Rekombinante Biosynthese amino-substituierter Phenylpropanoide in E. coli

Aromatic compounds and olefins are important precursors for chemical syntheses. The main source for these substances are the refining processes of crude oil. Driven by political, economical and ecological reasons the research in crude oil alternatives and therefore the utilisation of renewable resources gained particular importance. The objective is the biotechnological and chemical generation of adequate substitutes for important compounds but also of other substances that are currently only inefficiently synthesised. The recombinant biosynthesis of amino-substituted phenylpropanoids in E. coli aims at the production of p-aminocinnamyl alcohol. This aromatic alcohol is a novel compound with several functional groups and it has significant similarity to the naturally occurring monolignol p-coumaryl alcohol. Unlike this substance there is no existing pathway known for the biosynthesis of the derivate in natura. The approach to design an artificial pathway for p-aminocinnamyl alcohol is based on the combination of different reactions from the biosynthetic pathways for chloramphenicol, phenylpropanoids and lignin. It was shown that genetically modified E. coli cells can synthesise p-aminophenylalanine from endogenously available chorismate by using 4-amino-4-deoxychorismate synthase from Corynebacterium glutamicum and Streptomyces venezuelae 4-amino-4-deoxychorismate mutase and 4-amino-4-deoxyprephenate dehydrogenase. The uncommon, non-proteinogenic amino acid can undergo reactions of phenylpropanoid and lignin biosynthesis alike the natural substrate tyrosine. The deamination by Rhodobacter sphaeroides tyrosine ammonia-lyase or Zea mays phenylalanine ammonia-lyase to p-aminocinnamic acid is followed by the coenzyme A mediated activation by 4-coumarate:CoA ligase (Petroselinum crispum). p-Aminocinnamyl-CoA is a substrate for Zea mays cinnamyl-CoA reductase and the resulting aldehyde is converted by Zea mays cinnamyl alcohol dehydrogenase to the target product. Subsequently it is exported into the culture medium. Additionally, a short cut was identified that – simply by the activity of CoA ligase and reductase – efficiently converts the acid into the alcohol. All seven transgenes were functionally expressed in E. coli. It is the simultaneous abundance of all proteins that allows for the biosynthesis of p-aminocinnamyl alcohol without feeding any direct precursors. This demonstrates that complex artificial syntheses can be established by the way of biotechnological methods. The availability of this novel aromate permits new processing such as the polymerisation to novel thermoplasts with so far unknown functions.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2009

Author dc:creator

• Gilleßen, Bernhard

Contributors dc:contributor

• Kreuzaler, Fritz

• info:eu-repo/classification/ddc/570
• Biosynthese
• Lignin
• Escherichia coli
• Biotechnologie
• Biotechnologische Industrie
• Biokonversion
• Arylaldehyde
• Aromaten
• Arylalkohole
• Biowissenschaften, Biologie
• biosynthesis
• aromate
• biotechnology

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-113992%22

OAI record oai:identifier

https://publications.rwth-aachen.de/oai2d?verb=GetRecord&metadataPrefix=oai_dc&identifier=oai%3Apublications.rwth-aachen.de%3A51732