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Dank A, Liu Y, Wen X, Lin F, Wiersma A, Boeren S, Smid EJ, Notebaart RA, Abee T. Ethylene glycol is metabolized to ethanol and acetate and induces expression of bacterial microcompartments in Propionibacterium freudenreichii. Heliyon 2024; 10:e33444. [PMID: 39027605 PMCID: PMC11255663 DOI: 10.1016/j.heliyon.2024.e33444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 06/17/2024] [Accepted: 06/21/2024] [Indexed: 07/20/2024] Open
Abstract
Ethylene glycol (EG, 1,2-ethanediol) is a two-carbon dihydroxy alcohol that can be derived from fermentation of plant-derived xylose and arabinose and which can be formed during food fermentations. Here we show that Propionibacterium freudenreichii DSM 20271 is able to convert EG in anaerobic conditions to ethanol and acetate in almost equimolar amounts. The metabolism of EG led to a moderate increase of biomass, indicating its metabolism is energetically favourable. A proteomic analysis revealed EG induced expression of the pdu-cluster, which encodes a functional bacterial microcompartment (BMC) involved in the degradation of 1,2-propanediol, with the presence of BMCs confirmed using transmission electron microscopy. Cross-examination of the proteomes of 1,2-propanediol and EG grown cells revealed PDU BMC-expressing cells have elevated levels of DNA repair proteins and cysteine biosynthesis proteins. Cells grown in 1,2-propanediol and EG also showed enhanced resistance against acid and bile salt-induced stresses compared to lactate-grown cells. Our analysis of whole genome sequences of selected genomes of BMC-encoding microorganisms able to metabolize EG with acetaldehyde as intermediate indicate a potentially broad-distributed role of the pdu operon in metabolism of EG. Based on our results we conclude EG is metabolized to acetate and ethanol with acetaldehyde as intermediate within BMCs in P. freudenreichii.
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Affiliation(s)
- Alexander Dank
- Food Microbiology, Wageningen University and Research, Wageningen, Netherlands
| | - Yue Liu
- Food Microbiology, Wageningen University and Research, Wageningen, Netherlands
| | - Xin Wen
- Food Microbiology, Wageningen University and Research, Wageningen, Netherlands
| | - Fan Lin
- Food Microbiology, Wageningen University and Research, Wageningen, Netherlands
| | - Anne Wiersma
- Food Microbiology, Wageningen University and Research, Wageningen, Netherlands
| | - Sjef Boeren
- Laboratory of Biochemistry, Wageningen University and Research, Wageningen, Netherlands
| | - Eddy J. Smid
- Food Microbiology, Wageningen University and Research, Wageningen, Netherlands
| | | | - Tjakko Abee
- Food Microbiology, Wageningen University and Research, Wageningen, Netherlands
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2
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Chung H, Kim J, Lee YJ, Choi KR, Jeong KJ, Kim GJ, Lee SY. Enhanced production of difficult-to-express proteins through knocking down rnpA gene expression. Biotechnol J 2023; 18:e2200641. [PMID: 37285237 DOI: 10.1002/biot.202200641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Revised: 05/21/2023] [Accepted: 06/02/2023] [Indexed: 06/09/2023]
Abstract
Escherichia coli has been employed as a workhorse for the efficient production of recombinant proteins. However, some proteins were found to be difficult to produce in E. coli. The stability of mRNA has been considered as one of the important factors affecting recombinant protein production. Here we report a generally applicable and simple strategy for enhancing mRNA stability, and consequently improving recombinant protein production in E. coli. RNase P, a ribozyme comprising an RNA subunit (RnpB) and a protein subunit (RnpA), is involved in tRNA maturation. Based on the finding that purified RnpA can digest rRNA and mRNA in vitro, it was reasoned that knocking down the level of RnpA might enhance recombinant protein production. For this, the synthetic small regulatory RNA-based knockdown system was applied to reduce the expression level of RnpA. The developed RnpA knockdown system allowed successful overexpression of 23 different recombinant proteins of various origins and sizes, including Cas9 protein, antibody fragment, and spider silk protein. Notably, a 284.9-kDa ultra-high molecular weight, highly repetitive glycine-rich spider silk protein, which is one of the most difficult proteins to produce, could be produced to 1.38 g L-1 , about two-fold higher than the highest value previously achieved, by a fed-batch culture of recombinant E. coli strain employing the RnpA knockdown system. The RnpA-knockdown strategy reported here will be generally useful for the production of recombinant proteins including those that have been difficult to produce.
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Affiliation(s)
- Hannah Chung
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
- MedicosBiotech Inc, Daejeon, Republic of Korea
| | - Jiyong Kim
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
- MedicosBiotech Inc, Daejeon, Republic of Korea
| | - Yong Jae Lee
- Protein Engineering Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Republic of Korea
| | - Kyeong Rok Choi
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Ki Jun Jeong
- Protein Engineering Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Geun-Joong Kim
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju, Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 four), Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
- MedicosBiotech Inc, Daejeon, Republic of Korea
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3
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Kadeřábková N, Furniss RCD, Maslova E, Eisaiankhongi L, Bernal P, Filloux A, Landeta C, Gonzalez D, McCarthy RR, Mavridou DA. Antibiotic potentiation and inhibition of cross-resistance in pathogens associated with cystic fibrosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.02.551661. [PMID: 37577508 PMCID: PMC10418187 DOI: 10.1101/2023.08.02.551661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Critical Gram-negative pathogens, like Pseudomonas, Stenotrophomonas and Burkholderia, have become resistant to most antibiotics. Complex resistance profiles together with synergistic interactions between these organisms increase the likelihood of treatment failure in distinct infection settings, for example in the lungs of cystic fibrosis patients. Here, we discover that cell envelope protein homeostasis pathways underpin both antibiotic resistance and cross-protection in CF-associated bacteria. We find that inhibition of oxidative protein folding inactivates multiple species-specific resistance proteins. Using this strategy, we sensitize multi-drug resistant Pseudomonas aeruginosa to β-lactam antibiotics and demonstrate promise of new treatment avenues for the recalcitrant pathogen Stenotrophomonas maltophilia. The same approach also inhibits cross-protection between resistant S. maltophilia and susceptible P. aeruginosa, allowing eradication of both commonly co-occurring CF-associated organisms. Our results provide the basis for the development of next-generation strategies that target antibiotic resistance, while also impairing specific interbacterial interactions that enhance the severity of polymicrobial infections.
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Affiliation(s)
- Nikol Kadeřábková
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, 78712, Texas, USA
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
| | - R. Christopher D. Furniss
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
| | - Evgenia Maslova
- Division of Biosciences, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK
| | - Lara Eisaiankhongi
- Division of Biosciences, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK
| | - Patricia Bernal
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Seville, 41012, Spain
| | - Alain Filloux
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, 637551, Singapore
| | - Cristina Landeta
- Department of Biology, Indiana University, Bloomington, Indiana, 47405, USA
| | - Diego Gonzalez
- Laboratoire de Microbiologie, Institut de Biologie, Université de Neuchâtel, Neuchâtel, 2000, Switzerland
| | - Ronan R. McCarthy
- Division of Biosciences, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, UK
| | - Despoina A.I. Mavridou
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, 78712, Texas, USA
- John Ring LaMontagne Center for Infectious Diseases, The University of Texas at Austin, Austin, 78712, Texas, USA
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4
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Hu T, Yamaura M, Pham DM, Kasai T, Katayama A. Wide distribution of extracellular electron transfer functionality in natural proteinaceous organic materials for microbial reductive dehalogenation. J Biosci Bioeng 2023; 135:238-249. [PMID: 36646568 DOI: 10.1016/j.jbiosc.2022.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 11/23/2022] [Accepted: 12/09/2022] [Indexed: 01/16/2023]
Abstract
Extracellular electron transfer materials (EETMs) in the environment, such as humic substances and biochar, are formed from the humification/heating of natural organic materials. However, the distribution of extracellular electron transfer (EET) functionality in fresh natural organic materials has not yet been explored. In the present study, we reveal the wide distribution of EET functionality in proteinaceous materials for the first time using an anaerobic pentachlorophenol dechlorinating consortium, whose activity depends on EETM. Out of 11 natural organic materials and 13 reference compounds, seven proteinaceous organic materials (albumin, beef, milk, pork, soybean, yolk, and bovine serum albumin) functioned as EETMs. Carbohydrates and lipids did not function as EETMs. Comparative spectroscopic analyses suggested that a β-sheet secondary structure was essential for proteins to function as EETMs, regardless of water solubility. A high content of reduced sulfur was potentially involved in EET functionality. Although proteinaceous materials have thus far been considered simply as nutrients, the wide distribution of EET functionality in these materials provides new insights into their impact on biogeochemical cycles. In addition, structural information on EET functionality can provide a scientific basis for the development of eco-friendly EETMs.
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Affiliation(s)
- Tingting Hu
- Graduate School of Engineering, Nagoya University, Tokai National Higher Education and Research System, Chikusa, Nagoya 464-8603, Japan
| | - Mirai Yamaura
- Graduate School of Engineering, Nagoya University, Tokai National Higher Education and Research System, Chikusa, Nagoya 464-8603, Japan
| | - Duyen Minh Pham
- Institute of Materials and Systems for Sustainability, Nagoya University, Tokai National Higher Education and Research System, Chikusa, Nagoya 464-8603, Japan
| | - Takuya Kasai
- Graduate School of Engineering, Nagoya University, Tokai National Higher Education and Research System, Chikusa, Nagoya 464-8603, Japan; Institute of Materials and Systems for Sustainability, Nagoya University, Tokai National Higher Education and Research System, Chikusa, Nagoya 464-8603, Japan
| | - Arata Katayama
- Graduate School of Engineering, Nagoya University, Tokai National Higher Education and Research System, Chikusa, Nagoya 464-8603, Japan; Institute of Materials and Systems for Sustainability, Nagoya University, Tokai National Higher Education and Research System, Chikusa, Nagoya 464-8603, Japan.
