Proteinase and Proteinase Activity Assays

Proteases are enzymes that hydrolyze proteins into smaller peptides or individual amino acids. Proteases play essential roles in biological processes, such as digestion, blood clotting, immune responses, and cell signaling. They work highly specific to amino acid sequences within a protein. This specificity allows for precise control over protein function and degradation (1, 2).

Chondrex, Inc., offers proteinase activity assay kits and enzymes for assaying the physiological activities of proteins involved in biological functions as well as protein manipulation and purification.

Proteinase Activity Assay Kits

	Product	Catalog #	Price (USD)
	Bacterial Collagenase Assay Kit	3014	433.00
	Cysteine Protease Activity Assay Kit	3101	355.00
	Rapid Collagenase Assay Kit with Type I Collagen Substrate	3001	535.00
	Rapid Collagenase Assay Kit with Type II Collagen Substrate	3002	535.00
	Trypsin Activity Assay Kit	3043	355.00

Proteinases

	Product	Catalog #	Price (USD)
	Elastase from Porcine Pancreas, 1 mg	30047	47.00
	Elastase from Porcine Pancreas, 10 mg	300471	423.00
	Papain	60224	22.00
	Pepsin	6011	14.00
	Recombinant Human MMP-8 (Full length, Latent Form) (BACK-ORDERED UNTIL FURTHER NOTICE)	5001	310.00
	Trypsin	30045	47.00

Proteinases

Proteinases are divided into 4 classes based upon specific residues found in their active sites. These classes of proteinases are aspartic proteinases, cysteine proteinases, metalloproteinases, and serine proteinases. The following are key examples, highlighting their specific functions and importance.

Collagenase: A family of metalloproteases that specifically target collagen in the body's connective tissues. Dysregulation of collagenase activity can contribute to various pathological conditions, such as arthritis and cancer metastasis (3)

Elastase: A serine protease released by neutrophils (a type of white blood cell), which plays a role in immune responses by degrading bacterial proteins and contributing to the formation of neutrophil extracellular traps (NETs)(4–6).

Papain: A cysteine protease involved in a wide range of cellular processes including protein degradation, antigen processing, and apoptosis (programmed cell death)(7).

Pepsin: An aspartic protease which preferentially cleaves peptide bonds where the amino acids phenylalanine, tyrosine, or tryptophan are present. Pepsin's primary function is to begin the digestion of proteins in the stomach. The products of pepsin digestion are larger peptides, which are further broken down by other proteases in the small intestine (8).

Trypsin: A serine protease which cleaves peptide bonds at specific sites, primarily where the amino acids lysine or arginine are present. It is secreted in its inactive form, trypsinogen, and is activated by enterokinase. It also activates other digestive enzymes, contributing to the overall process of nutrient absorption(5, 6).

Proteinase Inhibitors

Proteinase inhibitors control the activity of proteinases. Proteinases are grouped into four classes based on specific amino acids in their active sites. These classes are aspartic proteinases, cysteine proteinases, metalloproteinases, and serine proteinases. Proteinase inhibitors are generally divided into two categories: nonspecific inhibitors and class-specific inhibitors (2).

When measuring proteinase activity, selecting the right substrate is essential. Using the correct inhibitors in these assays is also crucial for accurate data, especially when samples contain multiple types of proteinases.

Proteinase inhibitors

References

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