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1.
Enzyme Microb Technol ; 177: 110429, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38537325

RESUMO

Poly(ethylene furanoate) (PEF) plastic is a 100% renewable polyester that is currently being pursued for commercialization as the next-generation bio-based plastic. This is in line with growing demand for circular bioeconomy and new plastics economy that is aimed at minimizing plastic waste mismanagement and lowering carbon footprint of plastics. However, the current catalytic route for the synthesis of PEF is impeded with technical challenges including high cost of pretreatment and catalyst refurbishment. On the other hand, the semi-biosynthetic route of PEF plastic production is of increased biotechnological interest. In particular, the PEF monomers (Furan dicarboxylic acid and ethylene glycol) can be synthesized via microbial-based biorefinery and purified for subsequent catalyst-mediated polycondensation into PEF. Several bioengineering and bioprocessing issues such as efficient substrate utilization and pathway optimization need to be addressed prior to establishing industrial-scale production of the monomers. This review highlights current advances in semi-biosynthetic production of PEF monomers using consolidated waste biorefinery strategies, with an emphasis on the employment of omics-driven systems biology approaches in enzyme discovery and pathway construction. The roles of microbial protein transporters will be discussed, especially in terms of improving substrate uptake and utilization from lignocellulosic biomass, as well as from depolymerized plastic waste as potential bio-feedstock. The employment of artificial bioengineered microbial consortia will also be highlighted to provide streamlined systems and synthetic biology strategies for bio-based PEF monomer production using both plant biomass and plastic-derived substrates, which are important for circular and new plastics economy advances.

2.
NPJ Biofilms Microbiomes ; 9(1): 95, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38065982

RESUMO

The human microbiome has emerged as a key player in maintaining skin health, and dysbiosis has been linked to various skin disorders. Amidst growing concerns regarding the side effects of antibiotic treatments, the potential of live biotherapeutic products (LBPs) in restoring a healthy microbiome has garnered significant attention. This review aims to evaluate the current state of the art of the genetically or metabolically engineered LBPs, termed single-cell engineered LBPs (eLBPs), for skin repair and disease treatment. While some studies demonstrate promising outcomes, the translation of eLBPs into clinical applications remains a significant hurdle. Substantial concerns arise regarding the practical implementation and scalability of eLBPs, despite the evident potential they hold in targeting specific cells and delivering therapeutic agents. This review underscores the need for further research, robust clinical trials, and the exploration of current advances in eLBP-based bioengineered bacterial chassis and new outlooks to substantiate the viability and effectiveness of eLBPs as a transformative approach in skin repair and disease intervention.


Assuntos
Antibacterianos , Microbiota , Humanos , Pele
3.
MethodsX ; 11: 102434, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37846354

RESUMO

Polyhydroxyalkanoate (PHA)-producing bacteria represent a powerful synthetic biology chassis for waste bioconversion and bio-upcycling where PHAs can be produced as the final products. In this study, we present a seamless plasmid construction for orthogonal expression of recombinant PET hydrolase (PETase) in model PHA-producing bacteria P. putida and C. necator. To this end, this study described seamless cloning and expression methods utilizing SureVector (SV) system for generating pSV-Ortho-PHA (pSVOP) expression platform in bioengineered P. putida and C. necator. Genetic parts specifically Trc promoter, pBBR1 origin of replication, anchoring proteins and signal sequences were utilized for the transformation of pSVOP-based plasmid in electrocompetent cells and orthogonal expression of PETase in both P. putida and C. necator. Validation steps in confirming functional expression of PETase activity in corresponding PETase-expressing strains were also described to demonstrate seamless and detailed methods in establishing bioengineered P. putida and C. necator as whole-cell biocatalysts tailored for plastic bio-upcycling.•Seamless plasmid construction for orthogonal expression in PHA-producing bacteria.•Step-by-step guide for high-efficiency generation of electrotransformants of P. putida and C. necator.•Adaptable methods for rapid strain development (Design, Build, Test and Learn) for whole-cell biocatalysis.

4.
Mol Biol Rep ; 50(6): 5283-5294, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37148413

RESUMO

BACKGROUND: Chalcone isomerase (CHI; EC 5.5.1.6) is one of the key enzymes in the flavonoid biosynthetic pathway that is responsible for the intramolecular cyclization of chalcones into specific 2S-flavanones. METHODS AND RESULTS: In this study, the open reading frame (ORF) of CHI was successfully isolated from the cDNA of Polygonum minus at 711-bp long, encoding for 236 amino acid residues, with a predicted molecular weight of 25.4 kDa. Multiple sequence alignment and phylogenetic analysis revealed that the conserved residues (Thr50, Tyr108, Asn115, and Ser192) in the cleft of CHI enzyme group active site are present in PmCHI protein sequence and classified as type I. PmCHI comprises more hydrophobic residues without a signal peptide and transmembrane helices. The three-dimensional (3D) structure of PmCHI predicted through homology modeling was validated by Ramachandran plot and Verify3D, with values within the acceptable range of a good model. PmCHI was cloned into pET-28b(+) plasmid, expressed in Escherichia coli BL21(DE3) at 16 °C and partially purified. CONCLUSION: These findings contribute to a deeper understanding of the PmCHI protein and its potential for further characterization of its functional properties in the flavonoid biosynthetic pathway.


Assuntos
Polygonum , Polygonum/genética , Polygonum/metabolismo , Filogenia , Clonagem Molecular , Flavonoides/metabolismo
5.
J Biosci Bioeng ; 135(4): 259-265, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36803862

RESUMO

Saccharomyces cerevisiae has a long-standing history of biotechnological applications even before the dawn of modern biotechnology. The field is undergoing accelerated advancement with the recent systems and synthetic biology approaches. In this review, we highlight the recent findings in the field with a focus on omics studies of S. cerevisiae to investigate its stress tolerance in different industries. The latest advancements in S. cerevisiae systems and synthetic biology approaches for the development of genome-scale metabolic models (GEMs) and molecular tools such as multiplex Cas9, Cas12a, Cpf1, and Csy4 genome editing tools, modular expression cassette with optimal transcription factors, promoters, and terminator libraries as well as metabolic engineering. Omics data analysis is key to the identification of exploitable native genes/proteins/pathways in S. cerevisiae with the optimization of heterologous pathway implementation and fermentation conditions. Through systems and synthetic biology, various heterologous compound productions that require non-native biosynthetic pathways in a cell factory have been established via different strategies of metabolic engineering integrated with machine learning.


Assuntos
Saccharomyces cerevisiae , Biologia Sintética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Engenharia Metabólica , Edição de Genes , Vias Biossintéticas
6.
J Fungi (Basel) ; 8(8)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36012782

RESUMO

Ganoderma boninense is the major causal agent of basal stem rot (BSR) disease in oil palm, causing the progressive rot of the basal part of the stem. Despite its prominence, the key pathogenicity determinants for the aggressive nature of hemibiotrophic infection remain unknown. In this study, genome sequencing and the annotation of G. boninense T10 were carried out using the Illumina sequencing platform, and comparative genome analysis was performed with previously reported G. boninense strains (NJ3 and G3). The pan-secretome of G. boninense was constructed and comprised 937 core orthogroups, 243 accessory orthogroups, and 84 strain-specific orthogroups. In total, 320 core orthogroups were enriched with candidate effector proteins (CEPs) that could be classified as carbohydrate-active enzymes, hydrolases, and non-catalytic proteins. Differential expression analysis revealed an upregulation of five CEP genes that was linked to the suppression of PTI signaling cascade, while the downregulation of four CEP genes was linked to the inhibition of PTI by preventing host defense elicitation. Genome architecture analysis revealed the one-speed architecture of the G. boninense genome and the lack of preferential association of CEP genes to transposable elements. The findings obtained from this study aid in the characterization of pathogenicity determinants and molecular biomarkers of BSR disease.

7.
Iran J Biotechnol ; 20(1): e3020, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35891960

RESUMO

Context: Cymbidium mosaic virus (CymMV) is one of the most devastating viruses causing losses in the orchid industry, affecting economies worth millions of US dollars. CymMV significantly affects the orchid population and could be controlled through an integrated management strategy consisting of virus detection, good sanitation care of gardeners and their tools, and maintaining virus-free explants. Evidence acquisition: This review was written based on research publications relevant to the CymMV infection in orchids. The literature cited were obtained from online literature databases such as web of Science, Scopus, and Google Scholar. The searched term used was "Cymbidium mosaic virus". Related publications to the initial search were also examined. Results & Conclusions: This review describes the threat of CymMV to the orchid population by examining its history, genome organization, symptoms on individual orchids, detection, and management. Current research has been focusing on the prospect of transgenic orchids with viral resistance. This review also highlights the potential role of the symbiotic relationship between orchids and arbuscular mycorrhiza fungi that could be useful to improve the protection of orchids against virus infection. Overall, this review provides information on how CymMV infection impacts the orchid population.

