H-D-Phe-Pip-Arg-pNA.2HCl

H-D-Phe-Pip-Arg-pNA.2HCl, also known as N-Benzoyl-D-phenylalanyl-L-pipecolyl-L-arginine p-nitroanilide dihydrochloride, is a synthetic peptide substrate widely recognized for its utility in enzymatic assays, particularly those involving serine proteases such as trypsin-like enzymes. Characterized by a chromogenic p-nitroanilide (pNA) group, this compound enables precise detection and quantification of enzymatic activity through colorimetric methods. Its structure, incorporating D-phenylalanine, pipecolic acid, and arginine residues, confers selectivity and specificity, making it a preferred choice for researchers seeking to investigate substrate-enzyme interactions or to screen for protease inhibitors in various biochemical contexts. The dihydrochloride salt form enhances its solubility and stability in aqueous solutions, ensuring consistent performance in laboratory settings.

Enzyme Kinetics Studies: H-D-Phe-Pip-Arg-pNA.2HCl is extensively used in enzyme kinetics research to characterize the catalytic parameters of serine proteases. By serving as a chromogenic substrate, it allows for real-time monitoring of enzymatic cleavage via the release of p-nitroaniline, which can be quantitatively measured spectrophotometrically. This enables the determination of kinetic constants such as Km and Vmax, facilitating in-depth analysis of enzyme specificity, catalytic efficiency, and the effects of potential modulators or inhibitors. Its defined peptide sequence ensures that the observed activity is attributable to specific proteolytic mechanisms, thereby supporting high-precision kinetic modeling.

Protease Inhibitor Screening: In drug discovery and biochemical research, H-D-Phe-Pip-Arg-pNA.2HCl plays a crucial role in the screening and evaluation of protease inhibitors. By incorporating this substrate into high-throughput assay formats, scientists can rapidly assess the inhibitory potential of small molecules, peptides, or natural products against target proteases. The colorimetric readout provided by pNA release offers a sensitive and scalable approach to rank inhibitor potency, investigate structure-activity relationships, and optimize lead compounds for further development. This application is particularly valuable in the context of identifying novel therapeutic agents or elucidating the regulatory mechanisms of proteolytic pathways.

Substrate Specificity Profiling: The unique sequence of H-D-Phe-Pip-Arg-pNA.2HCl enables researchers to probe the substrate specificity of various proteases, including those with trypsin-like or chymotrypsin-like activity. By comparing the cleavage efficiency of this substrate with others containing different amino acid sequences, scientists can map the substrate recognition preferences of enzymes, identify critical binding determinants, and design more selective substrates or inhibitors. This information is fundamental to understanding protease function in physiological and pathological processes, as well as to engineering enzymes with tailored specificity for biotechnological applications.

Biochemical Pathway Elucidation: Researchers frequently utilize H-D-Phe-Pip-Arg-pNA.2HCl to dissect complex proteolytic cascades in cellular or tissue extracts. By monitoring the generation of p-nitroaniline in response to endogenous or recombinant proteases, it is possible to delineate the roles of specific enzymes within larger signaling or degradation pathways. This application supports the identification of protease substrates, the mapping of cleavage events, and the assessment of pathway regulation under different experimental conditions. The substrate's sensitivity and selectivity make it a powerful tool for unraveling intricate biochemical networks.

Quality Control in Enzyme Production: The robust and reproducible performance of H-D-Phe-Pip-Arg-pNA.2HCl makes it an essential reagent for quality control during the production and purification of proteolytic enzymes. Manufacturers and researchers employ it to verify enzyme activity, ensure batch-to-batch consistency, and monitor storage stability. The straightforward colorimetric assay format facilitates rapid and accurate assessment, supporting the reliable supply of high-quality enzymes for research, industrial, or diagnostic applications. By providing a direct measure of functional activity, this substrate underpins rigorous quality assurance protocols in enzyme-related workflows.

1. The effect of B-type allatostatin neuropeptides on crosstalk between the insect immune response and cold tolerance

2. Therapeutic potential of an intestinotrophic hormone, glucagon-like peptide 2, for treatment of type 2 short bowel syndrome rats with intestinal bacterial and fungal dysbiosis

3. Immune-awakening Saccharomyces-inspired nanocarrier for oral target delivery to lymph and tumors

4. Relatedness of antibodies to peptides containing homocitrulline or citrulline in patients with rheumatoid arthritis

5. The spatiotemporal control of signalling and trafficking of the GLP-1R