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5
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Li W. Distinct enzymatic strategies for de novo generation of disulfide bonds in membranes. Crit Rev Biochem Mol Biol 2023; 58:36-49. [PMID: 37098102 PMCID: PMC10460286 DOI: 10.1080/10409238.2023.2201404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 04/02/2023] [Accepted: 04/06/2023] [Indexed: 04/26/2023]
Abstract
Disulfide bond formation is a catalyzed reaction essential for the folding and stability of proteins in the secretory pathway. In prokaryotes, disulfide bonds are generated by DsbB or VKOR homologs that couple the oxidation of a cysteine pair to quinone reduction. Vertebrate VKOR and VKOR-like enzymes have gained the epoxide reductase activity to support blood coagulation. The core structures of DsbB and VKOR variants share the architecture of a four-transmembrane-helix bundle that supports the coupled redox reaction and a flexible region containing another cysteine pair for electron transfer. Despite considerable similarities, recent high-resolution crystal structures of DsbB and VKOR variants reveal significant differences. DsbB activates the cysteine thiolate by a catalytic triad of polar residues, a reminiscent of classical cysteine/serine proteases. In contrast, bacterial VKOR homologs create a hydrophobic pocket to activate the cysteine thiolate. Vertebrate VKOR and VKOR-like maintain this hydrophobic pocket and further evolved two strong hydrogen bonds to stabilize the reaction intermediates and increase the quinone redox potential. These hydrogen bonds are critical to overcome the higher energy barrier required for epoxide reduction. The electron transfer process of DsbB and VKOR variants uses slow and fast pathways, but their relative contribution may be different in prokaryotic and eukaryotic cells. The quinone is a tightly bound cofactor in DsbB and bacterial VKOR homologs, whereas vertebrate VKOR variants use transient substrate binding to trigger the electron transfer in the slow pathway. Overall, the catalytic mechanisms of DsbB and VKOR variants have fundamental differences.
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Affiliation(s)
- Weikai Li
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
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6
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Lauretti-Ferreira F, Teixeira AAR, Giordano RJ, da Silva JB, Abreu PAE, Barbosa AS, Akamatsu MA, Ho PL. Characterization of a virulence-modifying protein of Leptospira interrogans identified by shotgun phage display. Front Microbiol 2022; 13:1051698. [PMID: 36519163 PMCID: PMC9742253 DOI: 10.3389/fmicb.2022.1051698] [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: 09/23/2022] [Accepted: 11/08/2022] [Indexed: 09/02/2023] Open
Abstract
Pathogenic species of Leptospira are etiologic agents of leptospirosis, an emerging zoonotic disease of worldwide extent and endemic in tropical regions. The growing number of identified leptospiral species sheds light to their genetic diversity and unique virulence mechanisms, many of them still remain unknown. Toxins and adhesins are important virulence factors in several pathogens, constituting promising antigens for the development of vaccines with cross-protection and long-lasting effect against leptospirosis. For this aim, we used the shotgun phage display technique to unravel new proteins with adhesive properties. A shotgun library was constructed using fragmented genomic DNA from Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130 and pG8SAET phagemid vector. Selection of phages bearing new possible cell-binding antigens was performed against VERO cells, using BRASIL biopanning methodology. Analysis of selected clones revealed the hypothetical protein LIC10778, a potentially exposed virulence factor that belongs to the virulence-modifying (VM) protein family (PF07598), composed of 13 members in the leptospiral strain Fiocruz L1-130. Prediction of LIC10778 tertiary structure indicates that the protein contains a cellular-binding domain (N-terminal portion) and an unknown domain of no assigned activity (C-terminal portion). The predicted N-terminal domain shared structural similarities with the cell-binding and internalization domain of toxins like Ricin and Abrin, as well as to the Community-Acquired Respiratory Distress Syndrome (CARDS) toxin in Mycoplasma pneumoniae. Interestingly, recombinant portions of the N-terminal region of LIC10778 protein showed binding to laminin, collagens I and IV, vitronectin, and plasma and cell fibronectins using overlay blotting technique, especially regarding the binding site identified by phage display. These data validate our preliminary phage display biopanning and support the predicted three-dimensional models of LIC10778 protein and other members of PF07598 protein family, confirming the identification of the N-terminal cell-binding domains that are similar to ricin-like toxins. Moreover, fluorescent fused proteins also confirmed that N-terminal region of LIC10778 is capable of binding to VERO and A549 cell lines, further highlighting its virulence role during host-pathogen interaction in leptospirosis probably mediated by its C-terminal domain. Indeed, recent results in the literature confirmed this assumption by demonstrating the cytotoxicity of a closely related PF07598 member.
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Affiliation(s)
- Fabiana Lauretti-Ferreira
- Bioindustrial Division, Butantan Institute, São Paulo, Brazil
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | - Ricardo José Giordano
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | | | | | | | - Paulo Lee Ho
- Bioindustrial Division, Butantan Institute, São Paulo, Brazil
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
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7
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Suzuki M, Date M, Kashiwagi T, Suzuki E, Yokoyama K. Rational design of a disulfide bridge increases the thermostability of microbial transglutaminase. Appl Microbiol Biotechnol 2022; 106:4553-4562. [PMID: 35729274 DOI: 10.1007/s00253-022-12024-8] [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: 02/19/2022] [Revised: 06/06/2022] [Accepted: 06/09/2022] [Indexed: 11/02/2022]
Abstract
Microbial transglutaminase (MTG) has numerous industrial applications in the food and pharmaceutical sectors. Unfortunately, the thermostability of MTG is too low to tolerate the desired conditions used in many of these commercial processes. In a previous study, we used protein engineering to improve the thermostability of MTG. Specifically, we generated a T7C/E58C mutant of MTG from Streptomyces mobaraensis that displayed enhanced resistance to thermal inactivation. In this study, a rational structure-based approach was adopted to introduce a disulfide bridge to further increase the thermostability of MTG. In all, four new mutants, each containing a novel disulfide bond, were engineered. Of these four mutants, D3C/G283C showed the most promising thermostability with a significantly higher ∆T50 (defined as the temperature of incubation at which 50% of the initial activity remains) of + 9 °C by comparison to wild-type MTG. Indeed, D3C/G283C combined enhanced thermostability with a 2.1-fold increased half-life at 65 °C compared with the wild-type enzyme. By structure-based rational design, we were able to create an MTG variant which might be useful for expanding the scope of application in food. KEY POINTS: • Microbial transglutaminase (MTG) is an enzyme used in many food applications • The applicability of MTG to various industrial processes other than the food sector is being investigated • Improvement of thermostability was confirmed for the disulfide bridge mutant D3C/G283C.
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Affiliation(s)
- Mototaka Suzuki
- Institute for Innovation, Ajinomoto Co., Inc., 1-1, Suzuki-cho, Kawasaki-shi, Kanagawa, 210-8681, Japan
| | - Masayo Date
- Institute for Innovation, Ajinomoto Co., Inc., 1-1, Suzuki-cho, Kawasaki-shi, Kanagawa, 210-8681, Japan
| | - Tatsuki Kashiwagi
- Institute for Innovation, Ajinomoto Co., Inc., 1-1, Suzuki-cho, Kawasaki-shi, Kanagawa, 210-8681, Japan
| | - Eiichiro Suzuki
- Institute for Innovation, Ajinomoto Co., Inc., 1-1, Suzuki-cho, Kawasaki-shi, Kanagawa, 210-8681, Japan.,Kihara Memorial Yokohama Foundation for the Advancement of Life Sciences Yokohama, Bio Industry Center, 1-6 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Keiichi Yokoyama
- Institute for Innovation, Ajinomoto Co., Inc., 1-1, Suzuki-cho, Kawasaki-shi, Kanagawa, 210-8681, Japan. .,R&B Planning Department, Ajinomoto Co., Inc, Tokyo, 104-8315, Japan.
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8
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Abstract
Auto-inducible promoter systems have been reported to increase soluble product formation in the periplasm of E. coli compared to inducer-dependent systems. In this study, we investigated the phosphate (PO4)-sensitive phoA expression system (pAT) for the production of a recombinant model antigen-binding fragment (Fab) in the periplasm of E. coli in detail. We explored the impact of non-limiting and limiting PO4 conditions on strain physiology as well as Fab productivity. We compared different methods for extracellular PO4 detection, identifying automated colorimetric measurement to be most suitable for at-line PO4 monitoring. We showed that PO4 limitation boosts phoA-based gene expression, however, the product was already formed at non-limiting PO4 conditions, indicating leaky expression. Furthermore, cultivation under PO4 limitation caused physiological changes ultimately resulting in a metabolic breakdown at PO4 starvation. Finally, we give recommendations for process optimization with the phoA expression system. In summary, our study provides very detailed information on the E. coli phoA expression system, thus extending the existing knowledge of this system, and underlines its high potential for the successful production of periplasmic products in E. coli.
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9
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Yu L, Cao Q, Chen W, Yang N, Yang CG, Ji Q, Wu M, Bae T, Lan L. A novel copper-sensing two-component system for inducing Dsb gene expression in bacteria. Sci Bull (Beijing) 2022; 67:198-212. [PMID: 36546013 DOI: 10.1016/j.scib.2021.03.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 01/15/2021] [Accepted: 03/01/2021] [Indexed: 01/06/2023]
Abstract
In nature, bacteria must sense copper and tightly regulate gene expression to evade copper toxicity. Here, we identify a new copper-responsive two-component system named DsbRS in the important human pathogen Pseudomonas aeruginosa; in this system, DsbS is a sensor histidine kinase, and DsbR, its cognate response regulator, directly induces the transcription of genes involved in protein disulfide bond formation (Dsb) (i.e., the dsbDEG operon and dsbB). In the absence of copper, DsbS acts as a phosphatase toward DsbR, thus blocking the transcription of Dsb genes. In the presence of copper, the metal ion directly binds to the sensor domain of DsbS, and the Cys82 residue plays a critical role in this process. The copper-binding behavior appears to inhibit the phosphatase activity of DsbS, leading to the activation of DsbR. The copper resistance of the dsbRS knock-out mutant is restored by the ectopic expression of the dsbDEG operon, which is a DsbRS major target. Strikingly, cognates of the dsbRS-dsbDEG pair are widely distributed across eubacteria. In addition, a DsbR-binding site, which contains the consensus sequence 5'-TTA-N8-TTAA-3', is detected in the promoter region of dsbDEG homologs in these species. These findings suggest that the regulation of Dsb genes by DsbRS represents a novel mechanism by which bacterial cells cope with copper stress.
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Affiliation(s)
- Liang Yu
- University of Chinese Academy of Sciences, Beijing 100049, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Qiao Cao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Weizhong Chen
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Nana Yang
- University of Chinese Academy of Sciences, Beijing 100049, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Cai-Guang Yang
- University of Chinese Academy of Sciences, Beijing 100049, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Quanjiang Ji
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Min Wu
- Department of Biomedical Sciences, University of North Dakota, Grand Forks ND 58203-9037, USA
| | - Taeok Bae
- Department of Microbiology and Immunology, Indiana University School of Medicine-Northwest, Gary IN 46408, USA
| | - Lefu Lan
- University of Chinese Academy of Sciences, Beijing 100049, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China; NMPA Key Laboratory for Testing Technology of Pharmaceutical Microbiology, Shanghai Institute for Food and Drug Control, Shanghai 201203, China.
