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1.
J Ethnopharmacol ; 308: 116273, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36822343

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Vitex rotundifolia L. f. and Vitex trifolia L. belong to the genus Vitex, and Vitex rotundifolia L. f. evolved from Vitex trifolia L. Both are essential ethnic medicinal plants with a long history, commonly used to treat headaches, fever, diarrhea, hair loss, wound recovery, and other diseases. AIM OF THE REVIEW: The research status of Vitex trifolia L. and its relative species Vitex rotundifolia L. f. were reviewed from the aspects of traditional medicinal use, phytochemistry, and pharmacological activities, to provide a reference for the further development and utilization of Vitex rotundifolia L. f. and Vitex trifolia L. MATERIALS AND METHODS: In this paper, a comprehensive search of published literature was conducted through various books and online databases to obtain relevant information on Vitex rotundifolia L. f. and Vitex trifolia L. The search terms "(Vitex rotundifolia) OR (Vitex trifolia) OR (Fructus viticis)" were entered in PubMed, Web of Science, China national knowledge infrastructure (CNKI), Wanfang Data, Baidu Scholar, respectively. In addition to setting the year threshold of "2018-2022" on Baidu Scholar, other databases searched all fields and found 889, 283, 1263, 1023, and 147 articles, respectively. Among them, review, repetition, overlapping data, and other reasons were excluded, and finally, a total of 164 articles were included in the review study. RESULTS: A total of 369 compounds have been identified, including 159 terpenoids, 51 flavonoids, 83 phenylpropanoids, and 76 other compounds. Pharmacological studies have shown that Vitex rotundifolia L. f. and Vitex trifolia L. have a variety of pharmacological activities, such as anti-tumor, analgesic, antipyretic, anti-inflammatory, antioxidant, antibacterial, and estrogen-like activity. Modern clinical use for treating cold headaches, diarrhea dysentery, irregular menstruation, and other diseases. CONCLUSIONS: As traditional medicinal plants, Vitex rotundifolia L. f. and Vitex trifolia L. have wealthy chemical constituents and extensive pharmacological activities and are widely used in clinical practice from traditional to modern times. However, the research on the pharmacological activities of Vitex rotundifolia L. f. and Vitex trifolia L. is not in-depth, and the potential active components still need to be explored.


Assuntos
Plantas Medicinais , Vitex , Vitex/química , Medicina Tradicional , Anti-Inflamatórios/farmacologia , China , Compostos Fitoquímicos , Etnofarmacologia , Extratos Vegetais/farmacologia
2.
PLoS One ; 17(12): e0278471, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36516154

RESUMO

Engineered bacteria could perform many functions in the environment, for example, to remediate pollutants, deliver nutrients to crops or act as in-field biosensors. Model organisms can be unreliable in the field, but selecting an isolate from the thousands that naturally live there and genetically manipulating them to carry the desired function is a slow and uninformed process. Here, we demonstrate the parallel engineering of isolates from environmental samples by using the broad-host-range XPORT conjugation system (Bacillus subtilis mini-ICEBs1) to transfer a genetic payload to many isolates in parallel. Bacillus and Lysinibacillus species were obtained from seven soil and water samples from different locations in Israel. XPORT successfully transferred a genetic function (reporter expression) into 25 of these isolates. They were then screened to identify the best-performing chassis based on the expression level, doubling time, functional stability in soil, and environmentally-relevant traits of its closest annotated reference species, such as the ability to sporulate and temperature tolerance. From this library, we selected Bacillus frigoritolerans A3E1, re-introduced it to soil, and measured function and genetic stability in a contained environment that replicates jungle conditions. After 21 months of storage, the engineered bacteria were viable, could perform their function, and did not accumulate disruptive mutations.


