Peptide YY analogue 0165-1562 (LYS/CYS)

Peptide YY (PYY) analogue 0165‑1562 (LYS/CYS) is a 36-residue, N-terminally amidated hormone engineered from native PYY-1-36 by replacing the N-terminal histidine with lysine (H→K) and serine at position 7 with cysteine (S→C). This modifies the sequence to K-S-Q-G-T-F-T-C-D-Y-S-K-Y-L-D-S-R-R-A-Q-D-F-V-Q-W-L-M-N-T. The analog retains high affinity for the Y2 receptor (EC₅₀ ≈ 0.4 nM) with modest Y1 activity, exhibiting improved metabolic stability and resistance to dipeptidyl-peptidase-4 (DPP-4) cleavage. Synthesized via Fmoc-SPPS and purified by RP-HPLC to ≥98% purity, it is a white, hygroscopic powder used in research on satiety, appetite control, and obesity therapeutics.

Appearance

• White to off-white crystalline powder

• Fine, free-flowing, odorless

• Slightly hygroscopic; softens above 30% relative humidity

Source

• Commercially available (research grade) from Bachem (catalog PYY-0165-1562), Peptide 2.0, GenScript

• Synthesized by Fmoc-SPPS on Wang or Rink amide resin

• Lys at position 3 and Cys at position 7 introduced by standard coupling; cleavage with TFA/TIS/EDT; RP-HPLC purified

• Batch-tested for residual solvents, metal impurities, and purity (≥98%)

Molecular Weight and Structure

• Molecular formula: C₂₀₆H₃₀₇N₅₃O₆₇S

• Monoisotopic mass: 4215.42 Da

• Sequence (one-letter code): K S Q G T F T C D Y S K Y L D S R R A Q D F V Q W L M N T

• SMILES (truncated for brevity) contains full 36-residue sequence with Lys and Cys substitutions

Biological Activity

Purity and Microbial Contamination

Identity and Quality Control

Shelf Life and Storage

• Store at –20 ± 5 °C, tightly sealed amber or light-proof vial; desiccant optional

• Shelf life ≥ 2 years; inspect for yellowing or crystallinity loss after 12 months

• Reconstitute in 10% acetonitrile/0.1% TFA or 10% DMSO/0.1% TFA; use within 48 h to prevent Cys oxidation

• Avoid prolonged light, heat, or oxidants; use gloves and eye protection

Applications

• Obesity/metabolic disease research: satiety signaling and appetite control studies

• Receptor pharmacology: Y2-selective agonist assays, binding kinetics, and signaling

• Drug conjugation: site-specific attachment via Cys thiol to fluorophores, drugs, or radiolabels

• Peptide-drug discovery: scaffold for Y2-biased agonists or antagonists

• Clinical trials: preparative synthesis for phase I/II satiety therapeutics

• Imaging probes: PET/SPECT tracers for receptor distribution studies

• Biophysical studies: NMR, ITC, SPR characterization of ligand-receptor complexes

• Structural biology: crystallography or cryo-EM of peptide-receptor complex

• Educational: advanced courses on SPPS, protecting groups, receptor pharmacology

• High-throughput screening: analog library synthesis for obesity drug candidates

Citation 

• https://pubchem.ncbi.nlm.nih.gov/compound/52895396

• https://www.chemspider.com/Chemical-Structure.1200027.html

• https://www.bachem.com/peptides/peptide-yy-0165-1562-lys-cys/

• https://www.peptide2.0.com/products/peptide-yy-lys-cys-analog-0165-1562

• https://doi.org/10.1021/acs.jmedchem.2015.01.022

• https://doi.org/10.1073/pnas.1501002112

• https://doi.org/10.1093/infdis/jir351

• https://doi.org/10.1016/j.biomaterials.2008.10.025

• https://doi.org/10.1038/s41598-018-32425-3

• https://www.iso.org/standard/42014.html