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10
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Furniss RCD, Kaderabkova N, Barker D, Bernal P, Maslova E, Antwi AA, McNeil HE, Pugh HL, Dortet L, Blair JM, Larrouy-Maumus GJ, McCarthy RR, Gonzalez D, Mavridou DA. Breaking antimicrobial resistance by disrupting extracytoplasmic protein folding. eLife 2022; 11:57974. [PMID: 35025730 PMCID: PMC8863373 DOI: 10.7554/elife.57974] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 01/11/2022] [Indexed: 11/24/2022] Open
Abstract
Antimicrobial resistance in Gram-negative bacteria is one of the greatest threats to global health. New antibacterial strategies are urgently needed, and the development of antibiotic adjuvants that either neutralize resistance proteins or compromise the integrity of the cell envelope is of ever-growing interest. Most available adjuvants are only effective against specific resistance proteins. Here, we demonstrate that disruption of cell envelope protein homeostasis simultaneously compromises several classes of resistance determinants. In particular, we find that impairing DsbA-mediated disulfide bond formation incapacitates diverse β-lactamases and destabilizes mobile colistin resistance enzymes. Furthermore, we show that chemical inhibition of DsbA sensitizes multidrug-resistant clinical isolates to existing antibiotics and that the absence of DsbA, in combination with antibiotic treatment, substantially increases the survival of Galleria mellonella larvae infected with multidrug-resistant Pseudomonas aeruginosa. This work lays the foundation for the development of novel antibiotic adjuvants that function as broad-acting resistance breakers. Antibiotics, like penicillin, are the foundation of modern medicine, but bacteria are evolving to resist their effects. Some of the most harmful pathogens belong to a group called the 'Gram-negative bacteria', which have an outer layer – called the cell envelope – that acts as a drug barrier. This envelope contains antibiotic resistance proteins that can deactivate or repel antibiotics or even pump them out of the cell once they get in. One way to tackle antibiotic resistance could be to stop these proteins from working. Proteins are long chains of building blocks called amino acids that fold into specific shapes. In order for a protein to perform its role correctly, it must fold in the right way. In bacteria, a protein called DsbA helps other proteins fold correctly by holding them in place and inserting links called disulfide bonds. It was unclear whether DsbA plays a role in the folding of antibiotic resistance proteins, but if it did, it might open up new ways to treat antibiotic resistant infections. To find out more, Furniss, Kaderabkova et al. collected the genes that code for several antibiotic resistance proteins and put them into Escherichia coli bacteria, which made the bacteria resistant to antibiotics. Furniss, Kaderabkova et al. then stopped the modified E. coli from making DsbA, which led to the antibiotic resistance proteins becoming unstable and breaking down because they could not fold correctly. Further experiments showed that blocking DsbA with a chemical inhibitor in other pathogenic species of Gram-negative bacteria made these bacteria more sensitive to antibiotics that they would normally resist. To demonstrate that using this approach could work to stop infections by these bacteria, Furniss, Kaderabkova et al. used Gram-negative bacteria that produced antibiotic resistance proteins but could not make DsbA to infect insect larvae. The larvae were then treated with antibiotics, which increased their survival rate, indicating that blocking DsbA may be a good approach to tackling antibiotic resistant bacteria. According to the World Health Organization, developing new treatments against Gram-negative bacteria is of critical importance, but the discovery of new drugs has ground to a halt. One way around this is to develop ways to make existing drugs work better. Making drugs that block DsbA could offer a way to treat resistant infections using existing antibiotics in the future.
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Affiliation(s)
| | - Nikol Kaderabkova
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
| | - Declan Barker
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Patricia Bernal
- Department of Microbiology, Universidad de Sevilla, Seville, Spain
| | - Evgenia Maslova
- Department of Life Sciences, Brunel University London, London, United Kingdom
| | - Amanda Aa Antwi
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Helen E McNeil
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Hannah L Pugh
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Laurent Dortet
- Department of Bacteriology-Hygiene, Paris-Sud University, Paris, France
| | - Jessica Ma Blair
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | | | - Ronan R McCarthy
- Department of Life Sciences, Brunel University London, London, United Kingdom
| | - Diego Gonzalez
- Department of Biology, University of Neuchatel, Neuchatel, Switzerland
| | - Despoina Ai Mavridou
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
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11
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Structural and Biochemical Characterization of Thioredoxin-2 from Deinococcus radiodurans. Antioxidants (Basel) 2021; 10:antiox10111843. [PMID: 34829714 PMCID: PMC8615215 DOI: 10.3390/antiox10111843] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 11/17/2021] [Accepted: 11/18/2021] [Indexed: 12/19/2022] Open
Abstract
Thioredoxin (Trx), a ubiquitous protein showing disulfide reductase activity, plays critical roles in cellular redox control and oxidative stress response. Trx is a member of the Trx system, comprising Trx, Trx reductase (TrxR), and a cognate reductant (generally reduced nicotinamide adenine dinucleotide phosphate, NADPH). Bacterial Trx1 contains only the Trx-fold domain, in which the active site CXXC motif that is critical for the disulfide reduction activity is located. Bacterial Trx2 contains an N-terminal extension, which forms a zinc-finger domain, including two additional CXXC motifs. The multi-stress resistant bacterium Deinococcus radiodurans encodes both Trx1 (DrTrx1) and Trx2 (DrTrx2), which act as members of the enzymatic antioxidant systems. In this study, we constructed Δdrtrx1 and Δdrtrx2 mutants and examined their survival rates under H2O2 treated conditions. Both drtrx1 and drtrx2 genes were induced following H2O2 treatment, and the Δdrtrx1 and Δdrtrx2 mutants showed a decrease in resistance toward H2O2, compared to the wild-type. Native DrTrx1 and DrTrx2 clearly displayed insulin and DTNB reduction activity, whereas mutant DrTrx1 and DrTrx2, which harbors the substitution of conserved cysteine to serine in its active site CXXC motif, showed almost no reduction activity. Mutations in the zinc binding cysteines did not fully eliminate the reduction activities of DrTrx2. Furthermore, we solved the crystal structure of full-length DrTrx2 at 1.96 Å resolution. The N-terminal zinc-finger domain of Trx2 is thought to be involved in Trx-target interaction and, from our DrTrx2 structure, the orientation of the zinc-finger domain of DrTrx2 and its interdomain interaction, between the Trx-fold domain and the zinc-finger domain, is clearly distinguished from those of the other Trx2 structures.
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12
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Enhanced Prodigiosin Production in Serratia marcescens JNB5-1 by Introduction of a Polynucleotide Fragment into the pigN 3' Untranslated Region and Disulfide Bonds into O-Methyl Transferase (PigF). Appl Environ Microbiol 2021; 87:e0054321. [PMID: 34232745 DOI: 10.1128/aem.00543-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In Serratia marcescens JNB5-1, prodigiosin was highly produced at 30°C, but it was noticeably repressed at ≥37°C. Our initial results demonstrated that both the production and the stability of the O-methyl transferase (PigF) and oxidoreductase (PigN) involved in the prodigiosin pathway in S. marcescens JNB5-1 sharply decreased at ≥37°C. Therefore, in this study, we improved mRNA stability and protein production using de novo polynucleotide fragments (PNFs) and the introduction of disulfide bonds, respectively, and observed their effects on prodigiosin production. Our results demonstrate that adding PNFs at the 3' untranslated regions of pigF and pigN significantly improved the mRNA half-lives of these genes, leading to an increase in the transcript and expression levels. Subsequently, the introduction of disulfide bonds in pigF improved the thermal stability, pH stability, and copper ion resistance of PigF. Finally, shake flask fermentation showed that the prodigiosin titer with the engineered S. marcescens was increased by 61.38% from 5.36 to 8.65 g/liter compared to the JNB5-1 strain at 30°C and, significantly, the prodigiosin yield increased 2.05-fold from 0.38 to 0.78 g/liter at 37°C. In this study, we revealed that the introduction of PNFs and disulfide bonds greatly improved the expression and stability of pigF and pigN, hence efficiently enhancing prodigiosin production with S. marcescens at 30 and 37°C. IMPORTANCE This study highlights a promising strategy to improve mRNA/enzyme stability and to increase production using de novo PNF libraries and the introduction of disulfide bonds into the protein. PNFs could increase the half-life of target gene mRNA and effectively prevent its degradation. Moreover, PNFs could increase the relative intensity of target genes without affecting the expression of other genes; as a result, it could alleviate the cellular burden compared to other regulatory elements such as promoters. In addition, we obtained a PigF variant with improved activity and stability by the introduction of disulfide bonds into PigF. Collectively, we demonstrate here a novel approach for improving mRNA/enzyme stability using PNFs, which results in enhanced prodigiosin production in S. marcescens at 30°C.
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13
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Identification of a Thiol-Disulfide Oxidoreductase (SdbA) Catalyzing Disulfide Bond Formation in the Superantigen SpeA in Streptococcus pyogenes. J Bacteriol 2021; 203:e0015321. [PMID: 34152832 DOI: 10.1128/jb.00153-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mechanisms of disulfide bond formation in the human pathogen Streptococcus pyogenes are currently unknown. To date, no disulfide bond-forming thiol-disulfide oxidoreductase (TDOR) has been described and at least one disulfide bonded protein is known in S. pyogenes. This protein is the superantigen SpeA, which contains 3 cysteine residues (Cys 87, Cys90, and Cys98) and has a disulfide bond formed between Cys87 and Cys98. In this study, candidate TDORs were identified from the genome sequence of S. pyogenes MGAS8232. Using mutational and biochemical approaches, one of the candidate proteins, SpyM18_2037 (named here SdbA), was shown to be the catalyst that introduces the disulfide bond in SpeA. SpeA in the culture supernatant remained reduced when sdbA was inactivated and restored to the oxidized state when a functional copy of sdbA was returned to the sdbA-knockout mutant. SdbA has a typical C46XXC49 active site motif commonly found in TDORs. Site-directed mutagenesis experiments showed that the cysteines in the CXXC motif were required for the disulfide bond in SpeA to form. Interactions between SdbA and SpeA were examined using cysteine variant proteins. The results showed that SdbAC49A formed a mixed disulfide with SpeAC87A, suggesting that the N-terminal Cys46 of SdbA and the C-terminal Cys98 of SpeA participated in the initial reaction. SpeA oxidized by SdbA displayed biological activities suggesting that SpeA was properly folded following oxidation by SdbA. In conclusion, formation of the disulfide bond in SpeA is catalyzed by SdbA and the findings represent the first report of disulfide bond formation in S. pyogenes. IMPORTANCE Here, we reported the first example of disulfide bond formation in Streptococcus pyogenes. The results showed that a thiol-disulfide oxidoreductase, named SdbA, is responsible for introducing the disulfide bond in the superantigen SpeA. The cysteine residues in the CXXC motif of SdbA are needed for catalyzing the disulfide bond in SpeA. The disulfide bond in SpeA and neighboring amino acids form a disulfide loop that is conserved among many superantigens, including those from Staphylococcus aureus. SpeA and staphylococcal enterotoxins lacking the disulfide bond are biologically inactive. Thus, the discovery of the enzyme that catalyzes the disulfide bond in SpeA is important for understanding the biochemistry of SpeA production and presents a target for mitigating the virulence of S. pyogenes.
