Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Yeast. 2001 May;18(7):585-95.

Carnitine-dependent metabolic activities in Saccharomyces cerevisiae: three carnitine acetyltransferases are essential in a carnitine-dependent strain.

Author information

  • 1Institute for Wine Biotechnology, University of Stellenbosch, Victoria Street, ZA-7600 Stellenbosch, South Africa.

Abstract

L-carnitine is required for the transfer of activated acyl-groups across intracellular membranes in eukaryotic organisms. In Saccharomyces cerevisiae, peroxisomal membranes are impermeable to acetyl-CoA, which is produced in the peroxisome when cells are grown on fatty acids as carbon source. In a reversible reaction catalysed by carnitine acetyltransferases (CATs), activated acetyl groups are transferred to carnitine to form acetylcarnitine which can be shuttled across membranes. Here we describe a mutant selection strategy that specifically selects for mutants affected in carnitine-dependent metabolic activities. Complementation of three of these mutants resulted in the cloning of three CAT encoding genes: CAT2, coding for the carnitine acetyltransferase associated with the peroxisomes and the mitochondria; YAT1, coding for the carnitine acetyltransferase, which is presumably associated with the outer mitochondrial membrane, and YER024w (YAT2), which encodes a third, previously unidentified carnitine acetyltransferase. The data also show that (a) L-carnitine and all three CATs are essential for growth on non-fermentable carbon sources in a strain with a disrupted CIT2 gene; (b) Yat2p contributes significantly to total CAT activity when cells are grown on ethanol; and that (c) the carnitine-dependent transfer of activated acetyl groups plays a more important role in cellular processes than previously realised.

Copyright 2001 John Wiley & Sons, Ltd.

PMID:
11329169
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Loading ...
    Write to the Help Desk