Development of a charcoal paper adenosine triphosphate:pyrophosphate exchange assay: kinetic characterization of NEDD8 activating enzyme.
Anal Biochem
; 394(1): 24-9, 2009 Nov 01.
Article
en En
| MEDLINE
| ID: mdl-19602421
ABSTRACT
Ubiquitin activating enzyme (UAE, UBE1, or E1) and seven known homologous "E1s" initiate the conjugation pathways for ubiquitin and 16 other ubiquitin-like modifiers (ULMs) found in humans. The initial step catalyzed by E1s uses adenosine triphosphate (ATP) to adenylate the C terminus of the appropriate ULM and results in the production of inorganic pyrophosphate (PPi). The mechanism of these enzymes can be studied with assays that measure the rate of ULM-dependent ATPPPi exchange. The traditional method follows the initial velocity of [32P]PPi incorporation into ATP by capturing the nucleotide on activated charcoal powder to separate it from excess [32P]PPi and then measuring [32P]ATP in a scintillation counter. We have modified the method by using charcoal paper to capture the nucleotide and a phosphorimager to quantify the [32P]ATP. The significant increase in throughput that these modifications provide is accomplished without any sacrifice in sensitivity or accuracy compared with the traditional method. To demonstrate this, we reproduce and extend the characterization of the NEDD8 activating enzyme.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Papel
/
Ubiquitinas
/
Adenosina Trifosfato
/
Carbón Orgánico
/
Difosfatos
/
Enzimas Activadoras de Ubiquitina
Límite:
Humans
Idioma:
En
Revista:
Anal Biochem
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos