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A.s. Ball - One of the best experts on this subject based on the ideXlab platform.

  • Effect of inoculation of herbage prior to ensiling with Streptomyces Achromogenes ISP 5028 on chemical composition of silage
    Animal Feed Science and Technology, 2001
    Co-Authors: J. Hill, G.q. Xiao, A.s. Ball
    Abstract:

    Enzymes derived from bacteria and fungi have been used as additives in silage production. Increasing attention has been given to the use of cell-wall degrading enzymes such as cellulases, hemicellulases and peroxidases. However, little information has been published on the potential role of actinomycetes in silage production. The experiment reported in this paper examined the changes in chemical composition and predicted nutritive value of herbage inoculated with Streptomyces Achromogenes ISP 5028 during 60 days of ensiling. Changes in chemical composition and nutritive value of herbage were examined after 1, 2, 3, 5, 10, 30 and 60 days ensiling. Colonisation of inoculated silage by S. Achromogenes ISP 5028 occurred rapidly and after 30 days of ensiling the difference in viable spores was 1000-fold between the control and treated silages (P 0.05) from the cell wall. The changes in the composition of the cell wall facilitated an increase in the concentration of WSC (P

  • effect of inoculation of herbage prior to ensiling with Streptomyces Achromogenes isp 5028 on chemical composition of silage
    Animal Feed Science and Technology, 2001
    Co-Authors: J. Hill, G.q. Xiao, A.s. Ball
    Abstract:

    Enzymes derived from bacteria and fungi have been used as additives in silage production. Increasing attention has been given to the use of cell-wall degrading enzymes such as cellulases, hemicellulases and peroxidases. However, little information has been published on the potential role of actinomycetes in silage production. The experiment reported in this paper examined the changes in chemical composition and predicted nutritive value of herbage inoculated with Streptomyces Achromogenes ISP 5028 during 60 days of ensiling. Changes in chemical composition and nutritive value of herbage were examined after 1, 2, 3, 5, 10, 30 and 60 days ensiling. Colonisation of inoculated silage by S. Achromogenes ISP 5028 occurred rapidly and after 30 days of ensiling the difference in viable spores was 1000-fold between the control and treated silages (P 0.05) from the cell wall. The changes in the composition of the cell wall facilitated an increase in the concentration of WSC (P<0.001), thus allowing greater concentrations of lactic (P<0.001) and acetic (P<0.01) acids to be formed. Elevated concentrations of various isomeric forms of butyric and valeric acid were also observed in the treated silage compared to the control. Inoculation of herbage with S. Achromogenes ISP 5028 prior to ensiling altered the chemical and nutritive composition of silage, however it is not known whether the risks associated with other actinomycetes (respiratory disorders and toxin release) apply to the test organism in these experiments.

J. Hill - One of the best experts on this subject based on the ideXlab platform.

  • Effect of inoculation of herbage prior to ensiling with Streptomyces Achromogenes ISP 5028 on chemical composition of silage
    Animal Feed Science and Technology, 2001
    Co-Authors: J. Hill, G.q. Xiao, A.s. Ball
    Abstract:

    Enzymes derived from bacteria and fungi have been used as additives in silage production. Increasing attention has been given to the use of cell-wall degrading enzymes such as cellulases, hemicellulases and peroxidases. However, little information has been published on the potential role of actinomycetes in silage production. The experiment reported in this paper examined the changes in chemical composition and predicted nutritive value of herbage inoculated with Streptomyces Achromogenes ISP 5028 during 60 days of ensiling. Changes in chemical composition and nutritive value of herbage were examined after 1, 2, 3, 5, 10, 30 and 60 days ensiling. Colonisation of inoculated silage by S. Achromogenes ISP 5028 occurred rapidly and after 30 days of ensiling the difference in viable spores was 1000-fold between the control and treated silages (P 0.05) from the cell wall. The changes in the composition of the cell wall facilitated an increase in the concentration of WSC (P

  • effect of inoculation of herbage prior to ensiling with Streptomyces Achromogenes isp 5028 on chemical composition of silage
    Animal Feed Science and Technology, 2001
    Co-Authors: J. Hill, G.q. Xiao, A.s. Ball
    Abstract:

