Surface-entropy reduction used in the crystallization of human choline acetyltransferase.
Acta Crystallogr D Biol Crystallogr
; 61(Pt 9): 1306-10, 2005 Sep.
Article
em En
| MEDLINE
| ID: mdl-16131766
ABSTRACT
Human choline acetyltransferase (ChAT) synthesizes the neurotransmitter acetylcholine (ACh) from choline and acetyl-CoA. A crystal structure of human ChAT has been a long-standing goal in the neuronal signalling field. Milligram quantities of pure ChAT can be purified [Kim et al. (2005), Protein Expr. Purif. 40, 107-117], but exhaustive crystallization efforts failed to produce any crystals suitable for high-resolution structural studies. To obtain high-quality crystals of human ChAT, a truncation was made in a large poorly conserved loop region and high-entropy side chains were removed from the surface of the protein. The resulting 'entropy-reduced' ChAT (MR = 68.1 kDa) crystallizes readily and reproducibly and the crystals diffract X-rays to approximately 2.2 A. The availability of these crystals will allow us to study the structure of human ChAT on its own as well as in complex with its substrates and inhibitor molecules, leading to a greater understanding of its catalytic mechanism and regulation.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Colina O-Acetiltransferase
/
Entropia
/
Cristalização
Limite:
Humans
Idioma:
En
Revista:
Acta Crystallogr D Biol Crystallogr
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Canadá