tyrobutyricum strain efficiently fermented the inulin-type carbohydrates from Jerusalem artichoke, without any pretreatment being necessary for the production of hydrogen. A comparatively high hydrogen yield (3.7 mol/mol inulin-type sugar) was achieved after 96 h in a batch process with simultaneous saccharification and fermentation (SSF), with an overall volumetric productivity rate of 620 ± 60 mL/h/L when the initial total sugar concentration of the inulin extract was increased to 100 g/L. Synthesis of inulinase in the batch SSF culture was closely associated with strain growth until the end of the exponential phase, reaching a maximum activity of 28.4 ± 0.26 U/mL. The overall results show that the highly productive and abundant biomass crop Jerusalem artichoke can be a good substrate for hydrogen production, and that the application of batch SSF for its conversion has the potential to become a cost-effective process in the near future.

  2. EFFECT OF KANGLEMYCIN C ON LYMPHOKIN A PRODUCTION AND GENE EXPRESSION OF MOUSE SPLENOCYTE AND MACROPHAGE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Ain. To study the effect of kanglemycin C (KC) on production and gene transcription of lymphokins. Methods. Cell proliferation and lymphokin activities were quantified with MTT colorimetry and ELISA, and genetranscripdons of lymphokins semi-quantified with RT-PCR. Restlts. Suppression of KC on proliferation of enriched T-and B-cell respectively mediated by Con A and LPS was declined by addition of exogenous IL-1, IL-2, and IL-6. KC 80 nmol/L markedly inhibited IL-2 and IL-6 pro-duction and mRNA transcription of incubated mouse splenocytes induced by Con A. Additionally, KC had some sup-pression on IL-1β and IL-6 productions of peritoneal macrophage stimulated by LPS (5 μg/mL), whereas cyclosporine(CS) had not. Condusion. Immunosuppression of KC came true partially through the decrease of IL-1β, -2 and -6 productions,especially of IL-2. However, CS's immunosuppression was mainly through the decrease of IL-2 procduction.

  3. Essential Oils Modulate Gene Expression and Ochratoxin A Production in Aspergillus carbonarius.

    Science.gov (United States)

    El Khoury, Rachelle; Atoui, Ali; Verheecke, Carol; Maroun, Richard; El Khoury, Andre; Mathieu, Florence

    2016-08-19

    Ochratoxin A (OTA) is a mycotoxin, mainly produced on grapes by Aspergillus carbonarius, that causes massive health problems for humans. This study aims to reduce the occurrence of OTA by using the ten following essential oils (E.Os): fennel, cardamom, anise, chamomile, celery, cinnamon, thyme, taramira, oregano and rosemary at 1 µL/mL and 5 µL/mL for each E.O.As a matter of fact, their effects on the OTA production and the growth of A. carbonarius S402 cultures were evaluated, after four days at 28 °C on a Synthetic Grape Medium (SGM). Results showed that A. carbonarius growth was reduced up to 100%, when cultured with the E.Os of cinnamon, taramira, and oregano at both concentrations and the thyme at 5 µL/mL. As for the other six E.Os, their effect on A. carbonarius growth was insignificant, but highly important on the OTA production. Interestingly, the fennel E.O at 5 µL/mL reduced the OTA production up to 88.9% compared to the control, with only 13.8% of fungal growth reduction. We further investigated the effect of these E.Os on the expression levels of the genes responsible for the OTA biosynthesis (acOTApks and acOTAnrps along with the acpks gene) as well as the two regulatory genes laeA and vea, using the quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) method. The results revealed that these six E.Os reduced the expression of the five studied genes, where the ackps was downregulated by 99.2% (the highest downregulation in this study) with 5 µL/mL of fennel E.O.As for the acOTApks, acOTAnrps, veA and laeA, their reduction levels ranged between 10% and 96% depending on the nature of the E.O and its concentration in the medium.

  4. Essential Oils Modulate Gene Expression and Ochratoxin A Production in Aspergillus carbonarius

    Science.gov (United States)

    El Khoury, Rachelle; Atoui, Ali; Verheecke, Carol; Maroun, Richard; El Khoury, Andre; Mathieu, Florence

    2016-01-01

    Ochratoxin A (OTA) is a mycotoxin, mainly produced on grapes by Aspergillus carbonarius, that causes massive health problems for humans. This study aims to reduce the occurrence of OTA by using the ten following essential oils (E.Os): fennel, cardamom, anise, chamomile, celery, cinnamon, thyme, taramira, oregano and rosemary at 1 µL/mL and 5 µL/mL for each E.O.As a matter of fact, their effects on the OTA production and the growth of A. carbonarius S402 cultures were evaluated, after four days at 28 °C on a Synthetic Grape Medium (SGM). Results showed that A. carbonarius growth was reduced up to 100%, when cultured with the E.Os of cinnamon, taramira, and oregano at both concentrations and the thyme at 5 µL/mL. As for the other six E.Os, their effect on A. carbonarius growth was insignificant, but highly important on the OTA production. Interestingly, the fennel E.O at 5 µL/mL reduced the OTA production up to 88.9% compared to the control, with only 13.8% of fungal growth reduction. We further investigated the effect of these E.Os on the expression levels of the genes responsible for the OTA biosynthesis (acOTApks and acOTAnrps along with the acpks gene) as well as the two regulatory genes laeA and vea, using the quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) method. The results revealed that these six E.Os reduced the expression of the five studied genes, where the ackps was downregulated by 99.2% (the highest downregulation in this study) with 5 µL/mL of fennel E.O.As for the acOTApks, acOTAnrps, veA and laeA, their reduction levels ranged between 10% and 96% depending on the nature of the E.O and its concentration in the medium. PMID:27548221

  5. Nucleotide and protein sequences for dog masticatory tropomyosin identify a novel Tpm4 gene product.

    Science.gov (United States)

    Brundage, Elizabeth A; Biesiadecki, Brandon J; Reiser, Peter J

    2015-10-01

    Jaw-closing muscles of several vertebrate species, including members of Carnivora, express a unique, "masticatory", isoform of myosin heavy chain, along with isoforms of other myofibrillar proteins that are not expressed in most other muscles. It is generally believed that the complement of myofibrillar isoforms in these muscles serves high force generation for capturing live prey, breaking down tough plant material and defensive biting. A unique isoform of tropomyosin (Tpm) was reported to be expressed in cat jaw-closing muscle, based upon two-dimensional gel mobility, peptide mapping, and immunohistochemistry. The objective of this study was to obtain protein and gene sequence information for this unique Tpm isoform. Samples of masseter (a jaw-closing muscle), tibialis (predominantly fast-twitch fibers), and the deep lateral gastrocnemius (predominantly slow-twitch fibers) were obtained from adult dogs. Expressed Tpm isoforms were cloned and sequencing yielded cDNAs that were identical to genomic predicted striated muscle Tpm1.1St(a,b,b,a) (historically referred to as αTpm), Tpm2.2St(a,b,b,a) (βTpm) and Tpm3.12St(a,b,b,a) (γTpm) isoforms (nomenclature reflects predominant tissue expression ("St"-striated muscle) and exon splicing pattern), as well as a novel 284 amino acid isoform observed in jaw-closing muscle that is identical to a genomic predicted product of the Tpm4 gene (δTpm) family. The novel isoform is designated as Tpm4.3St(a,b,b,a). The myofibrillar Tpm isoform expressed in dog masseter exhibits a unique electrophoretic mobility on gels containing 6 M urea, compared to other skeletal Tpm isoforms. To validate that the cloned Tpm4.3 isoform is the Tpm expressed in dog masseter, E. coli-expressed Tpm4.3 was electrophoresed in the presence of urea. Results demonstrate that Tpm4.3 has identical electrophoretic mobility to the unique dog masseter Tpm isoform and is of different mobility from that of muscle Tpm1.1, Tpm2.2 and Tpm3.12 isoforms. We

  6. Effect of retS gene on antibiotics production in Pseudomonas fluorescens FD6.

    Science.gov (United States)

    Zhang, Qingxia; Xiao, Qi; Xu, Jingyou; Tong, Yunhui; Wen, Jia; Chen, Xijun; Wei, Lihui

    2015-11-01

    A hybrid sensor kinase termed RetS (regulator of exopolysaccharide and Type III secretion) controls expression of numerous genes in Pseudomonas aeruginosa. To investigate the function of RetS in P. fluorescens FD6, the retS gene was disrupted. Genetic inactivation of retS resulted in enhanced production of 2, 4-diacetylphloroglucinol, pyrrolnitrin, and pyoluteorin. The retS mutant also exhibited significant increase in phlA-lacZ, prnA-lacZ, and pltA-lacZ transcription levels, influencing expression levels of the small regulatory RNAs RsmX and RsmZ. In the gacSretS double mutant, all the phenotypic changes caused by the retS deletion were reversed to the level of gacS single mutant. Furthermore, the retS mutation drastically elevated biofilm formation and improved the colonization ability of strain FD6 on wheat rhizospheres. Based on these results, we proposed that RetS negatively controlled the production of antibiotics through the Gac/Rsm pathway in P. fluorescens FD6.

  7. Quantitative trait loci linked to PRNP gene controlling health and production traits in INRA 401 sheep

    Directory of Open Access Journals (Sweden)

    Brunel Jean-Claude

    2007-07-01

    Full Text Available Abstract In this study, the potential association of PrP genotypes with health and productive traits was investigated. Data were recorded on animals of the INRA 401 breed from the Bourges-La Sapinière INRA experimental farm. The population consisted of 30 rams and 852 ewes, which produced 1310 lambs. The animals were categorized into three PrP genotype classes: ARR homozygous, ARR heterozygous, and animals without any ARR allele. Two analyses differing in the approach considered were carried out. Firstly, the potential association of the PrP genotype with disease (Salmonella resistance and production (wool and carcass traits was studied. The data used included 1042, 1043 and 1013 genotyped animals for the Salmonella resistance, wool and carcass traits, respectively. The different traits were analyzed using an animal model, where the PrP genotype effect was included as a fixed effect. Association analyses do not indicate any evidence of an effect of PrP genotypes on traits studied in this breed. Secondly, a quantitative trait loci (QTL detection approach using the PRNP gene as a marker was applied on ovine chromosome 13. Interval mapping was used. Evidence for one QTL affecting mean fiber diameter was found at 25 cM from the PRNP gene. However, a linkage between PRNP and this QTL does not imply unfavorable linkage disequilibrium for PRNP selection purposes.

  8. Use of Heme Compounds as Iron Sources by Pathogenic Neisseriae Requires the Product of the hemO Gene

    OpenAIRE

    2000-01-01

    Heme compounds are an important source of iron for neisseriae. We have identified a neisserial gene, hemO, that is essential for heme, hemoglobin (Hb), and haptoglobin-Hb utilization. The hemO gene is located 178 bp upstream of the hmbR Hb receptor gene in Neisseria meningitidis isolates. The product of the hemO gene is homologous to enzymes that degrade heme; 21% of its amino acid residues are identical, and 44% are similar, to those of the human heme oxygenase-1. DNA sequences homologous to...

  9. A mutation in the aroE gene affects pigment production, virulence, and chemotaxis in Xanthomonas oryzae pv. oryzae.

    Science.gov (United States)

    Kim, Hong-Il; Noh, Tae-Hwan; Lee, Chang-Soo; Park, Young-Jin

    2015-01-01

    Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB) in rice. To study its function, a random insertion mutation library of Xoo was constructed using the Tn5 transposon. A mutant strain with decreased virulence against the susceptible rice cultivar IR24 was isolated from the library (aroE mutant), which also had extremely low pigment production. Thermal asymmetric interlaced-polymerase chain reaction (TAIL-PCR) and sequence analysis of the mutant revealed that the transposon was inserted into the aroE gene (encoding shikimate dehydrogenase). To investigate gene expression changes in the pigment- and virulence-deficient mutant, DNA microarray analysis was performed, which showed downregulation of 20 genes involved in the chemotaxis of Xoo. Our findings reveal that mutation of the aroE gene affects virulence and pigment production, as well as expression of genes involved in Xoo chemotaxis.

  10. [Improvement of natamycin production in an industrial strain by heterologous expression of the afsRS(cla) global regulatory genes].

    Science.gov (United States)

    Tao, Zhengsheng; Wang, Yemin; Zheng, Hualiang; Tao, Meifeng

    2015-05-01

    The afsRS(cla) global regulatory genes from Streptomyces clavuligerus activate the production of two antibiotics in Streptomyces lividans. In this study, we gained an increase of 38% in the production of natamycin (3.56 g/L) in an industrial strain Streptomyces gilvosporeus TZ1401 through the integration of pHL851 that bears the afsRS(cla) global regulatory genes into its genome. We discovered by quantitive real-time reverse transcription PCR (qRT-PCR) that the expression of 6 genes of the natamycin biosynthetic gene cluster were improved from 1.9 to 2.7 times. This suggests that afsRS(cla) improve the production of natamycin through increased transcription. This study provides a good example for applying afsRS(cla) in high yield breeding of industrial antibiotic producers.

  11. Diversity, distribution and quantification of antibiotic resistance genes in goat and lamb slaughterhouse surfaces and meat products.

    Directory of Open Access Journals (Sweden)

    Leyre Lavilla Lerma

    Full Text Available The distribution and quantification of tetracycline, sulfonamide and beta-lactam resistance genes were assessed in slaughterhouse zones throughout meat chain production and the meat products; this study represents the first to report quantitatively monitor antibiotic resistance genes (ARG in goat and lamb slaughterhouse using a culture independent approach, since most studies focused on individual bacterial species and their specific resistance types. Quantitative PCR (qPCR revealed a high prevalence of tetracycline resistance genes tetA and tetB in almost all slaughterhouse zones. Sulfonamide resistance genes were largely distributed, while beta-lactam resistance genes were less predominant. Statistical analysis revealed that resistant bacteria, in most cases, were spread by the same route in almost all slaughterhouse zones, except for tetB, blaCTX and blaTEM genes, which occurred in few zones as isolated 'hot spots.' The sum of all analyzed ARG indicated that slaughterhouse surfaces and end products act as reservoirs of ARG, mainly tet genes, which were more prevalent in slaughtering room (SR, cutting room (CR and commercial meat products (MP. Resistance gene patterns suggest they were disseminated throughout slaughterhouse zones being also detected in commercial meat products, with significant correlations between different sampling zones/end products and total resistance in SR, CR and white room (WR zones, and also refrigerator 4 (F4 and MP were observed. Strategically controlling key zones in slaughterhouse (SR, CR and WR by adequate disinfection methods could strategically reduce the risks of ARG transmission and minimize the issues of food safety and environment contamination.

  12. Diversity, Distribution and Quantification of Antibiotic Resistance Genes in Goat and Lamb Slaughterhouse Surfaces and Meat Products

    Science.gov (United States)

    Lavilla Lerma, Leyre; Benomar, Nabil; Knapp, Charles W.; Correa Galeote, David; Gálvez, Antonio; Abriouel, Hikmate

    2014-01-01

    The distribution and quantification of tetracycline, sulfonamide and beta-lactam resistance genes were assessed in slaughterhouse zones throughout meat chain production and the meat products; this study represents the first to report quantitatively monitor antibiotic resistance genes (ARG) in goat and lamb slaughterhouse using a culture independent approach, since most studies focused on individual bacterial species and their specific resistance types. Quantitative PCR (qPCR) revealed a high prevalence of tetracycline resistance genes tetA and tetB in almost all slaughterhouse zones. Sulfonamide resistance genes were largely distributed, while beta-lactam resistance genes were less predominant. Statistical analysis revealed that resistant bacteria, in most cases, were spread by the same route in almost all slaughterhouse zones, except for tetB, blaCTX and blaTEM genes, which occurred in few zones as isolated ‘hot spots.’ The sum of all analyzed ARG indicated that slaughterhouse surfaces and end products act as reservoirs of ARG, mainly tet genes, which were more prevalent in slaughtering room (SR), cutting room (CR) and commercial meat products (MP). Resistance gene patterns suggest they were disseminated throughout slaughterhouse zones being also detected in commercial meat products, with significant correlations between different sampling zones/end products and total resistance in SR, CR and white room (WR) zones, and also refrigerator 4 (F4) and MP were observed. Strategically controlling key zones in slaughterhouse (SR, CR and WR) by adequate disinfection methods could strategically reduce the risks of ARG transmission and minimize the issues of food safety and environment contamination. PMID:25479100

  13. A gene optimization strategy that enhances production of fully functional P-glycoprotein in Pichia pastoris.

    Directory of Open Access Journals (Sweden)

    Jiangping Bai

    Full Text Available BACKGROUND: Structural and biochemical studies of mammalian membrane proteins remain hampered by inefficient production of pure protein. We explored codon optimization based on highly expressed Pichia pastoris genes to enhance co-translational folding and production of P-glycoprotein (Pgp, an ATP-dependent drug efflux pump involved in multidrug resistance of cancers. METHODOLOGY/PRINCIPAL FINDINGS: Codon-optimized "Opti-Pgp" and wild-type Pgp, identical in primary protein sequence, were rigorously analyzed for differences in function or solution structure. Yeast expression levels and yield of purified protein from P. pastoris (∼130 mg per kg cells were about three-fold higher for Opti-Pgp than for wild-type protein. Opti-Pgp conveyed full in vivo drug resistance against multiple anticancer and fungicidal drugs. ATP hydrolysis by purified Opti-Pgp was strongly stimulated ∼15-fold by verapamil and inhibited by cyclosporine A with binding constants of 4.2±2.2 µM and 1.1±0.26 µM, indistinguishable from wild-type Pgp. Maximum turnover number was 2.1±0.28 µmol/min/mg and was enhanced by 1.2-fold over wild-type Pgp, likely due to higher purity of Opti-Pgp preparations. Analysis of purified wild-type and Opti-Pgp by CD, DSC and limited proteolysis suggested similar secondary and ternary structure. Addition of lipid increased the thermal stability from T(m ∼40 °C to 49 °C, and the total unfolding enthalpy. The increase in folded state may account for the increase in drug-stimulated ATPase activity seen in presence of lipids. CONCLUSION: The significantly higher yields of protein in the native folded state, higher purity and improved function establish the value of our gene optimization approach, and provide a basis to improve production of other membrane proteins.

  14. ASSOCIATIONS BETWEEN SNPs IN BOVINE ESTROGEN RECEPTOR GENE AND PRODUCTION TRAITS IN HOLSTEIN CATTLE

    Directory of Open Access Journals (Sweden)

    Nina Moravčíková

    2015-02-01

    Full Text Available aim of this study was to determine allelic and genotypic frequency of two SNPs in ERα gene and evaluate the associations between ERα genetic variants and milk production traits in Holstein cattle. Analysis of the molecular mechanisms involved in the regulation of reproduction in connection with milk production and followed genotyping of the individuals with optimal genetic potential may facilitate the animal selection in dairy cattle farms. Genomic DNA was obtained in total from 150 hair root samples of Holstein cows. Two polymorphic sites in 5´region on ERα gene (BTA6 were analysed. Genotyping of animals was carried out by PCR-RFLP method using SnaBI and BglI restriction endonucleases. After restriction analyses was detected in population the presence of two ERα/SnaBI (GG, AG, and three ERα/BglI genotypes (GG, AG, AA. The highest proportion was found for individuals with ERα/SnaBI GG (85% and ERα/BglI AA (83% genotypes. The missing of ERα/SnaBI AA genotype was reflected to the higher distribution of G allele (0.92± 0.02. For the ERα/BglI polymorphism was observed the higher frequency of A allele (0.91±0.02. The differences between observed and expected genotype frequencies caused the deviations from HWE in locus ERα/SnaBI. The statistical analyses of ERα genotypes effect on milk production traits was performed with linear models (GLM procedure. Based on the selected effect we were able to estimate the variability of analyzed traits on 80%. The ERα/SnaBI and ERα/BglI genotypes affected the variability of milk, protein and fat yield only non-significant (P > 0.05.

  15. Enhanced biosurfactant production through cloning of three genes and role of esterase in biosurfactant release

    Directory of Open Access Journals (Sweden)

    Khanna Sunil

    2011-06-01

    Full Text Available Abstract Background Biosurfactants have been reported to utilize a number of immiscible substrates and thereby facilitate the biodegradation of panoply of polyaromatic hydrocarbons. Olive oil is one such carbon source which has been explored by many researchers. However, studying the concomitant production of biosurfactant and esterase enzyme in the presence of olive oil in the Bacillus species and its recombinants is a relatively novel approach. Results Bacillus species isolated from endosulfan sprayed cashew plantation soil was cultivated on a number of hydrophobic substrates. Olive oil was found to be the best inducer of biosurfactant activity. The protein associated with the release of the biosurfactant was found to be an esterase. There was a twofold increase in the biosurfactant and esterase activities after the successful cloning of the biosurfactant genes from Bacillus subtilis SK320 into E.coli. Multiple sequence alignment showed regions of similarity and conserved sequences between biosurfactant and esterase genes, further confirming the symbiotic correlation between the two. Biosurfactants produced by Bacillus subtilis SK320 and recombinant strains BioS a, BioS b, BioS c were found to be effective emulsifiers, reducing the surface tension of water from 72 dynes/cm to as low as 30.7 dynes/cm. Conclusion The attributes of enhanced biosurfactant and esterase production by hyper-producing recombinant strains have many utilities from industrial viewpoint. This study for the first time has shown a possible association between biosurfactant production and esterase activity in any Bacillus species. Biosurfactant-esterase complex has been found to have powerful emulsification properties, which shows promising bioremediation, hydrocarbon biodegradation and pharmaceutical applications.

  16. Microarray-based gene expression analysis as a process characterization tool to establish comparability of complex biological products: scale-up of a whole-cell immunotherapy product.

    Science.gov (United States)

    Wang, Min; Senger, Ryan S; Paredes, Carlos; Banik, Gautam G; Lin, Andy; Papoutsakis, Eleftherios T

    2009-11-01

    Whole-cell immunotherapies and other cellular therapies have shown promising results in clinical trials. Due to the complex nature of the whole cell product and of the sometimes limited correlation of clinical potency with the proposed mechanism of action, these cellular immunotherapy products are generally not considered well characterized. Therefore, one major challenge in the product development of whole cell therapies is the ability to demonstrate comparability of product after changes in the manufacturing process. Such changes are nearly inevitable with increase in manufacturing experience leading to improved and robust processes that may have higher commercial feasibility. In order to comprehensively assess the impact of the process changes on the final product, and thus establish comparability, a matrix of characterization assays (in addition to lot release assays) assessing the various aspects of the cellular product are required. In this study, we assessed the capability of DNA-microarray-based, gene-expression analysis as a characterization tool using GVAX cancer immunotherapy cells manufactured by Cell Genesys, Inc. The GVAX immunotherapy product consists two prostate cancer cell lines (CG1940 and CG8711) engineered to secrete human GM-CSF. To demonstrate the capability of the assay, we assessed the transcriptional changes in the product when produced in the presence or absence of fetal bovine serum, and under normal and hypoxic conditions, both changes intended to stress the cell lines. We then assessed the impact of an approximately 10-fold process scale-up on the final product at the transcriptional level. These data were used to develop comparisons and statistical analyses suitable for characterizing culture reproducibility and cellular product similarity. Use of gene-expression data for process characterization proved to be a reproducible and sensitive method for detecting differences due to small or large changes in culture conditions as might be

  17. Production of staphylococcal enterotoxins in microbial broth and milk by Staphylococcus aureus strains harboring seh gene.

    Science.gov (United States)

    Schubert, Justyna; Podkowik, Magdalena; Bystroń, Jarosław; Bania, Jacek

    2016-10-17

    Twenty Staphylococcus aureus strains harboring seh gene, including one carrying also sec gene and 11 sea gene, were grown in BHI+YE broth and milk and were tested for SEA, SEC and SEH production. All strains decreased pH of BHI+YE broth at 24h and increased them at 48h. Seventeen S. aureus strains grown in milk changed pH for no >0.3 unit until 48h. Three other S. aureus strains significantly decreased pH during growth in milk. All S. aureus produced SEH in BHI+YE broth in amounts ranging from 95 to 1292ng/ml, and from 170 to 4158ng/ml at 24 and 48h, respectively. SEH production in milk by 17 strains did not exceed 23ng/ml at 24h and 36ng/ml at 48h. Three S. aureus strains able to decrease milk pH produced 107-3029ng/ml and 320-4246ng/ml of SEH in milk at 24 and 48h, respectively. These strains were grown in milk and BHI+YE broth with pH stabilized at values near neutral leading to a significant decrease of SEH production. Representative weak SEH producers were grown in milk at reduced pH resulting in moderate increase in SEH production. SEA was produced in milk by 10S. aureus strains at 24-151ng/ml at 24h, and 31-303ng/ml at 48h. SEA production in milk was higher or comparable as in BHI+YE broth in 3 strains and lower for remaining strains. Production of SEC by sec-positive S. aureus strains was lower in milk than in BHI+YE broth, ranging from 131 to 2319ng/ml at 24 and 48h in milk and 296-30,087ng/ml in BHI+YE at 24 and 48h. Both lacE and lacG transcripts involved in lactose metabolism were significantly up-regulated in milk in strong SEH producers. In these strains hld, rot and sarA transcripts were up-regulated in milk as compared to weak SEH producers. Stabilization of milk pH at a value of raw milk significantly down-regulated hld, rot and sarA RNA in strong SEH producers. Milk was generally found unfavorable for enterotoxin production. However, certain S. aureus strains were not restricted in SEH and SEA expression in milk, unlike SEC which remained down

  18. Increasing Avermectin Production in Streptomyces avermitilis by Manipulating the Expression of a Novel TetR-Family Regulator and Its Target Gene Product.

    Science.gov (United States)

    Liu, Wenshuai; Zhang, Qinling; Guo, Jia; Chen, Zhi; Li, Jilun; Wen, Ying

    2015-08-01

    Avermectins produced by Streptomyces avermitilis are commercially important anthelmintic agents. The detailed regulatory mechanisms of avermectin biosynthesis remain unclear. Here, we identified SAV3619, a TetR-family transcriptional regulator designated AveT, to be an activator for both avermectin production and morphological differentiation in S. avermitilis. AveT was shown to indirectly stimulate avermectin production by affecting transcription of the cluster-situated activator gene aveR. AveT directly repressed transcription of its own gene (aveT), adjacent gene pepD2 (sav_3620), sav_7490 (designated aveM), and sav_7491 by binding to an 18-bp perfect palindromic sequence (CGAAACGKTKYCGTTTCG, where K is T or G and Y is T or C and where the underlining indicates inverted repeats) within their promoter regions. aveM (which encodes a putative transmembrane efflux protein belonging to the major facilitator superfamily [MFS]), the important target gene of AveT, had a striking negative effect on avermectin production and morphological differentiation. Overexpression of aveT and deletion of aveM in wild-type and industrial strains of S. avermitilis led to clear increases in the levels of avermectin production. In vitro gel-shift assays suggested that C-5-O-B1, the late pathway precursor of avermectin B1, acts as an AveT ligand. Taken together, our findings indicate positive-feedback regulation of aveT expression and avermectin production by a late pathway intermediate and provide the basis for an efficient strategy to increase avermectin production in S. avermitilis by manipulation of AveT and its target gene product, AveM.

  19. MitoRes: a resource of nuclear-encoded mitochondrial genes and their products in Metazoa

    Directory of Open Access Journals (Sweden)

    Grillo Giorgio

    2006-01-01

    Full Text Available Abstract Background Mitochondria are sub-cellular organelles that have a central role in energy production and in other metabolic pathways of all eukaryotic respiring cells. In the last few years, with more and more genomes being sequenced, a huge amount of data has been generated providing an unprecedented opportunity to use the comparative analysis approach in studies of evolution and functional genomics with the aim of shedding light on molecular mechanisms regulating mitochondrial biogenesis and metabolism. In this context, the problem of the optimal extraction of representative datasets of genomic and proteomic data assumes a crucial importance. Specialised resources for nuclear-encoded mitochondria-related proteins already exist; however, no mitochondrial database is currently available with the same features of MitoRes, which is an update of the MitoNuc database extensively modified in its structure, data sources and graphical interface. It contains data on nuclear-encoded mitochondria-related products for any metazoan species for which this type of data is available and also provides comprehensive sequence datasets (gene, transcript and protein as well as useful tools for their extraction and export. Description MitoRes http://www2.ba.itb.cnr.it/MitoRes/ consolidates information from publicly external sources and automatically annotates them into a relational database. Additionally, it also clusters proteins on the basis of their sequence similarity and interconnects them with genomic data. The search engine and sequence management tools allow the query/retrieval of the database content and the extraction and export of sequences (gene, transcript, protein and related sub-sequences (intron, exon, UTR, CDS, signal peptide and gene flanking regions ready to be used for in silico analysis. Conclusion The tool we describe here has been developed to support lab scientists and bioinformaticians alike in the characterization of molecular

  20. Deletion of cagA gene of Helicobacter pylori by PCR products

    Institute of Scientific and Technical Information of China (English)

    Xun Zeng; Li-Hua He; Yan Yin; Mao-Jun Zhang; Jian-Zhong Zhang

    2005-01-01

    AIM: Cytotoxin-associated protein (antigen) A (CagA)plays an important role in Helicobacter pylori(H pylori)pathogenesis. Our aim was to obtain cagA mutant strains by a new mutation method so as to better understand the mechanism of CagA in epithelial cells. METHODS: In contrast with the traditional method using suicide plasmid, we constructed cagA- mutant strains directly with PCR products. The constructed mutant clones grew on selective media and allelic exchange was confirmed by Southern blot. Furthermore, two different transformation methods, electroporation, and natural transformation, were compared with regard to the efficiency of recombination.RESULTS: The mutation by PCR products could be completed within 3-5 d, and the recombination rate by electroporation and natural transformation was 4.02×10-8 and 1.03x 10-9 respectively. Mutation rate by electroporation (4.02× 10-8) was far higher than by natural transformation (1.03× 10-9) (P = 0.000<0.005).CONCLUSION: cagA- mutant strains have been constructed,which is important for further study on the function of CagA in epithelial cells. A mutation method by directly using PCR products has been proved successful with a much higher mutation rate, and is easier, especially when in combination with electroporation. This method could be widely used in gene deletion of H pylori.

  1. Molecular detection of adulteration in chicken products based on mitochondrial 12S rRNA gene.

    Science.gov (United States)

    Abuzinadah, Osama H A; Yacoub, Haitham Ahmed; El Ashmaoui, Hassan M; Ramadan, Hassan A I

    2015-06-01

    The aim of this study is to detect the fraudulent in chicken products constitutes in order to protect consumers in Saudi Arabia from illegal substitutions. Two different approaches were used in this study, direct sequencing of specific fragments of amplified mitochondrial 12S rRNA gene in addition to species-specific PCR primers for confirmation of the obtained Blast search results. The results showed that all processed chicken products were identified as chicken (Gallus gallus) by 90-98% homology depending on obtained sequence quality. Samples labeled with chicken luncheon (samples tested in this study) were identified as turkey meat (Meleagris gallopavo) by 98% homology, suggesting adulteration with inedible parts of turkey in chicken luncheon ingredients. The results showed also that not only chicken luncheon was mixed with inedible parts of turkey but also all chicken products tested in this study (chicken balls, chicken burger, chicken sausage and chicken mined meat) contained this turkey meat. Applying methods used in this study could be useful for accurate and rapid identification of commercial processed meat.

  2. Cellulosic Ethanol Production by Recombinant Cellulolytic Bacteria Harbouring pdc and adh II Genes of Zymomonas mobilis.

    Science.gov (United States)

    Piriya, P Sobana; Vasan, P Thirumalai; Padma, V S; Vidhyadevi, U; Archana, K; Vennison, S John

    2012-01-01

    The ethanol fermenting genes such as pyruvate decarboxylase (pdc) and alcohol dehydrogenase II (adh II) were cloned from Zymomonas mobilis and transformed into three different cellulolytic bacteria, namely Enterobacter cloacae JV, Proteus mirabilis JV and Erwinia chrysanthemi and their cellulosic ethanol production capability was studied. Recombinant E. cloacae JV was found to produce 4.5% and 3.5% (v/v) ethanol, respectively, when CMC and 4% NaOH pretreated bagasse were used as substrates, whereas recombinant P. mirabilis and E. chrysanthemi with the same substrates could only produce 4%, 3.5%, 1%, and 1.5 % of ethanol, respectively. The recombinant E. cloacae strain produced twofold higher percentage of ethanol than the wild type. The recombinant E. cloacae strain could be improved further by increasing its ethanol tolerance capability through media optimization and also by combining multigene cellulase expression for enhancing ethanol production from various types of lignocellulosic biomass so that it can be used for industrial level ethanol production.

  3. Genes Linked to Production of Secondary Metabolites in Talaromyces atroroseus Revealed Using CRISPR-Cas9

    Science.gov (United States)

    Nielsen, Maria Lund; Isbrandt, Thomas; Rasmussen, Kasper Bøwig; Thrane, Ulf; Hoof, Jakob Blæsbjerg; Larsen, Thomas Ostenfeld; Mortensen, Uffe Hasbro

    2017-01-01

    The full potential of fungal secondary metabolism has until recently been impeded by the lack of universal genetic tools for most species. However, the emergence of several CRISPR-Cas9-based genome editing systems adapted for several genera of filamentous fungi have now opened the doors for future efforts in discovery of novel natural products and elucidation and engineering of their biosynthetic pathways in fungi where no genetic tools are in place. So far, most studies have focused on demonstrating the performance of CRISPR-Cas9 in various fungal model species, and recently we presented a versatile CRISPR-Cas9 system that can be successfully applied in several diverse Aspergillus species. Here we take it one step further and show that our system can be used also in a phylogenetically distinct and largely unexplored species from the genus of Talaromyces. Specifically, we exploit CRISPR-Cas9-based genome editing to identify a new gene in T. atroroseus responsible for production of polyketide-nonribosomal peptide hybrid products, hence, linking fungal secondary metabolites to their genetic origin in a species where no genetic engineering has previously been performed. PMID:28056079

  4. Improvement of clavulanic acid production in Streptomyces clavuligerus by genetic manipulation of structural biosynthesis genes.

    Science.gov (United States)

    Jnawali, Hum Nath; Yoo, Jin Cheol; Sohng, Jae Kyung

    2011-06-01

    To enhance clavulanic acid production, four structural clavulanic acid biosynthesis genes, carboxyethylarginine synthase (ceas2), β-lactam synthetase (bls2), clavaminate synthase (cas2) and proclavaminate amidinohydrolase (pah2), were amplified from Streptomyces clavuligerus genomic DNA. They were cloned in the pSET152 integration and pIBR25 expression vectors containing the strong ermE* promoter to generate pHN18 and pHN19, respectively, and both plasmids were introduced into S. clavuligerus by protoplast transformation. Clavulanic acid production was increased by 8.7-fold (to ~310 mg/l) in integrative pHN18 transformants and by 5.1-fold in pHN19 transformants compared to controls. Transcriptional analyses showed that the expression levels of ceas2, bls2, cas2 and pah2 were markedly increased in both transformants as compared with wild-type. The elevation of the ceas2, bls2, cas2 and pah2 transcripts was consistent with the enhanced production of clavulanic acid.

  5. Cellulosic Ethanol Production by Recombinant Cellulolytic Bacteria Harbouring pdc and adh II Genes of Zymomonas mobilis

    Directory of Open Access Journals (Sweden)

    P. Sobana Piriya

    2012-01-01

    Full Text Available The ethanol fermenting genes such as pyruvate decarboxylase (pdc and alcohol dehydrogenase II (adh II were cloned from Zymomonas mobilis and transformed into three different cellulolytic bacteria, namely Enterobacter cloacae JV, Proteus mirabilis JV and Erwinia chrysanthemi and their cellulosic ethanol production capability was studied. Recombinant E. cloacae JV was found to produce 4.5% and 3.5% (v/v ethanol, respectively, when CMC and 4% NaOH pretreated bagasse were used as substrates, whereas recombinant P. mirabilis and E. chrysanthemi with the same substrates could only produce 4%, 3.5%, 1%, and 1.5 % of ethanol, respectively. The recombinant E. cloacae strain produced twofold higher percentage of ethanol than the wild type. The recombinant E. cloacae strain could be improved further by increasing its ethanol tolerance capability through media optimization and also by combining multigene cellulase expression for enhancing ethanol production from various types of lignocellulosic biomass so that it can be used for industrial level ethanol production.

  6. Overexpression of polyphosphate kinase gene (ppk) increases bioinsecticide production by Bacillus thuringiensis.

    Science.gov (United States)

    Doruk, Tugrul; Avican, Ummehan; Camci, Irem Yalim; Gedik, Sedef Tunca

    2013-05-06

    Polyphosphate (polyP), synthesized by polyP kinase (PPK) using the terminal phosphate of ATP as substrate, performs important functions in every living cell. The present work reports on the relationship between polyP metabolism and bioinsecticide production in Bacillus thuringiensis subsp. israelensis (Bti). The ppk gene of Bti was cloned into vector pHT315 and the effect of its overexpression on endotoxin production was determined. Endotoxin production by the recombinant strain was found to be consistently higher than that by the wild type strain and the strain that carried the empty plasmid. The toxicity of the recombinant mutant strain (LC50 5.8±0.6ngml(-1)) against late 2nd instar Culex quinquefasciatus was about 7.7 times higher than that of Bti (LC50 44.9±7ngml(-1)). To our knowledge this is the first reported study which relates polyP metabolism with bioinsecticide biosynthesis. Copyright © 2012 Elsevier GmbH. All rights reserved.

  7. Genes Linked to Production of Secondary Metabolites in Talaromyces atroroseus Revealed Using CRISPR-Cas9.

    Science.gov (United States)

    Nielsen, Maria Lund; Isbrandt, Thomas; Rasmussen, Kasper Bøwig; Thrane, Ulf; Hoof, Jakob Blæsbjerg; Larsen, Thomas Ostenfeld; Mortensen, Uffe Hasbro

    2017-01-01

    The full potential of fungal secondary metabolism has until recently been impeded by the lack of universal genetic tools for most species. However, the emergence of several CRISPR-Cas9-based genome editing systems adapted for several genera of filamentous fungi have now opened the doors for future efforts in discovery of novel natural products and elucidation and engineering of their biosynthetic pathways in fungi where no genetic tools are in place. So far, most studies have focused on demonstrating the performance of CRISPR-Cas9 in various fungal model species, and recently we presented a versatile CRISPR-Cas9 system that can be successfully applied in several diverse Aspergillus species. Here we take it one step further and show that our system can be used also in a phylogenetically distinct and largely unexplored species from the genus of Talaromyces. Specifically, we exploit CRISPR-Cas9-based genome editing to identify a new gene in T. atroroseus responsible for production of polyketide-nonribosomal peptide hybrid products, hence, linking fungal secondary metabolites to their genetic origin in a species where no genetic engineering has previously been performed.

  8. L-lactic acid production from D-xylose with Candida sonorensis expressing a heterologous lactate dehydrogenase encoding gene.

    Science.gov (United States)

    Koivuranta, Kari T; Ilmén, Marja; Wiebe, Marilyn G; Ruohonen, Laura; Suominen, Pirkko; Penttilä, Merja

    2014-08-08

    Bioplastics, like polylactic acid (PLA), are renewable alternatives for petroleum-based plastics. Lactic acid, the monomer of PLA, has traditionally been produced biotechnologically with bacteria. With genetic engineering, yeast have the potential to replace bacteria in biotechnological lactic acid production, with the benefits of being acid tolerant and having simple nutritional requirements. Lactate dehydrogenase genes have been introduced to various yeast to demonstrate this potential. Importantly, an industrial lactic acid producing process utilising yeast has already been implemented. Utilisation of D-xylose in addition to D-glucose in production of biochemicals such as lactic acid by microbial fermentation would be beneficial, as it would allow lignocellulosic raw materials to be utilised in the production processes. The yeast Candida sonorensis, which naturally metabolises D-xylose, was genetically modified to produce L-lactic acid from D-xylose by integrating the gene encoding L-lactic acid dehydrogenase (ldhL) from Lactobacillus helveticus into its genome. In microaerobic, CaCO3-buffered conditions a C. sonorensis ldhL transformant having two copies of the ldhL gene produced 31 g l-1 lactic acid from 50 g l-1 D-xylose free of ethanol.Anaerobic production of lactic acid from D-xylose was assessed after introducing an alternative pathway of D-xylose metabolism, i.e. by adding a xylose isomerase encoded by XYLA from Piromyces sp. alone or together with the xylulokinase encoding gene XKS1 from Saccharomyces cerevisiae. Strains were further modified by deletion of the endogenous xylose reductase encoding gene, alone or together with the xylitol dehydrogenase encoding gene. Strains of C. sonorensis expressing xylose isomerase produced L-lactic acid from D-xylose in anaerobic conditions. The highest anaerobic L-lactic acid production (8.5 g l-1) was observed in strains in which both the xylose reductase and xylitol dehydrogenase encoding genes had been

  9. Production of host shutoff-defective mutants of herpes simplex virus type 1 by inactivation of the UL13 gene.

    Science.gov (United States)

    Overton, H; McMillan, D; Hope, L; Wong-Kai-In, P

    1994-07-01

    Two mutants of HSV-1(SC16) carrying disrupted UL13 genes have been generated independently by recombination of wild-type genomic DNA with a plasmid-cloned copy of the UL13 gene containing multiple stop codons. The two mutants were shown to be deficient in UL13 gene expression by Western blotting of infected cells. A revertant virus, in which UL13 expression was restored to a near-normal level, was generated by recombination of one of the UL13-negative mutants with a plasmid carrying the wild-type UL13 gene. The replication of the two UL13-negative viruses in cell culture was somewhat reduced compared to their wild-type parent, and the viruses were unable to produce shutoff of host protein synthesis. The replication of the revertant virus was intermediate between that of the UL13-negative and wild-type viruses, as was its ability to produce host shutoff. Cells infected with the UL13-negative mutants were shown to contain much lower levels than normal of the UL41 gene product, which is known to be required for virion host shutoff. However, there was no significant difference between levels of the UL41 gene product in wild-type and mutant virions. The UL13-negative viruses exhibited different patterns of protein phosphorylation from wild-type virus when infected cells were metabolically labeled with [32P]-orthophosphate and when lysates of infected cells and of virions were subjected to in vitro phosphorylation. However, the UL41 gene product could still be phosphorylated in lysates of UL13-negative virions. We conclude that the UL13 gene is necessary to produce the virion host shutoff effect, but it seems unlikely that the role of UL13 is simply to activate the UL41 gene product by phosphorylation.

  10. SYBR® Green qPCR Screening Methods for Detection of Anti-herbicide Genes in Genetically Modiifed Processed Products

    Institute of Scientific and Technical Information of China (English)

    Zhen Zhen; Lv Wei; Tang Zhi-fen; Liu Ying; Ao Jin-xia; Yuan Xiao-han; Zhang Ming-hui; Qiu You-wen; Gao Xue-jun

    2016-01-01

    The use of genetically modified organisms (GMOs) as food products becomes more and more widespread. The European Union has implemented a set of very strict procedures for the approval to grow, import and/or utilize GMOs as food or food ingredients. Thus, analytical methods for detection of GMOs are necessary in order to verify compliance with labelling requirements. There are few effective screening methods for processed GM (genetically modified) products. Three anti-herbicide genes (CP4-EPSPS,BAR andPAT) are common exogenous genes used in commercialized transgenic soybean, maize and rice. In the present study, a new SYBR® Green qPCR screening method was developed to simultaneously detect the three exogenous anti-herbicide genes and one endogenous gene in a run. We tested seven samples of representative processed products (soya lecithin, soya protein powder, chocolate beverage, infant rice cereal, maize protein powder, maize starch, and maize jam) using the developed method, and amplicons of endogenous gene and transgenic fragments were obtained from all the processed products, and the sensitivity was 0.1%. These results indicated that SYBR® Green qPCR screening method was appropriate for qualitative detection of transgenic soybean, maize and rice in processed products.

  11. Analysis of β-galactosidase production and their genes of two strains of Lactobacillus bulgaricus.

    Science.gov (United States)

    Zhang, Wen; Wang, Chuan; Huang, Cheng-Yu; Yu, Qian; Liu, Heng-Chuan; Zhang, Chao-Wu; Pei, Xiao-Fang; Xu, Xin; Wang, Guo-Qing

    2012-06-01

    A bacterial β-galactosidase delivery system is a potential therapy for lactose intolerance. Currently, two Lactobacillus bulgaricus strains with different biological characteristics are under consideration as potential sources. However, differences in these β-galactosidase genes and their resulting production levels are poorly characterized. The β-galactosidase ORF of L. bulgaricus yogurt isolate had high variability and was terminated at site 1924 due to a stop codon. However, the full 114 kDa β-galactosidase band was still resolved by SDS-PAGE, which may indicate that the interrupted ORF was translated into more than one peptide, and they together were folded into the complete enzyme protein that showed much higher β-galactosidase activity (6.2 U/mg protein) than the enzyme generated from L. bulgaricus reference strain (2.5 U/mg protein).

  12. Properties of the Macrophomina phaseolina endoglucanase (EGL 1) gene product in bacterial and yeast expression systems.

    Science.gov (United States)

    Wang, H; Jones, R W

    1999-09-01

    Functional expression of a beta-D-1,4 glucanase-encoding gene (egl1) from a filamentous fungus was achieved in both Escherichia coli and Saccharomyces cerevisiae using a modified version of pRS413. Optimal activity of the E. coli-expressed enzyme was found at incubation temperatures of 60 degrees C, whereas the enzyme activity was optimal at 40 degrees C when expressed by S. cerevisiae. Enzyme activity at different pH levels was similar for both bacteria and yeast, being highest at 5.0. Yeast expression resulted in a highly glycosylated protein of approx 60 kDa, compared to bacterial expression, which resulted in a protein of 30 kDa. The hyperglycosylated protein had reduced enzyme activity, indicating that E. coli is a preferred vehicle for production scale-up.

