Momordin or α-momorcharin is one of several related protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

s isolated from several plants of the Momordica

Momordica

Momordica is a genus of about 60 species of annual or perennial climbers herbaceous or rarely small shrubs belonging to the family Cucurbitaceae, natives of tropical and subtropical Africa and Asia and Australia...

genus, which includes the bitter melon

Bitter melon

Momordica charantia, called bitter melon or bitter gourd in English, is a tropical and subtropical vine of the family Cucurbitaceae, widely grown in Asia, Africa, and the Caribbean for its edible fruit, which is among the most bitter of all fruits...

 (M. charantia) and the balsam apple

Balsam apple

Balsam apple may refer to:* Clusia major, a tree species found in America* Momordica balsamina, a vine species found in Africa* Bitter melon , a vine grown for its bitter and edible fruit...

 (M. balsamina).

These enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

s are potent inhibitor of protein synthesis in eukaryote

Eukaryote

A eukaryote is an organism whose cells contain complex structures enclosed within membranes. Eukaryotes may more formally be referred to as the taxon Eukarya or Eukaryota. The defining membrane-bound structure that sets eukaryotic cells apart from prokaryotic cells is the nucleus, or nuclear...

s by inactivating the ribosome

Ribosome

A ribosome is a component of cells that assembles the twenty specific amino acid molecules to form the particular protein molecule determined by the nucleotide sequence of an RNA molecule....

s. However its cytotoxic activity is limited because it is not taken up by the cells; it has to be chemically modified to do so.

There are several variants, including momordin II (from M. balsamina) and momordin-a (from M. charantia).

See also

• Momordin (saponin)
  Momordin (saponin)
  Momordin is one of several saponins derived from oleanolic acid, a triterpenoid. These chemical compounds are found in some plants of the Momordica genus, which includes the bitter melon and the balsam apple Momordin is one of several saponins derived from oleanolic acid, a triterpenoid. These...
  
  , an unrelated compound (a saponin
  Saponin
  Saponins are a class of chemical compounds, one of many secondary metabolites found in natural sources, with saponins found in particular abundance in various plant species...
  
   of the triterpenoid
  Triterpenoid
  Triterpenoids are terpenoid derviatives of triterpene molecules.They may have useful anti-cancer properties.Notable examples*Betulinic acid, possible anti-cancer drug*Bardoxolone methyl, inflammation modulator*Triterpenoid saponins...
  
   oleanic acid).