Universität zu Köln

Teutschbein, Jenny, Gross, Wiltrud, Nimtz, Manfred, Milkowski, Carsten ORCID: 0000-0001-9758-6789, Hause, Bettina and Strack, Dieter (2010). Identification and Localization of a Lipase-like Acyltransferase in Phenylpropanoid Metabolism of Tomato (Solanum lycopersicum). J. Biol. Chem., 285 (49). S. 38374 - 38382. BETHESDA: AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC. ISSN 1083-351X

Full text not available from this repository.

Abstract

We have isolated an enzyme classified as chlorogenate: glucarate caffeoyltransferase (CGT) from seedlings of tomato (Solanum lycopersicum) that catalyzes the formation of caffeoylglucarate and caffeoylgalactarate using chlorogenate (5-O-caffeoylquinate) as acyl donor. Peptide sequences obtained by trypsin digestion and spectrometric sequencing were used to isolate the SlCGT cDNA encoding a protein of 380 amino acids with a putative targeting signal of 24 amino acids indicating an entry of the SlCGT into the secretory pathway. Immunogold electron microscopy revealed the localization of the enzyme in the apoplastic space of tomato leaves. Southern blot analysis of genomic cDNA suggests that SlCGT is encoded by a single-copy gene. The SlCGT cDNA was functionally expressed in Nicotiana benthamiana leaves and proved to confer chlorogenate-dependent caffeoyltransferase activity in the presence of glucarate. Sequence comparison of the deduced amino acid sequence identified the protein unexpectedly as a GDSL lipase-like protein, representing a new member of the SGNH protein superfamily. Lipases of this family employ a catalytic triad of Ser-Asp-His with Ser as nucleophile of the GDSL motif. Site-directed mutagenesis of each residue of the assumed respective SlCGT catalytic triad, however, indicated that the catalytic triad of the GDSL lipase is not essential for SlCGT enzymatic activity. SlCGT is therefore the first example of a GDSL lipase-like protein that lost hydrolytic activity and has acquired a completely new function in plant metabolism, functioning in secondary metabolism as acyltransferase in synthesis of hydroxycinnamate esters by employing amino acid residues different from the lipase catalytic triad.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Teutschbein, Jenny UNSPECIFIED UNSPECIFIED UNSPECIFIED Gross, Wiltrud UNSPECIFIED UNSPECIFIED UNSPECIFIED Nimtz, Manfred UNSPECIFIED UNSPECIFIED UNSPECIFIED Milkowski, Carsten UNSPECIFIED orcid.org/0000-0001-9758-6789 UNSPECIFIED Hause, Bettina UNSPECIFIED UNSPECIFIED UNSPECIFIED Strack, Dieter UNSPECIFIED UNSPECIFIED UNSPECIFIED
URN:	urn:nbn:de:hbz:38-490838
DOI:	10.1074/jbc.M110.171637
Journal or Publication Title:	J. Biol. Chem.
Volume:	285
Number:	49
Page Range:	S. 38374 - 38382
Date:	2010
Publisher:	AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
Place of Publication:	BETHESDA
ISSN:	1083-351X
Language:	English
Faculty:	Unspecified
Divisions:	Unspecified
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language CARBOXYPEPTIDASE-LIKE ACYLTRANSFERASES; HYDROXYCINNAMIC ACID-ESTERS; GERMINATED SUNFLOWER SEEDS; CHLOROGENIC ACID; GLUCARIC ACID; ENZYMATIC-SYNTHESIS; HYDROAROMATIC ACIDS; PROTEIN PREPARATION; EXPRESSION SYSTEM; GENE-EXPRESSION Multiple languages Biochemistry & Molecular Biology Multiple languages
URI:	http://kups.ub.uni-koeln.de/id/eprint/49083