Biochemical characterization of the vacuolar palmitoyl acyltransferase

FEBS Letters

Dietrich, Lars E.P²  Veit, Michael¹  Ungermann, Christian² 

[1] Department of Immunology and Molecular Biology, Vet.-Med. Faculty of the Free University Berlin, Philippstraße 13, 10115 Berlin, Germany;Biochemie-Zentrum Heidelberg, University of Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany

关键词: Vacuole fusion;    Vac8;    Palmitoylation;    SNARE complex;    Sec18;   

DOI  :  10.1016/S0014-5793(03)00232-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Vacuole fusion requires Sec18p-dependent acylation of the armadillo-repeat protein Vac8p that has been isolated with cis-SNARE complexes. To gain more insight into the mechanism of acylation, we analyzed the palmitoylation reaction on isolated vacuoles or in vacuolar detergent extracts. Recombinant Vac8p is palmitoylated when added to vacuoles and is anchored to membranes after modification. The palmitoyl acyltransferase (PAT) extracted from vacuolar membranes is functional in detergent extracts and shows all characteristics of an enzymatic activity: It modifies exogenous Vac8p in a temperature-, dose- and time-dependent manner, and is sensitive to bromo-palmitate, a known inhibitor of protein palmitoylation in vivo. Importantly, PAT is specific for palmitoyl-CoA, since myristoyl- and stearyl-CoA can compete with labeled Pal-CoA only at 10-fold higher amounts.

【 授权许可】

Unknown