1
|
Motta JF, Ferreira MRA, Waller SB, Rodrigues RR, Donassolo RA, Moreira Júnior C, Alves MLF, Feijó FD, Conceição FR. Immunogenicity of a pentavalent recombinant Escherichiacoli bacterin against enterotoxemia and botulism in sheep. Anaerobe 2024; 89:102895. [PMID: 39122140 DOI: 10.1016/j.anaerobe.2024.102895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 05/24/2024] [Accepted: 08/06/2024] [Indexed: 08/12/2024]
Abstract
INTRODUCTION Producing commercial bacterins/toxoids against Clostridium spp. is laborious and hazardous. Conversely, developing prototype vaccines using purified recombinant toxoids, though safe and effective, is both laborious and costly for application in production animals. OBJECTIVE Considering that inactivated recombinant Escherichiacoli (bacterin) is a simple, cost-effective, and to be safe solution, we evaluated, for the first time, a pentavalent formulation of recombinant bacterins containing the alpha, beta, and epsilon toxins of Clostridiumperfringens and C and D neurotoxins of Clostridiumbotulinum in sheep. METHODS Subcutaneously, 18 Texel sheep received two doses (200 μg of each antigen) of recombinant bacterin (n = 7) or purified recombinant antigens (n = 6) on days 0 and 28, while the control group (n = 5) did not receive an immunization. Sera samples from days 0 (before the 1st dose), 28 (before the 2nd dose), and 56, 84, and 112 were used for measuring IgG (indirect ELISA) and neutralizing antibodies (mouse serum neutralization). RESULTS Both formulations induced significant levels of IgG against all five toxins (p < 0.05) up to day 112, with peaks at days 28 and 56 post-immunization. The expected booster effect occurred only for the botulinum toxins. The neutralizing antibody titers were satisfactory against ETX (≥2 IU/ml for both formulations) and BoNT-D [5 IU/ml (bacterin) and 10 IU/ml (purified)]. CONCLUSION While adjustments are required, the recombinant bacterin platform holds great potential for polyvalent vaccines due to its straightforward, safe, and cost-effective production, establishing it as a user-friendly technology for the veterinary immunobiological industry.
Collapse
Affiliation(s)
- Jaqueline Freitas Motta
- Programa de Pós-Graduação em Veterinária, Faculdade de Veterinária, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil
| | - Marcos Roberto A Ferreira
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil.
| | - Stefanie Bressan Waller
- Programa de Pós-Graduação em Veterinária, Faculdade de Veterinária, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil; Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil
| | - Rafael Rodrigues Rodrigues
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil
| | - Rafael Amaral Donassolo
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil
| | - Clóvis Moreira Júnior
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil
| | - Mariliana Luiza Ferreira Alves
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil; Instituto Federal Sul-rio-grandense (IFSul), Campus Pelotas, Pelotas, RS, Brazil
| | - Fernanda Dornelles Feijó
- Departamento de Zootecnia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
| | - Fabricio Rochedo Conceição
- Programa de Pós-Graduação em Veterinária, Faculdade de Veterinária, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil; Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas (UFPEL), Pelotas, RS, Brazil
| |
Collapse
|
2
|
Moreira C, Rodrigues RR, da Cunha CEP, Donassolo RA, Ferreira MRA, Finger PF, Oliveira HGS, da Cruz KP, Moreira ÂN, Salvarani FM, Conceição FR. Evaluation of long-term immune response in cattle to botulism using a recombinant E. coli bacterin formulated with Montanide™ ISA 50 and aluminum hydroxide adjuvants. Microb Pathog 2024; 189:106596. [PMID: 38395317 DOI: 10.1016/j.micpath.2024.106596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 02/08/2024] [Accepted: 02/20/2024] [Indexed: 02/25/2024]
Abstract
Botulism is a severe disease caused by potent botulinum neurotoxins (BoNTs) produced by Clostridium botulinum. This disease is associated with high-lethality outbreaks in cattle, which have been linked to the ingestion of preformed BoNT serotypes C and D, emphasizing the need for effective vaccines. The potency of current commercial toxoids (formaldehyde-inactivated BoNTs) is assured through tests in guinea pigs according to government regulatory guidelines, but their short-term immunity raises concerns. Recombinant vaccines containing the receptor-binding domain have demonstrated potential for eliciting robust protective immunity. Previous studies have demonstrated the safety and effectiveness of recombinant E. coli bacterin, eliciting high titers of neutralizing antibodies against C. botulinum and C. perfringens in target animal species. In this study, neutralizing antibody titers in cattle and the long-term immune response against BoNT/C and D were used to assess the efficacy of the oil-based adjuvant compared with that of the aluminum hydroxide adjuvant in cattle. The vaccine formulation containing Montanide™ ISA 50 yielded significantly higher titers of neutralizing antibody against BoNT/C and D (8.64 IU/mL and 9.6 IU/mL, respectively) and induced an immune response that lasted longer than the response induced by aluminum, extending between 30 and 60 days. This approach represents a straightforward, cost-effective strategy for recombinant E. coli bacterin, enhancing both the magnitude and duration of the immune response to botulism.
Collapse
Affiliation(s)
- Clovis Moreira
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, CEP 96160-000, Brazil.
| | - Rafael R Rodrigues
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, CEP 96160-000, Brazil
| | - Carlos E P da Cunha
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, CEP 96160-000, Brazil
| | - Rafael A Donassolo
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, CEP 96160-000, Brazil
| | - Marcos R A Ferreira
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, CEP 96160-000, Brazil
| | - Paula F Finger
- Curso de Medicina Veterinária, Universidade Federal do Pampa, Uruguaiana, Rio Grande do Sul, CEP 97508-000, Brazil
| | - Hanna G S Oliveira
- Instituto de Medicina Veterinária, Universidade Federal do Pará, Castanhal, Pará, CEP 68740-970, Brazil
| | - Karoline P da Cruz
- Instituto de Medicina Veterinária, Universidade Federal do Pará, Castanhal, Pará, CEP 68740-970, Brazil
| | - Ângela N Moreira
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, CEP 96160-000, Brazil
| | - Felipe M Salvarani
- Instituto de Medicina Veterinária, Universidade Federal do Pará, Castanhal, Pará, CEP 68740-970, Brazil
| | - Fabricio R Conceição
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, CEP 96160-000, Brazil
| |
Collapse
|
3
|
Rodrigues Rodrigues R, Freitas Motta J, Alves Ferreira MR, Moreira Júnior C, Ferreira Alves ML, Costa AV, Andrade Bilhalva M, Amaral Donassolo R, Cancela Galvão C, Silva Martins FM, Masiero Salvarani F, Rochedo Conceição F. Immunization of sheep with a recombinant vaccine containing immunogenic nontoxic domains of Clostridium perfringens alpha and beta toxins. Microb Pathog 2023; 182:106269. [PMID: 37516212 DOI: 10.1016/j.micpath.2023.106269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/23/2023] [Accepted: 07/24/2023] [Indexed: 07/31/2023]
Abstract
Clostridium perfringens (types A and C) can cause several diseases by secreting alpha (CPA) and beta (CPB) exotoxins in the gastrointestinal tract. Although vaccination is the main measure of immunization against C. perfringens, available vaccines have limitations in terms of productivity and safety. Thus, recombinant vaccines are an important, more effective, practical, and safer strategy in the immunization of animals. In this study, we evaluated the immunization of sheep with recombinant Escherichia coli bacterins expressing CPA and CPB complete proteins (co-administered), the immunogenic nontoxic domains rCPA-C247-370 and rCPB-C143-311 co-administered or fused as a bivalent chimera (rCPBcAc). For this, in silico analysis was performed to design rCPBcAc, considering the stability of the mRNA (-278.80 kcal/mol), the degree of antigenicity (0.7557), the epitopes of the B cell ligand, and different physicochemical characteristics. All proteins were expressed in vitro. In vivo, animals vaccinated with the co-administered antigens rCPA + rCPB and rCPA-C+ rCPB-C (200 μg each) had mean CPA and CPB neutralizing antitoxin titers of 4, 10, 4.8, and 14.4 IU/mL, respectively, while those vaccinated with 200 μg of rCPBcAc chimera (approximately 100 μg of each antigen) had titers of <4 and 12 IU/mL of CPA and CPB antitoxins, respectively, 56 days after the administration of the first dose. In addition, the chimera was considered to be immunogenic for inducing antitoxin titers using the half dose. In this study, we presented a new recombinant antigen potentially applicable for vaccines against the CPA and CPB toxins for preventing diseases caused by Clostridium perfringens.
Collapse
Affiliation(s)
- Rafael Rodrigues Rodrigues
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil.
| | - Jaqueline Freitas Motta
- Faculdade de Veterinária, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, Brazil
| | | | - Clóvis Moreira Júnior
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil
| | - Mariliana Luiza Ferreira Alves
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil; Instituto Federal Sul-rio-grandense, IFSul, Campus Pelotas, RS, Brazil
| | - Ana Vitória Costa
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil
| | - Miguel Andrade Bilhalva
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil
| | - Rafael Amaral Donassolo
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil
| | - Cleideanny Cancela Galvão
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil
| | | | | | - Fabricio Rochedo Conceição
- Centro de Desenvolvimento Tecnológico, Biotecnologia, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil; Faculdade de Veterinária, Universidade Federal de Pelotas, Pelotas, Rio Grande do Sul, Brazil
| |
Collapse
|
4
|
Du J, Meki I, Li Q, Liu Y, Zhu Z, Pan C, Xia Y, Fu L, Yang L, Zhang S, Yin C, Luo Y, Wang T, Liu B, Chen X. A non-toxic recombinant Clostridium septicum α toxin induces protective immunity in mice and rabbits. Toxicon 2023; 233:107234. [PMID: 37543293 DOI: 10.1016/j.toxicon.2023.107234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 08/07/2023]
Abstract
Clostridium septicum alpha toxin (CSA) plays significant roles in ruminant's braxy. Genetically engineered CSA has been shown to function as a potential vaccine candidate in the prevention of the disease caused by Clostridium septicum. In the present study, we synthesized a non-toxic recombinant, rCSAm4/TMD by introducing four amino acid substitutions (C86L/N296A/H301A/W342A) and 11-amino-acid deletion (residues 212 to 222). Compared to recombinant CSA, rCSAm4/TMD showed no cytotoxicity to MDCK cells and was not fatal to mice. Moreover, rCSAm4/TMD could protect immunized mice against 5 × mouse LD100 (100% lethal dose) of crude CSA without obvious pathological change. Most importantly, rabbits immunized with rCSAm4/TMD produced high titers of neutralizing antibodies which protected the rabbits against crude CSA challenge. These data suggest that genetically detoxified rCSAm4/TMD is a potential subunit vaccine candidate against braxy.
Collapse
Affiliation(s)
- Jige Du
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China
| | - Irene Meki
- International Atomic Energy Agency, Vienna, Austria
| | - Qianlin Li
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China
| | - Ying Liu
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China
| | - Zhen Zhu
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China
| | - Chenfan Pan
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China
| | - Yingju Xia
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China
| | - Lizhi Fu
- Chongqing Academy of Animal Sciences, Chongqing, 402460, China
| | - Liu Yang
- Chongqing Academy of Animal Sciences, Chongqing, 402460, China
| | - Suhui Zhang
- Chongqing Academy of Animal Sciences, Chongqing, 402460, China
| | - Chunsheng Yin
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China
| | - Yufeng Luo
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China
| | - Tuanjie Wang
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China.
| | - Bo Liu
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China; International Atomic Energy Agency, Vienna, Austria.
| | - Xiaoyun Chen
- China Institute of Veterinary Drug Control, Beijing, People's Republic of China.
| |
Collapse
|
5
|
Efremenko E, Aslanli A, Lyagin I. Advanced Situation with Recombinant Toxins: Diversity, Production and Application Purposes. Int J Mol Sci 2023; 24:ijms24054630. [PMID: 36902061 PMCID: PMC10003545 DOI: 10.3390/ijms24054630] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/14/2023] [Accepted: 02/20/2023] [Indexed: 03/04/2023] Open
Abstract
Today, the production and use of various samples of recombinant protein/polypeptide toxins is known and is actively developing. This review presents state-of-the-art in research and development of such toxins and their mechanisms of action and useful properties that have allowed them to be implemented into practice to treat various medical conditions (including oncology and chronic inflammation applications) and diseases, as well as to identify novel compounds and to detoxify them by diverse approaches (including enzyme antidotes). Special attention is given to the problems and possibilities of the toxicity control of the obtained recombinant proteins. The recombinant prions are discussed in the frame of their possible detoxification by enzymes. The review discusses the feasibility of obtaining recombinant variants of toxins in the form of protein molecules modified with fluorescent proteins, affine sequences and genetic mutations, allowing us to investigate the mechanisms of toxins' bindings to their natural receptors.