  13. Deletion of degQ gene enhances outer membrane vesicle production of Shewanella oneidensis cells.

    Science.gov (United States)

    Ojima, Yoshihiro; Mohanadas, Thivagaran; Kitamura, Kosei; Nunogami, Shota; Yajima, Reiki; Taya, Masahito

    2017-04-01

    Shewanella oneidensis is a Gram-negative facultative anaerobe that can use a wide variety of terminal electron acceptors for anaerobic respiration. In this study, S. oneidensis degQ gene, encoding a putative periplasmic serine protease, was cloned and expressed. The activity of purified DegQ was inhibited by diisopropyl fluorophosphate, a typical serine protease-specific inhibitor, indicating that DegQ is a serine protease. In-frame deletion and subsequent complementation of the degQ were carried out to examine the effect of envelope stress on the production of outer membrane vesicles (OMVs). Analysis of periplasmic proteins from the resulting S. oneidensis strain showed that deletion of degQ induced protein accumulation and resulted in a significant decrease in protease activity within the periplasmic space. OMVs from the wild-type and mutant strains were purified and observed by transmission electron microscopy. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the OMVs showed a prominent band at ~37 kDa. Nanoliquid chromatography-tandem mass spectrometry analysis identified three outer membrane porins (SO3896, SO1821, and SO3545) as dominant components of the band, suggesting that these proteins could be used as indices for comparing OMV production by S. oneidensis strains. Quantitative evaluation showed that degQ-deficient cells had a fivefold increase in OMV production compared with wild-type cells. Thus, the increased OMV production following the deletion of DegQ in S. oneidensis may be responsible for the increase in envelope stress.

  14. Non-ribosomal peptide synthetases: Identifying the cryptic gene clusters and decoding the natural product

    Indian Academy of Sciences (India)

    MANGAL SINGH; SANDEEP CHAUDHARY; DIPTI SAREEN

    2017-03-01

    Non-ribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs) present in bacteria and fungi are themajor multi-modular enzyme complexes which synthesize secondary metabolites like the pharmacologically importantantibiotics and siderophores. Each of the multiple modules of an NRPS activates a different amino or aryl acid,followed by their condensation to synthesize a linear or cyclic natural product. The studies on NRPS domains, theknowledge of their gene cluster architecture and tailoring enzymes have helped in the in silico genetic screening of theever-expanding sequenced microbial genomic data for the identification of novel NRPS/PKS clusters and thusdeciphering novel non-ribosomal peptides (NRPs). Adenylation domain is an integral part of the NRPSs and is thesubstrate selecting unit for the final assembled NRP. In some cases, it also requires a small protein, the MbtHhomolog, for its optimum activity. The presence of putative adenylation domain and MbtH homologs in a sequencedgenome can help identify the novel secondary metabolite producers. The role of the adenylation domain in the NRPSgene clusters and its characterization as a tool for the discovery of novel cryptic NRPS gene clusters are discussed.

  15. IL-8 and MCP Gene Expression and Production by LPS-Stimulated Human Corneal Stromal Cells

    Directory of Open Access Journals (Sweden)

    Roni M. Shtein

    2012-01-01

    Full Text Available Purpose. To determine time course of effect of lipopolysaccharide (LPS on production of interleukin-8 (IL-8 and monocyte chemotactic protein (MCP by cultured human corneal stromal cells. Methods. Human corneal stromal cells were harvested from donor corneal specimens, and fourth to sixth passaged cells were used. Cell cultures were stimulated with LPS for 2, 4, 8, and 24 hours. Northern blot analysis of IL-8 and MCP gene expression and ELISA for IL-8 and MCP secretion were performed. ELISA results were analyzed for statistical significance using two-tailed Student's t-test. Results. Northern blot analysis demonstrated significantly increased IL-8 and MCP gene expression after 4 and 8 hours of exposure to LPS. ELISA for secreted IL-8 and MCP demonstrated statistically significant increases (P<0.05 after corneal stromal cell stimulation with LPS. Conclusions. This paper suggests that human corneal stromal cells may participate in corneal inflammation by secreting potent leukocyte chemotactic and activating proteins in a time-dependent manner when exposed to LPS.

  16. Structural and mechanistic studies of the orf12 gene product from the clavulanic acid biosynthesis pathway.

    Science.gov (United States)

    Valegård, Karin; Iqbal, Aman; Kershaw, Nadia J; Ivison, David; Généreux, Catherine; Dubus, Alain; Blikstad, Cecilia; Demetriades, Marina; Hopkinson, Richard J; Lloyd, Adrian J; Roper, David I; Schofield, Christopher J; Andersson, Inger; McDonough, Michael A

    2013-08-01

    Structural and biochemical studies of the orf12 gene product (ORF12) from the clavulanic acid (CA) biosynthesis gene cluster are described. Sequence and crystallographic analyses reveal two domains: a C-terminal penicillin-binding protein (PBP)/β-lactamase-type fold with highest structural similarity to the class A β-lactamases fused to an N-terminal domain with a fold similar to steroid isomerases and polyketide cyclases. The C-terminal domain of ORF12 did not show β-lactamase or PBP activity for the substrates tested, but did show low-level esterase activity towards 3'-O-acetyl cephalosporins and a thioester substrate. Mutagenesis studies imply that Ser173, which is present in a conserved SXXK motif, acts as a nucleophile in catalysis, consistent with studies of related esterases, β-lactamases and D-Ala carboxypeptidases. Structures of wild-type ORF12 and of catalytic residue variants were obtained in complex with and in the absence of clavulanic acid. The role of ORF12 in clavulanic acid biosynthesis is unknown, but it may be involved in the epimerization of (3S,5S)-clavaminic acid to (3R,5R)-clavulanic acid.

  17. Prokaryotic Expression of Rice Ospgip1 Gene and Bioinformatic Analysis of Encoded Product

    Institute of Scientific and Technical Information of China (English)

    CHEN Xi-jun; LIU Xiao-wei; Zuo Si-min; MA Yu-yin; TONG Yun-hui; PAN Xue-biao; XU Jing-you

    2011-01-01

    Using the reference sequences of pgip genes in GenBank,a fragment of 930 bp covering the open reading frame (ORF) of rice Ospgip1 (Oryza sativa polygalacturonase-inhibiting protein 1) was amplified.The prokaryotic expression product of the gene inhibited the growth of Rhizoctonia solani,the causal agent of rice sheath blight,and reduced its polygalacturonase activity.Bioinformatic analysis showed that OsPGIP1 is a hydrophobic protein with a molecular weight of 32.8 kDa and an isoelectric point (pl) of 7.26.The protein is mainly located in the cell wall of rice,and its signal peptide cleavage site is located between the 17th and 18th amino acids.There are four cysteines in both the N-and C-termini of the deduced protein,which can form three disulfide bonds (between the 56th and 63rd,the 278th and 298th,and the 300th and308th amino acids).The protein has a typical leucine-rich repeat (LRR) domain,and its secondary structure comprises α-helices,β-sheets and irregular coils.Compared with polygalacturonase-inhibiting proteins (PGIPs) from other plants,the 7th LRR is absent in OsPGIP1.The nine LRRs could form a cleft that might associate with proteins from pathogenic fungi,such as polygalacturonase.

  18. Relationship between gene polymorphism and milk production traits in Teleorman Black Head sheep breed

    Directory of Open Access Journals (Sweden)

    Gras MA

    2015-12-01

    Full Text Available Objective. This study is a preliminary step of a larger national program aimed to develop a strategy for “in situ” preservation of Teleorman Black Head sheep population. In this paper we estimated the effect of β-lactoglobulin, casein and prolactin on some quantitative and qualitative milk traits in this local sheep population. Material and methods. Genotyping methodology included PCR for CSN3 (A and B alleles and PCR-RFLP for LGB (A and B alleles and PRL (T and C alleles, respectively. Repeated milking and milk composition analysis were used for the polymorphism effect estimation. Results. No association between CSN3 polymorphism and milk traits was found. Effect of LGB on production traits was quite constant. Genotype AA performed better than BB. PRL marker effect showed small differences than LGB. Concerning milk, fat and protein yield, AA genotype for PRL had a smaller positive impact than AA genotype for LGB. Regarding fat and protein content, PRL showed a negative effect for AA and positive for BB genotype, respectively. Conclusions. Positive association between LGB and milk yield and composition recommend this candidate gene like marker for a future MAS program. Although PRL gene is also associated with an increased milk quantity, inverse response over milk composition must be considered in MAS strategy. Our study demonstrated that both LGB and PRL markers could became an advent of MAS utilization in Romanian dairy sheep breeding industry.

  19. Carotenoid production and gene expression in an astaxanthin-overproducing Xanthophyllomyces dendrorhous mutant strain.

    Science.gov (United States)

    Castelblanco-Matiz, Lina M; Barbachano-Torres, Alejandra; Ponce-Noyola, Teresa; Ramos-Valdivia, Ana C; Cerda García-Rojas, Carlos M; Flores-Ortiz, César M; Barahona-Crisóstomo, Salvador K; Baeza-Cancino, Marcelo E; Alcaíno-Gorman, Jennifer; Cifuentes-Guzmán, Víctor H

    2015-12-01

    The primary carotenoid synthesized by Xanthophyllomyces dendrorhous is astaxanthin, which is used as a feed additive in aquaculture. Cell growth kinetics and carotenoid production were correlated with the mRNA levels of the idi, crtE, crtYB, crtI, crtS and crtR genes, and the changes in gene sequence between the wild-type and a carotenoid overproducer XR4 mutant strain were identified. At the late stationary phase, the total carotenoid content in XR4 was fivefold higher than that of the wild-type strain. Additionally, the mRNA levels of crtE and crtS increased during the XR4 growth and were three times higher than the wild-type strain in the late stationary phase. Moreover, the nucleotide sequences of crtYB, crtI and crtR exhibited differences between the strains. Both the higher crtE and crtS transcript levels and the crtYB, crtI and crtR mutations can, at least in part, act to up-regulate the carotenoid biosynthesis pathway in the XR4 strain.

  20. Functional analysis of the Borrelia burgdorferi bba64 gene product in murine infection via tick infestation.

    Directory of Open Access Journals (Sweden)

    Toni G Patton

    Full Text Available Borrelia burgdorferi, the causative agent of Lyme borreliosis, is transmitted to humans from the bite of Ixodes spp. ticks. During the borrelial tick-to-mammal life cycle, B. burgdorferi must adapt to many environmental changes by regulating several genes, including bba64. Our laboratory recently demonstrated that the bba64 gene product is necessary for mouse infectivity when B. burgdorferi is transmitted by an infected tick bite, but not via needle inoculation. In this study we investigated the phenotypic properties of a bba64 mutant strain, including 1 replication during tick engorgement, 2 migration into the nymphal salivary glands, 3 host transmission, and 4 susceptibility to the MyD88-dependent innate immune response. Results revealed that the bba64 mutant's attenuated infectivity by tick bite was not due to a growth defect inside an actively feeding nymphal tick, or failure to invade the salivary glands. These findings suggested there was either a lack of spirochete transmission to the host dermis or increased susceptibility to the host's innate immune response. Further experiments showed the bba64 mutant was not culturable from mouse skin taken at the nymphal bite site and was unable to establish infection in MyD88-deficient mice via tick infestation. Collectively, the results of this study indicate that BBA64 functions at the salivary gland-to-host delivery interface of vector transmission and is not involved in resistance to MyD88-mediated innate immunity.

  1. Heterologous expression of leader-less pga gene in Pichia pastoris: intracellular production of prokaryotic enzyme

    Directory of Open Access Journals (Sweden)

    Kyslík Pavel

    2010-02-01

    Full Text Available Abstract Background Penicillin G acylase of Escherichia coli (PGAEc is a commercially valuable enzyme for which efficient bacterial expression systems have been developed. The enzyme is used as a catalyst for the hydrolytic production of β-lactam nuclei or for the synthesis of semi-synthetic penicillins such as ampicillin, amoxicillin and cephalexin. To become a mature, periplasmic enzyme, the inactive prepropeptide of PGA has to undergo complex processing that begins in the cytoplasm (autocatalytic cleavage, continues at crossing the cytoplasmic membrane (signal sequence removing, and it is completed in the periplasm. Since there are reports on impressive cytosolic expression of bacterial proteins in Pichia, we have cloned the leader-less gene encoding PGAEc in this host and studied yeast production capacity and enzyme authenticity. Results Leader-less pga gene encoding PGAEcunder the control of AOX1 promoter was cloned in Pichia pastoris X-33. The intracellular overproduction of heterologous PGAEc(hPGAEc was evaluated in a stirred 10 litre bioreactor in high-cell density, fed batch cultures using different profiles of transient phases. Under optimal conditions, the average volumetric activity of 25900 U l-1 was reached. The hPGAEc was purified, characterized and compared with the wild-type PGAEc. The α-subunit of the hPGAEc formed in the cytosol was processed aberrantly resulting in two forms with C- terminuses extended to the spacer peptide. The enzyme exhibited modified traits: the activity of the purified enzyme was reduced to 49%, the ratios of hydrolytic activities with cephalexin, phenylacetamide or 6-nitro-3-phenylacetylamidobenzoic acid (NIPAB to penicillin G increased and the enzyme showed a better synthesis/hydrolysis ratio for the synthesis of cephalexin. Conclusions Presented results provide useful data regarding fermentation strategy, intracellular biosynthetic potential, and consequences of the heterologous expression of PGAEc

  2. Gene expression profiling defined pathways correlated with fibroblast cell proliferation induced by Opisthorchis viverrini excretory/secretory product

    Institute of Scientific and Technical Information of China (English)

    Chanitra Thuwajit; Peti Thuwajit; Kazuhiko Uchida; Daoyot Daorueang; Sasithorn Kaewkes; Sopit Wongkham; Masanao Miwa

    2006-01-01

    AIM: To investigate the mechanism of fibroblast cell proliferation stimulated by the Opisthorchis viverrini excretory/secretory (ES) product.METHODS: NIH-3T3, mouse fibroblast cells were treated with O. viverrini ES product by non-contact co-cultured with the adult parasites. Total RNA from NIH-3T3 treated and untreated with O. viverrini was extracted, reverse transcribed and hybridized with the mouse 15K complementary DNA (cDNA) array. The result was analyzed by ArrayVision version 5 and GeneSpring version 5 softwares. After normalization, the ratios of gene expression of parasite treated to untreated NIH3T3 cells of 2-and more-fold upregulated was defined as the differentially expressed genes. The expression levels of the signal transduction genes were validated by semiquantitative SYBR-based real-time RT-PCR.RESULTS: Among a total of 15 000 genes/ESTs, 239genes with established cell proliferation-related function were 2 fold-and more-up-regulated by O. viverrini ES product compared to those in cells without exposure to the parasitic product. These genes were classified into groups including energy and metabolism, signal transduction, protein synthesis and translation, matrix and structural protein, transcription control, cell cycle and DNA replication. Moreover, the expressions of serinethreonine kinase receptor, receptor tyrosine kinase and collagen production-related genes were up-regulated by O. viverrini ES product. The expression level of signal transduction genes; pkC, pdgfrα, jak 1, eps 8, tgfβ 1/4,strap and h ras measured by real-time RT-PCR confirmed their expression levels to those obtained from cDNA array. However, only the up-regulated expression of pkC, eps 8 and tgfβ 1/4 which are the downstream signaling molecules of either epidermal growth factor (EGF) or transforming growth factor-β (TGF-β) showed statistical significance (P < 0.05). CONCLUSION: O. viverrini ES product stimulates the significant changes of gene expression in several

  3. Functional assessment of plant and microalgal lipid pathway genes in yeast to enhance microbial industrial oil production.

    Science.gov (United States)

    Peng, Huadong; Moghaddam, Lalehvash; Brinin, Anthony; Williams, Brett; Mundree, Sagadevan; Haritos, Victoria S

    2017-06-25

    As promising alternatives to fossil-derived oils, microbial lipids are important as industrial feedstocks for biofuels and oleochemicals. Our broad aim is to increase lipid content in oleaginous yeast through expression of lipid accumulation genes and use Saccharomyces cerevisiae to functionally assess genes obtained from oil-producing plants and microalgae. Lipid accumulation genes DGAT (diacylglycerol acyltransferase), PDAT (phospholipid: diacylglycerol acyltransferase), and ROD1 (phosphatidylcholine: diacylglycerol choline-phosphotransferase) were separately expressed in yeast and lipid production measured by fluorescence, solvent extraction, thin layer chromatography, and gas chromatography (GC) of fatty acid methyl esters. Expression of DGAT1 from Arabidopsis thaliana effectively increased total fatty acids by 1.81-fold above control, and ROD1 led to increased unsaturated fatty acid content of yeast lipid. The functional assessment approach enabled the fast selection of candidate genes for metabolic engineering of yeast for production of lipid feedstocks. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

  4. Association of bGH and Pit-1 gene variants with milk production traits in dairy Gyr bulls

    Directory of Open Access Journals (Sweden)

    Mattos Keiko Kusamura de

    2004-01-01

    Full Text Available The objective of this study was to obtain genetic marker information in the Gyr breed by analyzing bGH and Pit-1 gene polymorphisms and to verify their association with milk production traits. One sample including 40 Gyr bulls were genotyped at two bGH gene restriction sites (bGH- AluI and bGH-MspI and at one restriction site in the Pit-1 gene (Pit-1 HinfI. The bGH-MspI(- allele was favorable for fat milk percentage. The heterozigous Pit-1 HinfI (+/- bulls were superior for fat milk production, in relation to homozigous Pit-1 HinfI (+/+. The Pit-1 and bGH genes are strong candidates in the dairy cattle QTL search, and zebuine populations are promising samples for this purpose.

  5. Production of β-ionone by combined expression of carotenogenic and plant CCD1 genes in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Lopez, Javiera; Essus, Karen; Kim, Il-Kwon

    2015-01-01

    cells. The additional integration of the carotenoid cleavage dioxygenase gene from the plant Petunia hybrida (PhCCD1) let to the production of low amounts of beta-ionone (0.073 ± 0.01 mg/g DCW) and changed the color of the strain from orange to yellow. The expression of the crtYB gene from a high copy......, apocarotenoids have high commercial value for the cosmetic and food industry, but currently their production is mainly assured by chemical synthesis. In the present study, a Saccharomyces cerevisiae strain that synthesizes the apocarotenoid β-ionone was constructed by combining integrative vectors and high copy...... number episomal vectors, in an engineered strain that accumulates FPP. Results: Integration of an extra copy of the geranylgeranyl diphosphate synthase gene (BTS1), together with the carotenogenic genes crtYB and crtI from the ascomycete Xanthophyllomyces dendrorhous, resulted in carotenoid producing...

  6. Isolation of Penicillium nalgiovense strains impaired in penicillin production by disruption of the pcbAB gene and application as starters on cured meat products.

    Science.gov (United States)

    Laich, Federico; Fierro, Francisco; Martin, Juan F

    2003-06-01

    The presence of some fungi on a variety of food products, like cheeses or cured meat products, is beneficial for the ripening of the product and for the development of specific flavour features. The utilization of these fungi as starters, which are inoculated normally as asexual spores on the food products at the beginning of the ripening process, is becoming a usual procedure in the food industry. The starter culture also prevents undesirable fungi or bacteria from growing on the product. Penicillium nalgiovense is the most frequently used starter for cured and fermented meat products, but the fact that this fungus can secrete penicillin to the meat product makes it important to get strains unable to synthesize this antibiotic. In this work we report that P. nalgiovense strains impaired in penicillin production can be obtained by disruption of the pcbAB gene (the first gene of the penicillin biosynthetic pathway). When applied as starter on cecina (a salted, smoke-cured beef meat product from the region of León, Spain), the pcbAB-disrupted strain showed no differences with respect to the parental penicillin-producing strain in its ability to colonize the meat pieces and to control their normal mycoflora. Both strains exerted a similar control on the presence of bacteria in cecina. A similar proportion of penicillin-sensitive and penicillin-resistant bacteria were isolated from pieces inoculated with the penicillin-producing or the non-producing P. nalgiovense strains. The decrease of the bacterial population on the surface of cecina seems to be due to the higher competition for nutrients as a consequence of the inoculation and development of the P. nalgiovense mycelium and not due to the production of penicillin by this fungus. Penicillin production was less affected than growth in a solid medium with high NaCl concentrations; this suggests that the high salt concentration present in cecina is not a limiting factor for penicillin production by P. nalgiovense.

  7. The early gene product EUO is a transcriptional repressor that selectively regulates promoters of Chlamydia late genes.

    Science.gov (United States)

    Rosario, Christopher J; Tan, Ming

    2012-06-01

    The obligate intracellular bacterium Chlamydia has an unusual developmental cycle in which there is conversion between two forms that are specialized for either intracellular replication or propagation of the infection to a new host cell. Expression of late chlamydial genes is upregulated during conversion from the replicating to the infectious form, but the mechanism for this temporal regulation is unknown. We found that EUO, which is expressed from an early gene, binds to two sites upstream of the late operon omcAB, but only the downstream site was necessary for transcriptional repression. Using gel shift and in vitro transcription assays we showed that EUO specifically bound and repressed promoters of Chlamydia trachomatis late genes, but not early or mid genes. These findings support a role for EUO as a temporal repressor that negatively regulates late chlamydial genes and prevents their premature expression. The basis of this specificity is the ability of EUO to selectively bind promoter regions of late genes, which would prevent their transcription by RNA polymerase. Thus, we propose that EUO is a master regulator that prevents the terminal differentiation of the replicating form of chlamydiae into the infectious form until sufficient rounds of replication have occurred.

  8. The SMUL_1544 Gene Product Governs Norcobamide Biosynthesis in the Tetrachloroethene-Respiring Bacterium Sulfurospirillum multivorans.

    Science.gov (United States)

    Keller, Sebastian; Treder, Aaron; von Reuss, Stephan H; Escalante-Semerena, Jorge C; Schubert, Torsten

    2016-08-15

    The tetrachloroethene (PCE)-respiring bacterium Sulfurospirillum multivorans produces a unique cobamide, namely, norpseudo-B12, which, in comparison to other cobamides, e.g., cobalamin and pseudo-B12, lacks the methyl group in the linker moiety of the nucleotide loop. In this study, the protein SMUL_1544 was shown to be responsible for the formation of the unusual linker moiety, which is most probably derived from ethanolamine-phosphate (EA-P) as the precursor. The product of the SMUL_1544 gene successfully complemented a Salmonella enterica ΔcobD mutant. The cobD gene encodes an l-threonine-O-3-phosphate (l-Thr-P) decarboxylase responsible for the synthesis of (R)-1-aminopropan-2-ol O-2-phosphate (AP-P), required specifically for cobamide biosynthesis. When SMUL_1544 was produced in the heterologous host lacking CobD, norpseudo-B12 was formed, which pointed toward the formation of EA-P rather than AP-P. Guided cobamide biosynthesis experiments with minimal medium supplemented with l-Thr-P supported cobamide biosynthesis in S. enterica producing SMUL_1544 or S. multivorans Under these conditions, both microorganisms synthesized pseudo-B12 This observation indicated a flexibility in the SMUL_1544 substrate spectrum. From the formation of catalytically active PCE reductive dehalogenase (PceA) in S. multivorans cells producing pseudo-B12, a compatibility of the respiratory enzyme with the cofactor was deduced. This result might indicate a structural flexibility of PceA in cobamide binding. Feeding of l-[3-(13)C]serine to cultures of S. multivorans resulted in isotope labeling of the norpseudo-B12 linker moiety, which strongly supports the hypothesis of EA-P formation from l-serine-O-phosphate (l-Ser-P) in this organism. The identification of the gene product SMUL_1544 as a putative l-Ser-P decarboxylase involved in norcobamide biosynthesis in S. multivorans adds a novel module to the assembly line of cobamides (complete corrinoids) in prokaryotes. Selected cobamide

  9. Association between the enterotoxin production and presence of Coa, Nuc genes among Staphylococcus aureus isolated from various sources, in Shiraz

    OpenAIRE

    Moghassem Hamidi, R; Hosseinzadeh, S; Shekarforoush, S. S.; Poormontaseri, M; Derakhshandeh, A

    2015-01-01

    The present study was aimed to identify the frequency of coagulase (Coa) and thermonuclease (Nuc) genes and Staphylococcal enterotoxin A (Sea) production among Staphylococcus aureus isolated from various sources in Shiraz. Moreover, the correlation between the Sea gene and coagulase and thermonuclease enzymes is also considered. A total of 100 S. aureus were isolated from various sources including 40 humans, 30 animals and 30 food samples by the routine biochemical tests. The frequency of Coa...

  10. A lentiviral gene therapy strategy for the in vitro production of feline erythropoietin.

    Directory of Open Access Journals (Sweden)

    Natalia Vapniarsky

    Full Text Available Nonregenerative anemia due to chronic renal failure is a common problem in domestic cats. Unfortunately, administration of recombinant human erythropoietin often only improves anemia temporarily due to antibody development. In this in vitro study, feline erythropoietin cDNA was cloned from feline renal tissue and utilized in the construction of a replication-defective lentiviral vector. The native recombinant feline erythropoietin (rfEPO sequence was confirmed by sequencing. Upon viral vector infection of human 293H cells, Crandall Renal Feline Kidney cell line and primary feline peripheral blood mononuclear cells, bioactive rfEPO protein was produced. The presence of cellular rfEPO cDNA was confirmed by standard PCR, production of abundant rfEPO mRNA was confirmed by real-time PCR, and secretion of rfEPO protein was demonstrated by Western blot analyses, while rfEPO protein bioactivity was confirmed via an MTT proliferation bioassay. This in vitro study demonstrates the feasibility of a replication-defective lentiviral vector delivery system for the in vitro production of biologically active feline erythropoietin. Anemic cats with chronic renal failure represent a potential in vivo application of a lentiviral gene therapy system.

  11. Early Determination of Animals with Favorable Genes in Milk Production for Profitable Private Farms

    Directory of Open Access Journals (Sweden)

    Daniela E. Ilie

    2010-05-01

    Full Text Available The primary goal of dairy industry has been to identify an efficient and economical way of increasing milk production and its constituents without increasing the size of the dairy herd. The use of milk protein polymorphisms as detectable molecular markers has been studied intensively because of their effect on the yield and processing properties of milk and its products. Thus, molecular markers are promising alternative to the current methods of trait selection once these genes are proven to be associated with traits of interest in animals. Kappa-casein (CSN3 and beta-lactoglobulin (BLG are two of the most important proteins in the milk of mammals that play a crucial role in the milk quality and coagulation, an essential process for cheese and butter. The A and B variant of k-casein and β-lactoglobulin were distinguished by Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP analysis in 108 Romanian Simmental and 60 Holstein Friesian cattle.

  12. Genes influencing milk production traits predominantly affect one of four biological pathways

    Directory of Open Access Journals (Sweden)

    Goddard Michael

    2008-01-01

    Full Text Available Abstract In this study we introduce a method that accounts for false positive and false negative results in attempting to estimate the true proportion of quantitative trait loci that affect two different traits. This method was applied to data from a genome scan that was used to detect QTL for three independent milk production traits, Australian Selection Index (ASI, protein percentage (P% and fat percentage corrected for protein percentage (F% – P%. These four different scenarios are attributed to four biological pathways: QTL that (1 increase or decrease total mammary gland production (affecting ASI only; (2 increase or decrease lactose synthesis resulting in the volume of milk being changed but without a change in protein or fat yield (affecting P% only; (3 increase or decrease protein synthesis while milk volume remains relatively constant (affecting ASI and P% in the same direction; (4 increase or decrease fat synthesis while the volume of milk remains relatively constant (affecting F% – P% only. The results indicate that of the positions that detected a gene, most affected one trait and not the others, though a small proportion (2.8% affected ASI and P% in the same direction.

  13. Mapping gene clusters within arrayed metagenomic libraries to expand the structural diversity of biomedically relevant natural products.

    Science.gov (United States)

    Owen, Jeremy G; Reddy, Boojala Vijay B; Ternei, Melinda A; Charlop-Powers, Zachary; Calle, Paula Y; Kim, Jeffrey H; Brady, Sean F

    2013-07-16

    Complex microbial ecosystems contain large reservoirs of unexplored biosynthetic diversity. Here we provide an experimental framework and data analysis tool to facilitate the targeted discovery of natural-product biosynthetic gene clusters from the environment. Multiplex sequencing of barcoded PCR amplicons is followed by sequence similarity directed data parsing to identify sequences bearing close resemblance to biosynthetically or biomedically interesting gene clusters. Amplicons are then mapped onto arrayed metagenomic libraries to guide the recovery of targeted gene clusters. When applied to adenylation- and ketosynthase-domain amplicons derived from saturating soil DNA libraries, our analysis pipeline led to the recovery of biosynthetic clusters predicted to encode for previously uncharacterized glycopeptide- and lipopeptide-like antibiotics; thiocoraline-, azinomycin-, and bleomycin-like antitumor agents; and a rapamycin-like immunosuppressant. The utility of the approach is demonstrated by using recovered eDNA sequences to generate glycopeptide derivatives. The experiments described here constitute a systematic interrogation of a soil metagenome for gene clusters capable of encoding naturally occurring derivatives of biomedically relevant natural products. Our results show that previously undetected biosynthetic gene clusters with potential biomedical relevance are very common in the environment. This general process should permit the routine screening of environmental samples for gene clusters capable of encoding the systematic expansion of the structural diversity seen in biomedically relevant families of natural products.

  14. Scanning for genes in large genomic regions: cosmid-based exon trapping of multiple exons in a single product.

    Science.gov (United States)

    Datson, N A; van de Vosse, E; Dauwerse, H G; Bout, M; van Ommen, G J; den Dunnen, J T

    1996-03-15

    To facilitate the scanning of large genomic regions for the presence of exonic gene segments we have constructed a cosmid-based exon trap vector. The vector serves a dual purpose since it is also suitable for contig construction and physical mapping. The exon trap cassette of vector sCOGH1 consists of the human growth hormone gene driven by the mouse mettallothionein-1 promoter. Inserts are cloned in the multicloning site located in intron 2 of the hGH gene. The efficiency of the system is demonstrated with cosmids containing multiple exons of the Duchenne Muscular Dystrophy gene. All exons present in the inserts were successfully retrieved and no cryptic products were detected. Up to seven exons were isolated simultaneously in a single spliced product. The system has been extended by a transcription-translation-test protocol to determine the presence of large open reading frames in the trapped products, using a combination of tailed PCR primers directing protein synthesis in three different reading frames, followed by in vitro transcription-translation. Having larger stretches of coding sequence in a single exon trap product rather than small single exons greatly facilitates further analysis of potential genes and offers new possibilities for direct mutation analysis of exon trap material.

  15. Norepinephrine causes epigenetic repression of PKCε gene in rodent hearts by activating Nox1-dependent reactive oxygen species production.

    Science.gov (United States)

    Xiong, Fuxia; Xiao, Daliao; Zhang, Lubo

    2012-07-01

    Heart disease is the leading cause of death in the United States. Recent studies demonstrate that fetal programming of PKCε gene repression results in ischemia-sensitive phenotype in the heart. The present study tests the hypothesis that increased norepinephrine causes epigenetic repression of PKCε gene in the heart via Nox1-dependent reactive oxygen species (ROS) production. Prolonged norepinephrine treatment increased ROS production in fetal rat hearts and embryonic ventricular myocyte H9c2 cells via a selective increase in Nox1 expression. Norepinephrine-induced ROS resulted in an increase in PKCε promoter methylation at Egr-1 and Sp-1 binding sites, leading to PKCε gene repression. N-acetylcysteine, diphenyleneiodonium, and apocynin blocked norepinephrine-induced ROS production and the promoter methylation, and also restored PKCε mRNA and protein to control levels in vivo in fetal hearts and in vitro in embryonic myocyte cells. Accordingly, norepinephrine-induced ROS production, promoter methylation, and PKCε gene repression were completely abrogated by knockdown of Nox1 in cardiomyocytes. These findings provide evidence of a novel interaction between elevated norepinephrine and epigenetic repression of PKCε gene in the heart mediated by Nox1-dependent oxidative stress and suggest new insights of molecular mechanisms linking the heightened sympathetic activity to aberrant cardioprotection and increased ischemic vulnerability in the heart.

  16. Cloning of the hexA mismatch-repair gene of Streptococcus pneumoniae and identification of the product.

    Science.gov (United States)

    Martin, B; Prats, H; Claverys, J P

    1985-01-01

    The hexA mismatch repair gene of Streptococcus pneumoniae has been cloned into multicopy plasmid vectors. The cloned hexA gene is expressed as judged from its ability to complement various chromosomal hexA- alleles. Its direction of transcription was defined and the functional limits were localized by original methods relying on homology-dependent integration of nonautonomous chimeric plasmids carrying chromosomal inserts into the chromosome. Comparison of the proteins encoded by recombinant plasmids and by restriction fragments allowed us to identify an Mr 94 000 protein as the probable product of the hexA gene.

  17. Association of bGH and Pit-1 gene variants with milk production traits in dairy Gyr bulls.

    OpenAIRE

    Mattos Keiko Kusamura de; Del Lama Silvia Nassif; Martinez Mario Luiz; Freitas Ary Ferreira de

    2004-01-01

    The objective of this study was to obtain genetic marker information in the Gyr breed by analyzing bGH and Pit-1 gene polymorphisms and to verify their association with milk production traits. One sample including 40 Gyr bulls were genotyped at two bGH gene restriction sites (bGH- AluI and bGH-MspI) and at one restriction site in the Pit-1 gene (Pit-1 HinfI). The bGH-MspI(-) allele was favorable for fat milk percentage. The heterozigous Pit-1 HinfI (+/-) bulls were superior for fat milk produ...

  18. Enhanced production of shikimic acid using a multi-gene co-expression system in Escherichia coli.

    Science.gov (United States)

    Liu, Xiang-Lei; Lin, Jun; Hu, Hai-Feng; Zhou, Bin; Zhu, Bao-Quan

    2016-04-01

    Shikimic acid (SA) is the key synthetic material for the chemical synthesis of Oseltamivir, which is prescribed as the front-line treatment for serious cases of influenza. Multi-gene expression vector can be used for expressing the plurality of the genes in one plasmid, so it is widely applied to increase the yield of metabolites. In the present study, on the basis of a shikimate kinase genetic defect strain Escherichia coli BL21 (ΔaroL/aroK, DE3), the key enzyme genes aroG, aroB, tktA and aroE of SA pathway were co-expressed and compared systematically by constructing a series of multi-gene expression vectors. The results showed that different gene co-expression combinations (two, three or four genes) or gene orders had different effects on the production of SA. SA production of the recombinant BL21-GBAE reached to 886.38 mg·L(-1), which was 17-fold (P < 0.05) of the parent strain BL21 (ΔaroL/aroK, DE3).

  19. Dynamics of plc gene transcription and α-toxin production during growth of Clostridium perfringens strains with contrasting α-toxin production

    DEFF Research Database (Denmark)

    Abildgaard, Lone; Schramm, Andreas; Rudi, Knut

    2009-01-01

    The aim of the present study was to investigate transcription dynamics of the α-toxin-encoding plc gene relative to two housekeeping genes (gyrA and rplL) in batch cultures of three Clostridium perfringens strains with low, intermediate, and high levels of α-toxin production, respectively. The plc...... transcript level was always low in the low α-toxin producing strain. For the two other strains, plc transcription showed an inducible pattern and reached a maximum level in the late exponential growth phase. The transcription levels were however inversely correlated to α-toxin production for the two strains....... We propose that this discrepancy is due to differences in plc translation rates between the strains and that strain-specific translational rates therefore must be determined before α-toxin production can be extrapolated from transcript levels in C. perfringens....

  20. Identification of the nahR gene product and nucleotide sequences required for its activation of the sal operon.

    OpenAIRE

    1986-01-01

    The product of the nahR gene, a salicylate-dependent activator of transcription of the nah and sal hydrocarbon degradation operons of the NAH7 plasmid, was identified and characterized after synthesis in Escherichia coli maxicells. The nahR gene product had a subunit molecular weight of 36,000, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, whereas gel filtration analysis of the nondenatured nahR protein indicated a molecular weight in excess of 250,000. However, ...

  1. High-level production of beta-carotene in Saccharomyces cerevisiae by successive transformation with carotenogenic genes from Xanthophyllomyces dendrorhous.

    Science.gov (United States)

    Verwaal, René; Wang, Jing; Meijnen, Jean-Paul; Visser, Hans; Sandmann, Gerhard; van den Berg, Johan A; van Ooyen, Albert J J

    2007-07-01

    To determine whether Saccharomyces cerevisiae can serve as a host for efficient carotenoid and especially beta-carotene production, carotenogenic genes from the carotenoid-producing yeast Xanthophyllomyces dendrorhous were introduced and overexpressed in S. cerevisiae. Because overexpression of these genes from an episomal expression vector resulted in unstable strains, the genes were integrated into genomic DNA to yield stable, carotenoid-producing S. cerevisiae cells. Furthermore, carotenoid production levels were higher in strains containing integrated carotenogenic genes. Overexpression of crtYB (which encodes a bifunctional phytoene synthase and lycopene cyclase) and crtI (phytoene desaturase) from X. dendrorhous was sufficient to enable carotenoid production. Carotenoid production levels were increased by additional overexpression of a homologous geranylgeranyl diphosphate (GGPP) synthase from S. cerevisiae that is encoded by BTS1. Combined overexpression of crtE (heterologous GGPP synthase) from X. dendrorhous with crtYB and crtI and introduction of an additional copy of a truncated 3-hydroxy-3-methylglutaryl-coenzyme A reductase gene (tHMG1) into carotenoid-producing cells resulted in a successive increase in carotenoid production levels. The strains mentioned produced high levels of intermediates of the carotenogenic pathway and comparable low levels of the preferred end product beta-carotene, as determined by high-performance liquid chromatography. We finally succeeded in constructing an S. cerevisiae strain capable of producing high levels of beta-carotene, up to 5.9 mg/g (dry weight), which was accomplished by the introduction of an additional copy of crtI and tHMG1 into carotenoid-producing yeast cells. This transformant is promising for further development toward the biotechnological production of beta-carotene by S. cerevisiae.

  2. The loose evolutionary relationships between transcription factors and other gene products across prokaryotes

    OpenAIRE

    del Grande, Marc; Moreno-Hagelsieb, Gabriel

    2014-01-01

    Background Tests for the evolutionary conservation of associations between genes coding for transcription factors (TFs) and other genes have been limited to a few model organisms due to the lack of experimental information of functional associations in other organisms. We aimed at surmounting this limitation by using the most co-occurring gene pairs as proxies for the most conserved functional interactions available for each gene in a genome. We then used genes predicted to code for TFs to co...

  3. Expression of genes responsible for ethylene production and wilting are differently regulated in carnation (Dianthus caryophyllus L.) petals.

    Science.gov (United States)

    Kosugi; Shibuya; Tsuruno; Iwazaki; Mochizuki; Yoshioka; Hashiba; Satoh

    2000-09-01

    Carnation petals exhibit autocatalytic ethylene production and wilting during senescence. The autocatalytic ethylene production is caused by the expression of 1-aminocyclopropane-1-carboxylate (ACC) synthase and ACC oxidase genes, whereas the wilting of petals is related to the expression of the cysteine proteinase (CPase) gene. So far, it has been believed that the ethylene production and wilting are regulated in concert in senescing carnation petals, since the two events occurred closely in parallel with time. In the present study, we investigated the expression of these genes in petals of a transgenic carnation harboring a sense ACC oxidase transgene and in petals of carnation flowers treated with 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS). In petals of the transgenic carnation flowers, treatment with exogenous ethylene caused accumulation of the transcript for CPase and in-rolling (wilting), whereas it caused no or little accumulation of the transcripts for ACC oxidase and ACC synthase and negligible ethylene production. In petals of the flowers treated with DPSS, the transcripts for ACC synthase and ACC oxidase were accumulated, but no significant change in the level of the transcript for CPase was observed. These results suggest that the expression of ACC synthase and ACC oxidase genes, which leads to ethylene production, is differentially regulated from the expression of CPase, which leads to wilting, in carnation petals.

  4. Cloning and verification of the Lactococcus lactis pyrG gene and characterization of the gene product, CTP synthase

    DEFF Research Database (Denmark)

    Wadskov-Hansen, Steen Lyders Lerche; Willemoës, M.; Martinussen, Jan

    2001-01-01

    The pyrG gene of Lactococcus lactis subsp. cremoris, encoding CTP synthase, has been cloned and sequenced. It is flanked upstream by an open reading frame showing homology to several aminotransferases and downstream by an open reading frame of unknown function. L. lactis strains harboring disrupted...... of a functional cdd gene encoding cytidine deaminase. A characterization of the enzyme revealed similar properties as found for CTP synthases from other organisms. However, unlike the majority of CTP synthases the lactococcal enzyme can convert dUTP to dCTP, although a half saturation concentration of 0.6 m...

  5. The Regulatory Pathway for Advanced Cell Therapy and Gene Therapy Products in Brazil: A Road to Be Built.

    Science.gov (United States)

    de Freitas, Daniel Roberto Coradi

    2015-01-01

    The regulation of cell therapy and gene therapy products is a major challenge for the Brazilian state. From a legal point of view, the legislative apparatus, including constitutional, prohibits the marketing and patent of human substances. From the point of view of the organization of the state bureaucracy, the responsibilities for the regulation of research and application of these technologies in humans may involve up to four different institutions. The National Agency for Health Surveillance (ANVISA) has been the protagonist in structuring the regulation of cell therapy and gene therapy in Brazil, and steps have been taken to ensure quality of these products. However, obstacles such as the commercialization of these therapies and the need to determine whether these products will be regulated following the assumptions adopted in Brazil for drugs and biological products or for human blood and tissues still remain.

  6. Identification of the Genes Involved in the Fruiting Body Production and Cordycepin Formation of Cordyceps militaris Fungus

    Science.gov (United States)

    Zheng, Zhuang-li; Qiu, Xue-hong

    2015-01-01

    A mutant library of Cordyceps militaris was constructed by improved Agrobacterium tumefaciens-mediated transformation and screened for degradation features. Six mutants with altered characters in in vitro and in vivo fruiting body production, and cordycepin formation were found to contain a single copy T-DNA. T-DNA flanking sequences of these mutants were identified by thermal asymmetric interlaced-PCR approach. ATP-dependent helicase, cytochrome oxidase subunit I and ubiquitin-like activating enzyme were involved in in vitro fruiting body production, serine/threonine phosphatase involved in in vivo fruiting body production, while glucose-methanol-choline oxidoreductase and telomerase reverse transcriptase involved in cordycepin formation. These genes were analyzed by bioinformatics methods, and their molecular function and biology process were speculated by Gene Ontology (GO) analysis. The results provided useful information for the control of culture degeneration in commercial production of C. militaris. PMID:25892913

  7. Cloning of affecting pyruvate decarboxylase gene in the production bioethanol of agricultural waste in the E.coli bacteria

    Directory of Open Access Journals (Sweden)

    Masome Zeinali

    2016-09-01

    Full Text Available Introduction: Ethanol made by a biomass is one of the useful strategies in terms of economic and environmental and as a clean and safe energy to replace fossil fuels considered and examined. Materials and methods: In this study, key enzyme in the production of ethanol (Pyruvate decarboxylase from Zymomonas mobilis bacteria was isolated and cloned at E. coli bacteria by freeze and thaw method. For gene cloning, we used specific primers of pdc and PCR reaction and then pdc gene isolated and pET 28a plasmid double digested with (Sal I and Xho I enzymes. Digestion Products were ligated by T4 DNA ligase in 16 °C for 16 hours. Results: Results of bacteria culture showed that a few colonies containing pET 28a plasmid could grow. Result of colony pcr of pdc gene with specific primers revealed 1700 bp bands in 1% agarose gel electrophoresis. The results of PCR with T7 promotor forward primer and pdc revers primer have proved the accurate direction of integration of pdc gene into plasmid and revealed 1885 bp band. Double digestion of recombinant plasmid with SalI and XhoI enzymes revealed same bands. Finally, RT showed the expected band of 1700 bp that implies the desired gene expression in the samples. Discussion and conclusion: Due to the increased production of ethanol via pyruvate decarboxylase gene cloning in expression plasmids with a strong promoter upstream of the cloning site can conclude that, pyruvate decarboxylase cloning as a key gene would be useful and according to beneficial properties of E. coli bacteria, transfering the gene to bacteria appears to be reasonable.

  8. Mycobacterial tlyA gene product is localized to cell-wall without signal sequence.

    Directory of Open Access Journals (Sweden)

    Santosh eKumar

    2015-08-01

    Full Text Available The mycobacterial tlyA gene product, Rv1694 (MtbTlyA, has been annotated as 'hemolysin' which was re-annotated as 2'-O rRNA methyl transferase. In order to function as a hemolysin, it must reach extracellular milieu with the help of signal sequence(s and/or transmembrane segment(s. However, the MtbTlyA neither has classical signals sequences that signify general/Sec/Tat pathways nor transmembrane segments. Interestingly, the tlyA gene appears to be restricted to pathogenic strains such as H37Rv, M. marinum, M. leprae, than M. smegmatis, M. vaccae, M. kansasii etc., which highlights the need for a detailed investigation to understand its functions. In this study, we have provided several evidences which highlight the presence of TlyA on the surface of M. marinum (native host and upon expression in M. smegmatis (surrogate host and E. coli (heterologous host. The TlyA was visualized at the bacterial-surface by confocal microscopy and accessible to Proteinase K. In addition, sub-cellular fractionation has revealed the presence of TlyA in the membrane fractions and this sequestration is not dependent on TatA, TatC or SecA2 pathways. As a consequence of expression, the recombinant bacteria exhibit distinct hemolysis. Interestingly, the MtbTlyA was also detected in both membrane vesicles secreted by M. smegmatis and outer membrane vesicles secreted by E. coli. Our experimental evidences unambiguously confirm that the mycobacterial TlyA can reach the extra cellular milieu without any signal sequence. Hence, the localization of TlyA class of proteins at the bacterial surface may highlight the existence of non-classical bacterial secretion mechanisms.

  9. Experimental Model to Study the Role of Retinoblastoma Gene Product (pRb) for Determination of Adipocyte Differentiation.

    Science.gov (United States)

    Popov, B V; Shilo, P S; Zhidkova, O V; Zaichik, A M; Petrov, N S

    2015-06-01

    Using stable constitutive expression of retinoblastoma gene product (pRb) in polypotent mesenchymal 10T1/2 cells we obtained stable cell lines hyperexpressing functionally active or inactive mutant pRb. The cells producing active exogenous pRb demonstrated high sensitivity to adipocyte differentiation inductors, whereas production of inactive form of the exogenous protein suppressed adipocyte differentiation. The obtained lines can serve as the experimental model for studying the role of pRb in determination of adipocyte differentiation.

  10. The spliced BZLF1 gene of Epstein-Barr virus (EBV) transactivates an early EBV promoter and induces the virus productive cycle.

    OpenAIRE

    1989-01-01

    A spliced cDNA spanning the Epstein-Barr virus BZLF1 gene expresses the BZLF1 protein and is active in inducing the virus productive cycle. A deletion mutant which lacks the N-terminal half of the protein is inactive. Cotransfection experiments in EBV-negative B-lymphocyte cell lines demonstrated that the BZLF1 gene activates the promoter for the BSLF2 + BMLF1 gene in the absence of any other EBV gene product. These results confirmed that the spliced BZLF1 gene is the transactivating gene str...

