SMCC

Thermo Scientific Pierce SMCC is an amine-to-sulfhydryl crosslinker that contains NHS-ester and maleimide reactive groups at opposite ends of a medium-length cyclohexane-stabilized spacer arm (8.3 angstroms).

Succinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SMCC) is a non-cleavable and membrane permeable crosslinker. It contains an amine-reactive N -hydroxysuccinimide (NHS ester) and a sulfhydryl-reactive maleimide group. NHS esters react with primary amines at pH 7-9 to form stable amide bonds. Maleimides react with sulfhydryl groups at pH 6.5-7.5 to form stable thioether bonds. The maleimide groups of SMCC and Sulfo-SMCC and are unusually stable up to pH 7.5 because of the cyclohexane bridge in the spacer arm.

SMCC Highlights

• Amine reactive NHS ester crosslinks rapidly with primary amine-containing molecule
• Sulfhydryl-reactive maleimide reacts with cysteine residues to yield specific conjugates
• High purity, crystalline SMCC can be used to create high-purity maleimide-activated derivatives
• Cyclohexane bridge confers added stability to the maleimide group making SMCC an ideal crosslinking agent for maleimide activation of proteins. Maleimide groups are stable for 64 hours in 0.1 M sodium phosphate buffer, pH 7 at 4°C.

Applications for SMCC

• Ideal reagent for enzyme labeling of antibodies, both enzyme activity and antibody specificity can be preserved
• Create specific bioconjugates via one- or two-step crosslinking reactions
• Create sulfhydryl-reactive, maleimide-activated carrier proteins for coupling haptens

Product Details:

SMCC is often used for the preparation of antibody-enzyme and hapten-carrier conjugates. In this type of conjugation, the NHS ester is reacted first with the antibody, excess crosslinking reagent removed and then the sulfhydryl-containing enzyme molecule is added. This two-step reaction scheme results in formation of specific antibody-enzyme conjugates.

SMCC is a reagent of choice for creating stable maleimide-activated carrier proteins that will spontaneously react with sulfhydryls. In this application, the NHS ester of SMCC is reacted with lysine residues on the carrier protein, converting them to reactive maleimides. These relatively stable maleimide-activated intermediates may be lyophilized and stored for later conjugation to a hapten.

References:

1. Uto, I., et al. (1991). J. Immunol. Methods 138, 87-94.
2. Bieniarz, C., et al. (1996). Extended Length Heterobifunctional Coupling Agents for Protein Conjugations. Bioconjug. Chem. 7, 88-95.
3. Chrisey, L.A., et al. (1996). Nucleic Acids Res. 24(15), 3031-3039.
4. Kuijpers, W.H., et al. (1993). Bioconjug. Chem. 4(1), 94-102.
5. Brinkley, M.A. (1992). A survey of methods for preparing protein conjugates with dyes, haptens and crosslinking reagents. Bioconjugate Chem. 3, 2-13.
6. Hashida, S., et al. (1984). More useful maleimide compounds for the conjugation of Fab to horseradish peroxidase through thiol groups in the hinge. J. Appl. Biochem. 6, 56-63.
7. Mattson, G., et al. (1993). A practical approach to crosslinking. Molecular Biology Reports 17, 167-183.
8. Partis, M.D., et al. (1983). Crosslinking of proteins by omega-maleimido alkanoyl N-hydroxysuccinimide esters. J. Protein. Chem. 2, 263-277.
9. Samoszuk, M.K., et al. (1989). A peroxide-generating immunoconjugate directed to eosinophil peroxidase is cytotoxic to Hodgkin’s disease cells in vitro. Antibody, Immunoconjugates and Radiopharmaceuticals 2, 37-45.
10. Yoshitake, S., et al. (1982). Mild and efficient conjugation of rabbit Fab and horseradish peroxidase using a maleimide compound and its use for enzyme immunoassay. J. Biochem. 92, 1413-1424.

Related Products:

Sulfo-SMCC
Bioconjugate Techniques (book)
Maleimide Activated Carrier Proteins and Kits