scholarly journals Recent Developments of Recombinant Protein Expression for Therapeutic Purposes

2021 ◽  
Vol 3 (4) ◽  
Author(s):  
Anam Amir

In the most recent seven to eight years, the therapeutic recombinant proteins have rapidly expanded in the biotechnology domain due to its wide variety of needs. There has been significant development in the mammalian expression system for fine purification and increased level of expressed recombinant proteins [1,2]. Many drugs like tetracycline have been demonstrated on the Chinese Hamster Ovary cell line for promising multi control strategies and effective cytotoxicity. Mammalian expression system improves the proper glycosylation of recombinant proteins which are very helpful to increase solubility of product [3-6].             Meanwhile on the prokaryotic expression system, E. coli has proven to be an easier to handle, friendly and economical strain [2]. Recently these expression systems are using to work on antibody fragment productions and their proper folding with co-expression of chaperones [7]. Moreover E. coli has been used for the production of cancer cell penetrating peptides which promises the targeted delivery of drugs to specific effector cells only.  Yeast systems are also being used for the antibody fragments production and the high level production of insulin. Interestingly cell free expression systems are also participating in this game and that would be very fascinating to see in the coming years about cell extract medium for production of high level recombinant protein [8, 9]. Purification and optimization of recombinant protein has always been a challenging situation for scientists and they paid more attention to increase the overall yield of the product. Many affinity chromatography techniques has been introduced for efficient purification of protein of interest [10]. Despite these research and developments in methodologies to produce and purify the recombinant therapeutic protein, scientists still face the hurdles and challenges with all expression systems. Rationally E. coli produces inclusion bodies and many mammalian cell types do not show the same results with the same recombinant protein. [11]. So there is a requirement for adding the appropriate features to the expression systems focused to better improvising recovery, production and purification of recombinant protein. Copyright(c) The Author

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Fei Du ◽  
Yun-Qi Liu ◽  
Ying-Shuang Xu ◽  
Zi-Jia Li ◽  
Yu-Zhou Wang ◽  
...  

AbstractEscherichia coli is the most widely used bacterium in prokaryotic expression system for the production of recombinant proteins. In BL21 (DE3), the gene encoding the T7 RNA polymerase (T7 RNAP) is under control of the strong lacUV5 promoter (PlacUV5), which is leakier and more active than wild-type lac promoter (PlacWT) under certain growth conditions. These characteristics are not advantageous for the production of those recombinant proteins with toxic or growth-burdened. On the one hand, leakage expression of T7 RNAP leads to rapid production of target proteins under non-inducing period, which sucks resources away from cellular growth. Moreover, in non-inducing or inducing period, high expression of T7 RNAP production leads to the high-production of hard-to-express proteins, which may all lead to loss of the expression plasmid or the occurrence of mutations in the expressed gene. Therefore, more BL21 (DE3)-derived variant strains with rigorous expression and different expression level of T7 RNAP should be developed. Hence, we replaced PlacUV5 with other inducible promoters respectively, including arabinose promoter (ParaBAD), rhamnose promoter (PrhaBAD), tetracycline promoter (Ptet), in order to optimize the production of recombinant protein by regulating the transcription level and the leakage level of T7 RNAP. Compared with BL21 (DE3), the constructed engineered strains had higher sensitivity to inducers, among which rhamnose and tetracycline promoters had the lowest leakage ability. In the production of glucose dehydrogenase (GDH), a protein that causes host autolysis, the engineered strain BL21 (DE3::ara) exhibited higher biomass, cell survival rate and foreign protein expression level than that of BL21 (DE3). In addition, these engineered strains had been successfully applied to improve the production of membrane proteins, including E. coli cytosine transporter protein (CodB), the E. coli membrane protein insertase/foldase (YidC), and the E. coli F-ATPase subunit b (Ecb). The engineered strains constructed in this paper provided more host choices for the production of recombinant proteins.


2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Ryan Anderton ◽  
Bruno Meloni ◽  
Frank Mastaglia ◽  
Sherif Boulos

AbstractSpinal muscular atrophy (SMA), the most common genetic cause of infant death, is a neurodegenerative disorder affecting motor neurons. SMA results from a loss in full-length survival of motor neuron (SMN) protein due to deletions/mutations in the SMN1 gene. In this study, we assessed the ability of cell-penetrating peptides (CPP) to deliver recombinant SMN protein to cultured neurons as a prelude for a potential therapeutic to treat SMA. Firstly, we confirmed that E. coli produced recombinant GFP protein fused to TAT (YGRKKRRQRRR; TAT-GFP) transduced rat cortical neurons in a concentration dependent manner. However, due to low yields of recombinant TATSMN protein obtainable from E. coli, we investigated the potential of a modified TAT (TATκ: YARKAARQARA) or R9 (RRRRRRRRR) peptide downstream of the fibronectin (FIB) secretory signal peptide to generate recombinant CPP-fused SMN protein. While U251 cells transduced with an adenoviral vector expressing CMV-FIB-TATκ-SMN secreted recombinant TATκ-SMN protein, we did not detect TATκ-SMN protein transduction of cortical neurons. Further, purified TATκ-SMN was unable to transduce SH-SY5Y cells, nor block apoptosis following LY294002 treatment of these cells. Our findings indicate that TATκ is not a suitable CPP to deliver SMN protein to neurons. Nonetheless, we have developed a novel method to generate full-length recombinant SMN protein using a mammalian expression system, which can be used to explore the application of other CPPs to deliver SMN protein as a treatment for SMA.


2021 ◽  
Vol 12 ◽  
Author(s):  
Gema Lozano Terol ◽  
Julia Gallego-Jara ◽  
Rosa Alba Sola Martínez ◽  
Adrián Martínez Vivancos ◽  
Manuel Cánovas Díaz ◽  
...  

Recombinant protein production for medical, academic, or industrial applications is essential for our current life. Recombinant proteins are obtained mainly through microbial fermentation, with Escherichia coli being the host most used. In spite of that, some problems are associated with the production of recombinant proteins in E. coli, such as the formation of inclusion bodies, the metabolic burden, or the inefficient translocation/transport system of expressed proteins. Optimizing transcription of heterologous genes is essential to avoid these drawbacks and develop competitive biotechnological processes. Here, expression of YFP reporter protein is evaluated under the control of four promoters of different strength (PT7lac, Ptrc, Ptac, and PBAD) and two different replication origins (high copy number pMB1′ and low copy number p15A). In addition, the study has been carried out with the E. coli BL21 wt and the ackA mutant strain growing in a rich medium with glucose or glycerol as carbon sources. Results showed that metabolic burden associated with transcription and translation of foreign genes involves a decrease in recombinant protein expression. It is necessary to find a balance between plasmid copy number and promoter strength to maximize soluble recombinant protein expression. The results obtained represent an important advance on the most suitable expression system to improve both the quantity and quality of recombinant proteins in bioproduction engineering.


2020 ◽  
Author(s):  
Artur Schuller ◽  
Monika Cserjan-Puschmann ◽  
Christopher Tauer ◽  
Johanna Jarmer ◽  
Martin Wagenknecht ◽  
...  

Abstract Background The genome-integrated T7 expression system offers significant advantages, in terms of productivity and product quality, even when expressing the gene of interest (GOI) from a single copy of. Compared to plasmid-based expression systems, this system does not incur a plasmid-mediated metabolic load, and it does not vary the dosage of the GOI during the production process. However, long-term production with T7 expression system leads to a rapidly growing non-producing population, because the T7 RNA polymerase (RNAP) is prone to mutations. The present study aimed to investigate whether two σ 70 promoters, which were recognized by the Escherichia coli host RNAP, might be suitable in genome-integrated expression systems. We applied a promoter engineering strategy that allowed control of expressing the model protein, GFP, by introducing lac operators ( lacO ) into the constitutive T5 and A1 promoter sequences. Results We showed that, in genome-integrated E. coli expression systems that used σ 70 promoters, the number of lacO sites must be well balanced. Promoters containing three and two lacO sites exhibited low basal expression, but resulted in a complete stop in recombinant protein production in partially induced cultures. In contrast, expression systems regulated by a single lacO site and the lac repressor element, lacI Q , on the same chromosome caused very low basal expression, were highly efficient in recombinant protein production, and enables fine-tuning of gene expression levels on a cellular level. Conclusions Based on our results, we hypothesized that this phenomenon was associated with the autoregulation of the lac repressor protein, LacI. We reasoned that the affinity of LacI for the lacO sites of the GOI must be lower than the affinity of LacI to the lacO sites of the endogenous lac operon; otherwise, LacI autoregulation could not take place, and the lack of LacI autoregulation would lead to a disturbance in lac repressor-mediated regulation of transcription. By exploiting the mechanism of LacI autoregulation, we created a novel E. coli expression system for use in recombinant protein production, synthetic biology, and metabolic engineering applications.


2019 ◽  
Author(s):  
Artur Schuller ◽  
Monika Cserjan-Puschmann ◽  
Christopher Tauer ◽  
Johanna Jarmer ◽  
Martin Wagenknecht ◽  
...  

Abstract Background The genome-integrated T7 expression system offers significant advantages, in terms of productivity and product quality, even when expressing the gene of interest (GOI) from a single copy of. Compared to plasmid-based expression systems, this system does not incur a plasmid-mediated metabolic load, and it does not vary the dosage of the GOI during the production process. However, long-term production with T7 expression system leads to a rapidly growing non-producing population, because the T7 RNA polymerase (RNAP) is prone to mutations. The present study aimed to investigate whether two σ 70 promoters, which were recognized by the Escherichia coli host RNAP, might be suitable in genome-integrated expression systems. We applied a promoter engineering strategy that allowed control of expressing the model protein, GFP, by introducing lac operators ( lacO ) into the constitutive T5 and A1 promoter sequences.Results We showed that, in genome-integrated E. coli expression systems that used σ 70 promoters, the number of lacO sites must be well balanced. Promoters containing three and two lacO sites exhibited low basal expression, but resulted in a complete stop in recombinant protein production in partially induced cultures. In contrast, expression systems regulated by a single lacO site and the lac repressor element, lacI Q , on the same chromosome caused very low basal expression, were highly efficient in recombinant protein production, and enables fine-tuning of gene expression levels on a cellular level.Conclusions Based on our results, we hypothesized that this phenomenon was associated with the autoregulation of the lac repressor protein, LacI. We reasoned that the affinity of LacI for the lacO sites of the GOI must be lower than the affinity of LacI to the lacO sites of the endogenous lac operon; otherwise, LacI autoregulation could not take place, and the lack of LacI autoregulation would lead to a disturbance in lac repressor-mediated regulation of transcription. By exploiting the mechanism of LacI autoregulation, we created a novel E. coli expression system for use in recombinant protein production, synthetic biology, and metabolic engineering applications.


2006 ◽  
Vol 72 (8) ◽  
pp. 5225-5231 ◽  
Author(s):  
Emmanuel Frachon ◽  
Vincent Bondet ◽  
Hélène Munier-Lehmann ◽  
Jacques Bellalou

ABSTRACT A multiple microfermentor battery was designed for high-throughput recombinant protein production in Escherichia coli. This novel system comprises eight aerated glass reactors with a working volume of 80 ml and a moving external optical sensor for measuring optical densities at 600 nm (OD600) ranging from 0.05 to 100 online. Each reactor can be fitted with miniature probes to monitor temperature, dissolved oxygen (DO), and pH. Independent temperature regulation for each vessel is obtained with heating/cooling Peltier devices. Data from pH, DO, and turbidity sensors are collected on a FieldPoint (National Instruments) I/O interface and are processed and recorded by a LabVIEW program on a personal computer, which enables feedback control of the culture parameters. A high-density medium formulation was designed, which enabled us to grow E. coli to OD600 up to 100 in batch cultures with oxygen-enriched aeration. Accordingly, the biomass and the amount of recombinant protein produced in a 70-ml culture were at least equivalent to the biomass and the amount of recombinant protein obtained in a Fernbach flask with 1 liter of conventional medium. Thus, the microfermentor battery appears to be well suited for automated parallel cultures and process optimization, such as that needed for structural genomics projects.


2014 ◽  
Vol 185 ◽  
pp. S70
Author(s):  
Boguslaw Lupa ◽  
Krzysztof Stawujak ◽  
Igor Rozanski ◽  
Justyna Stec-Niemczyk

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Jan Weber ◽  
Zhaopeng Li ◽  
Ursula Rinas

Abstract Background Recently it was shown that production of recombinant proteins in E. coli BL21(DE3) using pET based expression vectors leads to metabolic stress comparable to a carbon overfeeding response. Opposite to original expectations generation of energy as well as catabolic provision of precursor metabolites were excluded as limiting factors for growth and protein production. On the contrary, accumulation of ATP and precursor metabolites revealed their ample formation but insufficient withdrawal as a result of protein production mediated constraints in anabolic pathways. Thus, not limitation but excess of energy and precursor metabolites were identified as being connected to the protein production associated metabolic burden. Results Here we show that the protein production associated accumulation of energy and catabolic precursor metabolites is not unique to E. coli BL21(DE3) but also occurs in E. coli K12. Most notably, it was demonstrated that the IPTG-induced production of hFGF-2 using a tac-promoter based expression vector in the E. coli K12 strain TG1 was leading to persistent accumulation of key regulatory molecules such as ATP, fructose-1,6-bisphosphate and pyruvate. Conclusions Excessive energy generation, respectively, accumulation of ATP during recombinant protein production is not unique to the BL21(DE3)/T7 promoter based expression system but also observed in the E. coli K12 strain TG1 using another promoter/vector combination. These findings confirm that energy is not a limiting factor for recombinant protein production. Moreover, the data also show that an accelerated glycolytic pathway flux aggravates the protein production associated “metabolic burden”. Under conditions of compromised anabolic capacities cells are not able to reorganize their metabolic enzyme repertoire as required for reduced carbon processing.


Sign in / Sign up

Export Citation Format

Share Document