8.
Plant Physiol Biochem ; 183: 23-35, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35537348

RESUMO

Neprosin was first discovered in the insectivorous tropical pitcher plants of Nepenthes species as a novel protease with prolyl endopeptidase (PEP) activity. Neprosin has two uncharacterized domains of neprosin activation peptide and neprosin. A previous study has shown neprosin activity in hydrolyzing proline-rich gliadin, a gluten component that triggers celiac disease. In this study, we performed in silico structure-function analysis to investigate the catalytic mechanism of neprosin. Neprosin sequences lack the catalytic triad and motifs of PEP family S9. Protein structures of neprosins from Nepenthes × ventrata (NvNpr) and N. rafflesiana (NrNpr1) were generated by ab initio methods and comparatively assessed to obtain high-quality models. Structural alignment of models to experimental structures in the Protein Data Bank (PDB) found a high structural similarity to glutamic peptidases. Further investigations reveal other resemblances to the glutamic peptidases with low optimum pH that activates the enzyme via autoproteolysis for maturation. Two highly conserved glutamic acid residues, which are stable according to the molecular dynamics simulation, can be found at the active site of the substrate cleft. Protein docking demonstrated that mature neprosins bind well with potent antigen αI-gliadin at the putative active site. Taken together, neprosins represent a new glutamic peptidase family, with a putative catalytic dyad of two glutamic acids. This study illustrates a hypothetical enzymatic mechanism of the neprosin family and demonstrates the useful application of an accurate ab initio protein structure prediction in the structure-function study of a novel protein family.


Assuntos
Gliadina , Peptídeo Hidrolases , Domínio Catalítico , Gliadina/metabolismo , Peptídeo Hidrolases/metabolismo , Peptídeos/química , Proteólise
9.
Biology (Basel) ; 10(7)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209952

RESUMO

Begomovirus has become a potential threat to the agriculture sector. It causes significant losses to several economically important crops. Given this considerable loss, the development of tools to study viral genomes and function is needed. Infectious clones approaches and applications have allowed the direct exploitation of virus genomes. Infectious clones of DNA viruses are the critical instrument for functional characterization of the notable and newly discovered virus. Understanding of structure and composition of viruses has contributed to the evolution of molecular plant pathology. Therefore, this review provides extensive guidelines on the strategy to construct infectious clones of Begomovirus. Also, this technique's impacts and benefits in controlling and understanding the Begomovirus infection will be discussed.

10.
Molecules ; 25(24)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339375

RESUMO

In solving the issue of basal stem rot diseases caused by Ganoderma, an investigation of Scytalidium parasiticum as a biological control agent that suppresses Ganoderma infection has gained our interest, as it is more environmentally friendly. Recently, the fungal co-cultivation has emerged as a promising method to discover novel antimicrobial metabolites. In this study, an established technique of co-culturing Scytalidium parasiticum and Ganoderma boninense was applied to produce and induce metabolites that have antifungal activity against G. boninense. The crude extract from the co-culture media was applied to a High Performance Liquid Chromatography (HPLC) preparative column to isolate the bioactive compounds, which were tested against G. boninense. The fractions that showed inhibition against G. boninense were sent for a Liquid Chromatography-Time of Flight-Mass Spectrometry (LC-TOF-MS) analysis to further identify the compounds that were responsible for the microbicidal activity. Interestingly, we found that eudistomin I, naringenin 7-O-beta-D-glucoside and penipanoid A, which were present in different abundances in all the active fractions, except in the control, could be the antimicrobial metabolites. In addition, the abundance of fatty acids, such as oleic acid and stearamide in the active fraction, also enhanced the antimicrobial activity. This comprehensive metabolomics study could be used as the basis for isolating biocontrol compounds to be applied in oil palm fields to combat a Ganoderma infection.