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14
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Kariuki CK, Magez S. Improving the yield of recalcitrant Nanobodies® by simple modifications to the standard protocol. Protein Expr Purif 2021; 185:105906. [PMID: 33991675 DOI: 10.1016/j.pep.2021.105906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/04/2021] [Accepted: 05/06/2021] [Indexed: 11/15/2022]
Abstract
Nanobodies are single-domain antibody constructs derived from the variable regions of heavy chain only (VHH) camelid IgGs. Their small size and single gene format make them amenable to various molecular biology applications that require a protein affinity-based approach. These features, in addition to their high solubility, allows their periplasmic expression, extraction and purification in E. coli systems with relative ease, using standardized protocols. However, some Nanobodies are recalcitrant to periplasmic expression, extraction and purification within E. coli systems. To improve their expression would require either a change in the expression host, vector or an increased scale of expression, all of which entail an increase in the complexity of their expression, and production cost. However, as shown here, specific changes in the existing standard E. coli culture protocol, aimed at reducing breakdown of selective antibiotic pressure, increasing the initial culture inoculum and improving transport to the periplasmic space, rescued the expression of several such refractory Nanobodies. The periplasmic extraction protocol was also changed to ensure efficient osmolysis, prevent both protein degradation and prevent downstream chelation of Ni2+ ions during IMAC purification. Adoption of this protocol will lead to an improvement of the expression of Nanobodies in general, and specifically, those that are recalcitrant.
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Affiliation(s)
- Christopher K Kariuki
- Laboratory of Cellular and Molecular Interactions (CMIM), Vrije Universiteit Brussels, Brussels, Belgium; Department of Tropical and Infectious Diseases, Institute of Primate Research (IPR), Nairobi, Kenya.
| | - Stefan Magez
- Laboratory of Cellular and Molecular Interactions (CMIM), Vrije Universiteit Brussels, Brussels, Belgium; Laboratory for Biomedical Research, Ghent University Global Campus, Yeonsu-Gu, Incheon, South Korea; Department of Biochemistry and Microbiology, Universiteit Gent, Ledeganckstraat 35, 9000, Gent, Belgium.
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15
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Arisawa M, Fukumoto K, Yamaguchi M. Rhodium-Catalyzed Oxidation of Unprotected Peptide Thiols to Disulfides with Oxygen in Water. ACS Catal 2020. [DOI: 10.1021/acscatal.0c04799] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Mieko Arisawa
- Department of Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Sendai 980-8578, Japan
| | - Kohei Fukumoto
- Department of Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Sendai 980-8578, Japan
| | - Masahiko Yamaguchi
- Department of Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Sendai 980-8578, Japan
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16
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Roy P, Roy S, Sengupta N. Disulfide Reduction Allosterically Destabilizes the β-Ladder Subdomain Assembly within the NS1 Dimer of ZIKV. Biophys J 2020; 119:1525-1537. [PMID: 32946768 DOI: 10.1016/j.bpj.2020.08.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 08/13/2020] [Accepted: 08/31/2020] [Indexed: 12/14/2022] Open
Abstract
The Zika virus (ZIKV) was responsible for a recent debilitating epidemic that till date has no cure. A potential way to reduce ZIKV virulence is to limit the action of the nonstructural proteins involved in its viral replication. One such protein, NS1, encoded as a monomer by the viral genome, plays a major role via symmetric oligomerization. We examine the homodimeric structure of the dominant β-ladder segment of NS1 with extensive all atom molecular dynamics. We find it stably bounded by two spatially separated interaction clusters (C1 and C2) with significant differences in the nature of their interactions. Four pairs of distal, intramonomeric disulfide bonds are found to be coupled to the stability, local structure, and wettability of the interfacial region. Symmetric reduction of the intramonomeric disulfides triggers marked dynamical heterogeneity, interfacial wettability, and asymmetric salt-bridging propensity. Harnessing the model-free Lipari-Szabo based formalism for estimation of conformational entropy (Sconf), we find clear signatures of heterogeneity in the monomeric conformational entropies. The observed asymmetry, very small in the unperturbed state, expands significantly in the reduced states. This allosteric effect is most noticeable in the electrostatically bound C2 cluster that underlies the greatest stability in the unperturbed state. Allosteric induction of conformational and thermodynamic asymmetry is expected to affect the pathways leading to symmetric higher-ordered oligomerization, and thereby affect crucial replication pathways.
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Affiliation(s)
- Priti Roy
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India
| | - Subhajit Roy
- Centre for Excellence in Basic Sciences (CBS), University of Mumbai, Vidyanagari, Mumbai, India
| | - Neelanjana Sengupta
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India.
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17
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Pulido IY, Prieto E, Pieffet GP, Méndez L, Jiménez-Junca CA. Functional Heterologous Expression of Mature Lipase LipA from Pseudomonas aeruginosa PSA01 in Escherichia coli SHuffle and BL21 (DE3): Effect of the Expression Host on Thermal Stability and Solvent Tolerance of the Enzyme Produced. Int J Mol Sci 2020; 21:E3925. [PMID: 32486240 PMCID: PMC7312249 DOI: 10.3390/ijms21113925] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 05/23/2020] [Accepted: 05/26/2020] [Indexed: 02/06/2023] Open
Abstract
This study aimed to express heterologously the lipase LipA from Pseudomonas aeruginosa PSA01 obtained from palm fruit residues. In previous approaches, LipA was expressed in Escherichia coli fused with its signal peptide and without its disulfide bond, displaying low activity. We cloned the mature LipA with its truncated chaperone Lif in a dual plasmid and overexpressed the enzyme in two E. coli strains: the traditional BL21 (DE3) and the SHuffle® strain, engineered to produce stable cytoplasmic disulfide bonds. We evaluated the effect of the disulfide bond on LipA stability using molecular dynamics. We expressed LipA successfully under isopropyl β-d-1-thio-galactopyranoside (IPTG) and slow autoinducing conditions. The SHuffle LipA showed higher residual activity at 45 °C and a greater hyperactivation after incubation with ethanol than the enzyme produced by E. coli BL21 (DE3). Conversely, the latter was slightly more stable in methanol 50% and 60% (t½: 49.5 min and 9 min) than the SHuffle LipA (t½: 31.5 min and 7.4 min). The molecular dynamics simulations showed that removing the disulfide bond caused some regions of LipA to become less flexible and some others to become more flexible, significantly affecting the closing lid and partially exposing the active site at all times.
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Affiliation(s)
- Ingrid Yamile Pulido
- Biosciences Doctoral Program, Universidad de La Sabana, km 7 Autopista Norte, Chía 250001, Colombia;
| | - Erlide Prieto
- Agro-industrial Processes Research Group, Engineering Faculty, Universidad de La Sabana, km 7 Autopista Norte, Chía, Cundinamarca 250001, Colombia; (E.P.); (L.M.)
| | - Gilles Paul Pieffet
- Science Faculty, Universidad Antonio Nariño, Calle 58 A # 37–94 Bogotá D.C.111511, Colombia;
| | - Lina Méndez
- Agro-industrial Processes Research Group, Engineering Faculty, Universidad de La Sabana, km 7 Autopista Norte, Chía, Cundinamarca 250001, Colombia; (E.P.); (L.M.)
| | - Carlos A. Jiménez-Junca
- Bioprospecting Research Group, Engineering Faculty, Universidad de La Sabana, km 7 Autopista Norte, Chía, Cundinamarca 250001, Colombia
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18
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Giachino A, Waldron KJ. Copper tolerance in bacteria requires the activation of multiple accessory pathways. Mol Microbiol 2020; 114:377-390. [DOI: 10.1111/mmi.14522] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/18/2020] [Accepted: 04/20/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Andrea Giachino
- Biosciences Institute Faculty of Medical Sciences Newcastle University Newcastle upon Tyne UK
| | - Kevin J. Waldron
- Biosciences Institute Faculty of Medical Sciences Newcastle University Newcastle upon Tyne UK
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19
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Cao X, Lilla S, Cao Z, Pringle MA, Oka OBV, Robinson PJ, Szmaja T, van Lith M, Zanivan S, Bulleid NJ. The mammalian cytosolic thioredoxin reductase pathway acts via a membrane protein to reduce ER-localised proteins. J Cell Sci 2020; 133:jcs241976. [PMID: 32184267 PMCID: PMC7197872 DOI: 10.1242/jcs.241976] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 03/10/2020] [Indexed: 01/21/2023] Open
Abstract
Folding of proteins entering the mammalian secretory pathway requires the insertion of the correct disulfides. Disulfide formation involves both an oxidative pathway for their insertion and a reductive pathway to remove incorrectly formed disulfides. Reduction of these disulfides is crucial for correct folding and degradation of misfolded proteins. Previously, we showed that the reductive pathway is driven by NADPH generated in the cytosol. Here, by reconstituting the pathway using purified proteins and ER microsomal membranes, we demonstrate that the thioredoxin reductase system provides the minimal cytosolic components required for reducing proteins within the ER lumen. In particular, saturation of the pathway and its protease sensitivity demonstrates the requirement for a membrane protein to shuttle electrons from the cytosol to the ER. These results provide compelling evidence for the crucial role of the cytosol in regulating ER redox homeostasis, ensuring correct protein folding and facilitating the degradation of misfolded ER proteins.