  11. Mosaics of gene variations in the Interleukin-10 gene promoter affect interleukin-10 production depending on the stimulation used.

    NARCIS (Netherlands)

    Mormann, M.; Rieth, H.; Hua, T.D.; Assohou-Luty, C.A.; Roupelieva, M.; Hu, S.L.; Kremsner, P.G.; Luty, J.F.; Kube, D.

    2004-01-01

    Interleukin-10 (IL-10), a cytokine involved in many aspects of the immune response shows interindividual variations in their expression. However, genetic variations of the 5'-flanking region of the IL-10 gene (PIL-10) are poorly characterised with respect to different stimuli. New extended haplo-

  12. Mosaics of gene variations in the Interleukin-10 gene promoter affect interleukin-10 production depending on the stimulation used.

    NARCIS (Netherlands)

    Mormann, M.; Rieth, H.; Hua, T.D.; Assohou-Luty, C.A.; Roupelieva, M.; Hu, S.L.; Kremsner, P.G.; Luty, J.F.; Kube, D.

    2004-01-01

    Interleukin-10 (IL-10), a cytokine involved in many aspects of the immune response shows interindividual variations in their expression. However, genetic variations of the 5'-flanking region of the IL-10 gene (PIL-10) are poorly characterised with respect to different stimuli. New extended haplo- an

  13. Pistil Transcriptome Analysis to Disclose Genes and Gene Products Related to Aposporous Apomixis in Hypericum perforatum L.

    Science.gov (United States)

    Galla, Giulio; Zenoni, Sara; Avesani, Linda; Altschmied, Lothar; Rizzo, Paride; Sharbel, Timothy F; Barcaccia, Gianni

    2017-01-01

    Unlike sexual reproduction, apomixis encompasses a number of reproductive strategies, which permit maternal genome inheritance without genetic recombination and syngamy. The key biological features of apomixis are the circumvention of meiosis (i.e., apomeiosis), the differentiation of unreduced embryo sacs and egg cells, and their autonomous development in functional embryos through parthenogenesis, and the formation of viable endosperm either via fertilization-independent means or following fertilization with a sperm cell. Despite the importance of apomixis for breeding of crop plants and although much research has been conducted to study this process, the genetic control of apomixis is still not well understood. Hypericum perforatum is becoming an attractive model system for the study of aposporous apomixis. Here we report results from a global gene expression analysis of H. perforatum pistils collected from sexual and aposporous plant accessions for the purpose of identifying genes, biological processes and molecular functions associated with the aposporous apomixis pathway. Across two developmental stages corresponding to the expression of aposporous apomeiosis and parthenogenesis in ovules, a total of 224 and 973 unigenes were found to be significantly up- and down-regulated with a fold change ≥ 2 in at least one comparison, respectively. Differentially expressed genes were enriched for multiple gene ontology (GO) terms, including cell cycle, DNA metabolic process, and single-organism cellular process. For molecular functions, the highest scores were recorded for GO terms associated with DNA binding, DNA (cytosine-5-)-methyltransferase activity and heterocyclic compound binding. As deregulation of single components of the sexual developmental pathway is believed to be a trigger of the apomictic reproductive program, all genes involved in sporogenesis, gametogenesis and response to hormonal stimuli were analyzed in great detail. Overall, our data suggest that

  14. Pistil Transcriptome Analysis to Disclose Genes and Gene Products Related to Aposporous Apomixis in Hypericum perforatum L.

    Science.gov (United States)

    Galla, Giulio; Zenoni, Sara; Avesani, Linda; Altschmied, Lothar; Rizzo, Paride; Sharbel, Timothy F.; Barcaccia, Gianni

    2017-01-01

    Unlike sexual reproduction, apomixis encompasses a number of reproductive strategies, which permit maternal genome inheritance without genetic recombination and syngamy. The key biological features of apomixis are the circumvention of meiosis (i.e., apomeiosis), the differentiation of unreduced embryo sacs and egg cells, and their autonomous development in functional embryos through parthenogenesis, and the formation of viable endosperm either via fertilization-independent means or following fertilization with a sperm cell. Despite the importance of apomixis for breeding of crop plants and although much research has been conducted to study this process, the genetic control of apomixis is still not well understood. Hypericum perforatum is becoming an attractive model system for the study of aposporous apomixis. Here we report results from a global gene expression analysis of H. perforatum pistils collected from sexual and aposporous plant accessions for the purpose of identifying genes, biological processes and molecular functions associated with the aposporous apomixis pathway. Across two developmental stages corresponding to the expression of aposporous apomeiosis and parthenogenesis in ovules, a total of 224 and 973 unigenes were found to be significantly up- and down-regulated with a fold change ≥ 2 in at least one comparison, respectively. Differentially expressed genes were enriched for multiple gene ontology (GO) terms, including cell cycle, DNA metabolic process, and single-organism cellular process. For molecular functions, the highest scores were recorded for GO terms associated with DNA binding, DNA (cytosine-5-)-methyltransferase activity and heterocyclic compound binding. As deregulation of single components of the sexual developmental pathway is believed to be a trigger of the apomictic reproductive program, all genes involved in sporogenesis, gametogenesis and response to hormonal stimuli were analyzed in great detail. Overall, our data suggest that

  15. A post-GWAS replication study confirming the PTK2 gene associated with milk production traits in Chinese Holstein.

    Science.gov (United States)

    Wang, Haifei; Jiang, Li; Liu, Xuan; Yang, Jie; Wei, Julong; Xu, Jingen; Zhang, Qin; Liu, Jian-Feng

    2013-01-01

    Our initial genome-wide association study (GWAS) demonstrated that two SNPs (ARS-BFGL-NGS-33248, UA-IFASA-9288) within the protein tyrosine kinase 2 (PTK2) gene were significantly associated with milk production traits in Chinese Holstein dairy cattle. To further validate if the statistical evidence provided in GWAS were true-positive findings, a replication study was performed herein through genotype-phenotype associations. The two tested SNPs were found to show significant associations with milk production traits, which confirmed the associations observed in the original study. Specifically, SNPs lying in the PTK2 gene were also detected by sequencing 14 unrelated sires in Chinese Holsteins and a total of thirty-three novel SNPs were identified. Thirteen out of these identified SNPs were genotyped and tested for association with milk production traits in an independent resource population. After Bonferroni correction for multiple testing, twelve SNPs were statistically significant for more than two milk production traits. Analyses of pairwise D' measures of linkage disequilibrium (LD) between all SNPs were also explored. Two haplotype blocks were inferred and the association study at haplotype level revealed similar effects on milk production traits. In addition, the RNA expression analyses revealed that a non-synonymous coding SNP (g.4061098T>G) was involved in the regulation of gene expression. Thus the findings presented here provide strong evidence for associations of PTK2 variants with dairy production traits and may be applied in Chinese Holstein breeding program.

  16. Wounding tomato fruit elicits ripening-stage specific changes in gene expression and production of volatile compounds.

    Science.gov (United States)

    Baldassarre, Valentina; Cabassi, Giovanni; Spadafora, Natasha D; Aprile, Alessio; Müller, Carsten T; Rogers, Hilary J; Ferrante, Antonio

    2015-03-01

    Fleshy fruits develop from an unripe organ that needs to be protected from damage to a ripe organ that attracts frugivores for seed dispersal through production of volatile organic compounds (VOCs). Thus, different responses to wounding damage are predicted. The aim of this study was to discover whether wound-induced changes in the transcriptome and VOC production alter as tomato transitions from unripe to ripe. Transcript changes were analysed 3h post-wounding using microarray analysis in two commercial salad-tomato (Solanum lycopersicum L.) cultivars: Luna Rossa and AVG, chosen for their high aroma production. This was followed by quantitative PCR on Luna Rossa genes involved in VOC biosynthesis and defence responses. VOCs elicited by wounding at different ripening stages were analysed by solid phase micro extraction and gas chromatography-mass spectrometry. Approximately 4000 differentially expressed genes were identified in the cultivar AVG and 2500 in Luna Rossa. In both cultivars the majority of genes were up-regulated and the most affected pathways were metabolism of terpenes, carotenoids, and lipids. Defence-related genes were mostly up-regulated in immature stages of development, whereas expression of genes related to VOCs changed at riper stages. More than 40 VOCs were detected and profiles changed with ripening stage. Thus, both transcriptome and VOC profiles elicited by wounding depend on stage of ripening, indicating a shift from defence to attraction.

  17. Study of gene expression and OTA production by Penicillium nordicum during a small-scale seasoning process of salami.

    Science.gov (United States)

    Ferrara, Massimo; Magistà, Donato; Epifani, Filomena; Cervellieri, Salvatore; Lippolis, Vincenzo; Gallo, Antonia; Perrone, Giancarlo; Susca, Antonia

    2016-06-16

    Penicillium nordicum, an important and consistent producer of ochratoxin A (OTA), is a widely distributed contaminant of protein rich food with elevated NaCl. It is usually found on dry-cured meat products and is considered the main species responsible for their contamination by OTA. The aim of this work was to study the gene expression of a polyketide synthase (otapksPN) involved in P. nordicum OTA biosynthesis, and OTA production during a small-scale seasoning process. Fresh pork sausages were surface inoculated with P. nordicum and seasoned for 30days. Gene expression and OTA production were monitored throughout the seasoning process after 4, 5, 6, 7, 10, 14, and 30days. The expression of otapksPN gene was already detected after 4days and increased significantly after 7days of seasoning, reaching the maximum expression level after 10days (1.69×10(4)copies/100mg). Consistently with gene expression monitoring, OTA was detected from the 4th day and its content increased significantly from the 7th day, reaching the maximum level after 10days. In the late stages of the seasoning process, OTA did not increase further and the number of gene copies was progressively reduced after 14 and 30days.

  18. Enterohaemolysin production and verotoxin genes in Esche-richia coli strains isolated from neonatal calves in India

    Institute of Scientific and Technical Information of China (English)

    Diganta Pan; Ashok Kumar Bhatia; KNBhilegaonkar

    2009-01-01

    Objective:To screened all haemolytic strains of Escherichia coli (E.coli)for the presence of verotoxin genes and speculate the association between enterohaemolysin production and presence of verotoxin genes.Methods:A total 176 of E.coli strains of 64 serogroups isolated from neonatal calves were selected and screened for al-pha-haemolysin and enterohaemolysin production on sheep blood agar and 5% washed sheep blood agar.Two types of haemolytic strains were further characterized by PCR for presence of Verotoxin gene (VT1 and VT2) and confirmed by verocell cytotoxicity assay.Results:Among 27 enterohaemolytic positive strains,19 (70. 37%)strains were found positive for presence of verotoxins (VTs)gene and verocell cytotoxicity assay. Whereas 34 alpha-haemolysin strains were found negative for VTs.Eight strains of E.coli were found VTs neg-ative but Ehx positive.Conclusion:The close association between enterohaemolysin production and presence of verotoxin genes makes it useful epidemiological marker for rapid screening of Verotoxic E.coli but this pheno-typic marker for screening of verotoxigenic Escherichia coli(VTEC)alone may raise a question in animal.

  19. Increased Production of Fatty Acids and Triglycerides in Aspergillus oryzae by Enhancing Expressions of Fatty Acid Synthesis-Related Genes

    Energy Technology Data Exchange (ETDEWEB)

    Tamano, Koichi; Bruno, Kenneth S.; Karagiosis, Sue A.; Culley, David E.; Deng, Shuang; Collett, James R.; Umemura, Myco; Koike, Hideaki; Baker, Scott E.; Machida, Masa

    2013-01-01

    Microbial production of fats and oils is being developedas a means of converting biomass to biofuels. Here we investigate enhancing expression of enzymes involved in the production of fatty acids and triglycerides as a means to increase production of these compounds in Aspergillusoryzae. Examination of the A.oryzaegenome demonstrates that it contains twofatty acid synthases and several other genes that are predicted to be part of this biosynthetic pathway. We enhancedthe expressionof fatty acid synthesis-related genes by replacing their promoters with thepromoter fromthe constitutively highly expressedgene tef1. We demonstrate that by simply increasing the expression of the fatty acid synthasegenes we successfullyincreasedtheproduction of fatty acids and triglyceridesby more than two fold. Enhancement of expression of the fatty acid pathway genes ATP-citrate lyase and palmitoyl-ACP thioesteraseincreasedproductivity to a lesser extent.Increasing expression ofacetyl-CoA carboxylase caused no detectable change in fatty acid levels. Increases in message level for each gene were monitored usingquantitative real-time RT-PCR. Our data demonstrates that a simple increase in the abundance of fatty acid synthase genes can increase the detectable amount of fatty acids.

  20. Improvement of L-valine production at high temperature in Brevibacterium flavum by overexpressing ilvEBNrC genes.

    Science.gov (United States)

    Hou, Xiaohu; Ge, Xiangyang; Wu, Di; Qian, He; Zhang, Weiguo

    2012-01-01

    Brevibacterium flavum ATCC14067 was engineered for L: -valine production by overexpression of different ilv genes; the ilvEBN(r)C genes from B. flavum NV128 provided the best candidate for L: -valine production. In traditional fermentation, L: -valine production reached 30.08 ± 0.92 g/L at 31°C in 72 h with a low conversion efficiency of 0.129 g/g. To further improve the L: -valine production and conversion efficiency based on the optimum temperatures of L: -valine biosynthesis enzymes (above 35°C) and the thermotolerance of B. flavum, the fermentation temperature was increased to 34, 37, and 40°C. As a result, higher metabolic rate and L: -valine biosynthesis enzymes activity were obtained at high temperature, and the maximum L: -valine production, conversion efficiency, and specific L: -valine production rate reached 38.08 ± 1.32 g/L, 0.241 g/g, and 0.133 g g(-1) h(-1), respectively, at 37°C in 48 h fermentation. The strategy for enhancing L: -valine production by overexpression of key enzymes in thermotolerant strains may provide an alternative approach to enhance branched-chain amino acids production with other strains.

  1. Variation in siderophore biosynthetic gene distribution and production across environmental and faecal populations of Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Laura J Searle

    Full Text Available Iron is essential for Escherichia coli growth and survival in the host and the external environment, but its availability is generally low due to the poor solubility of its ferric form in aqueous environments and the presence of iron-withholding proteins in the host. Most E. coli can increase access to iron by excreting siderophores such as enterobactin, which have a very strong affinity for Fe3+. A smaller proportion of isolates can generate up to 3 additional siderophores linked with pathogenesis; aerobactin, salmochelin, and yersiniabactin. However, non-pathogenic E. coli are also able to synthesise these virulence-associated siderophores. This raises questions about their role in the ecology of E. coli, beyond virulence, and whether specific siderophores might be linked with persistence in the external environment. Under the assumption that selection favours phenotypes that confer a fitness advantage, we compared siderophore production and gene distribution in E. coli isolated either from agricultural plants or the faeces of healthy mammals. This population-level comparison has revealed that under iron limiting growth conditions plant-associated isolates produced lower amounts of siderophores than faecal isolates. Additionally, multiplex PCR showed that environmental isolates were less likely to contain loci associated with aerobactin and yersiniabactin synthesis. Although aerobactin was linked with strong siderophore excretion, a significant difference in production was still observed between plant and faecal isolates when the analysis was restricted to strains only able to synthesise enterobactin. This finding suggests that the regulatory response to iron limitation may be an important trait associated with adaptation to the non-host environment. Our findings are consistent with the hypothesis that the ability to produce multiple siderophores facilitates E. coli gut colonisation and plays an important role in E. coli commensalism.

  2. Exploring the Transcriptome Landscape of Pomegranate Fruit Peel for Natural Product Biosynthetic Gene and SSR Marker Discovery(F).

    Science.gov (United States)

    Ono, Nadia Nicole; Britton, Monica Therese; Fass, Joseph Nathaniel; Nicolet, Charles Meyer; Lin, Dawei; Tian, Li

    2011-10-01

    Pomegranate fruit peel is rich in bioactive plant natural products, such as hydrolyzable tannins and anthocyanins. Despite their documented roles in human nutrition and fruit quality, genes involved in natural product biosynthesis have not been cloned from pomegranate and very little sequence information is available on pomegranate in the public domain. Shotgun transcriptome sequencing of pomegranate fruit peel cDNA was performed using RNA-Seq on the Illumina Genome Analyzer platform. Over 100 million raw sequence reads were obtained and assembled into 9,839 transcriptome assemblies (TAs) (>200 bp). Candidate genes for hydrolyzable tannin, anthocyanin, flavonoid, terpenoid and fatty acid biosynthesis and/or regulation were identified. Three lipid transfer proteins were obtained that may contribute to the previously reported IgE reactivity of pomegranate fruit extracts. In addition, 115 SSR markers were identified from the pomegranate fruit peel transcriptome and primers were designed for 77 SSR markers. The pomegranate fruit peel transcriptome set provides a valuable platform for natural product biosynthetic gene and SSR marker discovery in pomegranate. This work also demonstrates that next-generation transcriptome sequencing is an economical and effective approach for investigating natural product biosynthesis, identifying genes controlling important agronomic traits, and discovering molecular markers in non-model specialty crop species.

  3. Improved polysaccharide production in a submerged culture of Ganoderma lucidum by the heterologous expression of Vitreoscilla hemoglobin gene.

    Science.gov (United States)

    Li, Huan-Jun; Zhang, De-Huai; Yue, Tong-Hui; Jiang, Lu-Xi; Yu, Xuya; Zhao, Peng; Li, Tao; Xu, Jun-Wei

    2016-01-10

    Expression of Vitreoscilla hemoglobin (VHb) gene was used to improve polysaccharide production in Ganoderma lucidum. The VHb gene, vgb, under the control of the constitutive glyceraldehyde-3-phosphate dehydrogenase gene promoter was introduced into G. lucidum. The activity of expressed VHb was confirmed by the observation of VHb specific CO-difference spectrum with a maximal absorption at 419 nm for the transformant. The effects of VHb expression on intracellular polysaccharide (IPS) content, extracellular polysaccharide (EPS) production and transcription levels of three genes encoding the enzymes involved in polysaccharide biosynthesis, including phosphoglucomutase (PGM), uridine diphosphate glucose pyrophosphorylase (UGP), and β-1,3-glucan synthase (GLS), were investigated. The maximum IPS content and EPS production in the vgb-bearing G. lucidum were 26.4 mg/100mg dry weight and 0.83 g/L, respectively, which were higher by 30.5% and 88.2% than those of the wild-type strain. The transcription levels of PGM, UGP and GLS were up-regulated by 1.51-, 1.55- and 3.83-fold, respectively, in the vgb-bearing G. lucidum. This work highlights the potential of VHb to enhance G. lucidum polysaccharide production by large scale fermentation.

  4. High-level production of beta-carotene in Saccharomyces cerevisiae by successive transformation with carotenogenic genes from Xanthophyllomyces dendrorhous

    NARCIS (Netherlands)

    Verwaal, R.; Wang, J.; Meijnen, J.P.; Visser, H.; Sandmann, G.; Berg, van den J.A.; Ooyen, van A.J.J.

    2007-01-01

    To determine whether Saccharomyces cerevisiae can serve as a host for efficient carotenoid and especially ß-carotene production, carotenogenic genes from the carotenoid-producing yeast Xanthophyllomyces dendrorhous were introduced and overexpressed in S. cerevisiae. Because overexpression of these g

  5. Exploring the Transcriptome Landscape of Pomegranate Fruit Peel for Natural Product Biosynthetic Gene and SSR Marker Discovery

    Institute of Scientific and Technical Information of China (English)

    Nadia Nicole Ono; Monica Therese Britton; Joseph Nathaniel Fass; Charles Meyer Nicolet; Dawei Lin; Li Tian

    2011-01-01

    Pomegranate fruit peel is rich in bioactive plant natural products,such as hydrolyzable tannins and anthocyanins.Despite their documented roles in human nutrition and fruit quality,genes involved in natural product biosynthesis have not been cloned from pomegranate and very little sequence information is available on pomegranate in the public domain.Shotgun transcriptome sequencing of pomegranate fruit peel cDNA was performed using RNA-Seq on the Illumina Genome Analyzer platform.Over 100 million raw sequence reads were obtained and assembled into 9,839 transcriptome assemblies (TAs) (>200 bp).Candidate genes for hydrolyzable tannin,anthocyanin,flavonoid,terpenoid and fatty acid biosynthesis and/or regulation were identified.Three lipid transfer proteins were obtained that may contribute to the previously reported IgE reactivity of pomegranate fruit extracts.In addition,115 SSR markers were identified from the pomegranate fruit peel transcriptome and primers were designed for 77 SSR markers.The pomegranate fruit peel transcriptome set provides a valuable platform for natural product biosynthetic gene and SSR marker discovery in pomegranate.This work also demonstrates that next-generation transcriptome sequencing is an economical and effective approach for investigating natural product biosynthesis,identifying genes controlling important agronomic traits,and discovering molecular markers in non-model specialty crop species.

  6. Gene

    Data.gov (United States)

    U.S. Department of Health & Human Services — Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes,...

  7. Increased glycopeptide production after overexpression of shikimate pathway genes being part of the balhimycin biosynthetic gene cluster

    DEFF Research Database (Denmark)

    Thykær, Jette; Nielsen, Jens; Wohlleben, W.

    2010-01-01

    Amycolatopsis balhimycina produces the vancomycin-analogue balhimycin. The strain therefore serves as a model strain for glycopeptide antibiotic production. Previous characterisation of the balhimycin biosynthetic cluster had shown that the border sequences contained both, a putative 3-deoxy...

  8. The electron transfer flavoprotein fixABCX gene products from Azospirillum brasilense show a NifA-dependent promoter regulation.

    Science.gov (United States)

    Sperotto, Raul Antonio; Gross, Jeferson; Vedoy, Cleber; Passaglia, Luciane Maria Pereira; Schrank, Irene Silveira

    2004-10-01

    The complete nucleotide sequence of the A. brasilense fixA, fixB, fixC, and fixX genes is reported here. Sequence similarities between the protein sequences deduced from fixABCX genes and many electron transfer flavoproteins (ETFs) have been noted. Comparison of the amino acid sequences of both subunits of ETF with the A. brasilense fixA and fixB gene products exhibits an identity of 30%. The amino acid sequence of the other two genes, fixC and fixX, revealed similarity with the membrane-bound electron transfer flavoprotein ubiquinone oxidoreductase (ETF-QO). Using site-directed mutagenesis, mutations were introduced in the fixA promoter element of the A. brasilense fixABCX operon and chimeric p fixA-lacZ reporter gene fusions were constructed. The activation of the fixA promoter of A. brasilense is dependent upon the presence of the NifA protein being approximately 7 times less active than the A. brasilense nifH promoter. These results indicate that NifA from Klebsiella pneumoniae activates the fix promoter of A. brasilense and provide further evidence in support of the regulatory model of NifA activation in A. brasilense. Although no specific function has been assigned to the fixABCX gene products they are apparently required for symbiotic nitrogen fixation. An electron-transferring capacity in the nitrogen fixation pathway has been suggested for the fix gene products based on sequence homologies to the ETFs and ETF-QO proteins and by the absence of orthologous electron transfer proteins NifJ and NifF in A. brasilense.

  9. Evaluation of three herbicide resistance genes for use in genetic transformations and for potential crop protection in algae production.

    Science.gov (United States)

    Brueggeman, Andrew J; Kuehler, Daniel; Weeks, Donald P

    2014-09-01

    Genes conferring resistance to the herbicides glyphosate, oxyfluorfen and norflurazon were developed and tested for use as dominant selectable markers in genetic transformation of Chlamydomonas reinhardtii and as potential tools for the protection of commercial-scale algal production facilities against contamination by organisms sensitive to these broad-spectrum herbicides. A synthetic glyphosate acetyltransferase (GAT) gene, when fitted with a strong Chlamydomonas promoter, conferred a 2.7×-fold increase in tolerance to the EPSPS inhibitor, glyphosate, in transgenic cells compared with progenitor WT cells. A mutant Chlamydomonas protoporphyrinogen oxidase (protox, PPO) gene previously shown to produce an enzyme insensitive to PPO-inhibiting herbicides, when genetically engineered, generated transgenic cells able to tolerate up to 136× higher levels of the PPO inhibitor, oxyfluorfen, than nontransformed cells. Genetic modification of the Chlamydomonas phytoene desaturase (PDS) gene-based gene sequences found in various norflurazon-resistant organisms allowed production of transgenic cells tolerant to 40× higher levels of norflurazon than nontransgenic cells. The high efficiency of all three herbicide resistance genes in producing transgenic cells demonstrated their suitability as dominant selectable markers for genetic transformation of Chlamydomonas and, potentially, other eukaryotic algae. However, the requirement for high concentrations of glyphosate and its associated negative effects on cell growth rates preclude its consideration for use in large-scale production facilities. In contrast, only low doses of norflurazon and oxyfluorfen (~1.5 μm and ~0.1 μm, respectively) are required for inhibition of cell growth, suggesting that these two herbicides may prove effective in large-scale algal production facilities in suppressing growth of organisms sensitive to these herbicides.

  10. The loose evolutionary relationships between transcription factors and other gene products across prokaryotes.

    Science.gov (United States)

    del Grande, Marc; Moreno-Hagelsieb, Gabriel

    2014-12-17

    Tests for the evolutionary conservation of associations between genes coding for transcription factors (TFs) and other genes have been limited to a few model organisms due to the lack of experimental information of functional associations in other organisms. We aimed at surmounting this limitation by using the most co-occurring gene pairs as proxies for the most conserved functional interactions available for each gene in a genome. We then used genes predicted to code for TFs to compare their most conserved interactions against the most conserved interactions for the rest of the genes within each prokaryotic genome available. We plotted profiles of phylogenetic profiles, p-cubic, to compare the maximally scoring interactions of TFs against those of other genes. In most prokaryotes, genes coding for TFs showed lower co-occurrences when compared to other genes. We also show that genes coding for TFs tend to have lower Codon Adaptation Indexes compared to other genes. The co-occurrence tests suggest that transcriptional regulation evolves quickly in most, if not all, prokaryotes. The Codon Adaptation Index analyses suggest quick gene exchange and rewiring of transcriptional regulation across prokaryotes.

  11. Identification of genes implicated in toxin production in the cyanobacterium Cylindrospermopsis raciborskii

    DEFF Research Database (Denmark)

    Schembri, Mark; Neilan, B.A.; Saint, C.P.

    2001-01-01

    of the strain-specific distribution of the PKS and PS genes in C. raciborskii isolates demonstrated a direct link between the presence of these two genes and the ability to produce cylindrospermopsin. Interestingly, the possession of these two genes was also linked. They were also identified in an Anabaena...

  12. Some Production Characteristics of Kivircik, Gokceada and Sakiz Breeds of Sheep Conserved as Gene Resources

    Directory of Open Access Journals (Sweden)

    T. Sezenler

    2007-05-01

    Full Text Available This study was carried out to investigate the fertility, milk production and body weight of ewes and the survival rates and growth characteristics for Kıvırcık, Gokceada and Sakız breeds of sheep kept as gene resources in western part of Turkiye. Kıvırcık, Gokceada and Sakız breeds of sheep are included in the project for conservation of indigenious breeds as genetic resources.Lambing rate, litter size, milk yield and live weight for Kıvırcık, Gökçeada and Sakız ewes were 79.8 %, 67.6 % and 74.5 %; 1.26, 1.24 and 1.83; 41.8, 51.1 and 58.0 kg; 62.60, 51.39, and 48.52 kg. respectively. The lambs produced by Kıvırcık, Gokceada and Sakız ewes had 97 %, 94.7 % and 92.2 % survival rates to weaning; 4.09, 3.52 and 3.93 kg. birth weights; 38.17, 29.25 and 30.82 kg. weaning weights; 43.14, 35.57 and 34.64 kg. sixth month weights; 49.13, 39.70 and 37.39 kg. yearling weights respectively.

  13. Association of genetic polymorphism in GH gene with milk production traits in Beijing Holstein cows

    Indian Academy of Sciences (India)

    Guo Li Zhou; Hai Guo Jin; Chen Liu; Shan Li; Qi Zhu; Yu Hou Wu

    2005-12-01

    Associations were analysed between polymorphisms of the growth hormone gene (GH-MspI) (localized in intron 3) and milk production traits of Beijing Holstein cows (a total of 543 cows). Polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method was used for identification of various genotypes. Frequencies of genotypes were 0.77, 0.21 and 0.02 for A/A, A/B and B/B, respectively. The frequency of the allele is 0.875. The results of the least squares means show that in all three lactations, the GH A/A cows yielded more milk ( < 0.01 for lactation I and < 0.05 for lactations II and III), whereas A/B cows showed higher milk fat content than A/A individuals ( < 0.05 for lactations I and II, and < 0.01 for lactation III). The A/A cows yielded more fat than A/B individuals ( < 0.01 only in lactation I). The A/A cows yielded more milk protein than A/B individuals ( < 0.01 for lactations I, II, and III). The A/A cows produced milk of higher protein content than of A/B individuals ( < 0.05 only in lactation II).

  14. Differential sorting and packaging of capa-gene related products in an insect.

    Science.gov (United States)

    Pollák, Edit; Eckert, Manfred; Molnár, László; Predel, Reinhard

    2005-01-03

    A unique costorage of neuropeptides was recently found in the abdominal perisympathetic organs (PSOs) of the American cockroach, Periplaneta americana. Having specific antisera directed against all peptides belonging to this neurosecretory system, we examined the sorting of PSO-peptides in the soma of the median neurosecretory cells of abdominal ganglia by using immunoelectron microscopic double stainings. The data indicate that all six abundant neuropeptides of this neurohormonal system, which includes three capa-gene related products, are primarily incorporated into separate vesicles. These vesicles fuse with each other in the cytoplasm and become translucent on their way to the axon hillock. By means of light microscopy and MALDI-TOF mass spectrometry, an identical population of neuropeptides was found in interneurons of the brain. As revealed by subsequent immunoelectron microscopic analysis, the peptides of these cells are separately packed into dense core vesicles but do not fuse with each other. Thus, hitherto unknown cell-type-specific sorting mechanisms occur in neurosecretory cells and interneurons, respectively.

  15. Production of marker-free disease-resistant potato using isopentenyl transferase gene as a positive selection marker.

    Science.gov (United States)

    Khan, Raham Sher; Ntui, Valentine Otang; Chin, Dong Poh; Nakamura, Ikuo; Mii, Masahiro

    2011-04-01

    The use of antibiotic or herbicide resistant genes as selection markers for production of transgenic plants and their continuous presence in the final transgenics has been a serious problem for their public acceptance and commercialization. MAT (multi-auto-transformation) vector system has been one of the different strategies to excise the selection marker gene and produce marker-free transgenic plants. In the present study, ipt (isopentenyl transferase) gene was used as a selection marker gene. A chitinase gene, ChiC (isolated from Streptomyces griseus strain HUT 6037) was used as a gene of interest. ChiC gene was cloned from the binary vector, pEKH1 to an ipt-type MAT vector, pMAT21 by gateway cloning and transferred to Agrobacterium tumefaciens strain EHA105. The infected tuber discs of potato were cultured on hormone- and antibiotic-free MS medium. Seven of the 35 explants infected with the pMAT21/ChiC produced shoots. The same antibiotic- and hormones-free MS medium was used in subcultures of the shoots (ipt like and normal shoots). Molecular analyses of genomic DNA from transgenic plants confirmed the integration of gene of interest and excision of the selection marker in 3 of the 7 clones. Expression of ChiC gene was confirmed by Northern blot and western blot analyses. Disease-resistant assay of the marker-free transgenic, in vitro and greenhouse-grown plants exhibited enhanced resistance against Alternaria solani (early blight), Botrytis cinerea (gray mold) and Fusarium oxysporum (Fusarium wilt). From these results it could be concluded that ipt gene can be used as a selection marker to produce marker-free disease-resistant transgenic potato plants on PGR- and antibiotic-free MS medium.

  16. Deletion of genes involved in glutamate metabolism to improve poly-gamma-glutamic acid production in B. amyloliquefaciens LL3.

    Science.gov (United States)

    Zhang, Wei; He, Yulian; Gao, Weixia; Feng, Jun; Cao, Mingfeng; Yang, Chao; Song, Cunjiang; Wang, Shufang

    2015-02-01

    Here, we attempted to elevate poly-gamma-glutamic acid (γ-PGA) production by modifying genes involved in glutamate metabolism in Bacillus amyloliquefaciens LL3. Products of rocR, rocG and gudB facilitate the conversion from glutamate to 2-oxoglutarate in Bacillus subtillis. The gene odhA is responsible for the synthesis of a component of the 2-oxoglutarate dehydrogenase complex that catalyzes the oxidative decarboxylation of 2-oxoglutarate to succinyl coenzyme A. In-frame deletions of these four genes were performed. In shake flask experiments the gudB/rocG double mutant presented enhanced production of γ-PGA, a 38 % increase compared with wild type. When fermented in a 5-L fermenter with pH control, the γ-PGA yield of the rocR mutant was increased to 5.83 g/L from 4.55 g/L for shake flask experiments. The gudB/rocG double mutant produced 5.68 g/L γ-PGA compared with that of 4.03 g/L for the wild type, a 40 % increase. Those results indicated the possibility of improving γ-PGA production by modifying glutamate metabolism, and identified potential genetic targets to improve γ-PGA production.

  17. Linking gene regulation and the exo-metabolome: A comparative transcriptomics approach to identify genes that impact on the production of volatile aroma compounds in yeast

    Directory of Open Access Journals (Sweden)

    Bauer Florian F

    2008-11-01

    Full Text Available Abstract Background 'Omics' tools provide novel opportunities for system-wide analysis of complex cellular functions. Secondary metabolism is an example of a complex network of biochemical pathways, which, although well mapped from a biochemical point of view, is not well understood with regards to its physiological roles and genetic and biochemical regulation. Many of the metabolites produced by this network such as higher alcohols and esters are significant aroma impact compounds in fermentation products, and different yeast strains are known to produce highly divergent aroma profiles. Here, we investigated whether we can predict the impact of specific genes of known or unknown function on this metabolic network by combining whole transcriptome and partial exo-metabolome analysis. Results For this purpose, the gene expression levels of five different industrial wine yeast strains that produce divergent aroma profiles were established at three different time points of alcoholic fermentation in synthetic wine must. A matrix of gene expression data was generated and integrated with the concentrations of volatile aroma compounds measured at the same time points. This relatively unbiased approach to the study of volatile aroma compounds enabled us to identify candidate genes for aroma profile modification. Five of these genes, namely YMR210W, BAT1, AAD10, AAD14 and ACS1 were selected for overexpression in commercial wine yeast, VIN13. Analysis of the data show a statistically significant correlation between the changes in the exo-metabome of the overexpressing strains and the changes that were predicted based on the unbiased alignment of transcriptomic and exo-metabolomic data. Conclusion The data suggest that a comparative transcriptomics and metabolomics approach can be used to identify the metabolic impacts of the expression of individual genes in complex systems, and the amenability of transcriptomic data to direct applications of

  18. Coagulase gene polymorphism of Staphylococcus aureus isolates: A study on dairy food products and other foods in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Soltan Dallal

    2016-12-01

    Full Text Available Coagulase is considered as a major determinant factor for the identification of Staphylococcus aureus strains. The 3′-end coding region of the coagulase (coa gene contains a series of 81-bp tandem repeats, which differ in the number and location of enzymatic restriction sites among different isolates. coa PCR-RFLP has been used widely to type S. aureus isolates in epidemiological studies. The current study was conducted to investigate the coagulase gene polymorphisms in S. aureus isolated from various food samples using an in house PCR-RFLP method. A total of 100 strains of S. aureus were isolated from food samples. Isolates were typed by PCR-RFLP analysis using NdeI restriction digestion of the coagulase gene PCR products. Results showed that amplification of coagulase genes from S. aureus produced different PCR products. The isolates were grouped into 18 genotypes using RFLP analysis results of the genes. In this study, the S. aureus isolates have been shown to include more than one coagulase genotype, but only had a few coa genotypes predominated.

  19. Production, characterization and gene cloning of the extracellular enzymes from the marine-derived yeasts and their potential applications.

    Science.gov (United States)

    Chi, Zhenming; Chi, Zhe; Zhang, Tong; Liu, Guanglei; Li, Jing; Wang, Xianghong

    2009-01-01

    In this review article, the extracellular enzymes production, their properties and cloning of the genes encoding the enzymes from marine yeasts are overviewed. Several yeast strains which could produce different kinds of extracellular enzymes were selected from the culture collection of marine yeasts available in this laboratory. The strains selected belong to different genera such as Yarrowia, Aureobasidium, Pichia, Metschnikowia and Cryptococcus. The extracellular enzymes include cellulase, alkaline protease, aspartic protease, amylase, inulinase, lipase and phytase, as well as killer toxin. The conditions and media for the enzyme production by the marine yeasts have been optimized and the enzymes have been purified and characterized. Some genes encoding the extracellular enzymes from the marine yeast strains have been cloned, sequenced and expressed. It was found that some properties of the enzymes from the marine yeasts are unique compared to those of the homologous enzymes from terrestrial yeasts and the genes encoding the enzymes in marine yeasts are different from those in terrestrial yeasts. Therefore, it is of very importance to further study the enzymes and their genes from the marine yeasts. This is the first review on the extracellular enzymes and their genes from the marine yeasts.

  20. Enhanced production of 24S-hydroxycholesterol is not sufficient to drive liver X receptor target genes in vivo.

    Science.gov (United States)

    Shafaati, M; Olin, M; Båvner, A; Pettersson, H; Rozell, B; Meaney, S; Parini, P; Björkhem, I

    2011-10-01

    Oxysterols such as 24S-hydroxycholesterol (OHC) and 27-OHC are intermediates of cholesterol excretion pathways. In addition, they are putative endogenous agonists of the liver X receptor (LXR) class of nuclear hormone receptors and are thought to be important mediators of cholesterol-dependent gene regulation. 24S-OHC is one of the most efficient endogenous LXR agonists known and is present in the brain and in the circulation at relatively high levels. To explore the regulatory importance of 24S-OHC in vivo. We developed a transgenic mouse model in which human cholesterol 24-hydroxylase, the enzyme responsible for the formation of 24S-OHC, was expressed under the control of a promoter derived from the β-actin gene. Both male and female transgenic mice had elevated levels of cerebral, plasma, biliary and faecal 24S-OHC. According to the faecal excretion results, production of 24S-OHC was increased four- to sevenfold. Gene expression profiling revealed that the elevated production of 24S-OHC did not result in the anticipated activation of LXR target genes in the brain or liver. In spite of the fact that 24S-OHC is a highly effective agonist of LXRs in vitro, it is not a critical activator of target genes to this nuclear receptor in vivo, either in the brain or in the liver. © 2011 The Association for the Publication of the Journal of Internal Medicine.

  1. Use of Staby(®) technology for development and production of DNA vaccines free of antibiotic resistance gene.

    Science.gov (United States)

    Reschner, Anca; Scohy, Sophie; Vandermeulen, Gaëlle; Daukandt, Marc; Jacques, Céline; Michel, Benjamin; Nauwynck, Hans; Xhonneux, Florence; Préat, Véronique; Vanderplasschen, Alain; Szpirer, Cédric

    2013-10-01

    The appearance of new viruses and the cost of developing certain vaccines require that new vaccination strategies now have to be developed. DNA vaccination seems to be a particularly promising method. For this application, plasmid DNA is injected into the subject (man or animal). This plasmid DNA encodes an antigen that will be expressed by the cells of the subject. In addition to the antigen, the plasmid also encodes a resistance to an antibiotic, which is used during the construction and production steps of the plasmid. However, regulatory agencies (FDA, USDA and EMA) recommend to avoid the use of antibiotics resistance genes. Delphi Genetics developed the Staby(®) technology to replace the antibiotic-resistance gene by a selection system that relies on two bacterial genes. These genes are small in size (approximately 200 to 300 bases each) and consequently encode two small proteins. They are naturally present in the genomes of bacteria and on plasmids. The technology is already used successfully for production of recombinant proteins to achieve higher yields and without the need of antibiotics. In the field of DNA vaccines, we have now the first data validating the innocuousness of this Staby(®) technology for eukaryotic cells and the feasibility of an industrial production of an antibiotic-free DNA vaccine. Moreover, as a proof of concept, mice have been successfully vaccinated with our antibiotic-free DNA vaccine against a deadly disease, pseudorabies (induced by Suid herpesvirus-1).

  2. Effects of excretory/secretory products from Anisakis simplex (Nematoda) on immune gene expression in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Bahlool, Qusay Z M; Skovgaard, Alf; Kania, Per W; Buchmann, Kurt

    2013-09-01

    Excretory/secretory (ES) products are molecules produced by parasitic nematodes, including larval Anisakis simplex, a parasite occurring in numerous marine fish hosts. The effects of these substances on host physiology have not been fully described. The present work elucidates the influence of ES substances on the fish immune system by measuring immune gene expression in spleen and liver of rainbow trout (Oncorhynchus mykiss) injected intraperitoneally with ES products isolated from A. simplex third stage larvae. The overall gene expression profile of exposed fish showed a generalized down-regulation of the immune genes tested, suggesting a role of ES proteins in immunomodulation. We also tested the enzymatic activity of the ES proteins and found that lipase, esterase/lipase, valine and cysteine arylamidases, naphthol-AS-BI-phosphohydrolase and α-galactosidase activities were present in the ES solution. This type of hydrolytic enzyme activity may play a role in nematode penetration of host tissue. In addition, based on the notion that A. simplex ES products may have an immune-depressive effect (by minimizing immune gene expression) it could also be suggested that worm enzymes directly target host immune molecules which would add to a decreased host immune response and increased worm survival.

  3. Effect of culture density and antioxidants on naupliar production and gene expression of the cyclopoid copepod, Paracyclopina nana.

    Science.gov (United States)

    Lee, Kyun-Woo; Rhee, Jae-Sung; Han, Jeonghoon; Park, Heum Gi; Lee, Jae-Seong

    2012-02-01

    Although attempts have been made to use mass cultures of marine copepods as live foods in marine aquaculture, some limitations such as low density culture still exist. The brackish water cyclopoid copepod, Paracyclopina nana has the potential for mass culturing as live food. In this study, we not only investigated the effect of culture density on the naupliar production and specific gene expressions of P. nana, but also the effect of several antioxidants under the conditions of a high density culture. The naupliar production of the copepod decreased with increasing culture density. The expression of glutathione reductase (GR), selenium-dependent glutathione peroxidase (SeGPx), glutathione S-transferase kappa (GST kappa), heat shock protein 40 (Hsp40), and Hsp70 genes of P. nana increased in the high density treatment but vitellogenin genes (Vg1 and Vg2) showed downregulation. In the condition with 20 inds./mL, vitamin C had a significant decrease but sodium selenite induced the naupliar production of P. nana greatly. The expressions of GR, SeGPx, Hsp70, and Vg genes increased with the vitamin C treatment. Sodium selenite caused a decrease of SeGPx and Hsp40 but GST kappa increased in the treatment with 20 inds./mL. These results suggest that sodium selenite is a positive antioxidant which can increase the culture efficiency of the copepod.

  4. Comparative Genomic Analysis of Delftia tsuruhatensis MTQ3 and the Identification of Functional NRPS Genes for Siderophore Production

    Directory of Open Access Journals (Sweden)

    Haimeng Guo

    2016-01-01

    Full Text Available Plant growth-promoting rhizobacteria (PGPR are a group of rhizosphere bacteria that promote plant growth. Delftia tsuruhatensis MTQ3 is a member of PGPR that produces siderophores. The draft genome sequence of MTQ3 has been reported. Here, we analyzed the genome sequence of MTQ3 and performed a comparative genome analysis of four sequenced Delftia strains, revealing genetic relationships among these strains. In addition, genes responsible for bacteriocin and nonribosomal peptide synthesis were detected in the genomes of each strain. To reveal the functions of NRPS genes in siderophore production in D. tsuruhatensis MTQ3, three NRPS genes were knocked out to obtain the three mutants MTQ3-Δ1941, MTQ3-Δ1945, and MTQ3-Δ1946, which were compared with the wild-type strain. In qualitative and quantitative analyses using CAS assay, the mutants failed to produce siderophores. Accordingly, the NRPS genes in MTQ3 were functionally related to siderophore production. These results clarify one mechanism by which plant growth is promoted in MTQ3 and have important applications in agricultural production.

  5. Overexpression of the laeA gene leads to increased production of cyclopiazonic acid in Aspergillus fumisynnematus.

    Science.gov (United States)

    Hong, Eun Jin; Kim, Na Kyeong; Lee, Doyup; Kim, Won Gon; Lee, Inhyung

    2015-11-01

    To explore novel bioactive compounds produced via activation of secondary metabolite (SM) gene clusters, we overexpressed an ortholog of laeA, a gene that encodes a global positive regulator of secondary metabolism in Aspergillus fumisynnematus F746. Overexpression of the laeA gene under the alcA promoter resulted in the production of less pigment, shorter conidial head chains, and fewer conidia. Thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) analysis revealed that SM production in OE::laeA was significantly increased, and included new metabolites that were not detected in the wild type. Among them, a compound named F1 was selected on the basis of its high production levels and antibacterial effects. F1 was purified by column chromatography and preparative TLC and identified as cyclopiazonic acid (CPA) by LC/MS, which had been previously known as mycotoxin. As A. fumisynnematus was not known to produce CPA, these results suggest that overexpression of the laeA gene can be used to explore the synthesis of useful bioactive compounds, even in a fungus for which the genome sequence is unavailable.

  6. SxtA and sxtG Gene Expression and Toxin Production in the Mediterranean Alexandrium minutum (Dinophyceae

    Directory of Open Access Journals (Sweden)

    Federico Perini

    2014-10-01

    Full Text Available The dinoflagellate Alexandrium minutum is known for the production of potent neurotoxins affecting the health of human seafood consumers via paralytic shellfish poisoning (PSP. The aim of this study was to investigate the relationship between the toxin content and the expression level of the genes involved in paralytic shellfish toxin (PST production. The algal cultures were grown both in standard f/2 medium and in phosphorus/nitrogen limitation. In our study, LC-HRMS analyses of PST profile and content in different Mediterranean A. minutum strains confirmed that this species was able to synthesize mainly the saxitoxin analogues Gonyautoxin-1 (GTX1 and Gonyautoxin-4 (GTX4. The average cellular toxin content varied among different strains, and between growth phases, highlighting a decreasing trend from exponential to stationary phase in all culture conditions tested. The absolute quantities of intracellular sxtA1 and sxtG mRNA were not correlated with the amount of intracellular toxins in the analysed A. minutum suggesting that the production of toxins may be regulated by post-transcriptional mechanisms and/or by the concerted actions of alternative genes belonging to the PST biosynthesis gene cluster. Therefore, it is likely that the sxtA1 and sxtG gene expression could not reflect the PST accumulation in the Mediterranean A. minutum populations under the examined standard and nutrient limiting conditions.

