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Analysis of the gene lmbX included propylproline biosynthesis
Smutná, Yvona ; Najmanová, Lucie (referee)
Analysis of the gene lmbX included propylproline biosynthesis Abstract Lincomycin and its derivates are potent antibiotics used in human and veterinary medicine, they are antibiotics exibiting biological activity against Gram-positive bacteria. Lincomycin molecule is composed of two amide-bonded subunits, methylthiolincosamide and propylproline. The aim of the study was to assign the gene lmbX to the propylproline biosynthesis based on gene inactivation experiments. The gene lmbX was inactivated by help of REDIRECT technology: PCR targeting system in Streptomyces coelicolor. The respective S. lincolnensis inactivants were checked for lincomycin production by means of biological test and UPLC analysis of their fermentation broth and then exploited in feeding experiments. It was found, that inactivation of the lmbX gene caused suppression of the lincomycin production which was restored upon PPL feeding therefore the respective gene was assigned to reaction of PPL branch of LM biosynthesis.
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Preparation and characterization of LmbX protein involved in lincomycin biosynthesis
Jiráčková, Petra ; Janata, Jiří (advisor) ; Janderová, Blanka (referee)
Lincomycin is an antibiotic used in clinical praxis. It is produced by Streptomyces lincolnensis. Lincomycin is composed of an amino-sugar and an amino-acid moiety linked by an amide bond. The amino-acid precursor is propylproline (PPL), whose biosynthesis undergoes the pathway derived from tyrosine. The modified PPL biosynthesis pathway was also discovered in pyrrolobenzodiazepines (PBD) and hormaomycin. In the biosynthesis of PBD the PPL precursor is further modified by reactions catalysed by specific enzymes missing in the biosynthesis of lincomycin. The genes encoding these enzymes could be transferred to the lincomycin biosynthetic gene cluster. In this way we could get producers of hybrid antibiotics with better properties and even antimalaric effects. Six enzymes participate in PPL biosynthesis, which are encoded in the lincomycin biosynthetic gene cluster. The first two reactions of PPL biosynthesis pathway are proven, therefore, this work focuses on the third reaction that is supposed to be catalysed by protein LmbX according to literature. The proposed function of LmbX is a hydrolysis of C-C bond. However, LmbX belongs to the protein family of isomerases by sequence homology. The protein LmbX was overproduced in this work and its activity was tested in the presence of the expected...
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Analysis of the gene lmbX included propylproline biosynthesis
Smutná, Yvona ; Najmanová, Lucie (referee)
Analysis of the gene lmbX included propylproline biosynthesis Abstract Lincomycin and its derivates are potent antibiotics used in human and veterinary medicine, they are antibiotics exibiting biological activity against Gram-positive bacteria. Lincomycin molecule is composed of two amide-bonded subunits, methylthiolincosamide and propylproline. The aim of the study was to assign the gene lmbX to the propylproline biosynthesis based on gene inactivation experiments. The gene lmbX was inactivated by help of REDIRECT technology: PCR targeting system in Streptomyces coelicolor. The respective S. lincolnensis inactivants were checked for lincomycin production by means of biological test and UPLC analysis of their fermentation broth and then exploited in feeding experiments. It was found, that inactivation of the lmbX gene caused suppression of the lincomycin production which was restored upon PPL feeding therefore the respective gene was assigned to reaction of PPL branch of LM biosynthesis.
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