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Updated: May 11, 2026
08:48
Development of a Backbone Cyclic Peptide Library as Potential Antiparasitic Therapeutics Using Microwave Irradiation
Published on: January 26, 2016
The posttranslational modification cascade to the thiopeptide berninamycin generates linear forms and altered
Steven J Malcolmson1, Travis S Young, J Graham Ruby
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
Summary
Researchers explored the biosynthesis of berninamycin, a unique thiopeptide antibiotic. They identified its gene cluster and studied its posttranslational modifications, revealing insights into its unusual macrocyclic structure.
Area of Science:
- Microbiology
- Biochemistry
- Molecular Biology
Background:
- Berninamycin is a pyridine-containing thiopeptide antibiotic.
- It features a unique 2-oxazolyl-3-thiazolyl-pyridine core within a 35-atom macrocycle.
- This structure differs from typical thiopeptide cores and macrocycle sizes.
Purpose of the Study:
- To clone and characterize the berninamycin biosynthetic gene cluster.
- To investigate the posttranslational modifications of berninamycin preproteins.
- To understand the formation of its unique macrocyclic structure.
Main Methods:
- Cloning of the 11-gene berninamycin cluster from Streptomyces bernensis.
- Heterologous expression in Streptomyces lividans and Streptomyces venezuelae.
- Analysis of prepeptide processing and scaffold variants.
Main Results:
- Successful cloning and heterologous expression of the berninamycin gene cluster.
- Identification of macrocyclic compounds and linear variants during posttranslational maturation.
- Observation of a variant berninamycin skeleton with a methyloxazoline in S. venezuelae.
Conclusions:
- The study elucidates the genetic basis for berninamycin biosynthesis.
- It highlights the complex posttranslational modifications involved in forming its unique structure.
- Heterologous expression provides a platform for studying thiopeptide antibiotic variations.
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