  7. Exploring the role of sigma factor gene expression on production by Corynebacterium glutamicum: sigma factor H and FMN as example.

    Science.gov (United States)

    Taniguchi, Hironori; Wendisch, Volker F

    2015-01-01

    Bacteria are known to cope with environmental changes by using alternative sigma factors binding to RNA polymerase core enzyme. Sigma factor is one of the targets to modify transcription regulation in bacteria and to influence production capacities. In this study, the effect of overexpressing each annotated sigma factor gene in Corynebacterium glutamicum WT was assayed using an IPTG inducible plasmid system and different IPTG concentrations. It was revealed that growth was severely decreased when sigD or sigH were overexpressed with IPTG concentrations higher than 50 μM. Overexpression of sigH led to an obvious phenotypic change, a yellow-colored supernatant. High performance liquid chromatography analysis revealed that riboflavin was excreted to the medium when sigH was overexpressed and DNA microarray analysis confirmed increased expression of riboflavin biosynthesis genes. In addition, genes for enzymes related to the pentose phosphate pathway and for enzymes dependent on flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD), or NADPH as cofactor were upregulated when sigH was overexpressed. To test if sigH overexpression can be exploited for production of riboflavin-derived FMN or FAD, the endogenous gene for bifunctional riboflavin kinase/FMN adenyltransferase was co-expressed with sigH from a plasmid. Balanced expression of sigH and ribF improved accumulation of riboflavin (19.8 ± 0.3 μM) and allowed for its conversion to FMN (33.1 ± 1.8 μM) in the supernatant. While a proof-of-concept was reached, conversion was not complete and titers were not high. This study revealed that inducible and gradable overexpression of sigma factor genes is an interesting approach to switch gene expression profiles and to discover untapped potential of bacteria for chemical production.

  8. Exploring the role of sigma factor gene expression on production by Corynebacterium glutamicum: sigma factor H and FMN as example

    Directory of Open Access Journals (Sweden)

    Hironori eTaniguchi

    2015-07-01

    Full Text Available Bacteria are known to cope with environmental changes by using alternative sigma factors binding to RNA polymerase core enzyme. Sigma factor is one of the targets to modify transcription regulation in bacteria and to influence production capacities. In this study, the effect of overexpressing each annotated sigma factor gene in C. glutamicum WT was assayed using an IPTG inducible plasmid system and different IPTG concentrations. It was revealed that growth was severely decreased when sigD or sigH were overexpressed with IPTG concentrations higher than 50 μM. Overexpression of sigH led to an obvious phenotypic change, a yellow-colored supernatant. HPLC analysis revealed that riboflavin was excreted to the medium when sigH was overexpressed and DNA microarray analysis confirmed increased expression of riboflavin biosynthesis genes. In addition, genes for enzymes related to the pentose phosphate pathway and for enzymes dependent on FMN, FAD or NADPH as cofactor were upregulated when sigH was overexpressed. To test if sigH overexpression can be exploited for production of riboflavin-derived FMN or FAD, the endogenous gene for bifunctional riboflavin kinase/FMN adenyltransferase was co-expressed with sigH from a plasmid. Balanced expression of sigH and ribF improved accumulation of riboflavin (19.8 ± 0.3 μM and allowed for its conversion to FMN (33.1 ± 1.8 μM in the supernatant. While a proof-of-concept was reached, conversion was not complete and titers were not high. This study revealed that inducible and gradable overexpression of sigma factor genes is an interesting approach to switch gene expression profiles and to discover untapped potential of bacteria for chemical production.

  9. Association ofVIPR-1gene polymorphisms and haplotypes with egg production in laying quails

    Institute of Scientific and Technical Information of China (English)

    Yue-jin PU; Yan WU; Xiao-juan XU; Jin-ping DU; Yan-zhang GONG

    2016-01-01

    The laying quail is a worldwide breed which exhibits high economic value. In our current study, the vas-oactive intestinal peptide receptor-1 (VIPR-1) was selected as the candidate gene for identifying traits of egg produc-tion. A single nucleotide polymorphism (SNP) detection was performed in 443 individual quails, including 196 quails from the H line, 202 quails from the L line, and 45 wild quails. The SNPs were genotyped using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Two mutations (G373T, A313G) were detected in al the tested quail populations. The associated analysis showed that the SNP genotypes of theVIPR-1 gene were sig-nificantly linked with the egg weight of G373T and A313G in 398 quails. The quails with the genotype GG always exhibited the largest egg weight for the two mutations in the H and L lines. Linkage disequilibrium (LD) analysis in-dicated that G373T and A313G loci showed the weakest LD. Seven main diplotypes from the four main reconstructed haplotypes were observed, indicating a significant association of diplotypes with egg weight. Quails with the h1h2 (GGGT) diplotype always exhibited the smalest egg weight and largest egg number at 20 weeks of age. The overall results suggest that the alterations in quails may be linked with potential major loci or genes affecting reproductive traits.%题目:VIPR-1基因多态性及其单倍型与蛋用鹌鹑产蛋性能的相关性研究目的:蛋用鹌鹑 VIPR-1基因单核苷酸多态性(SNP)研究。创新点:首次开展蛋用鹌鹑 VIPR-1基因多态性研究,发现了两个与蛋重相关的多态性位点。方法:以VIPR-1基因设计引物,进行聚合酶链式反应–限制片段长度多态性分析,获得基因突变位点。并通过关联性分析,研究基因多态性与繁殖性状之间的相关性。结论:在个体数为443个(202只L个体、196只H个体和45只野生鹌鹑个体)的群体中

  10. Association of gene BoLA DRB3.2 with production traits in a dairy herd of Antioquia, Colombia

    OpenAIRE

    Juan Zambrano A.; Julián Echeverri Z.; Albeiro López-Herrera

    2014-01-01

    ABSTRACTObjective. To determine the associations of BoLA DRB3.2 alleles present in Holstein and BON x Holstein cattle to production and milk quality traits in a dairy herd of Antioquia, Colombia. Materials and methods. Ninety-one cows, 66 Holstein and 25 BxH, were genotyped for the BoLA DRB3.2 gene, through PCR-RFLP technique. Furthermore, the association of the alleles of the gene BoLA DRB3.2 with milk yield (PL305), fat yield (PG305), protein yield (PP305) fat percentage (PGRA) and protein ...

  11. Association of gene BoLA DRB3.2 with production traits in a dairy herd of Antioquia, Colombia

    OpenAIRE

    Juan Zambrano A; Julián Echeverri Z.; Albeiro López-Herrera

    2014-01-01

    ABSTRACTObjective. To determine the associations of BoLA DRB3.2 alleles present in Holstein and BON x Holstein cattle to production and milk quality traits in a dairy herd of Antioquia, Colombia. Materials and methods. Ninety-one cows, 66 Holstein and 25 BxH, were genotyped for the BoLA DRB3.2 gene, through PCR-RFLP technique. Furthermore, the association of the alleles of the gene BoLA DRB3.2 with milk yield (PL305), fat yield (PG305), protein yield (PP305) fat percentage (PGRA) and protein ...

  12. Distribution of Salmonella paratyphi A outer membrane protein X gene and immune-protective effect related to its recombinant expressed products

    Institute of Scientific and Technical Information of China (English)

    李明雷

    2014-01-01

    Objective To determine the distribution and sequence conservation of outer membrane protein X(ompX)gene in Salmonella paratyphi A isolates as well as the immunogenicity and immono-protection of ompX gene products.Methods OmpX gene in Salmonella paratyphi A isolates was detected by PCR and the amplification products were sequenced after the T-A cloning process.OmpX gene product was expressed with E.coli expression system and the expressed rOmpX was extracted by Ni-NTA affinity

  13. Evidence for Horizontal Gene Transfer as Origin of Putrescine Production in Oenococcus oeni RM83▿

    Science.gov (United States)

    Marcobal, Ángela; de las Rivas, Blanca; Moreno-Arribas, M. Victoria; Muñoz, Rosario

    2006-01-01

    The nucleotide sequence of a 17.2-kb chromosomal DNA fragment containing the odc gene encoding ornithine decarboxylase has been determined in the putrescine producer Oenococcus oeni RM83. This DNA fragment contains 13 open reading frames, including genes coding for five transposases and two phage proteins. This description might represent the first evidence of a horizontal gene transfer event as the origin of a biogenic amine biosynthetic locus. PMID:17056681

  14. Evolution and Origin of HRS, a Protein Interacting with Merlin, the Neurofibromatosis 2 Gene Product

    Directory of Open Access Journals (Sweden)

    Leonid V. Omelyanchuk

    2009-10-01

    Full Text Available Hepatocyte growth factor receptor tyrosine kinase substrate (HRS is an endosomal protein required for trafficking receptor tyrosine kinases from the early endosome to the lysosome. HRS interacts with Merlin, the Neurofibromatosis 2 (NF2 gene product, and this interaction may be important for Merlin’s tumor suppressor activity. Understanding the evolution, origin, and structure of HRS may provide new insight into Merlin function. We show that HRS homologs are present across a wide range of Metazoa with the yeast Vps27 protein as their most distant ancestor. The phylogenetic tree of the HRS family coincides with species evolution and divergence, suggesting a unique function for HRS. Sequence alignment shows that various protein domains of HRS, including the VHS domain, the FYVE domain, the UIM domain, and the clathrin-binding domain, are conserved from yeast to multicellular organisms. The evolutionary transition from unicellular to multicellular organisms was accompanied by the appearance of a binding site for Merlin, which emerges in the early Metazoa after its separation from flatworms. In addition to the region responsible for growth suppression, the Merlin-binding and STAM-binding domains of HRS are conserved among multicellular organisms. The residue equivalent to tyrosine-377, which is phosphorylated in the human HRS protein, is highly conserved throughout the HRS family. Three additional conserved boxes lacking assigned functions are found in the HRS proteins of Metazoa. While boxes 1 and 3 may constitute the Eps-15- and Snx1-binding sites, respectively, box 2, containing the residue equivalent to tyrosine-377, is likely to be important for HRS phosphorylation. While several functional domains are conserved throughout the HRS family, the STAM-binding, Merlin-binding, and growth suppression domains evolved in the early Metazoa around the time the Merlin protein emerged. As these domains appear during the transition to multicellularity

  15. Neuronal and glial expression of the multidrug resistance gene product in an experimental epilepsy model.

    Science.gov (United States)

    Lazarowski, Alberto; Ramos, Alberto Javier; García-Rivello, Hernán; Brusco, Alicia; Girardi, Elena

    2004-02-01

    1. Failure of anticonvulsive drugs to prevent seizures is a common complication of epilepsy treatment known as drug-refractory epilepsy but their causes are not well understood. It is hypothesized that the multidrug resistance P-glycoprotein (Pgp-170), the product of the MDR-1 gene that is normally expressed in several excretory tissues including the blood brain barrier, may be participating in the refractory epilepsy. 2. Using two monoclonal antibodies against Pgp-170, we investigated the expression and cellular distribution of this protein in the rat brain during experimentally induced epilepsy. Repeated seizures were induced in male Wistar rats by daily administration of 3-mercaptopropionic acid (MP) 45 mg/kg i.p. for either 4 days (MP-4) or 7 days (MP-7). Control rats received an equivalent volume of vehicle. One day after the last injection, rats were sacrificed and brains were processed for immunohistochemistry for Pgp-170. As it was previously described, Pgp-170 immunostaining was observed in some brain capillary endothelial cells of animals from control group. 3. Increased Pgp-170 immunoreactivity was detected in MP-treated animals. Besides the Pgp-170 expressed in blood vessels, neuronal, and glial immunostaining was detected in hippocampus, striatum, and cerebral cortex of MP-treated rats. Pgp-170 immunolabeled neurons and glial cells were observed in a nonhomogeneous distribution. MP-4 animals presented a very prominent Pgp-170 immunostaining in the capillary endothelium, surrounding astrocytes and some neighboring neurons while MP-7 group showed increased neuronal labeling. 4. Our results demonstrate a selective increase in Pgp-170 immunoreactivity in the brain capillary endothelial cells, astrocytes, and neurons during repetitive MP-induced seizures. 5. The role for this Pgp-170 overexpression in endothelium and astrocytes as a clearance mechanism in the refractory epilepsy, and the consequences of neuronal Pgp-170 expression remain to be disclosed.

  16. Mechanism for the desulfurization of L-cysteine catalyzed by the nifS gene product.

    Science.gov (United States)

    Zheng, L; White, R H; Cash, V L; Dean, D R

    1994-04-19

    The nifS gene product (NIFS) is a pyridoxal phosphate binding enzyme that catalyzes the desulfurization of L-cysteine to yield L-alanine and sulfur. In Azotobacter vinelandii this activity is required for the full activation of the nitrogenase component proteins. Because the nitrogenase component proteins, Fe protein and MoFe protein, both contain metalloclusters which are required for their respective activities, it is suggested that NIFS participates in the biosynthesis of the nitrogenase metalloclusters by providing the inorganic sulfur required for Fe-S core formation [Zheng, L., White, R. H., Cash, V. L. Jack, R. F., & Dean, D. R. (1993) Proc. Natl. Acad. Sci. U.S.A. 90, 2754-2758]. In the present study the mechanism for the desulfurization of L-cysteine catalyzed by NIFS was determined in the following ways. First, the substrate analogs, L-allylglycine and vinylglycine, were shown to irreversibly inactivate NIFS by formation of a gamma-methylcystathionyl or cystathionyl residue, respectively, through nucleophilic attack by an active site cysteinyl residue on the corresponding analog-pyridoxal phosphate adduct. Second, this reactive cysteinyl residue, which is required for L-cysteine desulfurization activity, was identified as Cys325 by the specific alkylation of that residue and by site-directed mutagenesis experiments. Third, the formation of an enzyme-bound cysteinyl persulfide was identified as an intermediate in the NIFS-catalyzed reaction. Fourth, evidence was obtained for an enamine intermediate in the formation of L-alanine.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Detection of classical enterotoxins and identification of enterotoxin genes in Staphylococcus aureus from milk and dairy products.

    Science.gov (United States)

    Morandi, S; Brasca, M; Lodi, R; Cremonesi, P; Castiglioni, B

    2007-09-20

    Milk and dairy products are frequently contaminated with enterotoxigenic Staphylococcus aureus, which is often involved in staphylococcal food poisoning. The distribution of genes encoding staphylococcal enterotoxins (SE) in S. aureus isolated from bovine, goat, sheep and buffalo milk and dairy products was verified by the presence of the corresponding SE production. A total of 112 strains of S. aureus were tested for SE production by immuno-enzymatic (SEA-SEE) and reversed passive latex agglutination (SEA-SED) methods, while multiplex-PCR was applied for SE genes (sea, sec, sed, seg, seh, sei, sej and sel). Of the total strains studied, 67% were detected to have some SE genes (se), but only 52% produced a detectable amount of the classic antigenic SE types. The bovine isolates frequently had enterotoxin SEA, SED and sej, while SEC and sel predominated in the goat and sheep strains. The results demonstrated (i) marked enterotoxigenic S. aureus strain variations, in accordance with strain origin and (ii) the two methods resulted in different information but concurred on the risk of foodstuff infection by S. aureus.

  18. Prevalence, virulence factor genes and antibiotic resistance of Bacillus cereus sensu lato isolated from dairy farms and traditional dairy products

    DEFF Research Database (Denmark)

    Owusu-Kwarteng, James; Wuni, Alhassan; Akabanda, Fortune

    2017-01-01

    Background: B. cereus are of particular interest in food safety and public health because of their capacity to cause food spoilage and disease through the production of various toxins. The aim of this study was to determine the prevalence, virulence factor genes and antibiotic resistance profile...... from 54 positive samples were screened by PCR for the presence of 8 enterotoxigenic genes (hblA, hblC, hblD, nheA, nheB, nheC, cytK and entFM), and one emetic gene (ces). Phenotypic resistance to 15 antibiotics were also determined for 96 B. cereus sensu lato isolates. Results: About 72% (18 of 25 soil...... in 60% (57/96) isolates, 14% (13/96) harboured only one gene, 19% (18/96) whereas 8% possessed none of the NHE genes. The detection rates of cytk, entFM, and ces genes were 75, 67 and 9% respectively. Bacillus cereus s. l. isolates were generally resistant to β-lactam antibiotics such as ampicillin (98...

  19. Reference genes selection and relative expression analysis from Shiraia sp. SUPER-H168 productive of hypocrellin.

    Science.gov (United States)

    Deng, Huaxiang; Gao, Ruijie; Liao, Xiangru; Cai, Yujie

    2016-04-10

    Shiraia bambusicola is an essential pharmaceutical fungus due to its production of hypocrellin with antiviral, antidepressant, and antiretroviral properties. Based on suitable reference gene (RG) normalization, gene expression analysis enables the exploitation of significant genes relative to hypocrellin biosynthesis by quantitative real-time polymerase chain reaction. We selected and assessed nine candidate RGs in the presence and absence of hypocrellin biosynthesis using GeNorm and NormFinder algorithms. After stepwise exclusion of unstable genes, GeNorm analysis identified glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and cytochrome oxidase (CyO) as the most stable expression, while NormFinder determined 18S ribosomal RNA (18S rRNA) as the most appropriate candidate gene for normalization. Tubulin (Tub) was observed to be the least stable gene and should be avoided for relative expression analysis. We further analyzed relative expression levels of essential proteins correlative with hypocrellin biosynthesis, including polyketide synthase (PKS), O-methyltransferase (Omef), FAD/FMN-dependent oxidoreductase (FAD), and monooxygenase (Mono). Compared to PKS, Mono kept a similar expression pattern and simulated PKS expression, while FAD remained constantly expressed. Omef presented lower transcript levels and had no relation to PKS expression. These relative expression analyses will pave the way for further interpretation of the hypocrellin biosynthesis pathway.

  20. Enhanced production of ε-caprolactone by coexpression of bacterial hemoglobin gene in recombinant Escherichia coli expressing cyclohexanone monooxygenase gene.

    Science.gov (United States)

    Lee, Won-Heong; Park, Eun-Hee; Kim, Myoung-Dong

    2014-12-28

    Baeyer-Villiger (BV) oxidation of cyclohexanone to epsilon-caprolactone in a microbial system expressing cyclohexanone monooxygenase (CHMO) can be influenced by not only the efficient regeneration of NADPH but also a sufficient supply of oxygen. In this study, the bacterial hemoglobin gene from Vitreoscilla stercoraria (vhb) was introduced into the recombinant Escherichia coli expressing CHMO to investigate the effects of an oxygen-carrying protein on microbial BV oxidation of cyclohexanone. Coexpression of Vhb allowed the recombinant E. coli strain to produce a maximum epsilon-caprolactone concentration of 15.7 g/l in a fed-batch BV oxidation of cyclohexanone, which corresponded to a 43% improvement compared with the control strain expressing CHMO only under the same conditions.

  1. Characterization of integrons and resistance genes in multidrug-resistant Salmonella enterica isolated from meat and dairy products in Egypt.

    Science.gov (United States)

    Ahmed, Ashraf M; Shimamoto, Toshi; Shimamoto, Tadashi

    2014-10-17

    Foodborne pathogens are a leading cause of illness and death, especially in developing countries. The problem is exacerbated if bacteria attain multidrug resistance. Little is currently known about the extent of antibiotic resistance in foodborne pathogens and the molecular mechanisms underlying this resistance in Africa. Therefore, the current study was carried out to characterize, at the molecular level, the mechanism of multidrug resistance in Salmonella enterica isolated from 1600 food samples (800 meat products and 800 dairy products) collected from different street venders, butchers, retail markets and slaughterhouses in Egypt. Forty-seven out of 69 isolates (68.1%) showed multidrug resistance phenotypes to at least three classes of antimicrobials. The incidence of multidrug-resistant isolates was higher in meat products (37, 69.8%) than in dairy products (10, 62.5%). The multidrug-resistant serovars included, S. enterica serovar Typhimurium (24 isolates, 34.8%), S. enterica serovar Enteritidis, (15 isolates, 21.8%), S. enterica serovar Infantis (7 isolates, 10.1%) and S. enterica non-typable serovar (1 isolate, 1.4%). The highest resistance was to ampicillin (95.7%), then to kanamycin (93.6%), spectinomycin (93.6%), streptomycin (91.5%) and sulfamethoxazole/trimethoprim (91.5%). PCR and DNA sequencing were used to screen and characterize integrons and antibiotic resistance genes and 39.1% and 8.7% of isolates were positive for class 1 and class 2 integrons, respectively. β-lactamase-encoding genes were identified in 75.4% of isolates and plasmid-mediated quinolone resistance genes were identified in 27.5% of isolates. Finally, the florphenicol resistance gene, floR, was identified in 18.8% of isolates. PCR screening identified S. enterica serovar Typhimurium DT104 in both meat and dairy products. This is the first study to report many of these resistance genes in dairy products. This study highlights the high incidence of multidrug-resistant S. enterica in

  2. Production process reproducibility and product quality consistency of transient gene expression in HEK293 cells with anti-PD1 antibody as the model protein.

    Science.gov (United States)

    Ding, Kai; Han, Lei; Zong, Huifang; Chen, Junsheng; Zhang, Baohong; Zhu, Jianwei

    2017-03-01

    Demonstration of reproducibility and consistency of process and product quality is one of the most crucial issues in using transient gene expression (TGE) technology for biopharmaceutical development. In this study, we challenged the production consistency of TGE by expressing nine batches of recombinant IgG antibody in human embryonic kidney 293 cells to evaluate reproducibility including viable cell density, viability, apoptotic status, and antibody yield in cell culture supernatant. Product quality including isoelectric point, binding affinity, secondary structure, and thermal stability was assessed as well. In addition, major glycan forms of antibody from different batches of production were compared to demonstrate glycosylation consistency. Glycan compositions of the antibody harvested at different time periods were also measured to illustrate N-glycan distribution over the culture time. From the results, it has been demonstrated that different TGE batches are reproducible from lot to lot in overall cell growth, product yield, and product qualities including isoelectric point, binding affinity, secondary structure, and thermal stability. Furthermore, major N-glycan compositions are consistent among different TGE batches and conserved during cell culture time.

  3. De novo assembly, gene annotation, and marker discovery in stored-product pest Liposcelis entomophila (Enderlein using transcriptome sequences.

    Directory of Open Access Journals (Sweden)

    Dan-Dan Wei

    Full Text Available BACKGROUND: As a major stored-product pest insect, Liposcelis entomophila has developed high levels of resistance to various insecticides in grain storage systems. However, the molecular mechanisms underlying resistance and environmental stress have not been characterized. To date, there is a lack of genomic information for this species. Therefore, studies aimed at profiling the L. entomophila transcriptome would provide a better understanding of the biological functions at the molecular levels. METHODOLOGY/PRINCIPAL FINDINGS: We applied Illumina sequencing technology to sequence the transcriptome of L. entomophila. A total of 54,406,328 clean reads were obtained and that de novo assembled into 54,220 unigenes, with an average length of 571 bp. Through a similarity search, 33,404 (61.61% unigenes were matched to known proteins in the NCBI non-redundant (Nr protein database. These unigenes were further functionally annotated with gene ontology (GO, cluster of orthologous groups of proteins (COG, and Kyoto Encyclopedia of Genes and Genomes (KEGG databases. A large number of genes potentially involved in insecticide resistance were manually curated, including 68 putative cytochrome P450 genes, 37 putative glutathione S-transferase (GST genes, 19 putative carboxyl/cholinesterase (CCE genes, and other 126 transcripts to contain target site sequences or encoding detoxification genes representing eight types of resistance enzymes. Furthermore, to gain insight into the molecular basis of the L. entomophila toward thermal stresses, 25 heat shock protein (Hsp genes were identified. In addition, 1,100 SSRs and 57,757 SNPs were detected and 231 pairs of SSR primes were designed for investigating the genetic diversity in future. CONCLUSIONS/SIGNIFICANCE: We developed a comprehensive transcriptomic database for L. entomophila. These sequences and putative molecular markers would further promote our understanding of the molecular mechanisms underlying

  4. Gene detection and toxin production evaluation of hemolysin BL of Bacillus cereus isolated from milk and dairy products marketed in Brazil.

    Science.gov (United States)

    Reis, Andre L S; Montanhini, Maike T M; Bittencourt, Juliana V M; Destro, Maria T; Bersot, Luciano S

    2013-12-01

    Bacillus cereusis an ubiquitous, spore-forming bacteria that can survive pasteurization and the majority of the heating processes used in the dairy industry. Besides, it is a pathogen responsible for different types of food poisoning. One type of foodborne disease caused by B.cereusis the diarrheal syndrome, which is caused by the ingestion of vegetative cells producing toxins in the small intestine. One virulence factor for the diarrheal syndrome is the toxin hemolysin BL (HBL), a three-component protein formed by the L1, L2 and B components. In order to evaluate the presence of diarrheal strains isolated from milk and dairy products, 63 B. cereus isolates were obtained from 260 samples of UHT milk, pasteurized milk and powdered milk, sold in commercial establishments and from different brands. The isolates were subjected to the Polymerase Chain Reaction (PCR) for the detection of the encoding genes for the L1, L2 and B components and the toxin production capacity were evaluated with an immunoassay. A total of 23 [36.5%] isolates were identified carrying simultaneously the three tested genes, from which, 20 [86.9%] showed toxigenic capacity. 26 [41.3%] isolates did not carry any of genes tested and the other 14 [22.2%] were positive for one or two of them. The results showed a high toxigenic capacity among the B. cereus isolates able to produce the HBL, indicating a potential risk for consumers.

  5. Gene detection and toxin production evaluation of hemolysin BL of Bacillus cereus isolated from milk and dairy products marketed in Brazil

    Directory of Open Access Journals (Sweden)

    Andre L.S. Reis

    2013-12-01

    Full Text Available Bacillus cereusis an ubiquitous, spore-forming bacteria that can survive pasteurization and the majority of the heating processes used in the dairy industry. Besides, it is a pathogen responsible for different types of food poisoning. One type of foodborne disease caused by B.cereusis the diarrheal syndrome, which is caused by the ingestion of vegetative cells producing toxins in the small intestine. One virulence factor for the diarrheal syndrome is the toxin hemolysin BL (HBL, a three-component protein formed by the L1, L2 and B components. In order to evaluate the presence of diarrheal strains isolated from milk and dairy products, 63 B. cereus isolates were obtained from 260 samples of UHT milk, pasteurized milk and powdered milk, sold in commercial establishments and from different brands. The isolates were subjected to the Polymerase Chain Reaction (PCR for the detection of the encoding genes for the L1, L2 and B components and the toxin production capacity were evaluated with an immunoassay. A total of 23 [36.5%] isolates were identified carrying simultaneously the three tested genes, from which, 20 [86.9%] showed toxigenic capacity. 26 [41.3%] isolates did not carry any of genes tested and the other 14 [22.2%] were positive for one or two of them. The results showed a high toxigenic capacity among the B. cereus isolates able to produce the HBL, indicating a potential risk for consumers.

  6. Engineering of Corynebacterium glutamicum to Enhance L-ornithine Production by Gene Knockout and Comparative Proteomic Analysis

    Institute of Scientific and Technical Information of China (English)

    卢冬梅; 刘建忠; 毛宗万

    2012-01-01

    Engineered Corynebacterium glutamicum was constructed for L-ornithine production by disrupting genes of argF and proB to prevent the flux away from L-ornithine.Effect of the inactivation of 2-oxoglutarate de-hydrogenase complex(ODHC) on L-ornithine production was also investigated.It was found that the inactivation of ODHC by knockout of the kgd gene enhanced L-ornithine production.The engineered C.glutamicum ATCC13032(ΔargFΔproBΔkgd) produced L-ornithine up to 4.78 g·L-1 from 0.24 g·L-1 of the wild-type strain.In order to understand the mechanism of L-ornithine production in C.glutamicum ATCC13032(ΔargFΔproBΔkgd) and find out new strategies for further enhancing L-ornithine production,the comparative proteome between the wild-type and the engineered strain was analyzed.L-Ornithine overproduction in the engineered strain was related to the up-regulation of the expression levels of enzymes involved in L-ornithine biosynthesis pathway and down-regulation of the expression levels of proteins involved in pentose phosphate pathway.The overexpression of genes in the upstream pathway of glutamate to increase the availability of endogenous glutamate may further in-crease ornithine production in the engineered C.glutamicum and the ornithine synthesis enzymes(ArgCJBD) may not be the limiting enzymes in the engineered C.glutamicum.

  7. Ocular expression and distribution of products of the POAG-associated chromosome 9p21 gene region.

    Directory of Open Access Journals (Sweden)

    Glyn Chidlow

    Full Text Available It has recently been shown that there are highly significant associations for common single nucleotide polymorphisms (SNPs near the CDKN2B-AS1 gene region at the 9p21 locus with primary open angle glaucoma (POAG, a leading cause of irreversible blindness. This gene region houses the CDKN2B/p15(INK4B , CDKN2A/p16(INK4A and p14ARF (rat equivalent, p19(ARF tumour suppressor genes and is adjacent to the S-methyl-5'-thioadenosine phosphorylase (MTAP gene. In order to understand the ocular function of these genes and, therefore, how they may be involved in the pathogenesis of POAG, we studied the distribution patterns of each of their products within human and rat ocular tissues. MTAP mRNA was detected in the rat retina and optic nerve and its protein product was localised to the corneal epithelium, trabecular meshwork and retinal glial cells in both human and rat eyes. There was a very low level of p16(INK4A mRNA present within the rat retina and slightly more in the optic nerve, although no protein product could be detected in either rat or human eyes with any of the antibodies tested. P19(ARF mRNA was likewise only present at very low levels in rat retina and slightly higher levels in the optic nerve. However, no unambiguous evidence was found to indicate expression of specific P19(ARF/p14(ARF proteins in either rat or human eyes, respectively. In contrast, p15(INK4B mRNA was detected in much higher amounts in both retina and optic nerve compared with the other genes under analysis. Moreover, p15(INK4B protein was clearly localised to the retinal inner nuclear and ganglion cell layers and the corneal epithelium and trabecular meshwork in rat and human eyes. The presented data provide the basis for future studies that can explore the roles that these gene products may play in the pathogenesis of glaucoma and other models of optic nerve damage.

  8. Microbial production of indolylglucosinolate through engineering of a multi-gene pathway in a versatile yeast expression platform

    DEFF Research Database (Denmark)

    Mikkelsen, Michael Dalgaard; Buron, Line Due; Salomonsen, Bo;

    2012-01-01

    Epidemiological studies have shown that consumption of cruciferous vegetables, such as, broccoli and cabbages, is associated with a reduced risk of developing cancer. This phenomenon has been attributed to specific glucosinolates among the ∼30 glucosinolates that are typically present as natural...... products characteristic of cruciferous plants. Accordingly, there has been a strong interest to produce these compounds in microbial cell factories as it will allow production of selected beneficial glucosinolates. We have developed a versatile platform for stable expression of multi-gene pathways...... in the yeast, Saccharomyces cerevisiae. Introduction of the seven-step pathway of indolylglucosinolate from Arabidopsis thaliana to yeast resulted in the first successful production of glucosinolates in a microbial host. The production of indolylglucosinolate was further optimized by substituting supporting...

  9. Production of DNA microarray and expression analysis of genes from Xylella fastidiosa in different culture media

    Directory of Open Access Journals (Sweden)

    Regiane de Fátima Travensolo

    2009-06-01

    Full Text Available DNA Microarray was developed to monitor the expression of many genes from Xylella fastidiosa, allowing the side by-side comparison of two situations in a single experiment. The experiments were performed using X. fastidiosa cells grown in two culture media: BCYE and XDM2. The primers were synthesized, spotted onto glass slides and the array was hybridized against fluorescently labeled cDNAs. The emitted signals were quantified, normalized and the data were statistically analyzed to verify the differentially expressed genes. According to the data, 104 genes were differentially expressed in XDM2 and 30 genes in BCYE media. The present study showed that DNA microarray technique efficiently differentiate the expressed genes under different conditions.DNA Microarray foi desenvolvida para monitorar a expressão de muitos genes de Xylella fastidiosa, permitindo a comparação de duas situações distintas em um único experimento. Os experimentos foram feitos utilizando células de X. fastidiosa cultivada em dois meios de cultura: BCYE e XDM2. Pares de oligonucleotídeos iniciadores foram sintetizados, depositados em lâminas de vidro e o arranjo foi hibridizado contra cDNAs marcados fluorescentemente. Os sinais emitidos foram quantificados, normalizados e os dados foram estatisticamente analisados para verificar os genes diferencialmente expressos. De acordo com nossos dados, 104 genes foram diferencialmente expressos para o meio de cultura XDM2 e 30 genes para o BCYE. No presente estudo, nós demonstramos que a técnica de DNA microarrays eficientemente diferencia genes expressos sob diferentes condições de cultivo.

  10. Functional genomics reveals that a compact terpene synthase gene family can account for terpene volatile production in apple.

    Science.gov (United States)

    Nieuwenhuizen, Niels J; Green, Sol A; Chen, Xiuyin; Bailleul, Estelle J D; Matich, Adam J; Wang, Mindy Y; Atkinson, Ross G

    2013-02-01

    Terpenes are specialized plant metabolites that act as attractants to pollinators and as defensive compounds against pathogens and herbivores, but they also play an important role in determining the quality of horticultural food products. We show that the genome of cultivated apple (Malus domestica) contains 55 putative terpene synthase (TPS) genes, of which only 10 are predicted to be functional. This low number of predicted functional TPS genes compared with other plant species was supported by the identification of only eight potentially functional TPS enzymes in apple 'Royal Gala' expressed sequence tag databases, including the previously characterized apple (E,E)-α-farnesene synthase. In planta functional characterization of these TPS enzymes showed that they could account for the majority of terpene volatiles produced in cv Royal Gala, including the sesquiterpenes germacrene-D and (E)-β-caryophyllene, the monoterpenes linalool and α-pinene, and the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene. Relative expression analysis of the TPS genes indicated that floral and vegetative tissues were the primary sites of terpene production in cv Royal Gala. However, production of cv Royal Gala floral-specific terpenes and TPS genes was observed in the fruit of some heritage apple cultivars. Our results suggest that the apple TPS gene family has been shaped by a combination of ancestral and more recent genome-wide duplication events. The relatively small number of functional enzymes suggests that the remaining terpenes produced in floral and vegetative and fruit tissues are maintained under a positive selective pressure, while the small number of terpenes found in the fruit of modern cultivars may be related to commercial breeding strategies.

  11. Functional Genomics Reveals That a Compact Terpene Synthase Gene Family Can Account for Terpene Volatile Production in Apple1[W

    Science.gov (United States)

    Nieuwenhuizen, Niels J.; Green, Sol A.; Chen, Xiuyin; Bailleul, Estelle J.D.; Matich, Adam J.; Wang, Mindy Y.; Atkinson, Ross G.

    2013-01-01

    Terpenes are specialized plant metabolites that act as attractants to pollinators and as defensive compounds against pathogens and herbivores, but they also play an important role in determining the quality of horticultural food products. We show that the genome of cultivated apple (Malus domestica) contains 55 putative terpene synthase (TPS) genes, of which only 10 are predicted to be functional. This low number of predicted functional TPS genes compared with other plant species was supported by the identification of only eight potentially functional TPS enzymes in apple ‘Royal Gala’ expressed sequence tag databases, including the previously characterized apple (E,E)-α-farnesene synthase. In planta functional characterization of these TPS enzymes showed that they could account for the majority of terpene volatiles produced in cv Royal Gala, including the sesquiterpenes germacrene-D and (E)-β-caryophyllene, the monoterpenes linalool and α-pinene, and the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene. Relative expression analysis of the TPS genes indicated that floral and vegetative tissues were the primary sites of terpene production in cv Royal Gala. However, production of cv Royal Gala floral-specific terpenes and TPS genes was observed in the fruit of some heritage apple cultivars. Our results suggest that the apple TPS gene family has been shaped by a combination of ancestral and more recent genome-wide duplication events. The relatively small number of functional enzymes suggests that the remaining terpenes produced in floral and vegetative and fruit tissues are maintained under a positive selective pressure, while the small number of terpenes found in the fruit of modern cultivars may be related to commercial breeding strategies. PMID:23256150

  12. Shiga toxin-producing Escherichia coli strains isolated from dairy products - Genetic diversity and virulence gene profiles.

    Science.gov (United States)

    Douëllou, T; Delannoy, S; Ganet, S; Mariani-Kurkdjian, P; Fach, P; Loukiadis, E; Montel, Mc; Thevenot-Sergentet, D

    2016-09-02

    Shiga toxin-producing Escherichia coli (STEC) are widely recognized as pathogens causing food borne disease. Here we evaluate the genetic diversity of 197 strains, mainly STEC, from serotypes O157:H7, O26:H11, O103:H2, O111:H8 and O145:28 and compared strains recovered in dairy products against strains from human, meat and environment cases. For this purpose, we characterized a set of reference-collection STEC isolates from dairy products by PFGE DNA fingerprinting and a subset of these by virulence-gene profiling. PFGE profiles of restricted STEC total DNA showed high genomic variability (0.9976 on Simpson's discriminatory index), enabling all dairy isolates to be differentiated. High-throughput real-time PCR screening of STEC virulence genes were applied on the O157:H7 and O26:H11 STEC isolates from dairy products and human cases. The virulence gene profiles of dairy and human STEC strains were similar. Nevertheless, frequency-wise, stx1 was more prevalent among dairy O26:H11 isolates than in human cases ones (87% vs. 44%) while stx2 was more prevalent among O26:H11 human isolates (23% vs. 81%). For O157:H7 isolates, stx1 (0% vs. 39%), nleF (40% vs 94%) and Z6065 (40% vs 100%) were more prevalent among human than dairy strains. Our data point to differences between human and dairy strains but these differences were not sufficient to associate PFGE and virulence gene profiles to a putative lower pathogenicity of dairy strains based on their lower incidence in disease. Further comparison of whole-genome expression and virulence gene profiles should be investigated in cheese and intestinal tract samples.

  13. Ectopic Expression of CDF3 Genes in Tomato Enhances Biomass Production and Yield under Salinity Stress Conditions

    Directory of Open Access Journals (Sweden)

    Begoña Renau-Morata

    2017-05-01

    Full Text Available Cycling Dof Factor (CDF transcription factors (TFs are involved in multiple processes related to plant growth and development. A member of this family, CDF3, has recently been linked in Arabidopsis to the regulation of primary metabolism and abiotic stress responses, but its role in crop production under stress is still unknown. In this study, we characterized tomato plants overexpressing the CDF3 genes from Arabidopsis and tomato and analyzed their effects on growth and yield under salinity, additionally gaining deeper insights into the molecular function of these TFs. Our results provide evidence for higher biomass production and yield in the 35S::AtCDF3 and 35S::SlCDF3 plants, likely due to a higher photosynthetic capacity resulting in increased sucrose availability. Transcriptome analysis revealed that CDF3 genes regulate a set of genes involved in redox homeostasis, photosynthesis performance and primary metabolism that lead to enhanced biomass production. Consistently, metabolomic profiling revealed that CDF3 evokes changes in the primary metabolism triggering enhanced nitrogen assimilation, and disclosed that the amount of some protective metabolites including sucrose, GABA and asparagine were higher in vegetative tissues of CDF3 overexpressing plants. Altogether these changes improved performance of 35S::AtCDF3 and 35S::SlCDF3 plants under salinity conditions. Moreover, the overexpression of CDF3 genes modified organic acid and sugar content in fruits, improving variables related to flavor perception and fruit quality. Overall, our results associate the CDF3 TF with a role in the control of growth and C/N metabolism, and highlight that overexpression of CDF3 genes can substantially improve plant yield.

  14. Isoepoxydon dehydrogenase (idh) gene expression in relation to patulin production by Penicillium expansum under different temperature and atmosphere.

    Science.gov (United States)

    De Clercq, N; Vlaemynck, G; Van Pamel, E; Van Weyenberg, S; Herman, L; Devlieghere, F; De Meulenaer, B; Van Coillie, E

    2016-03-02

    Penicillium expansum growth and patulin production occur mainly at post-harvest stage during the long-term storage of apples. Low temperature in combination with reduced oxygen concentrations is commonly applied as a control strategy to extend apple shelf life and supply the market throughout the year. Our in vitro study investigated the effect of temperature and atmosphere on expression of the idh gene in relation to the patulin production by P. expansum. The idh gene encodes the isoepoxydon dehydrogenase enzyme, a key enzyme in the patulin biosynthesis pathway. First, a reverse transcription real-time PCR (RT-qPCR) method was optimized to measure accurately the P. expansum idh mRNA levels relative to the mRNA levels of three reference genes (18S, β-tubulin, calmodulin), taking into account important parameters such as PCR inhibition and multiple reference gene stability. Subsequently, two P. expansum field isolates and one reference strain were grown on apple puree agar medium (APAM) under three conditions of temperature and atmosphere: 20 °C - air, 4 °C - air and 4 °C - controlled atmosphere (CA; 3% O2). When P. expansum strains reached a 0.5 and 2.0 cm colony diameter, idh expression and patulin concentrations were determined by means of the developed RT-qPCR and an HPLC-UV method, respectively. The in vitro study showed a clear reduction in patulin production and down-regulation of the idh gene expression when P. expansum was grown under 4 °C - CA. The results suggest that stress (low temperature and oxygen level) caused a delay of the fungal metabolism rather than a complete inhibition of toxin biosynthesis. A good correlation was found between the idh expression and patulin production, corroborating that temperature and atmosphere affected patulin production by acting at the transcriptional level of the idh gene. Finally, a reliable RT-qPCR can be considered as an alternative tool to investigate the effect of control strategies on the toxin formation in

  15. Enhancement of welan gum production in Sphingomonas sp. HT-1 via heterologous expression of Vitreoscilla hemoglobin gene.

    Science.gov (United States)

    Liu, Xiaoliu; Zhu, Ping; Jiang, Ruifan; Wu, Lingtian; Feng, Xiaohai; Li, Sha; Xu, Hong

    2017-01-20

    Welan gum is a microbial polysaccharide produced by Sphingomonas sp. Its production is limited by the dissolved oxygen levels in the highly viscous fermentation. A strategy of heterologous expression of the Vitreoscilla hemoglobin gene in Sphingomonas sp. HT-1 was investigated to alleviate oxygen limitation and improve the yield of welan gum. Ultimately, the welan gum production increased from 25.3g/L to 34.6g/L, whereas the rheological behavior of welan gum solutions remained virtually unchanged. The transcriptional levels of the key genes in the electron transfer chain, TCA cycle and welan gum synthesis pathway, as well as ATP level revealed that the VHb expression in Sphingomonas sp. HT-1 enhanced welan gum biosynthesis by improving respiration and ATP supply. This study would pave the genetic manipulation way for enhancing welan gum yield, and it's also of great importance for the industrial applications of welan gum under harsh conditions.

  16. Elevated PC responsive B cells and anti-PC antibody production in transgenic mice harboring anti-PC immunoglobulin genes.

    Science.gov (United States)

    Pinkert, C A; Manz, J; Linton, P J; Klinman, N R; Storb, U

    1989-12-01

    The rearrangement of heavy and light chain immunoglobulin genes is necessary for the production of functional antibody molecules. The myeloma MOPC 167 produces specific antibodies to the antigen phosphorylcholine (PC), which is present on bacterial surfaces, fungi and other environmental contaminants. Rearranged heavy and light chain immunoglobulin genes cloned from MOPC 167 were microinjected into mouse eggs. Within the resulting transgenic mice, expression of the transgenes were limited to lymphoid tissues. Transgenic mice produced elevated levels of anti-PC antibodies constitutively, at 16 days of age, when normal non-transgenic mice were not fully immunocompetent. A triggering antigenic stimulus was not necessary to evoke anti-PC immunoglobulin production. Additionally, the frequency of PC-responsive B cells in these transgenic mice was further increased upon specific immunization.

  17. Heterologous expression of Mus musculus immunoresponsive gene 1 (irg1 in Escherichia coli results in itaconate production

    Directory of Open Access Journals (Sweden)

    Kiira S Vuoristo

    2015-08-01

    Full Text Available Itaconic acid, a C5-dicarboxylic acid, is a potential biobased building block for the polymer industry. It is obtained from the citric acid cycle by decarboxylation of cis-aconitic acid. This reaction is catalysed by CadA in the native itaconic acid producer Aspergillus terreus. Recently, another enzyme encoded by the mammalian immunoresponsive gene 1 (irg1, was found to decarboxylate cis-aconitate to itaconate in vitro. We show that heterologous expression of irg1 enabled itaconate production in E. coli with production titres up to 560 mg/L.

  18. Oxalic acid production by citric acid-producing Aspergillus niger overexpressing the oxaloacetate hydrolase gene oahA.

    Science.gov (United States)

    Kobayashi, Keiichi; Hattori, Takasumi; Honda, Yuki; Kirimura, Kohtaro

    2014-05-01

    The filamentous fungus Aspergillus niger is used worldwide in the industrial production of citric acid. However, under specific cultivation conditions, citric acid-producing strains of A. niger accumulate oxalic acid as a by-product. Oxalic acid is used as a chelator, detergent, or tanning agent. Here, we sought to develop oxalic acid hyperproducers using A. niger as a host. To generate oxalic acid hyperproducers by metabolic engineering, transformants overexpressing the oahA gene, encoding oxaloacetate hydrolase (OAH; EC 3.7.1.1), were constructed in citric acid-producing A. niger WU-2223L as a host. The oxalic acid production capacity of this strain was examined by cultivation of EOAH-1 under conditions appropriate for oxalic acid production with 30 g/l glucose as a carbon source. Under all the cultivation conditions tested, the amount of oxalic acid produced by EOAH-1, a representative oahA-overexpressing transformant, exceeded that produced by A. niger WU-2223L. A. niger WU-2223L and EOAH-1 produced 15.6 and 28.9 g/l oxalic acid, respectively, during the 12-day cultivation period. The yield of oxalic acid for EOAH-1 was 64.2 % of the maximum theoretical yield. Our method for oxalic acid production gave the highest yield of any study reported to date. Therefore, we succeeded in generating oxalic acid hyperproducers by overexpressing a single gene, i.e., oahA, in citric acid-producing A. niger as a host.