Assuntos
Bacillus subtilis , Conjugação Genética , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Solo , Israel
3.
Nat Mater ; 21(4): 471-478, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34857911

RESUMO

Engineered living materials could have the capacity to self-repair and self-replicate, sense local and distant disturbances in their environment, and respond with functionalities for reporting, actuation or remediation. However, few engineered living materials are capable of both responsivity and use in macroscopic structures. Here we describe the development, characterization and engineering of a fungal-bacterial biocomposite grown on lignocellulosic feedstocks that can form mouldable, foldable and regenerative living structures. We have developed strategies to make human-scale biocomposite structures using mould-based and origami-inspired growth and assembly paradigms. Microbiome profiling of the biocomposite over multiple generations enabled the identification of a dominant bacterial component, Pantoea agglomerans, which was further isolated and developed into a new chassis. We introduced engineered P. agglomerans into native feedstocks to yield living blocks with new biosynthetic and sensing-reporting capabilities. Bioprospecting the native microbiota to develop engineerable chassis constitutes an important strategy to facilitate the development of living biomaterials with new properties and functionalities.


Assuntos
Pantoea , Materiais Biocompatíveis , Humanos , Pantoea/química , Pantoea/genética
4.
Metab Eng ; 66: 308-318, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33460821

RESUMO

Achieving a high product titer through pathway optimization often requires screening many combinations of enzymes and genetic parts. Typically, a library is screened in a single chassis that is a model or production organism. Here, we present a technique where the library is first introduced into B. subtilis XPORT, which has the ability to transfer the DNA to many Gram-positive species using an inducible integrated conjugated element (ICE). This approach is demonstrated using a two-gene pathway that converts tyrosine to melanin, a pigment biopolymer that can serve as a protective coating. A library of 18 pathway variants is conjugated by XPORT into 18 species, including those isolated from soil and industrial contaminants. The resulting 324 strains are screened and the highest titer is 1.2 g/L in B. amyloliquefaciens BT16. The strains were evaluated as co-cultures in an industrial process to make mycelia-grown bulk materials, where the bacteria need to be productive in a stressful, spatially non-uniform and dynamic environment. B. subtilis BGSC 3A35 is found to perform well under these conditions and make melanin in the material, which can be seen visually. This approach enables the simultaneous screening of genetic designs and chassis during the build step of metabolic engineering.


Assuntos
Engenharia Metabólica , Biblioteca Gênica
5.
Adv Biochem Eng Biotechnol ; 162: 147-174, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28567487

RESUMO

Microbial polyhydroxyalkanoates (PHA) are a family of biodegradable and biocompatible polyesters which have been extensively studied using synthetic biology and metabolic engineering methods for improving production and for widening its diversity. Synthetic biology has allowed PHA to become composition controllable random copolymers, homopolymers, and block copolymers. Recent developments showed that it is possible to establish a microbial platform for producing not only random copolymers with controllable monomers and their ratios but also structurally defined homopolymers and block copolymers. This was achieved by engineering the genome of Pseudomonas putida or Pseudomonas entomophiles to weaken the ß-oxidation and in situ fatty acid synthesis pathways, so that a fatty acid fed to the bacteria maintains its original chain length and structures when incorporated into the PHA chains. The engineered bacterium allows functional groups in a fatty acid to be introduced into PHA, forming functional PHA, which, upon grafting, generates endless PHA variety. Recombinant Escherichia coli also succeeded in producing efficiently poly(3-hydroxypropionate) or P3HP, the strongest member of PHA. Synthesis pathways of P3HP and its copolymer P3HB3HP of 3-hydroxybutyrate and 3-hydroxypropionate were assembled respectively to allow their synthesis from glucose. CRISPRi was also successfully used to manipulate simultaneously multiple genes and control metabolic flux in E. coli to obtain a series of copolymer P3HB4HB of 3-hydroxybutyrate (3HB) and 4-hydroxybutyrate (4HB). The bacterial shapes were successfully engineered for enhanced PHA accumulation.


Assuntos
Escherichia coli , Genoma Bacteriano , Engenharia Metabólica/métodos , Poli-Hidroxialcanoatos , Pseudomonas putida/genética , Biologia Sintética/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Corpos de Inclusão/genética , Corpos de Inclusão/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Poli-Hidroxialcanoatos/genética
6.
Microb Biotechnol ; 10(2): 371-380, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27860284

