1
|
Prías-Blanco M, Chappell TM, Freed EF, Illa-Berenguer E, Eckert CA, Parrott WA. An Agrobacterium strain auxotrophic for methionine is useful for switchgrass transformation. Transgenic Res 2022; 31:661-676. [PMID: 36239844 PMCID: PMC9747830 DOI: 10.1007/s11248-022-00328-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 09/26/2022] [Indexed: 01/20/2023]
Abstract
Auxotrophic strains of Agrobacterium tumefaciens can contribute to the development of more efficient transformation systems, especially for crops historically considered recalcitrant. Homologous recombination was used to derive methionine auxotrophs of two common A. tumefaciens strains, LBA4404 and EHA105. The EHA105 strains were more efficient for switchgrass transformation, while both the EHA105 and LBA4404 strains worked equally well for the rice control. Event quality, as measured by transgene copy number, was not affected by auxotrophy, but was higher for the LBA4404 strains than the EHA105 strains. Ultimately, the use of auxotrophs reduced bacterial overgrowth during co-cultivation and decreased the need for antibiotics.
Collapse
Affiliation(s)
- Mónica Prías-Blanco
- Institute of Plant Breeding, Genetics and Genomics, University of Georgia, Athens, GA, USA
| | - Timothy M Chappell
- Institute of Plant Breeding, Genetics and Genomics, University of Georgia, Athens, GA, USA
| | - Emily F Freed
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, CO, USA
| | | | - Carrie A Eckert
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, CO, USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Wayne A Parrott
- Institute of Plant Breeding, Genetics and Genomics, University of Georgia, Athens, GA, USA.
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA.
- Department of Crop and Soil Sciences, University of Georgia, Athens, GA, USA.
| |
Collapse
|
2
|
Bahramnejad B, Naji M, Bose R, Jha S. A critical review on use of Agrobacterium rhizogenes and their associated binary vectors for plant transformation. Biotechnol Adv 2019; 37:107405. [PMID: 31185263 DOI: 10.1016/j.biotechadv.2019.06.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/27/2019] [Accepted: 06/04/2019] [Indexed: 12/21/2022]
Abstract
Agrobacterium rhizogenes, along with A. tumefaciens, has been used to affect genetic transformation in plants for many years. Detailed studies conducted in the past have uncovered the basic mechanism of foreign gene transfer and the implication of Ri/Ti plasmids in this process. A number of reviews exist describing the usage of binary vectors with A. tumefaciens, but no comprehensive account of the numerous binary vectors employed with A. rhizogenes and their successful applications has been published till date. In this review, we recollect a brief history of development of Ri-plasmid/Ri-T-DNA based binary vectors systems and their successful implementation with A. rhizogenes for different applications. The modification of native Ri plasmid to introduce foreign genes followed by development of binary vector using Ri plasmid and how it facilitated rapid and feasible genetic manipulation, earlier impossible with native Ri plasmid, have been discussed. An important milestone was the development of inducible plant expressing promoter systems which made expression of toxic genes in plant systems possible. The successful application of binary vectors in conjunction with A. rhizogenes in gene silencing and genome editing studies which are relatively newer developments, demonstrating the amenability and adaptability of hairy roots systems to make possible studying previously intractable research areas have been summarized in the present review.
Collapse
Affiliation(s)
- Bahman Bahramnejad
- Department of Agronomy and Plant Breeding, University of Kurdistan, Sanandaj, Kurdistan 66177-15175, Iran.
| | - Mohammad Naji
- Department of Agronomy and Plant Breeding, University of Kurdistan, Sanandaj, Kurdistan 66177-15175, Iran
| | - Rahul Bose
- Department of Genetics, University of Calcutta, Kolkata 700019, India
| | - Sumita Jha
- Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700 019, India
| |
Collapse
|
3
|
Sukenik SC, Karuppanan K, Li Q, Lebrilla CB, Nandi S, McDonald KA. Transient Recombinant Protein Production in Glycoengineered Nicotiana benthamiana Cell Suspension Culture. Int J Mol Sci 2018; 19:E1205. [PMID: 29659495 PMCID: PMC5979281 DOI: 10.3390/ijms19041205] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Revised: 04/06/2018] [Accepted: 04/09/2018] [Indexed: 11/17/2022] Open
Abstract
Transient recombinant protein production is a promising alternative to stable transgenic systems, particularly for emergency situations in which rapid production of novel therapeutics is needed. In plants, Agrobacterium tumefaciens can be used as a gene delivery vector for transient expression. A potential barrier for plant-based production of human therapeutics is that different glycosylation patterns are found on plant and mammalian proteins. Since glycosylation can affect the efficacy, safety and stability of a therapeutic protein, methods to control glycan structures and distributions in plant-based systems would be beneficial. In these studies, we performed Agrobacterium-mediated transient expression in glycoengineered plant cell suspension cultures. To reduce the presence of plant-specific glycans on the product, we generated and characterized cell suspension cultures from β-1,2-xylosyltransferase and α-1,3-fucosyltransferase knockdown Nicotiana benthamiana. An anthrax decoy fusion protein was transiently produced in these glycoengineered plant cell suspension cultures through co-culture with genetically engineered Agrobacterium. The mass ratio of Agrobacterium to plant cells used was shown to impact recombinant protein expression levels. N-glycosylation analysis on the anthrax decoy fusion protein produced in glycoengineered N. benthamiana showed a dramatic reduction in plant-specific N-glycans. Overall, the results presented here demonstrate the feasibility of a simple, rapid and scalable process for transient production of recombinant proteins without plant-specific glycans in a glycoengineered plant cell culture host.
Collapse
Affiliation(s)
- Sara C Sukenik
- Department of Chemical Engineering, University of California, Davis, CA 95616, USA.
| | - Kalimuthu Karuppanan
- Department of Chemical Engineering, University of California, Davis, CA 95616, USA.
| | - Qiongyu Li
- Department of Chemistry, University of California, Davis, CA 95616, USA.
| | - Carlito B Lebrilla
- Department of Chemistry, University of California, Davis, CA 95616, USA.
- Department of Biochemistry and Molecular Medicine, University of California, Davis, CA 95616, USA.
- Foods for Health Institute, University of California, Davis, CA 95616, USA.
| | - Somen Nandi
- Department of Chemical Engineering, University of California, Davis, CA 95616, USA.
- Global HealthShare Initiative, University of California, Davis, CA 95616, USA.
| | - Karen A McDonald
- Department of Chemical Engineering, University of California, Davis, CA 95616, USA.
- Global HealthShare Initiative, University of California, Davis, CA 95616, USA.
| |
Collapse
|
4
|
Rosenthal SH, Diamos AG, Mason HS. An intronless form of the tobacco extensin gene terminator strongly enhances transient gene expression in plant leaves. PLANT MOLECULAR BIOLOGY 2018; 96:429-443. [PMID: 29429129 DOI: 10.1007/s11103-018-0708-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 02/01/2018] [Indexed: 05/24/2023]
Abstract
KEY MESSAGE We have found interesting features of a plant gene (extensin) 3' flanking region, including extremely efficient polyadenylation which greatly improves transient expression of transgenes when an intron is removed. Its use will greatly benefit studies of gene expression in plants, research in molecular biology, and applications for recombinant proteins. Plants are a promising platform for the production of recombinant proteins. To express high-value proteins in plants efficiently, the optimization of expression cassettes using appropriate regulatory sequences is critical. Here, we characterize the activity of the tobacco extensin (Ext) gene terminator by transient expression in Nicotiana benthamiana, tobacco, and lettuce. Ext is a member of the hydroxyproline-rich glycoprotein (HRGP) superfamily and constitutes the major protein component of cell walls. The present study demonstrates that the Ext terminator with its native intron removed increased transient gene expression up to 13.5-fold compared to previously established terminators. The enhanced transgene expression was correlated with increased mRNA accumulation and reduced levels of read-through transcripts, which could impair gene expression. Analysis of transcript 3'-ends found that the majority of polyadenylated transcripts were cleaved at a YA dinucleotide downstream from a canonical AAUAAA motif and a UG-rich region, both of which were found to be highly conserved among related extensin terminators. Deletion of either of these regions eliminated most of the activity of the terminator. Additionally, a 45 nt polypurine sequence ~ 175 nt upstream from the polyadenylation sites was found to also be necessary for the enhanced expression. We conclude that the use of Ext terminator has great potential to benefit the production of recombinant proteins in plants.
Collapse
Affiliation(s)
- Sun Hee Rosenthal
- The Biodesign Institute, Center for Immunotherapy, Vaccines, and Virotherapy, School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA
| | - Andrew G Diamos
- The Biodesign Institute, Center for Immunotherapy, Vaccines, and Virotherapy, School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA
| | - Hugh S Mason
- The Biodesign Institute, Center for Immunotherapy, Vaccines, and Virotherapy, School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA.
| |
Collapse
|
5
|
Ataie Kachoie E, Behjatnia SAA, Kharazmi S. Expression of Human Immunodeficiency Virus type 1 (HIV-1) coat protein genes in plants using cotton leaf curl Multan betasatellite-based vector. PLoS One 2018; 13:e0190403. [PMID: 29304063 PMCID: PMC5755781 DOI: 10.1371/journal.pone.0190403] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 12/14/2017] [Indexed: 12/31/2022] Open
Abstract
It has already been demonstrated that a betasatellite associated with cotton leaf curl Multan virus (CLCuMB) can be used as a plant and animal gene delivery vector to plants. To examine the ability of CLCuMB as a tool to transfer coat protein genes of HIV-1 to plants, two recombinant CLCuMB constructs in which the CLCuMB βC1 ORF was replaced with two HIV-1 genes fractions including a 696 bp DNA fragment related to the HIV-1 p24 gene and a 1501 bp DNA fragment related to the HIV-1 gag gene were constructed. Gag is the HIV-1 coat protein gene and p24 is a component of the particle capsid. Gag and p24 are used for vaccine production. Recombinant constructs were inoculated to Nicotiana glutinosa and N. benthamiana plants in the presence of an Iranian isolate of Tomato yellow leaf curl virus (TYLCV-[Ab]) as a helper virus. PCR analysis of inoculated plants indicated that p24 gene was successfully replicated in inoculated plants, but the gag gene was not. Real-time PCR and ELISA analysis of N. glutinosa and N. benthamiana plants containing the replicative forms of recombinant construct of CLCuMB/p24 indicated that p24 was expressed in these plants. This CLCuMB-based expression system offers the possibility of mass production of recombinant HIV-1 p24 protein in plants.
Collapse
Affiliation(s)
| | | | - Sara Kharazmi
- Institute of Biotechnology, Shiraz University, Shiraz, Iran
| |
Collapse
|
6
|
Hu SF, Huang YH, Lin CP, Liu LYD, Hong SF, Yang CY, Lo HF, Tseng TY, Chen WY, Lin SS. Development of a Mild Viral Expression System for Gain-Of-Function Study of Phytoplasma Effector In Planta. PLoS One 2015; 10:e0130139. [PMID: 26076458 PMCID: PMC4468105 DOI: 10.1371/journal.pone.0130139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 05/18/2015] [Indexed: 11/19/2022] Open
Abstract
PHYL1 and SAP54 are orthologs of pathogenic effectors of Aster yellow witches'-broom (AYWB) phytoplasma and Peanut witches'-broom (PnWB) phytoplasma, respectively. These effectors cause virescence and phyllody symptoms (hereafter leafy flower) in phytoplasma-infected plants. T0 lines of transgenic Arabidopsis expressing the PHYL1 or SAP54 genes (PHYL1 or SAP54 plants) show a leafy flower phenotype and result in seedless, suggesting that PHYL1 and SAP54 interfere with reproduction stage that restrict gain-of-function studies in the next generation of transgenic plants. Turnip mosaic virus (TuMV) mild strain (TuGK) has an Arg182Lys mutation in the helper-component proteinase (HC-ProR182K) that blocks suppression of the miRNA pathway and prevents symptom development in TuGK-infected plants. We exploited TuGK as a viral vector for gain-of-function studies of PHYL1 and SAP54 in Arabidopsis plants. TuGK-PHYL1- and TuGK-SAP54-infected Arabidopsis plants produced identical leafy flower phenotypes and similar gene expression profiles as PHYL1 and SAP54 plants. In addition, the leafy flower formation rate was enhanced in TuGK-PHYL1- or TuGK-SAP54-infected Arabidopsis plants that compared with the T0 lines of PHYL1 plants. These results provide more evidence and novel directions for further studying the mechanism of PHYL1/SAP54-mediated leafy flower development. In addition, the TuGK vector is a good alternative in transgenic plant approaches for rapid gene expression in gain-of-function studies.
Collapse
Affiliation(s)
- Sin-Fen Hu
- Institute of Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Yu-Hsin Huang
- Departement of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Chan-Pin Lin
- Departement of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Li-Yu Daisy Liu
- Department of Agronomy, National Taiwan University, Taipei, Taiwan
| | - Syuan-Fei Hong
- Department of Horticulture and Landscape Architecture, National Taiwan University, Taipei, Taiwan
| | - Chiao-Yin Yang
- Departement of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Hsiao-Feng Lo
- Department of Horticulture and Landscape Architecture, National Taiwan University, Taipei, Taiwan
| | - Ting-Yu Tseng
- Joint Center for Instruments and Researches, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan
| | - Wei-Yao Chen
- Institute of Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Shih-Shun Lin
- Institute of Biotechnology, National Taiwan University, Taipei, Taiwan
- Genome and Systems Biology Degree Program, National Taiwan University, Taipei, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
- * E-mail:
| |
Collapse
|
7
|
Sindarovska YR, Golovach IS, Belokurova VB, Gerasymenko IM, Sheludko YV, Kuchuk NV. Screening of plant cell culture collection for efficient host species for Agrobacterium-mediated transient expression. CYTOL GENET+ 2014. [DOI: 10.3103/s0095452714040070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
8
|
Skarjinskaia M, Ruby K, Araujo A, Taylor K, Gopalasamy-Raju V, Musiychuk K, Chichester JA, Palmer GA, de la Rosa P, Mett V, Ugulava N, Streatfield SJ, Yusibov V. Hairy Roots as a Vaccine Production and Delivery System. BIOTECHNOLOGY OF HAIRY ROOT SYSTEMS 2013; 134:115-34. [DOI: 10.1007/10_2013_184] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
9
|
Larsen JS, Curtis WR. RNA viral vectors for improved Agrobacterium-mediated transient expression of heterologous proteins in Nicotiana benthamiana cell suspensions and hairy roots. BMC Biotechnol 2012; 12:21. [PMID: 22559055 PMCID: PMC3403893 DOI: 10.1186/1472-6750-12-21] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 05/06/2012] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Plant cell suspensions and hairy root cultures represent scalable protein expression platforms. Low protein product titers have thus far limited the application of transient protein expression in these hosts. The objective of this work was to overcome this limitation by harnessing A. tumefaciens to deliver replicating and non-replicating RNA viral vectors in plant tissue co-cultures. RESULTS Replicating vectors derived from Potato virus X (PVX) and Tobacco rattle virus (TRV) were modified to contain the reporter gene β-glucuronidase (GUS) with a plant intron to prevent bacterial expression. In cell suspensions, a minimal PVX vector retaining only the viral RNA polymerase gene yielded 6.6-fold more GUS than an analogous full-length PVX vector. Transient co-expression of the minimal PVX vector with P19 of Tomato bushy stunt virus or HC-Pro of Tobacco etch virus to suppress post-transcriptional gene silencing increased GUS expression by 44 and 83%, respectively. A non-replicating vector containing a leader sequence from Cowpea mosaic virus (CPMV-HT) modified for enhanced translation led to 70% higher transient GUS expression than a control treatment. In hairy roots, a TRV vector capable of systemic movement increased GUS accumulation by 150-fold relative to the analogous PVX vector. Histochemical staining for GUS in TRV-infected hairy roots revealed the capacity for achieving even higher productivity per unit biomass. CONCLUSIONS For the first time, replicating PVX vectors and a non-replicating CPMV-HT vector were successfully applied toward transient heterologous protein expression in cell suspensions. A replicating TRV vector achieved transient GUS expression levels in hairy roots more than an order of magnitude higher than the highest level previously reported with a viral vector delivered by A. tumefaciens.
Collapse
Affiliation(s)
- Jeffrey S Larsen
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA
| | - Wayne R Curtis
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA
| |
Collapse
|
10
|
Rybicki EP, Martin DP. Virus-derived ssDNA vectors for the expression of foreign proteins in plants. Curr Top Microbiol Immunol 2011; 375:19-45. [PMID: 22038412 DOI: 10.1007/82_2011_185] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Plant viruses with ssRNA genomes provide a unique opportunity for generating expression vehicles for biopharming in plants, as constructs containing only the replication origin, with the replication-associated protein (Rep) gene provided in cis or in trans, can be replicationally amplified in vivo by several orders of magnitude, with significant accompanying increases in transcription and expression of gene(s) of interest. Appropriate replicating vectors or replicons may be derived from several different generic geminiviruses (family Geminiviridae) or nanoviruses (family Nanoviridae), for potential expression of a wide range of single or even multiple products in a wide range of plant families. The use of vacuum or other infiltration of whole plants by Agrobacterium tumefaciens suspensions has allowed the development of a set of expression vectors that rival the deconstructed RNA virus vectors in their yield and application, with some potential advantages over the latter that still need to be explored. Several modern applications of ssDNA plant vectors and their future potential will be discussed.
