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Showing 1 to 13 of 13 for “"lacticin 481"”.
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Investigation of the Lacticin 481 Synthetase and Its Substrate LctA in the Production of the Antibiotic Lacticin 481
… are generated by one bifunctional LanM enzyme. Lacticin 481 synthetase (LctM) catalyzes the post-translational modifications required for the generation of the lantibiotic lacticin 481. Previous studies in our laboratory revealed the protein responsible for the creation of the intricate …
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Biosynthesis of the Polycyclic Antimicrobial Peptides Lacticin 481, Haloduracin, and Cinnamycin
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2009.
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Investigation of the Enzymes Involved in Lantibiotic Biosynthesis: Lacticin 481 and Haloduracin
… for achievement of full biological activity. In lacticin 481 maturation, this peptide cleavage reaction is performed by the N-terminal protease domain of the lacticin 481 transporter, LctT. The activity of the protease domain of LctT was reconstituted in vitro and its substrate specificity was …
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Mechanistic Investigations of Dehydration of Lacticin 481 Synthetase and Exploring Its Biochemical Applications
Developing a selective labeling method for peptides/proteins is of great interest in numerous research areas. In order to explore this idea, a strategy was developed through which an N-terminal ketone was introduced by using the LctA-LctM modification system. Finally, analysis of phosphorylated …
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Investigations of the Substrate Specificity of Lacticin 481 Synthetase and Utilization in Peptide Engineering Applications
… Lastly, the role of the leader peptide in lacticin 481 biosynthesis was investigated. Surprisingly, the leader peptide was not required for dehydration activity of LctM, although it greatly enhanced the catalytic efficiency of LctM.
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From Peptide Precursors to Lanthionine -Containing Peptide Antibiotics Using the First Isolated and Active Lacticin 481 Synthetase: Mechanistic Studies and Peptide Engineering
… unsuccessful. As a result, the biosynthesis of lacticin 481 which employs one single modification enzyme presumably responsible for both dehydration and cyclization was investigated. Both the modification enzyme LctM and the substrate LctA were cloned and purified to homogeneity. The in vitro …
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Chemical and chemoenzymatic syntheses of lantibiotics and other bioactive cyclic peptides
… of an engineered biosynthetic enzyme involved in lacticin 481 maturation was reconstituted in vitro and used to produce a panel of lacticin 481 analogues from synthetic precursor peptides, several of which possessed improved antibacterial potency. This enhanced potency was correlated with improved …
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Mechanistic studies of class II lanthipeptide synthetases and yeast surface display of lanthipeptide leader peptides
… peptide and LctA (the precursor peptide for lacticin 481) core peptide was constructed and co-expressed with ProcM in Escherichia coli. ProcM dehydrated this chimeric peptide up to 5-fold (WT lacticin 481 is dehydrated 4-fold), and also catalyzed the formation of 2~3 rings (WT lacticin 481 …
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Biosynthesis and mode of action of ribosomally synthesized and post-translationally modified antimicrobial peptides
… 3, enabled the production of fully-modified lacticin 481 products with proteinogenic and non-proteinogenic amino acid substitutions. A number of lacticin 481 analogues were prepared and their antimicrobial activity and ability to bind lipid II was assessed. Moreover, site-directed mutagenesis …
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Investigations of the Mechanism and Substrate Scope of the Enzymes Involved in Lantibiotic Biosynthesis
… The successful in vitro reconstitution of the lacticin 481 synthetase, LctM, led to preliminary investigations of its low substrate specificity. In this thesis the substrate specificity of LctM was tested further with non-proteinogenic amino acids. The effect of D-amino acids in the truncated …
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Mechanistic Investigations of Cyclase Enzymes Involved in Lantibiotic Biosynthesis
… using LctM, the LanM protein involved in lacticin 481 biosynthesis. Cysteine and histidine mutants have been generated and analyzed to determine if eliminating the protein's ability to bind zinc leads to a loss in cyclization activity. Results from these experiments implicate Cys836 and …
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Expanding the structural diversity of the RiPP class of natural products
… I lantibiotic nisin and the class II lantibiotic lacticin 481 using amber stop codon technology.
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New chemical and biosynthetic methodologies for the study of lanthipeptides
Recent genome sequencing efforts have revealed that a common biosynthetic route to peptide natural products involves ribosomally synthesized and posttranslationally modified peptides (RiPPs). One of the largest classes of RiPPs is the lanthionine-containing peptides (lanthipeptides), which are …