Assuntos
Alcaloides/química , Antifúngicos/química , Ascomicetos/química , Ácidos Graxos/química , Flavonoides/química , Ganoderma/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antifúngicos/análise , Antifúngicos/farmacologia , Ascomicetos/metabolismo , Técnicas de Cultura Celular por Lotes , Cromatografia Líquida de Alta Pressão , Análise Discriminante , Ácidos Graxos/isolamento & purificação , Ácidos Graxos/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Ganoderma/efeitos dos fármacos , Ganoderma/metabolismo , Análise dos Mínimos Quadrados , Análise de Componente Principal , Espectrometria de Massas por Ionização por Electrospray
11.
J Oral Pathol Med ; 49(9): 835-841, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32170981

RESUMO

Oral squamous cell carcinoma is associated with many known risk factors including tobacco smoking, chronic alcoholism, poor oral hygiene, unhealthy dietary habits and microbial infection. Previous studies have highlighted Candida albicans host tissue infection as a risk factor in the initiation and progression of oral cancer. C albicans invasion induces several cancerous hallmarks, such as activation of proto-oncogenes, induction of DNA damage and overexpression of inflammatory signalling pathways. However, the molecular mechanisms behind these responses remain unclear. A recently discovered fungal toxin peptide, candidalysin, has been reported as an essential molecule in epithelial damage and host recognition of C albicans infection. Candidalysin has a clear role in inflammasome activation and induction of cell damage. Several inflammatory molecules such as IL-6, IL-17, NLRP3 and GM-CSF have been linked to carcinogenesis. Candidalysin is encoded by the ECE1 gene, which has been linked to virulence factors of C albicans such as adhesion, biofilm formation and filamentation properties. This review discusses the recent epidemiological burden of oral cancer and highlights the significance of the ECE1 gene and the ECE1 protein breakdown product, candidalysin in oral malignancy. The immunological and molecular mechanisms behind oral malignancy induced by inflammation and the role of the toxic fungal peptide candidalysin in oral carcinogenesis are explored. With increasing evidence associating C albicans with oral carcinoma, identifying the possible fungal pathogenicity factors including the role of candidalysin can assist in efforts to understand the link between C albicans infection and carcinogenesis, and pave the way for research into therapeutic potentials.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Candida albicans/genética , Carcinogênese/genética , Enzimas Conversoras de Endotelina , Proteínas Fúngicas , Humanos , Neoplasias Bucais/genética
12.
Front Bioeng Biotechnol ; 8: 608918, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33409270

RESUMO

Increasing demands for the supply of biopharmaceuticals have propelled the advancement of metabolic engineering and synthetic biology strategies for biomanufacturing of bioactive natural products. Using metabolically engineered microbes as the bioproduction hosts, a variety of natural products including terpenes, flavonoids, alkaloids, and cannabinoids have been synthesized through the construction and expression of known and newly found biosynthetic genes primarily from model and non-model plants. The employment of omics technology and machine learning (ML) platforms as high throughput analytical tools has been increasingly leveraged in promoting data-guided optimization of targeted biosynthetic pathways and enhancement of the microbial production capacity, thereby representing a critical debottlenecking approach in improving and streamlining natural products biomanufacturing. To this end, this mini review summarizes recent efforts that utilize omics platforms and ML tools in strain optimization and prototyping and discusses the beneficial uses of omics-enabled discovery of plant biosynthetic genes in the production of complex plant-based natural products by bioengineered microbes.

