Dataset Information

The C-terminal peptide of Aquifex aeolicus riboflavin synthase directs encapsulation of native and foreign guests by a cage-forming lumazine synthase.

ABSTRACT: Encapsulation of specific enzymes in self-assembling protein cages is a hallmark of bacterial compartments that function as counterparts to eukaryotic organelles. The cage-forming enzyme lumazine synthase (LS) from Bacillus subtilis (BsLS), for example, encapsulates riboflavin synthase (BsRS), enabling channeling of lumazine from the site of its generation to the site of its conversion to vitamin B2 Elucidating the molecular mechanisms underlying the assembly of these supramolecular complexes could help inform new approaches for metabolic engineering, nanotechnology, and drug delivery. To that end, we investigated a thermostable LS from Aquifex aeolicus (AaLS) and found that it also forms cage complexes with the cognate riboflavin synthase (AaRS) when both proteins are co-produced in the cytosol of Escherichia coli A 12-amino acid-long peptide at the C terminus of AaRS serves as a specific localization sequence responsible for targeting the guest to the protein compartment. Sequence comparisons suggested that analogous peptide segments likely direct RS complexation by LS cages in other bacterial species. Covalent fusion of this peptide tag to heterologous guest molecules led to their internalization into AaLS assemblies both in vivo and in vitro, providing a firm foundation for creating tailored biomimetic nanocompartments for medical and biotechnological applications.

SUBMITTER: Azuma Y

PROVIDER: S-EPMC5481547 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The C-terminal peptide of Aquifex aeolicus riboflavin synthase directs encapsulation of native and foreign guests by a cage-forming lumazine synthase.

Azuma Yusuke Y Zschoche Reinhard R Hilvert Donald D

The Journal of biological chemistry 20170517 25

Encapsulation of specific enzymes in self-assembling protein cages is a hallmark of bacterial compartments that function as counterparts to eukaryotic organelles. The cage-forming enzyme lumazine synthase (LS) from Bacillus subtilis (BsLS), for example, encapsulates riboflavin synthase (BsRS), enabling channeling of lumazine from the site of its generation to the site of its conversion to vitamin B2 Elucidating the molecular mechanisms underlying the assembly of these supramole ...[more]

PMID: 28515315

Similar Datasets

Project description:The integral membrane protein heme A synthase (HAS) catalyzes the biosynthesis of heme A, which is a prerequisite for cellular respiration in a wide range of aerobic organisms. Previous studies have revealed that HAS can form homo-oligomeric complexes, and this oligomerization appears to be evolutionarily conserved among prokaryotes and eukaryotes and is shown to be essential for the biological function of eukaryotic HAS. Despite its importance, little is known about the detailed structural properties of HAS oligomers. Here, we aimed to address this critical issue by analyzing the oligomeric state of HAS from Aquifex aeolicus (AaHAS) using a combination of techniques, including size exclusion chromatography coupled with multiangle light scattering (SEC-MALS), cross-linking, laser-induced liquid bead ion desorption mass spectrometry (LILBID-MS), and single-particle electron cryomicroscopy (cryo-EM). Our results show that HAS forms a thermostable trimeric complex. A cryo-EM density map provides information on the oligomerization interface of the AaHAS trimer. These results provide structural insights into HAS multimerization and expand our knowledge of this important enzyme.IMPORTANCE Heme A is a vital redox cofactor unique for the terminal cytochrome c oxidase in mitochondria and many microorganisms. It plays a key role in oxygen reduction by serving as an electron carrier and as the oxygen-binding site. Heme A is synthesized from heme O by an integral membrane protein, heme A synthase (HAS). Defects in HAS impair cellular respiration and have been linked to various human diseases, e.g., fatal infantile hypertrophic cardiomyopathy and Leigh syndrome. HAS exists as a stable oligomeric complex, and studies have shown that oligomerization of eukaryotic HAS is necessary for its proper function. However, the molecular architecture of the HAS oligomeric complex has remained uncharacterized. The present study shows that HAS forms trimers and reveals how the oligomeric arrangement contributes to the complex stability and flexibility, enabling HAS to perform its catalytic function effectively. This work provides the basic understanding for future studies on heme A biosynthesis.

Dataset Information

The C-terminal peptide of Aquifex aeolicus riboflavin synthase directs encapsulation of native and foreign guests by a cage-forming lumazine synthase.

Publications

The C-terminal peptide of <i>Aquifex aeolicus</i> riboflavin synthase directs encapsulation of native and foreign guests by a cage-forming lumazine synthase.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure