AEBSF

AEBSF or 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride is a water-soluble, irreversible serine protease inhibitor with a molecular weight of 239.5 Da. It inhibits proteases like chymotrypsin, kallikrein, plasmin, thrombin, and trypsin. The specificity is similar to the inhibitor PMSF, nevertheless AEBSF is more stable at low pH values. Typical usage is 0.1 - 1.0 mM. AEBSF (marketed as Pefabloc SC from the company Pentapharm) was first reported for use in biochemistry in 1993, and came into common use for the inhibition serine proteases and of non-protease enzymes such as acetylhydrolases in the mid 1990s.^[2]

AEBSF

Names
Preferred IUPAC name 4-(2-Aminoethyl)benzene-1-sulfonyl fluoride
Other names Pefabloc SC
Identifiers
CAS Number	34284-75-8 N 30827-99-7 (hydrochloride salt)
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL1096339 Y
ChemSpider	1638 Y
DrugBank	DB07347 Y
MeSH	AEBSF
PubChem CID	1701
UNII	F5D36L5354 Y
CompTox Dashboard (EPA)	DTXSID40187844
InChI InChI=1S/C8H10FNO2S/c9-13(11,12)8-3-1-7(2-4-8)5-6-10/h1-4H,5-6,10H2 Y Key: MGSKVZWGBWPBTF-UHFFFAOYSA-N Y InChI=1/C8H10FNO2S/c9-13(11,12)8-3-1-7(2-4-8)5-6-10/h1-4H,5-6,10H2 Key: MGSKVZWGBWPBTF-UHFFFAOYAK
SMILES FS(=O)(=O)c1ccc(cc1)CCN
Properties
Chemical formula	C8H10FNO2S.HCl
Molar mass	239.69 g/mol
Solubility in water	200 mg/mL[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Mechanism of action

AEBSF is targeted to covalently modify the hydroxyl of serine residues, where it causes an additional 183.0354 Da to be added to each modified residue, but other off-target residues such as tyrosine, lysine, histidine, and the protein N-terminal amino group, have also been reported.^[3][4] Due to the substantial frequency of modification of these off-target residues in unoptimized protocols, some users recommend not using AEBSF for highly sensitive proteomics applications, and instead recommend using fresh (and comparatively unstable) PMSF.^[3] Both AEBSF and PMSF are sulfonyl fluorides and are sulfonylating agents.^[5] Sulfonyl fluorides act by reacting with the hydroxy group of the active site serine residue to form a sulfonyl enzyme derivative. This derivative may be stable for long periods of time except at high pH.^[6]

Use in cholesterol regulation studies

AEBSF is extensively used in studies aiming to describe cholesterol regulatory genes due to its potent ability to inhibit Site-1-protease (S1P). This serine protease, located in the Golgi apparatus, is responsible for activating the sterol regulatory element-binding proteins (SREBP). By selectively inhibiting S1P, AEBSF can be used to characterize the downstream result of SREBP inhibition and its influence on cholesterol regulation.

See also

• PMSF
• DFP (diisopropyl fluorophosphate), an analogous fluorophosphonate phosphorylating reagent