13.
PeerJ ; 7: e8065, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31879570

RESUMO

BACKGROUND: G. boninense is a hemibiotrophic fungus that infects oil palms (Elaeis guineensis Jacq.) causing basal stem rot (BSR) disease and consequent massive economic losses to the oil palm industry. The pathogenicity of this white-rot fungus has been associated with cell wall degrading enzymes (CWDEs) released during saprophytic and necrotrophic stage of infection of the oil palm host. However, there is a lack of information available on the essentiality of CWDEs in wood-decaying process and pathogenesis of this oil palm pathogen especially at molecular and genome levels. METHODS: In this study, comparative genome analysis was carried out using the G. boninense NJ3 genome to identify and characterize carbohydrate-active enzyme (CAZymes) including CWDE in the fungal genome. Augustus pipeline was employed for gene identification in G. boninense NJ3 and the produced protein sequences were analyzed via dbCAN pipeline and PhiBase 4.5 database annotation for CAZymes and plant-host interaction (PHI) gene analysis, respectively. Comparison of CAZymes from G. boninense NJ3 was made against G. lucidum, a well-studied model Ganoderma sp. and five selected pathogenic fungi for CAZymes characterization. Functional annotation of PHI genes was carried out using Web Gene Ontology Annotation Plot (WEGO) and was used for selecting candidate PHI genes related to cell wall degradation of G. boninense NJ3. RESULTS: G. boninense was enriched with CAZymes and CWDEs in a similar fashion to G. lucidum that corroborate with the lignocellulolytic abilities of both closely-related fungal strains. The role of polysaccharide and cell wall degrading enzymes in the hemibiotrophic mode of infection of G. boninense was investigated by analyzing the fungal CAZymes with necrotrophic Armillaria solidipes, A. mellea, biotrophic Ustilago maydis, Melampsora larici-populina and hemibiotrophic Moniliophthora perniciosa. Profiles of the selected pathogenic fungi demonstrated that necrotizing pathogens including G. boninense NJ3 exhibited an extensive set of CAZymes as compared to the more CAZymes-limited biotrophic pathogens. Following PHI analysis, several candidate genes including polygalacturonase, endo ß-1,3-xylanase, ß-glucanase and laccase were identified as potential CWDEs that contribute to the plant host interaction and pathogenesis. DISCUSSION: This study employed bioinformatics tools for providing a greater understanding of the biological mechanisms underlying the production of CAZymes in G. boninense NJ3. Identification and profiling of the fungal polysaccharide- and lignocellulosic-degrading enzymes would further facilitate in elucidating the infection mechanisms through the production of CWDEs by G. boninense. Identification of CAZymes and CWDE-related PHI genes in G. boninense would serve as the basis for functional studies of genes associated with the fungal virulence and pathogenicity using systems biology and genetic engineering approaches.

14.
Mol Biol Rep ; 46(6): 6647-6659, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31535322

RESUMO

Flavonoids are polyphenols that are important organic chemicals in plants. The health benefits of flavonoids that result in high commercial values make them attractive targets for large-scale production through bioengineering. Strategies such as engineering a flavonoid biosynthetic pathway in microbial hosts provide an alternative way to produce these beneficial compounds. Escherichia coli, Saccharomyces cerevisiae and Streptomyces sp. are among the expression systems used to produce recombinant products, as well as for the production of flavonoid compounds through various bioengineering approaches including clustered regularly interspaced short palindromic repeats (CRISPR)-based genome engineering and genetically encoded biosensors to detect flavonoid biosynthesis. In this study, we review the recent advances in engineering model microbial hosts as being the factory to produce targeted flavonoid compounds.


Assuntos
Técnicas Bacteriológicas/métodos , Flavonoides/biossíntese , Engenharia Metabólica/métodos , Vias Biossintéticas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Flavonoides/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Streptomyces/genética , Streptomyces/crescimento & desenvolvimento
15.
Adv Exp Med Biol ; 1102: 81-95, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30382570

RESUMO

In the modern era of next-generation genomics and Fourth Industrial Revolution, there is a growing demand for translational research that brings about not only impactful research but also potential commercialisation of R- and D-based products. Advancement of metabolic engineering and synthetic biology has put forward a viable and innovative biotechnological platform for bioproduct development especially using microbial chassis. In this chapter, readers will be introduced on the concepts of metabolic engineering, synthetic biology and microbial chassis and the applications of these biological engineering (BioE) components in the advancement of industrial and agricultural biotechnology. Main strategies in employing BioE platform are discussed especially for waste bioconversion and value-added product development. More importantly, this chapter will also discuss current endeavours in integrating systems and synthetic biology for microbial production of natural products by introducing flavonoid biosynthesis genes of Polygonum minus, a medicinally important tropical plant in engineered yeast.