  19. Effects of carbon, nitrogen and ambient pH on patulin production and related gene expression in Penicillium expansum.

    Science.gov (United States)

    Zong, Yuanyuan; Li, Boqiang; Tian, Shiping

    2015-08-03

    Patulin, a potent mycotoxin which can cause serious health concerns, is mainly produced in foods by Penicillium expansum. Environmental factors play important roles in regulating biosynthesis of mycotoxins; however, information about the effects of environmental factors on patulin production and the involved mechanisms in P. expansum is limited. Here, we investigated the effects of different carbon (C) and nitrogen (N) sources, and ambient pH on patulin production in three P. expansum strains T01, M1 and Pe21, and the expression profile of 15 genes involved in patulin biosynthetic pathway. It was found that C and N sources and pH had great influence on patulin production in P. expansum. In general, patulin production of all three P. expansum strains showed similar trends under different C and N sources and pH conditions, though there were some differences in the optimal conditions among these strains. Glucose-containing sugars, complex N sources, and acidic conditions were favorable conditions for patulin production. The results of RT-qPCR showed that the relative expressions of most of the patulin genes were up-regulated under patulin-permissive conditions, indicating that patulin biosynthesis was mainly regulated at transcriptional level by these environmental factors. These findings will provide useful information to better understand the regulation mechanisms of patulin biosynthesis, and be helpful in developing effective means for controlling patulin contamination.

  20. FUM Gene Expression Profile and Fumonisin Production by Fusarium verticillioides Inoculated in Bt and Non-Bt Maize

    Science.gov (United States)

    Rocha, Liliana O.; Barroso, Vinícius M.; Andrade, Ludmila J.; Pereira, Gustavo H. A.; Ferreira-Castro, Fabiane L.; Duarte, Aildson P.; Michelotto, Marcos D.; Correa, Benedito

    2016-01-01

    This study aimed to determine the levels of fumonisins produced by Fusarium verticillioides and FUM gene expression on Bt (Bacillus thuringiensis) and non-Bt maize, post harvest, during different periods of incubation. Transgenic hybrids 30F35 YG, 2B710 Hx and their isogenic (30F35 and 2B710) were collected from the field and a subset of 30 samples selected for the experiments. Maize samples were sterilized by gamma radiation at a dose of 20 kGy. Samples were then inoculated with F. verticillioides and analyzed under controlled conditions of temperature and relative humidity for fumonisin B1 and B2 (FB1 and FB2) production and FUM1, FUM3, FUM6, FUM7, FUM8, FUM13, FUM14, FUM15, and FUM19 expression. 2B710 Hx and 30F35 YG kernel samples were virtually intact when compared to the non-Bt hybrids that came from the field. Statistical analysis showed that FB1 production was significantly lower in 30F35 YG and 2B710 Hx than in the 30F35 and 2B710 hybrids (P 0.05). The kernel injuries observed in the non-Bt samples have possibly facilitated F. verticillioides penetration and promoted FB1 production under controlled conditions. FUM genes were expressed by F. verticillioides in all of the samples. However, there was indication of lower expression of a few FUM genes in the Bt hybrids; and a weak association between FB1 production and the relative expression of some of the FUM genes were observed in the 30F35 YG hybrid. PMID:26779158

  1. FUM gene expression profile and fumonisin production by Fusarium verticillioides inoculated in Bt and non-Bt maize

    Directory of Open Access Journals (Sweden)

    Liliana Oliveira Rocha

    2016-01-01

    Full Text Available This study aimed to determine the levels of fumonisins produced by F. verticillioides and FUM gene expression on Bt (Bacillus thuringiensis and non-Bt maize, post harvest, during different periods of incubation. Transgenic hybrids 30F35 YG, 2B710 Hx and their isogenic (30F35 and 2B710 were collected from the field and a subset of 30 samples selected for the experiments. Maize samples were sterilized by gamma radiation at a dose of 20 kGy. Samples were then inoculated with Fusarium verticillioides and analysed under controlled conditions of temperature and relative humidity for fumonisin B1 and B2 (FB¬1 and FB2 production and FUM1, FUM3, FUM6, FUM7, FUM8, FUM13, FUM14, FUM15 and FUM19 expression. 2B710 Hx and 30F35 YG kernel samples were virtually intact when compared to the non-Bt hybrids that came from the field. Statistical analysis showed that FB¬1 production was significantly lower in 30F35 YG and 2B710 Hx than in the 30F35 and 2B710 hybrids (P 0.05. The kernel injuries observed in the non-Bt samples have possibly facilitated F. verticillioides penetration and promoted FB1 production under controlled conditions. FUM genes were expressed by F. verticillioides in all of the samples. However, there was indication of lower expression of a few FUM genes in the Bt hybrids; and a weak association between FB1 production and the relative expression of some of the FUM genes were observed in the 30F35 YG hybrid.

  2. Production of individualized V gene databases reveals high levels of immunoglobulin genetic diversity

    Science.gov (United States)

    Corcoran, Martin M.; Phad, Ganesh E.; Bernat, Néstor Vázquez; Stahl-Hennig, Christiane; Sumida, Noriyuki; Persson, Mats A. A.; Martin, Marcel; Hedestam, Gunilla B. Karlsson

    2016-12-01

    Comprehensive knowledge of immunoglobulin genetics is required to advance our understanding of B cell biology. Validated immunoglobulin variable (V) gene databases are close to completion only for human and mouse. We present a novel computational approach, IgDiscover, that identifies germline V genes from expressed repertoires to a specificity of 100%. IgDiscover uses a cluster identification process to produce candidate sequences that, once filtered, results in individualized germline V gene databases. IgDiscover was tested in multiple species, validated by genomic cloning and cross library comparisons and produces comprehensive gene databases even where limited genomic sequence is available. IgDiscover analysis of the allelic content of the Indian and Chinese-origin rhesus macaques reveals high levels of immunoglobulin gene diversity in this species. Further, we describe a novel human IGHV3-21 allele and confirm significant gene differences between Balb/c and C57BL6 mouse strains, demonstrating the power of IgDiscover as a germline V gene discovery tool.

  3. The gene bap, involved in biofilm production, is present in Staphylococcus spp. strains from nosocomial infections.

    Science.gov (United States)

    Potter, Amina; Ceotto, Hilana; Giambiagi-Demarval, Marcia; dos Santos, Kátia Regina Netto; Nes, Ingolf F; Bastos, Maria do Carmo de Freire

    2009-06-01

    This study analyzed ten strains of coagulase-negative staphylococci (CNS) involved in nosocomial infections in three Brazilian hospitals. Their antibiotic susceptibility profile showed that most strains exhibited multiple antibiotic resistance and possessed the mecA gene. The ability of these strains to adhere to polystyrene microtiter plates was also tested and nine of them proved to be biofilm producers at least in one of the three conditions tested: growth in TSB, in TSB supplemented with NaCl, or in TSB supplemented with glucose. The presence of the bap gene, which codes for the biofilm-associated protein (Bap), was investigated in all ten strains by PCR. AU strains were bop-positive and DNA sequencing experiments confirmed that the fragments amplified were indeed part of a bap gene. The presence of the icaA gene, one of the genes involved in polysaccharide intercellular adhesin (PIA) formation, was also detected by PCR in eight of the ten strains tested. The two icaA-negative strains were either weak biofilm producer or no biofilm producer, although they were bop-positive. To our knowledge, this is the first report demonstrating the presence of the bap gene in nosocomial isolates of CNS, being also the first report on the presence of this gene in Staphylococcus haemolyticus and S. cohnii.

  4. Occurrence and Diversity of Tetracycline Resistance Genes in Lagoons and Groundwater Underlying Two Swine Production Facilities

    Science.gov (United States)

    Chee-Sanford, J. C.; Aminov, R.I.; Krapac, I.J.; Garrigues-Jeanjean, N.; Mackie, R.I.

    2001-01-01

    In this study, we used PCR typing methods to assess the presence of tetracycline resistance determinants conferring ribosomal protection in waste lagoons and in groundwater underlying two swine farms. All eight classes of genes encoding this mechanism of resistance [tet(O), tet(Q), tet(W), tet(M), tetB(P), tet(S), tet(T), and otrA] were found in total DNA extracted from water of two lagoons. These determinants were found to be seeping into the underlying groundwater and could be detected as far as 250 m downstream from the lagoons. The identities and origin of these genes in groundwater were confirmed by PCR-denaturing gradient gel electrophoresis and sequence analyses. Tetracycline-resistant bacterial isolates from groundwater harbored the tet(M) gene, which was not predominant in the environmental samples and was identical to tet(M) from the lagoons. The presence of this gene in some typical soil inhabitants suggests that the vector of antibiotic resistance gene dissemination is not limited to strains of gastrointestinal origin carrying the gene but can be mobilized into the indigenous soil microbiota. This study demonstrated that tet genes occur in the environment as a direct result of agriculture and suggested that groundwater may be a potential source of antibiotic resistance in the food chain.

  5. Associations of the variation in the porcine myogenin gene with muscle fibre characteristics, lean meat production and meat quality traits.

    Science.gov (United States)

    Kim, J M; Choi, B D; Kim, B C; Park, S S; Hong, K C

    2009-04-01

    Pig breeding is aimed at improving lean meat production ability as well as meat quality, and muscle fibre characteristics may be important for enhancing these traits. Therefore, new molecular markers have been demanded for selecting lean meat production ability and meat quality in live animals. Myogenin belongs to the MyoD gene family, and is a candidate gene responsible for muscle fibre characteristics. We identified a new single nucleotide polymorphism (SNP) site in the 5' upstream region of the myogenin gene (nucleotides C and T). A total of 252 pigs of three breeds were genotyped by polymerase chain reaction-restriction fragment length polymorphism using BspCNI. Additionally, they were genotyped for the previously detected MspI site in the 3'-flanking region (alleles A and B). The CCBB diplotype had the highest frequency over breeds, followed by TCBB and CCAB. The other diplotypes were not found in studied pigs. Association analysis performed for the markers found that the TCBB diplotype has desirable effects on the total number of fibres (p lean meat production ability with good meat quality.

  6. Secretive Expression of Insect Antifungal Peptide-Encoded Genes in Pichia pastoris and Activity Assay of the Products

    Institute of Scientific and Technical Information of China (English)

    SANG Yan-xia; DENG Xiao-juan; YANG Wan-ying; WANG Wen-xian; WEN Shuo-yang; LIU Wen-quan; HUANG Ya-dong; CAO Yang

    2007-01-01

    The antifungal peptides, drosomycin (Drs) and its isoform drosomycin-like C (Drs-lC) from Drosophila melanogaster and Thanatin from Podisus maculiventris, have potent activity with broad spectrum against filamentous fungi. Secretive expression of these genes in yeasts makes it possible to utilize the supernatants of yeast culture as protective reagents on fruit, vegetable, food and other agricultural products. So the study of effective secretion by yeast expression system is of great importance. Three genes, Drs, Drs-lC, and Thanatin, were cloned into pPICZαA and the recombinant vectors,pPICZαA-Drs, pPICZαA-Drs-IC, and pPICZαA-Thanatin were transformed into Pichia pastoris by the electric transfer method. The recombinant P. pastoris, which was screened by phenotype selection and PCR amplification, wasinduced to express antifungal peptide by methanol. The expressive products of the three recombinants showed antifungal activity against 5 out of 6 test fungi strains, and the products of Thanatin also had strong activity against the tested bacteria. The three antifungal peptide genes, Drs, Drs-lC, and Thanatin, were constructed into yeast P. pastoris. The expressed peptides were successfully secreted into the culture medium and exhibited potent activities against the test strains.

  7. Exonuclease III and the catalase hydroperoxidase II in Escherichia coli are both regulated by the katF gene product

    Energy Technology Data Exchange (ETDEWEB)

    Sak, B.D.; Eisenstark, A.; Touati, D.

    1989-05-01

    The levels of both exonuclease III (exo III, product of xthA) and hydroperoxidase II (HP-II, product of katE) activity in Escherichia coli were influenced by a functional katF gene. The katF gene product is also necessary for synthesis of HP-II. Mutations in either katF or xthA, but not katE, result in sensitivity to H/sub 2/O/sub 2/ and near-UV (300-400 nm) radiation. Exo III, encoded by the xthA locus, recognizes and removes nucleoside 5'-monophosphates near apurinic and apyrimidinic sites in damaged DNA. Extracts of katF mutant strains had little detectable exo III activity. When a katF+ plasmid was introduced into the katF mutant, exo III activity exceeded wild-type levels. We propose that the katF gene is a trans-acting positive regulator of exo III and HP-II enzymes, both of which are involved in cellular recovery from oxidative damage.

  8. Analysis of the L1 gene product of human papillomavirus type 16 by expression in a vaccinia virus recombinant.

    Science.gov (United States)

    Browne, H M; Churcher, M J; Stanley, M A; Smith, G L; Minson, A C

    1988-06-01

    The L1 open reading frame of human papillomavirus type 16 (HPV16) has been expressed in vaccinia virus under the control of both the 7.5K early and late promoter, and the 4b major late promoter. Antibodies to a beta-galactosidase fusion protein containing a C-terminal portion of the HPV16 L1 gene product were used to compare the levels of L1 expression in the two recombinants, and showed that greater levels of expression were obtained when the gene was placed under the control of the 4b late promoter. Immunofluorescence studies revealed a nuclear location of the L1 gene product when expressed in vaccinia virus. Antibodies to the beta-galactosidase fusion protein detected a major polypeptide species of 57K and a minor species of 64K in Western blots of recombinant-infected cell lysates. The 64K species was not detected when cells were infected in the presence of tunicamycin, indicating that the primary translation product of the HPV16 L1 open reading frame is modified by N-linked glycosylation when expressed in vaccinia virus. Whereas antibodies to HPV16 L1 fusion proteins and to a peptide containing amino acids from the C terminus of HPV16 L1 reacted well in Western blots with the HPV16 L1 target expressed in vaccinia virus, no reactivity was observed with antibodies to bovine papillomavirus type 1 particles or to a HPV6b fusion protein.

  9. The Effect of IL-4 Gene Polymorphisms on Cytokine Production in Patients with Chronic Periodontitis and in Healthy Controls

    Directory of Open Access Journals (Sweden)

    Jirina Bartova

    2014-01-01

    Full Text Available Chronic periodontitis (CP is an inflammatory disease of the teeth-supporting tissues in which genetic predisposition, dental plaque bacteria, and immune mechanisms all play important roles. The aim of this study was to evaluate the occurrence of IL-4 gene polymorphisms in chronic periodontitis and to investigate the association between polymorphisms and cytokines production after bacterial stimulation. Sixty-two subjects (47 CP patients and 15 healthy controls with detected two polymorphisms in the IL-4 gene (-590C/T and intron 3 VNTR were examined. Production of cytokines (IL-1α, IL-1β, IL-4, IL-5, IL-6, IL-10, IL-17, TNFα, INFγ, and VEGF was studied after in vitro stimulation of isolated peripheral blood by mitogens (Pokeweed mitogen, Concanavalin A, dental plaque bacteria (Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis, and Prevotella intermedia, and Heat Shock Protein (HSP 70 by the Luminex multiplex cytokine analysis system. The results were correlated with IL-4 genotypes in patients with CP and healthy controls. The mononuclear cells isolated from peripheral blood of CP patients with selected IL-4 polymorphisms significantly altered the production of IFNγ, IL-10, IL-1β, IL-1α, TNFα, and IL-6 after stimulation by HSP 70 or selected bacteria (from P<0.001 to P<0.05. IL-4 gene polymorphisms may influence the function of mononuclear cells to produce not only interleukin-4 but also other cytokines, especially in patients with CP.

  10. Functional cooperation of the dnaE and dnaN gene products in Escherichia coli.

    OpenAIRE

    Kuwabara, N; Uchida, H.

    1981-01-01

    A system was designed to isolate second-site intergenic suppressors of a thermosensitive mutation of the dnaE gene of Escherichia coli. The dnaE gene codes for the alpha subunit of DNA polymerase III [McHenry, C. S. & Crow, W. (1979) J. Biol. Chem. 254, 1748-1753]. One such suppressor, named sueA77, was finely mapped and found to be located at 82 min on the E. coli chromosome, between dnaA and recF, and within the dnaN gene [Sakakibara, Y. & Mizukami, T. (1980) Mol. Gen. Genet. 178, 541-553]....

  11. Production of transgenic pigs over-expressing the antiviral gene Mx1

    OpenAIRE

    2014-01-01

    The myxovirus resistance gene (Mx1) has a broad spectrum of antiviral activities. It is therefore an interesting candidate gene to improve disease resistance in farm animals. In this study, we report the use of somatic cell nuclear transfer (SCNT) to produce transgenic pigs over-expressing the Mx1 gene. These transgenic pigs express approximately 15–25 times more Mx1 mRNA than non-transgenic pigs, and the protein level of Mx1 was also markedly enhanced. We challenged fibroblast cells isolated...

  12. Identification, cloning, and characterization of the Ima operon, whose gene products are unique to Listeria monocytogenes.

    OpenAIRE

    1997-01-01

    The lmaA gene of Listeria monocytogenes encodes a protein capable of inducing delayed-type hypersensitivity reactions in L. monocytogenes-immune mice (S. Göhmann, M. Leimeister-Wachter, E. Schiltz, W. Goebel, and T. Chakraborty, M. Microbiol. 4:1091-1099, 1990). Here we show that it is the last gene of the lma operon, which now comprises four genes, lmaDCBA. Maxicell analysis of peptides encoded by the lma operon identified four polypeptides of 16.7, 16.4, 14.9, and 21 kDa which correspond to...

  13. Urea hydrolysis and suppressed production of thermostable direct hemolysin (TDH) by Vibrio parahaemolyticus associated with presence of TDH-related hemolysin genes.

    Science.gov (United States)

    Okitsu, T; Osawa, R; Pornruangwong, S; Yamai, S

    1997-05-01

    A total of 18 strains of V. parahaemolyticus isolated from patients of past food poisoning cases occurring in Kanagawa Prefecture, Japan, were assayed for presence of the thermostable direct hemolysin (TDH) gene and the TDH-related hemolysin (TRH) genes (trh 1 and trh 2) with specific reference to their ability to hydrolyze urea and TDH production. A polymerase chain reaction assay revealed that all urea-hydrolyzing strains (9 strains) carried either trh 1 gene or trh 2 gene. The strains carrying the trh genes as well as the tdh gene produced TDH less by a factor of 4 to 16 than those carrying only the tdh gene, suggesting the expression of the tdh gene was suppressed by the presence of trh gene through a mechanism yet to be defined.

  14. Distribution of the 3-hydroxyl-3-methylglutaryl coenzyme A reductase gene and isoprenoid production in marine-derived Actinobacteria.

    Science.gov (United States)

    Khan, Shams Tabrez; Izumikawa, Miho; Motohashi, Keiichiro; Mukai, Akira; Takagi, Motoki; Shin-Ya, Kazuo

    2010-03-01

    During the course of our screening program to isolate isoprenoids from marine Actinobacteria, 523 actinobacterial strains were isolated from 18 marine sponges, a tunicate, and two marine sediments. These strains belonged to 21 different genera, but most were members of Streptomyces, Nocardia, Rhodococcus, and Micromonospora. Some Actinobacteria have been reported to use the mevalonate pathway for the production of isoprenoids as secondary metabolites. Therefore, we investigated whether these strains possessed the 3-hydroxyl-3-methylglutaryl coenzyme A reductase (hmgr) gene, which indicates the presence of the mevalonate pathway. As a result, six strains belonging to the genera Streptomyces (SpC080624SC-11, SpA080624GE-02, and Sp080513GE-23), Nocardia (Sp080513SC-18), and Micromonospora (Se080624GE-07 and SpC080624GE-05) were found to possess the hmgr gene, and these genes were highly similar to hmgr genes in isoprenoid biosynthetic gene clusters. Among the six strains, the two strains SpC080624SC-11 and SpA080624GE-02 produced the novel isoprenoids, JBIR-46, -47, and -48, which consisted of phenazine chromophores, and Sp080513GE-23 produced a known isoprenoid, fumaquinone. Furthermore, these compounds showed cytotoxic activity against human acute myelogenous leukemia HL-60 cells.

  15. Association of a novel single nucleotide polymorphism in growth hormone receptor gene with production traits in Bali cattle

    Directory of Open Access Journals (Sweden)

    Maskur .

    2014-11-01

    Full Text Available The growth hormone (GH is the main regulator of postnatal growth and metabolism in mammals. The action of GH on target cells depends on the growth hormone receptor (GHR. This is mediated through induced transcription of other genes. GHR gene is one of the candidate genes employed in selection strategy using DNA markers (marker assisted selection. This study was designed to identify the novel single nucleotide polymorphisms (SNPs in exon 8 and intron 8 of GHR gene that may affect production traits in Bali cattle. A SNP was identified by the direct sequencing technique. Genotypes of the SNPs were identified using PCR-RFLP. The SNP was located in intron 8 of the GHR gene and was caused by an A/G transition. It was identified using the HpyCH4III restriction enzyme. Polymorphism of GHR/HpyCH4III has a significant influence on weaning weight and average daily gain, but not on birth weight of Bali cattle.

  16. The association of very low-density lipoprotein receptor (VLDLR haplotypes with egg production indicates VLDLR is a candidate gene for modulating egg production

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    ZhePeng Wang

    Full Text Available Abstract The very low-density lipoprotein receptor (VLDLR transports egg yolk precursors into oocytes. However, our knowledge of the distribution patterns of VLDLR variants among breeds and their relationship to egg production is still incomplete. In this study, eight single nucleotide polymorphisms (SNPs that account for 87% of all VLDLR variants were genotyped in Nick Chick (NC, n=91, Lohmann Brown (LohB, n=50 and Lueyang (LY, n=381 chickens, the latter being an Chinese indigenous breed. Egg production by NC and LY chickens was recorded from 17 to 50 weeks. Only four similar haplotypes were found in NC and LohB, of which two accounted for 100% of all NC haplotypes and 92.5% of LohB haplotypes. In contrast, there was considerable haplotypic diversity in LY. Comparison of egg production in LY showed that hens with NC-like haplotypes had a significantly higher production (p < 0.05 than those without the haplotypes. However, VLDLR expression was not significantly different between the haplotypes. These findings indicate a divergence in the distribution of VLDLR haplotypes between selected and non-selected breeds and suggest that the near fixation of VLDLR variants in NC and LohB is compatible with signature of selection. These data also support VLDLR as a candidate gene for modulating egg production.

  17. Evaluation of gene expression and alginate production in response to oxygen transfer in continuous culture of Azotobacter vinelandii.

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    Alvaro Díaz-Barrera

    Full Text Available Alginates are polysaccharides used as food additives and encapsulation agents in biotechnology, and their functional properties depend on its molecular weight. In this study, different steady-states in continuous cultures of A. vinelandii were established to determine the effect of the dilution rate (D and the agitation rate on alginate production and expression of genes involved in alginate polymerization and depolymerization. Both, the agitation and dilution rates, determined the partitioning of the carbon utilization from sucrose into alginate and CO2 under oxygen-limiting conditions. A low D (0.07 h(-1 and 500 rpm resulted in the highest carbon utilization into alginate (25%. Quantitative real-time polymerase chain reaction was used to determine the transcription level of six genes involved in alginate polymerization and depolymerization. In chemostat cultures at 0.07 h(-1, the gene expression was affected by changes in the agitation rate. By increasing the agitation rate from 400 to 600 rpm, the algE7 gene expression decreased tenfold, whereas alyA1, algL and alyA2 gene expression increased between 1.5 and 2.8 times under similar conditions evaluated. Chemostat at 0.07 h(-1 showed a highest alginate molecular weight (580 kDa at 500 rpm whereas similar molecular weights (480 kDa were obtained at 400 and 600 rpm. The highest molecular weight was not explained by changes in the expression of alg8 and alg44 (genes involved in alginate polymerization. Nonetheless, a different expression pattern observed for lyases could explain the highest alginate molecular weight obtained. Overall, the results suggest that the control of alginate molecular weight in A. vinelandii cells growing in continuous mode is determined by a balance between the gene expression of intracellular and extracellular lyases in response to oxygen availability. These findings better our understanding of the biosynthesis of bacterial alginate and help us progress toward obtain

  18. Evaluation of Gene Expression and Alginate Production in Response to Oxygen Transfer in Continuous Culture of Azotobacter vinelandii

    Science.gov (United States)

    Díaz-Barrera, Alvaro; Martínez, Fabiola; Guevara Pezoa, Felipe; Acevedo, Fernando

    2014-01-01

    Alginates are polysaccharides used as food additives and encapsulation agents in biotechnology, and their functional properties depend on its molecular weight. In this study, different steady-states in continuous cultures of A. vinelandii were established to determine the effect of the dilution rate (D) and the agitation rate on alginate production and expression of genes involved in alginate polymerization and depolymerization. Both, the agitation and dilution rates, determined the partitioning of the carbon utilization from sucrose into alginate and CO2 under oxygen-limiting conditions. A low D (0.07 h−1) and 500 rpm resulted in the highest carbon utilization into alginate (25%). Quantitative real-time polymerase chain reaction was used to determine the transcription level of six genes involved in alginate polymerization and depolymerization. In chemostat cultures at 0.07 h−1, the gene expression was affected by changes in the agitation rate. By increasing the agitation rate from 400 to 600 rpm, the algE7 gene expression decreased tenfold, whereas alyA1, algL and alyA2 gene expression increased between 1.5 and 2.8 times under similar conditions evaluated. Chemostat at 0.07 h−1 showed a highest alginate molecular weight (580 kDa) at 500 rpm whereas similar molecular weights (480 kDa) were obtained at 400 and 600 rpm. The highest molecular weight was not explained by changes in the expression of alg8 and alg44 (genes involved in alginate polymerization). Nonetheless, a different expression pattern observed for lyases could explain the highest alginate molecular weight obtained. Overall, the results suggest that the control of alginate molecular weight in A. vinelandii cells growing in continuous mode is determined by a balance between the gene expression of intracellular and extracellular lyases in response to oxygen availability. These findings better our understanding of the biosynthesis of bacterial alginate and help us progress toward obtain tailor

  19. Staphylococcus aureus Biofilm and Planktonic cultures differentially impact gene expression, mapk phosphorylation, and cytokine production in human keratinocytes

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    Olerud John E

    2011-06-01

    Full Text Available Abstract Background Many chronic diseases, such as non-healing wounds are characterized by prolonged inflammation and respond poorly to conventional treatment. Bacterial biofilms are a major impediment to wound healing. Persistent infection of the skin allows the formation of complex bacterial communities termed biofilm. Bacteria living in biofilms are phenotypically distinct from their planktonic counterparts and are orders of magnitude more resistant to antibiotics, host immune response, and environmental stress. Staphylococcus aureus is prevalent in cutaneous infections such as chronic wounds and is an important human pathogen. Results The impact of S. aureus soluble products in biofilm-conditioned medium (BCM or in planktonic-conditioned medium (PCM on human keratinocytes was investigated. Proteomic analysis of BCM and PCM revealed differential protein compositions with PCM containing several enzymes involved in glycolysis. Global gene expression of keratinocytes exposed to biofilm and planktonic S. aureus was analyzed after four hours of exposure. Gene ontology terms associated with responses to bacteria, inflammation, apoptosis, chemotaxis, and signal transduction were enriched in BCM treated keratinocytes. Several transcripts encoding cytokines were also upregulated by BCM after four hours. ELISA analysis of cytokines confirmed microarray results at four hours and revealed that after 24 hours of exposure, S. aureus biofilm induced sustained low level cytokine production compared to near exponential increases of cytokines in planktonic treated keratinocytes. The reduction in cytokines produced by keratinocytes exposed to biofilm was accompanied by suppressed phosphorylation of MAPKs. Chemical inhibition of MAPKs did not drastically reduce cytokine production in BCM-treated keratinocytes suggesting that the majority of cytokine production is mediated through MAPK-independent mechanisms. Conclusions Collectively the results indicate that S

  20. The ABNORMAL GAMETOPHYTES (AGM) gene product of Arabidopsis demonstrates a role in mitosis during gamete development.

    Science.gov (United States)

    Sorensen, Anna-Marie; Kroeber, Sandra; Saedler, Heinz

    2004-07-01

    Screening a T-DNA mutagenized population of Arabidopsis thaliana for reduced seed set and segregation distortion led to the isolation of the ABNORMAL GAMETOPHYTES (AGM) mutant. Homozygous plants were never recovered, but heterozygous plants showed mitotic defects during gametogenesis resulting in approximately 50% abortion of both the male and female gametes. Isolation of the genomic sequence flanking the co-segregating T-DNA element led to the identification of a gene located on chromosome 5, predicted to encode a transmembrane protein. BLAST homology searches identified two homologous proteins that are not redundant, as is clear from the existence of the agm mutant. Unexpectedly, expression studies using the beta-glucuronidase reporter gene suggest that AGM and its closest Arabidopsis homolog are mostly expressed in cells undergoing mitosis. Thus, AGM is not a gametophytic gene as originally speculated on the basis of segregation distortion, but rather classified as an essential gene crucial to the process of mitosis in plants.

  1. Production Data - Captive Broodstock Gene Rescue Program for Odd Year Class Elwha River Pink Salmon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Conduct captive brood stock gene rescue program for Elwha River odd-year class pink salmon. Information on the number of smolts received into the program is...

  2. Analysis of transfer genes and gene products within the traB-traC region of the Escherichia coli fertility factor, F.

    Science.gov (United States)

    Moore, D; Wu, J H; Kathir, P; Hamilton, C M; Ippen-Ihler, K

    1987-09-01

    A series of plasmids that carry overlapping segments of F DNA encoding the genes in the traB-traC interval was constructed, and a restriction enzyme map of the region was derived. Plasmids carrying deletions that had been introduced at an HpaI site within this interval were also isolated. The ability of these plasmids to complement transfer of F lac plasmids carrying mutations in traB, traV, and traW, and traC was analyzed. The protein products of the plasmids were labeled in UV-irradiated cells and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. These analyses showed that the product of traV is a polypeptide that migrates with an apparent molecular weight of 21,000. It was not detected when [35S]methionine was used to label plasmid products, but was readily detected in 14C-amino acid labeling experiments. A 21,500-dalton product appeared to stem from the region assigned to traP. A 9,000-dalton product was found to stem from a locus, named traR, that is located between traV and traC. No traW activity could be detected from the region of tra DNA examined. Our data also indicated that traC is located in a more promoter-proximal position than suggested on earlier maps. The plasmids constructed are expected to be useful in studies designed to identify the specific functions of the traB, -P, -V, -R, and -C products.

  3. Expression of carotenogenic genes and astaxanthin production in Xanthophyllomyces dendrorhous as a function of oxygen tension.

    Science.gov (United States)

    Wu, Wei; Lu, Mingbo; Yu, Longjiang

    2011-01-01

    This report gives an insight into the specific changes in the transcription of four key carotenogenic genes [encoding geranylgeranyl diphosphate synthase (crtE), phytoene desaturase (crtI), phytoene synthase lycopene cyclase (crtYB), and astaxanthin synthase (ast), respectively] in Xanthophyllomyces dendrorhous cultures, with regard to dissolved oxygen (DO) contents of 10%, 25%, and 40% air saturation, respectively. 25% DO proved to be the most beneficial for yeast growth, transcription of carotenogenic genes, and astaxanthin content.

  4. Characterization of Antibiotic Resistance Genes from Lactobacillus Isolated from Traditional Dairy Products.

    Science.gov (United States)

    Guo, Huiling; Pan, Lin; Li, Lina; Lu, Jie; Kwok, Laiyu; Menghe, Bilige; Zhang, Heping; Zhang, Wenyi

    2017-03-01

    Lactobacilli are widely used as starter cultures or probiotics in yoghurt, cheese, beer, wine, pickles, preserved food, and silage. They are generally recognized as safe (GRAS). However, recent studies have shown that some lactic acid bacteria (LAB) strains carry antibiotic resistance genes and are resistant to antibiotics. Some of them may even transfer their intrinsic antibiotic resistance genes to other LAB or pathogens via horizontal gene transfer, thus threatening human health. A total of 33 Lactobacillus strains was isolated from fermented milk collected from different areas of China. We analyzed (1) their levels of antibiotic resistance using a standardized dilution method, (2) their antibiotic resistance gene profiles by polymerase chain reaction (PCR) using gene-specific primers, and (3) the transferability of some of the detected resistance markers by a filter mating assay. All Lactobacillus strains were found to be resistant to vancomycin, but susceptible to gentamicin, linezolid, neomycin, erythromycin, and clindamycin. Their susceptibilities to tetracycline, kanamycin, ciprofloxacin, streptomycin, quinupristin/dalfopristin, trimethoprim, ampicillin, rifampicin, and chloramphenicol was different. Results from our PCR analysis revealed 19 vancomycin, 10 ciprofloxacin, and 1 tetracycline-resistant bacteria that carried the van(X), van(E), gyr(A), and tet(M) genes, respectively. Finally, no transferal of the monitored antibiotic resistance genes was observed in the filter mating assay. Taken together, our study generated the antibiotic resistance profiles of some milk-originated lactobacilli isolates and preliminarily assessed their risk of transferring antibiotic gene to other bacteria. The study may provide important data concerning the safe use of LAB. © 2017 Institute of Food Technologists®.

  5. Improving the measurement of semantic similarity between gene ontology terms and gene products: insights from an edge- and IC-based hybrid method.

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    Xiaomei Wu

    Full Text Available BACKGROUND: Explicit comparisons based on the semantic similarity of Gene Ontology terms provide a quantitative way to measure the functional similarity between gene products and are widely applied in large-scale genomic research via integration with other models. Previously, we presented an edge-based method, Relative Specificity Similarity (RSS, which takes the global position of relevant terms into account. However, edge-based semantic similarity metrics are sensitive to the intrinsic structure of GO and simply consider terms at the same level in the ontology to be equally specific nodes, revealing the weaknesses that could be complemented using information content (IC. RESULTS AND CONCLUSIONS: Here, we used the IC-based nodes to improve RSS and proposed a new method, Hybrid Relative Specificity Similarity (HRSS. HRSS outperformed other methods in distinguishing true protein-protein interactions from false. HRSS values were divided into four different levels of confidence for protein interactions. In addition, HRSS was statistically the best at obtaining the highest average functional similarity among human-mouse orthologs. Both HRSS and the groupwise measure, simGIC, are superior in correlation with sequence and Pfam similarities. Because different measures are best suited for different circumstances, we compared two pairwise strategies, the maximum and the best-match average, in the evaluation. The former was more effective at inferring physical protein-protein interactions, and the latter at estimating the functional conservation of orthologs and analyzing the CESSM datasets. In conclusion, HRSS can be applied to different biological problems by quantifying the functional similarity between gene products. The algorithm HRSS was implemented in the C programming language, which is freely available from http://cmb.bnu.edu.cn/hrss.

  6. Normal Collagen and Bone Production by Gene-targeted Human Osteogenesis Imperfecta iPSCs

    Science.gov (United States)

    Deyle, David R; Khan, Iram F; Ren, Gaoying; Wang, Pei-Rong; Kho, Jordan; Schwarze, Ulrike; Russell, David W

    2012-01-01

    Osteogenesis imperfecta (OI) is caused by dominant mutations in the type I collagen genes. In principle, the skeletal abnormalities of OI could be treated by transplantation of patient-specific, bone-forming cells that no longer express the mutant gene. Here, we develop this approach by isolating mesenchymal cells from OI patients, inactivating their mutant collagen genes by adeno-associated virus (AAV)-mediated gene targeting, and deriving induced pluripotent stem cells (iPSCs) that were expanded and differentiated into mesenchymal stem cells (iMSCs). Gene-targeted iMSCs produced normal collagen and formed bone in vivo, but were less senescent and proliferated more than bone-derived MSCs. To generate iPSCs that would be more appropriate for clinical use, the reprogramming and selectable marker transgenes were removed by Cre recombinase. These results demonstrate that the combination of gene targeting and iPSC derivation can be used to produce potentially therapeutic cells from patients with genetic disease. PMID:22031238

  7. Drosophila eggshell production: identification of new genes and coordination by Pxt.

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    Tina L Tootle

    Full Text Available Drosophila ovarian follicles complete development using a spatially and temporally controlled maturation process in which they resume meiosis and secrete a multi-layered, protective eggshell before undergoing arrest and/or ovulation. Microarray analysis revealed more than 150 genes that are expressed in a stage-specific manner during the last 24 hours of follicle development. These include all 30 previously known eggshell genes, as well as 19 new candidate chorion genes and 100 other genes likely to participate in maturation. Mutations in pxt, encoding a putative Drosophila cyclooxygenase, cause many transcripts to begin expression prematurely, and are associated with eggshell defects. Somatic activity of Pxt is required, as RNAi knockdown of pxt in the follicle cells recapitulates both the temporal expression and eggshell defects. One of the temporally regulated genes, cyp18a1, which encodes a cytochromome P450 protein mediating ecdysone turnover, is downregulated in pxt mutant follicles, and cyp18a1 mutation itself alters eggshell gene expression. These studies further define the molecular program of Drosophila follicle maturation and support the idea that it is coordinated by lipid and steroid hormonal signals.

  8. Inflammatory cytokines in vitro production are associated with Ala16Val superoxide dismutase gene polymorphism of peripheral blood mononuclear cells.

    Science.gov (United States)

    Montano, Marco Aurélio Echart; da Cruz, Ivana Beatrice Mânica; Duarte, Marta Maria Medeiros Frescura; Krewer, Cristina da Costa; da Rocha, Maria Izabel de Ugalde Marques; Mânica-Cattani, Maria Fernanda; Soares, Felix Alexandre Antunes; Rosa, Guilherme; Maris, Angélica Francesca; Battiston, Francielle Garghetti; Trott, Alexis; Lera, Juan Pablo Barrio

    2012-10-01

    Obesity is considered a chronic low-grade inflammatory state associated with a chronic oxidative stress caused by superoxide production (O(2)(-)). The superoxide dismutase manganese dependent (SOD2) catalyzes O(2)(-) in H(2)O(2) into mitochondria and is encoded by a single gene that presents a common polymorphism that results in the replacement of alanine (A) with a valine (V) in the 16 codon. This polymorphism has been implicated in a decreased efficiency of SOD2 transport into targeted mitochondria in V allele carriers. Previous studies described an association between VV genotype and metabolic diseases, including obesity and diabetes. However, the causal mechanisms to explain this association need to be more elucidated. We postulated that the polymorphism could influence the inflammatory response. To test our hypothesis, we evaluated the in vitro cytokines production by human peripheral blood mononuclear cells (PBMCs) carrier's different Ala16Val-SOD2 genotypes (IL-1, IL-6, IL-10, TNF-α, IFN-γ). Additionally, we evaluated if the culture medium glucose, enriched insulin, could influence the cytokine production. Higher levels of proinflammatory cytokines were observed in VV-PBMCs when compared to AA-PBMCs. However, the culture medium glucose and enriched insulin did not affect cytokine production. The results suggest that Ala16Val-SOD2 gene polymorphism could trigger the PBMCs proinflammatory cytokines level. However, discerning if a similar mechanism occurs in fat cells is an open question.

  9. Both decrease in ACL1 gene expression and increase in ICL1 gene expression in marine-derived yeast Yarrowia lipolytica expressing INU1 gene enhance citric acid production from inulin.

    Science.gov (United States)

    Liu, Xiao-Yan; Chi, Zhe; Liu, Guang-Lei; Madzak, Catherine; Chi, Zhen-Ming

    2013-02-01

    In this study, some of the ATP-citrate lyase genes (ACL1) were deleted and the copy number of the iso-citrate lyase gene (ICL1) was increased in the marine-derived yeast Yarrowia lipolytica SWJ-1b displaying the recombinant inulinase. It was found that lipid content and iso-citric acid in the transformant 30 obtained were greatly reduced and citric acid production was greatly enhanced. It was also found that the ACL1 gene expression and ATP-citrate lyase activity in the transformant 30 were declined and the ICL1 gene expression and iso-citrate lyase activity were promoted. During the 2-l fermentation, 84.0 g/l of citric acid and 1.8 g/l of iso-citric acid in the fermented medium were attained from 10.0 % of inulin by the transformant 30 within 214 h. The results showed that only 0.36 % of the residual reducing sugar and 1.0 % of the residual total sugar were left in the fermented medium, suggesting that 89.6 % of the total sugar was used for citric acid production and cell growth by the transformant 30.

  10. Genes essential for morphological development and antibiotic production in Streptomyces coelicolor are targets of BldD during vegetative growth.

    Science.gov (United States)

    den Hengst, Chris D; Tran, Ngat T; Bibb, Maureen J; Chandra, Govind; Leskiw, Brenda K; Buttner, Mark J

    2010-10-01

    BldD is a transcriptional regulator essential for morphological development and antibiotic production in Streptomyces coelicolor. Here we identify the BldD regulon by means of chromatin immunoprecipitation-microarray analysis (ChIP-chip). The BldD regulon encompasses ~167 transcriptional units, of which more than 20 are known to play important roles in development (e.g. bldA, bldC, bldH/adpA, bldM, bldN, ssgA, ssgB, ftsZ, whiB, whiG, smeA-ssfA) and/or secondary metabolism (e.g. nsdA, cvn9, bldA, bldC, leuA). Strikingly, 42 BldD target genes (~25% of the regulon) encode regulatory proteins, stressing the central, pleiotropic role of BldD. Almost all BldD binding sites identified by ChIP-chip are present in the promoters of the target genes. An exception is the tRNA gene bldA, where BldD binds within the region encoding the primary transcript, immediately downstream of the position corresponding to the processed, mature 3 end of the tRNA. Through gene overexpression, we identified a novel BldD target gene (cdgA) that influences differentiation and antibiotic production. cdgA encodes a GGDEF domain protein, implicating c-di-GMP in the regulation of Streptomyces development. Sequence analysis of the upstream regions of the complete regulon identified a 15 bp inverted repeat that functions as a high-affinity binding site for BldD, as was shown by electrophoretic mobility shift assays and DNase I footprinting analysis. High-scoring copies of the BldD binding site were found at relevant positions in the genomes of other bacteria containing a BldD homologue, suggesting the role of BldD is conserved in sporulating actinomycetes.

  11. A novel murrel Channa striatus mitochondrial manganese superoxide dismutase: gene silencing, SOD activity, superoxide anion production and expression.

    Science.gov (United States)

    Arockiaraj, Jesu; Palanisamy, Rajesh; Bhatt, Prasanth; Kumaresan, Venkatesh; Gnanam, Annie J; Pasupuleti, Mukesh; Kasi, Marimuthu

    2014-12-01

    We have reported the molecular characterization including gene silencing, superoxide activity, superoxide anion production, gene expression and molecular characterization of a mitochondrial manganese superoxide dismutase (mMnSOD) from striped murrel Channa striatus (named as CsmMnSOD). The CsmMnSOD polypeptide contains 225 amino acids with a molecular weight of 25 kDa and a theoretical isoelectric point of 8.3. In the N-terminal region, CsmMnSOD carries a mitochondrial targeting sequence and a superoxide dismutases (SOD) Fe domain (28-109), and in C-terminal region, it carries another SOD Fe domain (114-220). The CsmMnSOD protein sequence shared significant similarity with its homolog of MnSOD from rock bream Oplegnathus fasciatus (96%). The phylogenetic analysis showed that the CsmMnSOD fell in the clade of fish mMnSOD group. The monomeric structure of CsmMnSOD possesses 9 α-helices (52.4%), 3 β-sheets (8.8%) and 38.8% random coils. The highest gene expression was noticed in liver, and its expression was inducted with fungal (Aphanomyces invadans) and bacterial (Aeromonas hydrophila) infections. The gene silencing results show that the fish that received dsRNA exhibited significant (P superoxide anion production was determined by calculating the granular blood cell count during infection in murrel. It shows that the infection influenced the superoxide radical production which plays a major role in killing the pathogens. Overall, this study indicated the defense potentiality of CsmMnSOD; however, further research is necessary to explore its capability at protein level.

  12. GABA production and structure of gadB/gadC genes in Lactobacillus and Bifidobacterium strains from human microbiota.

    Science.gov (United States)

    Yunes, R A; Poluektova, E U; Dyachkova, M S; Klimina, K M; Kovtun, A S; Averina, O V; Orlova, V S; Danilenko, V N

    2016-12-01

    Gamma-amino butyric acid (GABA) is an active biogenic substance synthesized in plants, fungi, vertebrate animals and bacteria. Lactic acid bacteria are considered the main producers of GABA among bacteria. GABA-producing lactobacilli are isolated from food products such as cheese, yogurt, sourdough, etc. and are the source of bioactive properties assigned to those foods. The ability of human-derived lactobacilli and bifidobacteria to synthesize GABA remains poorly characterized. In this paper, we screened our collection of 135 human-derived Lactobacillus and Bifidobacterium strains for their ability to produce GABA from its precursor monosodium glutamate. Fifty eight strains were able to produce GABA. The most efficient GABA-producers were Bifidobacterium strains (up to 6 g/L). Time profiles of cell growth and GABA production as well as the influence of pyridoxal phosphate on GABA production were studied for L. plantarum 90sk, L. brevis 15f, B. adolescentis 150 and B. angulatum GT102. DNA of these strains was sequenced; the gadB and gadC genes were identified. The presence of these genes was analyzed in 14 metagenomes of healthy individuals. The genes were found in the following genera of bacteria: Bacteroidetes (Bacteroides, Parabacteroides, Alistipes, Odoribacter, Prevotella), Proteobacterium (Esherichia), Firmicutes (Enterococcus), Actinobacteria (Bifidobacterium). These data indicate that gad genes as well as the ability to produce GABA are widely distributed among lactobacilli and bifidobacteria (mainly in L. plantarum, L. brevis, B. adolescentis, B. angulatum, B. dentium) and other gut-derived bacterial species. Perhaps, GABA is involved in the interaction of gut microbiota with the macroorganism and the ability to synthesize GABA may be an important feature in the selection of bacterial strains - psychobiotics.

  13. Morphological changes induced by class III chitin synthase gene silencing could enhance penicillin production of Penicillium chrysogenum.

