Biomaterial Database

Amplification of chromogenic staining of proteases within electrophoretic gels. 1989

R I Roth, and J Levin

Department of Laboratory Medicine, University of California, School of Medicine, San Francisco.

A method is described for amplification of bands generated by chromogenic substrates following their reaction with proteases within electrophoretic gels. Chromogenic substrates, consisting of synthetic peptides containing the chromophore 4-nitroaniline (paranitroaniline, PNA), are applied directly to the surface of agarose or acrylamide gels. Protease activity within the gel results in the enzymatic amidolysis of the chromogenic substrates, releasing free PNA. The yellow PNA chromogen is then derivatized by reaction with p-dimethylaminocinnamaldehyde (DACA) to form a purple Schiff base compound. The resultant complex has a significantly higher molar absorbancy than the original PNA chromogen, thus increasing the sensitivity for low levels of amidolytic activity. The derivatized chromogen is easily visualized for photography.

UI	MeSH Term	Description	Entries
D007202	Indicators and Reagents	Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)	Indicator,Reagent,Reagents,Indicators,Reagents and Indicators
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010447	Peptide Hydrolases	Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.	Peptidase,Peptidases,Peptide Hydrolase,Protease,Proteases,Proteinase,Proteinases,Proteolytic Enzyme,Proteolytic Enzymes,Esteroproteases,Enzyme, Proteolytic,Hydrolase, Peptide
D001779	Blood Coagulation Factors	Endogenous substances, usually proteins, that are involved in the blood coagulation process.	Clotting Factor,Coagulation Factors,Blood Coagulation Factor,Clotting Factors,Coagulation Factor,Coagulation Factor, Blood,Coagulation Factors, Blood,Factor, Coagulation,Factors, Coagulation,Factor, Blood Coagulation,Factor, Clotting,Factors, Blood Coagulation,Factors, Clotting
D004587	Electrophoresis, Agar Gel	Electrophoresis in which agar or agarose gel is used as the diffusion medium.	Electrophoresis, Agarose Gel,Agar Gel Electrophoresis,Agarose Gel Electrophoresis,Gel Electrophoresis, Agar,Gel Electrophoresis, Agarose
D006737	Horseshoe Crabs	An arthropod subclass (Xiphosura) comprising the North American (Limulus) and Asiatic (Tachypleus) genera of horseshoe crabs.	Crabs, Horseshoe,Limulus,Limulus polyphemus,Tachypleus,Xiphosura,Crab, Horseshoe,Horseshoe Crab,Xiphosuras
D000814	Aniline Compounds	Compounds that include the aminobenzene structure.	Phenylamine,Phenylamines,Anilines,Compounds, Aniline
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia