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Improved Production of Aspergillus usamii endo-β-1,4-Xylanase in Pichia pastoris via Combined Strategies. BIOMED RESEARCH INTERNATIONAL 2016; 2016:3265895. [PMID: 27066499 PMCID: PMC4811622 DOI: 10.1155/2016/3265895] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 01/24/2016] [Indexed: 11/24/2022]
Abstract
A series of strategies were applied to improve expression level of recombinant endo-β-1,4-xylanase from Aspergillus usamii (A. usamii) in Pichia pastoris (P. pastoris). Firstly, the endo-β-1,4-xylanase (xynB) gene from A. usamii was optimized for P. pastoris and expressed in P. pastoris. The maximum xylanase activity of optimized (xynB-opt) gene was 33500 U/mL after methanol induction for 144 h in 50 L bioreactor, which was 59% higher than that by wild-type (xynB) gene. To further increase the expression of xynB-opt, the Vitreoscilla hemoglobin (VHb) gene was transformed to the recombinant strain containing xynB-opt. The results showed that recombinant strain harboring the xynB-opt and VHb (named X33/xynB-opt-VHb) displayed higher biomass, cell viability, and xylanase activity. The maximum xylanase activity of X33/xynB-opt-VHb in 50 L bioreactor was 45225 U/mL, which was 35% and 115% higher than that by optimized (xynB-opt) gene and wild-type (xynB) gene. Finally, the induction temperature of X33/xynB-opt-VHb was optimized in 50 L bioreactor. The maximum xylanase activity of X33/xynB-opt-VHb reached 58792 U/mL when the induction temperature was 22°C. The results presented here will greatly contribute to improving the production of recombinant proteins in P. pastoris.
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Recent applications of Vitreoscilla hemoglobin technology in bioproduct synthesis and bioremediation. Appl Microbiol Biotechnol 2015; 99:1627-36. [PMID: 25575886 DOI: 10.1007/s00253-014-6350-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 12/19/2014] [Accepted: 12/21/2014] [Indexed: 10/24/2022]
Abstract
Since its first use in 1990 to enhance production of α-amylase in E. coli, engineering of heterologous hosts to express the hemoglobin from the bacterium Vitreoscilla (VHb) has become a widely used strategy to enhance production of a variety of bioproducts, stimulate bioremediation, and increase growth and survival of engineered organisms. The hosts have included a variety of bacteria, yeast, fungi, higher plants, and even animals. The beneficial effects of VHb expression are presumably the result of one or more of its activities. The available evidence indicates that these include oxygen binding and delivery to the respiratory chain and oxygenases, protection against reactive oxygen species, and control of gene expression. In the past 4 to 5 years, the use of this "VHb technology" has continued in a variety of biotechnological applications in a wide range of organisms. These include enhancement of production of an ever wider array of bioproducts, new applications in bioremediation, a possible role in enhancing aerobic waste water treatment, and the potential to enhance growth and survival of both plants and animals of economic importance.
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Akbas MY, Sar T, Ozcelik B. Improved ethanol production from cheese whey, whey powder, and sugar beet molasses by "Vitreoscilla hemoglobin expressing" Escherichia coli. Biosci Biotechnol Biochem 2014; 78:687-94. [PMID: 25036968 DOI: 10.1080/09168451.2014.896734] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
This work investigated the improvement of ethanol production by engineered ethanologenic Escherichia coli to express the hemoglobin from the bacterium Vitreoscilla (VHb). Ethanologenic E. coli strain FBR5 and FBR5 transformed with the VHb gene in two constructs (strains TS3 and TS4) were grown in cheese whey (CW) medium at small and large scales, at both high and low aeration, or with whey powder (WP) or sugar beet molasses hydrolysate (SBMH) media at large scale and low aeration. Culture pH, cell growth, VHb levels, and ethanol production were evaluated after 48 h. VHb expression in TS3 and TS4 enhanced their ethanol production in CW (21-419%), in WP (17-362%), or in SBMH (48-118%) media. This work extends the findings that "VHb technology" may be useful for improving the production of ethanol from waste and byproducts of various sources.
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Affiliation(s)
- Meltem Yesilcimen Akbas
- a Department of Molecular Biology and Genetics , Gebze Institute of Technology , Gebze , Turkey
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Shah P, Chiu FS, Lan JCW. Aerobic utilization of crude glycerol by recombinant Escherichia coli for simultaneous production of poly 3-hydroxybutyrate and bioethanol. J Biosci Bioeng 2013; 117:343-50. [PMID: 24140105 DOI: 10.1016/j.jbiosc.2013.08.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 08/27/2013] [Accepted: 08/30/2013] [Indexed: 11/29/2022]
Abstract
Crude glycerol, an inevitable byproduct during biodiesel production, is emerging as a potential feedstock for fermentation, due to its availability and a reasonable price. Biological utilization of abundant crude glycerol to several value added products is contemporary research area with beneficial features. Solving the problem of proper disposal and raising economic viability of biodiesel industries. Several researches have been directed toward the production of numerous products by using Escherichia coli, an ideal organism for heterologous expression of various foreign proteins. In this fashion, recombinant E. coli strains were constructed for the simultaneous production of poly 3-hydroxybutyrate (P3HB) and bioethanol from crude glycerol. The incorporation of aldehyde reductase (Alrd) and aldehyde dehydrogenase (AldH) in recombinant strain showed 2-fold increment in crude glycerol utilization under aerobic condition. Moreover, these two enzymes introduced an alternative pathway leading toward the potential production of bioethanol which was more than redox-balancing steps. Acetate was accumulated as an intermediate product. Subsequently, acetate was utilized as substrate in the second pathway, which directly converted acetyl-CoA to P3HB. This strategy demonstrated a potential production manner of bioethanol as an extracellular product and P3HB as water insoluble inclusion bodies inside E. coli. The maximum production of bioethanol and P3HB in the recombinant strain was 0.8 g L(-1) (17.4 mmol L(-1)) and 30.2% (w/w dry cell weight), respectively, which were higher than the parental strain.
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Affiliation(s)
- Pramod Shah
- Graduate School of Biotechnology and Bioengineering, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 320, Taiwan
| | - Feng-Shen Chiu
- Graduate School of Biotechnology and Bioengineering, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 320, Taiwan
| | - John Chi-Wei Lan
- Graduate School of Biotechnology and Bioengineering, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 320, Taiwan; Bio-refinery and Bioprocess Engineering Laboratory, Department of Chemical Engineering and Materials Science, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 320, Taiwan.
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Biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with co-expressed propionate permease (prpP), beta-ketothiolase B (bktB), and propionate-CoA synthase (prpE) in Escherichia coli. Biochem Eng J 2013. [DOI: 10.1016/j.bej.2012.12.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Stark BC, Dikshit KL, Pagilla KR. The Biochemistry of Vitreoscilla hemoglobin. Comput Struct Biotechnol J 2012; 3:e201210002. [PMID: 24688662 PMCID: PMC3962134 DOI: 10.5936/csbj.201210002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 09/17/2012] [Indexed: 01/17/2023] Open
Abstract
The hemoglobin (VHb) from Vitreoscilla was the first bacterial hemoglobin discovered. Its structure and function have been extensively investigated, and engineering of a wide variety of heterologous organisms to express VHb has been performed to increase their growth and productivity. This strategy has shown promise in applications as far-ranging as the production of antibiotics and petrochemical replacements by microorganisms to increasing stress tolerance in plants. These applications of “VHb technology” have generally been of the “black box” variety, wherein the endpoint studied is an increase in the levels of a certain product or improved growth and survival. Their eventual optimization, however, will require a thorough understanding of the various functions and activities of VHb, and how VHb expression ripples to affect metabolism more generally. Here we review the current knowledge of these topics. VHb's functions all involve oxygen binding (and often delivery) in one way or another. Several biochemical and structure-function studies have provided an insight into the molecular details of this binding and delivery. VHb activities are varied. They include supply of oxygen to oxygenases and the respiratory chain, particularly under low oxygen conditions; oxygen sensing and modulation of transcription factor activity; and detoxification of NO, and seem to require interactions of VHb with “partner proteins”. VHb expression affects the levels of ATP and NADH, although not enormously. VHb expression may affect the level of many compounds of intermediary metabolism, and, apparently, alters the levels of expression of many genes. Thus, the metabolic changes in organisms engineered to express VHb are likely to be numerous and complicated.
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Affiliation(s)
- Benjamin C Stark
- Biology Division, Department of Biological and Chemical Sciences, Illinois Institute of Technology, Chicago IL 60616, USA
| | - Kanak L Dikshit
- Institute of Microbial Technology, Sec-39a, Chandigarh, 160036, India
| | - Krishna R Pagilla
- Department of Civil and Architectural Engineering, Illinois Institute of Technology, Chicago IL 60616, USA
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Abanoz K, Stark B, Akbas M. Enhancement of ethanol production from potato-processing wastewater by engineering Escherichia coli
using Vitreoscilla
haemoglobin. Lett Appl Microbiol 2012; 55:436-43. [DOI: 10.1111/lam.12000] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 09/10/2012] [Accepted: 09/10/2012] [Indexed: 11/29/2022]
Affiliation(s)
- K. Abanoz
- Department of Molecular Biology and Genetics; Gebze Institute of Technology; Gebze-Kocaeli Turkey
| | - B.C. Stark
- Biology Division, Department of Biological and Chemical Sciences; Illinois Institute of Technology; Chicago IL USA
| | - M.Y. Akbas
- Department of Molecular Biology and Genetics; Gebze Institute of Technology; Gebze-Kocaeli Turkey
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Lower temperature cultures enlarge the effects of Vitreoscilla hemoglobin expression on recombinant Pichia pastoris. Int J Mol Sci 2012. [PMID: 23202948 PMCID: PMC3497322 DOI: 10.3390/ijms131013212] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
An heterologous expression of Vitreoscilla hemoglobin (VHb) for improving cell growth and recombinant protein production has been successfully demonstrated in various hosts, including Pichia pastoris. Lower temperature cultures can enhance target protein production in some studies of P. pastoris. In this study, the strategy of combining heterologous VHb expression and lower temperature cultures in P. pastoris showed that final cell density and viability of VHb+ strain at 23 °C were higher than that at 30 °C. In addition, the effects of VHb expression on recombinant β-galactosidase production and oxygen uptake rate were also higher at 23 °C than at 30 °C. Consequently, lower temperature cultures can enlarge VHb effectiveness on cell performance of P. pastoris. This is because VHb activity obtained at 23 °C cultures was twofold higher than that at 30 °C cultures, due to a different heme production. This strategy makes P. pastoris an excellent expression host particularly suitable for increasing the yields of the low-stability and aggregation-prone recombinant proteins.
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Wu JM, Fu WC. Intracellular co-expression of Vitreoscilla hemoglobin enhances cell performance and β-galactosidase production in Pichia pastoris. J Biosci Bioeng 2011; 113:332-7. [PMID: 22099376 DOI: 10.1016/j.jbiosc.2011.10.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 10/08/2011] [Accepted: 10/17/2011] [Indexed: 10/15/2022]
Abstract
Pichia pastoris has been used to produce various recombinant proteins under high oxygen demand conditions. To improve the heterologous production of β-galactosidase, the vgb gene encoding Vitreoscilla hemoglobin (VHb) was co-expressed in the P. pastoris cytoplasm under the control of the methanol-inducible promoter. Co-expression of VHb under different aeration conditions improved cell performance in terms of growth, viability, respiratory rate, and β-galactosidase production. Under limiting aeration conditions, the VHb(+) strain produced 28.2% more biomass but 31.2% less total β-galactosidase activity than the VHb(-) strain. Under non-limiting aeration conditions, the VHb(+) strain showed 20.3% higher cell growth and 9.9% more total β-galactosidase activity than the VHb(-) strain. Moreover, under these conditions, the VHb(+) strain was 7.7% more viable and had a 28.2% higher oxygen uptake rate (OUR) than the VHb(-) strain. Evidently, VHb can enhance the OUR and promote methanol metabolism, thereby improving cell performance and β-galactosidase production.
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Affiliation(s)
- Jyh-Ming Wu
- Department of Chemical and Materials Engineering, Chinese Culture University, 55 Hwa-Kang Road, Yang-Ming-Shan, Taipei 11114, Taiwan.
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Wang X, Sun Y, Shen X, Ke F, Zhao H, Liu Y, Xu L, Yan Y. Intracellular expression of Vitreoscilla hemoglobin improves production of Yarrowia lipolytica lipase LIP2 in a recombinant Pichia pastoris. Enzyme Microb Technol 2011; 50:22-8. [PMID: 22133436 DOI: 10.1016/j.enzmictec.2011.09.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 09/13/2011] [Accepted: 09/14/2011] [Indexed: 10/17/2022]
Abstract
The Yarrowia lipolytica lipase LIP2 (YlLIP2) gene lip2 and Vitreoscilla hemoglobin gene vgb were co-expressed in Pichia pastoris, both under the control of AOX1 promoter, in order to alleviate respiration limitation under conditions of high cell-density fermentation and enhance YlLIP2 production. The results showed that recombinant P. pastoris strains harboring the lip2 and vgb genes (VHb(+)) displayed higher biomass and YlLIP2 activity than control strains (VHb(-)). Compared with VHb(-) cells, the expression levels of YlLIP2 in VHb-expressing cells when oxygen was not a limiting factor were improved 31.5% in shake-flask culture and 22% in a 10-L fermentor. Under non-limiting dissolved oxygen (DO) conditions, the maximum YlLIP2 activity of VHb(+) in a 10-L fermentor reached 33,000 U/mL. Oxygen limitation had a more negative effect on YlLIP2 productivity in VHb(-) cells than in VHb(+) cells. The highest YlLIP2 activity of VHb(+) cells was approximately 1.84-fold higher than that of VHb(-) cells at lower DO levels. Moreover, the recombinant strain VHb(+) exhibited a higher specific oxygen uptake rate and achieved higher cell viability under oxygen limiting and non-limiting conditions compared with VHb(-) cells. Therefore, the above results suggest that intracellular expression of VHb in recombinant P. pastoris has the potential to improve cell growth and industrial enzyme production.
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Affiliation(s)
- Xiaofeng Wang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
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Stark BC, Dikshit KL, Pagilla KR. Recent advances in understanding the structure, function, and biotechnological usefulness of the hemoglobin from the bacterium Vitreoscilla. Biotechnol Lett 2011; 33:1705-14. [DOI: 10.1007/s10529-011-0621-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 04/08/2011] [Indexed: 11/24/2022]
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Guan B, Ma H, Wang Y, Hu Y, Lin Z, Zhu Z, Hu W. Vitreoscilla hemoglobin (VHb) overexpression increases hypoxia tolerance in zebrafish (Danio rerio). MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2011; 13:336-344. [PMID: 20694827 DOI: 10.1007/s10126-010-9305-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Accepted: 06/09/2010] [Indexed: 05/29/2023]
Abstract
Aquaculture farming may benefit from genetically engineering fish to tolerate environmental stress. Here, we used the vector pCVCG expressing the Vitreoscilla hemoglobin (vhb) gene driven by the common carp β-actin promoter to create stable transgenic zebrafish. The survival rate of the 7-day-old F(2) transgenic fish was significantly greater than that of the sibling controls under 2.5% O(2) (dissolved oxygen (DO), 0.91 mg/l). Meanwhile, we investigated the relative expression levels of several marker genes (hypoxia-inducible factor alpha 1, heat shock cognate 70-kDa protein, erythropoietin, beta and alpha globin genes, lactate dehydrogenase, catalase, superoxide dismutase, and glutathione peroxidase) of transgenic fish and siblings after hypoxia exposure for 156 h. The expression profiles of the vhb transgenic zebrafish revealed that VHb could partially alleviate the hypoxia stress response to improve the survival rate of the fish. These results suggest that that vhb gene may be an efficient candidate for genetically modifying hypoxia tolerance in fish.
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Affiliation(s)
- Bo Guan
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
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Horng YT, Chien CC, Wei YH, Chen SY, Lan JW, Sun YM, Soo PC. Functional cis-expression of phaCAB genes for poly(3-hydroxybutyrate) production by Escherichia coli. Lett Appl Microbiol 2011; 52:475-83. [DOI: 10.1111/j.1472-765x.2011.03029.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Enhanced Production of l-Arginine by Expression of Vitreoscilla Hemoglobin Using a Novel Expression System in Corynebacterium crenatum. Appl Biochem Biotechnol 2010; 163:707-19. [DOI: 10.1007/s12010-010-9076-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Accepted: 08/27/2010] [Indexed: 10/19/2022]
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Horng YT, Chang KC, Chien CC, Wei YH, Sun YM, Soo PC. Enhanced polyhydroxybutyrate (PHB) productionviathe coexpressedphaCABandvgbgenes controlled by arabinose PBADpromoter inEscherichia coli. Lett Appl Microbiol 2010; 50:158-67. [DOI: 10.1111/j.1472-765x.2009.02772.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Urgun-Demirtas M, Stark B, Pagilla K. Use of Genetically Engineered Microorganisms (GEMs) for the Bioremediation of Contaminants. Crit Rev Biotechnol 2008; 26:145-64. [PMID: 16923532 DOI: 10.1080/07388550600842794] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This paper presents a critical review of the literature on the application of genetically engineered microorganisms (GEMs) in bioremediation. The important aspects of using GEMs in bioremediation, such as development of novel strains with desirable properties through pathway construction and the modification of enzyme specificity and affinity, are discussed in detail. Particular attention is given to the genetic engineering of bacteria using bacterial hemoglobin (VHb) for the treatment of aromatic organic compounds under hypoxic conditions. The application of VHb technology may advance treatment of contaminated sites, where oxygen availability limits the growth of aerobic bioremediating bacteria, as well as the functioning of oxygenases required for mineralization of many organic pollutants. Despite the many advantages of GEMs, there are still concerns that their introduction into polluted sites to enhance bioremediation may have adverse environmental effects, such as gene transfer. The extent of horizontal gene transfer from GEMs in the environment, compared to that of native organisms including benefits regarding bacterial bioremediation that may occur as a result of such transfer, is discussed. Recent advances in tracking methods and containment strategies for GEMs, including several biological systems that have been developed to detect the fate of GEMs in the environment, are also summarized in this review. Critical research questions pertaining to the development and implementation of GEMs for enhanced bioremediation have been identified and posed for possible future research.
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Affiliation(s)
- Meltem Urgun-Demirtas
- Department of Chemical and Environmental Engineering, Illinois Institute of Technology, Chicago, 60616, USA
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Chen H, Chu J, Zhang S, Zhuang Y, Qian J, Wang Y, Hu X. Intracellular expression of Vitreoscilla hemoglobin improves S-adenosylmethionine production in a recombinant Pichia pastoris. Appl Microbiol Biotechnol 2007; 74:1205-12. [PMID: 17334759 DOI: 10.1007/s00253-006-0705-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2006] [Revised: 09/19/2006] [Accepted: 09/21/2006] [Indexed: 10/23/2022]
Abstract
To develop an efficient way to produce S-adenosylmethionine (SAM), methionine adenosyltransferase gene (mat) from Streptomyces spectabilis and Vitreoscilla hemoglobin gene (vgb) were coexpressed intracellularly in Pichia pastoris, both under control of methanol-inducible promoter. Expression of mat in P. pastoris resulted in about 27 times higher specific activity of methionine adenosyltransferase (SMAT) and about 19 times higher SAM production relative to their respective control, suggesting that overexpression of mat could be used as an efficient method for constructing SAM-accumulating strain. Under induction concentration of 0.8 and 2.4% methanol, coexpression of vgb improved, though to different extent, cell growth, SAM production, and respiratory rate. However, the effects of VHb on SAM content (specific yield of SAM production) and SMAT seemed to be methanol concentration-dependent. When cells were induced with 0.8% methanol, no significant effects of VHb expression on SAM content and specific SMAT could be detected. When the cells were induced with 2.4% methanol, vgb expression increased SAM content significantly and depressed SMAT remarkably. We suggested that under our experimental scheme, the presence of VHb might improve ATP synthesis rate and thus improve cell growth and SAM production in the recombinant P. pastoris.
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Affiliation(s)
- Huaxin Chen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 200237 Shanghai, People's Republic of China
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Zhang L, Li Y, Wang Z, Xia Y, Chen W, Tang K. Recent developments and future prospects of Vitreoscilla hemoglobin application in metabolic engineering. Biotechnol Adv 2007; 25:123-36. [PMID: 17184955 DOI: 10.1016/j.biotechadv.2006.11.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Revised: 11/02/2006] [Accepted: 11/02/2006] [Indexed: 11/27/2022]
Abstract
In hypoxic conditions, bacteria express a kind of hemoglobin, which is proposed to enhance respiration and energy metabolism by promoting oxygen delivery. Bacteria hemoglobin from Vitreoscilla stercoraria - Vitreoscilla hemoglobin (VHb), when expressed in various hosts in oxygen-limited conditions, has been shown to improve growth, protein secretion, metabolite productivity and stress resistance of hosts, thus rendering the protein promising in metabolic engineering, especially in plant metabolism optimization. In this review, many well-studies areas are presented to illustrate the potential of VHb application in biotechnology industry, to discuss the cellular mechanisms of VHb function and to show the wide variety of approaches taken within the field.
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Affiliation(s)
- Lei Zhang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan-SJTU-Nottingham Plant Biotechnology R and D Center, Fudan University, Shanghai 200433, PR China
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Dogan I, Pagilla KR, Webster DA, Stark BC. Expression of Vitreoscilla hemoglobin in Gordonia amarae enhances biosurfactant production. J Ind Microbiol Biotechnol 2006; 33:693-700. [PMID: 16491354 DOI: 10.1007/s10295-006-0097-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Accepted: 01/29/2006] [Indexed: 11/28/2022]
Abstract
The gene (vgb) encoding Vitreoscilla (bacterial) hemoglobin (VHb) was electroporated into Gordonia amarae, where it was stably maintained, and expressed at about 4 nmol VHb g(-1) of cells. The maximum cell mass (OD(600)) of vgb-bearing G. amarae was greater than that of untransformed G. amarae for a variety of media and aeration conditions (2.8-fold under normal aeration and 3.4-fold under limited aeration in rich medium, and 3.5-fold under normal aeration and 3.2-fold under limited aeration in mineral salts medium). The maximum level of trehalose lipid from cultures grown in rich medium plus hexadecane was also increased for the recombinant strain, by 4.0-fold in broth and 1.8-fold in cells under normal aeration and 2.1-fold in broth and 1.4-fold in cells under limited aeration. Maximum overall biosurfactant production was also increased in the engineered strain, by 1.4-fold and 2.4-fold for limited and normal aeration, respectively. The engineered strain may be an improved source for producing purified biosurfactant or an aid to microorganisms bioremediating sparingly soluble contaminants in situ.
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Affiliation(s)
- Ilhan Dogan
- Biology Division, Department of Biological, Chemical, and Physical Sciences, Illinois Institute of Technology, IIT Center, Chicago, IL 60616, USA
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Urgun-Demirtas M, Stark B, Pagilla K. 2-Chlorobenzoate biodegradation by recombinant Burkholderia cepacia under hypoxic conditions in a membrane bioreactor. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2005; 77:511-8. [PMID: 16274085 DOI: 10.2175/106143005x67421] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The feasibility of applying bacterial hemoglobin technology to degrade 2-chlorobenzoate (2-CBA) through co-metabolism under hypoxic conditions in a membrane bioreactor (MBR) process has been studied in the laboratory. 2-chlorobenzoate removal and chloride release rates in the MBR system varied from 99 to 78% and 98 to 73%, respectively, depending on the operation conditions. Chemical oxygen demand (COD) removal efficiencies were more than 90% at food-to-microorganism ratios ranging from 0.32 to 0.62 g/g/d, and the observed yield was 0.13 to 0.20 g biomass/g COD. The bacterial cell-floc size-distribution analysis showed that there is a significant change in bacterial floc size due to high shear stress during operation of the MBR. To characterize growth kinetics of Burkholderia cepacia strain dinitrotoluene, a mathematical model that describes co-metabolic oxidation of 2-CBA in an MBR has been developed.
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Affiliation(s)
- Meltem Urgun-Demirtas
- Department of Chemical and Environmental Engineering, Illinois Institute of Technology, Chicago 60616, USA
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