A widespread bacterial protein compartment sequesters and stores elemental sulfur

• DOI: 10.1126/sciadv.adk9345
• Publication Date: 2024-02-02T18:58:50Z
• Authors: Robert Benisch; Michael P. Andreas; Tobias W. Giessen
• Keywords: Compartmentalization (fire protection); Compartment (ship); Organelle; Cellular compartment

Subcellular compartments often serve to store nutrients or sequester labile toxic compounds. As bacteria mostly do not possess membrane-bound organelles, they have rely on protein-based compartments. Encapsulins are one of the most prevalent compartmentalization strategies found in prokaryotes. Here, we show that desulfurase encapsulins can and large amounts crystalline elemental sulfur. We determine 1.78-angstrom cryo-EM structure a 24-nanometer desulfurase-loaded encapsulin. Elemental sulfur crystals be formed inside encapsulin shell desulfurase-dependent manner with l -cysteine as donor. Sulfur accumulation influenced by concentration type source growth medium. The selectively permeable protein allows storage redox-labile excluding cellular reducing agents, while encapsulation substantially improves activity stability. These findings represent an example compartment able accumulate