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The peroxisome proliferator-induced cytosolic type I Acyl-CoA thioesterase (CTE-I) is a serine-histidine-aspartic acid alpha/beta hydrolase

Huhtinen, K; O'Byrne, J; Lindquist, PJG; Contreras, Juan Antonio LU and Alexson, SEH (2002) In Journal of Biological Chemistry 277(5). p.3424-3432
Abstract
Long-chain acyl-CoA thioesterases hydrolyze longchain acyl-CoAs to the corresponding free fatty acid and CoASH and may therefore play important roles in regulation of lipid metabolism. We have recently cloned four members of a highly conserved acyl-CoA thioesterase multigene family expressed in cytosol (CTE-I), mitochondria (MTE-I), and peroxisomes (PTE-Ia and -Ib), all of which are regulated via the peroxisome proliferator-activated receptor a (Hunt, M. C., Nousiainen, S. E. B., Huttunen, M. K, Orii, K. E., Svensson, L. T., and Alexson, S. E. H. (1999) J. BioL Chem. 274,34317-34326). Sequence comparison revealed the presence of putative active-site serine motifs (GXSXG) in all four acyl-CoA thioesterases. In the present study we have... (More)
Long-chain acyl-CoA thioesterases hydrolyze longchain acyl-CoAs to the corresponding free fatty acid and CoASH and may therefore play important roles in regulation of lipid metabolism. We have recently cloned four members of a highly conserved acyl-CoA thioesterase multigene family expressed in cytosol (CTE-I), mitochondria (MTE-I), and peroxisomes (PTE-Ia and -Ib), all of which are regulated via the peroxisome proliferator-activated receptor a (Hunt, M. C., Nousiainen, S. E. B., Huttunen, M. K, Orii, K. E., Svensson, L. T., and Alexson, S. E. H. (1999) J. BioL Chem. 274,34317-34326). Sequence comparison revealed the presence of putative active-site serine motifs (GXSXG) in all four acyl-CoA thioesterases. In the present study we have expressed CTE-I in Escherichia coli and characterized the recombinant protein with respect to sensitivity to various amino acid reactive compounds. The recombinant CTE-I was inhibited by phenylmethylsulfonyl fluoride and diethyl pyrocarbonate, suggesting the involvement of serine and histidine residues for the activity. Extensive sequence analysis pinpointed Ser(232) ASp(324), and His(358) as the likely components of a catalytic triad, and site-directed mutagenesis verified the importance of these residues for the catalytic activity. A (SC)-C-232 mutant retained about 2% of the wild type activity and incubation with C-14-palmitoyl-CoA strongly labeled this mutant protein, in contrast to wild-type enzyme, indicating that deacylation of the acyl-enzyme intermediate becomes rate-limiting in this mutant protein. These data are discussed in relation to the structure/function of acyl-CoA thioesterases versus acyltransferases. Furthermore, kinetic characterization of recombinant CTE-I showed that this enzyme appears to be a true acyl-CoA thioesterase being highly specific for C-12-C-2, acyl-CoAs. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Biological Chemistry
volume
277
issue
5
pages
3424 - 3432
publisher
ASBMB
external identifiers
  • wos:000173688000050
  • pmid:11694534
  • scopus:0036479293
ISSN
1083-351X
DOI
10.1074/jbc.M109040200
language
English
LU publication?
yes
id
08166f2e-1fea-44b3-b85b-7213fca903e5 (old id 343853)
date added to LUP
2007-10-22 14:04:18
date last changed
2017-08-06 03:41:52
@article{08166f2e-1fea-44b3-b85b-7213fca903e5,
  abstract     = {Long-chain acyl-CoA thioesterases hydrolyze longchain acyl-CoAs to the corresponding free fatty acid and CoASH and may therefore play important roles in regulation of lipid metabolism. We have recently cloned four members of a highly conserved acyl-CoA thioesterase multigene family expressed in cytosol (CTE-I), mitochondria (MTE-I), and peroxisomes (PTE-Ia and -Ib), all of which are regulated via the peroxisome proliferator-activated receptor a (Hunt, M. C., Nousiainen, S. E. B., Huttunen, M. K, Orii, K. E., Svensson, L. T., and Alexson, S. E. H. (1999) J. BioL Chem. 274,34317-34326). Sequence comparison revealed the presence of putative active-site serine motifs (GXSXG) in all four acyl-CoA thioesterases. In the present study we have expressed CTE-I in Escherichia coli and characterized the recombinant protein with respect to sensitivity to various amino acid reactive compounds. The recombinant CTE-I was inhibited by phenylmethylsulfonyl fluoride and diethyl pyrocarbonate, suggesting the involvement of serine and histidine residues for the activity. Extensive sequence analysis pinpointed Ser(232) ASp(324), and His(358) as the likely components of a catalytic triad, and site-directed mutagenesis verified the importance of these residues for the catalytic activity. A (SC)-C-232 mutant retained about 2% of the wild type activity and incubation with C-14-palmitoyl-CoA strongly labeled this mutant protein, in contrast to wild-type enzyme, indicating that deacylation of the acyl-enzyme intermediate becomes rate-limiting in this mutant protein. These data are discussed in relation to the structure/function of acyl-CoA thioesterases versus acyltransferases. Furthermore, kinetic characterization of recombinant CTE-I showed that this enzyme appears to be a true acyl-CoA thioesterase being highly specific for C-12-C-2, acyl-CoAs.},
  author       = {Huhtinen, K and O'Byrne, J and Lindquist, PJG and Contreras, Juan Antonio and Alexson, SEH},
  issn         = {1083-351X},
  language     = {eng},
  number       = {5},
  pages        = {3424--3432},
  publisher    = {ASBMB},
  series       = {Journal of Biological Chemistry},
  title        = {The peroxisome proliferator-induced cytosolic type I Acyl-CoA thioesterase (CTE-I) is a serine-histidine-aspartic acid alpha/beta hydrolase},
  url          = {http://dx.doi.org/10.1074/jbc.M109040200},
  volume       = {277},
  year         = {2002},
}