    Enzymes derived from bacteria and fungi have been used as additives in silage production. Increasing attention has been given to the use of cell-wall degrading enzymes such as cellulases, hemicellulases and peroxidases. However, little information has been published on the potential role of actinomycetes in silage production. The experiment reported in this paper examined the changes in chemical composition and predicted nutritive value of herbage inoculated with Streptomyces Achromogenes ISP 5028 during 60 days of ensiling. Changes in chemical composition and nutritive value of herbage were examined after 1, 2, 3, 5, 10, 30 and 60 days ensiling. Colonisation of inoculated silage by S. Achromogenes ISP 5028 occurred rapidly and after 30 days of ensiling the difference in viable spores was 1000-fold between the control and treated silages (P 0.05) from the cell wall. The changes in the composition of the cell wall facilitated an increase in the concentration of WSC (P<0.001), thus allowing greater concentrations of lactic (P<0.001) and acetic (P<0.01) acids to be formed. Elevated concentrations of various isomeric forms of butyric and valeric acid were also observed in the treated silage compared to the control. Inoculation of herbage with S. Achromogenes ISP 5028 prior to ensiling altered the chemical and nutritive composition of silage, however it is not known whether the risks associated with other actinomycetes (respiratory disorders and toxin release) apply to the test organism in these experiments.

Chun-gyu Kim - One of the best experts on this subject based on the ideXlab platform.

  • mediation of rubradirin resistance by abc transporters rubt1 from Streptomyces Achromogenes var rubradiris nrrl3061
    Journal of Microbiology and Biotechnology, 2006
    Co-Authors: Janardan Lamichhane, Kwangkyoung Liou, Hei Chan Lee, Chun-gyu Kim, Jae Kyung Sohng
    Abstract:

    The rubradirin biosynthetic gene cluster harbors 58 ORFs within a 105.6-kb sequence, which includes all of the genes responsible for the synthesis of rubradirin, as well as the primary genes relevant to regulatory, resistance, and transport functions. This gene cluster also harbors a resistance-mediating ABC transporter, RubTl, which is located at the most upstream position in the cluster. In the present study, RubTl was expressed heterologously in E. coli, and the resistance affinity of RubTl 1 was determined by an antibacterial activity test, as well as by HPLC and ESI-MS analyses. Evidence clearly demonstrates that RubTl mediates rubradirin resistance as an ABC transporter.

  • Functional identification of rub52 gene involved in the biosynthesis of rubradirin
    Biotechnology Letters, 2003
    Co-Authors: Jyoti Maharjan, Kwangkyoung Liou, Hei Chan Lee, Chun-gyu Kim, Jung-joon Lee, Jin-cheol Yoo, Jae Kyung Sohng
    Abstract:

    An open reading frame, rub52 , has been identified as a gene encoding thymidine diphospho-glucose 2,3-dehydratase by sequence analysis of the rubradirin biosynthetic gene cluster of Streptomyces Achromogenes var. rubradiris NRRL3061.The gene codes for a protein consisting of 458 amino acids with calculated molecular mass of 50 862 Da. The gene was amplified and heterologously expressed in Escherichia coli as a soluble His-tagged fusion protein. C-2 deoxygenation functionality of thymidine diphospho-4-keto-6-deoxyglucose was assigned to the rub52 gene product from in vitro enzyme assay.

  • Identification of a gene cluster of biosynthetic genes of rubradirin substructures in S. Achromogenes var. rubradiris NRRL3061.
    Molecules and cells, 1997
    Co-Authors: Jae Kyung Sohng, Jung-joon Lee, Chun-gyu Kim
    Abstract:

    Rubradirin, an ansamycin antibiotic has been purified from Streptomyces Achromogenes var. rubradiris NRRL3061. It consists of four distinct structural moieties, rubransarol, 3-amino-4-hydroxy-coumarin, dihydroxydipicolinic acid, and 2,6-dideoxynitrosugar (DNS). Polymerase chain reaction (PCR) primers were designed based on consensus sequences of dTDP-D-glucose 4,6-dehydratase, one of enzymes involved in the biosynthesis of 2,6-dideoxysugar. A PCR product was obtained from S. Achromogenes var. rubradiris. Hybridization of the PCR product to a cosmid library constructed from S. Achromogenes genomic DNA has led to the identification of three unlinked regions of DNA. One of three kinds of cosmid clones contains homologues of dTDP-D-glucose 4,6-dehydratase, 3-amino-5-hydroxybenzoic acid (AHBA) synthase, and eryA genes. The size of the gene homologous to eryA is 30 kb, and the AHBA synthase gene homologue resides between the eryA homologous genes. A gene cluster of rubransarol and 2,6-dideoxynitrosugar is around 50 kb. Sequencing of the PCR product from the AHBA synthase gene homologue isolated from S. Achromogenes revealed 85% amino acid sequence homology (73/86) with the AHBA synthase from a rifamycin-producer. dTDP-D-glucose 4,6-dehydratase gene homologue was subcloned from one of the isolated cosmid clones and sequenced. It showed 65% homology (43/66) with dTDP-D-glucose 4,6-dehydratase from a streptomycin-producer.