RESUMO

Polylactide (PLA) is a bio-based plastic commonly synthesized by chemical catalytic reaction using lactic acid (LA) as a substrate. Here, novel LA-containing terpolyesters, namely, P[LA-co-3-hydroxybutyrate (3HB)-co-3-hydroxypropionate (3HP)], short as PLBP, were successfully synthesized for the first time by a recombinant Escherichia coli harbouring polyhydroxyalkanoate (PHA) synthase from Pseudomonas stutzeri (PhaC1Ps ) with 4-point mutations at E130D, S325T, S477G and Q481K, and 3-hydroxypropionyl-CoA (3HP-CoA) synthesis pathway from glycerol, 3-hydroxybutyryl-CoA (3HB-CoA) as well as lactyl-CoA (LA-CoA) pathways from glucose. Combining these pathways with the PHA synthase mutant phaC1Ps (E130D S325T S477G Q481K), the random terpolyester P(LA-co-3HB-co-3HP), or PLBP, was structurally confirmed by nuclear magnetic resonance to consist of 2 mol% LA, 90 mol% 3HB, and 8 mol% 3HP respectively. Remarkably, the PLBP terpolyester was produced from low-cost sustainable glycerol and glucose. Monomer ratios of PLBP could be regulated by ratios of glycerol to glucose. Other terpolyester thermal and mechanical properties can be manipulated by adjusting the monomer ratios. More PLBP applications are to be expected.


Assuntos
Aciltransferases/metabolismo , Escherichia coli/metabolismo , Engenharia Metabólica , Poliésteres/metabolismo , Pseudomonas stutzeri/enzimologia , Proteínas Recombinantes/metabolismo , Acil Coenzima A/metabolismo , Aciltransferases/genética , Custos e Análise de Custo , Escherichia coli/enzimologia , Escherichia coli/genética , Glucose/metabolismo , Glicerol/metabolismo , Espectroscopia de Ressonância Magnética , Redes e Vias Metabólicas/genética , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação de Sentido Incorreto , Mutação Puntual , Pseudomonas stutzeri/genética , Proteínas Recombinantes/genética
7.
Metab Eng ; 29: 189-195, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25842374

RESUMO

Poly(3-hydroxypropionate) (P3HP) is the strongest family member of microbial polyhydroxyalkanoates (PHA) synthesized by bacteria grown on 1,3-propandiol or glycerol. In this study synthesis pathways of P3HP and its copolymer P3HB3HP of 3-hydroxybutyrate (3HB) and 3-hydroxypropionate (3HP) were assembled respectively to allow their synthesis from glucose, a more abundant carbon source. Recombinant Escherichia coli was constructed harboring the P3HP synthetic pathway consisting of heterologous genes encoding glycerol-3-phosphate dehydrogenase (gpd1), glycerol-3-P phosphatase (gpp2) from Saccharomyces cerevisiae that catalyzes formation of glycerol from glucose, and genes coding glycerol dehydratase (dhaB123) with its reactivating factors (gdrAB) from Klebsiella pneumoniae that transfer glycerol to 3-hydroxypropionaldehyde, as well as gene encoding propionaldehyde dehydrogenase (pdup) from Salmonella typhimurium which converts 3-hydroxypropionaldehyde to 3-hydroxypropionyl-CoA, together with the gene of PHA synthase (phaC) from Ralstonia eutropha which polymerizes 3-hydroxypropionyl-CoA into P3HP. When phaA and phaB from Ralstonia eutropha respectively encoding ß-ketothiolase and acetoacetate reductase, were introduced into the above P3HP producing recombinant E. coli, copolymers poly(3-hydroxybutyrate-co-3-hydroxypropionate) (P3HB3HP) were synthesized from glucose as a sole carbon source. The above E. coli recombinants grown on glucose LB medium successfully produced 5g/L cell dry weight containing 18% P3HP and 42% P(3HB-co-84mol% 3HP), respectively, in 48h shake flask studies.


