Enterokinase Substrate

Product Name: Enterokinase Substrate

Sequence One Letter Code: GDDDDK-ßNA

Sequence Three Letter Code: H-Gly-Asp-Asp-Asp-Asp-Lys-ßNA

Cas No: 70023-02-8

Chemical Formula:C34H44N8O14

Molecular Weight: 788.8

Purity: 95%

Form: Lyophilized

Storage Conditions: - 20 °C

Research Area: peptide substrate

SMILES: C1=CC=C2C=C(C=CC2=C1)NC(=O)[C@H](CCCCN)NC(=O)C(CC(=O)O)NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](CC(=O)O)NC(=O)CN

IUPAC: (3S)-3-[(2-aminoacetyl)amino]-4-[[(2S)-1-[[(2S)-1-[[1-[[(2S)-6-amino-1-(naphthalen-2-ylamino)-1-oxohexan-2-yl]amino]-3-carboxy-1-oxopropan-2-yl]amino]-3-carboxy-1-oxopropan-2-yl]amino]-3-carboxy-1-oxopropan-2-yl]amino]-4-oxobutanoic acid

INCHIKEY: QLLWULMEPVZWTP-VPRBCIFISA-N

INCHI:

InChI=1S/C34H44N8O14/c35-10-4-3-7-20(30(52)37-19-9-8-17-5-1-2-6-18(17)11-19)39-32(54)22(13-27(46)47)41-34(56)24(15-29(50)51)42-33(55)23(14-28(48)49)40-31(53)21(12-26(44)45)38-25(43)16-36/h1-2,5-6,8-9,11,20-24H,3-4,7,10,12-16,35-36H2,(H,37,52)(H,38,43)(H,39,54)(H,40,53)(H,41,56)(H,42,55)(H,44,45)(H,46,47)(H,48,49)(H,50,51)/t20-,21-,22?,23-,24-/m0/s1

Source / Species:

Conjugation: Unconjugated

Code Nacres: NA.26

Application: This synthetic peptide serves as a specific substrate for enterokinase (enteropeptidase), a membrane-bound serine protease responsible for activating trypsinogen to trypsin in the duodenum. Enterokinase-mediated cleavage initiates the proteolytic cascade that activates pancreatic digestive enzymes. The peptide is suitable for enzymatic activity assays, substrate specificity studies, and characterization of enterokinase and proenteropeptidase function. It may also be used to monitor downstream trypsin-mediated activation processes. This reagent supports research in digestive enzyme regulation, gastrointestinal physiology, and protease mechanism studies.

