Di-isodityrosine is the intermolecular cross-link of isodityrosine-rich extensin analogs cross-linked in vitro
| Autor: | Abdolreza Kamyab, Michael A. Held, Elena D. Shpak, Li Tan, Marcia J. Kieliszewski, Michael Hare |
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| Rok vydání: | 2004 |
| Předmět: |
Glycosylation
Magnetic Resonance Spectroscopy Time Factors Nicotiana tabacum Biochemistry Solanum lycopersicum Amino Acids Chromatography High Pressure Liquid Plant Proteins chemistry.chemical_classification Chromatography Extracellular Matrix Proteins biology Plants Genetically Modified Amino acid Hydroxyproline Cross-Linking Reagents Chromatography Gel Intercellular Signaling Peptides and Proteins Peroxidase Plasmids Recombinant Fusion Proteins Green Fluorescent Proteins Molecular Sequence Data Carbohydrates In Vitro Techniques Protein Sorting Signals Catalysis Hydrofluoric Acid Cell wall Tandem repeat Tobacco Amino Acid Sequence Molecular Biology Extensin Glycoproteins Base Sequence Lysine Cell Biology biology.organism_classification In vitro Culture Media chemistry Agrobacterium tumefaciens biology.protein Tyrosine Glycoprotein Carrier Proteins Peptides |
| Zdroj: | The Journal of biological chemistry. 279(53) |
| ISSN: | 0021-9258 |
| Popis: | Extensins are cell wall hydroxyproline-rich glycoproteins that form covalent networks putatively involving tyrosyl and lysyl residues in cross-links catalyzed by one or more extensin peroxidases. The precise cross-links remain to be chemically identified both as network components in muro and as enzymic products generated in vitro with native extensin monomers as substrates. However, some extensin monomers contain variations within their putative cross-linking motifs that complicate cross-link identification. Other simpler extensins are recalcitrant to isolation including the ubiquitous P3-type extensin whose major repetitive motif, Hyp)(4)-Ser-Hyp-Ser-(Hyp)(4)-Tyr-Tyr-Tyr-Lys, is of particular interest, not least because its Tyr-Tyr-Tyr intramolecular isodityrosine cross-link motifs are also putative candidates for further intermolecular cross-linking to form di-isodityrosine. Therefore, we designed a set of extensin analogs encoding tandem repeats of the P3 motif, including Tyr --Phe and Lys --Leu variations. Expression of these P3 analogs in Nicotiana tabacum cells yielded glycoproteins with virtually all Pro residues hydroxylated and subsequently arabinosylated and with likely galactosylated Ser residues. This was consistent with earlier analyses of P3 glycopeptides isolated from cell wall digests and the predictions of the Hyp contiguity hypothesis. The tyrosine-rich P3 analogs also contained isodityrosine, formed in vivo. Significantly, these isodityrosine-containing analogs were further cross-linked in vitro by an extensin peroxidase to form the tetra-tyrosine intermolecular cross-link amino acid di-isodityrosine. This is the first identification of an inter-molecular cross-link amino acid in an extensin module and corroborates earlier suggestions that di-isodityrosine represents one mechanism for cross-linking extensins in muro. |
| Databáze: | OpenAIRE |
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