Sigma-Aldrich Anti-Pan-Fmet 25 ╡L

KLH-conjugated, N-terminal formylmethionine synthetic peptide (fMet-Xaa-Cys).

Quality Control Testing

Evaluated by Western Blotting in lysate from DH5 cells treated with Actinonin.

Western Blotting Analysis: A 1:1,000 dilution from a representative lot detected N-terminal formylmethionine bearing proteins in lysate from DH5 cells treated with Actinonin but, not in DH5 cells treated with Ethanol.

Tested Applications

Western Blotting Analysis: A representative lot detected fMet (N-terminal formylmethionine) in Western Blotting application.

ELISA: A representative lot of this antibody detected GST-tagged recombinant fMD-D2(3-11) in ELISA application.

Note: Actual optimal working dilutions must be determined by end user as specimens, and experimental conditions may vary with the end user.

This polyclonal antibody specifically detects fMet (N-terminal formylmethionine) bearing proteins and their derivatives.

Rabbit polyclonal antibody in serum without azide.

Please refer to guidance on suggested starting dilutions and/or titers per application and sample type.

Store at -10°C to -25°C. Handling Recommendations: Upon receipt and prior to removing the cap, centrifuge the vial and gently mix the solution. Aliquot into microcentrifuge tubes and store at -20°C. Avoid repeated freeze/thaw cycles, which may damage IgG and affect product performance.

Concentration: Please refer to the Certificate of Analysis for the lot-specific concentration.

N-terminal formyl-methionine (fMet) is a unique amino acid that serves as the initiating residue in protein synthesis in bacteria and mitochondria, playing a pivotal role in various cellular processes. Structurally, fMet is characterized by the addition of a formyl group to the methionine, which influences the stability and function of nascent polypeptides. Nt-fMet is produced pre-translationally by formyltransferases, which use 10-formyltetrahydrofolate as a cosubstrate. By contrast, proteins synthesized by cytosolic ribosomes of eukaryotes are presumed to bear unformylated N-terminal Met (Nt-Met). The unformylated Nt-Met residue of eukaryotic proteins is often co-translationally Nt acetylated, a modification that creates specific degradation signals, Ac/Ndegrons, which are targeted by the Ac/N-end rule pathway. Functionally, fMet acts as a degradation signal in the N-end rule pathway, guiding the proteolytic fate of proteins. In eukaryotic cells, fMet-containing proteins can be synthesized in mitochondria and the cytosol, with recent studies indicating substantial upregulation of fMet-containing proteins in various cancer cell lines, suggesting a potential link to tumor progression and metastasis. Subcellular localization of fMet-containing proteins is crucial, as their presence in mitochondrial membranes is essential for the assembly of respiratory complexes. Dysregulation of fMet metabolism has been implicated in several diseases, including cancer and mitochondrial disorders. Both bacterial and eukaryotic ribosomes can initiate protein synthesis with formylmethionine (fMet), but detecting fMet-bearing peptides and fMet-bearing proteins has been challenging due to the lack of effective anti-fMet antibodies. This anti-pan-fMet polyclonal Ab specifically detects N-terminal formylmethionine-bearing proteins and their derivatives. It is suitable for western blotting, dot-blotting and ELISA validations. (Ref.: Kim, D., et al. (2025). BioTechniques. 77(2); 46-55; Kim, D., et al. (2023). J. Bio. Chem. 299(5);104652; Kim, JM., et al. (2018). Science. 362(6418); eaat0174).

Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.