Collapse
Affiliation(s)
- Elena Efremenko
- Correspondence: ; Tel.: +7-(495)-939-3170; Fax: +7-(495)-939-5417
| | | | | |
Collapse
|
6
|
Alves MLF, Ferreira MRA, Rodrigues RR, Conceição FR. Clostridium haemolyticum, a review of beta toxin and insights into the antigen design for vaccine development. Mol Immunol 2022; 148:45-53. [PMID: 35665660 DOI: 10.1016/j.molimm.2022.05.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 05/01/2022] [Accepted: 05/16/2022] [Indexed: 01/03/2023]
Abstract
Phospholipases C (PLCs) represent an important group of lethal toxins produced by pathogenic bacteria of the Clostridium genus, including the beta toxin of C. haemolyticum. Bacillary hemoglobinuria in cattle and sheep is the main disease caused by this pathogen and its incidence can be reduced by annual vaccination of herds. Currently, widely used vaccines depend on cultivating the pathogen and obtaining high concentrations of the toxin, disadvantages that can be overcome with the use of recombinant vaccines. In the development of this new generation of immunizing agents, identifying and understanding the structural and immunological aspects of the antigen are crucial steps, but despite this, the beta toxin is poorly characterized. Fortunately, the time and resources required for these investigations can be reduced using immunoinformatics. To advance the development of recombinant vaccines, in addition to a brief review of the structural and immunological aspects of beta toxin, this work provides in silico mapping of immunodominant regions to guide future vaccinology studies against C. haemolyticum. A review of alternatives to overcome the limitations of beta toxin vaccines (conventional or recombinant) is also proposed.
Collapse
Affiliation(s)
- Mariliana Luiza Ferreira Alves
- Instituto Federal Sul-rio-grandense - IFSUL, Praça Vinte de Setembro, 455, Centro, Pelotas CEP 96.015-360, RS, Brazil; Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, CP 354, Pelotas CEP 96.160-000, RS, Brazil.
| | - Marcos Roberto Alves Ferreira
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, CP 354, Pelotas CEP 96.160-000, RS, Brazil
| | - Rafael Rodrigues Rodrigues
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, CP 354, Pelotas CEP 96.160-000, RS, Brazil
| | - Fabricio Rochedo Conceição
- Centro de Desenvolvimento Tecnológico, Núcleo de Biotecnologia, Universidade Federal de Pelotas, CP 354, Pelotas CEP 96.160-000, RS, Brazil
| |
Collapse
|
7
|
Measurement over 1 Year of Neutralizing Antibodies in Cattle Immunized with Trivalent Vaccines Recombinant Alpha, Beta and Epsilon of Clostridium perfringens. Toxins (Basel) 2021; 13:toxins13090594. [PMID: 34564599 PMCID: PMC8470993 DOI: 10.3390/toxins13090594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/03/2021] [Accepted: 08/06/2021] [Indexed: 11/17/2022] Open
Abstract
The alpha (CPA), beta (CPB) and epsilon (ETX) toxins of Clostridium perfringens are responsible for causing diseases that are difficult to eradicate and have lethal potential in production animals. Vaccination of herds is still the best control strategy. Recombinant clostridial vaccines have shown good success at inducing neutralizing antibody titers and appear to be a viable alternative to the conventional production of commercial clostridial toxoids. Research is still needed on the longevity of the humoral immune response induced by recombinant proteins in immunized animals, preferably in target species. The objective of this study was to measure the humoral immune response of cattle immunized with trivalent vaccines containing the recombinant proteins alpha (rCPA), beta (rCPB) and epsilon (rETX) of C. perfringens produced in Escherichia coli at three different concentrations (100, 200, and 400 µg) of each protein for 12 months. The recombinant vaccines containing 200 (RV2) and 400 µg (RV3) yielded statistically similar results at 56 days. They performed better throughout the study period because they induced higher neutralizing antibody titers and were detectable for up to 150 and 180 days, respectively. Regarding industrial-scale production, RV2 would be the most economical and viable formulation as it achieved results similar to RV3 at half the concentration of recombinant proteins in its formulation. However, none of the vaccines tested induced the production of detectable antibody titers on day 365 of the experiment, the time of revaccination typically recommended in vaccination protocols. Thus, reiterating the need for research in the field of vaccinology to achieve greater longevity of the humoral immune response against these clostridial toxins in animals, in addition to the need to discuss the vaccine schedules and protocols adopted in cattle production.
