Ligases


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Ligases

 

(or synthetases), a class of enzymes that catalyze the joining together of two molecules. They play an important role in the most significant anabolic processes—the biosynthesis of proteins, fats, and carbohydrates. Reactions catalyzed by ligases take place at the expense of energy released during the breakdown of adenosine triphosphate (ATP) or a similar triphosphate. The term “ligase” is also applied to synthesizing enzymes that act without the participation of nucleoside triphosphates.

References in periodicals archive ?
The so-called family of bacterial LPX-E3 ligases has been licenced.
Robinson, "E3 ubiquitin ligases," Essays in Biochemistry, vol.
Under the multi-year collaboration, Nurix will utilize its proprietary drug discovery platform to identify novel agents that utilise E3 ligases to induce degradation of specified drug targets and Gilead will have an option to license drug candidates directed to up to five targets resulting from the work.
Two genes encoding a regulatory enzyme known as E3 ubiquitin ligase were also found in qBBR11-1.
"We screened more than 600 proteins systematically and narrowed it down to 30 E3 ligases of special interest."
Shabek, "Ubiquitin ligases: structure, function, and regulation," Annual Review of Biochemistry, vol.
(2009) CBP and p300 are cytoplasmic E4 polyubiquitin ligases for p53.
The CIITA in vitro ubiquitination assay was carried out in 150 [micro]L of reaction mixture containing 40 mM Tris-HCL (pH 7.5), 5mM Mg[Cl.sub.2], 2mM dithiothreitol, 1mM Creatine Phosphate, 2mM ATP, 400 ng of Recombinant GST-CIITA (substrate), 400 ng of GSTHdm2 (Boston Biochem), 400 ng Recombinant His-pCAF (E3 ligase candidate) (Proteinone Rockville, MD), 500 ng Flag ubiquitin (Boston Biochem, Boston, MA), 200 ng E1 activating enzyme, UBE1 (Boston Biochem), 200 ng E2 conjugating enzyme, and UbcH5b (Boston Biochem).
However, the association of SUMO ligases and NF-[kappa]B signaling in DN has not been defined.
Nurix is likely to concentrate on investigating E3 ubiquitin ligases and E2 conjugating enzymes.
DNA ligases are enzymes that covalently join DNA strands by catalyzing the formation of a phosphodiester bond.
There are currently three main classes of E3 ligases, the really interesting new gene (RING) class, the homologous to the E6-AP carboxyl terminus (HECT) class, and the RING-between-RING (RBR) class, which catalyze ubiquitin ligation through very different mechanisms (extensively reviewed in [2]).