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Bayon-Vicente G, Wattiez R, Leroy B. Global Proteomic Analysis Reveals High Light Intensity Adaptation Strategies and Polyhydroxyalkanoate Production in Rhodospirillum rubrum Cultivated With Acetate as Carbon Source. Front Microbiol 2020; 11:464. [PMID: 32269553 PMCID: PMC7109303 DOI: 10.3389/fmicb.2020.00464] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 03/04/2020] [Indexed: 11/25/2022] Open
Abstract
Purple non-sulfur bacteria (PNSBs) are well known for their metabolic versatility. Among them, Rhodospirillum rubrum can assimilate a broad range of carbon sources, including volatile fatty acids (VFAs), such as acetate, propionate or butyrate. These carbon sources are gaining increasing interest in bioindustrial processes since they allow reduction of the production costs. Recently, our lab discovered that, after long term cultivation with acetate as unique carbon source, Rs. rubrum got acclimated to this carbon source which resulted in a drastic reduction of the lag phase. This acclimation was characterized by the amplification of the genomic region containing, among others, genes belonging to the ethylmalonyl-CoA (EMC) pathway, which has been demonstrated to be required for acetate assimilation in Rs. rubrum. In this paper, we combined bacterial growth analysis with proteomic (SWATH -Sequential Windowed Acquisition of All Theoretical Fragment Ion Mass Spectra-processing) investigation to better understand the bacterial response to a sudden increase of the light intensity. We compared the impact of suddenly increasing light intensity on the WT strain to that on the newly described acetate-competent strain in the presence of acetate. Contrary to what was observed with the WT strain, we observed that the acetate-competent strain was tolerant to the light stress. Proteomic analysis revealed that increasing light intensity had a significant impact on the photosynthetic apparatus, especially in the wild-type strain cultivated in the presence of acetate and low concentration of HCO3–. This phenomenon was accompanied by a relatively higher abundance of certain stress related proteins. Our results suggested that the production of PHA, but also potentially of branched chain amino acids synthesis, could be part of the mechanism used by Rs. rubrum to adapt to the light stress and the redox imbalance it triggered.
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Affiliation(s)
- Guillaume Bayon-Vicente
- Laboratory of Proteomics and Microbiology, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Ruddy Wattiez
- Laboratory of Proteomics and Microbiology, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Baptiste Leroy
- Laboratory of Proteomics and Microbiology, Research Institute for Biosciences, University of Mons, Mons, Belgium
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Reprogramming Halomonas for industrial production of chemicals. J Ind Microbiol Biotechnol 2018; 45:545-554. [PMID: 29948194 DOI: 10.1007/s10295-018-2055-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 05/31/2018] [Indexed: 12/26/2022]
Abstract
Halomonas spp. are able to grow under a high salt concentration at alkali pH, they are able to resist contamination by other microbes. Development of Halomonas spp. as platform production strains for the next-generation industrial biotechnology (NGIB) is intensively studied. Among Halomonas spp., Halomonas bluephagenesis is the best studied one with available engineering tools and methods to reprogram it for production of various polyhydroxyalkanoates, proteins, and chemicals. Due to its contamination resistance, H. bluephagenesis can be grown under open and continuous processes not just in the labs but also in at least 1000 L fermentor scale. It is expected that NGIB based on Halomonas spp. be able to engineer for production of increasing number of products in a competitive manner.
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Kutralam-Muniasamy G, Perez-Guevara F. Recombinant surface engineering to enhance and expand the potential of biologically produced nanoparticles: A review. Process Biochem 2017. [DOI: 10.1016/j.procbio.2016.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Zhou M, Li Q, Wang R. Current Experimental Methods for Characterizing Protein-Protein Interactions. ChemMedChem 2016; 11:738-56. [PMID: 26864455 PMCID: PMC7162211 DOI: 10.1002/cmdc.201500495] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 01/08/2016] [Indexed: 12/14/2022]
Abstract
Protein molecules often interact with other partner protein molecules in order to execute their vital functions in living organisms. Characterization of protein-protein interactions thus plays a central role in understanding the molecular mechanism of relevant protein molecules, elucidating the cellular processes and pathways relevant to health or disease for drug discovery, and charting large-scale interaction networks in systems biology research. A whole spectrum of methods, based on biophysical, biochemical, or genetic principles, have been developed to detect the time, space, and functional relevance of protein-protein interactions at various degrees of affinity and specificity. This article presents an overview of these experimental methods, outlining the principles, strengths and limitations, and recent developments of each type of method.
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Affiliation(s)
- Mi Zhou
- State Key Laboratory of Bioorganic & Natural Products Chemistry, Collaborative Innovation Center of Chemistry for Life Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Rd, Shanghai, 200032, People's Republic of China
| | - Qing Li
- State Key Laboratory of Bioorganic & Natural Products Chemistry, Collaborative Innovation Center of Chemistry for Life Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Rd, Shanghai, 200032, People's Republic of China
| | - Renxiao Wang
- State Key Laboratory of Bioorganic & Natural Products Chemistry, Collaborative Innovation Center of Chemistry for Life Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Rd, Shanghai, 200032, People's Republic of China.
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Macau, 999078, People's Republic of China.
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Zhou M, Li Q, Wang R. Current Experimental Methods for Characterizing Protein-Protein Interactions. ChemMedChem 2016. [PMID: 26864455 DOI: 10.1002/cmdc.201500495.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Protein molecules often interact with other partner protein molecules in order to execute their vital functions in living organisms. Characterization of protein-protein interactions thus plays a central role in understanding the molecular mechanism of relevant protein molecules, elucidating the cellular processes and pathways relevant to health or disease for drug discovery, and charting large-scale interaction networks in systems biology research. A whole spectrum of methods, based on biophysical, biochemical, or genetic principles, have been developed to detect the time, space, and functional relevance of protein-protein interactions at various degrees of affinity and specificity. This article presents an overview of these experimental methods, outlining the principles, strengths and limitations, and recent developments of each type of method.
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Affiliation(s)
- Mi Zhou
- State Key Laboratory of Bioorganic & Natural Products Chemistry, Collaborative Innovation Center of Chemistry for Life Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Rd, Shanghai, 200032, People's Republic of China
| | - Qing Li
- State Key Laboratory of Bioorganic & Natural Products Chemistry, Collaborative Innovation Center of Chemistry for Life Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Rd, Shanghai, 200032, People's Republic of China
| | - Renxiao Wang
- State Key Laboratory of Bioorganic & Natural Products Chemistry, Collaborative Innovation Center of Chemistry for Life Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Rd, Shanghai, 200032, People's Republic of China. .,State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Macau, 999078, People's Republic of China.
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Ma HK, Liu MM, Li SY, Wu Q, Chen JC, Chen GQ. Application of polyhydroxyalkanoate (PHA) synthesis regulatory protein PhaR as a bio-surfactant and bactericidal agent. J Biotechnol 2013; 166:34-41. [DOI: 10.1016/j.jbiotec.2013.04.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Revised: 04/18/2013] [Accepted: 04/26/2013] [Indexed: 01/28/2023]
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Yamada M, Takahashi S, Okahata Y, Doi Y, Numata K. Monitoring and kinetic analysis of the molecular interactions by which a repressor protein, PhaR, binds to target DNAs and poly[(R)-3-hydroxybutyrate]. AMB Express 2013; 3:6. [PMID: 23351303 PMCID: PMC3570403 DOI: 10.1186/2191-0855-3-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Accepted: 01/22/2013] [Indexed: 11/10/2022] Open
Abstract
The repressor protein PhaR, which is a component of poly[(R)-3-hydroxybutyrate] granules, functions as a repressor of the gene expression of the phasin PhaP and of PhaR itself. We used a quartz crystal microbalance to investigate the binding behavior by which PhaR in Ralstonia eutropha H16 targets DNAs and amorphous poly[(R)-3-hydroxybutyrate] thin films. Binding rate constants, dissociation rate constants, and dissociation constants of the binding of PhaR to DNA and to amorphous poly[(R)-3-hydroxybutyrate] suggested that PhaR bind to both in a similar manner. On the basis of the binding rate constant values, we proposed that the phaP gene would be derepressed in harmony with the ratio of the concentration of the target DNA to the concentration of amorphous poly[(R)-3-hydroxybutyrate] at the start of poly[(R)-3-hydroxybutyrate] synthesis in R. eutropha H16.
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Diversity in genetic in vivo methods for protein-protein interaction studies: from the yeast two-hybrid system to the mammalian split-luciferase system. Microbiol Mol Biol Rev 2012; 76:331-82. [PMID: 22688816 DOI: 10.1128/mmbr.05021-11] [Citation(s) in RCA: 134] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The yeast two-hybrid system pioneered the field of in vivo protein-protein interaction methods and undisputedly gave rise to a palette of ingenious techniques that are constantly pushing further the limits of the original method. Sensitivity and selectivity have improved because of various technical tricks and experimental designs. Here we present an exhaustive overview of the genetic approaches available to study in vivo binary protein interactions, based on two-hybrid and protein fragment complementation assays. These methods have been engineered and employed successfully in microorganisms such as Saccharomyces cerevisiae and Escherichia coli, but also in higher eukaryotes. From single binary pairwise interactions to whole-genome interactome mapping, the self-reassembly concept has been employed widely. Innovative studies report the use of proteins such as ubiquitin, dihydrofolate reductase, and adenylate cyclase as reconstituted reporters. Protein fragment complementation assays have extended the possibilities in protein-protein interaction studies, with technologies that enable spatial and temporal analyses of protein complexes. In addition, one-hybrid and three-hybrid systems have broadened the types of interactions that can be studied and the findings that can be obtained. Applications of these technologies are discussed, together with the advantages and limitations of the available assays.
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Gao X, Yuan XX, Shi ZY, Guo YY, Shen XW, Chen JC, Wu Q, Chen GQ. Production of copolyesters of 3-hydroxybutyrate and medium-chain-length 3-hydroxyalkanoates by E. coli containing an optimized PHA synthase gene. Microb Cell Fact 2012; 11:130. [PMID: 22978778 PMCID: PMC3503839 DOI: 10.1186/1475-2859-11-130] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Accepted: 09/12/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Microbial polyhydroxyalkanoates (PHA) are biopolyesters consisting of diverse monomers. PHA synthase PhaC2Ps cloned from Pseudomonas stutzeri 1317 is able to polymerize short-chain-length (scl) 3-hydroxybutyrate (3HB) monomers and medium-chain-length (mcl) 3-hydroxyalkanoates (3HA) with carbon chain lengths ranging from C6 to C12. However, the scl and mcl PHA production in Escherichia coli expressing PhaC2Ps is limited with very low PHA yield. RESULTS To improve the production of PHA with a wide range of monomer compositions in E. coli, a series of optimization strategies were applied on the PHA synthase PhaC2Ps. Codon optimization of the gene and mRNA stabilization with a hairpin structure were conducted and the function of the optimized PHA synthase was tested in E. coli. The transcript was more stable after the hairpin structure was introduced, and western blot analysis showed that both codon optimization and hairpin introduction increased the protein expression level. Compared with the wild type PhaC2Ps, the optimized PhaC2Ps increased poly-3-hydroxybutyrate (PHB) production by approximately 16-fold to 30% of the cell dry weight. When grown on dodecanoate, the recombinant E. coli harboring the optimized gene phaC2PsO with a hairpin structure in the 5' untranslated region was able to synthesize 4-fold more PHA consisting of 3HB and medium-chain-length 3HA compared to the recombinant harboring the wild type phaC2Ps. CONCLUSIONS The levels of both PHB and scl-mcl PHA in E. coli were significantly increased by series of optimization strategies applied on PHA synthase PhaC2Ps. These results indicate that strategies including codon optimization and mRNA stabilization are useful for heterologous PHA synthase expression and therefore enhance PHA production.
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Affiliation(s)
- Xue Gao
- MOE Key Lab of Bioinformatics, Department of Biological Science and Biotechnology, School of Life Science, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
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Chen GQ. New challenges and opportunities for industrial biotechnology. Microb Cell Fact 2012; 11:111. [PMID: 22905695 PMCID: PMC3520750 DOI: 10.1186/1475-2859-11-111] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 08/14/2012] [Indexed: 11/18/2022] Open
Abstract
Industrial biotechnology has not developed as fast as expected due to some challenges including the emergences of alternative energy sources, especially shale gas, natural gas hydrate (or gas hydrate) and sand oil et al. The weaknesses of microbial or enzymatic processes compared with the chemical processing also make industrial biotech products less competitive with the chemical ones. However, many opportunities are still there if industrial biotech processes can be as similar as the chemical ones. Taking advantages of the molecular biology and synthetic biology methods as well as changing process patterns, we can develop bioprocesses as competitive as chemical ones, these including the minimized cells, open and continuous fermentation processes et al.
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Affiliation(s)
- Guo-Qiang Chen
- MOE Key Lab of Bioinformatics and Systems Biology, Department of Biological Science and Biotechnology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, China.
