SOBER1

SOBER1 is an enzyme that catalyzes the biochemical reaction of deacetylation.^[1] The SOBER (Suppressor of AvrBsT-elicited resistance) 1 protein is conserved in plants and it suppresses the plant's ability to carry out the hypersensitive response against infection by certain pathogenic effector proteins from the YopJ family.^[2] SOBER1 belongs to the protein superfamily of α/β hydrolases and possesses a canonical serine/histidine/aspartate catalytic triad to carry out the deacetylation reaction. There have been contradicting reports about SOBER1's potential phospholipase activity, with one study claiming phospholipase A₂ activity of the protein^[3] and another study being unable to reproduce this result.^[1]

Crystal structure of Arabidopsis thaliana SOBER1, PDB code 6avv. Alpha helices are in red, beta strands in gold, catalytic site residues in black.
Identifiers
Symbol	SOBER1
InterPro	IPR029058
CATH	6avv
SCOP2	6avv / SCOPe / SUPFAM

Relationship to acyl-protein thioesterases

Members of the SOBER1 family are considered closely related to acyl-protein thioesterases, judged by their protein structure.^[2] However, a change in their amino acid sequence renders SOBER1's biochemical properties into a deacetylase; in particular the hydrophobic tunnel, which is found in acyl-protein thioesterases, is impaired by additional amino acids in the lid structure of SOBER1, creating a new surface for binding of the acetyl group.^[1]

Mechanism of SOBER1 deacetylase function, highlighting the additional amino acids in the protein lid. Nature Communications 8(1):2201, Creative Commons Attribution 4.0 International License, https://creativecommons.org/licenses/by/4.0/

Targets

So far, the following proteins have been identified as SOBER1 targets: AvrBsT; ACIP1.

See also

• Acylation
• Catalytic triad
• Compendium of protein lysine acetylation
• Enzyme assay
• Organic synthesis
• Protein dynamics
• Proteolysis
• The Proteolysis Map