Assuntos
Engenharia Metabólica , Biologia Sintética , Biotecnologia , Genômica , Pesquisa Translacional Biomédica
16.
Molecules ; 23(6)2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29882808

RESUMO

Polygonum minus (syn. Persicaria minor) is a herbal plant that is well known for producing sesquiterpenes, which contribute to its flavour and fragrance. This study describes the cloning and functional characterisation of PmSTPS1 and PmSTPS2, two sesquiterpene synthase genes that were identified from P. minus transcriptome data mining. The full-length sequences of the PmSTPS1 and PmSTPS2 genes were expressed in the E. coli pQE-2 expression vector. The sizes of PmSTPS1 and PmSTPS2 were 1098 bp and 1967 bp, respectively, with open reading frames (ORF) of 1047 and 1695 bp and encoding polypeptides of 348 and 564 amino acids, respectively. The proteins consist of three conserved motifs, namely, Asp-rich substrate binding (DDxxD), metal binding residues (NSE/DTE), and cytoplasmic ER retention (RxR), as well as the terpene synthase family N-terminal domain and C-terminal metal-binding domain. From the in vitro enzyme assays, using the farnesyl pyrophosphate (FPP) substrate, the PmSTPS1 enzyme produced multiple acyclic sesquiterpenes of ß-farnesene, α-farnesene, and farnesol, while the PmSTPS2 enzyme produced an additional nerolidol as a final product. The results confirmed the roles of PmSTPS1 and PmSTPS2 in the biosynthesis pathway of P. minus, to produce aromatic sesquiterpenes.


Assuntos
Ligases/metabolismo , Polygonum/enzimologia , Sesquiterpenos/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Genes de Plantas , Ligases/química , Ligases/genética , Malásia , Fases de Leitura Aberta , Filogenia , Polygonum/genética , Homologia de Sequência de Aminoácidos
17.
Enzyme Microb Technol ; 81: 1-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26453466

RESUMO

ALA (5-aminolevulinic acid) is an important intermediate in the synthesis of tetrapyrroles and the use of ALA has been gradually increasing in many fields, including medicine and agriculture. In this study, improved biological production of ALA in Corynebacterium glutamicum was achieved by overexpressing glutamate-initiated C5 pathway. For this purpose, copies of the glutamyl t-RNA reductase HemA from several bacteria were mutated by site-directed mutagenesis of which a HemA version from Salmonella typhimurium exhibited the highest ALA production. Cultivation of the HemA-expressing strain produced approximately 204 mg/L of ALA, while co-expression with HemL (glutamate-1-semialdehyde aminotransferase) increased ALA concentration to 457 mg/L, representing 11.6- and 25.9-fold increases over the control strain (17 mg/L of ALA). Further effects of metabolic perturbation were investigated, leading to penicillin addition that further improves ALA production to 584 mg/L. In an optimized flask fermentation, engineered C. glutamicum strains expressing the HemA and hemAL operon produced up to 1.1 and 2.2g/L ALA, respectively, under glutamate-producing conditions. The final yields represent 10.7- and 22.0-fold increases over the control strain (0.1g/L of ALA). From these findings, ALA biosynthesis from glucose was successfully demonstrated and this study is the first to report ALA overproduction in C. glutamicum via metabolic engineering.


Assuntos
Ácido Aminolevulínico/metabolismo , Corynebacterium glutamicum/metabolismo , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vias Biossintéticas , Corynebacterium glutamicum/genética , Fermentação , Genes Bacterianos , Ácido Glutâmico/metabolismo , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Engenharia Metabólica , Óperon , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
18.
Biotechnol Bioeng ; 110(1): 343-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22886471

RESUMO

Triacylglycerol (TAG) is a microbial oil feedstock for biodiesel production that uses an inexpensive substrate, such as glycerol. Here, we demonstrated the overproduction of TAG from glycerol in engineered Saccharomyces cerevisiae via the glycerol-3-phosphate (G3P) pathway by overexpressing the major TAG synthesis. The G3P accumulation was increased 2.4-fold with the increased glycerol utilization gained by the overexpression of glycerol kinase (GUT1). By overexpressing diacylglycerol acyltransferase (DGA1) and phospholipid diacylglycerol acyltransferase (LRO1), the engineered YPH499 (pGutDgaLro1) strain produced 23.0 mg/L lipids, whereas the YPH499 (pESC-TRP) strain produced 6.2 mg/L total lipids and showed a lipid content that was increased 1.4-fold compared with 3.6% for the wild-type strain after 96 h of cultivation. After 96 h of cultivation using glycerol, the overall content of TAG in the engineered strain, YPH499 (pGutDgaLro1), yielded 8.2% TAG, representing a 2.3-fold improvement, compared with 3.6% for the wild-type strain. The results should allow a reduction of costs and a more sustainable production of biodiesel.