    Science.gov (United States)

    Liu, Hui; Zheng, Zhiming; Wang, Peng; Gong, Guohong; Wang, Li; Zhao, Genhai

    2013-04-01

    Chitin synthases catalyze the formation of β-(1,4)-glycosidic bonds between N-acetylglucosamine residues to form the unbranched polysaccharide chitin, which is the major component of cell walls in most filamentous fungi. Several studies have shown that chitin synthases are structurally and functionally divergent and play crucial roles in the growth and morphogenesis of the genus Aspergillus although little research on this topic has been done in Penicillium chrysogenum. We used BLAST to find the genes encoding chitin synthases in P. chrysogenum related to chitin synthase genes in Aspergillus nidulans. Three homologous sequences coding for a class III chitin synthase CHS4 and two hypothetical proteins in P. chrysogenum were found. The gene which product showed the highest identity and encoded the class III chitin synthase CHS4 was studied in detail. To investigate the role of CHS4 in P. chrysogenum morphogenesis, we developed an RNA interference system to silence the class III chitin synthase gene chs4. After transformation, mutants exhibited a slow growth rate and shorter and more branched hyphae, which were distinct from those of the original strain. The results also showed that the conidiation efficiency of all transformants was reduced sharply and indicated that chs4 is essential in conidia development. The morphologies of all transformants and the original strain in penicillin production were investigated by light microscopy, which showed that changes in chs4 expression led to a completely different morphology during fermentation and eventually caused distinct penicillin yields, especially in the transformants PcRNAi1-17 and PcRNAi2-1 where penicillin production rose by 27 % and 41 %, respectively.

  14. Enhancement of cytidine production by coexpression of gnd, zwf, and prs genes in recombinant Escherichia coli CYT15.

    Science.gov (United States)

    Fang, Haitian; Xie, Xixian; Xu, Qingyang; Zhang, Chenglin; Chen, Ning

    2013-02-01

    Cytidine is a precursor of several antiviral drugs. The pentose phosphate pathway (PPP) is primarily responsible for NADPH and 5-phospho-α-D-ribose 1-diphosphate as an important precursor of cytidine biosynthesis in Escherichia coli. To enhance cytidine production, we obtained the recombinant E. coli CYT15-gnd-prs-zwf that co-expressed the prs, zwf, and gnd genes encoding phosphoribosylpyrophosphate synthetase, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase (three key enzymes in PPP) respectively. In fermentation experiments, strain CYT15-gnd-prs-zwf produced 735 mg cytidine/l using glucose as substrate, which was approx. 128 % higher than the cytidine production by the parental strain (CYT15). Co-expression of zwf, gnd, and prs decreased growth (3.2 %) slightly and increased glucose uptake (72 %). This is the first study to report increased cytidine production by increasing metabolic flux through the PPP in E. coli.

  15. [Levels of thermostable direct hemolysin production by Vibrio parahaemolyticus strains carrying both tdh and trh genes].

    Science.gov (United States)

    Suzuki, N; Hashimoto, S; Ishibashi, M; Kim, Y B; Okuda, J; Nishibuchi, M

    1997-12-01

    One hundred and twenty-five strains of Vibrio parahaemolyticus carrying both the tdh and trh genes were selected from the strains isolated from the travelers with diarrhea by an hybridization test using polynucleotide probes. The levels of TDH produced by these strains and the association between the TDH levels and related characteristics in these strains were analyzed. The TDH level varied greatly from strain to strain, but none of the levels was as high as that of the typical Kanagawa phenomenon-positive strains. The strains were classified into "TDH producer" (18 strains), "Low-level TDH producer" (85 strains), and "No TDH producer" (22 strains) based on the results of a modified Elek test and the hemolysis assay on Wagatsuma agar. The highest TDH level achieved by the "TDH producer" was twofold lower than that of the Kanagawa phenomenon-positive strains as assayed by the RPLA method. All strains possessed the toxR gene. The trh1 and trh2 genes were detected in, respectively, 105 and 20 strains, and no correlation existed between the type of the trh gene and the levels of TDH produced. Considerable restriction fragment length polymorphism was observed with the tdh gene-bearing HindIII DNA fragment in different strains, but it was not related with the TDH level.

  16. Enhancing hydrogen production of Enterobacter aerogenes by heterologous expression of hydrogenase genes originated from Synechocystis sp.

    Science.gov (United States)

    Song, Wenlu; Cheng, Jun; Zhao, Jinfang; Zhang, Chuanxi; Zhou, Junhu; Cen, Kefa

    2016-09-01

    The hydrogenase genes (hoxEFUYH) of Synechocystis sp. PCC 6803 were cloned and heterologously expressed in Enterobacter aerogenes ATCC13408 for the first time in this study, and the hydrogen yield was significantly enhanced using the recombinant strain. A recombinant plasmid containing the gene in-frame with Glutathione-S-Transferase (GST) gene was transformed into E. aerogenes ATCC13408 to produce a GST-fusion protein. SDS-PAGE and western blot analysis confirm the successful expression of the hox genes. The hydrogenase activity of the recombinant strain is 237.6±9.3ml/(g-DW·h), which is 152% higher than the wild strain. The hydrogen yield of the recombinant strain is 298.3ml/g-glucose, which is 88% higher than the wild strain. During hydrogen fermentation, the recombinant strain produces more acetate and butyrate, but less ethanol. This is corresponding to the NADH metabolism in the cell due to the higher hydrogenase activity with the heterologous expression of hox genes.

  17. Production of Candida antarctica lipase B gene open reading frame using automated PCR gene assembly protocol on robotic workcell and expression in an ethanologenic yeast for use as resin-bound biocatalyst in biodiesel production.

    Science.gov (United States)

    Hughes, Stephen R; Moser, Bryan R; Harmsen, Amanda J; Bischoff, Kenneth M; Jones, Marjorie A; Pinkelman, Rebecca; Bang, Sookie S; Tasaki, Ken; Doll, Kenneth M; Qureshi, Nasib; Saha, Badal C; Liu, Siqing; Jackson, John S; Robinson, Samantha; Cotta, Michael C; Rich, Joseph O; Caimi, Paolo

    2011-02-01

    A synthetic Candida antarctica lipase B (CALB) gene open reading frame (ORF) for expression in yeast was constructed, and the lycotoxin-1 (Lyt-1) C3 variant gene ORF, potentially to improve the availability of the active enzyme at the surface of the yeast cell, was added in frame with the CALB ORF using an automated PCR assembly and DNA purification protocol on an integrated robotic workcell. Saccharomyces cerevisiae strains expressing CALB protein or CALB Lyt-1 fusion protein were first grown on 2% (w/v) glucose, producing 9.3 g/L ethanol during fermentation. The carbon source was switched to galactose for GAL1-driven expression, and the CALB and CALB Lyt-1 enzymes expressed were tested for fatty acid ethyl ester (biodiesel) production. The synthetic enzymes catalyzed the formation of fatty acid ethyl esters from ethanol and either corn or soybean oil. It was further demonstrated that a one-step-charging resin, specifically selected for binding to lipase, was capable of covalent attachment of the CALB Lyt-1 enzyme, and that the resin-bound enzyme catalyzed the production of biodiesel. High-level expression of lipase in an ethanologenic yeast strain has the potential to increase the profitability of an integrated biorefinery by combining bioethanol production with coproduction of a low-cost biocatalyst that converts corn oil to biodiesel.

  18. Detection and Diversity evaluation of tetracycline resistance genes in grassland-based production systems in Colombia, South America

    Directory of Open Access Journals (Sweden)

    Johanna eSantamaría

    2011-12-01

    Full Text Available Grassland-based production systems use approximately 26 percent of land surface on earth. However, there are no evaluations of these systems as a source of antibiotic pollution. This study was conducted to evaluate the presence, diversity, and distribution of tetracycline resistance genes in the grasslands of the Colombian Andes, where administration of antibiotics to animals is limited to treat disease and growth promoters are not included in animals’ diet. Animal (ruminal fluid and feces and environmental (soil and water samples were collected from six different dairy cattle farms and evaluated by PCR for the genes encoding ribosomal protection proteins (RPPs tet(M, tet(O, tetB(P, tet(Q tet(W, tet(S, tet(T, tet(A, and tetracycline efflux pumps tet(A, tet(B, tet(D, tet(H, tet(J, tet(Z, and tet(D. A wide distribution and high frequency for genes tet(W and tet(Q were found in both sample types. Other genes encoding RPPs ( tetB(P, tet(O, tet(M, tet(S and tet(T were detected at lower frequencies and more restricted distributions. Genes encoding efflux pumps were not common in this region, and only two of them, tet(B and tet(Z, were detected. DGGE-PCR followed by comparative sequence analysis of tet(W and tet(Q showed that the sequences detected in animals did not differ from those coming from soil and water, suggesting the transmission of tet genes from animal reservoirs to the environment. Additionally, there seems to be a differential flow of tet genes from one reservoir to the other because gene tet(O and tetB(P, detected in high frequencies in feces, were detected in low frequencies or not detected at all in the environment. Finally, the farms sampled in this study showed more than 50% similarity in relation to the tet genes detected and their frequencies. However, farms closer in space and under the influence of the same hydrographic network were significantly more similar to each other.

  19. Fosb gene products contribute to excitotoxic microglial activation by regulating the expression of complement C5a receptors in microglia.

    Science.gov (United States)

    Nomaru, Hiroko; Sakumi, Kunihiko; Katogi, Atsuhisa; Ohnishi, Yoshinori N; Kajitani, Kosuke; Tsuchimoto, Daisuke; Nestler, Eric J; Nakabeppu, Yusaku

    2014-08-01

    The Fosb gene encodes subunits of the activator protein-1 transcription factor complex. Two mature mRNAs, Fosb and ΔFosb, encoding full-length FOSB and ΔFOSB proteins respectively, are formed by alternative splicing of Fosb mRNA. Fosb products are expressed in several brain regions. Moreover, Fosb-null mice exhibit depressive-like behaviors and adult-onset spontaneous epilepsy, demonstrating important roles in neurological and psychiatric disorders. Study of Fosb products has focused almost exclusively on neurons; their function in glial cells remains to be explored. In this study, we found that microglia express equivalent levels of Fosb and ΔFosb mRNAs to hippocampal neurons and, using microarray analysis, we identified six microglial genes whose expression is dependent on Fosb products. Of these genes, we focused on C5ar1 and C5ar2, which encode receptors for complement C5a. In isolated Fosb-null microglia, chemotactic responsiveness toward the truncated form of C5a was significantly lower than that in wild-type cells. Fosb-null mice were significantly resistant to kainate-induced seizures compared with wild-type mice. C5ar1 mRNA levels and C5aR1 immunoreactivity were increased in wild-type hippocampus 24 hours after kainate administration; however, such induction was significantly reduced in Fosb-null hippocampus. Furthermore, microglial activation after kainate administration was significantly diminished in Fosb-null hippocampus, as shown by significant reductions in CD68 immunoreactivity, morphological change and reduced levels of Il6 and Tnf mRNAs, although no change in the number of Iba-1-positive cells was observed. These findings demonstrate that, under excitotoxicity, Fosb products contribute to a neuroinflammatory response in the hippocampus through regulation of microglial C5ar1 and C5ar2 expression.

  20. Genetic manipulation of longevity-related genes as a tool to regulate yeast life span and metabolite production during winemaking

    Directory of Open Access Journals (Sweden)

    Orozco Helena

    2013-01-01

    Full Text Available Abstract Background Yeast viability and vitality are essential for different industrial processes where the yeast Saccharomyces cerevisiae is used as a biotechnological tool. Therefore, the decline of yeast biological functions during aging may compromise their successful biotechnological use. Life span is controlled by a variety of molecular mechanisms, many of which are connected to stress tolerance and genomic stability, although the metabolic status of a cell has proven a main factor affecting its longevity. Acetic acid and ethanol accumulation shorten chronological life span (CLS, while glycerol extends it. Results Different age-related gene classes have been modified by deletion or overexpression to test their role in longevity and metabolism. Overexpression of histone deacetylase SIR2 extends CLS and reduces acetate production, while overexpression of SIR2 homolog HST3 shortens CLS, increases the ethanol level, and reduces acetic acid production. HST3 overexpression also enhances ethanol tolerance. Increasing tolerance to oxidative stress by superoxide dismutase SOD2 overexpression has only a moderate positive effect on CLS. CLS during grape juice fermentation has also been studied for mutants on several mRNA binding proteins that are regulators of gene expression at the posttranscriptional level; we found that NGR1 and UTH4 deletions decrease CLS, while PUF3 and PUB1 deletions increase it. Besides, the pub1Δ mutation increases glycerol production and blocks stress granule formation during grape juice fermentation. Surprisingly, factors relating to apoptosis, such as caspase Yca1 or apoptosis-inducing factor Aif1, play a positive role in yeast longevity during winemaking as their deletions shorten CLS. Conclusions Manipulation of regulators of gene expression at both transcriptional (i.e., sirtuins and posttranscriptional (i.e., mRNA binding protein Pub1 levels allows to modulate yeast life span during its biotechnological use. Due to

  1. Effect of casein genes - beta-LGB, DGAT1, GH, and LHR - on milk production and milk composition traits in crossbred Holsteins.

    Science.gov (United States)

    Molee, A; Poompramun, C; Mernkrathoke, P

    2015-03-30

    The objectives of this study were to determine the effects of a single gene and composite genotype of the casein gene family, including the beta-lactoglobulin gene (beta-LGB), acyl-CoA: diacylglycerol acyltransferase 1 gene (DGAT1), growth hormone gene (GH), and luteinizing hormone receptor gene (LHR) on milk yield, milk composition, the percentage of fat, protein, solids-not-fat, and total solid in crossbred Holsteins. A total of 231 crossbred Holstein cows were examined for the study. The genotype of the beta-casein gene was analyzed by allele-specific polymerase chain reaction, while the alpha-S1, alpha-S2, kappa-casein, DGAT1, beta-LGB, and GH genes were analyzed using a polymerase chain reaction-restriction fragment length polymorphism assay. The association between genes and milk yield and milk composition was analyzed. Three pairs of genes, for which significant associations were detected, were beta + kappa-casein, DGAT1 + beta-casein, and GH + beta-LGB. In the single-gene model, most loci are significantly associated with traits. A significant association between the composite genotype and the traits was detected in all composite genotypes. GH + beta-LGB appears to be the most suitable variants for improving milk production and percentage of milk protein. Overall, the effects of the composite genotype and single gene were different. A physical or functional relationship between genes is necessary for investigating gene markers.

  2. Regulation of lipid synthesis genes and milk fat production in human mammary epithelial cells during secretory activation.

    Science.gov (United States)

    Mohammad, Mahmoud A; Haymond, Morey W

    2013-09-15

    Expression of genes for lipid biosynthetic enzymes during initiation of lactation in humans is unknown. Our goal was to study mRNA expression of lipid metabolic enzymes in human mammary epithelial cell (MEC) in conjunction with the measurement of milk fatty acid (FA) composition during secretory activation. Gene expression from mRNA isolated from milk fat globule (MFG) and milk FA composition were measured from 6 h to 42 days postpartum in seven normal women. Over the first 96 h postpartum, daily milk fat output increased severalfold and mirrored expression of genes for all aspects of lipid metabolism and milk FA production, including lipolysis at the MEC membrane, FA uptake from blood, intracellular FA transport, de novo FA synthesis, FA and glycerol activation, FA elongation, FA desaturation, triglyceride synthesis, cholesterol synthesis, and lipid droplet formation. Expression of the gene for a key lipid synthesis regulator, sterol regulatory element-binding transcription factor 1 (SREBF1), increased 2.0-fold by 36 h and remained elevated over the study duration. Expression of genes for estrogen receptor 1, thyroid hormone-responsive protein, and insulin-induced 2 increased progressively to plateau by 96 h. In contrast, mRNA of peroxisome proliferator-activated receptor-γ decreased severalfold. With onset of lactation, increased de novo synthesis of FA was the most prominent change in milk FA composition and mirrored the expression of FA synthesis genes. In conclusion, milk lipid synthesis and secretion in humans is a complex process requiring the orchestration of a wide variety of pathways of which SREBF1 may play a primary role.

  3. VH Replacement Footprint Analyzer-I, a Java-Based Computer Program for Analyses of Immunoglobulin Heavy Chain Genes and Potential VH Replacement Products in Human and Mouse.

    Science.gov (United States)

    Huang, Lin; Lange, Miles D; Zhang, Zhixin

    2014-01-01

    VH replacement occurs through RAG-mediated secondary recombination between a rearranged VH gene and an upstream unrearranged VH gene. Due to the location of the cryptic recombination signal sequence (cRSS, TACTGTG) at the 3' end of VH gene coding region, a short stretch of nucleotides from the previous rearranged VH gene can be retained in the newly formed VH-DH junction as a "footprint" of VH replacement. Such footprints can be used as markers to identify Ig heavy chain (IgH) genes potentially generated through VH replacement. To explore the contribution of VH replacement products to the antibody repertoire, we developed a Java-based computer program, VH replacement footprint analyzer-I (VHRFA-I), to analyze published or newly obtained IgH genes from human or mouse. The VHRFA-1 program has multiple functional modules: it first uses service provided by the IMGT/V-QUEST program to assign potential VH, DH, and JH germline genes; then, it searches for VH replacement footprint motifs within the VH-DH junction (N1) regions of IgH gene sequences to identify potential VH replacement products; it can also analyze the frequencies of VH replacement products in correlation with publications, keywords, or VH, DH, and JH gene usages, and mutation status; it can further analyze the amino acid usages encoded by the identified VH replacement footprints. In summary, this program provides a useful computation tool for exploring the biological significance of VH replacement products in human and mouse.

  4. Characterization of biosynthetic gene cluster for the production of virginiamycin M, a streptogramin type A antibiotic, in Streptomyces virginiae.

    Science.gov (United States)

    Pulsawat, Nattika; Kitani, Shigeru; Nihira, Takuya

    2007-05-15

    Virginiamycin M (VM) of Streptomyces virginiae is a hybrid polyketide-peptide antibiotic with peptide antibiotic virginiamycin S (VS) as its synergistic counterpart. VM and VS belong to the Streptogramin family, which is characterized by strong synergistic antibacterial activity, and their water-soluble derivatives are a new therapeutic option for combating vancomycin-resistant Gram-positive bacteria. Here, the VM biosynthetic gene cluster was isolated from S. virginiae in the 62-kb region located in the vicinity of the regulatory island for virginiamycin production. Sequence analysis revealed that the region consists of 19 complete open reading frames (ORFs) and one C-terminally truncated ORF, encoding hybrid polyketide synthase (PKS)-nonribosomal peptide synthetase (NRPS), typical PKS, enzymes synthesizing precursors for VM, transporters for resistance, regulatory proteins, and auxiliary enzymes. The involvement of the cloned gene cluster in VM biosynthesis was confirmed by gene disruption of virA encoding a hybrid PKS-NRPS megasynthetase, which resulted in complete loss of VM production without any effect on VS production. To assemble the VM core structure, VirA, VirF, VirG, and VirH consisting, as a whole, of 24 domains in 8 PKS modules and 7 domains in 2 NRPS modules were predicted to act as an acyltransferase (AT)-less hybrid PKS-NRPS, whereas VirB, VirC, VirD, and VirE are likely to be essential for the incorporation of the methyl group into the VM framework by a HMG-CoA synthase-based reaction. Among several uncommon features of gene organization in the VM gene cluster, the lack of AT domain in every PKS module and the presence of a discrete AT encoded by virI are notable. AT-overexpression by an additional copy of virI driven by ermEp() resulted in 1.5-fold increase of VM production, suggesting that the amount of VirI is partly limiting VM biosynthesis.

  5. ASSOCIATIONS BETWEEN POLYMORPHISM OF GROWTH HORMONE GENE WITH MILK PRODUCTION, FAT AND PROTEIN CONTENT IN FRIESIAN HOLSTEIN CATTLE

    Directory of Open Access Journals (Sweden)

    T. Hartatik

    2016-02-01

    Full Text Available The aim of the research was to determine the associations between polymorphism of the bovine growth hormone (GH gene (Leu/Val and milk production of Friesian Holstein Cattle. A total of 62 cows which consist of two Friesian Holstein cattle groups (from New Zealand=19 heads and Australia=43 heads were used for the research. We performed the Polymerase Chain Reaction and followed by Restriction Fragment Length Polymorphism using AluI restriction enzyme. The genotype was observed base on the target gene GH 211 bp in the part of intron 4 and exon 5 of growth hormone gene. The frequencies of genotypes LL were found higher than genotype LV in both groups. Friesian Holstein cattle from New Zealand showed the genotype LL and LV as 84% and 16%, respectively. Friesian Holstein cattle from Australia show the genotype LL and LV as 79% and 21%, respectively. The association between Leu/Val polymorphism on milk production, fat and protein content in both groups did not show the significant effect. Base on two groups of the origin of cattle, the result showed the significant different on fat and protein content of milk. Fat and protein contents of milk were higher in breed of FH imported from Australia compared to those in breed of FH imported from New Zailand.

  6. Cloning, reassembling and integration of the entire nikkomycin biosynthetic gene cluster into Streptomyces ansochromogenes lead to an improved nikkomycin production

    Directory of Open Access Journals (Sweden)

    Yang Haihua

    2010-01-01

    Full Text Available Abstract Background Nikkomycins are a group of peptidyl nucleoside antibiotics produced by Streptomyces ansochromogenes. They are competitive inhibitors of chitin synthase and show potent fungicidal, insecticidal, and acaricidal activities. Nikkomycin X and Z are the main components produced by S. ansochromogenes. Generation of a high-producing strain is crucial to scale up nikkomycins production for further clinical trials. Results To increase the yields of nikkomycins, an additional copy of nikkomycin biosynthetic gene cluster (35 kb was introduced into nikkomycin producing strain, S. ansochromogenes 7100. The gene cluster was first reassembled into an integrative plasmid by Red/ET technology combining with classic cloning methods and then the resulting plasmid(pNIKwas introduced into S. ansochromogenes by conjugal transfer. Introduction of pNIK led to enhanced production of nikkomycins (880 mg L-1, 4 -fold nikkomycin X and 210 mg L-1, 1.8-fold nikkomycin Z in the resulting exconjugants comparing with the parent strain (220 mg L-1 nikkomycin X and 120 mg L-1 nikkomycin Z. The exconjugants are genetically stable in the absence of antibiotic resistance selection pressure. Conclusion A high nikkomycins producing strain (1100 mg L-1 nikkomycins was obtained by introduction of an extra nikkomycin biosynthetic gene cluster into the genome of S. ansochromogenes. The strategies presented here could be applicable to other bacteria to improve the yields of secondary metabolites.

  7. The wine yeast strain-dependent expression of genes implicated in sulfide production in response to nitrogen availability.

    Science.gov (United States)

    Mendes-Ferreira, Ana; Barbosa, Catarina; Jimenez-Marti, Elena; Del Olmo, Marcel Li; Mendes-Faia, Arlete

    2010-09-01

    Sulfur metabolism in S. cerevisiae is well established, but the mechanisms underlying the formation of sulfide remain obscure. Here we investigated by real time RT-PCR the dependence of expression levels of MET3, MET5/ECM17, MET10, MET16 and MET17 along with SSU1 on nitrogen availability in two wine yeast strains that produce divergent sulfide profiles. MET3 was the most highly expressed of the genes studied in strain PYCC4072, and SSU1 in strain UCD522. Strains behaved differently according to the sampling times, with UCD522 and PYCC4072 showing the highest expression levels at 120h and 72h, respectively. In the presence of 267mg assimilable N/l, the genes were more highly expressed in strain UCD522 than in PYCC4072. MET5/ECM17 and MET17 were only weakly expressed in both strains under any condition tested. MET10 and SSU1 in both strains, but MET16 only in PYCC4072, were consistently up-regulated when sulfide production was inhibited. This study illustrates that strain genotype could be important in determining enzyme activities and therefore the rate of sulfide liberation. This linkage, for some yeast strains, of sulfide production to expression levels of genes associated to sulfate assimilation and sulfur amino acid biosynthesis could be relevant for defining new strategies for genetic improvement of wine yeasts.

  8. Improved production of homo-D-lactic acid via xylose fermentation by introduction of xylose assimilation genes and redirection of the phosphoketolase pathway to the pentose phosphate pathway in L-Lactate dehydrogenase gene-deficient Lactobacillus plantarum.

    Science.gov (United States)

    Okano, Kenji; Yoshida, Shogo; Yamada, Ryosuke; Tanaka, Tsutomu; Ogino, Chiaki; Fukuda, Hideki; Kondo, Akihiko

    2009-12-01

    The production of optically pure d-lactic acid via xylose fermentation was achieved by using a Lactobacillus plantarum NCIMB 8826 strain whose l-lactate dehydrogenase gene was deficient and whose phosphoketolase genes were replaced with a heterologous transketolase gene. After 60 h of fermentation, 41.2 g/liter of d-lactic acid was produced from 50 g/liter of xylose.

  9. Targeted disruption of the mouse adenine phosphoribosyltransferase (aprt) gene and the production of APRT-deficient mice

    Energy Technology Data Exchange (ETDEWEB)

    Engle, S.J.; Chen, J.; Tischfield, J.A. [Indiana Univ., School of Medicine, Indianapolis, IN (United States)] [and others

    1994-09-01

    Adenine phosphoribosyltransferase (APRT: EC 2.4.2.7), a ubiquitously expressed purine salvage enzyme, catalyzes the synthesis of AMP and inorganic pyrophosphate from existing adenine and 5-phosphoribosyl-1-pyrophosphate. Deficiency of this enzyme in humans results in the accumulation of 2,8-dihydroxyadenine leading to crystalluria and nephrolithiasis. In order to facilitate our study of this rare, autosomal recessive disorder, we applied the advances in gene targeting technology and mouse embryonic stem (ES) cell culture to the production of APRT-deficient mice. A positive-negative targeting strategy was used. The tageting vector contain 5.6 kb of the mouse APRT gene, a neomycin resistance gene in exon 3 as a positive selection marker, and a HSV thymidine kinase gene at the 3{prime} end of the homology as a negative selection marker. The vector was introduced into D3 ES cells by electroporation and the cells were selected for G418 and ganciclovir (GANC) resistance. G418-GANC resistant clones were screened by Southern blot. One of several correctly targeted clones was expanded and used for blastocyst microinjection to produce chimeric mice. Chimeric animals were bred and agouti progeny heterozygous for the targeted allele were obtained. Heterozygous animals have been bred to produce APRT-deficient animals. Matings are currently underway to determine the phenotype of APRT/HPRT-deficient animals.

  10. High-Affinity Glucose Transport in Aspergillus nidulans Is Mediated by the Products of Two Related but Differentially Expressed Genes

    Science.gov (United States)

    Ventura, Luisa; González, Ramón; Ramón, Daniel; MacCabe, Andrew P.

    2014-01-01

    Independent systems of high and low affinity effect glucose uptake in the filamentous fungus Aspergillus nidulans. Low-affinity uptake is known to be mediated by the product of the mstE gene. In the current work two genes, mstA and mstC, have been identified that encode high-affinity glucose transporter proteins. These proteins' primary structures share over 90% similarity, indicating that the corresponding genes share a common origin. Whilst the function of the paralogous proteins is little changed, they differ notably in their patterns of expression. The mstC gene is expressed during the early phases of germination and is subject to CreA-mediated carbon catabolite repression whereas mstA is expressed as a culture tends toward carbon starvation. In addition, various pieces of genetic evidence strongly support allelism of mstC and the previously described locus sorA. Overall, our data define MstC/SorA as a high-affinity glucose transporter expressed in germinating conidia, and MstA as a high-affinity glucose transporter that operates in vegetative hyphae under conditions of carbon limitation. PMID:24751997

  11. Gene Sequence Based Clustering Assists in Dereplication of Pseudoalteromonas luteoviolacea Strains with Identical Inhibitory Activity and Antibiotic Production

    DEFF Research Database (Denmark)

    Vynne, Nikolaj Grønnegaard; Månsson, Maria; Gram, Lone

    2012-01-01

    Some microbial species are chemically homogenous, and the same secondary metabolites are found in all strains. In contrast, we previously found that five strains of P. luteoviolacea were closely related by 16S rRNA gene sequence but produced two different antibiotic profiles. The purpose of the p...... spent rediscovering known compounds, and this study indicates that phylogeny clustering of bioactive species has the potential to be a useful dereplication tool in biodiscovery efforts....... antibacterial profiles based on inhibition assays against Vibrio anguillarum and Staphylococcus aureus. To determine whether chemotype and inhibition profile are reflected by phylogenetic clustering we sequenced 16S rRNA, gyrB and recA genes. Clustering based on 16S rRNA gene sequences alone showed little...... correlation to chemotypes and inhibition profiles, while clustering based on concatenated 16S rRNA, gyrB, and recA gene sequences resulted in three clusters, two of which uniformly consisted of strains of identical chemotype and inhibition profile. A major time sink in natural products discovery is the effort...

  12. High-affinity glucose transport in Aspergillus nidulans is mediated by the products of two related but differentially expressed genes.

    Directory of Open Access Journals (Sweden)

    Josep V Forment

    Full Text Available Independent systems of high and low affinity effect glucose uptake in the filamentous fungus Aspergillus nidulans. Low-affinity uptake is known to be mediated by the product of the mstE gene. In the current work two genes, mstA and mstC, have been identified that encode high-affinity glucose transporter proteins. These proteins' primary structures share over 90% similarity, indicating that the corresponding genes share a common origin. Whilst the function of the paralogous proteins is little changed, they differ notably in their patterns of expression. The mstC gene is expressed during the early phases of germination and is subject to CreA-mediated carbon catabolite repression whereas mstA is expressed as a culture tends toward carbon starvation. In addition, various pieces of genetic evidence strongly support allelism of mstC and the previously described locus sorA. Overall, our data define MstC/SorA as a high-affinity glucose transporter expressed in germinating conidia, and MstA as a high-affinity glucose transporter that operates in vegetative hyphae under conditions of carbon limitation.

  13. Gene disruption technologies have the potential to transform stored product insect pest control

    Science.gov (United States)

    Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, ...

  14. Functional Reconstitution of a Fungal Natural Product Gene Cluster by Advanced Genome Editing

    DEFF Research Database (Denmark)

    Weber, Jakob; Valiante, Vito; Nødvig, Christina Spuur

    2017-01-01

    Filamentous fungi produce varieties of natural products even in a strain dependent manner. However, the genetic basis of chemical speciation between strains is still widely unknown. One example is trypacidin, a natural product of the opportunistic human pathogen Aspergillus fumigatus, which...... for advanced molecular genetic studies in filamentous fungi, exploiting selectable markers separated from the edited locus....

  15. Enhanced Production of Polysaccharide Through the Overexpression of Homologous Uridine Diphosphate Glucose Pyrophosphorylase Gene in a Submerged Culture of Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Higher Basidiomycetes).

    Science.gov (United States)

    Ji, Sen-Lin; Liu, Rui; Ren, Meng-Fei; Li, Huan-Jun; Xu, Jun-Wei

    2015-01-01

    This study aimed to improve polysaccharide production by engineering the biosynthetic pathway in Ganoderma lucidum through the overexpression of the homologous UDP glucose pyrophosphorylase (UGP) gene. The effects of UGP gene overexpression on intracellular polysaccharide (IPS) content, extracellular polysaccharide (EPS) production, and transcription levels of 3 genes encoding the enzymes involved in polysaccharide biosynthesis, including phosphoglucomutase (PGM), UGP, and α-1,3-glucan synthase (GLS), were investigated. The maximum IPS content and EPS production in G. lucidum overexpressing the UGP gene were 24.32 mg/100 mg dry weight and 1.66 g/L, respectively, which were higher by 42% and 36% than those of the wild-type strain. The transcription levels of PGM, UGP, and GLS were up-regulated by 1.6, 2.6, and 2.4-fold, respectively, in the engineered strain, suggesting that increased polysaccharide biosynthesis may result from a higher expression of those genes.

  16. Citric acid production and citrate synthase genes in distinct strains of ...

    African Journals Online (AJOL)

    SAM

    2014-05-28

    May 28, 2014 ... 3Departamento de Biologia, UEFS Campus UniversitárioCEP 44.036-900 Caixa Postal 252-294 Feira de ... cycle enzymes, the utilization of molecular techniques ... identification of the gene, which codifies for the citrate.

  17. Reprogramming Hansenula polymorpha for penicillin production : expression of the Penicillium chrysogenum pcl gene

    NARCIS (Netherlands)

    Gidijala, Loknath; van der Klei, Ida J.; Veenhuis, Marten; Kiel, Jan A. K. W.

    2007-01-01

    We aim to introduce the penicillin biosynthetic pathway into the methylotrophic yeast Hansenula polymorpha. To allow simultaneous expression of the multiple genes of the penicillin biosynthetic pathway, additional markers were required. To this end, we constructed a novel host-vector system based on

  18. Production of transgenic chickens expressing a tetracycline-inducible GFP gene.

    Science.gov (United States)

    Kwon, Mo Sun; Koo, Bon Chul; Roh, Ji Yeol; Kim, Minjee; Kim, Jin-Hoi; Kim, Teoan

    2011-07-15

    There is much interest in using farm animals as 'bioreactors' to produce large quantities of biopharmaceuticals. However, uncontrolled constitutive expression of foreign genes have been known to cause serious physiological disturbances in transgenic animals. The objective of this study was to test the feasibility of the controllable expression of an exogenous gene in the chicken. A retrovirus vector was designed to express GFP (green fluorescent protein) and rtTA (reverse tetracycline-controlled transactivator) under the control of the tetracycline-inducible promoter and the PGK (phosphoglycerate kinase) promoter, respectively. G0 founder chickens were produced by infecting the blastoderm of freshly laid eggs with concentrated retrovirus vector. Feeding the chickens obtained with doxycycline, a tetracycline derivative, resulted in emission of green body color under fluorescent light, and no apparent significant physiological dysfunctions. Successful germline transmission of the exogenous gene was also confirmed. Expression of the GFP gene reverted to the pre-induction levels when doxycycline was removed from the diet. The results showed that a tetracycline-inducible expression system in transgenic animals might be a promising solution to minimize physiological disturbances caused by the transgene. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Chlamydia trachomatis contains a protein similar to the Legionella pneumophila mip gene product

    DEFF Research Database (Denmark)

    Lundemose, AG; Birkelund, Svend; Fey, SJ;

    1991-01-01

    A 27kDa Chlamydia trachomatis L2 protein was characterized by the use of monoclonal antibodies and by two-dimensional gel electrophoresis. The protein was shown to be located in the membrane of reticulate bodies as well as elementary bodies. Its synthesis could be detected from 10 hours post-infe...... potentiator (mip) gene of Legionella pneumophila....

  20. Identification of the Pr1 gene product completes the anthocyanin biosynthesis pathway of maize

    Science.gov (United States)

    In maize, mutations in the pr1 locus lead to the accumulation of pelargonidin (red) rather than cyanidin (purple) pigments in aleurone cells where the anthocyanin biosynthetic pathway is active. We characterized pr1 mutation and isolated a putative F3'H encoding gene (Zmf3'h1), and showed by segrega...

  1. Pollen and seed mediated gene flow in commercial alfalfa seed production fields

    Science.gov (United States)

    The potential for gene flow has been widely recognized since alfalfa is pollinated by bees. The Western US is a major exporter of alfalfa seed and hay and the organic dairy industry is one of the fastest growing agricultural sectors. Because of this, many alfalfa producers are impacted by market sen...

  2. Structures and comparative characterization of biosynthetic gene clusters for cyanosporasides, enediyne-derived natural products from marine actinomycetes.

    Science.gov (United States)

    Lane, Amy L; Nam, Sang-Jip; Fukuda, Takashi; Yamanaka, Kazuya; Kauffman, Christopher A; Jensen, Paul R; Fenical, William; Moore, Bradley S

    2013-03-20

    Cyanosporasides are marine bacterial natural products containing a chlorinated cyclopenta[a]indene core of suspected enediyne polyketide biosynthetic origin. Herein, we report the isolation and characterization of novel cyanosporasides C-F (3-6) from the marine actinomycetes Salinispora pacifica CNS-143 and Streptomyces sp. CNT-179, highlighted by the unprecedented C-2' N-acetylcysteamine functionalized hexose group of 6. Cloning, sequencing, and mutagenesis of homologous ~50 kb cyanosporaside biosynthetic gene clusters from both bacteria afforded the first genetic evidence supporting cyanosporaside's enediyne, and thereby p-benzyne biradical, biosynthetic origin and revealed the molecular basis for nitrile and glycosyl functionalization. This study provides new opportunities for bioengineering of enediyne derivatives and expands the structural diversity afforded by enediyne gene clusters.

  3. Expression of a cyanobacterial {del}{sup 6}-desaturase gene results in {gamma}-linolenic acid production in transgenic plants

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.S.; Thomas, T.L. [Texas A & M Univ., College Station, TX (United States)

    1996-05-01

    Gamma-linolenic acid (GLA), a nutritionally important fatty acid in human and animal diets, is not produced in oil seed crops. Many oil seed plants, however, produce significant quantities of linoleic acid, a fatty acid that could be converted to GLA by the enzyme {del}{sup 6}-desaturase if it were present. As a first step to producing GLA in oil seed crops, we have cloned a cyanobacterial {del}{sup 6}-desaturase gene. Expression of this gene in transgenic tobacco resulted in GLA accumulation. Octadecatetraenoic acid, a highly unsaturated, industrially important fatty acid, was also found in transgenic tobacco plants expressing the cyanobacterial {del}{sup 6}-desaturase. This is the first example of engineering the production of `novel` polyunsaturated fatty acids in transgenic plants. 28 refs., 4 figs., 1 tab.

  4. Associations between novel polymorphisms at the 5'-UTR region of the prolactin gene and egg production and quality in chickens.

    Science.gov (United States)

    Bhattacharya, T K; Chatterjee, R N; Sharma, R P; Niranjan, M; Rajkumar, U

    2011-03-01

    The objective was to characterize polymorphisms at the 5'-UTR region of the prolactin gene, and determine their association with egg production and egg quality traits in White Leghorn chickens. The study was conducted on four strains of White Leghorn chickens, namely IWH, IWI, IWK, and layer control. Overall, there were three alleles (designated A, B, and C) and five genotypes, with genotypic frequencies of 0.09, 0.75, 0.07, 0.02, and 0.07 for AA, AB, AC, BB, and BC, respectively. There were significant differences among genotypes for egg production up to 52 and 64 wk of age, with maximal egg yields for genotypes AA and AC (144.5 ± 5.06 and 143.2 ± 4.67 eggs, respectively). Furthermore, there were significant differences among genotypes for egg quality traits, including egg weight and Haugh unit at 40 wk of age, Haugh unit at 52 wk, and yolk color index and Haugh unit at 64 wk. Birds with AA or AC genotypes had the best egg quality traits. On the contrary, these genotypes had the lowest prolactin expression, whereas this expression was highest in birds with the BB genotype. In conclusion, polymorphisms at the 5'-UTR of prolactin gene were significantly associated with egg production and egg quality traits in White Leghorn chickens.

  5. Enhancement of poly-3-hydroxybutyrate production in Synechocystis sp. PCC 6803 by overexpression of its native biosynthetic genes.

    Science.gov (United States)

    Khetkorn, Wanthanee; Incharoensakdi, Aran; Lindblad, Peter; Jantaro, Saowarath

    2016-08-01

    Synechocystis sp. PCC 6803 strains overexpressing pha genes were constructed and characterized for poly-3-hydroxybutyrate (PHB) production. These pha overexpressing strains showed slightly reduced growth rates. Under N-deprived condition, the strains overexpressing (OE) phaAB, phaEC and phaABEC showed significantly higher PHB contents than the wild type. The maximum PHB content, a 2.6-fold increase producing 26% PHB (dcw), was observed in OE phaAB cells grown for 9days in N-deprived medium. Under this condition, these OE phaAB cells increased PHB production to 35% PHB (dcw) upon addition of 0.4% (w/v) acetate. Higher PHB granules in OE phaAB cells were clearly visualized by both Nile red staining and TEM imaging. All OE strains under N-deficient condition had increased glgX transcript levels. Overall results demonstrate an enhanced PHB production in Synechocystis cells overexpressing pha genes, particularly phaA and phaB, when grown in N-deprived medium containing 0.4% (w/v) acetate.

  6. Genetic polymorphisms of leptin and leptin receptor genes in relation with production and reproduction traits in cattle.

    Science.gov (United States)

    Trakovická, Anna; Moravčíková, Nina; Kasarda, Radovan

    2013-01-01

    Leptin and leptin receptor genes are considered as production traits markers in dairy or beef cattle. The aim of this study was to verify the associations of polymorphisms in bovine LEP and LEPR genes with production and reproduction traits in Slovak Spotted and Pinzgau cows. Long-life production was evaluated: milk, protein, and fat yield and reproduction traits: age at first calving, calving interval, days open, and insemination interval. In total, 296 blood samples of Slovak Spotted and 85 hair roots samples of Pinzgau cows were analyzed. In order to detect LEP/Sau3AI (BTA 4, inron 2) and LEPR/T945M (BTA 3, exon 20) genotypes PCR-RFLP method was used. In Slovak Spotted and Pinzgau cows allele frequencies were 0.838/0.162 and 0.694/0.306 for A and B LEP variants, and 0.954/0.046 and 0.912/0.088 for C and T LEPR variants, respectively. For testing the associations between SNPs LEP/Sau3AI and LEPR/T945M and evaluated traits, the General Linear Model procedure in SAS Software was used. Statistical analysis showed that SNP LEP/Sau3AI significantly affected milk, protein and fat yield (Pcattle breeds.

  7. Sodium houttuyfonate affects production of N-acyl homoserine lactone and quorum sensing-regulated genes expression in Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Daqiang eWu

    2014-11-01

    Full Text Available Quorum sensing (QS is a means of cell-to-cell communication that uses diffusible signaling molecules that are sensed by the population to determine population density, thus allowing co-ordinate gene regulation in response to population density. In Pseudomonas aeruginosa, production of the QS signaling molecule, N-acyl homoserine lactone (AHL, co-ordinates expression of key factors of pathogenesis, including biofilm formation and toxin secretion. It is predicted that the inhibition of AHL sensing would provide an effective clinical treatment to reduce the expression of virulence factors and increase the effectiveness of antimicrobial agents. We previously demonstrated that sodium houttuyfonate (SH, commonly used in traditional Chinese medicine to treat infectious diseases, can effectively inhibit QS-regulated processes, including biofilm formation. Here, using a model system, we demonstrate that SH causes the dose-dependent inhibition of AHL production, through down-regulation of the AHL biosynthesis gene, lasI. Addition of SH also resulted in down-regulation of expression of the AHL sensor and transcriptional regulator, LasR, and inhibited the production of the QS-regulated virulence factors, pyocyanin and LasA. These results suggest that the antimicrobial activity of SH may be due to its ability to disrupt QS in P. aeruginosa.

  8. Use of aiiA gene amplification for AHL-lactonase production from endophytic bacterium Enterobacter species.

    Science.gov (United States)

    Rajesh, P S; Rai, V Ravishankar

    2015-01-01

    AHL-lactonase has gained renewed interest due to biotechnological applications such as antiquorum sensing, antibiofilm strategies, biofouling, etc. In our study, the production of AHL-lactonase from endophytic bacteria Enterobacter aerogenes VT66 was optimized by response surface methodology (RSM) using central composite design (CCD) for four different cultural conditions. The relative activity of AHL-lactonase was correlated with amplification of aiiA homologous gene amplification with respect to cultural conditions. Statistical analysis by ANOVA of the quadratic regression model showed that the RSM model constructed is highly significant, as indicated by F-test with a low probability value (p(model) < 0.0001) and high regression coefficient (0.9997) as well as lower coefficient of variation (1.86%) indicate that suitability of variable parameters. The quadratic regression model of AHL-lactonase production in terms of relative activity was built and the optimal cultural conditions for maximum enzyme production were determined as 32.5 °C temperature, pH 7.0, 350 μM of substrate concentration and 33 h of incubation time. The enhanced AHL-lactonase yielded 1.33 fold increases in relative activity and it positively correlated with the amplification of aiiA gene.

  9. Evaluation of bovine chemerin (RARRES2 gene variation on beef cattle production traits

    Directory of Open Access Journals (Sweden)

    Amanda K Lindholm-Perry

    2012-03-01

    Full Text Available A previous study in cattle based on >48,000 markers identified markers on chromosome 4 near the chemerin gene associated with average daily feed intake (ADFI in steers (P<0.008. Chemerin is an adipokine associated with obesity and metabolic syndrome in humans, representing a strong candidate gene potentially underlying the observed association. To evaluate whether the bovine chemerin gene is involved in feed intake, 16 markers within and around the gene were tested for association in the same resource population. Eleven were nominally significant for ADFI (P<0.05 and two were significant after Bonferroni correction. Two and five SNP in this region were nominally significant for the related traits of average daily gain (ADG and residual feed intake (RFI, respectively. All markers were evaluated for effects on meat quality and carcass phenotypes. Many of the markers associated with ADFI were associated with hot carcass weight (HCW, adjusted fat thickness (AFT, and marbling (P<0.05. Marker alleles that were associated with lower ADFI were also associated with lower HCW, AFT, and marbling. Markers associated with ADFI were genotyped in a validation population of steers representing 14 breeds to determine predictive merit across populations. No consistent relationships for ADFI were detected. To determine whether cattle feed intake or growth phenotypes might be related to chemerin transcript abundance, the expression of chemerin was evaluated in adipose of 114 heifers that were siblings of the steers in the discovery population. Relative chemerin transcript abundance was not correlated with ADFI, ADG, or RFI, but associations with body condition score and yearling weight were observed. We conclude that variation in the chemerin gene may underlie observed association in the resource population, but that additional research is required to determine if this variation is widespread among breeds and to develop robust markers with predictive merit across

  10. The piggyBac-Based Gene Delivery System Can Confer Successful Production of Cloned Porcine Blastocysts with Multigene Constructs

    Directory of Open Access Journals (Sweden)

    Masahiro Sato

    2016-08-01

    Full Text Available The introduction of multigene constructs into single cells is important for improving the performance of domestic animals, as well as understanding basic biological processes. In particular, multigene constructs allow the engineering and integration of multiple genes related to xenotransplantation into the porcine genome. The piggyBac (PB transposon system allows multiple genes to be stably integrated into target genomes through a single transfection event. However, to our knowledge, no attempt to introduce multiple genes into a porcine genome has been made using this system. In this study, we simultaneously introduced seven transposons into a single porcine embryonic fibroblast (PEF. PEFs were transfected with seven transposons containing genes for five drug resistance proteins and two (red and green fluorescent proteins, together with a PB transposase expression vector, pTrans (experimental group. The above seven transposons (without pTrans were transfected concomitantly (control group. Selection of these transfected cells in the presence of multiple selection drugs resulted in the survival of several clones derived from the experimental group, but not from the control. PCR analysis demonstrated that approximately 90% (12/13 tested of the surviving clones possessed all of the introduced transposons. Splinkerette PCR demonstrated that the transposons were inserted through the TTAA target sites of PB. Somatic cell nuclear transfer (SCNT using a PEF clone with multigene constructs demonstrated successful production of cloned blastocysts expressing both red and green fluorescence. These results indicate the feasibility of this PB-mediated method for simultaneous transfer of multigene constructs into the porcine cell genome, which is useful for production of cloned transgenic pigs expressing multiple transgenes.