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Li MC, Liu QQ, Lu XY, Zhang YL, Wang LL. Heterologous expression of human costimulatory molecule B7-2 and construction of B7-2 immobilized polyhydroxyalkanoate nanoparticles for use as an immune activation agent. BMC Biotechnol 2012; 12:43. [PMID: 22846711 PMCID: PMC3468374 DOI: 10.1186/1472-6750-12-43] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 07/25/2012] [Indexed: 11/10/2022] Open
Abstract
Background Costimulation of T cells via costimulatory molecules such as B7 is important for eliciting cell-mediated antitumor immunity. Presenting costimulation molecules by immobilizing recombinant B7 on the surface of nanovectors is a novel strategy for complementary therapy. Polyhydroxyalkanoates (PHAs) are a family of biodegradable, non-toxic, biocompatible polyesters, which can be used as a nonspecific immobilizing matrix for protein presentation. Recombinant protein fusion with PHA granule binding protein phasin (PhaP) can be easily immobilized on the surface of PHA nanoparticles through hydrophobic interactions between PhaP and PHA, and therefore provides a low-cost protein presenting strategy. Results In this study, the extracellular domain of the B7-2 molecule (also named as CD86) was fused with PhaP at its N-terminal and heterogeneously expressed in recombinant Escherichia coli strain BL21 (DE3). The purified B7-2-PhaP protein was immobilized on the surface of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx)-based nanoparticles. Loading of 240 μg (3.2 pMol) of B7-2-PhaP protein per mg nanoparticles was achieved. Immobilized B7-2-PhaP on PHBHHx nanoparticles induced T cell activation and proliferation in vitro. Conclusions A PHA nanoparticle-based B7-2 costimulation molecule-presenting system was constructed. The PHA-based B7 presenting nanosystem provided costimulation signals to induce T cell activation and expansion in vitro. The B7-2-PhaP immobilized PHA nanosystem is a novel strategy for costimulation molecule presentation and may be used for costimulatory molecule complementary therapy.
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Affiliation(s)
- Ming-Chuan Li
- Department of Biological Science and Bioengineering, Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, P.R, China
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Zhou XY, Yuan XX, Shi ZY, Meng DC, Jiang WJ, Wu LP, Chen JC, Chen GQ. Hyperproduction of poly(4-hydroxybutyrate) from glucose by recombinant Escherichia coli. Microb Cell Fact 2012; 11:54. [PMID: 22550959 PMCID: PMC3527305 DOI: 10.1186/1475-2859-11-54] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Accepted: 04/26/2012] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Poly(4-hydroxybutyrate) [poly(4HB)] is a strong thermoplastic biomaterial with remarkable mechanical properties, biocompatibility and biodegradability. However, it is generally synthesized when 4-hydroxybutyrate (4HB) structurally related substrates such as γ-butyrolactone, 4-hydroxybutyrate or 1,4-butanediol (1,4-BD) are provided as precursor which are much more expensive than glucose. At present, high production cost is a big obstacle for large scale production of poly(4HB).
Results
Recombinant Escherichia coli strain was constructed to achieve hyperproduction of poly(4-hydroxybutyrate) [poly(4HB)] using glucose as a sole carbon source. An engineering pathway was established in E. coli containing genes encoding succinate degradation of Clostridium kluyveri and PHB synthase of Ralstonia eutropha. Native succinate semialdehyde dehydrogenase genes sad and gabD in E. coli were both inactivated to enhance the carbon flux to poly(4HB) biosynthesis. Four PHA binding proteins (PhaP or phasins) including PhaP1, PhaP2, PhaP3 and PhaP4 from R. eutropha were heterologously expressed in the recombinant E. coli, respectively, leading to different levels of improvement in poly(4HB) production. Among them PhaP1 exhibited the highest capability for enhanced polymer synthesis. The recombinant E. coli produced 5.5 g L-1 cell dry weight containing 35.4% poly(4HB) using glucose as a sole carbon source in a 48 h shake flask growth. In a 6-L fermentor study, 11.5 g L-1 cell dry weight containing 68.2% poly(4HB) was obtained after 52 h of cultivation. This was the highest poly(4HB) yield using glucose as a sole carbon source reported so far. Poly(4HB) was structurally confirmed by gas chromatographic (GC) as well as 1H and 13C NMR studies.
Conclusions
Significant level of poly(4HB) biosynthesis from glucose can be achieved in sad and gabD genes deficient strain of E. coli JM109 harboring an engineering pathway encoding succinate degradation genes and PHB synthase gene, together with expression of four PHA binding proteins PhaP or phasins, respectively. Over 68% poly(4HB) was produced in a fed-batch fermentation process, demonstrating the feasibility for enhanced poly(4HB) production using the recombinant strain for future cost effective commercial development.