Assuntos
Proteínas de Bactérias , Cupriavidus necator/genética , Escherichia coli , Glucose/metabolismo , Hidroxibutiratos/metabolismo , Engenharia Metabólica , Poliésteres/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Cupriavidus necator/enzimologia , Escherichia coli/genética , Escherichia coli/metabolismo , Glucose/genética , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/biossíntese , Proteínas de Saccharomyces cerevisiae/genética
8.
Curr Opin Biotechnol ; 29: 24-33, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24632193

RESUMO

Many bacteria have been found to produce various polyhydroxyalkanoates (PHA) biopolyesters. In many cases, it is not easy to control the structures of PHA including homopolymers, random copolymers and block copolymers as well as ratios of monomers in the copolymers. It has become possible to engineer bacteria for controllable synthesis of PHA with the desirable structures by creating new PHA synthesis pathways. Remarkably, the weakening of ß-oxidation cycle in Pseudomonas putida and Pseudomonas entomophila led to controllable synthesis of all kinds of PHA structures including monomer ratios in random and/or block copolymers when fatty acids are used as PHA precursors. Introduction of functional groups into PHA polymer chains in predefined proportions has become a reality provided fatty acids containing the functional groups are taken up by the bacteria for PHA synthesis. This allows the formation of functional PHA for further grafting. The PHA diversity is further widened by the endless possibility of controllable homopolymerization, random copolymerization, block copolymerization and grafting on functional PHA site chains.


Assuntos
Bioengenharia , Poliésteres/metabolismo , Vias Biossintéticas , Oxirredução , Poliésteres/química , Poli-Hidroxialcanoatos , Pseudomonas/química , Pseudomonas/metabolismo
9.
Sci China Life Sci ; 57(1): 4-10, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24369356

RESUMO

Microbial synthesis of functional polymers has become increasingly important for industrial biotechnology. For the first time, it became possible to synthesize controllable composition of poly(3-hydroxyalkanoate) (P3HA) consisting of 3-hydroxydodecanoate (3HDD) and phenyl group on the side-chain when chromosome of Pseudomonas entomophila was edited to weaken its ß-oxidation. Cultured in the presence of 5-phenylvaleric acid (PVA), the edited P. entomophila produced only homopolymer poly(3-hydroxy-5-phenylvalerate) or P(3HPhV). While copolyesters P(3HPhV-co-3HDD) of 3-hydroxy-5-phenylvalerate (3HPhV) and 3-hydroxydodecanoate (3HDD) were synthesized when the strain was grown on mixtures of PVA and dodecanoic acid (DDA). Compositions of 3HPhV in P(3HPhV-co-3HDD) were controllable ranging from 3% to 32% depending on DDDA/PVA ratios. Nuclear magnetic resonance (NMR) spectra clearly indicated that the polymers were homopolymer of P(3HPhV) and random copolymers of 3HPhV and 3HDD. Their mechanical and thermal properties varied dramatically depending on the monomer ratios. Our results demonstrated the possibility to produce tailor-made, novel functional PHA using the chromosome edited P. entomophila.


Assuntos
Benzeno/análise , Genoma Bacteriano , Poli-Hidroxialcanoatos/química , Pseudomonas/metabolismo , Cromossomos Bacterianos , Meios de Cultura , Ressonância Magnética Nuclear Biomolecular , Poli-Hidroxialcanoatos/metabolismo , Pseudomonas/genética
10.
Biomacromolecules ; 14(3): 862-70, 2013 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-23351169

RESUMO

Poly(4-hydroxybutyrate) (P4HB) is a highly elastic polymer, whereas poly(3-hydroxypropionate) (P3HP) is a polymer with enormous tensile strength. This study aimed to biosynthesize a block copolymer consisting of soft P4HB block with a strong P3HP block to gain unique and excellent material properties. A recombinant Escherichia coli strain that produces homopolymers of P3HP and P4HB was employed for the block copolymer synthesis. When the strain was grown in the presence of 1,4-butanediol (BDO) as a 4HB precursor, P4HB block was formed. Sequential supplementation of 1,3-propanediol (PDO) as a 3HP precursor allowed the strain to produce P3HP block. Thermal, NMR, fractionation, and mechanical characterizations confirmed the resulting polymer as a block copolymer of P3HP-b-P4HB. Two block copolymers were formed from this study, including the P3HP-b-29% P4HB and P3HP-b-37% P4HB, they showed superior properties over random copolymers P(3HP-co-4HB). The block copolymers had two glass transition temperatures (Tg) and two melting temperatures (Tm). In comparison to the homopolymers P3HP and P4HB, incorporation of block microstructure resulted in the lowering of Tm, block copolymers were revealed with higher Young's modulus, yield strengths, and tension strengths much better than the previously reported random copolymers of similar compositions. Block copolymerization of P3HP and P4HB adds a new vision on PHA polymerization by generation of new polymers with superior properties.