Collapse
|
8
|
Hussain H, McKenzie EA, Robinson AM, Gingles NA, Marston F, Warwicker J, Dickson AJ. Predictive approaches to guide the expression of recombinant vaccine targets in Escherichia coli: a case study presentation utilising Absynth Biologics Ltd. proprietary Clostridium difficile vaccine antigens. Appl Microbiol Biotechnol 2021; 105:5657-5674. [PMID: 34180005 PMCID: PMC8285303 DOI: 10.1007/s00253-021-11405-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/02/2021] [Accepted: 06/08/2021] [Indexed: 12/01/2022]
Abstract
Bacterial expression systems remain a widely used host for recombinant protein production. However, overexpression of recombinant target proteins in bacterial systems such as Escherichia coli can result in poor solubility and the formation of insoluble aggregates. As a consequence, numerous strategies or alternative engineering approaches have been employed to increase recombinant protein production. In this case study, we present the strategies used to increase the recombinant production and solubility of ‘difficult-to-express’ bacterial antigens, termed Ant2 and Ant3, from Absynth Biologics Ltd.’s Clostridium difficile vaccine programme. Single recombinant antigens (Ant2 and Ant3) and fusion proteins (Ant2-3 and Ant3-2) formed insoluble aggregates (inclusion bodies) when overexpressed in bacterial cells. Further, proteolytic cleavage of Ant2-3 was observed. Optimisation of culture conditions and changes to the construct design to include N-terminal solubility tags did not improve antigen solubility. However, screening of different buffer/additives showed that the addition of 1–15 mM dithiothreitol alone decreased the formation of insoluble aggregates and improved the stability of both Ant2 and Ant3. Structural models were generated for Ant2 and Ant3, and solubility-based prediction tools were employed to determine the role of hydrophobicity and charge on protein production. The results showed that a large non-polar region (containing hydrophobic amino acids) was detected on the surface of Ant2 structures, whereas positively charged regions (containing lysine and arginine amino acids) were observed for Ant3, both of which were associated with poor protein solubility. We present a guide of strategies and predictive approaches that aim to guide the construct design, prior to expression studies, to define and engineer sequences/structures that could lead to increased expression and stability of single and potentially multi-domain (or fusion) antigens in bacterial expression systems.
Collapse
Affiliation(s)
- Hirra Hussain
- Manchester Institute of Biotechnology, University of Manchester, M1 7DN, Manchester, UK
| | - Edward A McKenzie
- Manchester Institute of Biotechnology, University of Manchester, M1 7DN, Manchester, UK
| | - Andrew M Robinson
- Absynth Biologics Ltd., BioHub, Alderley Park, Cheshire, SK10 4TG, UK.,Evotec Limited, Biohub, Alderley Park, Cheshire, England, SK10 4TG, UK
| | - Neill A Gingles
- Absynth Biologics Ltd., BioHub, Alderley Park, Cheshire, SK10 4TG, UK.,metaLinear Limited, Biohub, Alderley Park, Cheshire, England, SK10 4TG, UK
| | - Fiona Marston
- Absynth Biologics Ltd., BioHub, Alderley Park, Cheshire, SK10 4TG, UK.,Liverpool School of Tropical Medicine, L3 5QA, Liverpool, UK
| | - Jim Warwicker
- Manchester Institute of Biotechnology, University of Manchester, M1 7DN, Manchester, UK
| | - Alan J Dickson
- Manchester Institute of Biotechnology, University of Manchester, M1 7DN, Manchester, UK.
| |
Collapse
|