Efficient biotransformation of isoeugenol to vanillin in recombinant strains of Escherichia coli by using engineered isoeugenol monooxygenase and sol-gel chitosan membrane

2018 ◽  
Vol 71 ◽  
pp. 76-81 ◽  
Author(s):  
Liqing Zhao ◽  
Yingmiao Xie ◽  
Liuyan Chen ◽  
Xuefeng Xu ◽  
Cindy Xinxin Zhao ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Sol Gel ◽  
Recombinant Strains ◽  
Chitosan Membrane ◽  
Isoeugenol Monooxygenase

scholarly journals Isolation of a Gene Responsible for the Oxidation oftrans-Anethole topara-Anisaldehyde by Pseudomonas putida JYR-1 and Its Expression in Escherichia coli

2012 ◽  
Vol 78 (15) ◽  
pp. 5238-5246 ◽  
Author(s):  
Dongfei Han ◽  
Ji-Young Ryu ◽  
Robert A. Kanaly ◽  
Hor-Gil Hur
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Putida ◽  
Hypothetical Protein ◽  
Aldehyde Group ◽  
Agrobacterium Vitis ◽  
T7 Promoter ◽  
Content Type ◽  
E Coli ◽  
Cell Extracts ◽  
Isoeugenol Monooxygenase

ABSTRACTA plasmid, pTA163, inEscherichia colicontained an approximately 34-kb gene fragment fromPseudomonas putidaJYR-1 that included the genes responsible for the metabolism oftrans-anethole to protocatechuic acid. Three Tn5-disrupted open reading frame 10 (ORF 10) mutants of plasmid pTA163 lost their abilities to catalyzetrans-anethole. Heterologously expressed ORF 10 (1,047 nucleotides [nt]) under a T7 promoter inE. colicatalyzed oxidative cleavage of a propenyl group oftrans-anethole to an aldehyde group, resulting in the production ofpara-anisaldehyde, and this gene was designatedtao(trans-anetholeoxygenase). The deduced amino acid sequence of TAO had the highest identity (34%) to a hypothetical protein ofAgrobacterium vitisS4 and likely contained a flavin-binding site. Preferred incorporation of an oxygen molecule from water intop-anisaldehyde using18O-labeling experiments indicated stereo preference of TAO for hydrolysis of the epoxide group. Interestingly, unlike the narrow substrate range of isoeugenol monooxygenase fromPseudomonas putidaIE27 andPseudomonas nitroreducensJin1, TAO fromP. putidaJYR-1 catalyzed isoeugenol,O-methyl isoeugenol, and isosafrole, all of which contain the 2-propenyl functional group on the aromatic ring structure. Addition of NAD(P)H to the ultrafiltered cell extracts ofE. coli(pTA163) increased the activity of TAO. Due to the relaxed substrate range of TAO, it may be utilized for the production of various fragrance compounds from plant phenylpropanoids in the future.

scholarly journals 1D TiO2 Nanostructures Prepared from Seeds Presenting Tailored TiO2 Crystalline Phases and Their Photocatalytic Activity for Escherichia coli in Water

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Julieta Cabrera ◽  
Dwight Acosta ◽  
Alcides López ◽  
Roberto J. Candal ◽  
Claudia Marchi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Photocatalytic Activity ◽  
Bactericidal Activity ◽  
Sol Gel ◽  
Titanium Isopropoxide ◽  
E Coli ◽  
1D Nanostructures ◽  
Sol Gel Synthesis ◽  
Hydrolysis Of ◽  
Tio2 Nanostructures

TiO2 nanotubes were synthesized by alkaline hydrothermal treatment of TiO2 nanoparticles with a controlled proportion of anatase and rutile. Tailoring of TiO2 phases was achieved by adjusting the pH and type of acid used in the hydrolysis of titanium isopropoxide (first step in the sol-gel synthesis). The anatase proportion in the precursor nanoparticles was in the 3–100% range. Tube-like nanostructures were obtained with an anatase percentage of 18 or higher while flake-like shapes were obtained when rutile was dominant in the seed. After annealing at 400°C for 2 h, a fraction of nanotubes was conserved in all the samples but, depending on the anatase/rutile ratio in the starting material, spherical and rod-shaped structures were also observed. The photocatalytic activity of 1D nanostructures was evaluated by measuring the deactivation of E. coli in stirred water in the dark and under UV-A/B irradiation. Results show that in addition to the bactericidal activity of TiO2 under UV-A illumination, under dark conditions, the decrease in bacteria viability is ascribed to mechanical stress due to stirring.

