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Platform Chemicals (platform + chemical)
Selected AbstractsSelective and Flexible Transformation of Biomass-Derived Platform Chemicals by a Multifunctional Catalytic System,ANGEWANDTE CHEMIE, Issue 32 2010Frank Eine nachhaltige Versorgungskette: Die kontrollierte Überführung der aus Biomasse erhaltenen Plattformverbindungen Lävulinsäure (LA) und Itaconsäure (IA) in die entsprechenden Lactone, Diole oder cyclischen Ether (siehe Bild) wird durch einen multifunktionellen molekularen Katalysator möglich. [source] Platform chemicals from cropsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 11 2006Mairi Black First page of article [source] Metabolic engineering of Escherichia coli for the production of putrescine: A four carbon diamineBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2009Zhi-Gang Qian Abstract A four carbon linear chain diamine, putrescine (1,4-diaminobutane), is an important platform chemical having a wide range of applications in chemical industry. Biotechnological production of putrescine from renewable feedstock is a promising alternative to the chemical synthesis that originates from non-renewable petroleum. Here we report development of a metabolically engineered strain of Escherichia coli that produces putrescine at high titer in glucose mineral salts medium. First, a base strain was constructed by inactivating the putrescine degradation and utilization pathways, and deleting the ornithine carbamoyltransferase chain I gene argI to make more precursors available for putrescine synthesis. Next, ornithine decarboxylase, which converts ornithine to putrescine, was amplified by a combination of plasmid-based and chromosome-based overexpression of the coding genes under the strong tac or trc promoter. Furthermore, the ornithine biosynthetic genes (argC-E) were overexpressed from the trc promoter, which replaced the native promoter in the genome, to increase the ornithine pool. Finally, strain performance was further improved by the deletion of the stress responsive RNA polymerase sigma factor RpoS, a well-known global transcription regulator that controls the expression of ca. 10% of the E. coli genes. The final engineered E. coli strain was able to produce 1.68,g,L,1 of putrescine with a yield of 0.168,g,g,1 glucose. Furthermore, high cell density cultivation allowed production of 24.2,g,L,1 of putrescine with a productivity of 0.75,g,L,1,h,1. The strategy reported here should be useful for the bio-based production of putrescine from renewable resources, and also for the development of strains capable of producing other diamines, which are important as nitrogen-containing platform chemicals. Biotechnol. Bioeng. 2009; 104: 651,662 © 2009 Wiley Periodicals, Inc. [source] Platform biochemicals for a biorenewable chemical industryTHE PLANT JOURNAL, Issue 4 2008Basil J. Nikolau Summary The chemical industry is currently reliant on a historically inexpensive, petroleum-based carbon feedstock that generates a small collection of platform chemicals from which highly efficient chemical conversions lead to the manufacture of a large variety of chemical products. Recently, a number of factors have coalesced to provide the impetus to explore alternative renewable sources of carbon. Here we discuss the potential impact on the chemical industry of shifting from non-renewable carbon sources to renewable carbon sources. This change to the manufacture of chemicals from biological carbon sources will provide an opportunity for the biological research community to contribute fundamental knowledge concerning carbon metabolism and its regulation. We discuss whether fundamental biological research into metabolic processes at a holistic level, made possible by completed genome sequences and integrated with detailed structural understanding of biocatalysts, can change the chemical industry from being dependent on fossil-carbon feedstocks to using biorenewable feedstocks. We illustrate this potential by discussing the prospect of building a platform technology based upon a concept of combinatorial biosynthesis, which would explore the enzymological flexibilities of polyketide biosynthesis. [source] Green biorefinery demonstration plant in Havelland (Germany),BIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 3 2010Birgit Kamm Abstract The Green Biorefinery (GBR) is a complex and full-integrated system of environment- and resource-protecting technologies for comprehensive material and energetic use of green biomasses. GBR's are multiproduct systems and perform and produce in accordance with the physiology of the corresponding plant material preserving and using the diversity of the synthesis generated by nature. In addition to the general biorefinery concept, GBR's are based strongly on sustainable principles (sustainable land use, sustainable raw materials, gentle technologies, autarkic energy supply, etc.). Existing agricultural structures of the green crop processing industry, such as green crop drying plants, offer good opportunities for the implementation of biorefinery technologies that will help overcoming energy-intensive and partially obsolete technologies, such as the thermal drying of feedstock. Accordingly, the primary fractionation of green biomasses and the integrated production of proteins, fermentation media, animal feed, and biogas was projected and will be realized in a demonstration facility directly linked to the existing green crop drying plant, Selbelang, in Havelland (Germany, state Brandenburg, 50 km west of Berlin). The primary refinery will have an annual capacity of 20 000 tons alfalfa and grass biomass and can be diversified in modules for the production of platform chemicals and synthesis gas. We discuss the processes, products, operating costs and climate protection effects through examination of the basic engineering of the primary refinery. The production site and planned demonstration facility are also presented. Copyright © 2010 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Metabolic engineering of Escherichia coli for the production of putrescine: A four carbon diamineBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2009Zhi-Gang Qian Abstract A four carbon linear chain diamine, putrescine (1,4-diaminobutane), is an important platform chemical having a wide range of applications in chemical industry. Biotechnological production of putrescine from renewable feedstock is a promising alternative to the chemical synthesis that originates from non-renewable petroleum. Here we report development of a metabolically engineered strain of Escherichia coli that produces putrescine at high titer in glucose mineral salts medium. First, a base strain was constructed by inactivating the putrescine degradation and utilization pathways, and deleting the ornithine carbamoyltransferase chain I gene argI to make more precursors available for putrescine synthesis. Next, ornithine decarboxylase, which converts ornithine to putrescine, was amplified by a combination of plasmid-based and chromosome-based overexpression of the coding genes under the strong tac or trc promoter. Furthermore, the ornithine biosynthetic genes (argC-E) were overexpressed from the trc promoter, which replaced the native promoter in the genome, to increase the ornithine pool. Finally, strain performance was further improved by the deletion of the stress responsive RNA polymerase sigma factor RpoS, a well-known global transcription regulator that controls the expression of ca. 10% of the E. coli genes. The final engineered E. coli strain was able to produce 1.68,g,L,1 of putrescine with a yield of 0.168,g,g,1 glucose. Furthermore, high cell density cultivation allowed production of 24.2,g,L,1 of putrescine with a productivity of 0.75,g,L,1,h,1. The strategy reported here should be useful for the bio-based production of putrescine from renewable resources, and also for the development of strains capable of producing other diamines, which are important as nitrogen-containing platform chemicals. Biotechnol. Bioeng. 2009; 104: 651,662 © 2009 Wiley Periodicals, Inc. [source] | |||||||||||||