Identification of peroxisomal acyl-CoA thioesterases in yeast and humans

• Published in: The Journal of biological chemistry Vol. 274; no. 14; pp. 9216 - 9223
• Main Authors: Jones, J.M. (The Johns Hopkins University School of Medicine, Baltimore, MD.), Nau, K, Geraghty, M.T, Erdmann, R, Gould, S.J
• Format: Journal Article
• Language: English
• Published: United States American Society for Biochemistry and Molecular Biology 02.04.1999
• Subjects: ACIDE OLEIQUE; ACIDO OLEICO; ACTIVIDAD ENZIMATICA; ACTIVITE ENZYMATIQUE; Amino Acid Sequence; AMINO ACID SEQUENCES; Base Sequence; CHEMICAL COMPOSITION; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; Consensus Sequence; CYTOPLASMIC ORGANELLES; DNA, Fungal - chemistry; ENZYMIC ACTIVITY; ESTERASAS; ESTERASE; ESTERASES; EXPRESION GENICA; EXPRESSION DES GENES; Fluorescent Antibody Technique, Indirect; GENBANK/AF124264; GENBANK/AF124265; GENE; GENE EXPRESSION; Gene Expression Regulation, Enzymologic - drug effects; GENERO HUMANO; GENES; GENETIC REGULATION; GENETICA; GENETICS; GENETIQUE; GENRE HUMAIN; Green Fluorescent Proteins; Humans; IMMUNOCYTOCHEMISTRY; IMMUNOLOGIE; IMMUNOLOGY; INMUNOLOGIA; Luminescent Proteins - genetics; MANKIND; Microbodies - enzymology; Microscopy, Fluorescence; MOLECULAR SEQUENCE DATA; NUCLEOTIDE SEQUENCE; OLEIC ACID; Oleic Acid - pharmacology; Open Reading Frames; ORGANITE CELLULAIRE; ORGANULOS CITOPLASMICOS; Palmitoyl-CoA Hydrolase - genetics; Palmitoyl-CoA Hydrolase - metabolism; PEROXISOMAL TARGETING SIGNAL; PEROXISOMES; PROMOTERS; RNA, Messenger - metabolism; SACCHAROMYCES CEREVISIAE; Saccharomyces cerevisiae - enzymology; Saccharomyces cerevisiae - genetics; SECUENCIA NUCLEOTIDICA; Sequence Alignment; SEQUENCE NUCLEOTIDIQUE; STRUCTURAL GENES; Thiolester Hydrolases - genetics; Thiolester Hydrolases - metabolism
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.274.14.9216

A computer-based screen of the Saccharomyces cerevisiae genome identified YJR019C as a candidate oleate-induced gene. YJR019C mRNA levels were increased significantly during growth on fatty acids, suggesting that it may play a role in fatty acid metabolism. The YJR019C product is highly similar to tesB, a bacterial acyl-CoA thioesterase, and carries a tripeptide sequence, alanine-lysine-phenylalanine COOH , that closely resembles the consensus sequence for type-1 peroxisomal targeting signals. YJR019C directed green fluorescence protein to peroxisomes, and biochemical studies revealed that YJR019C is an abundant component of purified yeast peroxisomes. Disruption of the YJR019C gene caused a significant decrease in total cellular thioesterase activity, and recombinant YJR019C was found to exhibit intrinsic acyl-CoA thioesterase activity of 6 units/mg. YJR019C also shared significant sequence similarity with hTE, a human thioesterase that was previously identified because of its interaction with human immunodeficiency virus-Nef in the yeast two-hybrid assay. We report here that hTE is also a peroxisomal protein, demonstrating that thioesterase activity is a conserved feature of peroxisomes. We propose that YJR019C and hTE be renamed as yeast and human PTE1 to reflect the fact that they encode peroxisomal thioesterases. The physical segregation of yeast and human PTE1 from the cytosolic fatty acid synthase suggests that these enzymes are unlikely to play a role in formation of fatty acids. Instead, the observation that PTE1 contributes to growth on fatty acids implicates this thioesterase in fatty acid oxidation.