Thermo Scientific Pierce SATA is a short-chain (2.8 angstrom spacer arm) reagent for covalent modification of primary amines and addition of a protected yet exposable sulfhydryl group, enabling heterobifunctional crosslinking strategies.
SATA (N-succinimidyl S-acetylthioacetate) adds sulfhydryl groups to proteins and other amine-containing molecules in a protected form. The modified molecule can be stored indefinitely and treated with hydroxylamine to expose the labile sulfhydryl group when needed for conjugation reactions. SATA contains an N-hydroxysuccinimide (NHS) ester, which forms a stable, covalent amide bond with primary amines (i.e., lysine residues and the amino termini of proteins) and releases NHS as a by-product. De-protection (deacylation) to generate a free sulfhydryl is accomplished using hydroxylamine-HCl. SATA is available as the reagent alone and in the Sulfhydryl Addition Kit, which contains all necessary components to introduce free sulfhydryl groups into any primary amine-containing molecule, purify the modified molecule and quantify the added sulfhydryl groups.
- Adds a protected sulfhydryl that can be deprotected by hydroxylamine
- Allows long-term storage of the sulfhydryl-modified molecule
- Forms cleavable disulfide bonds with other sulfhydryl-containing molecules
- Reacts with primary amines (e.g., lysine residues proteins) to form stable amide bonds
- Preserves protein activity with its mild, non-denaturing reaction conditions
Structure and properties of SATA:
- Functional groups: NHS ester (amine-reactive) and sulfhydryl (protected)
- Spacer arm length: 2.8 angstroms
- Molecular weight: 231.23
- Chemical formula: C8H9NO5S
- CAS number: 76931-93-6
Sulfhydryl groups present on proteins, peptides and other compounds are important in protein chemistry/modification reactions. Frequently, thiols are unavailable or absent within the molecules of interest. Several reagents and techniques are available for introducing sulfhydryl groups or disulfides into proteins and peptides, including Traut's Reagent, variants of SPDP, and variants of SATA.
|Reaction and modification scheme for NHS-activated S-acetyl reagents.
- Duncan, R.J.S., et al. (1983). A new reagent which may be used to introduce sulfhydryl groups into proteins, and its use in the preparation of conjugates for immunoassay. Anal Biochem 132: 68-73.
Overview of crosslinking and protein modification
SATP – slightly longer version of SATA
SAT(PEG)4 – alternative sulfhydryl-addition reagent with long, PEG spacer arm
Hydroxylamine – deprotects sulfhydryls after SATA modification
Traut's Reagent– small thiolation compound
SPDP – amine-to-sulfhydryl crosslinker