OPA-S-S-alkyne 

OPA-S-S-alkyne is a cell surface protein-selective labeling agent. OPA-S-S-alkyne selectively labels hyper-reactive extracellular lysines including ROR2 K382 and ENG K285, blocks ENG-BMP9 interaction, and labels purified human serum albumin with minimal bias. OPA-S-S-alkyne can be used for the research of hematologic and influenza A virus infection^[1][2][3].

OPA-S-S-alkyne (0.2-1 mM; 0.5-10 min) rapidly and efficiently labels the lysine residue on the synthetic model peptide Ac-GGYTLVSGYPK in a time- and concentration-dependent manner, with near-complete conversion achieved within 10 min at the highest tested concentration^[1].
OPA-S-S-alkyne (0.1-20 μM; 0.25-30 min) labels multiple lysine residues on purified myoglobin and labels purified BSA in a concentration- and time-dependent manner, with efficient labeling achieved at 10 μM within 0.25 min^[1].
The disulfide linker in OPA-S-S-alkyne is readily cleavable by the reducing agent DTT (HY-15917)^[1].
OPA-S-S-alkyne (100 μM; 1-10 min) selectively and efficiently labels cell surface lysines on living HeLa cells within 1 min, with no significant impact on cell viability after 10 min of treatment^[1].
OPA-S-S-alkyne (100 μM) selectively labels the hyper-reactive lysines K382 on ROR2 and K285 on ENG/CD105 in recombinant HEK293T-expressed proteins^[1].
OPA-S-S-alkyne (100 μM; 10 min) achieves near-complete, unbiased lysine labeling of purified HSA (HY-P1956)^[2].
OPA-S-S-alkyne (30 min at 4 °C) enables selective, non-damaging lysine labeling of living cell surfaces and sensitively captures EGF-induced conformational changes in EGFR, including increased accessibility of K328 and decreased accessibility of K489, as well as global cell surface protein conformational shifts linked to EGFR signaling^[2].
OPA-S-S-alkyne (30 min at 4 °C) enables sensitive profiling of IAV-induced conformational changes on living A549 cell surfaces, detecting widespread lysine accessibility shifts across 362 cell surface proteins, with conformation-responsive proteins enriched in viral entry-related functions and heavily sialylated^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

406.52

C₁₉H₂₂N₂O₄S₂

3059216-68-8

O=CC1=CC=C(C=C1C=O)CCNC(CCSSCCC(NCC#C)=O)=O

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Wang T, et al. A chemical proteomics approach for global mapping of functional lysines on cell surface of living cell. Nat Commun. 2024 Apr 8;15(1):2997.  [Content Brief]

  [2]. Ma S, et al. Living Cell Surfacome Lysine Footprinting (LiFT) Captures Virus-Induced Conformational Dynamics and Uncovers Influenza A Virus Host Factors. J Am Chem Soc. 2026;148(2):2260-2272.  [Content Brief]

  [3]. Zheng Z, et al. Covalent Modification of Protein by Chemical Probe in Living Cells for Structural and Interaction Studies. Chembiochem. 2025;26(1):e202400715.  [Content Brief]