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Chen GQ, Patel MK. Plastics derived from biological sources: present and future: a technical and environmental review. Chem Rev 2011; 112:2082-99. [PMID: 22188473 DOI: 10.1021/cr200162d] [Citation(s) in RCA: 453] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Guo-Qiang Chen
- Department of Biological Sciences and Biotechnology, MOE Key Laboratory Bioinformatics (& System Biology), Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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Pfeiffer D, Wahl A, Jendrossek D. Identification of a multifunctional protein, PhaM, that determines number, surface to volume ratio, subcellular localization and distribution to daughter cells of poly(3-hydroxybutyrate), PHB, granules in Ralstonia eutropha H16. Mol Microbiol 2011; 82:936-51. [DOI: 10.1111/j.1365-2958.2011.07869.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Pfeiffer D, Jendrossek D. Interaction between poly(3-hydroxybutyrate) granule-associated proteins as revealed by two-hybrid analysis and identification of a new phasin in Ralstonia eutropha H16. Microbiology (Reading) 2011; 157:2795-2807. [DOI: 10.1099/mic.0.051508-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A large number of polypeptides are attached to poly(3-hydroxybutyrate) (PHB) granules of Ralstonia eutropha, such as PHB synthase (PhaC1), several PHB depolymerases (PhaZs) and phasins (PhaPs), the regulator protein PhaR
Reu
, and possibly others. In this study we used the bacterial adenylate cyclase-based two-hybrid assay to investigate interactions between known PHB granule-associated proteins (PGAPs) and to screen for new PGAPs. The utility of the system was tested by the in vivo verification of previously postulated interactions of the PHB synthase subunits of R. eutropha (PhaC1 homo-oligomerization) and of Bacillus megaterium (PhaC
Bmeg
–PhaR
Bmeg
hetero-oligomerization). Nine proteins (PhaA, PhaB1, PhaC1, PhaP1–PhaP4, PhaZ1 and PhaR), with established functions in PHB metabolism of R. eutropha, were tested for interaction in all combinations. While no significant interaction was detected between the PHB synthase PhaC1 and any of the other eight tested Pha proteins, strong interactions were found between all phasin proteins, in particular between PhaP2 and PhaP4. When PhaP2 was used as bait in a two-hybrid screening experiment with a genomic library of R. eutropha, the B1934 gene product was identified in 24 out of 53 isolated clones. B1934 encodes a hypothetical protein (15.7 kDa) with similarity to phasins of PHB-accumulating bacteria. A fusion protein of eYfp and the B1934 gene product colocalized with PHB granules, confirming that B1934 represents a new phasin (PhaP5). PhaP5 was not essential for PHB granule formation, but overexpression of PhaP5 increased the number of cells with PHB granules at the cell poles.
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Affiliation(s)
- Daniel Pfeiffer
- Institut für Mikrobiologie, Universität Stuttgart, Allmandring 31, Stuttgart, Germany
| | - Dieter Jendrossek
- Institut für Mikrobiologie, Universität Stuttgart, Allmandring 31, Stuttgart, Germany
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Jahns AC, Rehm BHA. Relevant uses of surface proteins--display on self-organized biological structures. Microb Biotechnol 2011; 5:188-202. [PMID: 21906264 PMCID: PMC3815779 DOI: 10.1111/j.1751-7915.2011.00293.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Proteins are often found attached to surfaces of self‐assembling biological units such as whole microbial cells or subcellular structures, e.g. intracellular inclusions. In the last two decades surface proteins were identified that could serve as anchors for the display of foreign protein functions. Extensive protein engineering based on structure–function data enabled efficient display of technically and/or medically relevant protein functions. Small size, diversity of the anchor protein as well as support structure, genetic manipulability and controlled cultivation of phages, bacterial cells and yeasts contributed to the establishment of designed and specifically functionalized tools for applications as sensors, catalysis, biomedicine, vaccine development and library‐based screening technologies. Traditionally, phage display is employed for library screening but applications in biomedicine and vaccine development are also perceived. For some diagnostic purposes phages are even too small in size so other carrier materials where needed and gave way for cell and yeast display. Only recently, intracellular inclusions such as magnetosomes, polyhydroxyalkanoate granules and lipid bodies were conceived as stable subcellular structures enabling the display of foreign protein functions and showing potential as specific and tailor‐made devices for medical and biotechnological applications.
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Affiliation(s)
- Anika C Jahns
- Institute of Molecular BioSciences, Massey University, Private Bag 11222, Palmerston North, New Zealand
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