  • Identification of a gene cluster of biosynthetic genes of rubradirin substructures in S. Achromogenes var. rubradiris NRRL3061
    Springer Verlag (Germany), 1997
    Co-Authors: Jae Kyung Sohng, Jung-joon Lee, Chun-gyu Kim
    Abstract:

    Rubradirin, an ansamycin antibiotic has been purified from Streptomyces Achromogenes var. rubradiris NRRL3061. It consists of four distinct structural moieties, rubransarol, 3-amino-4-hydroxy-coumarin, dihydroxydipicolinic acid, and 2,6-dideoxynitrosugar (DNS). Polymerase chain reaction (PCR) primers were designed based on consensus sequences of dTDP-D-glucose 4,6-dehydratase, one of enzymes involved in the biosynthesis of 2,6-dideoxysugar. A PCR product was obtained from S. Achromogenes var. rubradiris. Hybridization of the PCR product to a cosmid library constructed from S. Achromogenes genomic DNA has led to the identification of three unlinked regions of DNA. One of three kinds of cosmid clones contains homologues of dTDP-D-glucose 4,6-dehydratase, 3-amino-5-hydroxybenzoic acid (AHBA) synthase, and eryA genes. The size of the gene homologous to eryA is 30 kb, and the AHBA synthase gene homologue resides between the eryA homologous genes. A gene cluster of rubransarol and 2,6-dideoxynitrosugar is around 50 kb. Sequencing of the PCR product from the AHBA synthase gene homologue isolated from S. Achromogenes revealed 85% amino acid sequence homology (73/86) with the AHBA synthase from a rifamycin-producer. dTDP-D-glucose 4,6-dehydratase gene homologue was subcloned from one of the isolated cosmid clones and sequenced. It showed 65% homology (43/66) with dTDP-D-glucose 4,6-dehydratase from a streptomycin-producer.ope

Jae Kyung Sohng - One of the best experts on this subject based on the ideXlab platform.

  • Functional Characterization of Ketoreductase (rubN6) and Aminotransferase (rubN4) Genes in the Gene Cluster of Streptomyces Achromogenes var. rubradiris
    Biotechnology Letters, 2006
    Co-Authors: Janardan Lamichhane, Kwangkyoung Liou, Jae Kyung Sohng
    Abstract:

    ORF’s for rubN6 and rubN4 have been annotated as thymidine diphosphate glucose 4-ketoreductase and thymidine diphosphate glucose 3-aminotransferase by sequence analysis of the rubradirin biosynthetic gene cluster cloned from Streptomyces Achromogenes var. rubradiris NRRL 3061. Both ORFs were heterologously expressed in Escherichia coli as His-tagged fusion proteins. The functionalities of TDP-glucose 4-ketoreductase and TDP-glucose 3-aminotransferase were verified by in vitro enzyme assay, and a biosynthetic pathway for TDP- d -rubranitrose is proposed.

  • mediation of rubradirin resistance by abc transporters rubt1 from Streptomyces Achromogenes var rubradiris nrrl3061
    Journal of Microbiology and Biotechnology, 2006
    Co-Authors: Janardan Lamichhane, Kwangkyoung Liou, Hei Chan Lee, Chun-gyu Kim, Jae Kyung Sohng
    Abstract:

    The rubradirin biosynthetic gene cluster harbors 58 ORFs within a 105.6-kb sequence, which includes all of the genes responsible for the synthesis of rubradirin, as well as the primary genes relevant to regulatory, resistance, and transport functions. This gene cluster also harbors a resistance-mediating ABC transporter, RubTl, which is located at the most upstream position in the cluster. In the present study, RubTl was expressed heterologously in E. coli, and the resistance affinity of RubTl 1 was determined by an antibacterial activity test, as well as by HPLC and ESI-MS analyses. Evidence clearly demonstrates that RubTl mediates rubradirin resistance as an ABC transporter.