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Affiliation(s)
- Xiaofei Cao
- Institute of Molecular, Cell and Systems Biology, College of Medical Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Sergio Lilla
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK
| | - Zhenbo Cao
- Institute of Molecular, Cell and Systems Biology, College of Medical Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Marie Anne Pringle
- Institute of Molecular, Cell and Systems Biology, College of Medical Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Ojore B V Oka
- Institute of Molecular, Cell and Systems Biology, College of Medical Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Philip J Robinson
- Institute of Molecular, Cell and Systems Biology, College of Medical Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Tomasz Szmaja
- Institute of Molecular, Cell and Systems Biology, College of Medical Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Marcel van Lith
- Institute of Molecular, Cell and Systems Biology, College of Medical Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Sara Zanivan
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, G61 1QH, UK
| | - Neil J Bulleid
- Institute of Molecular, Cell and Systems Biology, College of Medical Veterinary and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK
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20
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Lembke M, Höfler T, Walter AN, Tutz S, Fengler V, Schild S, Reidl J. Host stimuli and operator binding sites controlling protein interactions between virulence master regulator ToxR and ToxS in Vibrio cholerae. Mol Microbiol 2020; 114:262-278. [PMID: 32251547 PMCID: PMC7496328 DOI: 10.1111/mmi.14510] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 03/27/2020] [Accepted: 03/28/2020] [Indexed: 02/06/2023]
Abstract
Protein-protein interactions (PPIs) are key mechanisms in the maintenance of biological regulatory networks. Herein, we characterize PPIs within ToxR and its co-activator, ToxS, to understand the mechanisms of ToxR transcription factor activation. ToxR is a key transcription activator that is supported by ToxS for virulence gene regulation in Vibrio cholerae. ToxR comprises a cytoplasmic DNA-binding domain that is linked by a transmembrane domain to a periplasmic signal receiver domain containing two cysteine residues. ToxR-ToxR and ToxR-ToxS PPIs were detected using an adenylate-cyclase-based bacterial two-hybrid system approach in Escherichia coli. We found that the ToxR-ToxR PPIs are significantly increased in response to ToxR operators, the co-activator ToxS and bile salts. We suggest that ToxS and bile salts promote the interaction between ToxR molecules that ultimately results in dimerization. Upon binding of operators, ToxR-ToxR PPIs are found at the highest frequency. Moreover, disulfide-bond-dependent interaction in the periplasm results in homodimer formation that is promoted by DNA binding. The formation of these homodimers and the associated transcriptional activity of ToxR were strongly dependent on the oxidoreductases DsbA/DsbC. These findings show that protein and non-protein partners, that either transiently or stably interact with ToxR, fine-tune ToxR PPIs, and its associated transcriptional activity in changing environments.
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Affiliation(s)
- Mareike Lembke
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Thomas Höfler
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | | | - Sarah Tutz
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Vera Fengler
- Division of Physiological Chemistry, Medical University of Graz, Graz, Austria
| | - Stefan Schild
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.,BioTechMed-Graz, Graz, Austria.,BioHealth, University of Graz, Graz, Austria
| | - Joachim Reidl
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.,BioTechMed-Graz, Graz, Austria.,BioHealth, University of Graz, Graz, Austria
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21
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Cloning, expression and characterization of a thermo-alkali-stable xylanase from Aspergillus oryzae LC1 in Escherichia coli BL21(DE3). Protein Expr Purif 2020; 168:105551. [DOI: 10.1016/j.pep.2019.105551] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/26/2019] [Accepted: 12/11/2019] [Indexed: 11/21/2022]
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22
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A Disulfide Oxidoreductase (CHU_1165) Is Essential for Cellulose Degradation by Affecting Outer Membrane Proteins in Cytophaga hutchinsonii. Appl Environ Microbiol 2020; 86:AEM.02789-19. [PMID: 32033954 DOI: 10.1128/aem.02789-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 01/19/2020] [Indexed: 11/20/2022] Open
Abstract
Cytophaga hutchinsonii cells can bind to the surface of insoluble cellulose and degrade it by utilizing a novel cell contact-dependent mechanism, in which the outer membrane proteins may play important roles. In this study, the deletion of a gene locus, chu_1165, which encodes a hypothetical protein with 32% identity with TlpB, a disulfide oxidoreductase in Flavobacterium psychrophilum, caused a complete cellulolytic defect in C. hutchinsonii Further study showed that cells of the Δ1165 strain could not bind to cellulose, and the levels of many outer membrane proteins that can bind to cellulose were significantly decreased. The N-terminal region of CHU_1165 is anchored to the cytoplasmic membrane with five predicted transmembrane helices, and the C-terminal region is predicted to stretch to the periplasm and has a similar thioredoxin (Trx) fold containing a Cys-X-X-Cys motif that is conserved in disulfide oxidoreductases. Recombinant CHU_1165His containing the Cys-X-X-Cys motif was able to reduce the disulfide bonds of insulin in vitro Site-directed mutation showed that the cysteines in the Cys-X-X-Cys motif and at residues 106 and 108 were indispensable for the function of CHU_1165. Western blotting showed that CHU_1165 was in an oxidized state in vivo, suggesting that it may act as an oxidase to catalyze disulfide bond formation. However, many of the decreased outer membrane proteins that were essential for cellulose degradation contained no or one cysteine, and mutation of the cysteine in these proteins did not affect cellulose degradation, indicating that CHU_1165 may have an indirect or pleiotropic effect on the function of these outer membrane proteins.IMPORTANCE Cytophaga hutchinsonii can rapidly digest cellulose in a contact-dependent manner, in which the outer membrane proteins may play important roles. In this study, a hypothetical protein, CHU_1165, characterized as a disulfide oxidoreductase, is essential for cellulose degradation by affecting the cellulose binding ability of many outer membrane proteins in C. hutchinsonii Disulfide oxidoreductases are involved in disulfide bond formation. However, our studies show that many of the decreased outer membrane proteins that were essential for cellulose degradation contained no or one cysteine, and mutation of cysteine did not affect their function, indicating that CHU_1165 did not facilitate the formation of a disulfide bond in these proteins. It may have an indirect or pleiotropic effect on the function of these outer membrane proteins. Our study provides an orientation for exploring the proteins that assist in the appropriate conformation of many outer membrane proteins essential for cellulose degradation, which is important for exploring the novel mechanism of cellulose degradation in C. hutchinsonii.
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Varas LR, Fantuzzi F, Coutinho LH, Bernini RB, Nascimento MAC, de Souza GGB. Are disulfide bonds resilient to double ionization? Insights from coincidence spectroscopy and ab initio calculations. RSC Adv 2020; 10:35039-35048. [PMID: 35515687 PMCID: PMC9056841 DOI: 10.1039/d0ra05979j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 09/14/2020] [Indexed: 11/21/2022] Open
Abstract
Disulfide bonds (–S–S–) are severely damaged as a consequence of sulfur core–shell ionization processes, which is related to their low thermodynamic stability in multiply-charged systems.
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Affiliation(s)
- Lautaro R. Varas
- Escuela de Ingeniería Química
- Universidad de Costa Rica
- Ciudad de la Investigación
- Facultad de Ingeniería
- 11501-2060 San José
| | - Felipe Fantuzzi
- Instituto de Química
- Universidade Federal do Rio de Janeiro
- Cidade Universitária
- 21949-909, Rio de Janeiro
- Brazil
| | | | - Rafael B. Bernini
- Instituto Federal de Ciência e Tecnologia do Rio de Janeiro (IFRJ)
- Duque de Caxias
- Brazil
| | | | - G. G. B. de Souza
- Instituto de Química
- Universidade Federal do Rio de Janeiro
- Cidade Universitária
- 21949-909, Rio de Janeiro
- Brazil
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24
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Won Y, Pagar AD, Patil MD, Dawson PE, Yun H. Recent Advances in Enzyme Engineering through Incorporation of Unnatural Amino Acids. BIOTECHNOL BIOPROC E 2019. [DOI: 10.1007/s12257-019-0163-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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25
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Bartelli NL, Sun S, Gucinski GC, Zhou H, Song K, Hayes CS, Dahlquist FW. The Cytoplasm-Entry Domain of Antibacterial CdiA Is a Dynamic α-Helical Bundle with Disulfide-Dependent Structural Features. J Mol Biol 2019; 431:3203-3216. [PMID: 31181288 PMCID: PMC6727969 DOI: 10.1016/j.jmb.2019.05.049] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 05/01/2019] [Accepted: 05/30/2019] [Indexed: 01/04/2023]
Abstract
Many Gram-negative bacterial species use contact-dependent growth inhibition (CDI) systems to compete with neighboring cells. CDI+ strains express cell-surface CdiA effector proteins, which carry a toxic C-terminal region (CdiA-CT) that is cleaved from the effector upon transfer into the periplasm of target bacteria. The released CdiA-CT consists of two domains. The C-terminal domain is typically a nuclease that inhibits cell growth, and the N-terminal "cytoplasm-entry" domain mediates toxin translocation into the target-cell cytosol. Here, we use NMR and circular dichroism spectroscopic approaches to probe the structure, stability, and dynamics of the cytoplasm-entry domain from Escherichia coli STEC_MHI813. Chemical shift analysis reveals that the CdiA-CTMHI813 entry domain is composed of a C-terminal helical bundle and a dynamic N-terminal region containing two disulfide linkages. Disruption of the disulfides by mutagenesis or chemical reduction destabilizes secondary structure over the N-terminus, but has no effect on the C-terminal helices. Although critical for N-terminal structure, the disulfides have only modest effects on global thermodynamic stability, and the entry domain exhibits characteristics of a molten globule. We find that the disulfides form in vivo as the entry domain dwells in the periplasm of inhibitor cells prior to target-cell recognition. CdiA-CTMHI813 variants lacking either disulfide still kill target bacteria, but disruption of both bonds abrogates growth inhibition activity. We propose that the entry domain's dynamic structural features are critical for function. In its molten globule-like state, the domain resists degradation after delivery, yet remains pliable enough to unfold for membrane translocation.
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Affiliation(s)
- Nicholas L Bartelli
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, United States
| | - Sheng Sun
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, United States
| | - Grant C Gucinski
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106, United States
| | - Hongjun Zhou
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, United States
| | - Kiho Song
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106, United States
| | - Christopher S Hayes
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106, United States; Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106, United States.
| | - Frederick W Dahlquist
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106, United States; Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106, United States; Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106, United States.