Recombinant strains producing thermostable lipase from Thermomyces lanuginosus and their use in heterogeneous biocatalysis, including in the processes of low-temperature synthesis of esters

2021 ◽  
Vol 37 (5) ◽  
pp. 5-19
Author(s):  
M.B. Pykhtina ◽  
L.V. Perminova ◽  
G.A. Kovalenko
Keyword(s):  
Escherichia Coli ◽  
Fatty Acids ◽  
Pichia Pastoris ◽  
Substrate Specificity ◽  
Carbon Aerogel ◽  
Operational Stability ◽  
Thermomyces Lanuginosus ◽  
Thermostable Lipase ◽  
Recombinant Strains ◽  
Heterogeneous Biocatalysts

Abstract-This work was devoted to the construction of recombinant strains Escherichia coli BL21 (DE3) and Pichia pastoris X33, producing a 1,3-specific thermostable lipase from Thermomyces lanuginosus. The sequences of two lipase genes were optimized for expression in bacteria and methylotrophic yeasts, then synthesized and cloned into the corresponding expression vectors. As a result of genetic engineering manipulations, E. coli and P. pastoris strains were constructed that efficiently produced recombinant lipase from T. lanuginosus, which accumulated in the cytoplasm in an amount of 30-40% of the total cellular protein. Recombinant P. pastoris clones secreted lipase into the nutrient medium at a concentration of at least 1 g/L. Lipases produced by the recombinant clones, designated as rE.coli/lip and rPichia/lip, respectively, contained a six-histidine sequence (-His6) in the C-terminal region. The resulting lipases were immobilized on/in solid inorganic supports in order to develop heterogeneous biocatalysts (HB) for the enzymatic conversion of triglycerides and fatty acids. The rPichia/lip enzyme was adsorbed on mesoporous silica and macroporous carbon aerogel. The properties of the prepared HB, their enzymatic activity, substrate specificity and operational stability were studied in the reaction of esterification of fatty acids with aliphatic alcohols in organic solvents at 20 ± 2°C. It was found that immobilized lipases had a relatively wide substrate specificity, as well as high operational stability, and the prepared HB almost completely retained their high esterifying activity for several tens of reaction cycles. Key words: Escherichia coli, Pichia pastoris, recombinant strains-producers, Thermomyces lanuginosus lipase gene, immobilization, biocatalysts, esterification The authors are grateful to V. L. Kuznetsov for the provided samples of carbon aerogel and A. V. Ryabchenko for gene-engineering manipulation aimed at obtaining the recombinant rE. coli strain, a producer of the rE.coli/lip enzyme. The work was carried out under the Project on Fundamental Research within the framework of a state assignment to the Institute for Catalysis "Catalysts and Processes of Renewable Raw Material Conversion" (no. 0239-2021-0005).

Bioconversion of Substituted Naphthalenes to the Corresponding 1,2-Dihydroxy Derivatives by Escherichia coli Recombinant Strains

1997 ◽  
Vol 38 (35) ◽  
pp. 6267-6270 ◽  
Author(s):  
Patrizia Di Gennaro ◽  
Giuseppina Bestetti ◽  
Enrica Galli ◽  
Fulvia Orsini ◽  
Francesca Pelizzoni ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Recombinant Strains

scholarly journals Comparative Assessment of Antimicrobial Efficiency of Ionic Silver, Silver Monoxide, and Metallic Silver Incorporated onto an Aluminum Oxide Nanopowder Carrier

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Agnieszka Maria Jastrzębska ◽  
Ewa Karwowska ◽  
Andrzej R. Olszyna ◽  
Antoni R. Kunicki
Keyword(s):  
Escherichia Coli ◽  
Antibacterial Activity ◽  
Bacillus Subtilis ◽  
Aluminum Oxide ◽  
Sol Gel ◽  
Comparative Assessment ◽  
Metallic Silver ◽  
Gel Method ◽  
Ionic Silver ◽  
Antimicrobial Efficiency

The present paper provides comparative assessment of antimicrobial efficiency of ionic silver (Ag+), silver monoxide (Ag2O), and metallic silver (Ag) incorporated onto an aluminum oxide nanopowder carrier (Al2O3). The deposition of Ag+ ions, Ag2O nanoparticles, and Ag nanoparticles on an different phases of aluminum oxide nanopowder carrier was realized using consecutive stages of dry sol-gel method. The Al2O3-Ag+, Al2O3-Ag2O, and Al2O3-Ag nanopowders were widely characterized qualitatively and quantitatively by SEM, physical nitrogen sorption and XRD analyses. Results indicate that the Al2O3 nanopowders added with Ag+, Ag2O, and Ag, apart from phase composition, were not differing considerably from one another in terms of their morphology and physical properties. However, nanopowders of Al2O3-Ag were more agglomerated than Al2O3-Ag2O and Al2O3-Ag+ nanopowders. The antibacterial activity of the nanopowders was examined by the spread plate method using bacterial strains such as Escherichia coli, Sarcina lutea, and Bacillus subtilis. The best antibacterial properties against Sarcina lutea strain were achieved in the amorphous-Al2O3-Ag+ and Al2O3-Ag2O nanopowders, whereas the worst antimicrobial activity against Bacillus subtilis and Escherichia coli was shown by the Al2O3-Ag+ and Al2O3-Ag nanopowders. The observed increase of the antibacterial activity as the silver content was not however significant for Al2O3-Ag nanopowders. The results obtained in the present experiments show that the Al2O3-Ag+, Al2O3-Ag2O, and Al2O3-Ag nanopowders, possessing good bactericidal properties, can be produced by using consecutive stages of dry sol-gel method, and Al2O3 nanopowder added with Ag2O is considered as the best raw material in the production of antiseptic materials.

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