Cysteine protease

cysteinecysteine peptidasecysteine endopeptidasecysteine proteasescysteine peptidasescysteine-cystein proteasescysteine proteinase inhibitors
Cysteine proteases, also known as thiol proteases, are enzymes that degrade proteins.wikipedia
211 Related Articles

Protease

proteasespeptidaseproteinase
These proteases share a common catalytic mechanism that involves a nucleophilic cysteine thiol in a catalytic triad or dyad.

Papain

Accuzymemeat tenderizerpapayotin
Papain, also known as papaya proteinase I, is a cysteine protease enzyme present in papaya (Carica papaya) and mountain papaya (Vasconcellea cundinamarcensis).

Calpain

calpains
A calpain is a protein belonging to the family of calcium-dependent, non-lysosomal cysteine proteases (proteolytic enzymes) expressed ubiquitously in mammals and many other organisms.

Cathepsin K

CTSKK
The protein encoded by this gene is a lysosomal cysteine protease involved in bone remodeling and resorption.

Catalytic triad

triadactive sitecatalytic tryad
These proteases share a common catalytic mechanism that involves a nucleophilic cysteine thiol in a catalytic triad or dyad.
Several families of cysteine proteases use this triad set, for example TEV protease and papain.

PA clan of proteases

PA clanPAPA superfamily
The clan contains both cysteine and serine proteases (different nucleophiles).

Thiol

mercaptansulfhydrylthiols
These proteases share a common catalytic mechanism that involves a nucleophilic cysteine thiol in a catalytic triad or dyad.
Active site cysteine residues are the functional unit in cysteine protease catalytic triads.

Protein superfamily

superfamilysuperfamiliesprotein fold
The MEROPS protease classification system counts 14 superfamilies plus several currently unassigned families (as of 2013) each containing many families.
The clan contains both cysteine and serine proteases (different nucleophiles).

TEV protease

Tobacco etch virus proteaseC3 protease
Several viruses (such as polio and hepatitis C) express their entire genome as a single massive polyprotein and use a protease to cleave it into functional units (for example, tobacco etch virus protease).
TEV protease (, Tobacco Etch Virus nuclear-inclusion-a endopeptidase) is a highly sequence-specific cysteine protease from Tobacco Etch Virus (TEV).

Apoptosis

apoptoticprogrammed cell deathcell death
In humans and other animals, they are responsible for senescence and apoptosis (programmed cell death), MHC class II immune responses, prohormone processing, and extracellular matrix remodeling important to bone development.
IAP also normally suppresses the activity of a group of cysteine proteases called caspases, which carry out the degradation of the cell.

Pyroglutamyl-peptidase I

EC 3.4.19.3pyroglutamyl peptidase
This cysteine peptidase is isolated from bacteria, plants and animals.

Inhibitor of apoptosis

IAPinhibitor of apoptosis proteinsantiapoptotic factor(s)
Many of these inhibitors act to block caspases, a family of cysteine proteases that play an integral role in apoptosis.

Aspartic protease

aspartyl proteaseaspartic proteasesaspartic proteinase
Proteases are usually synthesized as large precursor proteins called zymogens, such as the serine protease precursors trypsinogen and chymotrypsinogen, and the aspartic protease precursor pepsinogen.
Unlike serine or cysteine proteases these proteases do not form a covalent intermediate during cleavage.

Serpin

serine protease inhibitorSerpinsserine protease inhibitors
Some serpins inhibit other protease classes, typically cysteine proteases, and are termed "cross-class inhibitors".

Active site

catalytic domaincatalytic siteactive sites
Protease inhibitors are usually proteins with domains that enter or block a protease active site to prevent substrate access.
Many enzymes including serine protease, cysteine protease, protein kinase and phosphatase evolved to form transient covalent bonds between them and their substrates to lower the activation energy and allow the reaction to occur.

Serine protease

serine proteasesserineserine endopeptidase
Proteases are usually synthesized as large precursor proteins called zymogens, such as the serine protease precursors trypsinogen and chymotrypsinogen, and the aspartic protease precursor pepsinogen.

Proteolysis

proteolyticprotein degradationpolyprotein
Several viruses (such as polio and hepatitis C) express their entire genome as a single massive polyprotein and use a protease to cleave it into functional units (for example, tobacco etch virus protease).

Protease inhibitor (biology)

protease inhibitorprotease inhibitorsproteinase inhibitor
Inhibitor family I42 includes chagasin, a reversible inhibitor of papain-like cysteine proteases.

Enzyme

enzymologyenzymesenzymatic
Cysteine proteases, also known as thiol proteases, are enzymes that degrade proteins.

Protein

proteinsproteinaceousstructural proteins
Cysteine proteases, also known as thiol proteases, are enzymes that degrade proteins.

Catalysis

catalyzescatalysescatalyst
These proteases share a common catalytic mechanism that involves a nucleophilic cysteine thiol in a catalytic triad or dyad.

Nucleophile

nucleophilicnucleophilic attacknucleophilicity
These proteases share a common catalytic mechanism that involves a nucleophilic cysteine thiol in a catalytic triad or dyad.

Cysteine

CysL-cysteinecystein
These proteases share a common catalytic mechanism that involves a nucleophilic cysteine thiol in a catalytic triad or dyad.

Fruit

fruitsfruitingfresh fruit
Cysteine proteases are commonly encountered in fruits including the papaya, pineapple, fig and kiwifruit.