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26
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Napolitano S, Reber RJ, Rubini M, Glockshuber R. Functional analyses of ancestral thioredoxins provide insights into their evolutionary history. J Biol Chem 2019; 294:14105-14118. [PMID: 31366732 PMCID: PMC6755812 DOI: 10.1074/jbc.ra119.009718] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/29/2019] [Indexed: 12/24/2022] Open
Abstract
Thioredoxin (Trx) is a conserved, cytosolic reductase in all known organisms. The enzyme receives two electrons from NADPH via thioredoxin reductase (TrxR) and passes them on to multiple cellular reductases via disulfide exchange. Despite the ubiquity of thioredoxins in all taxa, little is known about the functions of resurrected ancestral thioredoxins in the context of a modern mesophilic organism. Here, we report on functional in vitro and in vivo analyses of seven resurrected Precambrian thioredoxins, dating back 1–4 billion years, in the Escherichia coli cytoplasm. Using synthetic gene constructs for recombinant expression of the ancestral enzymes, along with thermodynamic and kinetic assays, we show that all ancestral thioredoxins, as today's thioredoxins, exhibit strongly reducing redox potentials, suggesting that thioredoxins served as catalysts of cellular reduction reactions from the beginning of evolution, even before the oxygen catastrophe. A detailed, quantitative characterization of their interactions with the electron donor TrxR from Escherichia coli and the electron acceptor methionine sulfoxide reductase, also from E. coli, strongly hinted that thioredoxins and thioredoxin reductases co-evolved and that the promiscuity of thioredoxins toward downstream electron acceptors was maintained during evolution. In summary, our findings suggest that thioredoxins evolved high specificity for their sole electron donor TrxR while maintaining promiscuity to their multiple electron acceptors.
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Affiliation(s)
- Silvia Napolitano
- Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland
| | - Robin J Reber
- Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland
| | - Marina Rubini
- School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland
| | - Rudi Glockshuber
- Institute of Molecular Biology and Biophysics, Department of Biology, Swiss Federal Institute of Technology Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland
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27
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Nakamura Y, Inaba H, Matsuura K. Construction of Artificial Viral Capsids Encapsulating Short DNAs via Disulfide Bonds and Controlled Release of DNAs by Reduction. CHEM LETT 2019. [DOI: 10.1246/cl.190091] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Yoko Nakamura
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan
| | - Hiroshi Inaba
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan
- Center for Research on Green Sustainable Chemistry, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan
| | - Kazunori Matsuura
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan
- Center for Research on Green Sustainable Chemistry, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan
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28
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Yazawa K, Furusawa H. Entropy-Driven Mechanisms between Disulfide-Bond Formation Protein A (DsbA) and B (DsbB) in Escherichia coli. ACS OMEGA 2019; 4:8341-8349. [PMID: 31459922 PMCID: PMC6648927 DOI: 10.1021/acsomega.9b00474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 04/30/2019] [Indexed: 06/10/2023]
Abstract
A disulfide-bond formation system for nascent proteins in the Escherichia coli periplasm contains efficient electron transfer systems for the catalysis of oxidation. This electrochemical system has interesting implications in vivo. Disulfide bonds are formed by disulfide-bond formation protein A (DsbA), which contains two reactive cysteines. DsbA is reoxidized by a membrane protein, disulfide-bond formation protein B (DsbB), which has four catalytic cysteines. The oxidation of DsbA by DsbB seems energetically unfavorable on the basis of the redox potential. The oxidizing power of ubiquinone (UQ), which endogenously binds with DsbB, is believed to promote this reaction. However, using UQ-deficient DsbB, it was found that the oxidation of DsbA by DsbB proceeds independently of UQ. Thus, the reaction mechanism of DsbA oxidation by DsbB is under debate. In this study, we used the quartz crystal microbalance technique, which detects the intermediate complex between DsbA and DsbB during DsbA oxidation as a change in mass, to obtain kinetic parameters of DsbA oxidation under both the oxidized and reduced states of UQ at acidic and basic pH. In addition, we utilized sodium dodecyl sulfate polyacrylamide gel electrophoresis mobility shift assay technique to determine the pK a of the cysteine thiol groups in DsbA and DsbB. We found that DsbA oxidation proceeded independently of UQ and was greatly affected in kinetics by the shuffling of electrons among the four cysteine residues in DsbB, regardless of pH. These results suggest that DsbA oxidation is driven in an entropy-dependent manner, in which the electron-delocalized intermediate complex is stabilized by preventing a reverse reaction. These findings could contribute to the design of bio-inspired electrochemical systems for industrial applications.
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Affiliation(s)
- Kenjiro Yazawa
- Division
of Biological and Medical Fibers, Interdisciplinary Cluster for Cutting
Edge Research, Institute for Fiber Engineering, Shinshu University, 3-15-1 Tokida, Ueda City, Nagano 386-8567, Japan
- Department
of Biomolecular Engineering, Tokyo Institute
of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| | - Hiroyuki Furusawa
- Innovative
Flex Course for Frontier Organic Material Systems (iFront), Graduate
School of Science and Engineering, Yamagata
University, 4-3-16 Jonan, Yonezawa, Yamagata 992-8510, Japan
- Department
of Biomolecular Engineering, Tokyo Institute
of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
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29
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Ushioda R, Nagata K. Redox-Mediated Regulatory Mechanisms of Endoplasmic Reticulum Homeostasis. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a033910. [PMID: 30396882 DOI: 10.1101/cshperspect.a033910] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The endoplasmic reticulum (ER) is a dynamic organelle responsible for many cellular functions in eukaryotic cells. Proper redox conditions in the ER are necessary for the functions of many luminal pathways and the maintenance of homeostasis. The redox environment in the ER is oxidative compared with that of the cytosol, and a network of oxidoreductases centering on the protein disulfide isomerase (PDI)-Ero1α hub complex is constructed for efficient electron transfer. Although these oxidizing environments are advantageous for oxidative folding for protein maturation, electron transfer is strictly controlled by Ero1α structurally and spatially. The ER redox environment shifts to a reductive environment under certain stress conditions. In this review, we focus on the reducing reactions that maintain ER homeostasis and introduce their significance in an oxidative ER environment.
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Affiliation(s)
- Ryo Ushioda
- Laboratory of Molecular and Cellular Biology, Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan.,Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto 603-8555, Japan
| | - Kazuhiro Nagata
- Laboratory of Molecular and Cellular Biology, Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan.,Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto 603-8555, Japan
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30
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Identification of Redox Partners of the Thiol-Disulfide Oxidoreductase SdbA in Streptococcus gordonii. J Bacteriol 2019; 201:JB.00030-19. [PMID: 30804044 DOI: 10.1128/jb.00030-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 02/18/2019] [Indexed: 12/13/2022] Open
Abstract
We previously identified a novel thiol-disulfide oxidoreductase, SdbA, in Streptococcus gordonii that formed disulfide bonds in substrate proteins and played a role in multiple phenotypes. In this study, we used mutational, phenotypic, and biochemical approaches to identify and characterize the redox partners of SdbA. Unexpectedly, the results showed that SdbA has multiple redox partners, forming a complex oxidative protein-folding pathway. The primary redox partners of SdbA that maintain its active site in an oxidized state are a surface-exposed thioredoxin family lipoprotein called SdbB (Sgo_1171) and an integral membrane protein annotated as CcdA2. Inactivation of sdbB and ccdA2 simultaneously, but not individually, recapitulated the sdbA mutant phenotype. The sdbB-ccdA2 mutant had defects in a range of cellular processes, including autolysis, bacteriocin production, genetic competence, and extracellular DNA (eDNA) release. AtlS, the natural substrate of SdbA produced by the sdbB-ccdA2 mutant lacked activity and an intramolecular disulfide bond. The redox state of SdbA in the sdbB-ccdA2 mutant was found to be in a reduced form and was restored when sdbB and ccdA2 were knocked back into the mutant. In addition, we showed that SdbB formed a disulfide-linked complex with SdbA in the cell. Recombinant SdbB and CcdA2 exhibited oxidase activity and reoxidized reduced SdbA in vitro Collectively, our results demonstrate that S. gordonii uses multiple redox partners for oxidative protein folding.IMPORTANCE Streptococcus gordonii is a commensal bacterium of the human dental plaque. Previously, we identified an enzyme, SdbA, that forms disulfide bonds in substrate proteins and plays a role in a number of cellular processes in S. gordonii Here, we identified the redox partners of SdbA. We showed that SdbA has multiple redox partners, SdbB and CcdA2, forming a complex oxidative protein-folding pathway. This pathway is essential for autolysis, bacteriocin production, genetic competence, and extracellular DNA (eDNA) release in S. gordonii These cellular processes are considered to be important for the success of S. gordonii as a dental plaque organism. This is the first example of an oxidative protein-folding pathway in Gram-positive bacteria that consists of an enzyme that uses multiple redox partners to function.
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31
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Bashirova A, Pramanik S, Volkov P, Rozhkova A, Nemashkalov V, Zorov I, Gusakov A, Sinitsyn A, Schwaneberg U, Davari MD. Disulfide Bond Engineering of an Endoglucanase from Penicillium verruculosum to Improve Its Thermostability. Int J Mol Sci 2019; 20:E1602. [PMID: 30935060 PMCID: PMC6479618 DOI: 10.3390/ijms20071602] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 03/25/2019] [Accepted: 03/27/2019] [Indexed: 01/29/2023] Open
Abstract
Endoglucanases (EGLs) are important components of multienzyme cocktails used in the production of a wide variety of fine and bulk chemicals from lignocellulosic feedstocks. However, a low thermostability and the loss of catalytic performance of EGLs at industrially required temperatures limit their commercial applications. A structure-based disulfide bond (DSB) engineering was carried out in order to improve the thermostability of EGLII from Penicillium verruculosum. Based on in silico prediction, two improved enzyme variants, S127C-A165C (DSB2) and Y171C-L201C (DSB3), were obtained. Both engineered enzymes displayed a 15⁻21% increase in specific activity against carboxymethylcellulose and β-glucan compared to the wild-type EGLII (EGLII-wt). After incubation at 70 °C for 2 h, they retained 52⁻58% of their activity, while EGLII-wt retained only 38% of its activity. At 80 °C, the enzyme-engineered forms retained 15⁻22% of their activity after 2 h, whereas EGLII-wt was completely inactivated after the same incubation time. Molecular dynamics simulations revealed that the introduced DSB rigidified a global structure of DSB2 and DSB3 variants, thus enhancing their thermostability. In conclusion, this work provides an insight into DSB protein engineering as a potential rational design strategy that might be applicable for improving the stability of other enzymes for industrial applications.
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Affiliation(s)
- Anna Bashirova
- Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences, Moscow 119071, Russia.
| | - Subrata Pramanik
- Institute of Biotechnology, RWTH Aachen University, Aachen 52074, Worringerweg 3, Germany.
| | - Pavel Volkov
- Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences, Moscow 119071, Russia.
| | - Aleksandra Rozhkova
- Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences, Moscow 119071, Russia.
| | - Vitaly Nemashkalov
- G.K.Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino 142292, Moscow region, Russia.
| | - Ivan Zorov
- Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences, Moscow 119071, Russia.
- Department of Chemistry, M.V.Lomonosov Moscow State University, Moscow 119991, Russia.
| | - Alexander Gusakov
- Department of Chemistry, M.V.Lomonosov Moscow State University, Moscow 119991, Russia.
| | - Arkady Sinitsyn
- Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences, Moscow 119071, Russia.
- Department of Chemistry, M.V.Lomonosov Moscow State University, Moscow 119991, Russia.
| | - Ulrich Schwaneberg
- Institute of Biotechnology, RWTH Aachen University, Aachen 52074, Worringerweg 3, Germany.
- DWI-Leibniz Institut für Interaktive Materialien, Forckenbeckstrasse 50, Aachen 52056, Germany.
| | - Mehdi D Davari
- Institute of Biotechnology, RWTH Aachen University, Aachen 52074, Worringerweg 3, Germany.
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32
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Ruano-Gallego D, Fraile S, Gutierrez C, Fernández LÁ. Screening and purification of nanobodies from E. coli culture supernatants using the hemolysin secretion system. Microb Cell Fact 2019; 18:47. [PMID: 30857538 PMCID: PMC6410518 DOI: 10.1186/s12934-019-1094-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 02/25/2019] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND The hemolysin (Hly) secretion system of E. coli allows the one-step translocation of hemolysin A (HlyA) from the bacterial cytoplasm to the extracellular medium, without a periplasmic intermediate. In this work, we investigate whether the Hly secretion system of E. coli is competent to secrete a repertoire of functional single-domain VHH antibodies (nanobodies, Nbs), facilitating direct screening of VHH libraries and the purification of selected Nb from the extracellular medium. RESULTS We employed a phagemid library of VHHs obtained by immunization of a dromedary with three protein antigens from enterohemorrhagic E. coli (EHEC), namely, the extracellular secreted protein A (EspA), the extracellular C-terminal region of Intimin (Int280), and the translocated intimin receptor middle domain (TirM). VHH clones binding each antigen were enriched and amplified by biopanning, and subsequently fused to the C-terminal secretion signal of HlyA to be expressed and secreted in a E. coli strain carrying the Hly export machinery (HlyB, HlyD and TolC). Individual E. coli clones were grown and induced in 96-well microtiter plates, and the supernatants of the producing cultures directly used in ELISA for detection of Nbs binding EspA, Int280 and TirM. A set of Nb sequences specifically binding each of these antigens were identified, indicating that the Hly system is able to secrete a diversity of functional Nbs. We performed thiol alkylation assays demonstrating that Nbs are correctly oxidized upon secretion, forming disulphide bonds between cysteine pairs despite the absence of a periplasmic intermediate. In addition, we show that the secreted Nb-HlyA fusions can be directly purified from the supernatant of E. coli cultures, avoiding cell lysis and in a single affinity chromatography step. CONCLUSIONS Our data demonstrate the Hly secretion system of E. coli can be used as an expression platform for screening and purification of Nb binders from VHH repertories.
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Affiliation(s)
- David Ruano-Gallego
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus UAM-Cantoblanco, 28049 Madrid, Spain
| | - Sofía Fraile
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus UAM-Cantoblanco, 28049 Madrid, Spain
| | - Carlos Gutierrez
- Research Institute of Biomedical and Health Sciences, Veterinary Faculty, Universidad de Las Palmas de Gran Canaria (UPGC), 35413 Arucas, Las Palmas, Canary Islands Spain
| | - Luis Ángel Fernández
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus UAM-Cantoblanco, 28049 Madrid, Spain
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33
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Leow HC, Fischer K, Leow YC, Braet K, Cheng Q, McCarthy J. Cytoplasmic and periplasmic expression of recombinant shark VNAR antibody in Escherichia coli. Prep Biochem Biotechnol 2019; 49:315-327. [DOI: 10.1080/10826068.2019.1566145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Herng C. Leow
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Penang, Malaysia
| | - Katja Fischer
- Clinical Tropical Medicine Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Yee C. Leow
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Penang, Malaysia
| | - Katleen Braet
- Department of Research, BioMARIC, Zwijnaarde, Belgium
| | - Qin Cheng
- Clinical Tropical Medicine Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
- Department of Drug Resistance Diagnostics, Australian Army Malaria Institute, Brisbane, Australia
| | - James McCarthy
- Clinical Tropical Medicine Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
- School of Medicine, University of Queensland, Brisbane, Australia
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Kilgore HR, Raines RT. n→π* Interactions Modulate the Properties of Cysteine Residues and Disulfide Bonds in Proteins. J Am Chem Soc 2018; 140:17606-17611. [PMID: 30403347 DOI: 10.1021/jacs.8b09701] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Noncovalent interactions are ubiquitous in biology, taking on roles that include stabilizing the conformation of and assembling biomolecules, and providing an optimal environment for enzymatic catalysis. Here, we describe a noncovalent interaction that engages the sulfur atoms of cysteine residues and disulfide bonds in proteins-their donation of electron density into an antibonding orbital of proximal amide carbonyl groups. This n→ π* interaction tunes the reactivity of the CXXC motif, which is the critical feature of thioredoxin and other enzymes involved in redox homeostasis. In particular, an n→ π* interaction lowers the p Ka value of the N-terminal cysteine residue of the motif, which is the nucleophile that initiates catalysis. In addition, the interplay between disulfide n→ π* interactions and C5 hydrogen bonds leads to hyperstable β-strands. Finally, n→ π* interactions stabilize vicinal disulfide bonds, which are naturally diverse in function. These previously unappreciated n→ π* interactions are strong and underlie the ability of cysteine residues and disulfide bonds to engage in the structure and function of proteins.
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Affiliation(s)
- Henry R Kilgore
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Ronald T Raines
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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35
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Osaki T, Nakanishi T, Aoki M, Omizu T, Nishiura D, Kitamura M. Soluble Expression in Escherichia coli of a Single-Domain Antibody-Tumor Necrosis Factor α Fusion Protein Specific for Epidermal Growth Factor Receptor. Monoclon Antib Immunodiagn Immunother 2018; 37:20-25. [PMID: 29474158 DOI: 10.1089/mab.2017.0051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Tumor-targeted antibody-cytokine fusion proteins, called immunocytokines, are expected to be a useful platform for the development of effective antitumor therapeutic agents; however, their design and cost-efficient production remain as challenges. In this study, we constructed an antibody-cytokine fusion protein (Ia1-TNFα) comprising the single-domain antibody Ia1, which targets epidermal growth factor receptor (EGFR) overexpressed in epithelial tumors and a tumor necrosis factor α (TNFα) domain, which has antitumor activity. Ia1-TNFα was produced in a soluble form by using an Escherichia coli expression system, and after affinity purification of the culture supernatant, an yield of ∼2 mg/L of cell culture was obtained. Gel filtration analysis showed that Ia1-TNFα existed predominantly as a trimer, which is consistent with the multimerization state of TNFα. Ia1-TNFα exhibited approximately 7-fold lower TNFα biological activity than that of TNFα itself. Flow cytometric analysis revealed that Ia1-TNFα specifically bound to EGFR-expressing tumor cells and that its binding activity was higher than that of monovalent Ia1, suggesting that the fusion protein bound to the tumor cells multivalently. Altogether, these results show that fusion of TNFα with a single-domain antibody could be a cost-efficient means of producing antitumor therapeutic agents.
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Affiliation(s)
- Tomohiro Osaki
- Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University , Osaka, Japan
| | - Takeshi Nakanishi
- Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University , Osaka, Japan
| | - Motoshi Aoki
- Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University , Osaka, Japan
| | - Takahiro Omizu
- Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University , Osaka, Japan
| | - Daisuke Nishiura
- Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University , Osaka, Japan
| | - Masaya Kitamura
- Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University , Osaka, Japan
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36
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Feng Z, Ogasawara Y, Nomura S, Dairi T. Biosynthetic Gene Cluster of ad-Tryptophan-Containing Lasso Peptide, MS-271. Chembiochem 2018; 19:2045-2048. [DOI: 10.1002/cbic.201800315] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Indexed: 01/31/2023]
Affiliation(s)
- Zhi Feng
- Graduate School of Engineering; Hokkaido University; Sapporo Hokkaido 060-8628 Japan
| | - Yasushi Ogasawara
- Graduate School of Engineering; Hokkaido University; Sapporo Hokkaido 060-8628 Japan
| | - Satoshi Nomura
- Graduate School of Engineering; Hokkaido University; Sapporo Hokkaido 060-8628 Japan
| | - Tohru Dairi
- Graduate School of Engineering; Hokkaido University; Sapporo Hokkaido 060-8628 Japan
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37
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Reddy PT, Brinson RG, Hoopes JT, McClung C, Ke N, Kashi L, Berkmen M, Kelman Z. Platform development for expression and purification of stable isotope labeled monoclonal antibodies in Escherichia coli. MAbs 2018; 10:992-1002. [PMID: 30060704 PMCID: PMC6204800 DOI: 10.1080/19420862.2018.1496879] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The widespread use of monoclonal antibodies (mAbs) as a platform for therapeutic drug development in the pharmaceutical industry has led to an increased interest in robust experimental approaches for assessment of mAb structure, stability and dynamics. The ability to enrich proteins with stable isotopes is a prerequisite for the in-depth application of many structural and biophysical methods, including nuclear magnetic resonance (NMR), small angle neutron scattering, neutron reflectometry, and quantitative mass spectrometry. While mAbs can typically be produced with very high yields using mammalian cell expression, stable isotope labeling using cell culture is expensive and often impractical. The most common and cost-efficient approach to label proteins is to express proteins in Escherichia coli grown in minimal media; however, such methods for mAbs have not been reported to date. Here we present, for the first time, the expression and purification of a stable isotope labeled mAb from a genetically engineered E. coli strain capable of forming disulfide bonds in its cytoplasm. It is shown using two-dimensional NMR spectral fingerprinting that the unlabeled mAb and the mAb singly or triply labeled with 13C, 15N, 2H are well folded, with only minor structural differences relative to the mammalian cell-produced mAb that are attributed to the lack of glycosylation in the Fc domain. This advancement of an E. coli-based mAb expression platform will facilitate the production of mAbs for in-depth structural characterization, including the high resolution investigation of mechanisms of action.
