Difference between revisions of "Part:BBa K4863002"

Revision as of 13:01, 9 October 2023

S-layer protein (Slp)

S-layer protein (Slp) is a native protein on the cell surface of cyanobacteria. It is encoded by the gene sll1951 in Synechocystis PCC6803. This protein forms a lattice that is about 30nm wide that covers the cell surface, forming the paracrystalline S-layer. It has an undefined signal peptide at C-terminus.

Fusion of a protein to the N-terminus of Slp is shown to be an effective system for functional surface display since it would yield a cell entirely covered with the fusion protein on the outermost layer.

Usage and Biology

Following the potential of cyanobacteria as a cell factory for biofuel or biomaterials, functional surface display of proteins in cyanobacteria is beneficial in many ways: it can allow for better enzyme performance via improved binding with substrate, achieve immobilization of cells, and more. Cyanobacteria have a thick peptidoglycan layer and an additional S-layer, making effective surface display difficult. S-layer protein (Slp) is the product of sll1951 in Synechocystis. It makes up the extracellular paracrystalline S-layer outside of the cyanobacterial cell wall and is the only component of this outermost layer. Slp has an undefined signal peptide at C-terminus, and fusion of another protein at the N-terminus of Slp would yield a Synechocystis cell completely covered with the fusion protein on the outermost layer and is thus an effective method for surface display (Cengic et al., 2018).

The S-layer of cyanobacteria, which entirely constitutes of the Slp protein, is believed to be involved in carbon sequestration and other physiochemical processes. Slp self-assembles into lattice form via an entropy-driven process in extracellular space. In Synechocystis PCC 6803, the Sll1951 gene, a 5226bp open reading frame, encodes for the hemolysin-like S-layer protein.

Characterization

Sequence and Features