What is SUMO and SUMOylation?
Small Ubiquitin-like Modifier (or SUMO) proteins are a family of small proteins that are covalently attached to and detached from other proteins in cells to modify their function. This process is called SUMOylation (sometimes written sumoylation).
What is SUMO tag used for?
SUMO Tag Definition Sumo tag is most frequently used as N-end fusion sequence in yeast to increase the expression and solubility of the desired recombinant protein. SUMO proteins are similar to ubiquitin in their folded structure but possess only about 20% homology to the amino acid sequence of ubiquitin.
Which amino acids can be Sumoylated?
Lysine is one of 20 common amino acids. Because of its physical and chemical properties, it can interact with several proteins or substrates. With respect to PTM, lysine is not only the most frequently modified amino acid but also the one subjected to the widest range of PTMs, which include SUMOylation.
What is protein ubiquitination?
Ubiquitylation (also known as ubiquitination or ubiquitinylation) is an enzymatic post-translational modification in which a ubiquitin protein is attached to a substrate protein. This process most commonly binds the last amino acid of ubiquitin (glycine 76) to a lysine residue on the substrate.
Is ubiquitin a protein?
Ubiquitin is a small, 76-amino-acid protein. Ubiquitylation is a post-translational modification that forms an isopeptide bond between a lysine residue on the protein and the carboxyl terminus of ubiquitin. The ubiquitylation system consists of four different classes of enzymes: E1–E4.
Can ubiquitin be targeted for ubiquitination?
Ubiquitin (Ub), a highly conserved regulatory protein containing 76 amino acids, can be covalently tagged to target proteins via a cascade of enzymatic reactions, including Ub-activating (E1), Ub-conjugating (E2) and Ub-ligating (E3) enzymes.
What residues can be ubiquitinated?
Ubiquitin can be ubiquitinated on seven lysine (Lys) residues or on the N-terminus, leading to polyubiquitin chains that can encompass complex topologies. Alternatively or in addition, ubiquitin Lys residues can be modified by ubiquitin-like molecules (such as SUMO or NEDD8).
Which amino acids can form isopeptide bonds?
An isopeptide bond is the type of peptide bond that forms between the between the carboxyl group and an amino group of joining amino acids where at least one of them is part of the side chain. It may also form between the gamma-carboxamide group of glutamine and the primary amine of certain amino acids.