Material Data Sheet

Ubiquitin Mutant I44A

Price: $89.00
Catalog #: UM-I44A

Ubiquitin Mutant I44A

1 mg

Ile44 is a surface hydrophobic residue that is important for poly-ubiquitin chain interaction and recognition by the 26S proteasome and other enzymes involved in ubiquitination. Together with Leu8 and Val70, this isoleucine forms the important hydrophobic patch critical for proteasomal degradation. Ile44 also forms a di-leucine signal with Leu43 that may be involved in mediating endocytosis of substrate proteins that are mono-ubiquitinated. However, this di-leucine signal is not the sole determinant for endocytic internalization. Ubiquitin I44A can form an E1-catalyzed active thioester at the C-terminus allowing the molecule to be transferred to the lysines of substrate proteins.

Product Information

Soluble and stable in aqueous buffers up to 10 mg/ml.
8.5 kDa
> 95% by SDS-PAGE
This is a lyophilized powder

Use & Storage


Typical concentrations for non rate-limiting support of in vitro conjugationreactions range from 200 μM-1 mM depending on experimental conditions.


Store at -20°C after solubilization in desired buffer. Avoid multiple freeze/thaw cycles.



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