Ligases, defined

Seol, J. H., et al., Cdc53/cullin and the essential Hrtl RING-H2 subunit of SCF define a ubiquitin ligase module that activates the E2 enzyme Cdc34. Genes Dev, 1999, 13(12), 1614-26. 

Seol, J. H., Feldman, R. M., Zachariae, W., Shevchenko, A., Correll, C. C., Lyapina, S., Chi, Y., Galova, M., Claypool, J., Sandmeyer, S., et al. (1999). Cdc53/cuUin and the essential Hrtl RING-H2 subunit of SCF define a ubiquitin ligase module that activates the E2 enzyme Cdc34, Genes Dev 13,1614-26. 

Terms in bold are defined in the cloning 306 vector 307 recombinant DNA 307 restriction endonucleases 307 DNA ligase 307 plasmid 311... 

Codon- A three-letter group (triplet) defining a specific amino acid in a protein. text cutters- restriction enzymes text splicers- DNA ligases... 

Note that there is an error in reference 6 in that the h2o is missing.) Ligase reactions necessarily involve coupling because they are defined (7) as "joining together of two molecules coupled with the hydrolysis of a pyrophosphate bond in atp of a similar triphosphate." This enzyme couples three hydrolase reactions ... 

EC nomenclature for enzymes A classification of ENZYMES according to the Enzyme Commission of the International Union of Biochemistry and Molecular Biology. Enzymes are allocated four numbers, the first of which defines the type of reaction catalyzed the next two define the substrates, and the fourth is a catalogue number. Categories of enzymes are EC 1, oxidoreduc-tases EC 2, transferases EC 3, hydrolases EC 4, lyases EC 5, isomerases EC 6, ligases (Synthetases). 

Entry into the S phase is defined by the Initiation of DNA replication. In S. cerevisiae cells this occurs when the Sid inhibitor is precipitously degraded following Its polyubiqui-tination by a distinct ubiquitin ligase called SCF (Figure... 

Fig. 12. Predicted domain organization and biosynthetic intermediates of the pimaricin synthase. Each circle represents an enzymatic domain as defined in Fig. 5. CoL, carboxylic acid CoA ligase. Continued)...

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