  11. De Novo Transcriptomic Analysis of an Oleaginous Microalga: Pathway Description and Gene Discovery for Production of Next-Generation Biofuels

    Science.gov (United States)

    Wan, LingLin; Han, Juan; Sang, Min; Li, AiFen; Wu, Hong; Yin, ShunJi; Zhang, ChengWu

    2012-01-01

    Background Eustigmatos cf. polyphem is a yellow-green unicellular soil microalga belonging to the eustimatophyte with high biomass and considerable production of triacylglycerols (TAGs) for biofuels, which is thus referred to as an oleaginous microalga. The paucity of microalgae genome sequences, however, limits development of gene-based biofuel feedstock optimization studies. Here we describe the sequencing and de novo transcriptome assembly for a non-model microalgae species, E. cf. polyphem, and identify pathways and genes of importance related to biofuel production. Results We performed the de novo assembly of E. cf. polyphem transcriptome using Illumina paired-end sequencing technology. In a single run, we produced 29,199,432 sequencing reads corresponding to 2.33 Gb total nucleotides. These reads were assembled into 75,632 unigenes with a mean size of 503 bp and an N50 of 663 bp, ranging from 100 bp to >3,000 bp. Assembled unigenes were subjected to BLAST similarity searches and annotated with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology identifiers. These analyses identified the majority of carbohydrate, fatty acids, TAG and carotenoids biosynthesis and catabolism pathways in E. cf. polyphem. Conclusions Our data provides the construction of metabolic pathways involved in the biosynthesis and catabolism of carbohydrate, fatty acids, TAG and carotenoids in E. cf. polyphem and provides a foundation for the molecular genetics and functional genomics required to direct metabolic engineering efforts that seek to enhance the quantity and character of microalgae-based biofuel feedstock. PMID:22536352

  12. The piggyBac-Based Gene Delivery System Can Confer Successful Production of Cloned Porcine Blastocysts with Multigene Constructs

    Science.gov (United States)

    Sato, Masahiro; Maeda, Kosuke; Koriyama, Miyu; Inada, Emi; Saitoh, Issei; Miura, Hiromi; Ohtsuka, Masato; Nakamura, Shingo; Sakurai, Takayuki; Watanabe, Satoshi; Miyoshi, Kazuchika

    2016-01-01

    The introduction of multigene constructs into single cells is important for improving the performance of domestic animals, as well as understanding basic biological processes. In particular, multigene constructs allow the engineering and integration of multiple genes related to xenotransplantation into the porcine genome. The piggyBac (PB) transposon system allows multiple genes to be stably integrated into target genomes through a single transfection event. However, to our knowledge, no attempt to introduce multiple genes into a porcine genome has been made using this system. In this study, we simultaneously introduced seven transposons into a single porcine embryonic fibroblast (PEF). PEFs were transfected with seven transposons containing genes for five drug resistance proteins and two (red and green) fluorescent proteins, together with a PB transposase expression vector, pTrans (experimental group). The above seven transposons (without pTrans) were transfected concomitantly (control group). Selection of these transfected cells in the presence of multiple selection drugs resulted in the survival of several clones derived from the experimental group, but not from the control. PCR analysis demonstrated that approximately 90% (12/13 tested) of the surviving clones possessed all of the introduced transposons. Splinkerette PCR demonstrated that the transposons were inserted through the TTAA target sites of PB. Somatic cell nuclear transfer (SCNT) using a PEF clone with multigene constructs demonstrated successful production of cloned blastocysts expressing both red and green fluorescence. These results indicate the feasibility of this PB-mediated method for simultaneous transfer of multigene constructs into the porcine cell genome, which is useful for production of cloned transgenic pigs expressing multiple transgenes. PMID:27589724

  13. De novo transcriptomic analysis of an oleaginous microalga: pathway description and gene discovery for production of next-generation biofuels.

    Directory of Open Access Journals (Sweden)

    LingLin Wan

    Full Text Available BACKGROUND: Eustigmatos cf. polyphem is a yellow-green unicellular soil microalga belonging to the eustimatophyte with high biomass and considerable production of triacylglycerols (TAGs for biofuels, which is thus referred to as an oleaginous microalga. The paucity of microalgae genome sequences, however, limits development of gene-based biofuel feedstock optimization studies. Here we describe the sequencing and de novo transcriptome assembly for a non-model microalgae species, E. cf. polyphem, and identify pathways and genes of importance related to biofuel production. RESULTS: We performed the de novo assembly of E. cf. polyphem transcriptome using Illumina paired-end sequencing technology. In a single run, we produced 29,199,432 sequencing reads corresponding to 2.33 Gb total nucleotides. These reads were assembled into 75,632 unigenes with a mean size of 503 bp and an N50 of 663 bp, ranging from 100 bp to >3,000 bp. Assembled unigenes were subjected to BLAST similarity searches and annotated with Gene Ontology (GO and Kyoto Encyclopedia of Genes and Genomes (KEGG orthology identifiers. These analyses identified the majority of carbohydrate, fatty acids, TAG and carotenoids biosynthesis and catabolism pathways in E. cf. polyphem. CONCLUSIONS: Our data provides the construction of metabolic pathways involved in the biosynthesis and catabolism of carbohydrate, fatty acids, TAG and carotenoids in E. cf. polyphem and provides a foundation for the molecular genetics and functional genomics required to direct metabolic engineering efforts that seek to enhance the quantity and character of microalgae-based biofuel feedstock.

  14. Accumulation of VH Replacement Products in IgH Genes Derived from Autoimmune Diseases and Anti-Viral Responses in Human.

    Science.gov (United States)

    Lange, Miles D; Huang, Lin; Yu, Yangsheng; Li, Song; Liao, Hongyan; Zemlin, Michael; Su, Kaihong; Zhang, Zhixin

    2014-01-01

    VH replacement refers to RAG-mediated secondary recombination of the IgH genes, which renews almost the entire VH gene coding region but retains a short stretch of nucleotides as a VH replacement footprint at the newly generated VH-DH junction. To explore the biological significance of VH replacement to the antibody repertoire, we developed a Java-based VH replacement footprint analyzer program and analyzed the distribution of VH replacement products in 61,851 human IgH gene sequences downloaded from the NCBI database. The initial assignment of the VH, DH, and JH gene segments provided a comprehensive view of the human IgH repertoire. To our interest, the overall frequency of VH replacement products is 12.1%; the frequencies of VH replacement products in IgH genes using different VH germline genes vary significantly. Importantly, the frequencies of VH replacement products are significantly elevated in IgH genes derived from different autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, and allergic rhinitis, and in IgH genes encoding various autoantibodies or anti-viral antibodies. The identified VH replacement footprints preferentially encoded charged amino acids to elongate IgH CDR3 regions, which may contribute to their autoreactivities or anti-viral functions. Analyses of the mutation status of the identified VH replacement products suggested that they had been actively involved in immune responses. These results provide a global view of the distribution of VH replacement products in human IgH genes, especially in IgH genes derived from autoimmune diseases and anti-viral immune responses.

  15. Expression of POX2 gene and disruption of POX3 genes in the industrial Yarrowia lipolytica on the γ-decalactone production.

    Science.gov (United States)

    Guo, Yanqiong; Song, Huanlu; Wang, Zhaoyue; Ding, Yongzhi

    2012-04-20

    The yeast Yarrowia lipolytica growing on methyl ricinoleate can produce γ-decalactone, the worthy aroma compound, which can exhibit fruity and creamy sensorial notes, and recognized internationally as a safe food additive. Unfortunately, the yield is poor because of lactone degradation by enzyme Aox3 (POX3 gene encoded), which was responsible for continuation of oxidation after C(10) level and lactone reconsumption. In this paper, we chose the industrial Y. lipolytica (CGMCC accession number 2.1405), which is the diploid strain as the starting strain and constructed the recombinant strain Tp-12 by targeting the POX3 locus of the wild type, one copy of POX3 was deleted by CRF1+POX2 insertion. The other recombinant strain Tpp-11, which was a null mutant possessing multiple copies of POX2 and disrupted POX3 genes on two chromosomes, was constructed by inserting XPR2+hpt into the other copy of POX3 of Tp-12. The growth ability of the recombinants was changed after genetic modification in the fermentation medium. The production of γ-decalactone was increased, resulting from blocking β-oxidation at the C(10) Aox level and POX2 overexpression. The recombinant strain Tpp-11 was stable. Because there was no reconsumption of γ-decalactone, the mutant strain could be grown in continuous fermentation of methyl ricinoleate to produce γ-decalactone.

  16. Postnatal development of protein gene product 9.5 and calcitonin gene-related peptide immunoreactive nerve fibres in rat temporomandibular joint disc.

    Science.gov (United States)

    Ueki, N; Tanaka, E; Watanabe, M; Wakida, K; Takahashi, O; Uchida, T; Tanne, K

    2003-02-01

    Protein gene product 9.5 (PGP 9.5), an immunohistochemical marker of whole nerve fibres, and calcitonin gene-related peptide (CGRP), a marker of thin nerve fibres, were used to elucidate the postnatal development of nerve fibres in rat temporomandibular joint (TMJ) disc. At birth, PGP 9.5-immunoreactive nerve fibres exhibited running towards the central area of the disc, invading by approximately 95 m from the disc attachment. The nerve fibres existing inside the disc became longer during postnatal development. The number of nerve fibres in the disc increased in a progressive manner up to 40 days after birth. CGRP-immunoreactive nerve fibres also presented changes essentially similar to those of PGP 9.5-immunoreactive nerve fibres. However, the proportion of CGRP-immunoreactive nerve fibres to PGP 9.5-immunoreactive ones was approximately 80%, and remained constant up to 40 days after birth. In conclusion, the distribution and the number of nerve fibres are variable during postnatal development, although the ratio of thin nerve fibres remains invariable. It is emphasized that these changes of innervation in the TMJ are associated with the development of masticatory function.

  17. Deletion of the Saccharomyces cerevisiae ARO8 gene, encoding an aromatic amino acid transaminase, enhances phenylethanol production from glucose.

    Science.gov (United States)

    Romagnoli, Gabriele; Knijnenburg, Theo A; Liti, Gianni; Louis, Edward J; Pronk, Jack T; Daran, Jean-Marc

    2015-01-01

    Phenylethanol has a characteristic rose-like aroma that makes it a popular ingredient in foods, beverages and cosmetics. Microbial production of phenylethanol currently relies on whole-cell bioconversion of phenylalanine with yeasts that harbour an Ehrlich pathway for phenylalanine catabolism. Complete biosynthesis of phenylethanol from a cheap carbon source, such as glucose, provides an economically attractive alternative for phenylalanine bioconversion. In this study, synthetic genetic array (SGA) screening was applied to identify genes involved in regulation of phenylethanol synthesis in Saccharomyces cerevisiae. The screen focused on transcriptional regulation of ARO10, which encodes the major decarboxylase involved in conversion of phenylpyruvate to phenylethanol. A deletion in ARO8, which encodes an aromatic amino acid transaminase, was found to underlie the transcriptional upregulation of ARO10 during growth, with ammonium sulphate as the sole nitrogen source. Physiological characterization revealed that the aro8Δ mutation led to substantial changes in the absolute and relative intracellular concentrations of amino acids. Moreover, deletion of ARO8 led to de novo production of phenylethanol during growth on a glucose synthetic medium with ammonium as the sole nitrogen source. The aro8Δ mutation also stimulated phenylethanol production when combined with other, previously documented, mutations that deregulate aromatic amino acid biosynthesis in S. cerevisiae. The resulting engineered S. cerevisiae strain produced >3 mm phenylethanol from glucose during growth on a simple synthetic medium. The strong impact of a transaminase deletion on intracellular amino acid concentrations opens new possibilities for yeast-based production of amino acid-derived products.

  18. Wild-type Escherichia coli producing microcins B17, D93, J25, and L; cloning of genes for microcin L production and immunity.

    Science.gov (United States)

    Sablé, S; Duarte, M; Bravo, D; Lanneluc, I; Pons, A M; Cottenceau, G; Moreno, F

    2003-05-01

    For the first time, an Escherichia coli strain producing four microcins (Mcc), B17, D93, J25, and L, and showing immunity to Mcc V was isolated and characterized. Each of the gene clusters encoding the production of Mcc B17, D93, and L was cloned separately. The gene cluster for Mcc L was cloned within a 13.5-kb HindIII-SalI fragment, which includes the Mcc V immunity gene, cvi.

  19. Construction of efficient Streptococcus zooepidemicus strains for hyaluoronic acid production based on identification of key genes involved in sucrose metabolism.

    Science.gov (United States)

    Zhang, Xuzhen; Wang, Man; Li, Tuanjie; Fu, Lixia; Cao, Wei; Liu, Hao

    2016-12-01

    Biosynthesis of polysaccharide hyaluoronic acid (HA) by Streptococcus zooepidemicus is a carbon-intensive process. The carbon flux and factor(s) restricting HA yield were not well understood. Here, we investigated the function of genes involved in sucrose metabolism and identified targets limiting HA yield, which were exploited to construct efficient S. zooepidemicus strains for HA production. The sucrose uptake was addressed by deletion of scrA and scrB, which encodes sucrose-PTS permease and sucrose-6-phosphate hydrolase, respectively. We found that scrB was essential for the growth of S. zooepidemicus and HA biosynthesis, and accumulation of sucrose-6-phosphate was toxic. ΔscrB could not grow in THY-sucrose medium, while ΔscrA and ΔscrAΔscrB showed negligible growth defects. Overexpression of scrA significantly reduced biomass and HA production, while overexpression of scrB resulted in 26% increase of biomass and 30% increase of HA yield. We revealed that fructose-6-phosphate for HA biosynthesis mainly originates from glucose-6-phosphate. Deletion of scrK, a gene encoding hexokinase, led to 11% reduction of biomass and 12% decrease of HA yield, while deletion of hasE, a gene encoding phosphoglucoisomerase, resulted in the abolishment of HA biosynthesis and a significantly slow growth. We found that HA biosynthesis could be improved by directing carbon flux to fructose-6-phosphate. Deletion of fruA encoding the EII of fructose-PTS and fruK encoding phosphofructokinase showed no apparent effect on cell growth, but resulted in 22 and 27% increase of HA yield, respectively. Finally, a strain with 55% increase of HA was constructed by overexpression of scrB in ΔfruK. These results provide a solid foundation for further metabolic engineering of S. zooepidemicus for highly efficient HA production.

  20. Design and construction of a first-generation high-throughput integrated molecular biology platform for production of optimized synthetic genes and improved industrial strains

    Science.gov (United States)

    The molecular biological techniques for plasmid-based assembly and cloning of synthetic assembled gene open reading frames are essential for elucidating the function of the proteins encoded by the genes. These techniques involve the production of full-length cDNA libraries as a source of plasmid-bas...

  1. The presence of c-erbB-2 gene product-related protein in culture medium conditioned by breast cancer cell line SK-BR-3

    Energy Technology Data Exchange (ETDEWEB)

    Alper, O.; Yamaguchi, K.; Hitomi, J.; Honda, S.; Matsushima, T.; Abe, K. (National Cancer Center Research Institute, Tokyo (Japan))

    1990-12-01

    The Mr 185,000 glycoprotein encoded by human c-erbB-2/neu/HER2 gene, termed c-erbB-2 gene product, shows a close structural similarity with epidermal growth factor receptor and is now regarded to be a growth factor receptor for an as yet unidentified ligand. Abundant c-erbB-2 mRNA was demonstrated by Northern blot studies in the human breast cancer cell line SK-BR-3. Cellular radiolabeling experiments followed by immunoprecipitation with three different anti-c-erbB-2 gene product antibodies, recognizing extracellular domain, kinase domain, and carboxyl-terminal portion, respectively, demonstrated the production of a large amount of c-erbB-2 gene product which had the capacity to be phosphorylated. Immunization of mice with concentrated culture medium conditioned by SK-BR-3 cells always generated antibodies against c-erbB-2 gene product, demonstrating that this culture medium contained substance(s) immunologically indistinguishable from c-erbB-2 gene product. This observation was supported by the successful development of a monoclonal antibody against c-erbB-2 gene product, GFD-OA-p185-1, by immunizing mice with this culture medium. The biochemical nature of the substance(s) present in the culture medium was further characterized. When the culture medium conditioned by (35S)cysteine-labeled SK-BR-3 cells was immunoprecipitated by three different anti-c-erbB-2 gene product antibodies, only the antibody recognizing extracellular domain precipitated the (35S)-labeled protein with a molecular weight of 110,000, namely p110. The newly developed monoclonal antibody also immunoprecipitated this protein.

  2. Crystallization and preliminary X-ray analysis of ocr, the product of gene 0.3 of bacteriophage T7.

    Science.gov (United States)

    Sturrock, S S; Dryden, D T; Atanasiu, C; Dornan, J; Bruce, S; Cronshaw, A; Taylor, P; Walkinshaw, M D

    2001-11-01

    Ocr, the product of gene 0.3 of bacteriophage T7, prevents the action of restriction endonucleases of the host bacteria. The amino-acid sequence of ocr has less than 20% similarity to any protein of known three-dimensional structure. Ocr has been crystallized in a number of different crystal forms and X-ray data for the seleno-L-methionine-substituted form has been collected to a resolution of 1.8 A. The presence of caesium was found to be required for good crystal growth. Anomalous X-ray data was used to identify possible positions for Se and Cs atoms in the unit cell.

  3. Immediate-early gene product ICP22 inhibits the trans-transcription activating function of P53-mdm-2

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    As a product of HSVI immediate-early gene, ICP22 is capable of interacting with various cellular tran-scriptive and regulatory molecules during viral infection so as to impact the normal cellular molecular mechanism. ICP22 expressed in transfected cells can push the cells’ entering into S phase with binding to mdm-1 promoter region and impact its trans-transcription activating effect by P53. Consequently, the MDM-2 binds to P53, and the degradation effects by the ubiquitous pathway are decreased, improving indirectly the P53 levels in cells and making the cells progress into the S phase.

  4. Immediate-early gene product ICP22 inhibits the trans-transcription activating function of P53-mdm-2

    Institute of Scientific and Technical Information of China (English)

    GUO HongXiong; CUN Wei; LIU LongDing; WANG LiChun; ZHAO HongLing; DONG ChengHong; LI QiHan

    2007-01-01

    As a product of HSVI immediate-early gene, ICP22 is capable of interacting with various cellular transcriptive and regulatory molecules during viral infection so as to impact the normal cellular molecular mechanism. ICP22 expressed in transfected cells can push the cells' entering into S phase with binding to mdm-1 promoter region and impact its trans-transcription activating effect by P53. Consequently, the MDM-2 binds to P53, and the degradation effects by the ubiquitous pathway are decreased, improving indirectly the P53 levels in cells and making the cells progress into the S phase.

  5. Overexpression and rapid purification of the orfE/rph gene product, RNase PH of Escherichia coli

    DEFF Research Database (Denmark)

    Jensen, Kaj Frank; Andersen, J T; Poulsen, Peter

    1992-01-01

    acid residue protein which was recently identified as the phosphorolytic ribonuclease, RNase PH, that removes nucleotides from the 3' ends of tRNA precursors. In this paper we report the construction of a plasmid, which overexpresses the orfE and pyrE gene products substantially, as well...... as the purification of the OrfE protein by ammonium sulfate precipitation and chromatography on phosphocellulose. The highly purified protein catalyzes the phosphorolytic cleavage of poly(A) at a rate of 1.6 mumol/min/mg and the formation of CDP from tRNA-CCA-Cn and orthophosphate at a rate equal to 0.14 mumol...

  6. Prevalence, Virulence Genes, Antimicrobial Susceptibility, and Genetic Diversity of Staphylococcus aureus from Retail Aquatic Products in China.

    Science.gov (United States)

    Rong, Dongli; Wu, Qingping; Xu, Mingfang; Zhang, Jumei; Yu, Shubo

    2017-01-01

    Staphylococcus aureus is an important food-borne opportunistic pathogen that frequently causes severe blood and tissue infections or even fatal illnesses. Although S. aureus has been extensively studied in livestock and poultry foods in China, limited information has been reported in aquatic products. Accordingly, in this study, we aimed to characterize S. aureus in aquatic products purchased from retail markets in China. In total, 320 aquatic food samples were collected from 32 provincial capitals in China. The results showed that 119 samples (37.2%, 119/320) were positive for S. aureus by both qualitative and quantitative analyses. The contamination levels of 78.2% of samples ranged from 0.3 to 10 MPN/g, and six samples exceeded 110 MPN/g. A total of 119 S. aureus isolates from positive samples were selected to evaluate virulence factors, antibiotic resistance, and molecular characteristics. All S. aureus isolates were evaluated for the presence of 11 virulence genes by multiplex polymerase chain reaction, and α-hemolysin (hlα, 84.9%), fibronectin-binding protein A (fnbA, 79.0%), S. aureus enterotoxin E (see, 53.8%), and Panton-Valentine leucocidin (pvl, 50.4%) were identified as the major genes. These genes formed 56 different profiles, with the major profile identified as pvl-hlα-fnbA (28.6%). The antimicrobial susceptibility of all isolates was analyzed through the disk diffusion method, and the results showed high resistance to β-lactams, macrolides and tetracyclines, but susceptibility to linezolid and vancomycin. In addition, 26 sequence types (STs) were obtained via multilocus sequence typing, including seven novel STs, among which ST1 (20.2%), ST15 (18.5%), and ST188 (13.4%) were the most common STs. All the isolates were mecC negative, but nine isolates carrying mecA were evaluated by staphylococcal cassette chromosome mec (SCCmec) typing, all of which were SCCmecIII or SCCmecIV types. Isolates of SCCmecIII showed a high prevalence and were multidrug

  7. Large-scale production and evaluation of marker-free indica rice IR64 expressing phytoferritin genes.

    Science.gov (United States)

    Oliva, Norman; Chadha-Mohanty, Prabhjit; Poletti, Susanna; Abrigo, Editha; Atienza, Genelou; Torrizo, Lina; Garcia, Ruby; Dueñas, Conrado; Poncio, Mar Aristeo; Balindong, Jeanette; Manzanilla, Marina; Montecillo, Florencia; Zaidem, Maricris; Barry, Gerard; Hervé, Philippe; Shou, Huxia; Slamet-Loedin, Inez H

    2014-01-01

    Biofortification of rice (Oryza sativa L.) using a transgenic approach to increase the amount of iron in the grain is proposed as a low-cost, reliable, and sustainable solution to help developing countries combat anemia. In this study, we generated and evaluated a large number of rice or soybean ferritin over-accumulators in rice mega-variety IR64, including marker-free events, by introducing soybean or rice ferritin genes into the endosperm for product development. Accumulation of the protein was confirmed by ELISA, in situ immunological detection, and Western blotting. As much as a 37- and 19-fold increase in the expression of ferritin gene in single and co-transformed plants, respectively, and a 3.4-fold increase in Fe content in the grain over the IR64 wild type was achieved using this approach. Agronomic characteristics of a total of 1,860 progenies from 58 IR64 single independent transgenic events and 768 progenies from 27 marker-free transgenic events were evaluated and most trait characteristics did not show a penalty. Grain quality evaluation of high-Fe IR64 transgenic events showed quality similar to that of the wild-type IR64. To understand the effect of transgenes on iron homeostasis, transcript analysis was conducted on a subset of genes involved in iron uptake and loading. Gene expression of the exogenous ferritin gene in grain correlates with protein accumulation and iron concentration. The expression of NAS2 and NAS3 metal transporters increased during the grain milky stage.

  8. The targeted inactivation of TRβ gene in thyroid follicular cells suggests a new mechanism of regulation of thyroid hormone production.

    Science.gov (United States)

    Selmi-Ruby, Samia; Bouazza, Lamia; Obregon, Maria-Jesus; Conscience, Aude; Flamant, Frédéric; Samarut, Jacques; Borson-Chazot, Françoise; Rousset, Bernard

    2014-02-01

    Thyroid epithelial cells, or thyrocytes, express functional thyroid hormone receptors but no precise role has yet been assigned to either TRα or TRβ in the thyroid gland. In this study, we analyzed the impact of inactivating the TRβ gene in the thyroid of mice. First, we generated a mouse line named Thyr-Cre, expressing the Cre recombinase under the control of the thyroglobulin gene promoter, which led to a complete recombination of floxed genes in thyrocytes. Thyr-Cre mice were then crossed with TRβ floxed mice (TRβ(flox/flox)) to obtain a thyrocyte-selective deletion of TRβ. Thyr-TRβ(-/-) mice were characterized by a decrease in the size and functional activity of the thyroid gland. These alterations were associated with a decrease in plasma TSH concentration. Surprisingly, Thyr-TRβ(-/-) displayed elevated serum T(4) and rT(3) concentrations with no significant change in serum T(3) levels. Their intrathyroidal free T(4) and rT(3) contents were also elevated, whereas the ratio of serum T(4) to thyroid free T(4) was decreased by comparison with wild-type littermates. Also, within the thyroid, deiodinases D1 and D2 were reduced as well as the expression levels of genes encoding monocarboxylate transporters (Mct8 and Mct10). Such a decrease in intrathyroidal deiodination of T(4) and in the expression of genes encoding thyroid hormone transporters may contribute to the primary overproduction of T(4) observed in Thyr-TRβ(-/-) mice. In conclusion, these data show that the control of thyroid hormone production involves not only TRβ-dependent mechanisms acting at the level of hypothalamus and pituitary but also TRβ-dependent mechanisms acting at the thyroid level.

  9. Downstream processing and chromatography based analytical methods for production of vaccines, gene therapy vectors, and bacteriophages

    Science.gov (United States)

    Kramberger, Petra; Urbas, Lidija; Štrancar, Aleš

    2015-01-01

    Downstream processing of nanoplexes (viruses, virus-like particles, bacteriophages) is characterized by complexity of the starting material, number of purification methods to choose from, regulations that are setting the frame for the final product and analytical methods for upstream and downstream monitoring. This review gives an overview on the nanoplex downstream challenges and chromatography based analytical methods for efficient monitoring of the nanoplex production. PMID:25751122

  10. Downstream processing and chromatography based analytical methods for production of vaccines, gene therapy vectors, and bacteriophages.

    Science.gov (United States)

    Kramberger, Petra; Urbas, Lidija; Štrancar, Aleš

    2015-01-01

    Downstream processing of nanoplexes (viruses, virus-like particles, bacteriophages) is characterized by complexity of the starting material, number of purification methods to choose from, regulations that are setting the frame for the final product and analytical methods for upstream and downstream monitoring. This review gives an overview on the nanoplex downstream challenges and chromatography based analytical methods for efficient monitoring of the nanoplex production.

  11. Results on single cell PCR for Huntington's gene and WAVE product analysis for preimplantation genetic diagnosis.

    Science.gov (United States)

    Drury, K C; Liu, M C; Lilleberg, S; Kipersztok, S; Williams, R S

    2001-10-22

    Triple repeat base pair amplification is the basis for a number of prevalent genetic diseases such as Huntington's, Fragile X, Myotonic Dystrophy and others. We have chosen to investigate the use of PCR to amplify a portion of the Huntington's gene in single cells in order to develop a clinical test system for preimplantation genetic diagnosis (PGD). Amplification of CAG triple repeat sequences poses difficulties due to resistance of GC melting for amplification. Special PCR modifications are necessary to carry out the amplification of GC rich areas found in most triple base pair expansions. We have used a modified polymerase chain reaction (PCR) protocol to amplify the expanded repeat sequence of the Huntington's gene with satisfactory efficiency. Detection of the amplified expanded CAG repeats is shown to be possible using both agarose gel electrophoresis and high definition denaturing high pressure liquid (DHPLC) chromatography. The incidence of allele dropout (ADO) is documented.

  12. Global analysis of biosynthetic gene clusters reveals vast potential of secondary metabolite production in Penicillium species

    DEFF Research Database (Denmark)

    Nielsen, Jens Christian; Grijseels, Sietske; Prigent, Sylvain

    2017-01-01

    Filamentous fungi produce a wide range of bioactive compounds with important pharmaceutical applications, such as antibiotic penicillins and cholesterol-lowering statins. However, less attention has been paid to fungal secondary metabolites compared to those from bacteria. In this study, we...... sequenced the genomes of 9 Penicillium species and, together with 15 published genomes, we investigated the secondary metabolism of Penicillium and identified an immense, unexploited potential for producing secondary metabolites by this genus. A total of 1,317 putative biosynthetic gene clusters (BGCs) were...... identified, and polyketide synthase and non-ribosomal peptide synthetase based BGCs were grouped into gene cluster families and mapped to known pathways. The grouping of BGCs allowed us to study the evolutionary trajectory of pathways based on 6-methylsalicylic acid (6-MSA) synthases. Finally, we cross...

  13. Engineering of avermectin biosynthetic genes to improve production of ivermectin in Streptomyces avermitilis.

    Science.gov (United States)

    Li, Meng; Chen, Zhi; Lin, Xiuping; Zhang, Xuan; Song, Yuan; Wen, Ying; Li, Jilun

    2008-10-15

    Two new recombinants of avermectin polyketide synthases were constructed by domain and module swapping in Streptomyces avermitilis 73-12. However, only the strain, S. avermitilis OI-31, formed by domain substitution could produce ivermectin. Analysis of the ivermectin synthesized gene cluster showed that decreased amount of aveC transcripts was one of the factors causing low yield of ivermectin. Overexpression of aveC could improve ivermectin yield.

  14. The HP0256 gene product is involved in motility and cell envelope architecture of Helicobacter pylori

    LENUS (Irish Health Repository)

    Douillard, Francois P

    2010-04-08

    Abstract Background Helicobacter pylori is the causative agent for gastritis, and peptic and duodenal ulcers. The bacterium displays 5-6 polar sheathed flagella that are essential for colonisation and persistence in the gastric mucosa. The biochemistry and genetics of flagellar biogenesis in H. pylori has not been fully elucidated. Bioinformatics analysis suggested that the gene HP0256, annotated as hypothetical, was a FliJ homologue. In Salmonella, FliJ is a chaperone escort protein for FlgN and FliT, two proteins that themselves display chaperone activity for components of the hook, the rod and the filament. Results Ablation of the HP0256 gene in H. pylori significantly reduced motility. However, flagellin and hook protein synthesis was not affected in the HP0256 mutant. Transmission electron transmission microscopy revealed that the HP0256 mutant cells displayed a normal flagellum configuration, suggesting that HP0256 was not essential for assembly and polar localisation of the flagella in the cell. Interestingly, whole genome microarrays of an HP0256 mutant revealed transcriptional changes in a number of genes associated with the flagellar regulon and the cell envelope, such as outer membrane proteins and adhesins. Consistent with the array data, lack of the HP0256 gene significantly reduced adhesion and the inflammatory response in host cells. Conclusions We conclude that HP0256 is not a functional counterpart of FliJ in H. pylori. However, it is required for full motility and it is involved, possibly indirectly, in expression of outer membrane proteins and adhesins involved in pathogenesis and adhesion.

  15. Whole-Genome Microarray and Gene Deletion Studies Reveal Regulation of the Polyhydroxyalkanoate Production Cycle by the Stringent Response in Ralstonia eutropha H16

    Energy Technology Data Exchange (ETDEWEB)

    Brigham, CJ; Speth, DR; Rha, C; Sinskey, AJ

    2012-10-22

    Poly(3-hydroxybutyrate) (PHB) production and mobilization in Ralstonia eutropha are well studied, but in only a few instances has PHB production been explored in relation to other cellular processes. We examined the global gene expression of wild-type R. eutropha throughout the PHB cycle: growth on fructose, PHB production using fructose following ammonium depletion, and PHB utilization in the absence of exogenous carbon after ammonium was resupplied. Our results confirm or lend support to previously reported results regarding the expression of PHB-related genes and enzymes. Additionally, genes for many different cellular processes, such as DNA replication, cell division, and translation, are selectively repressed during PHB production. In contrast, the expression levels of genes under the control of the alternative sigma factor sigma(54) increase sharply during PHB production and are repressed again during PHB utilization. Global gene regulation during PHB production is strongly reminiscent of the gene expression pattern observed during the stringent response in other species. Furthermore, a ppGpp synthase deletion mutant did not show an accumulation of PHB, and the chemical induction of the stringent response with DL-norvaline caused an increased accumulation of PHB in the presence of ammonium. These results indicate that the stringent response is required for PHB accumulation in R. eutropha, helping to elucidate a thus-far-unknown physiological basis for this process.

  16. Arabidopsis ethylene-response gene ETR1: Similiarity of product to two-component regulators

    Energy Technology Data Exchange (ETDEWEB)

    Chang, C.; Kwok, S.F.; Bleecker, A.B.; Meyerowitz, E.M. (California Institute of Technology, Pasadena, CA (United States))

    1993-10-22

    Ethylene behaves as a hormone in plants, regulating such aspects of growth and development as fruit ripening, flower senescence, and abscission. Ethylene insensitivity is conferred by dominant mutations in the ETR1 gene early in the ethylene signal transduction pathway of Arabidopsis thaliana. The ETR1 gene was cloned by the method of chromosome walking. Each of the four known etr1 mutant alleles contains a missense mutation near the amino terminus of the predicted protein. Although the sequence of the amino-terminal half of the deduced ETR1 protein appears to be novel, the carboxyl-terminal half is similar in sequence to both components of the prokaryotic family of signal transducers known as the two-component systems. Thus, an early step in ethylene signal transduction in plants may involve transfer of phosphate as in prokaryotic two-component systems. The dominant etr1-1 mutant gene conferred ethylene insensitivity to wild-type Arabidopsis plants when introduced by transformation.

  17. Expression of porcine sapovirus VP1 gene and VP1 specific monoclonal antibody production.

    Science.gov (United States)

    Ryu, Min-Sang; Jung, Eun-Hye; Cho, Kyoung-Oh; Kang, Shien-Young

    2012-06-01

    Sapovirus (SaV) is an agent of human and porcine gastroenteritis and a member of the family Caliciviridae. SaV has been classified based on VP1 full gene nucleotide sequences into five genogroups (GI-GV), among which GIII is known to infect pigs. The VP1 folds into two major domains designated S and P for the shell and protruding domain, respectively. The P domain is divided into two subdomains, P1 and P2. In this study, the VP1 full gene and the S, P, and P2 regions of the VP1 gene of porcine SaV were expressed using a baculovirus expression system. Expressed proteins in the recombinant virus were confirmed by polymerase chain reaction, indirect fluorescence antibody (IFA) testing, and Western blot analysis. Four hybridomas secreting VP1-specific monoclonal antibodies (MAbs) against porcine sapovirus were generated. Four MAbs were characterized according to their IFA and Western blot analysis results. All of the hybridomas produced in this study secreted MAbs binding to S domain of VP1 protein specifically. The MAbs produced in this study can be used as specific diagnostic reagents for detecting porcine SaV.

  18. [Production and study of Bacillus subtilis mutants for genes involved in nucleoside catabolism].

    Science.gov (United States)

    Rumiantseva, E V; Sukhodolets, V V; Smirnov, Iu V

    1979-01-01

    By means of selection for a low thymine requirement the mutants fo thymine auxotrophs for deoxyriboaldolase (dra) and phosphodeoxyribomutase (drm) genes were obtained. Besides the mutants for pyrimidinenucleoside phosphorylase gene (pdp) were olso isolated using selection on the fluorodeoxyuridine resistance. The latter enzyme provides for pyrimidine nucleosides catabolism (thymidine, uridine) in Bacilli, as well as the conversion of exogenous thymine to thymidine in thymine auxotrophs. The data obtained when studying the deo-enzymes activities in various types of the mutants and also under the condition of induction by thymidine and acetoaldehyde are in accordance with the assumption that deoxyriboso-5-phosphate is an inductor of the deo-enzymes in Bacillus subtilis. The genes dra and pdp were tightly linked as it had been shown by the transformation experiments; in contrast, no linkage was revealed between dra and drm or pdp and drm. A secondary mutation (adn), not linked with dra and blocking the ability of bacteria to catabolise adenosine (purine nucleoside phosphorylase activity remains constant) was found in some dra-mutants.

  19. Phevalin (aureusimine B) production by Staphylococcus aureus biofilm and impacts on human keratinocyte gene expression.

    Science.gov (United States)

    Secor, Patrick R; Jennings, Laura K; James, Garth A; Kirker, Kelly R; Pulcini, Elinor Delancey; McInnerney, Kate; Gerlach, Robin; Livinghouse, Tom; Hilmer, Jonathan K; Bothner, Brian; Fleckman, Philip; Olerud, John E; Stewart, Philip S

    2012-01-01

    Staphylococcus aureus biofilms are associated with chronic skin infections and are orders of magnitude more resistant to antimicrobials and host responses. S. aureus contains conserved nonribosomal peptide synthetases that produce the cyclic dipeptides tyrvalin and phevalin (aureusimine A and B, respectively). The biological function of these compounds has been speculated to be involved in virulence factor gene expression in S. aureus, protease inhibition in eukaryotic cells, and interspecies bacterial communication. However, the exact biological role of these compounds is unknown. Here, we report that S. aureus biofilms produce greater amounts of phevalin than their planktonic counterparts. Phevalin had no obvious impact on the extracellular metabolome of S. aureus as measured by high-performance liquid chromatography-mass spectrometry and nuclear magnetic resonance. When administered to human keratinocytes, phevalin had a modest effect on gene expression. However, conditioned medium from S. aureus spiked with phevalin amplified differences in keratinocyte gene expression compared to conditioned medium alone. Phevalin may be exploited as potential biomarker and/or therapeutic target for chronic, S. aureus biofilm-based infections.

  20. Production of transgenic pigs over-expressing the antiviral gene Mx1.

    Science.gov (United States)

    Yan, Quanmei; Yang, Huaqiang; Yang, Dongshan; Zhao, Bentian; Ouyang, Zhen; Liu, Zhaoming; Fan, Nana; Ouyang, Hongsheng; Gu, Weiwang; Lai, Liangxue

    2014-01-01

    The myxovirus resistance gene (Mx1) has a broad spectrum of antiviral activities. It is therefore an interesting candidate gene to improve disease resistance in farm animals. In this study, we report the use of somatic cell nuclear transfer (SCNT) to produce transgenic pigs over-expressing the Mx1 gene. These transgenic pigs express approximately 15-25 times more Mx1 mRNA than non-transgenic pigs, and the protein level of Mx1 was also markedly enhanced. We challenged fibroblast cells isolated from the ear skin of transgenic and control pigs with influenza A virus and classical swine fever virus (CFSV). Indirect immunofluorescence assay (IFA) revealed a profound decrease of influenza A proliferation in Mx1 transgenic cells. Growth kinetics showed an approximately 10-fold reduction of viral copies in the transgenic cells compared to non-transgenic controls. Additionally, we found that the Mx1 transgenic cells were more resistant to CSFV infection in comparison to non-transgenic cells. These results demonstrate that the Mx1 transgene can protect against viral infection in cells of transgenic pigs and indicate that the Mx1 transgene can be harnessed to develop disease-resistant pigs.

  1. A single ataxia telangiectasia gene with a product similar to PI-3 kinase

    Energy Technology Data Exchange (ETDEWEB)

    Savitsky, K.; Bar-Shira, A.; Gilad, S.; Rotman, G.; Ziv, Y.; Vanagaite, L.; Smith, S.; Uziel, T.; Sfez, S.; Ashkenazi, M. [Tel Aviv Univ. (Israel)] [and others

    1995-06-23

    A gene, ATM, that is mutated in the autosomal recessive disorder ataxia telangiectasia (AT) was identified by positional cloning on chromosome 11q22-23. AT is characterized by cerebellar degeneration, immunodeficiency, chromosomal instability, cancer predisposition, radiation sensitivity, and cell cycle abnormalities. The disease is genetically heterogeneous, with four complementation groups that have been suspected to represent different genes. ATM, which has a transcript of 12 kilobases, was found to be mutated in AT patients from all complementation groups, indicating that it is probably the sole gene responsible for this disorder. A partial ATM complementary DNA clone of 5.9 kilobases encoded a putative protein that is similar to several yeast and mammalian phosphatidylinositol-3{prime} kinases that are involved in mitogenic signal transduction, meiotic recombination, and cell cycle control. The discovery of ATM should enhance understanding of AT and related syndromes and may allow the identification of AT heterozygotes, who are at increased risk of cancer. 54 refs., 5 figs., 1 tab.

  2. Optimization to the Culture Conditions for Phellinus Production with Regression Analysis and Gene-Set Based Genetic Algorithm.

    Science.gov (United States)

    Li, Zhongwei; Xin, Yuezhen; Wang, Xun; Sun, Beibei; Xia, Shengyu; Li, Hui; Zhu, Hu

    2016-01-01

    Phellinus is a kind of fungus and is known as one of the elemental components in drugs to avoid cancers. With the purpose of finding optimized culture conditions for Phellinus production in the laboratory, plenty of experiments focusing on single factor were operated and large scale of experimental data were generated. In this work, we use the data collected from experiments for regression analysis, and then a mathematical model of predicting Phellinus production is achieved. Subsequently, a gene-set based genetic algorithm is developed to optimize the values of parameters involved in culture conditions, including inoculum size, PH value, initial liquid volume, temperature, seed age, fermentation time, and rotation speed. These optimized values of the parameters have accordance with biological experimental results, which indicate that our method has a good predictability for culture conditions optimization.

  3. MeSH-Informed Enrichment Analysis and MeSH-Guided Semantic Similarity Among Functional Terms and Gene Products in Chicken.

    Science.gov (United States)

    Morota, Gota; Beissinger, Timothy M; Peñagaricano, Francisco

    2016-01-01

    Biomedical vocabularies and ontologies aid in recapitulating biological knowledge. The annotation of gene products is mainly accelerated by Gene Ontology (GO), and more recently by Medical Subject Headings (MeSH). Here, we report a suite of MeSH packages for chicken in Bioconductor, and illustrate some features of different MeSH-based analyses, including MeSH-informed enrichment analysis and MeSH-guided semantic similarity among terms and gene products, using two lists of chicken genes available in public repositories. The two published datasets that were employed represent (i) differentially expressed genes, and (ii) candidate genes under selective sweep or epistatic selection. The comparison of MeSH with GO overrepresentation analyses suggested not only that MeSH supports the findings obtained from GO analysis, but also that MeSH is able to further enrich the representation of biological knowledge and often provide more interpretable results. Based on the hierarchical structures of MeSH and GO, we computed semantic similarities among vocabularies, as well as semantic similarities among selected genes. These yielded the similarity levels between significant functional terms, and the annotation of each gene yielded the measures of gene similarity. Our findings show the benefits of using MeSH as an alternative choice of annotation in order to draw biological inferences from a list of genes of interest. We argue that the use of MeSH in conjunction with GO will be instrumental in facilitating the understanding of the genetic basis of complex traits.

  4. Optimization protein productivity of human interleukin-2 through codon usage, gene copy number and intracellular tRNA concentration in CHO cells.

    Science.gov (United States)

    Ou, Kua-Chun; Wang, Chih-Yang; Liu, Kuan-Ting; Chen, Yi-Ling; Chen, Yi-Chen; Lai, Ming-Derg; Yen, Meng-Chi

    2014-11-14

    Transfer RNA (tRNA) abundance is one of the critical factors for the enhancement of protein productivity in prokaryotic and eukaryotic hosts. Gene copy number of tRNA and tRNA codon usage bias are generally used to match tRNA abundance of protein-expressing hosts and to optimize the codons of recombinant proteins. Because sufficient concentration of intracellular tRNA and optimized codons of recombinant proteins enhanced translation efficiency, we hypothesized that sufficient supplement of host's tRNA improved protein productivity in mammalian cells. First, the small tRNA sequencing results of CHO-K1 cells showed moderate positive correlation with gene copy number and codon usage bias. Modification of human interleukin-2 (IL-2) through codons with high gene copy number and high codon usage bias (IL-2 HH, modified on Leu, Thr, Glu) significantly increased protein productivity in CHO-K1 cells. In contrast, modification through codons with relatively high gene copy number and low codon usage bias (IL-2 HL, modified on Ala, Thr, Val), or relatively low gene copy number and low codon usage bias (IL-2 LH, modified on Ala, Thr, Val) did not increase IL-2 productivity significantly. Furthermore, supplement of the alanine tRNA or threonine tRNA increased IL-2 productivity of IL-2 HL. In summary, we revealed a potential strategy to enhance productivity of recombinant proteins, which may be applied in production of protein drug or design of DNA vaccine.

  5. A systems biology approach to investigate the effect of pH-induced gene regulation on solvent production by Clostridium acetobutylicum in continuous culture.

    Science.gov (United States)

    Haus, Sylvia; Jabbari, Sara; Millat, Thomas; Janssen, Holger; Fischer, Ralf-Jörg; Bahl, Hubert; King, John R; Wolkenhauer, Olaf

    2011-01-19

    Clostridium acetobutylicum is an anaerobic bacterium which is known for its solvent-producing capabilities, namely regarding the bulk chemicals acetone and butanol, the latter being a highly efficient biofuel. For butanol production by C. acetobutylicum to be optimized and exploited on an industrial scale, the effect of pH-induced gene regulation on solvent production by C. acetobutylicum in continuous culture must be understood as fully as possible. We present an ordinary differential equation model combining the metabolic network governing solvent production with regulation at the genetic level of the enzymes required for this process. Parameterizing the model with experimental data from continuous culture, we demonstrate the influence of pH upon fermentation products: at high pH (pH 5.7) acids are the dominant product while at low pH (pH 4.5) this switches to solvents. Through steady-state analyses of the model we focus our investigations on how alteration in gene expression of C. acetobutylicum could be exploited to increase butanol yield in a continuous culture fermentation. Incorporating gene regulation into the model of solvent production by C. acetobutylicum enables an accurate representation of the pH-induced switch to solvent production to be obtained and theoretical investigations of possible synthetic-biology approaches to be pursued. Steady-state analyses suggest that, to increase butanol yield, alterations in the expression of single solvent-associated genes are insufficient; a more complex approach targeting two or more genes is required.