Collapse
Affiliation(s)
- Edward P Rybicki
- Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa,
| | | |
Collapse
|
11
|
Boivin EB, Lepage É, Matton DP, De Crescenzo G, Jolicoeur M. Transient expression of antibodies in suspension plant cell suspension cultures is enhanced when co-transformed with the tomato bushy stunt virus p19 viral suppressor of gene silencing. Biotechnol Prog 2010; 26:1534-43. [DOI: 10.1002/btpr.485] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
12
|
Franconi R, Demurtas OC, Massa S. Plant-derived vaccines and other therapeutics produced in contained systems. Expert Rev Vaccines 2010; 9:877-92. [PMID: 20673011 DOI: 10.1586/erv.10.91] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
The use of contained plant systems for the production of biopharmaceuticals represents a powerful alternative to current methods, combining the benefits of whole-plant systems and cell cultures. In vitro contained production systems include plant cell suspensions, hairy root cultures, novel plants grown in contained conditions and microalgae. These systems show intrinsic advantages, such as control over growth conditions, production in compliance with good manufacturing practice and avoidance of political resistance to the release of genetically modified field crops. At present, one of the two plant-produced vaccine-related products that have gone all the way through production and regulatory hurdles derives from tobacco cell suspensions, and the second is a human therapeutic enzyme, which is expected to reach commercial development soon and derives from carrot suspension cells. In the future, several other products from contained systems are expected to reach the clinical trial stage.
Collapse
Affiliation(s)
- Rosella Franconi
- Italian National Agency for New Technologies, UTBIORAD, CR Casaccia, Rome, Italy.
| | | | | |
Collapse
|
13
|
Regnard GL, Halley-Stott RP, Tanzer FL, Hitzeroth II, Rybicki EP. High level protein expression in plants through the use of a novel autonomously replicating geminivirus shuttle vector. PLANT BIOTECHNOLOGY JOURNAL 2010; 8:38-46. [PMID: 19929900 DOI: 10.1111/j.1467-7652.2009.00462.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We constructed a novel autonomously replicating gene expression shuttle vector, with the aim of developing a system for transiently expressing proteins at levels useful for commercial production of vaccines and other proteins in plants. The vector, pRIC, is based on the mild strain of the geminivirus Bean yellow dwarf virus (BeYDV-m) and is replicationally released into plant cells from a recombinant Agrobacterium tumefaciens Ti plasmid. pRIC differs from most other geminivirus-based vectors in that the BeYDV replication-associated elements were included in cis rather than from a co-transfected plasmid, while the BeYDV capsid protein (CP) and movement protein (MP) genes were replaced by an antigen encoding transgene expression cassette derived from the non-replicating A. tumefaciens vector, pTRAc. We tested vector efficacy in Nicotiana benthamiana by comparing transient cytoplasmic expression between pRIC and pTRAc constructs encoding either enhanced green fluorescent protein (EGFP) or the subunit vaccine antigens, human papillomavirus subtype 16 (HPV-16) major CP L1 and human immunodeficiency virus subtype C p24 antigen. The pRIC constructs were amplified in planta by up to two orders of magnitude by replication, while 50% more HPV-16 L1 and three- to seven-fold more EGFP and HIV-1 p24 were expressed from pRIC than from pTRAc. Vector replication was shown to be correlated with increased protein expression. We anticipate that this new high-yielding plant expression vector will contribute towards the development of a viable plant production platform for vaccine candidates and other pharmaceuticals.
Collapse
Affiliation(s)
- Guy L Regnard
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Observatory, South Africa
| | | | | | | | | |
Collapse
|
14
|
O'Neill KM, Larsen JS, Curtis WR. Scale-up of Agrobacterium-mediated transient protein expression in bioreactor-grown Nicotiana glutinosa plant cell suspension culture. Biotechnol Prog 2008; 24:372-6. [PMID: 18335952 DOI: 10.1021/bp0703127] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reporter gene beta-glucuronidase was transiently expressed in a 51-L bioreactor-grown plant cell suspension culture of Nicotiana glutinosa at a yield of approximately 1.1 mg through co-culture with an auxotrophic strain of Agrobacterium tumefaciens. The three order of magnitude scale-up involved the investigation of factors contributing to transient expression including the timing of Agrobacterium inoculation relative to the plant cell growth phase, plant tissue culture hormonal triggers and plant cell cycle synchronization. The co-culture process was simplified to facilitate implementation in a pilot-scale bioreactor. At the shake flask scale it was determined that elevated concentrations of oxygen in the headspace were detrimental to transient expression levels and the addition of acetosyringone to the co-culture had a negligible effect. The bacterial preparation process was also streamlined, permitting the direct transfer of the Agrobacterium culture from a bench-scale fermentor to the pilot-scale plant cell culture bioreactor. Increasing expression levels and overcoming batch-to-batch variability despite extensive procedure systemization remain the major technical hurdles.
Collapse
Affiliation(s)
- Kristin M O'Neill
- Department of Chemical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | | | | |
Collapse
|