Stoichiometry and structure of a lantibiotic maturation complex
Jens Reiners1, André Abts1, Rebecca Clemens1
1Institute of Biochemistry, Heinrich-Heine-University Duesseldorf, Universitaetsstraße 1, 40225 Duesseldorf, Germany.
Scientific Reports
|February 8, 2017
Summary
Researchers studied the assembly of the nisin modification complex (NisBC). This complex, crucial for lantibiotic maturation, forms only with its substrate, prenisin, revealing its structure and stoichiometry.
Area of Science:
- Microbiology
- Biochemistry
- Structural Biology
Background:
- Lantibiotics are ribosomally synthesized antimicrobial peptides from Gram-positive bacteria.
- Class 1 lantibiotics undergo post-translational modifications by a LanBC complex.
- Nisin maturation involves dehydration by NisB and cyclization by NisC.
Purpose of the Study:
- To characterize the in vitro assembly of the nisin modification complex (NisBC).
- To determine the stoichiometry and structural features of the active NisBC complex.
- To investigate the role of substrate in NisBC complex formation.
Main Methods:
- In vitro characterization of NisBC complex assembly.
- Stoichiometry determination using analytical techniques.
- Small-angle X-ray scattering (SAXS) for structural analysis in solution.
Main Results:
- The NisBC complex forms only in the presence of the substrate, prenisin.
- The active complex consists of a NisB dimer, a NisC monomer, and one prenisin molecule.
- Formation of the final lanthionine ring inhibits complex assembly.
Conclusions:
- Substrate binding is essential for the assembly of the Class 1 lantibiotic modification complex.
- The characterized stoichiometry provides insights into the nisin maturation mechanism.
- SAXS analysis offers the first structural view of a LanBC complex in solution.
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