TERMIUM Plus^®

Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 DEF

Distinct polypeptide chain in which lies the domain accommodating the catalytic site of complex enzymes. It is completely separated from the domain building up the binding site for the regulatory effector(s). From an evolutionary viewpoint, it is probable that gene fusion did occur in most cases rather than that originally continuous polypeptide chains have separated. In some oligomeric enzymes the allosteric site may have appeared as a result of gene duplication, e. g. in glutamate dehydrogenase and glyceraldehyde-3-phosphate dehydrogenase, whereas in others by acquisition of a foreign structural gene, e. g. the NAD-binding domain in glycogen phosphorylase. However, in present day complex enzymes the catalytic and regulatory protein units remained separate, but associable, entities.  2, record 1, English, - catalytic%20subunit

Record number: 1, Textual support number: 1 CONT

The ATCase of E. coli has ... a molecular weight of about 310,000 but can be dissociated by treatment with mercurial reagents to yield two identical catalytic subunits and three identical regulatory subunits. Each of the two catalytic subunits has a molecular weight of about 100,000 and contains three polypeptide chains of molecular weight 34,000 called C chains. Each catalytic subunit contains three binding sites for the substrate aspartate, one on each of the three C chains. The catalytic subunits have enzymatic activity but are not sensitive to the modulator CTP.  3, record 1, English, - catalytic%20subunit

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

Lorsque la molécule native d'ATCase est dissociée en un mélange de ses sous-unités catalytiques et régulatrices, ce mélange fait toujours montre d'activité catalytique, mais la réaction n'est pas inhibée par le CTP tant que les sous-unités catalytiques et régulatrices sont séparées les unes des autres. Pour que l'inhibition par le CTP puisse avoir lieu, il faut que les sous-unités catalytiques et régulatrices soient physiquement associées dans la molécule oligomérique d'ATCase intacte.  1, record 1, French, - sous%2Dunit%C3%A9%20catalytique

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 DEF

General term for an enzyme transferring an inorganic phosphate group to some organic acceptor, hence belonging to the transferases.  2, record 2, English, - phosphorylase

Record number: 2, Textual support number: 1 CONT

Some enzymes may exist in two forms of different activity which are interconvertible. Frequently, the mechanism of interconversion consists of phosphorylation.... One of the best known cases is glycogen phosphorylase, the enzyme that degrades glycogen into its glucose units, and which exists in two forms : a and b. Phosphorylase a is a tetrameric protein having the higher activity; phosphorylase b is a less active dimer. The b form can be converted into the a form by the convalent binding of four phosphate groups.  3, record 2, English, - phosphorylase

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 DEF

Toute enzyme qui catalyse la phosphorolyse d'un composé par l'acide phosphorique.  2, record 2, French, - phosphorylase

Record number: 2, Textual support number: 1 CONT

Le glycogène est dégradé par phosphorolyse. Ceci signifie que le glycogène subit des coupures au niveau des restes de glucose, non pas hydrolytiques (avec fixation d'une molécule d'eau), mais phosphorolytiques (fixation d'une molécule d'acide phosphorique). Cette réaction est catalysée par une enzyme, la phosphorylase, enzyme très complexe (Cori, Sutherland) qui a été préparée à partir du foie et du muscle. Les enzymes des deux origines sont d'ailleurs de structure très différente.  3, record 2, French, - phosphorylase

Record 2,  Textual support,  Spanish

Record number: 2, Textual support number: 1 DEF

Enzimas de la clase transferasa, que catalizan la escisión de enlaces mediante la adición de fosfato inorgánico.  2, record 2, Spanish, - fosforilasa

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 OBS

A nonreducing dextrin obtained by the exhaustive action of an enzyme(as beta-amylase on amylopectin, or phosphorylase on glycogen). Webster  1, record 3, English, - residual%20dextrin

Record 3,  Textual support,  French

Record number: 3, Textual support number: 1 OBS

Portion d'un empois d'amidon ne fermentant que très lentement sous l'action d'un extrait de malt. Duval, Duval et Dolique, Dictionnaire de la chimie  1, record 3, French, - dextrine%20r%C3%A9siduelle

Record 3,  Textual support,  Spanish