Current Research: Proteolytic enzymes play a crucial role in digestive physiology, enabling the breakdown of dietary proteins into absorbable peptides and amino acids. A key regulatory step in this process is the activation of trypsinogen, the inactive precursor of trypsin, which subsequently triggers a cascade of digestive enzyme activation in the small intestine. This activation is initiated by enterokinase (enteropeptidase), a membrane-bound serine protease expressed on the brush border of duodenal epithelial cells. Synthetic peptide substrates designed for enterokinase provide valuable experimental tools for investigating this enzymatic process and the regulatory mechanisms governing digestive protease activation. Enterokinase and the Initiation of Digestive Enzyme Cascades Enterokinase is a specialized protease responsible for converting trypsinogen into active trypsin. This conversion occurs when enterokinase cleaves a specific peptide sequence located at the N-terminus of trypsinogen. The cleavage releases a short activation peptide and exposes the catalytic site of trypsin, enabling the enzyme to become active. Once activated, trypsin acts as a central regulator of the pancreatic digestive enzyme cascade. It cleaves and activates several other protease precursors secreted by the pancreas, including chymotrypsinogen, proelastase, and procarboxypeptidases. Through this cascade, a single activation event initiated by enterokinase leads to the coordinated activation of multiple enzymes involved in protein digestion. Because of its critical role in initiating this pathway, enterokinase functions as a key control point in gastrointestinal proteolysis. Structure and Function of Enterokinase Enterokinase is a type II transmembrane serine protease composed of a heavy chain and a catalytic light chain. The enzyme is anchored to the intestinal epithelial membrane through its heavy chain, while the light chain contains the protease domain responsible for substrate cleavage. The enzyme recognizes a specific amino acid sequence that precedes the cleavage site in trypsinogen. This sequence typically contains a cluster of acidic residues followed by a lysine residue where cleavage occurs. The specificity of this recognition sequence allows enterokinase to selectively activate trypsinogen while avoiding nonspecific proteolysis of other proteins. Synthetic peptides that incorporate this recognition motif can therefore serve as model substrates for enterokinase activity assays. Synthetic Peptide Substrates for Enzyme Studies Synthetic peptide substrates provide a simplified system for studying protease activity. By reproducing the cleavage sequence recognized by enterokinase, these peptides allow researchers to examine enzyme behavior under controlled laboratory conditions. In enzymatic assays, the peptide substrate is incubated with enterokinase, and cleavage of the peptide can be measured using biochemical or spectroscopic detection methods. This approach enables quantitative analysis of enzyme activity and substrate recognition. Because the peptide sequence is precisely defined, it can also be modified to explore how changes in amino acid composition affect substrate specificity and cleavage efficiency. Applications in Enzymatic Activity Assays One of the primary uses of enterokinase substrate peptides is in enzymatic activity assays. These experiments measure how efficiently enterokinase cleaves its target sequence under various conditions. By monitoring substrate cleavage rates, researchers can determine kinetic parameters such as catalytic efficiency, substrate affinity, and reaction velocity. Such assays help clarify the biochemical properties of enterokinase and its role in digestive physiology. These assays are also useful for evaluating the activity of recombinant enterokinase enzymes produced for research or biotechnological applications. Studying Proenteropeptidase Activation Enterokinase itself is synthesized as an inactive precursor known as proenteropeptidase, which requires proteolytic processing to become fully active. Synthetic peptide substrates can be used to examine how this activation occurs and how the mature enzyme recognizes its substrates. Investigating the transition from proenzyme to active enzyme helps researchers understand the regulatory mechanisms that control protease activation in the digestive tract. Monitoring Trypsin Activation Cascades Because enterokinase initiates the trypsin activation pathway, peptide substrates can also be used to study downstream proteolytic cascades. After enterokinase activates trypsinogen, the resulting trypsin molecules can activate additional digestive enzymes. Experimental systems using defined peptide substrates allow researchers to monitor how the initial activation event leads to a cascade of protease activity. These studies contribute to understanding how digestive enzyme networks are coordinated and regulated. Relevance to Gastrointestinal Physiology Proper regulation of digestive proteases is essential for maintaining gastrointestinal health. Premature activation of trypsinogen within the pancreas can lead to tissue damage and inflammation, while insufficient enzyme activation in the intestine can impair protein digestion. Studying enterokinase activity helps researchers understand how digestive enzyme activation is controlled spatially and temporally within the gastrointestinal tract. Insights gained from these studies contribute to broader understanding of digestive physiology and enzyme regulation. Applications in Protease Mechanism Studies Beyond digestive physiology, enterokinase substrates are valuable tools for investigating serine protease catalytic mechanisms. Because the enzyme exhibits high sequence specificity, it serves as a useful model for studying how proteases recognize and cleave peptide substrates. Experiments using synthetic peptides allow researchers to examine how substrate structure influences enzyme binding and catalytic activity. These studies contribute to understanding the molecular principles underlying protease function. Conclusion Synthetic peptide substrates designed for enterokinase (enteropeptidase) provide powerful tools for studying the enzymatic processes that initiate protein digestion in the small intestine. By mimicking the cleavage sequence found in trypsinogen, these peptides enable precise analysis of enzyme activity, substrate specificity, and proteolytic cascades. Through applications in enzyme kinetics, protease activation studies, and investigations of digestive physiology, enterokinase substrate peptides support research aimed at understanding the regulation and mechanisms of gastrointestinal proteolysis.