  • Functional identification of rub52 gene involved in the biosynthesis of rubradirin
    Biotechnology Letters, 2003
    Co-Authors: Jyoti Maharjan, Kwangkyoung Liou, Hei Chan Lee, Chun-gyu Kim, Jung-joon Lee, Jin-cheol Yoo, Jae Kyung Sohng
    Abstract:

    An open reading frame, rub52 , has been identified as a gene encoding thymidine diphospho-glucose 2,3-dehydratase by sequence analysis of the rubradirin biosynthetic gene cluster of Streptomyces Achromogenes var. rubradiris NRRL3061.The gene codes for a protein consisting of 458 amino acids with calculated molecular mass of 50 862 Da. The gene was amplified and heterologously expressed in Escherichia coli as a soluble His-tagged fusion protein. C-2 deoxygenation functionality of thymidine diphospho-4-keto-6-deoxyglucose was assigned to the rub52 gene product from in vitro enzyme assay.

  • Identification of a gene cluster of biosynthetic genes of rubradirin substructures in S. Achromogenes var. rubradiris NRRL3061.
    Molecules and cells, 1997
    Co-Authors: Jae Kyung Sohng, Jung-joon Lee, Chun-gyu Kim
    Abstract:

    Rubradirin, an ansamycin antibiotic has been purified from Streptomyces Achromogenes var. rubradiris NRRL3061. It consists of four distinct structural moieties, rubransarol, 3-amino-4-hydroxy-coumarin, dihydroxydipicolinic acid, and 2,6-dideoxynitrosugar (DNS). Polymerase chain reaction (PCR) primers were designed based on consensus sequences of dTDP-D-glucose 4,6-dehydratase, one of enzymes involved in the biosynthesis of 2,6-dideoxysugar. A PCR product was obtained from S. Achromogenes var. rubradiris. Hybridization of the PCR product to a cosmid library constructed from S. Achromogenes genomic DNA has led to the identification of three unlinked regions of DNA. One of three kinds of cosmid clones contains homologues of dTDP-D-glucose 4,6-dehydratase, 3-amino-5-hydroxybenzoic acid (AHBA) synthase, and eryA genes. The size of the gene homologous to eryA is 30 kb, and the AHBA synthase gene homologue resides between the eryA homologous genes. A gene cluster of rubransarol and 2,6-dideoxynitrosugar is around 50 kb. Sequencing of the PCR product from the AHBA synthase gene homologue isolated from S. Achromogenes revealed 85% amino acid sequence homology (73/86) with the AHBA synthase from a rifamycin-producer. dTDP-D-glucose 4,6-dehydratase gene homologue was subcloned from one of the isolated cosmid clones and sequenced. It showed 65% homology (43/66) with dTDP-D-glucose 4,6-dehydratase from a streptomycin-producer.

  • Identification of a gene cluster of biosynthetic genes of rubradirin substructures in S. Achromogenes var. rubradiris NRRL3061
    Springer Verlag (Germany), 1997
    Co-Authors: Jae Kyung Sohng, Jung-joon Lee, Chun-gyu Kim
    Abstract:

    Rubradirin, an ansamycin antibiotic has been purified from Streptomyces Achromogenes var. rubradiris NRRL3061. It consists of four distinct structural moieties, rubransarol, 3-amino-4-hydroxy-coumarin, dihydroxydipicolinic acid, and 2,6-dideoxynitrosugar (DNS). Polymerase chain reaction (PCR) primers were designed based on consensus sequences of dTDP-D-glucose 4,6-dehydratase, one of enzymes involved in the biosynthesis of 2,6-dideoxysugar. A PCR product was obtained from S. Achromogenes var. rubradiris. Hybridization of the PCR product to a cosmid library constructed from S. Achromogenes genomic DNA has led to the identification of three unlinked regions of DNA. One of three kinds of cosmid clones contains homologues of dTDP-D-glucose 4,6-dehydratase, 3-amino-5-hydroxybenzoic acid (AHBA) synthase, and eryA genes. The size of the gene homologous to eryA is 30 kb, and the AHBA synthase gene homologue resides between the eryA homologous genes. A gene cluster of rubransarol and 2,6-dideoxynitrosugar is around 50 kb. Sequencing of the PCR product from the AHBA synthase gene homologue isolated from S. Achromogenes revealed 85% amino acid sequence homology (73/86) with the AHBA synthase from a rifamycin-producer. dTDP-D-glucose 4,6-dehydratase gene homologue was subcloned from one of the isolated cosmid clones and sequenced. It showed 65% homology (43/66) with dTDP-D-glucose 4,6-dehydratase from a streptomycin-producer.ope

Anna J. Podhajska - One of the best experts on this subject based on the ideXlab platform.