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1.
Res Microbiol ; : 104188, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38286394

RESUMO

The complete genome of Corynebacterium glutamicum contain a gene encoding murein endopeptidase MepA which maintain cell wall homeostasis by regulating peptidoglycan biosynthesis. In this study, we investigate the physiological function, localization and regulator of MepA. The result shows that mepA overexpression lead to peptidoglycan degradation and the defects in cell division. MepA-mCherry was shown to localizes exclusively at the cell cell septum. In addition, mepA overexpression increased cell permeability and reduced the resistance of cells to isoniazid, an antibiotic used to treat Mycobacterium tuberculosis infection. Furthermore, transcription analysis showed that mepA affected cell division and membrane transport pathways, and was coordinately regulated by the two-component systems MtrAB and MprAB(CgtS/R2).

2.
Chembiochem ; 24(24): e202300587, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-37783667

RESUMO

Most natural formate dehydrogenases (FDHs) exhibit NAD+ specificity, making it imperative to explore the engineering of FDH cofactor specificity for NADPH regeneration systems. The endogenous FDH of Komagataella phaffii (K. phaffii), termed KphFDH, is a typical NAD+ -specific FDH. However, investigations into engineering the cofactor specificity of KphFDH have yet to be conducted. To develop an NADP+ -specific variant of KphFDH, we selected D195, Y196, and Q197 as mutation sites and generated twenty site-directed variants. Through kinetic characterization, KphFDH/V19 (D195Q/Y196R/Q197H) was identified as the variant with the highest specificity towards NADP+ , with a ratio of catalytic efficiency (kcat /KM )NADP+ /(kcat /KM )NAD+ of 129.226. Studies of enzymatic properties revealed that the optimal temperature and pH for the reduction reaction of NADP+ catalyzed by KphFDH/V19 were 45 °C and 7.5, respectively. The molecular dynamics (MD) simulation was performed to elucidate the mechanism of high catalytic activity of KphFDH/V19 towards NADP+ . Finally, KphFDH/V19 was applied to an in vitro NADPH regeneration system with Meso-diaminopimelate dehydrogenase from Symbiobacterium thermophilum (StDAPDH/H227V). This study successfully created a KphFDH variant with high NADP+ specificity and demonstrated its practical applicability in an in vitro NADPH regeneration system.


Assuntos
NAD , Saccharomycetales , NADP/metabolismo , NAD/metabolismo , Formiato Desidrogenases/química , Saccharomycetales/metabolismo , Cinética
3.
Int Immunopharmacol ; 124(Pt B): 111032, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832239

RESUMO

Interleukin-5 (IL-5) is a homodimeric cytokine that is a crucial regulator of the proliferation, activation, and maturation of eosinophils. Anti-IL-5 monoclonal antibodies, which block the binding of IL-5 to the IL-5 receptor subunit alpha (IL-5Rα), have been successfully used to treat eosinophilic (EOS) asthma. The currently marketed monoclonal antibody drugs require repeated injections for administration, which seriously affect patient compliance and high systemic exposure for injectable drug delivery. Here we successfully screened and developed the Fab (fragment of antigen binding), which is 1/3rd the molecular weight of IgG, favoring inhalation-mediated delivery to the lungs, making it more effective for asthma treatment. The 20A12-Fab-H12L3 can bind to IL-5 with a binding constant of 1.236E-09 M while significantly inhibiting the IL-5/IL-5Rα complex formation. We found that the light chain amino acids (S46 and F71) significantly affected the antibody expression during humanization. The 20A12-Fab-H12L3 significantly inhibited the proliferation of TF-1 cells and blocked the IL-5 binding to the IL-5Rα-overexpressing human embryonic kidney (HEK)-293 cells in vitro. Therefore, based on the mutant IL-5 binding with Fab, we explained why antibodies blocked IL-5 binding to IL-5Rα. Thus, this study provided a candidate pharmaceutical antibody for inhalation drug delivery.


Assuntos
Asma , Interleucina-5 , Humanos , Interleucina-5/metabolismo , Fragmentos Fab das Imunoglobulinas/metabolismo , Células HEK293 , Eosinófilos , Asma/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico
4.
Microb Cell Fact ; 22(1): 182, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715258

RESUMO

In the post-genomic era, the demand for faster and more efficient protein production has increased, both in public laboratories and industry. In addition, with the expansion of protein sequences in databases, the range of possible enzymes of interest for a given application is also increasing. Faced with peer competition, budgetary, and time constraints, companies and laboratories must find ways to develop a robust manufacturing process for recombinant protein production. In this review, we explore high-throughput technologies for recombinant protein expression and present a holistic high-throughput process development strategy that spans from genes to proteins. We discuss the challenges that come with this task, the limitations of previous studies, and future research directions.


Assuntos
Genômica , Laboratórios , Clonagem Molecular , Sequência de Aminoácidos , Proteínas Recombinantes/genética
5.
ACS Synth Biol ; 12(9): 2725-2739, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37607052

RESUMO

Lycopene biosynthesis is frequently hampered by downstream processing hugely due to its inability to be secreted out from the producing chassis. Engineering cell factories can resolve this issue by secreting this hydrophobic compound. A highly permeable E. coli strain was developed for a better release rate of lycopene. Specifically, the heterologous mevalonate pathway and crtEBI genes from Corynebacterium glutamicum were overexpressed in Escherichia coli BL21 (DE3) for lycopene synthesis. To ensure in situ lycopene production, murein lipoprotein, lipoprotein NlpI, inner membrane permease protein, and membrane-anchored protein in TolA-TolQ-TolR were deleted for improved membrane permeability. The final strain, LYC-8, produced 438.44 ± 8.11 and 136.94 ± 1.94 mg/L of extracellular and intracellular lycopene in fed-batch fermentation. Both proteomics and lipidomics analyses of secreted outer membrane vesicles were perfect indicators of hypervesiculation. Changes in the ratio of saturated fatty acids, unsaturated fatty acids, and cyclopropane fatty acids coupled with the branching and acyl chain lengths altered the membrane fatty acid composition. This ensured membrane fluidity and permeability for in situ lycopene release. The combinatorial deletion of these genes altered the cellular morphology. The structural and morphological changes in cell shape, size, and length were associated with changes in the mechanical strength of the cell envelope. The enhanced lycopene production and secretion mediated by improved membrane permeability established a cell lysis-free system for an efficient releasing rate and downstream processing, demonstrating the importance of vesicle-associated membrane permeability in efficient lycopene production.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Licopeno , Transporte Biológico , Morte Celular , Membrana Celular , Lipoproteínas , Proteínas de Escherichia coli/genética
6.
Sheng Wu Gong Cheng Xue Bao ; 39(8): 3364-3378, 2023 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-37622366

RESUMO

With various diseases ravaging internationally, the demands for recombinant adenoviral vector (Adv) vaccines have increased dramatically. To meet the demand for Adv vaccine, development of a new cell culture process is an effective strategy. Applying hyperosmotic stress in cells before virus infection could increase the yield of Adv in batch culture mode. Emerging perfusion culture can significantly increase the yield of Adv as well. Therefore, combining the hyperosmotic stress process with perfusion culture is expected to improve the yield of Adv at high cell density. In this study, a shake flask combined with a semi-perfusion culture was used as a scaled-down model for bioreactor perfusion culture. Media with osmotic pressure ranging from 300 to 405 mOsm were used to study the effect of hyperosmotic stress on cell growth and Adv production. The results showed that using a perfusion culture process with a hyperosmotic pressure medium (370 mOsm) during the cell growth phase and an isosmotic pressure medium (300 mOsm) during the virus production phase effectively increased the yield of Adv. This might be due to the increased expression of HSP70 protein during the late phases of virus replication. The Adv titer in a bioreactor with such a process reached 3.2×1010 IFU/mL, three times higher than that of the traditional perfusion culture process. More importantly, this is the first time that a strategy of combining the hyperosmotic stress process with perfusion culture is applied to the production of Adv in HEK 293 cells. It also reveals the reason why the hyperosmotic stress process increased the yield of Adv, which may facilitate the process optimization of for producing other Adv in HEK 293 cells.


Assuntos
Técnicas de Cultura Celular por Lotes , Vetores Genéticos , Humanos , Células HEK293 , Vetores Genéticos/genética , Reatores Biológicos , Perfusão
7.
ACS Synth Biol ; 12(8): 2226-2235, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37463503

RESUMO

Saccharomyces cerevisiae has been extensively used as a convenient synthetic biology chassis to reconstitute fungal polyketide biosynthetic pathways. Despite progress in refactoring these pathways for expression and optimization of the yeast production host by metabolic engineering, product yields often remain unsatisfactory. Such problems are especially acute when synthetic biological production is used for bioprospecting via genome mining or when chimeric fungal polyketide synthases (PKSs) are employed to produce novel bioactive compounds. In this work, we demonstrate that empirically balancing the expression levels of the two collaborating PKS subunits that afford benzenediol lactone (BDL)-type fungal polyketides is a facile strategy to improve the product yields. This is accomplished by systematically and independently altering the copy numbers of the two plasmids that express these PKS subunits. We applied this plasmid copy number engineering strategy to two orphan PKSs from genome mining where the yields of the presumed BDL products in S. cerevisiae were far too low for product isolation. This optimization resulted in product yield improvements of up to 10-fold, allowing for the successful isolation and structure elucidation of new BDL analogues. Heterocombinations of these PKS subunits from genome mining with those from previously identified BDL pathways led to the combinatorial biosynthesis of several additional novel BDL-type polyketides.


Assuntos
Policetídeos , Policetídeos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Variações do Número de Cópias de DNA , Policetídeo Sintases/metabolismo , Lactonas/metabolismo , Plasmídeos/genética
8.
Biotechnol Bioeng ; 120(10): 3039-3056, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37309999

RESUMO

ß-elemene is one of the most commonly used antineoplastic drugs in cancer treatment. As a plant-derived natural chemical, biologically engineering microorganisms to produce germacrene A to be converted to ß-elemene harbors great expectations since chemical synthesis and plant isolation methods come with their production deficiencies. In this study, we report the design of an Escherichia coli cell factory for the de novo production of germacrene A to be converted to ß-elemene from a simple carbon source. A series of systematic approaches of engineering the isoprenoid and central carbon pathways, translational and protein engineering of the sesquiterpene synthase, and exporter engineering yielded high-efficient ß-elemene production. Specifically, deleting competing pathways in the central carbon pathway ensured the availability of acetyl-coA, pyruvate, and glyceraldehyde-3-phosphate for the isoprenoid pathways. Adopting lycopene color as a high throughput screening method, an optimized NSY305N was obtained via error-prone polymerase chain reaction mutagenesis. Further overexpression of key pathway enzymes, exporter genes, and translational engineering produced 1161.09 mg/L of ß-elemene in a shake flask. Finally, we detected the highest reported titer of 3.52 g/L of ß-elemene and 2.13 g/L germacrene A produced by an E. coli cell factory in a 4-L fed-batch fermentation. The systematic engineering reported here generally applies to microbial production of a broader range of chemicals. This illustrates that rewiring E. coli central metabolism is viable for producing acetyl-coA-derived and pyruvate-derived molecules cost-effectively.


Assuntos
Escherichia coli , Sesquiterpenos , Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Metabólica/métodos , Acetilcoenzima A/metabolismo , Sesquiterpenos/metabolismo , Carbono/metabolismo
9.
ACS Synth Biol ; 12(7): 2157-2167, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37350137

RESUMO

In synthetic biology, the precise control of gene expression is challenging due to the limited orthogonality of expression elements. Here, to address this issue and improve the reusability of genetic elements, we developed a bicistronic expression cassette in Corynebacterium glutamicum based on a leaderless promoter lacking a 5'UTR. The created leaderless bicistronic design (BCD) significantly improved the orthogonality of expression elements across different genes of interest. We also explored the importance of the fore-cistron and SD motif in maintaining the strength of leaderless BCDs. Additionally, we established a library containing 55,901 fore-cistrons and demonstrated that the regulatory range of gene expression in leaderless BCDs can be broader by modifying the fore-cistron sequence. This study provides a novel synthetic biology tool based on leaderless BCD for fine-tuning gene expression in C. glutamicum using fore-cistrons. Moreover, the strategy developed here can also be applied to improve the performance of other leaderless promoters in other bacteria.


Assuntos
Corynebacterium glutamicum , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Regiões Promotoras Genéticas/genética , Biblioteca Gênica , Expressão Gênica , Regulação Bacteriana da Expressão Gênica/genética
10.
ACS Synth Biol ; 12(6): 1599-1607, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37172280

RESUMO

Polyketides are a class of natural products with many applications but are mainly appealing as pharmaceuticals. Heterologous production of polyketides in the yeast Saccharomyces cerevisiae has been widely explored because of the many merits of this model eukaryotic microorganism. Although acetyl-CoA and malonyl-CoA, the precursors for polyketide synthesis, are distributed in several yeast subcellular organelles, only cytosolic synthesis of polyketides has been pursued in previous studies. In this study, we investigate polyketide synthesis by directly using acetyl-CoA in the peroxisomes of yeast strain CEN.PK2-1D. We first demonstrate that the polyketide flaviolin can be synthesized in this organelle upon peroxisomal colocalization of native acetyl-CoA carboxylase and 1,3,6,8-tetrahydroxynaphthalene synthase (a type III polyketide synthase). Next, using the synthesis of the polyketide triacetic acid lactone as an example, we show that (1) a new peroxisome targeting sequence, pPTS1, is more effective than the previously reported ePTS1 for peroxisomal polyketide synthesis; (2) engineering peroxisome proliferation is effective to boost polyketide production; and (3) peroxisomes provide an additional acetyl-CoA reservoir and extra space to accommodate enzymes so that utilizing the peroxisomal pathway plus the cytosolic pathway produces more polyketide than the cytosolic pathway alone. This research lays the groundwork for more efficient heterologous polyketide biosynthesis using acetyl-CoA pools in subcellular organelles.


Assuntos
Policetídeos , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Acetilcoenzima A/metabolismo , Policetídeos/metabolismo , Malonil Coenzima A/metabolismo , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo
11.
J Gen Appl Microbiol ; 69(1): 34-44, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-36878578

RESUMO

Protein synthesis in Corynebacterium glutamicum is critical for applications in biotechnology and medicine. However, the use of C. glutamicum for protein production is limited by its low expression and aggregation. To overcome these limitations, a molecular chaperone plasmid system was developed in this study to improve the efficiency of recombinant protein synthesis in C. glutamicum. The effect of molecular chaperones on target protein synthesis (Single-chain variable fragment, Scfv) under three different promoter strengths was tested. In addition, the plasmid containing the molecular chaperone and target protein was verified for growth stability and plasmid stability. This expression model was further validated using two recombinant proteins, human interferon-beta (Hifn) and hirudin variant III (Rhv3). Finally, the Rhv3 protein was purified, and analysis of Rhv3 activity confirmed that the use of a molecular chaperone led to an improvement in test protein synthesis. Thus, the use of molecular chaperones is believed to will improve recombinant proteins synthesis in C. glutamicum.


Assuntos
Corynebacterium glutamicum , Humanos , Corynebacterium glutamicum/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Plasmídeos/genética , Regiões Promotoras Genéticas , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo
12.
ACS Synth Biol ; 11(10): 3305-3317, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36198145

RESUMO

Co-localizing biochemical processes is a great strategy when expressing the heterologous metabolic pathway for product biosynthesis. The RNA scaffold is a flexible and efficient synthetic compartmentalization method to co-localize the enzymes involved in the metabolic pathway by binding to the specific RNA, binding domains fused with the engineered enzymes. Herein, we designed two artificial RNA scaffold structures─0D RNA scaffolds and 2D RNA scaffolds─using the reported aptamers PP7 and BIV-Tat and the corresponding RNA-binding domains (RBDs). We verified the interaction of the RBD and RNA aptamer in vitro and in vivo. Then, we determined the efficiencies of these RNA scaffolds by co-localizing fluorescent proteins. We employed the RNA scaffolds combined with the enzyme fusion strategies to increase the metabolic flux involved in the enzymes of the mevalonate pathway for mevalonate and isoprene production. Compared with the no RNA scaffold strain, the mevalonate levels of the 0D RNA scaffolds and 2D RNA scaffolds increased by 84.1% (3.13 ± 0.03 g/L) and 76.5% (3.00 ± 0.09 g/L), respectively. We applied the 0D RNA scaffolds for increasing the isoprene production by localizing the enzymes involved in a heterologous multi-enzyme pathway. When applying the RNA scaffolds for co-localizing the enzymes mvaE and mvaS, the isoprene production reached to 609.3 ± 57.9 mg/L, increasing by 142% compared with the no RNA scaffold strain. Our results indicate that the RNA scaffold is a powerful tool for improving the efficiencies of the reaction process in the metabolic pathway.


Assuntos
Aptâmeros de Nucleotídeos , Engenharia Metabólica , Engenharia Metabólica/métodos , Ácido Mevalônico/metabolismo , Escherichia coli/metabolismo , RNA/metabolismo , Aptâmeros de Nucleotídeos/metabolismo , Redes e Vias Metabólicas/genética
13.
Appl Bionics Biomech ; 2022: 6495645, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694279

RESUMO

Pulmonary arterial hypertension (PAH) is a serious disease with reduced systemic circulation and low bioavailability associated with conventional and dosed therapy, which inhaled drugs can avoid. A mean pulmonary artery pressure (mPAP) of ≥25 mmHg (1 mmHg = 0.133 kPa) at rest or ≥30 mmHg during exercise and a pulmonary capillary pressure or left atrial pressure (PLA) of ≤15 mmHg can be diagnosed with PAH. Pulmonary hypertension is classified into primary PAH and secondary PAH according to the presence or absence of principles or risk factors. The main symptoms of pulmonary hypertension include dyspnoea, syncope, weakness, chest pain, and the presence of varying degrees of peripheral oedema. It is a highly pathogenic and life-threatening disease and can lead to delays in treatment if not diagnosed in time. In the past few years, the studies related to this progressed slowly, which brought great harm to patients with PAH. Reports showed that patients diagnosed with PAH should receive routine preventative care, such as pneumococcal and influenza vaccinations. Inhalation therapy is mainly used for the treatment of respiratory diseases and is of great interest due to the concentration of the drug in the airways and lung tissues. Therefore, the present situation of pulmonary hypertension and the characteristics of inhalation preparation were reviewed in this paper to provide some related cue for the treatment of pulmonary hypertension. In the future, it is necessary to develop more treatment methods for pulmonary hypertension.

14.
World J Microbiol Biotechnol ; 38(8): 144, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35748959

RESUMO

D-allulose is a rare low-calorie sugar that has many fundamental biological functions. D-allulose 3-epimerase from Agrobacterium tumefaciens (AT-DAEase) catalyzes the conversion of D-fructose to D-allulose. The enzyme has attracted considerable attention because of its mild catalytic properties. However, the bioconversion efficiency and reusability of AT-DAEase limit its industrial application. Magnetic metal-organic frameworks (MOFs) have uniform pore sizes and large surface areas and can facilitate mass transport and enhance the capacity for enzyme immobilization. Here, we successfully encapsulated cobalt-type AT-DAEase into the cobalt-based magnetic MOF ZIF-67@Fe3O4 using a self-assembly strategy. We confirmed the immobilization of enzyme AT-DAEase and characterized the enzymatic properties of the MOF-immobilized AT-DAEase@ZIF-67@Fe3O4. The AT-DAEase@ZIF-67@Fe3O4 nanoparticles had higher catalytic activity (65.1 U mg-1) and bioconversion ratio (38.1%) than the free AT-DAEase. The optimal conditions for maximum enzyme activity of the AT-DAEase@ZIF-67@Fe3O4 nanoparticles were 55 °C and pH 8.0, which were significantly higher than those of the free AT-DAEase (50 °C and pH 7.5). The AT-DAEase@ZIF-67@Fe3O4 nanoparticles displayed significantly improved thermal stability and excellent recycling performance, with 80% retention of enzyme activity at a temperature range of 45-70 °C and > 45% of its initial activity after eight cycles of enzyme use. The AT-DAEase@ZIF-67@Fe3O4 nanoparticles have great potential for large-scale industrial preparation of D-allulose by immobilizing cobalt-type AT-DAEase into magnetic MOF ZIF-67@Fe3O4.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Agrobacterium tumefaciens/metabolismo , Biocatálise , Cobalto , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Frutose , Concentração de Íons de Hidrogênio , Fenômenos Magnéticos , Racemases e Epimerases
15.
Biotechnol Adv ; 59: 107970, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35550915

RESUMO

The preparation of genetic libraries is an essential step to evolve microorganisms and study genotype-phenotype relationships by high-throughput screening/selection. As the large-scale synthesis of oligonucleotides becomes easy, cheap, and high-throughput, numerous novel strategies have been developed in recent years to construct high-quality oligo-mediated libraries, leveraging state-of-art molecular biology tools for genome editing and gene regulation. This review presents an overview of recent advances in creating and characterizing in vitro and in vivo genetic libraries, based on CRISPR/Cas, regulatory RNAs, and recombineering, primarily for Escherichia coli and Saccharomyces cerevisiae. These libraries' applications in high-throughput metabolic engineering, strain evolution and protein engineering are also discussed.


Assuntos
Edição de Genes , Engenharia Metabólica , Sistemas CRISPR-Cas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Genética , Oligonucleotídeos , Saccharomyces cerevisiae/genética
16.
Appl Microbiol Biotechnol ; 106(8): 2953-2967, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35435456

RESUMO

Outer membrane lipoprotein A (OmlA) is a vaccine antigen against porcine contagious pleuropneumonia (PCP), a disease severely affecting the swine industry. Here, we aimed to systematically potentiate the secretory production of OmlA in Corynebacterium glutamicum (C. glutamicum), a widely used microorganism in the food industry, by establishing a holistic development process based on our high-throughput culture platform. The expression patterns, expression element combinations, medium composition, and induction conditions were comprehensively screened or optimized in microwell plates (MWPs), followed by fermentation parameter optimization in a 4 × 1 L parallel fermentation system (CUBER4). An unprecedented yield of 1.01 g/L OmlA was ultimately achieved in a 5-L bioreactor following the scaling-up strategy of fixed oxygen mass transfer coefficient (kLa), and the produced OmlA antigen showed well-protective immunity against Actinobacillus pleuropneumoniae challenge. This result provides a rapid and reliable pipeline to achieve the hyper-production of OmlA, and possibly other recombinant vaccines, in C. glutamicum. KEY POINTS: • Established a holistic development process and applied it to potentiate the secretion of OmlA. • The secretion of OmlA reached an unprecedented yield of 1.01 g/L. • The recombinant OmlA antigen induced efficient protective immunity.


Assuntos
Actinobacillus pleuropneumoniae , Corynebacterium glutamicum , Animais , Reatores Biológicos , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Fermentação , Lipoproteína(a)/metabolismo , Suínos
17.
Synth Syst Biotechnol ; 7(2): 765-774, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35387228

RESUMO

Corynebacterium glutamicum represents an emerging recombinant protein expression factory due to its ideal features for protein secretion, but its applicability is harmed by the lack of an autoinduction system with tight regulation and high yield. Here, we propose a new recombinant protein manufacturing platform that leverages ethanol as both a delayed carbon source and an inducer. First, we reanalysed the native inducible promoter PICL from the acetate uptake operon and found that its limited capacity is the result of the inadequate translation initial architecture. The two strategies of bicistronic design and ribozyme-based insulator can ensure the high activity of this promoter. Next, through transcriptional engineering that alters transcription factor binding sites (TFBSs) and the first transcribed sequence, the truncated promoter PA256 with a dramatically higher transcription level was generated. When producing the superfolder green fluorescent protein (sfGFP) under 1% ethanol conditions, PA256 exhibited substantially lower protein accumulation in prophase but an approximately 2.5-fold greater final yield than the strong promoter PH36. This superior expression mode was further validated using two secreted proteins, camelid antibody fragment (VHH) and endoxylanase (XynA). Furthermore, utilizing CRISPRi technology, ethanol utilization blocking strains were created, and PA256 was shown to be impaired in the phosphotransacetylase (PTA) knockdown strains, indicating that ethanol metabolism into the tricarboxylic acid cycle is required for PA256 upregulation. Finally, this platform was applied to produce the "de novo design" protein NEO-2/15, and by introducing the N-propeptide of CspB, NEO-2/15 was effectively secreted with the accumulation 281 mg/L obtained after 24 h of shake-flask fermentation. To the best of our knowledge, this is the first report of NEO-2/15 secretory overexpression.

18.
Crit Rev Biotechnol ; 42(1): 73-92, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34256675

RESUMO

Sesquiterpenes are a large variety of terpene natural products, widely existing in plants, fungi, marine organisms, insects, and microbes. Value-added sesquiterpenes are extensively used in industries such as: food, drugs, fragrances, and fuels. With an increase in market demands and the price of sesquiterpenes, the biosynthesis of sesquiterpenes by microbial fermentation methods from renewable feedstocks is acquiring increasing attention. Synthetic biology provides robust tools of sesquiterpene production in microorganisms. This review presents a summary of metabolic engineering strategies on the hosts and pathway engineering for sesquiterpene production. Advances in synthetic biology provide new strategies on the creation of desired hosts for sesquiterpene production. Especially, metabolic engineering strategies for the production of sesquiterpenes such as: amorphadiene, farnesene, bisabolene, and caryophyllene are emphasized in: Escherichia coli, Saccharomyces cerevisiae, and other microorganisms. Challenges and future perspectives of the bioprocess for translating sesquiterpene production into practical industrial work are also discussed.


Assuntos
Engenharia Metabólica , Sesquiterpenos , Escherichia coli/genética , Saccharomyces cerevisiae/genética , Terpenos
19.
Protein Expr Purif ; 189: 105928, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34217803

RESUMO

The protease present in a host may reduce the yield and biological activity of heterologous proteins. In this study, we used protease overexpression and deletion strategies to examine the effect of the Clp protease system in Corynebacterium glutamicum on the recombinant protein and to produce a highly efficient heterologous protein expression host. In this study, we identified seven genes in the Clp protease family in Corynebacterium glutamicum ATCC 13032 through bioinformatics analysis, and studied their effects on the enhanced green fluorescent protein (EGFP) reporter protein. The fluorescence intensity of the knockout strain was significantly higher, and the effect of the clpS deletion strain was the most obvious. To verify the universal effect of the lack of clpS, the excellent industrial strain C. glutamicum 1.15647 was transformed to form recombinant 15647-ΔclpS. Based on the results, 15647-ΔclpS had a more significant effect on improving protein expression. Furthermore, recombinant human teriparatide (rhPTH) and variable domain of heavy chain of heavy-chain antibody (VHH) were selected to verify the universal applicability of the knockout strain for expressing heterologous proteins. Accordingly, we found that protease deficiency could increase the production of heterologous proteins. Finally, through a large-scale fermentation, the 15647-ΔclpS strain was used to produce VHH. Its yield was approximately 530 mg/L, which was 65% higher than that of WT-15647. In this study, a host that could effectively increase heterologous protein expression was successfully obtained.


Assuntos
Corynebacterium glutamicum/genética , Endopeptidase Clp/genética , Regulação Bacteriana da Expressão Gênica , Cadeias Pesadas de Imunoglobulinas/biossíntese , Teriparatida/metabolismo , Biologia Computacional/métodos , Corynebacterium glutamicum/enzimologia , Endopeptidase Clp/deficiência , Fermentação , Técnicas de Inativação de Genes , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/isolamento & purificação , Isoenzimas/deficiência , Isoenzimas/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Teriparatida/isolamento & purificação , Transgenes
20.
J Clin Med ; 12(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36614824

RESUMO

Fibromuscular dysplasia (FMD) is a non-atherosclerotic, non-inflammatory vascular disease involving small-to-medium-sized arteries. The characteristics of Chinese patients with FMD remain unclear. We retrospectively analyzed the data of patients with renal FMD who underwent percutaneous transluminal renal angioplasty (PTRA) for the first time at Fuwai Hospital between 2010 and 2021. The variables were selected through least absolute shrinkage and selection operator regression (LASSO), and logistic regression models were constructed to identify independent risk factors. A total of 116 patients (52 males, median age at diagnosis, 25.0 years) were enrolled. Elevated blood pressure was the leading complaint. After a median follow-up period of 18.0 months (interquartile range: 6.0-48.0 months), hypertension recurred in 34 patients and restenosis in nine patients, among whom four patients underwent secondary intervention and one patient underwent surgical revascularization. Bilateral renal artery involvement (odds ratio [OR]: 2.61, 95% confidence interval [CI]: 1.11-6.15; p = 0.028) and age at hypertension onset (OR: 0.93, 95% CI: 0.88-0.99; p = 0.018) were independent prognostic factors for adverse outcomes. The results indicate that patients with bilateral renal artery involvement and younger age at hypertension onset are more likely to have poorer clinical outcomes after PTRA, and should be more closely monitored.

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