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Preparation of genetically manipulated producers of hybrid manumycins
Krýslová, Dita ; Petříčková, Kateřina (advisor) ; Doubravová, Linda (referee)
Streptomyces are one of the most prolific producers of various secondary metabolites. Manumycin antibiotics represent an important class of these compounds. They belong to a big class of polyketide metabolites. While their antibiotic effect is not very significant, their other biological properties have a big potential in the treatment of inflammations, tumors, etc. They are characterized by two short polyketide chains, which are attached to a central subunit. At the end of the lower polyketide chain, a C5N cyclic unit is frequently attached. This thesis originates from the colabomycin E, an antibiotic, which was discovered by our team. This antibiotic is a new member of manumycin-type metabolites and is produced by Streptomyces aureus SOK1/5-04 strain. Previous studies on the function of individual genes in the biosynthetic gene cluster of colabomycin E inspired us to consider editing of the current biological activity of colabomycin E by replacement of the C5N unit with another, structurally similar bioactive subunit. Due to high structural similarity, we have selected 4,7- dihydroxycoumarin unit of novobiocin, an aminocoumarin-type metabolite produced also by Streptomyces. The 4,7-dihydroxycoumarin unit is pharmacophore with a cancerostatic activity. We expected that the cancerostatic activity...
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Analysis of the biosynthetic gene cluster encoding biosynthesis of the manumycin antibiotic U-62162, and the ways of its modification.
Urbanová, Daniela ; Petříček, Miroslav (advisor) ; Schierová, Michaela (referee)
Streptomyces is the largest antibiotic-producing genus in the microbial world. Manumycin-type antibiotics are a small group of its metabolites. Their antibiotic activities are not very important but they show biological properties which can be potencially used e. g. to treat inflammation, cancer or Alzheimer's disease. The structure of manumycin compounds is formed by a central unit with connected upper and lower polyketide chain. The lower chain is mostly terminated by so called C5N unit. The substance U-62162 produced by the strain Streptomyces verdensis differs significantly from the other members of the manumycin-type metabolites in the structure of the lower chain which is fully saturated and lacking the C5N unit. The U-62162 biosynthetic gene cluster was sequenced and functions of identified open reading frames were deduced. Heterologous expressions of the cluster showed some genes reguired for the biosynthesis of the upper chain to be encoded on a different part of the chromosome. The insertional inactivation of the vrdER gene confirmed the enoylreductase to be responsible for the saturation of the lower chain. DSBA oxidoreductase, which gene is located at the edge of the cluster, is probably not involved in the biosynthesis. The insertion of genes for the biosynthesis of the C5N unit did...
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Analysis of the biosynthetic gene cluster encoding biosynthesis of the manumycin antibiotic U-62162, and the ways of its modification.
Urbanová, Daniela ; Petříček, Miroslav (advisor) ; Schierová, Michaela (referee)
Streptomyces is the largest antibiotic-producing genus in the microbial world. Manumycin-type antibiotics are a small group of its metabolites. Their antibiotic activities are not very important but they show biological properties which can be potencially used e. g. to treat inflammation, cancer or Alzheimer's disease. The structure of manumycin compounds is formed by a central unit with connected upper and lower polyketide chain. The lower chain is mostly terminated by so called C5N unit. The substance U-62162 produced by the strain Streptomyces verdensis differs significantly from the other members of the manumycin-type metabolites in the structure of the lower chain which is fully saturated and lacking the C5N unit. The U-62162 biosynthetic gene cluster was sequenced and functions of identified open reading frames were deduced. Heterologous expressions of the cluster showed some genes reguired for the biosynthesis of the upper chain to be encoded on a different part of the chromosome. The insertional inactivation of the vrdER gene confirmed the enoylreductase to be responsible for the saturation of the lower chain. DSBA oxidoreductase, which gene is located at the edge of the cluster, is probably not involved in the biosynthesis. The insertion of genes for the biosynthesis of the C5N unit did...
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