Assuntos
Escherichia coli/metabolismo , Poliésteres/metabolismo , Polímeros/metabolismo , Butileno Glicóis/química , Espectroscopia de Ressonância Magnética , Peso Molecular , Poliésteres/isolamento & purificação , Propilenoglicóis/química , Temperatura
11.
Metab Eng ; 14(4): 317-24, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22561235

RESUMO

Copolyesters of 3-hydroxypropionate (3HP) and 4-hydroxybutyrate (4HB), abbreviated as P(3HP-co-4HB), was synthesized by Escherichia coli harboring a synthetic pathway consisting of five heterologous genes including orfZ encoding 4-hydroxybutyrate-coenzyme A transferase from Clostridium kluyveri, pcs' encoding the ACS domain of tri-functional propionyl-CoA ligase (PCS) from Chloroflexus aurantiacus, dhaT and aldD encoding dehydratase and aldehyde dehydrogenase from Pseudomonas putida KT2442, and phaC1 encoding PHA synthase from Ralstonia eutropha. When grown on mixtures of 1,3-propanediol (PDO) and 1,4-butanediol (BDO), compositions of 4HB in microbial P(3HP-co-4HB) were controllable ranging from 12 mol% to 82 mol% depending on PDO/BDO ratios. Nuclear magnetic resonance (NMR) spectra clearly indicated the polymers were random copolymers of 3HP and 4HB. Their mechanical and thermal properties showed obvious changes depending on the monomer ratios. Morphologically, P(3HP-co-4HB) films only became fully transparent when monomer 4HB content was around 67 mol%. For the first time, P(3HP-co-4HB) with adjustable monomer ratios were produced and characterized.


Assuntos
Engenharia Metabólica/métodos , Poliésteres/metabolismo , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/metabolismo , Butileno Glicóis/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Coenzima A-Transferases/genética , Coenzima A-Transferases/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Hidroliases/genética , Hidroliases/metabolismo , Propilenoglicóis/metabolismo
12.
Metab Eng ; 13(6): 777-85, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22024131

RESUMO

Conversion of 3-hydroxypropionate (3HP) from 1,3-propanediol (PDO) was improved by expressing dehydratase gene (dhaT) and aldehyde dehydrogenase gene (aldD) of Pseudomonas putida KT2442 under the promoter of phaCAB operon from Ralstonia eutropha H16. Expression of these genes in Aeromonas hydrophila 4AK4 produced up to 21 g/L 3HP in a fermentation process. To synthesize homopolymer poly(3-hydroxypropionate) (P3HP), and copolymer poly(3-hydroxypropionate-co-3-hydroxybutyrate) (P3HP4HB), dhaT and aldD were expressed in E. coli together with the phaC1 gene encoding polyhydroxyalkanoate (PHA) synthase gene of Ralstonia eutropha, and pcs' gene encoding the ACS domain of the tri-functional propionyl-CoA ligase (PCS) of Chloroflexus aurantiacus. Up to 92 wt% P3HP and 42 wt% P3HP4HB were produced by the recombinant Escherichia coli grown on PDO and a mixture of PDO+1,4-butanediol (BD), respectively.


Assuntos
Escherichia coli/metabolismo , Hidroxibutiratos/metabolismo , Ácido Láctico/análogos & derivados , Poliésteres/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Aeromonas hydrophila/genética , Aeromonas hydrophila/metabolismo , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/metabolismo , Biopolímeros/biossíntese , Butileno Glicóis/metabolismo , Chloroflexus/genética , Chloroflexus/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Cupriavidus necator/genética , Cupriavidus necator/metabolismo , Escherichia coli/genética , Fermentação , Engenharia Genética , Hidroliases/genética , Hidroliases/metabolismo , Ácido Láctico/biossíntese , Regiões Promotoras Genéticas , Propilenoglicóis/metabolismo , Pseudomonas putida/genética , Pseudomonas putida/metabolismo
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