ABSTRACT
Caffeic acid (CA; 3,4-dihydroxycinnamic acid) is an aromatic compound obtained by the phenylpropanoid pathway. This natural product has antioxidant, antitumor, antiviral, and anti-inflammatory activities. It is also a precursor of CA phenethyl ester (CAPE), a compound with potential as an antidiabetic and liver-protective agent. CA can be found at low concentrations in plant tissues, and hence, its purification is difficult and expensive. Knowledge regarding the pathways, enzymes, and genes involved in CA biosynthesis has paved the way for enabling the design and construction of microbial strains with the capacity of synthesizing this metabolite. In this review, metabolic engineering strategies for the generation of Escherichia coli strains for the biotechnological production of CA are presented and discussed.
Subject(s)
Caffeic Acids/metabolism , Escherichia coli/metabolism , Metabolic Engineering/methods , Biological Products , Biotechnology , Coumaric AcidsABSTRACT
Background: The plant secondary metabolite pinosylvin is a polyphenol from the stilbene family, which have positive effects on human health. Biotechnological production is an attractive alternative for obtaining this stilbene. In Escherichia coli, malonyl-CoA is the precursor for both stilbene and fatty acid syntheses. In this study, with the aim of increasing pinosylvin production, we evaluated a novel approach that is based on reducing the expression of the gene fabI, which encodes the enzyme enoyl-acyl carrier protein reductase that is involved in fatty acid synthesis. Results: A recombineering method was employed to eliminate the chromosomal -35 promoter sequence and the upstream region of the gene fabI in E. coli strain W3110. Analysis, employing RT-qPCR, showed that such modification caused a 60% reduction in the fabI transcript level in the mutant strain W3110Δ-35fabI::Cm compared to the wild type W3110. Synthetic genes encoding a mutant version of 4-coumaroyl-CoA ligase from Streptomyces coelicolor A3 with improved catalytic activity employing cinnamic acid as substrate and a stilbene synthase from Vitis vinifera were cloned to generate the plasmid pTrc-Sc4CL(M)-VvSTS. The production performance of strains W3110Δ-35fabI::Cm/pTrc-Sc4CL(M)-VvSTS and W3110/pTrc-Sc4CL(M)- VvSTS was determined in shake flask cultures with Luria-Bertani medium supplemented with 10 g/L glycerol and 3 mM cinnamic acid. Under these conditions, the strain W3110Δ-35fabI::Cm/pTrc-Sc4CL(M)-VvSTS produced 52.67 mg/L pinosylvin, a level 1.5-fold higher than that observed with W3110/pTrc-Sc4CL(M)-VvSTS. Conclusion: A reduction in the transcript level of fabI caused by the elimination of the -35 and upstream promoter sequences is a successful strategy to improve pinosylvin production in E. coli.
Subject(s)
Stilbenes/metabolism , Escherichia coli/metabolism , Enoyl-(Acyl-Carrier-Protein) Reductase (NADH)/genetics , Biological Products , Coenzyme A Ligases , Fatty Acids , Metabolic EngineeringABSTRACT
El potencial de las cepas fúngicas en biorremediación, que han sido aisladas en el Instituto de Investigaciones Fármaco Bioquímicas (IIFB), es bastante amplio, se han encontrado cepas que han sido usadas en investigaciones a nivel internacional, tal es el caso de Bjerkandera sp BOL 13, un hongo aislado en un efluente contaminado con aceite en Oruro, con capacidad de degradar varios compuestos hidrocarbonados aromáticos policíclicos. En otro extremo de la nación se logró aislar Galerina sp., un hongo productor de lacasas, enzima importante en los procesos de decoloración.
The potential of fungi strains in biorremdiation that have been isolated in the Intiture of Research Pharmaceutical and Buiochemical (IIFB) is broad, it have been found strains that have been used in research at international level, as Bjerkandera sp BOL 13, a fungi isolated in an oil contaminated effluent, able to degrade polycycloic aromatic hydrocarbons. In other side of the country Galerina sp. was isolated, a laccase producing fungi, an enzyme important in decolorizing processes. contaminado con aceite en Oruro, con capacidad de degradar varios compuestos hidrocarbonados aromáticos policíclicos.
Subject(s)
Laccase , Research , Fungi , Hydrocarbons, AromaticABSTRACT
Las Bacterias Sulfato Reductoras (BSR) son responsables de la producción de sulfuro de hidrógeno (H2S) en anaerobiosis a partir de sulfatos y un donador de electrones. El sulfuro producido podría utilizarse para precipitar metales catiónicos divalentes,permitiendo la biorremediación de efluentes contaminados. El presente estudio forma parte del proyecto: Biodiversidad Microbiana del programa UMSA-SAREC con cooperación del departamento deBiotecnología de la Universidad de Lund y establece la posibilidad de montar biorreactores en el altiplano Boliviano para generar H2S. En el trabajo, seutilizó paja de trigo (donador de electrones) y consorcio bacteriano A10 (BSR) obtenido de la laguna ChalviriPotosí. Bajo condiciones de cultivo batch, se obtuvo una concentración de H2S entre 5 y 8 mM, y en condiciones de cultivo continuo una concentración de25 mM a los 100 días, concentraciones similares se sostuvieron por 90 días, lo que hace este modelo prometedor para su aprovechamiento a escala industrial.