  6. Overexpression of the primary sigma factor gene sigA improved carotenoid production by Corynebacterium glutamicum: Application to production of β-carotene and the non-native linear C50 carotenoid bisanhydrobacterioruberin

    Directory of Open Access Journals (Sweden)

    Hironori Taniguchi

    2017-06-01

    Full Text Available Corynebacterium glutamicum shows yellow pigmentation due to biosynthesis of the C50 carotenoid decaprenoxanthin and its glycosides. This bacterium has been engineered for production of various non-native cyclic C40 and C50 carotenoids such as β-carotene, astaxanthin or sarcinaxanthin. In this study, the effect of modulating gene expression more broadly by overexpression of sigma factor genes on carotenoid production by C. glutamicum was characterized. Overexpression of the primary sigma factor gene sigA improved lycopene production by recombinant C. glutamicum up to 8-fold. In C. glutamicum wild type, overexpression of sigA led to 2-fold increased accumulation of the native carotenoid decaprenoxanthin in the stationary growth phase. Under these conditions, genes related to thiamine synthesis and aromatic compound degradation showed increased RNA levels and addition of thiamine and the aromatic iron chelator protocatechuic acid to the culture medium enhanced carotenoid production when sigA was overexpressed. Deletion of the gene for the alternative sigma factor SigB, which is expected to replace SigA in RNA polymerase holoenzymes during transition to the stationary growth phase, also increased carotenoid production. The strategy of sigA overexpression could be successfully transferred to production of the non-native carotenoids β-carotene and bisanhydrobacterioruberin (BABR. Production of the latter is the first demonstration that C. glutamicum may accumulate a non-native linear C50 carotenoid instead of the native cyclic C50 carotenoid decaprenoxanthin.

  7. Bagging Treatment Influences Production of C6 Aldehydes and Biosynthesis-Related Gene Expression in Peach Fruit Skin

    Directory of Open Access Journals (Sweden)

    Ji-Yuan Shen

    2014-08-01

    Full Text Available Bagging is a useful method to improve fruit quality by altering its exposure to light, whereas its effect on fruit volatiles production is inconsistent, and the genes responsible for the observed changes remain unknown. In the present study, single-layer yellow paper bags were used to study the effects of bagging treatment on the formation of C6 aldehydes in peach fruit (Prunus persica L. Batsch, cv. Yulu over two succeeding seasons. Higher concentrations of n-hexanal and (E-2-hexenal, which are characteristic aroma volatiles of peach fruit, were induced by bagging treatment. After bagging treatment, peach fruit had significantly higher LOX and HPL enzyme activities, accompanying increased contents of C6 aldehydes. The gene expression data obtained through real-time PCR showed that no consistent significant differences in transcript levels of LOX genes were observed over the two seasons, but significantly up-regulated expression was found for PpHPL1 after bagging treatment In addition, bagging-treated fruit produced more (E-2-hexenal and had higher expression levels of PpHPL1 during postharvest ripening at room temperature. The regulatory role of the LOX-HPL pathway on the biosynthesis of n-hexanal and (E-2-hexenal in response to bagging treatment during peach fruit development is discussed in the text.

  8. Production of Transgenic Anliucheng Sweet Orange (Citrus sinensis Osbeck) with Xa21 Gene for Potential Canker Resistance

    Institute of Scientific and Technical Information of China (English)

    LI Ding-li; XIAO Xuan; and GUO Wen-wu

    2014-01-01

    Citrus canker, an epidemic quarantine disease caused by Xanthomonas axonopodis pv. citri, has brought a great damage in citrus production worldwide. Herein, a rice PRR (pattern recognition receptor) gene Xa21 together with GUS reporter gene and hygromycin phosphotransferase gene (HPT) was introduced into Anliucheng sweet orange (Citrus sinensis Osbeck) via Agrobacterium-mediated transformation of embryogenic callus. The transgenic calluses were screened on MT basal medium containing hygromycin (HYG) and detected by histochemical GUS staining. The transgenic plantlets were recovered through somatic embryogenesis pathway. The regenerated plantlets were accustomed to and maintained in the greenhouse. The transgene integration of recovered plantlets was identiifed by PCR and Southern blot hybridization. It showed that all the transgenic plantlets tested had undergone single copy integration, the expression of Xa21 in eight different transgenic lines detected by qRT-PCR can be divided into three grades, high for T5 and T6, middle for T4 and low for the rest. The tolerance to citrus canker disease of the three recovered transgenic lines T2, T4 and T6 was assessed by in vitro pin-puncture inoculation. The results showed that all the three transgenic lines conferred improved resistance to citrus canker bacterium infection and the T4 transgenic line displayed the highest resistance. The mechanism and feasibility of rice Xa21 in triggering innate immunity in citrus was brielfy discussed.

  9. Modulation of conidia production and expression of the gene bbrgs1 from Beauveria bassiana by oxygen pulses and light.

    Science.gov (United States)

    Rodriguez-Gomez, Divanery; Marcial-Quino, Jaime; Loera, Octavio

    2015-09-01

    Light and oxidant states affect the conidiation in diverse fungi, although the response has not been described when both stimuli are applied simultaneously. Conidial production and quality in Beauveria bassiana were analysed under four conditions for a wild-type (wt) strain and a previously isolated mutant (mt): normal atmosphere (21% O2; NA) or oxygen-enriched pulses (26% O2; OEP), with either light (L) or darkness (D). The response was complemented by following the expression of the bbrgs1 gene, encoding a regulator of the G-protein signal associated to conidia production. Conidiation was not significantly affected in the mutant strain by any condition (highest value with NA-L: 2.7×10(8)concm(-2)). Relative to maximal levels under NA (NA-D: 4×10(7)concm(2)), the wt strain diminished conidiation by 34-fold under OEP. The expression of bbrgs1 was higher (up to 188 times) in the mutant strain in every condition relative to the wt strain, in fact expression levels were consistent with the conidiation yields between strains. Viability and hydrophobicity were less affected by culture conditions, although pathogenicity parameters improved in conidia from OEP. The response to OEP, either with light or darkness, was strain-dependent for conidial production, viability, hydrophobicity and infectivity of conidia, then these parameters could be modulated in mass production processes. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Effect on milk production of vaccination with a bovine herpesvirus 1 gene-deleted vaccine.

    Science.gov (United States)

    Bosch, J C; Frankena, K; van Oirschot, J T

    1997-02-22

    A field trial was conducted to determine the effect of vaccination with an inactivated bovine herpesvirus 1 (BHV1) gE-negative marker vaccine on the milk production of dairy cows. The daily milk yield of 455 cows in six herds was measured electronically from six days before vaccination until 14 days after vaccination. The treatment consisted of two injections with either vaccine or placebo, both at an interval of four weeks. There was a small, but significant (P < 0.05), decrease of about 1.4 litres per cow in milk production after a double vaccination, the negative effect being slightly greater after the second vaccination.

  11. The Sinorhizobium meliloti ntrX gene is involved in succinoglycan production, motility, and symbiotic nodulation on alfalfa.

    Science.gov (United States)

    Wang, Dong; Xue, Haiying; Wang, Yiwen; Yin, Ruochun; Xie, Fang; Luo, Li

    2013-12-01

    Rhizobia establish a symbiotic relationship with their host legumes to induce the formation of nitrogen-fixing nodules. This process is regulated by many rhizobium regulators, including some two-component regulatory systems (TCSs). NtrY/NtrX, a TCS that was first identified in Azorhizobium caulinodans, is required for free-living nitrogen metabolism and symbiotic nodulation on Sesbania rostrata. However, its functions in a typical rhizobium such as Sinorhizobium meliloti remain unclear. Here we found that the S. meliloti response regulator NtrX but not the histidine kinase NtrY is involved in the regulation of exopolysaccharide production, motility, and symbiosis with alfalfa. A plasmid insertion mutant of ntrX formed mucous colonies, which overproduced succinoglycan, an exopolysaccharide, by upregulating its biosynthesis genes. This mutant also exhibited motility defects due to reduced flagella and decreased expression of flagellins and regulatory genes. The regulation is independent of the known regulatory systems of ExoR/ExoS/ChvI, EmmABC, and ExpR. Alfalfa plants inoculated with the ntrX mutant were small and displayed symptoms of nitrogen starvation. Interestingly, the deletion mutant of ntrY showed a phenotype similar to that of the parent strain. These findings demonstrate that the S. meliloti NtrX is a new regulator of succinoglycan production and motility that is not genetically coupled with NtrY.

  12. Bioengineering of the Plant Culture of Capsicum frutescens with Vanillin Synthase Gene for the Production of Vanillin.

    Science.gov (United States)

    Chee, Marcus Jenn Yang; Lycett, Grantley W; Khoo, Teng-Jin; Chin, Chiew Foan

    2017-01-01

    Production of vanillin by bioengineering has gained popularity due to consumer demand toward vanillin produced by biological systems. Natural vanillin from vanilla beans is very expensive to produce compared to its synthetic counterpart. Current bioengineering works mainly involve microbial biotechnology. Therefore, alternative means to the current approaches are constantly being explored. This work describes the use of vanillin synthase (VpVAN), to bioconvert ferulic acid to vanillin in a plant system. The VpVAN enzyme had been shown to directly convert ferulic acid and its glucoside into vanillin and its glucoside, respectively. As the ferulic acid precursor and vanillin were found to be the intermediates in the phenylpropanoid biosynthetic pathway of Capsicum species, this work serves as a proof-of-concept for vanillin production using Capsicum frutescens (C. frutescens or hot chili pepper). The cells of C. frutescens were genetically transformed with a codon optimized VpVAN gene via biolistics. Transformed explants were selected and regenerated into callus. Successful integration of the gene cassette into the plant genome was confirmed by polymerase chain reaction. High-performance liquid chromatography was used to quantify the phenolic compounds detected in the callus tissues. The vanillin content of transformed calli was 0.057% compared to 0.0003% in untransformed calli.

  13. An extended gene protein/products Boolean network model including post-transcriptional regulation.

    Science.gov (United States)

    Benso, Alfredo; Di Carlo, Stefano; Politano, Gianfranco; Savino, Alessandro; Vasciaveo, Alessandro

    2014-05-07

    Networks Biology allows the study of complex interactions between biological systems using formal, well structured, and computationally friendly models. Several different network models can be created, depending on the type of interactions that need to be investigated. Gene Regulatory Networks (GRN) are an effective model commonly used to study the complex regulatory mechanisms of a cell. Unfortunately, given their intrinsic complexity and non discrete nature, the computational study of realistic-sized complex GRNs requires some abstractions. Boolean Networks (BNs), for example, are a reliable model that can be used to represent networks where the possible state of a node is a boolean value (0 or 1). Despite this strong simplification, BNs have been used to study both structural and dynamic properties of real as well as randomly generated GRNs. In this paper we show how it is possible to include the post-transcriptional regulation mechanism (a key process mediated by small non-coding RNA molecules like the miRNAs) into the BN model of a GRN. The enhanced BN model is implemented in a software toolkit (EBNT) that allows to analyze boolean GRNs from both a structural and a dynamic point of view. The open-source toolkit is compatible with available visualization tools like Cytoscape and allows to run detailed analysis of the network topology as well as of its attractors, trajectories, and state-space. In the paper, a small GRN built around the mTOR gene is used to demonstrate the main capabilities of the toolkit. The extended model proposed in this paper opens new opportunities in the study of gene regulation. Several of the successful researches done with the support of BN to understand high-level characteristics of regulatory networks, can now be improved to better understand the role of post-transcriptional regulation for example as a network-wide noise-reduction or stabilization mechanisms.

  14. An extended gene protein/products boolean network model including post-transcriptional regulation

    Science.gov (United States)

    2014-01-01

    Background Networks Biology allows the study of complex interactions between biological systems using formal, well structured, and computationally friendly models. Several different network models can be created, depending on the type of interactions that need to be investigated. Gene Regulatory Networks (GRN) are an effective model commonly used to study the complex regulatory mechanisms of a cell. Unfortunately, given their intrinsic complexity and non discrete nature, the computational study of realistic-sized complex GRNs requires some abstractions. Boolean Networks (BNs), for example, are a reliable model that can be used to represent networks where the possible state of a node is a boolean value (0 or 1). Despite this strong simplification, BNs have been used to study both structural and dynamic properties of real as well as randomly generated GRNs. Results In this paper we show how it is possible to include the post-transcriptional regulation mechanism (a key process mediated by small non-coding RNA molecules like the miRNAs) into the BN model of a GRN. The enhanced BN model is implemented in a software toolkit (EBNT) that allows to analyze boolean GRNs from both a structural and a dynamic point of view. The open-source toolkit is compatible with available visualization tools like Cytoscape and allows to run detailed analysis of the network topology as well as of its attractors, trajectories, and state-space. In the paper, a small GRN built around the mTOR gene is used to demonstrate the main capabilities of the toolkit. Conclusions The extended model proposed in this paper opens new opportunities in the study of gene regulation. Several of the successful researches done with the support of BN to understand high-level characteristics of regulatory networks, can now be improved to better understand the role of post-transcriptional regulation for example as a network-wide noise-reduction or stabilization mechanisms. PMID:25080304

  15. Characterization of a Thioredoxin-1 Gene from Taenia solium and Its Encoding Product.

    Science.gov (United States)

    Jiménez, Lucía; Rodríguez-Lima, Oscar; Ochoa-Sánchez, Alicia; Landa, Abraham

    2015-01-01

    Taenia solium thioredoxin-1 gene (TsTrx-1) has a length of 771 bp with three exons and two introns. The core promoter gene presents two putative stress transcription factor binding sites, one putative TATA box, and a transcription start site (TSS). TsTrx-1 mRNA is expressed higher in larvae than in adult. This gene encodes a protein of 107 amino acids that presents the Trx active site (CGPC), the classical secondary structure of the thioredoxin fold, and the highest degree of identity with the Echinococcus granulosus Trx. A recombinant TsTrx-1 (rTsTrx-1) was produced in Escherichia coli with redox activity. Optimal activity for rTsTrx-1 was at pH 6.5 in the range of 15 to 25°C. The enzyme conserved activity for 3 h and lost it in 24 h at 37°C. rTsTrx-1 lost 50% activity after 1 h and lost activity completely in 24 h at temperatures higher than 55°C. Best storage temperature for rTsTrx-1 was at -70°C. It was inhibited by high concentrations of H₂O₂ and methylglyoxal (MG), but it was inhibited neither by NaCl nor by anti-rTsTrx-1 rabbit antibodies that strongly recognized a ~12 kDa band in extracts from several parasites. These TsTrx-1 properties open the opportunity to study its role in relationship T. solium-hosts.

  16. Evaluation of AMPK Genes as Candidates for Production Traits in Buffalo Breeds of Pakistan

    Directory of Open Access Journals (Sweden)

    T. Hussain

    2010-02-01

    Full Text Available The 5’-activated protein kinase (AMPK also called PRKA is a heterotrimeric protein complex that regulates cellular metabolism in response to nutritional stress in mammals. Total length of AMPK gene is 6500 base pairs. AMPK γ3 has 884 base pairs comprises of exon 3, intron 3 and exon 4. AMPK γ3 gene was studied on DNA from three buffalo breeds (Nili, Ravi and Nili Ravi of Pakistan. Amplification of this region was done from position 918 in exon to position 1802 just downstream of exon 4, using primers U1A-GAGCAAGGAGACAGCACTTCA (918-938 and U2B-ACCTGTAGCATGGTGTC GAAGA (1781- 1802 with Amplictaq Gold, at annealing temperature 60oC. Sequencing of PRKA γ3 UP SEQ1 5’-GACCTCAGCATCCAGGCT and PRKA γ3 UP SEQ2 5’-GACAGTAACTCCATCTTCCA was done. The results showed that at position 1069, Allelic frequency of C/T was 0.35, T/T was 0.05 and frequency of C/C was 0.40. At position 1343, frequency of A/G was 0.1 and A/A was 0.9. At 1381 position, frequency of C/T was 0.35, T/T was 0.05 and C/C was 0.6. At position 1488, the A/G was 0.35, A/A was 0.05and G/G was 0.6. The detected SNP at 1343 is A/G which is the ancient haplotypes of PRKAG3 in Nili Ravi buffalo breeds from Pakistan. These SNPs in AMPK gene can be used as marker for efficient utilization of energy in these three buffalo breeds of Pakistan that will increase the economic returns to farmers.

  17. Polymorphisms at Cytokine Genes May Determine the Effect of Vitamin E on Cytokine Production in the Elderly1–3

    Science.gov (United States)

    Belisle, Sarah E.; Leka, Lynette S.; Delgado-Lista, Javier; Jacques, Paul F.; Ordovas, Jose M.; Meydani, Simin Nikbin

    2009-01-01

    Vitamin E has been shown to affect cytokine production. However, individual response to vitamin E supplementation varies. Previous studies indicate that cytokine production is heritable and common single nucleotide polymorphisms (SNP) may explain differences in cytokine production between individuals. We hypothesize that the differential response to the immunomodulatory actions of vitamin E reflects genetic differences among individuals, including SNP at cytokine genes that modulate cytokine production. We used data from a double-blind, placebo-controlled 1-y vitamin E (182 mg d,l-α-tocopherol) intervention study in elderly men and women (mean age 83 y) to test this hypothesis (vitamin E, n = 47; placebo, n = 63). We found that the effect of vitamin E on tumor necrosis factor (TNF)-α production in whole blood stimulated for 24 h with lipopolysaccharide (1.0 mg/L) is dependent on TNFα -308G > A. Participants with the A/A and A/G genotypes at TNFα -308G > A who were treated with vitamin E had lower TNFα production than those with the A allele treated with placebo. These observations suggest that individual immune responses to vitamin E supplementation are in part mediated by genetic factors. Because the A allele at TNFα has been previously associated with higher TNFα levels in whole blood and isolated immune cells, our observations suggest that the antiinflammatory effect of vitamin E is specific to those genetically predisposed to higher inflammation. Further studies are needed to determine the biological mechanism driving the interaction between vitamin E treatment and TNFα -308G > A and its implications for disease resistance. PMID:19710156

  18. Nitrile-synthesizing enzyme: Gene cloning, overexpression and application for the production of useful compounds

    OpenAIRE

    Kumano, Takuto; Takizawa, Yuko; Shimizu, Sakayu; Kobayashi, Michihiko

    2016-01-01

    One of the nitrile-synthesizing enzymes, β-cyano-L-alanine synthase, catalyzes β-cyano-L-alanine (β-CNAla) from potassium cyanide and O-acetyl-L-serine or L-cysteine. We have identified this enzyme from Pseudomonas ovalis No. 111. In this study, we cloned the β-CNAla synthase gene and expressed it in Escherichia coli and Rhodococcus rhodochrous. Furthermore, we carried out co-expression of β-CNAla synthase with nitrilase or nitrile hydratases in order to synthesize aspartic acid and asparagin...

  19. Mass spectrometric analysis of putative capa-gene products in Musca domestica and Neobellieria bullata.

    Science.gov (United States)

    Predel, Reinhard; Russell, William K; Tichy, Shane E; Russell, David H; Nachman, Ronald J

    2003-10-01

    Neuropeptides of the capa-gene are typical of the abdominal neurosecretory system of insects. In this study, we investigated these peptides in two widely distributed and large pest flies, namely Musca domestica and Neobellieria bullata. Using a combination of MALDI-TOF and ESI-QTOF mass spectrometry, periviscerokinins and a pyrokinin were analyzed from single perisympathetic organ preparations. The species-specific peptide sequences differ remarkably between the related dipteran species. These differences could make it possible to develop peptide-analogs with group- or species-specific efficacy.

  20. Deoxycytidine kinase and deoxyguanosine kinase of Lactobacillus acidophilus R-26 are colinear products of a single gene.

    Science.gov (United States)

    Ma, N; Ikeda, S; Guo, S; Fieno, A; Park, I; Grimme, S; Ikeda, T; Ives, D H

    1996-12-10

    Three of the four deoxynucleoside kinases required for growth of Lactobacillus acidophilus R-26 exist as heterodimeric pairs specific for deoxyadenosine (dAK) and deoxycytidine (dCK) or dAK and deoxyguanosine (dGK). However, only two tandem genes, dak/dgk, are found, and are expressed only as dAK/dGK in transformed Escherichia coli. Sequencing peptides spanning 63% of the native dCK subunit revealed a sequence identical to that deduced from dgk (beginning MTVIVL...), except that dCK lacks residues 2 and 3 (dCK is M..IVL; dGK is .TVIVL). Also, mass spectrometry indicates that native dCK and dGK subunits are identical in mass adjusted for the first three residues. Furthermore, the native enzymes have identical isoelectric pH values, indicating an equal number of charged residues. To enable E. coli to express peptide having the native dCK sequence, codons 2 and 3 were deleted from the dgk portion of the tandem genes, resulting in expression of protein having the specificities and regulatory properties of native dAK/dCK, including heterotropic stimulation of dAK activity by deoxycytidine or dCTP (not deoxyguanosine or dGTP) and end-product inhibition of the respective activities by dATP and dCTP. Subcloning normal and mutant dgk yielded homodimeric dGK and dCK, respectively. The dCK homodimer strongly resembles human dCK, with a low K(m) for deoxycytidine, the ability to phosphorylate deoxyadenosine and deoxyguanosine at much higher K(m) values, and end-product inhibition by dCTP. Thus two distinct and specific enzymes evidently are derived from a single Lactobacillus gene. The mechanism by which this occurs in vivo has yet to be elucidated.

  1. Enhanced production of steviol glycosides in mycorrhizal plants: a concerted effect of arbuscular mycorrhizal symbiosis on transcription of biosynthetic genes.

    Science.gov (United States)

    Mandal, Shantanu; Upadhyay, Shivangi; Singh, Ved Pal; Kapoor, Rupam

    2015-04-01

    Stevia rebaudiana (Bertoni) produces steviol glycosides (SGs)--stevioside (stev) and rebaudioside-A (reb-A) that are valued as low calorie sweeteners. Inoculation with arbuscular mycorrhizal fungi (AMF) augments SGs production, though the effect of this interaction on SGs biosynthesis has not been studied at molecular level. In this study transcription profiles of eleven key genes grouped under three stages of the SGs biosynthesis pathway were compared. The transcript analysis showed upregulation of genes encoding 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway enzymes viz.,1-deoxy-D-xylulose 5-phospate synthase (DXS), 1-deoxy-D-xylulose 5-phospate reductoisomerase (DXR) and 2-C-methyl-D-erytrithol 2,4-cyclodiphosphate synthase (MDS) in mycorrhizal (M) plants. Zn and Mn are imperative for the expression of MDS and their enhanced uptake in M plants could be responsible for the increased transcription of MDS. Furthermore, in the second stage of SGs biosynthesis pathway, mycorrhization enhanced the transcription of copalyl diphosphate synthase (CPPS) and kaurenoic acid hydroxylase (KAH). Their expression is decisive for SGs biosynthesis as CPPS regulates flow of metabolites towards synthesis of kaurenoid precursors and KAH directs these towards steviol synthesis instead of gibberellins. In the third stage glucosylation of steviol to reb-A by four specific uridine diphosphate (UDP)-dependent glycosyltransferases (UGTs) occurs. While higher transcription of all the three characterized UGTs in M plants explains augmented production of SGs; higher transcript levels of UGT76G1, specifically improved reb-A to stev ratio implying increased sweetness. The work signifies that AM symbiosis upregulates the transcription of all eleven SGs biosynthesis genes as a result of improved nutrition and enhanced sugar concentration due to increased photosynthesis in M plants.

  2. Detection of Integrase Gene in E. coli Isolated from Pigs at Different Stages of Production System

    Directory of Open Access Journals (Sweden)

    Eulalia de la Torre

    2014-01-01

    Full Text Available Integrons are one of the genetic elements involved in the acquisition of antibiotic resistance. The aim of the present research is to investigate the presence of integrons in commensal Escherichia coli (E. coli strains, isolated from pigs at different stages of production system and from the environment in an Argentinian farm. Five sows postpartum and five randomly chosen piglets from each litter were sampled by rectal swabs. They were sampled again at day 21 and at day 70. Environmental samples from the farm were also obtained. E. coli containing any integron class or combination of both integrons was detected by polymerase chain reaction in 100% of sows and in piglets at different stages of production: farrowing pen stage 68.1%;, weaning 60%, and growing/finishing 85.8%, showing an increase along the production system. From environmental samples 78.4% of E. coli containing any integron class was detected. We conclude that animals and farm environment can act as reservoirs for potential spread of resistant bacteria by means of mobile genetic elements as integrons, which has a major impact on production of food animals and that can reach man through the food chain, constituting a problem for public health.

  3. Relationship between fumonisin production and FUM gene expression in Fusarium verticillioides under different environmental conditions

    DEFF Research Database (Denmark)

    Fanelli, Francesca; Iversen, Anita; Logrieco, Antonio F.;

    2013-01-01

    Fusarium verticillioides is the main source of fumonisins, a group of mycotoxins that can contaminate maize-based food and feed and cause diseases in humans and animals. The study of the effect of different environmental conditions on toxin production should provide information that can be used...

  4. Disruption of the acetate kinase (ack) gene of Clostridium acetobutylicum results in delayed acetate production

    NARCIS (Netherlands)

    Kuit, W.; Minton, N.P.; Lopez Contreras, A.M.; Eggink, G.

    2012-01-01

    In microorganisms, the enzyme acetate kinase (AK) catalyses the formation of ATP from ADP by de-phosphorylation of acetyl phosphate into acetic acid. A mutant strain of Clostridium acetobutylicum lacking acetate kinase activity is expected to have reduced acetate and acetone production compared to

  5. Disruption of the acetate kinase (ack) gene of Clostridium acetobutylicum results in delayed acetate production

    NARCIS (Netherlands)

    Kuit, W.; Minton, N.P.; Lopez Contreras, A.M.; Eggink, G.

    2012-01-01

    In microorganisms, the enzyme acetate kinase (AK) catalyses the formation of ATP from ADP by de-phosphorylation of acetyl phosphate into acetic acid. A mutant strain of Clostridium acetobutylicum lacking acetate kinase activity is expected to have reduced acetate and acetone production compared to t

  6. Detection of Integrase Gene in E. coli Isolated from Pigs at Different Stages of Production System.

    Science.gov (United States)

    de la Torre, Eulalia; Colello, Rocío; Padola, Nora Lía; Etcheverría, Analía; Rodríguez, Edgardo; Amanto, Fabián; Tapia, María Ofelia; Soraci, Alejandro Luis

    2014-01-01

    Integrons are one of the genetic elements involved in the acquisition of antibiotic resistance. The aim of the present research is to investigate the presence of integrons in commensal Escherichia coli (E. coli) strains, isolated from pigs at different stages of production system and from the environment in an Argentinian farm. Five sows postpartum and five randomly chosen piglets from each litter were sampled by rectal swabs. They were sampled again at day 21 and at day 70. Environmental samples from the farm were also obtained. E. coli containing any integron class or combination of both integrons was detected by polymerase chain reaction in 100% of sows and in piglets at different stages of production: farrowing pen stage 68.1%;, weaning 60%, and growing/finishing 85.8%, showing an increase along the production system. From environmental samples 78.4% of E. coli containing any integron class was detected. We conclude that animals and farm environment can act as reservoirs for potential spread of resistant bacteria by means of mobile genetic elements as integrons, which has a major impact on production of food animals and that can reach man through the food chain, constituting a problem for public health.

  7. IL-32θ gene expression in acute myeloid leukemia suppresses TNF-α production.

    Science.gov (United States)

    Kim, Man Sub; Kang, Jeong-Woo; Jeon, Jae-Sik; Kim, Jae Kyung; Kim, Jong Wan; Hong, Jintae; Yoon, Do-Young

    2015-12-01

    The proinflammatory cytokine TNF-α is highly expressed in patients with acute myeloid leukemia (AML) and has been demonstrated to induce rapid proliferation of leukemic blasts. Thus suppressing the production of TNF-α is important because TNF-α can auto-regulate own expression through activation of NF-κB and p38 mitogen-activated protein kinase (MAPK). In this study, we focused on the inhibitory effect of IL-32θ on TNF-α production in acute myeloid leukemia. Approximately 38% of patients with AML express endogenous IL-32θ, which is not expressed in healthy individuals. Furthermore, plasma samples were classified into groups with or without IL-32θ; then, we measured proinflammatory cytokine TNF-α, IL-1β, and IL-6 levels. TNF-α production was not increased in patients with IL-32θ expression than that in the no-IL-32θ group. Using an IL-32θ stable expression system in leukemia cell lines, we found that IL-32θ attenuated phorbol 12-myristate 13-acetate (PMA)-induced TNF-α production. IL-32θ inhibited phosphorylation of p38 MAPK, inhibitor of κB (IκB), and nuclear factor κB (NF-κB), which are key positive regulators of TNF-α expression, and inhibited nuclear translocation of NF-κB. Moreover, the presence of IL-32θ attenuated TNF-α promoter activity and the binding of NF-κB with the TNF-α promoter. In addition, IL-32γ-induced TNF-α production has no correlation with inhibition of TNF-α via IL-32θ expression. Thus, IL-32θ may serve as a potent inhibitor of TNF-α in patients with AML.

  8. Engineering the Production of Major Catechins by Escherichia coli Carrying Metabolite Genes of Camellia sinensis

    Directory of Open Access Journals (Sweden)

    Kabir Mustapha Umar

    2012-01-01

    Full Text Available A mimicked biosynthetic pathway of catechin metabolite genes from C. sinensis, consisting of flavanone 3 hydroxylase (F3H, dihydroflavonol reductase (DFR, and leucoanthocyanidin reductase (LCR, was designed and arranged in two sets of constructs: (a single promoter in front of F3H and ribosome-binding sequences both in front of DFR and LCR; (b three different promoters with each in the front of the three genes and ribosome-binding sequences at appropriate positions. Recombinant E. coli BL (DE3 harbouring the constructs were cultivated for 65 h at 26°C in M9 medium consisting of 40 g/L glucose, 1 mM IPTG, and 3 mM eriodictyol. Compounds produced were extracted in ethyl acetate in alkaline conditions after 1 h at room temperature and identified by HPLC. Two of the four major catechins, namely, (−-epicatechin (0.01  and (−-epicatechin gallate (0.36 mg/L, and two other types ((+-catechin hydrate (0.13 mg/L and (−-catechin gallate (0.04 mg/L were successfully produced.

  9. Replication, gene expression and particle production by a consensus Merkel Cell Polyomavirus (MCPyV genome.

    Directory of Open Access Journals (Sweden)

    Friederike Neumann

    Full Text Available Merkel Cell Polyomavirus (MCPyV genomes are clonally integrated in tumor tissues of approximately 85% of all Merkel cell carcinoma (MCC cases, a highly aggressive tumor of the skin which predominantly afflicts elderly and immunosuppressed patients. All integrated viral genomes recovered from MCC tissue or MCC cell lines harbor signature mutations in the early gene transcript encoding for the large T-Antigen (LT-Ag. These mutations selectively abrogate the ability of LT-Ag to support viral replication while still maintaining its Rb-binding activity, suggesting a continuous requirement for LT-Ag mediated cell cycle deregulation during MCC pathogenesis. To gain a better understanding of MCPyV biology, in vitro MCPyV replication systems are required. We have generated a synthetic MCPyV genomic clone (MCVSyn based on the consensus sequence of MCC-derived sequences deposited in the NCBI database. Here, we demonstrate that transfection of recircularized MCVSyn DNA into some human cell lines recapitulates efficient replication of the viral genome, early and late gene expression together with virus particle formation. However, serial transmission of infectious virus was not observed. This in vitro culturing system allows the study of viral replication and will facilitate the molecular dissection of important aspects of the MCPyV lifecycle.

  10. A GmAOX2b antisense gene compromises vegetative growth and seed production in soybean.

    Science.gov (United States)

    Chai, Tsun-Thai; Simmonds, Daina; Day, David A; Colmer, Timothy D; Finnegan, Patrick M

    2012-07-01

    The alternative oxidase mediates the cyanide-resistant respiratory pathway in plant mitochondria. In non-thermogenic plants, the role of alternative oxidase in plant growth and development is not well understood. Soybean (Glycine max) lines carrying a GmAOX2b antisense gene had compromised vegetative growth and reproductive performance under typical glasshouse growth conditions. The reduction in vegetative growth was demonstrated by reduction in shoot height, the number of leaves per plant and the green leaf area. Antisense plants also had decreased pod formation and seed to pod ratios, which together led to a reduction in the number and total mass of seed produced. The negative effects of the antisense gene on pod set, seed set, ovule availability and total seed mass were primarily confined to the branches, rather than the main stem. The preferential effect of alternative oxidase suppression in the branches is discussed in relation to the reproductive potential of soybean under stress. Taken together, these results demonstrate that alternative oxidase provides the benefit of sustaining plant vegetative growth and reproductive capacity in soybean.

  11. Target and specificity of a nuclear gene product that participates in mRNA 3'-end formation in Chlamydomonas chloroplasts.

    Science.gov (United States)

    Levy, H; Kindle, K L; Stern, D B

    1999-12-10

    Chloroplast mRNA maturation is catalyzed by nucleus-encoded processing enzymes. We previously described a recessive nuclear mutation (crp3) that affects 3'-end formation of several chloroplast mRNAs in Chlamydomonas reinhardtii (Levy, H., Kindle, K. L., and Stern, D. B. (1997) Plant Cell 9, 825-836). In the crp3 background, atpB mRNA lacking a 3'-inverted repeat normally required for stability accumulates as a discrete transcript. The mutation also affects the atpA gene cluster; polycistronic mRNAs with psbI or cemA 3'-ends accumulate to a lower level in the crp3 background. Here, we demonstrate that the crp3 mutation also alters 3'-end formation of psbI mRNA and cemA-containing mRNAs. A novel 3'-end is formed in monocistronic psbI transcripts, and this is the only terminus observed when the psbI 3'-untranslated region is fused to an aadA reporter gene. Accumulation of mRNAs with 3'-ends between cemA and atpH, which is immediately downstream, was reduced. However, this sequence was not recognized as a 3'-end formation element in chimeric genes. The crp3 mutation was able to confer stability to three different atpB 3'-stem-loop-disrupting mutations that lack sequence similarity, but are located at a similar distance from the translation termination codon. We propose that the wild-type CRP3 gene product is part of the general 3' --> 5' processing machinery.

  12. Targeted Sequencing Reveals Large-Scale Sequence Polymorphism in Maize Candidate Genes for Biomass Production and Composition.

    Directory of Open Access Journals (Sweden)

    Moses M Muraya

    Full Text Available A major goal of maize genomic research is to identify sequence polymorphisms responsible for phenotypic variation in traits of economic importance. Large-scale detection of sequence variation is critical for linking genes, or genomic regions, to phenotypes. However, due to its size and complexity, it remains expensive to generate whole genome sequences of sufficient coverage for divergent maize lines, even with access to next generation sequencing (NGS technology. Because methods involving reduction of genome complexity, such as genotyping-by-sequencing (GBS, assess only a limited fraction of sequence variation, targeted sequencing of selected genomic loci offers an attractive alternative. We therefore designed a sequence capture assay to target 29 Mb genomic regions and surveyed a total of 4,648 genes possibly affecting biomass production in 21 diverse inbred maize lines (7 flints, 14 dents. Captured and enriched genomic DNA was sequenced using the 454 NGS platform to 19.6-fold average depth coverage, and a broad evaluation of read alignment and variant calling methods was performed to select optimal procedures for variant discovery. Sequence alignment with the B73 reference and de novo assembly identified 383,145 putative single nucleotide polymorphisms (SNPs, of which 42,685 were non-synonymous alterations and 7,139 caused frameshifts. Presence/absence variation (PAV of genes was also detected. We found that substantial sequence variation exists among genomic regions targeted in this study, which was particularly evident within coding regions. This diversification has the potential to broaden functional diversity and generate phenotypic variation that may lead to new adaptations and the modification of important agronomic traits. Further, annotated SNPs identified here will serve as useful genetic tools and as candidates in searches for phenotype-altering DNA variation. In summary, we demonstrated that sequencing of captured DNA is a powerful

  13. Effects of chronic ascariasis and trichuriasis on cytokine production and gene expression in human blood: a cross-sectional study.

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    Miguel Reina Ortiz

    2011-06-01

    Full Text Available BACKGROUND: Chronic soil-transmitted helminth (STH infections are associated with effects on systemic immune responses that could be caused by alterations in immune homeostasis. To investigate this, we measured the impact in children of STH infections on cytokine responses and gene expression in unstimulated blood. METHODOLOGY/PRINCIPAL FINDINGS: Sixty children were classified as having chronic, light, or no STH infections. Peripheral blood mononuclear cells were cultured in medium for 5 days to measure cytokine accumulation. RNA was isolated from peripheral blood and gene expression analysed using microarrays. Different infection groups were compared for the purpose of analysis: STH infection (combined chronic and light vs. uninfected groups and chronic STH infection (chronic vs. combined light and uninfected groups. The chronic STH infection effect was associated with elevated production of GM-CSF (P=0.007, IL-2 (P=0.03, IL-5 (P=0.01, and IL-10 (P=0.01. Data reduction suggested that chronic infections were primarily associated with an immune phenotype characterized by elevated IL-5 and IL-10, typical of a modified Th2-like response. Chronic STH infections were associated with the up-regulation of genes associated with immune homeostasis (IDO, P=0.03; CCL23, P=0.008, HRK, P=0.005, down-regulation of microRNA hsa-let-7d (P=0.01 and differential regulation of several genes associated with granulocyte-mediated inflammation (IL-8, down-regulated, P=0.0002; RNASE2, up-regulated, P=0.009; RNASE3, up-regulated, p=0.03. CONCLUSIONS/SIGNIFICANCE: Chronic STH infections were associated with a cytokine response indicative of a modified Th2 response. There was evidence that STH infections were associated with a pattern of gene expression suggestive of the induction of homeostatic mechanisms, the differential expression of several inflammatory genes and the down-regulation of microRNA has-let-7d. Effects on immune homeostasis and the development of a

  14. In vitro production of bovine embryos: cumulus/granulosa cell gene expression patterns point to early atresia as beneficial for oocyte competence

    DEFF Research Database (Denmark)

    Mazzoni, Gianluca; Razza, Eduardo; Pedersen, Hanne S.

    2017-01-01

    In vitro production (IW) of bovine embryos has become widespread technology implemented in cattle breeding and production. Here, we review novel data on cumulus/granulosa cell gene expression, as determined by RNAseq on cellular material from pooled follicular fluids at the single animal level...

  15. Phylogenetic grouping and distribution of virulence genes in Escherichia coli along the production and supply chain of pork around Hubei, China.

    Science.gov (United States)

    Khan, Sher Bahadar; Zou, Geng; Cheng, Yu-Ting; Xiao, Ran; Li, Lu; Wu, Bin; Zhou, Rui

    2016-03-31

    Escherichia coli is an important foodborne zoonotic pathogen. A total of 285 strains of E. coli were isolated from the production and supply chain of pork in Hubei, China and characterized. Their phylogroups (A, B1, B2, and D) and virulence genes of public health importance become more and more diverse along the production and supply chain.

  16. New natural products isolated from Metarhizium robertsii ARSEF 23 by chemical screening and identification of the gene cluster through engineered biosynthesis in Aspergillus nidulans A1145.

    Science.gov (United States)

    Kato, Hiroki; Tsunematsu, Yuta; Yamamoto, Tsuyoshi; Namiki, Takuya; Kishimoto, Shinji; Noguchi, Hiroshi; Watanabe, Kenji

    2016-07-01

    To rapidly identify novel natural products and their associated biosynthetic genes from underutilized and genetically difficult-to-manipulate microbes, we developed a method that uses (1) chemical screening to isolate novel microbial secondary metabolites, (2) bioinformatic analyses to identify a potential biosynthetic gene cluster and (3) heterologous expression of the genes in a convenient host to confirm the identity of the gene cluster and the proposed biosynthetic mechanism. The chemical screen was achieved by searching known natural product databases with data from liquid chromatographic and high-resolution mass spectrometric analyses collected on the extract from a target microbe culture. Using this method, we were able to isolate two new meroterpenes, subglutinols C (1) and D (2), from an entomopathogenic filamentous fungus Metarhizium robertsii ARSEF 23. Bioinformatics analysis of the genome allowed us to identify a gene cluster likely to be responsible for the formation of subglutinols. Heterologous expression of three genes from the gene cluster encoding a polyketide synthase, a prenyltransferase and a geranylgeranyl pyrophosphate synthase in Aspergillus nidulans A1145 afforded an α-pyrone-fused uncyclized diterpene, the expected intermediate of the subglutinol biosynthesis, thereby confirming the gene cluster to be responsible for the subglutinol biosynthesis. These results indicate the usefulness of our methodology in isolating new natural products and identifying their associated biosynthetic gene cluster from microbes that are not amenable to genetic manipulation. Our method should facilitate the natural product discovery efforts by expediting the identification of new secondary metabolites and their associated biosynthetic genes from a wider source of microbes.

  17. Cloning and Sequence Analysis of the Full-length cDNA of a Novel yp05 Gene Associated With Citrinin Production in Monascus aurantiacus

    Institute of Scientific and Technical Information of China (English)

    YON-GHUA XIONG; YANG XU; WEI-HUA LAI; YAN-PIN LI; HUA WEI

    2007-01-01

    Objective To obtain the full-length cDNA of a novel gene (named yp05) associated with citrinin production-related genes in Monascus aurantiacus. Methods Total RNA was extracted from mycelium, 3' and 5' cDNA end of yp05 gene was amplified using smartTM trace cDNA amplification kit, and the full-length cDNA of a novel gene (named yp05) was obtained from the electronic assembly of 3'-RACE and 5'- RACE products. Results This yp05 gene was 787 bp including a 597 bp open reading frame (ORF) and encoded a deduced protein with 199 amino acid residues, and the amino acid sequence of this protein was found similar with the sequences of many fungal manganese-superoxide dismutases in the GenBank with the aid of BLASTp. The transcription of yp05 gene in Monascus strains was analyzed with the aid of Northern blotting. The transcription of yp05 gene was only detected in Monascus strains, provided that citrinin was produced. Conclusion The transcription of yp05 gene belongs to differential expression genes of citrinin yielded from Monascus and has no correlation with the biosynthesis pathway of red pigments.

  18. Phenotypes and gene expression profiles of Saccharopolyspora erythraea rifampicin-resistant (rif mutants affected in erythromycin production

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    Bicciato Silvio

    2009-03-01

    Full Text Available Abstract Background There is evidence from previous works that bacterial secondary metabolism may be stimulated by genetic manipulation of RNA polymerase (RNAP. In this study we have used rifampicin selection as a strategy to genetically improve the erythromycin producer Saccharopolyspora erythraea. Results Spontaneous rifampicin-resistant (rif mutants were isolated from the parental strain NRRL2338 and two rif mutations mapping within rpoB, S444F and Q426R, were characterized. With respect to the parental strain, S444F mutants exhibited higher respiratory performance and up to four-fold higher final erythromycin yields; in contrast, Q426R mutants were slow-growing, developmental-defective and severely impaired in erythromycin production. DNA microarray analysis demonstrated that these rif mutations deeply changed the transcriptional profile of S. erythraea. The expression of genes coding for key enzymes of carbon (and energy and nitrogen central metabolism was dramatically altered in turn affecting the flux of metabolites through erythromycin feeder pathways. In particular, the valine catabolic pathway that supplies propionyl-CoA for biosynthesis of the erythromycin precursor 6-deoxyerythronolide B was strongly up-regulated in the S444F mutants, while the expression of the biosynthetic gene cluster of erythromycin (ery was not significantly affected. In contrast, the ery cluster was down-regulated ( Conclusion Rifampicin selection is a simple and reliable tool to investigate novel links between primary and secondary metabolism and morphological differentiation in S. erythraea and to improve erythromycin production. At the same time genome-wide analysis of expression profiles using DNA microarrays allowed information to be gained about the mechanisms underlying the stimulatory/inhibitory effects of the rif mutations on erythromycin production.

  19. Nitrile-synthesizing enzyme: Gene cloning, overexpression and application for the production of useful compounds.

    Science.gov (United States)

    Kumano, Takuto; Takizawa, Yuko; Shimizu, Sakayu; Kobayashi, Michihiko

    2016-09-12

    One of the nitrile-synthesizing enzymes, β-cyano-L-alanine synthase, catalyzes β-cyano-L-alanine (β-CNAla) from potassium cyanide and O-acetyl-L-serine or L-cysteine. We have identified this enzyme from Pseudomonas ovalis No. 111. In this study, we cloned the β-CNAla synthase gene and expressed it in Escherichia coli and Rhodococcus rhodochrous. Furthermore, we carried out co-expression of β-CNAla synthase with nitrilase or nitrile hydratases in order to synthesize aspartic acid and asparagine from KCN and O-acetyl-L-serine. This strategy can be used for the synthesis of labeled amino acids by using a carbon-labeled KCN as a substrate, resulting in an application for positron emission tomography.

  20. In silico method for modelling metabolism and gene product expression at genome scale

    Energy Technology Data Exchange (ETDEWEB)

    Lerman, Joshua A.; Hyduke, Daniel R.; Latif, Haythem; Portnoy, Vasiliy A.; Lewis, Nathan E.; Orth, Jeffrey D.; Rutledge, Alexandra C.; Smith, Richard D.; Adkins, Joshua N.; Zengler, Karsten; Palsson, Bernard O.

    2012-07-03

    Transcription and translation use raw materials and energy generated metabolically to create the macromolecular machinery responsible for all cellular functions, including metabolism. A biochemically accurate model of molecular biology and metabolism will facilitate comprehensive and quantitative computations of an organism's molecular constitution as a function of genetic and environmental parameters. Here we formulate a model of metabolism and macromolecular expression. Prototyping it using the simple microorganism Thermotoga maritima, we show our model accurately simulates variations in cellular composition and gene expression. Moreover, through in silico comparative transcriptomics, the model allows the discovery of new regulons and improving the genome and transcription unit annotations. Our method presents a framework for investigating molecular biology and cellular physiology in silico and may allow quantitative interpretation of multi-omics data sets in the context of an integrated biochemical description of an organism.

  1. Effect of Co-overexpression of Nisin Key Genes on Nisin Production Improvement in Lactococcus lactis LS01.

    Science.gov (United States)

    Ni, Zhi-Jian; Zhang, Xiao-Yuan; Liu, Fei; Wang, Miao; Hao, Rong-Hua; Ling, Pei-Xue; Zhu, Xi-Qiang

    2017-06-01

    Nisin is a small antimicrobial peptide produced by several subset strains of Lactococcus lactis. To improve nisin yield in the producer L. lactis LS01, we proposed a successive fusion of nisA with nisRK and nisFEG into a single shuttle expression vector pMG36e under the control of