Abstract
The n-alkane-assimilating diploid yeast, Candida tropicalis, possesses two acetoacetyl-CoA thiolase (Thiolase I) isozymes encoded by one allele: peroxisomal and cytosolic Thiolase Is encoded by both CT-T1A and CT-T1B. To clarify the function of peroxisomal and cytosolic Thiolase Is, the site-directed mutation leading Thiolase I ΔC6 without a putative C-terminal peroxisomal targeting signal was introduced on CT-T1A locus in the ct-t1bΔ-null mutant. The C-terminus-truncated Thiolase I was active and solely present in the cytosol. Although the ct-t1aΔ/t1bΔ-null mutants showed mevalonate auxotrophy, the mutants having the C-terminus-truncated Thiolase I did not require mevalonate for growth, as did the strains having cytosolic Thiolase I. These results demonstrate that the presence of Thiolase I in the cytoplasm is indispensable for the sterol synthesis in this yeast. It is of greater interest that peroxisomal and cytosolic Thiolase I isozymes, products of the same genes, play different roles in the respective compartments, although further investigations will be necessary to analyze how to be sorted into peroxisomes and the cytosol.
| Original language | English |
|---|---|
| Pages (from-to) | 285-290 |
| Number of pages | 6 |
| Journal | Cell Biochemistry and Biophysics |
| Volume | 32 |
| Publication status | Published - 2000 |
| Externally published | Yes |
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Keywords
- 3-ketoacyl-CoA thiolase
- Acetoacetyl-CoA thiolase
- Candida tropicalis
- Cytosol
- Mevalonate
- Peroxisome
ASJC Scopus subject areas
- Biophysics
- Cell Biology
- Clinical Biochemistry
Cite this
Genetic Evaluation of Peroxisomal and Cytosolic Acetoacetyl-CoA Thiolase Isozymes in n-Alkane-Assimilating Diploid Yeast, Candida tropicalis. / Ueda, Mitsuyoshi; Kanayama, Naoki; Tanaka, Atsuo.
In: Cell Biochemistry and Biophysics, Vol. 32, 2000, p. 285-290.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Genetic Evaluation of Peroxisomal and Cytosolic Acetoacetyl-CoA Thiolase Isozymes in n-Alkane-Assimilating Diploid Yeast, Candida tropicalis
AU - Ueda, Mitsuyoshi
AU - Kanayama, Naoki
AU - Tanaka, Atsuo
PY - 2000
Y1 - 2000
N2 - The n-alkane-assimilating diploid yeast, Candida tropicalis, possesses two acetoacetyl-CoA thiolase (Thiolase I) isozymes encoded by one allele: peroxisomal and cytosolic Thiolase Is encoded by both CT-T1A and CT-T1B. To clarify the function of peroxisomal and cytosolic Thiolase Is, the site-directed mutation leading Thiolase I ΔC6 without a putative C-terminal peroxisomal targeting signal was introduced on CT-T1A locus in the ct-t1bΔ-null mutant. The C-terminus-truncated Thiolase I was active and solely present in the cytosol. Although the ct-t1aΔ/t1bΔ-null mutants showed mevalonate auxotrophy, the mutants having the C-terminus-truncated Thiolase I did not require mevalonate for growth, as did the strains having cytosolic Thiolase I. These results demonstrate that the presence of Thiolase I in the cytoplasm is indispensable for the sterol synthesis in this yeast. It is of greater interest that peroxisomal and cytosolic Thiolase I isozymes, products of the same genes, play different roles in the respective compartments, although further investigations will be necessary to analyze how to be sorted into peroxisomes and the cytosol.
AB - The n-alkane-assimilating diploid yeast, Candida tropicalis, possesses two acetoacetyl-CoA thiolase (Thiolase I) isozymes encoded by one allele: peroxisomal and cytosolic Thiolase Is encoded by both CT-T1A and CT-T1B. To clarify the function of peroxisomal and cytosolic Thiolase Is, the site-directed mutation leading Thiolase I ΔC6 without a putative C-terminal peroxisomal targeting signal was introduced on CT-T1A locus in the ct-t1bΔ-null mutant. The C-terminus-truncated Thiolase I was active and solely present in the cytosol. Although the ct-t1aΔ/t1bΔ-null mutants showed mevalonate auxotrophy, the mutants having the C-terminus-truncated Thiolase I did not require mevalonate for growth, as did the strains having cytosolic Thiolase I. These results demonstrate that the presence of Thiolase I in the cytoplasm is indispensable for the sterol synthesis in this yeast. It is of greater interest that peroxisomal and cytosolic Thiolase I isozymes, products of the same genes, play different roles in the respective compartments, although further investigations will be necessary to analyze how to be sorted into peroxisomes and the cytosol.
KW - 3-ketoacyl-CoA thiolase
KW - Acetoacetyl-CoA thiolase
KW - Candida tropicalis
KW - Cytosol
KW - Mevalonate
KW - Peroxisome
UR - http://www.scopus.com/inward/record.url?scp=0034571517&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034571517&partnerID=8YFLogxK
M3 - Article
VL - 32
SP - 285
EP - 290
JO - Cell Biochemistry and Biophysics
JF - Cell Biochemistry and Biophysics
SN - 1085-9195
ER -