The physical state of lipid substrates provides transacylation specificity for tafazzin.
Nat Chem Biol
; 8(10): 862-9, 2012 Oct.
Article
en En
| MEDLINE
| ID: mdl-22941046
ABSTRACT
Cardiolipin is a mitochondrial phospholipid with a characteristic acyl chain composition that depends on the function of tafazzin, a phospholipid-lysophospholipid transacylase, although the enzyme itself lacks acyl specificity. We incubated isolated tafazzin with various mixtures of phospholipids and lysophospholipids, characterized the lipid phase by (31)P-NMR and measured newly formed molecular species by MS. Substantial transacylation was observed only in nonbilayer lipid aggregates, and the substrate specificity was highly sensitive to the lipid phase. In particular, tetralinoleoyl-cardiolipin, a prototype molecular species, formed only under conditions that favor the inverted hexagonal phase. In isolated mitochondria, <1% of lipids participated in transacylations, suggesting that the action of tafazzin was limited to privileged lipid domains. We propose that tafazzin reacts with non-bilayer-type lipid domains that occur in curved or hemifused membrane zones and that acyl specificity is driven by the packing properties of these domains.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas de Drosophila
/
Metabolismo de los Lípidos
/
1-Acilglicerofosfocolina O-Aciltransferasa
Límite:
Animals
Idioma:
En
Revista:
Nat Chem Biol
Asunto de la revista:
BIOLOGIA
/
QUIMICA
Año:
2012
Tipo del documento:
Article
País de afiliación:
Estados Unidos