Assuntos
Biocombustíveis/microbiologia , Glicerol/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Triglicerídeos/metabolismo , Bioengenharia , Processos de Crescimento Celular/fisiologia , Glicerol/análise , Glicerofosfatos/análise , Glicerofosfatos/metabolismo , Redes e Vias Metabólicas , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Triglicerídeos/análise
19.
Enzyme Microb Technol ; 51(4): 237-43, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22883559

RESUMO

During the industrial production of ethanol using yeast, the cells are exposed to stresses that affect their growth and productivity; therefore, stress-tolerant yeast strains are highly desirable. To increase ethanol production from glycerol, a greater tolerance to osmotic and ethanol stress was engineered in yeast strains that were impaired in endogenous glycerol production by the overexpression of both SPT3 and SPT15, components of the SAGA (Spt-Ada-Gcn5-acetyltransferase) complex. The engineered strain YPH499fps1Δgpd2Δ (pGcyaDak, pGupSpt3.15Cas) formed significantly more biomass compared to the strain YPH499fps1Δgpd2Δ (pGcyaDak, pGupCas), and both engineered strains displayed increased biomass when compared to the control YPH499 fps1Δgpd2Δ (pESC-TRP) strain. The trehalose accumulation and ergosterol content of these strains were 2.3-fold and 1.6-fold higher, respectively, than the parent strains, suggesting that levels of cellular membrane components were correlated with the enhanced stress tolerance of the engineered strains. Consequently, the ethanol production of the engineered strain YPH499fps1Δgpd2Δ (pGcyaDak, pGupSpt3.15Cas) was 1.8-fold more than that of strain YPH499fps1Δgpd2Δ (pGcyaDak, pGupCas), with about 8.1g/L ethanol produced. In conclusion, we successfully established that the co-expression of SPT3 and SPT15 that improved the fermentation performance of the engineered yeast strains which produced higher ethanol yields than stress-sensitive yeast strains.


Assuntos
Biotecnologia/métodos , Etanol/metabolismo , Glicerol/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia , Proteína de Ligação a TATA-Box/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Cima , Fermentação , Regulação Fúngica da Expressão Gênica , Engenharia Genética/métodos , Resposta ao Choque Térmico/fisiologia , Pressão Osmótica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteína de Ligação a TATA-Box/genética , Fatores de Transcrição/genética
20.
Biotechnol Bioeng ; 109(9): 2349-56, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22511326

RESUMO

Surfactin is a biological surfactant with numerous potential applications. In this study, Bacillus subtilis was engineered to improve surfactin production by the activation of two competence-stimulating pheromones, ComX and competence and sporulation factor (CSF) to stimulate the transcription of srfA operon. Both signaling factors, encoded by comX and phrC, were successfully overexpressed and subsequently increased surfactin production. Surfactin produced by engineered strains showed functional groups similar to the commercially available surfactin analyzed via Fourier transform infrared spectroscopy (FTIR). Surfactin production in the B. subtilis (pHT43-comXphrC) strain was 6.4-fold greater than in the wild strain, with approximately 135.1 mg/L surfactin produced after 48 h cultivation. To reduce the production costs of surfactin, synthetic wastewater was used, from which the B. subtilis (pHT43-comXphrC) strain produced approximately 140.2 mg/L surfactin. The results obtained demonstrated the production of surfactin from synthetic wastewater, which is beneficial in lowering the overall production costs.


Assuntos
Bacillus subtilis/metabolismo , Proteínas de Bactérias/biossíntese , Lipopeptídeos/biossíntese , Peptídeos Cíclicos/biossíntese , Proteínas Repressoras/biossíntese , Água/metabolismo , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Engenharia Genética , Lipopeptídeos/economia , Lipopeptídeos/metabolismo , Modelos Químicos , Peptídeos Cíclicos/economia , Peptídeos Cíclicos/metabolismo , Plasmídeos/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Esgotos
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