Glycogen Synthase (1-10) [PLSRTLSVSS-NH2], 5-FAM labeled

Product Name: Glycogen Synthase (1-10) [PLSRTLSVSS-NH2], 5-FAM labeled

Sequence One Letter Code: 5-FAM-PLSRTLSVSS-NH2

Sequence Three Letter Code: 5-FAM-Pro-Leu-Ser-Arg-Thr-Leu-Ser-Val-Ser-Ser-NH2

Chemical Formula:C65H90N14O21

Molecular Weight: 1403.5

Purity: 95%

Form: Lyophilized

Storage Conditions: - 20 °C Protected from light

Research Area: peptide substrate

Source / Species: guinea pig, rabbit

Conjugation: Conjugated

Conjugation Type: Fluorescent dyes

Code Nacres: NA.26

Application: Glycogen Synthase (1–10) [PLSRTLSVSS-NH₂], 5-FAM labeled, is a fluorescent peptide substrate widely used for Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) assays. The native decapeptide sequence serves as a well-characterized CaMKII substrate (Km ≈ 7.5 µM) and requires Ca²⁺ and calmodulin for phosphorylation. Conjugation with 5-FAM enables fluorescence-based detection at excitation/emission 494/521 nm, supporting real-time kinetic monitoring, enzymatic characterization, and inhibitor screening in studies of calcium-dependent signaling pathways.

Current Research: Glycogen Synthase (1–10) [PLSRTLSVSS-NH₂], 5-FAM labeled is a fluorescently tagged peptide substrate derived from the N-terminal phosphorylation sequence of glycogen synthase and extensively used for quantifying Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) activity. The native decapeptide sequence is a well-characterized CaMKII substrate with a reported Km ≈ 7.5 µM, enabling reliable kinetic characterization under defined assay conditions. Attachment of 5-carboxyfluorescein (5-FAM) allows sensitive fluorescence-based detection with excitation/emission maxima of approximately 494/521 nm, ensuring compatibility with standard FITC/GFP optical settings in plate readers and fluorescence instrumentation. Biological Context CaMKII is a serine/threonine kinase activated by binding of Ca²⁺-bound calmodulin. It plays essential roles in: Synaptic plasticity and long-term potentiation Cardiac contractility regulation Muscle physiology Cell cycle progression and transcriptional control Activation requires: Elevation of intracellular Ca²⁺ Formation of the Ca²⁺/calmodulin complex Association of this complex with CaMKII, triggering catalytic activity The glycogen synthase (1–10) peptide contains serine residues positioned within a CaMKII recognition motif, supporting efficient phosphorylation in the presence of Ca²⁺ and calmodulin. Assay Principle In CaMKII assays, the peptide substrate is incubated with: Active CaMKII ATP (phosphate donor) Mg²⁺ (cofactor) Ca²⁺ and calmodulin (activators) Phosphorylation of the serine residue can be monitored using fluorescence-compatible detection formats, including: Mobility shift–based fluorescence assays Coupled fluorescence kinase assays Mass spectrometry confirmation Phospho-specific detection workflows The 5-FAM tag enables direct fluorescent tracking of the peptide in real time. Research Applications 1. CaMKII Enzymatic Characterization The substrate supports determination of kinetic parameters (Km, Vmax, catalytic efficiency) in purified enzyme systems. 2. Calcium-Dependent Signaling Studies Because activity depends on Ca²⁺ and calmodulin, the peptide is useful for probing regulatory mechanisms controlling calcium-triggered phosphorylation events. 3. Inhibitor Screening The fluorescence format allows efficient evaluation of CaMKII inhibitors in medium- to high-throughput screening workflows, enabling IC₅₀ determination. 4. Comparative Kinase Profiling The substrate can be used to assess selectivity of CaMKII relative to other serine/threonine kinases under controlled conditions. Advantages Defined and well-characterized CaMKII substrate sequence Fluorescence compatibility (Ex/Em 494/521 nm) Suitable for real-time kinetic monitoring Compatible with microplate-based assay systems Applicable to enzymatic and cell lysate studies Experimental Considerations Optimal assay conditions require precise control of Ca²⁺ concentration and calmodulin availability. ATP and Mg²⁺ levels should be selected to avoid rate-limiting effects. Protection from light exposure is recommended to preserve fluorophore stability. Inclusion of CaMKII-selective inhibitors can validate assay specificity.