Hydroxypyruvic acid lithium hydrate is an intermediate in the metabolism of serine, glycine, and threonine. It is a substrate for serine-pyruvate aminotransferase and glyoxylate reductase hydroxypyruvate reductase.
The renin fluorogenic substrate consists of the normal peptide substrate for renin which has been linked to the fluorophore EDANS at one end and to a non-fluorescent quenching molecule (Dabcyl) at the other. After cleavage by renin, the product (peptide-EDANS) is brightly fluorescent and can be easily analyzed using an excitation wavelength of 340 nm and emission wavelengths of 485-510 nm.
Enteropeptidase fluorogenic substrate is a substrate for enteropeptidase that contains a 7-amino-4-trifluoromethylcoumarin (AFC) moiety. Enteropeptidase is a serine protease expressed in the proximal small intestine of higher animals that converts inactive trypsinogen to active trypsin by endoproteolytic cleavage.1,2Enteropeptidase recognizes the highly specific amino acid sequence DDDDK on the fluorogenic substrate and cleaves after the lysine residue, releasing the AFC moiety. Enteropeptidase activity is quantified by fluorescent detection of AFC, which displays excitation/emission spectra of 380/500 nm.3
Cyclin-dependent kinase 5 (Cdk5) is a serine threonine kinase that is predominantly active in neuronal tissues. With p25 or p35, Cdk5 phosphorylates a range of proteins, including histone H1 and tau. Cdk5 substrate is a synthetic peptide (PKTPKKAKKL) corresponding to a sequence of histone H1. It is phosphorylated by Cdk5 with a Km value of 5 μM.
Renin FRET Substrate I is a specific compound that functions as a substrate for human renin. It is specifically designed to contain the exact cleavage site found in the N-terminal peptide of human angiotensinogen.