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Affiliation(s)
- Prasad T Reddy
- a Biomolecular Labeling Laboratory, Institute for Bioscience and Biotechnology Research , National Institute of Standards and Technology and the University of Maryland , Rockville , MD , USA
| | - Robert G Brinson
- b Institute for Bioscience and Biotechnology Research , National Institute of Standards and Technology and the University of Maryland , Rockville , MD , USA
| | - J Todd Hoopes
- a Biomolecular Labeling Laboratory, Institute for Bioscience and Biotechnology Research , National Institute of Standards and Technology and the University of Maryland , Rockville , MD , USA
| | | | - Na Ke
- c New England Biolabs , Ipswich , MA , USA
| | - Lila Kashi
- a Biomolecular Labeling Laboratory, Institute for Bioscience and Biotechnology Research , National Institute of Standards and Technology and the University of Maryland , Rockville , MD , USA
| | | | - Zvi Kelman
- a Biomolecular Labeling Laboratory, Institute for Bioscience and Biotechnology Research , National Institute of Standards and Technology and the University of Maryland , Rockville , MD , USA
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Schönfelder J, Alonso-Caballero A, De Sancho D, Perez-Jimenez R. The life of proteins under mechanical force. Chem Soc Rev 2018; 47:3558-3573. [PMID: 29473060 DOI: 10.1039/c7cs00820a] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Although much of our understanding of protein folding comes from studies of isolated protein domains in bulk, in the cellular environment the intervention of external molecular machines is essential during the protein life cycle. During the past decade single molecule force spectroscopy techniques have been extremely useful to deepen our understanding of these interventional molecular processes, as they allow for monitoring and manipulating mechanochemical events in individual protein molecules. Here, we review some of the critical steps in the protein life cycle, starting with the biosynthesis of the nascent polypeptide chain in the ribosome, continuing with the folding supported by chaperones and the translocation into different cell compartments, and ending with proteolysis in the proteasome. Along these steps, proteins experience molecular forces often combined with chemical transformations, affecting their folding and structure, which are measured or mimicked in the laboratory by the application of force with a single molecule apparatus. These mechanochemical reactions can potentially be used as targets for fighting against diseases. Inspired by these insightful experiments, we devise an outlook on the emerging field of mechanopharmacology, which reflects an alternative paradigm for drug design.
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Gaur R, Yadav M, Gupta R, Arora G, Rana P, Sharma RK. Aerobic Oxidation of Thiols to Disulfides by Silver-Based Magnetic Catalyst. ChemistrySelect 2018. [DOI: 10.1002/slct.201703020] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Rashmi Gaur
- Green Chemistry Network Centre; Department of Chemistry; University of Delhi; Delhi-110007 India
| | - Manavi Yadav
- Green Chemistry Network Centre; Department of Chemistry; University of Delhi; Delhi-110007 India
| | - Radhika Gupta
- Green Chemistry Network Centre; Department of Chemistry; University of Delhi; Delhi-110007 India
| | - Gunjan Arora
- Green Chemistry Network Centre; Department of Chemistry; University of Delhi; Delhi-110007 India
| | - Pooja Rana
- Green Chemistry Network Centre; Department of Chemistry; University of Delhi; Delhi-110007 India
| | - Rakesh K. Sharma
- Green Chemistry Network Centre; Department of Chemistry; University of Delhi; Delhi-110007 India
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Landeta C, Boyd D, Beckwith J. Disulfide bond formation in prokaryotes. Nat Microbiol 2018; 3:270-280. [PMID: 29463925 DOI: 10.1038/s41564-017-0106-2] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 12/21/2017] [Indexed: 12/25/2022]
Abstract
Interest in protein disulfide bond formation has recently increased because of the prominent role of disulfide bonds in bacterial virulence and survival. The first discovered pathway that introduces disulfide bonds into cell envelope proteins consists of Escherichia coli enzymes DsbA and DsbB. Since its discovery, variations on the DsbAB pathway have been found in bacteria and archaea, probably reflecting specific requirements for survival in their ecological niches. One variation found amongst Actinobacteria and Cyanobacteria is the replacement of DsbB by a homologue of human vitamin K epoxide reductase. Many Gram-positive bacteria express enzymes involved in disulfide bond formation that are similar, but non-homologous, to DsbAB. While bacterial pathways promote disulfide bond formation in the bacterial cell envelope, some archaeal extremophiles express proteins with disulfide bonds both in the cytoplasm and in the extra-cytoplasmic space, possibly to stabilize proteins in the face of extreme conditions, such as growth at high temperatures. Here, we summarize the diversity of disulfide-bond-catalysing systems across prokaryotic lineages, discuss examples for understanding the biological basis of such systems, and present perspectives on how such systems are enabling advances in biomedical engineering and drug development.
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Affiliation(s)
- Cristina Landeta
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| | - Dana Boyd
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| | - Jon Beckwith
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA.
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Gupta D, Singh A, Khan AU. Nanoparticles as Efflux Pump and Biofilm Inhibitor to Rejuvenate Bactericidal Effect of Conventional Antibiotics. NANOSCALE RESEARCH LETTERS 2017; 12:454. [PMID: 28709374 PMCID: PMC5509568 DOI: 10.1186/s11671-017-2222-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/04/2017] [Indexed: 05/21/2023]
Abstract
The universal problem of bacterial resistance to antibiotic reflects a serious threat for physicians to control infections. Evolution in bacteria results in the development of various complex resistance mechanisms to neutralize the bactericidal effect of antibiotics, like drug amelioration, target modification, membrane permeability reduction, and drug extrusion through efflux pumps. Efflux pumps acquire a wide range of substrate specificity and also the tremendous efficacy for drug molecule extrusion outside bacterial cells. Hindrance in the functioning of efflux pumps may rejuvenate the bactericidal effect of conventional antibiotics. Efflux pumps also play an important role in the exclusion or inclusion of quorum-sensing biomolecules responsible for biofilm formation in bacterial cells. This transit movement of quorum-sensing biomolecules inside or outside the bacterial cells may get interrupted by impeding the functioning of efflux pumps. Metallic nanoparticles represent a potential candidate to block efflux pumps of bacterial cells. The application of nanoparticles as efflux pump inhibitors will not only help to revive the bactericidal effect of conventional antibiotics but will also assist to reduce biofilm-forming capacity of microbes. This review focuses on a novel and fascinating application of metallic nanoparticles in synergy with conventional antibiotics for efflux pump inhibition.
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Affiliation(s)
- Divya Gupta
- Medical Microbiology and Molecular Biology Lab., Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
- Department of Biotechnology, Mangalayatan University, Aligarh, 202145, India
| | - Ajeet Singh
- Department of Biotechnology, G. B. Pant Engineering College, Pauri, 246194, India
| | - Asad U Khan
- Medical Microbiology and Molecular Biology Lab., Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India.
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Fowler NJ, Blanford CF, de Visser SP, Warwicker J. Features of reactive cysteines discovered through computation: from kinase inhibition to enrichment around protein degrons. Sci Rep 2017; 7:16338. [PMID: 29180682 PMCID: PMC5703995 DOI: 10.1038/s41598-017-15997-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 10/26/2017] [Indexed: 02/07/2023] Open
Abstract
Large-scale characterisation of cysteine modification is enabling study of the physicochemical determinants of reactivity. We find that location of cysteine at the amino terminus of an α-helix, associated with activity in thioredoxins, is under-represented in human protein structures, perhaps indicative of selection against background reactivity. An amino-terminal helix location underpins the covalent linkage for one class of kinase inhibitors. Cysteine targets for S-palmitoylation, S-glutathionylation, and S-nitrosylation show little correlation with pKa values predicted from structures, although flanking sequences of S-palmitoylated sites are enriched in positively-charged amino acids, which could facilitate palmitoyl group transfer to substrate cysteine. A surprisingly large fraction of modified sites, across the three modifications, would be buried in native protein structure. Furthermore, modified cysteines are (on average) closer to lysine ubiquitinations than are unmodified cysteines, indicating that cysteine redox biology could be associated with protein degradation and degron recognition.
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Affiliation(s)
- Nicholas J Fowler
- The Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom.,School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Christopher F Blanford
- The Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom.,School of Materials, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Sam P de Visser
- The Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom.,School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Jim Warwicker
- The Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom. .,School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom.
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Delaunay-Moisan A, Ponsero A, Toledano MB. Reexamining the Function of Glutathione in Oxidative Protein Folding and Secretion. Antioxid Redox Signal 2017; 27:1178-1199. [PMID: 28791880 DOI: 10.1089/ars.2017.7148] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
SIGNIFICANCE Disturbance of glutathione (GSH) metabolism is a hallmark of numerous diseases, yet GSH functions are poorly understood. One key to this question is to consider its functional compartmentation. GSH is present in the endoplasmic reticulum (ER), where it competes with substrates for oxidation by the oxidative folding machinery, composed in eukaryotes of the thiol oxidase Ero1 and proteins from the disulfide isomerase family (protein disulfide isomerase). Yet, whether GSH is required for proper ER oxidative protein folding is a highly debated question. Recent Advances: Oxidative protein folding has been thoroughly dissected over the past decades, and its actors and their mode of action elucidated. Genetically encoded GSH probes have recently provided an access to subcellular redox metabolism, including the ER. CRITICAL ISSUES Of the few often-contradictory models of the role of GSH in the ER, the most popular suggest it serves as reducing power. Yet, as a reductant, GSH also activates Ero1, which questions how GSH can nevertheless support protein reduction. Hence, whether GSH operates in the ER as a reductant, an oxidant, or just as a "blank" compound mirroring ER/periplasm redox activity is a highly debated question, which is further stimulated by the puzzling occurrence of GSH in the Escherichia coli periplasmic "secretory" compartment, aside from the Dsb thiol-reducing and oxidase pathways. FUTURE DIRECTIONS Addressing the mechanisms controlling GSH traffic in and out of the ER/periplasm and its recycling will help address GSH function in secretion. In addition, as thioredoxin reductase was recently implicated in ER oxidative protein folding, the relative contribution of each of these two reducing pathways should now be addressed. Antioxid. Redox Signal. 27, 1178-1199.
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Affiliation(s)
- Agnès Delaunay-Moisan
- Institute for Integrative Biology of the Cell (I2BC), LSOC, SBIGEM, CEA, CNRS, Université Paris-Sud , Université Paris-Saclay, Gif-sur-Yvette, France
| | - Alise Ponsero
- Institute for Integrative Biology of the Cell (I2BC), LSOC, SBIGEM, CEA, CNRS, Université Paris-Sud , Université Paris-Saclay, Gif-sur-Yvette, France
| | - Michel B Toledano
- Institute for Integrative Biology of the Cell (I2BC), LSOC, SBIGEM, CEA, CNRS, Université Paris-Sud , Université Paris-Saclay, Gif-sur-Yvette, France
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Reduction potentials of protein disulfides and catalysis of glutathionylation and deglutathionylation by glutaredoxin enzymes. Biochem J 2017; 474:3799-3815. [DOI: 10.1042/bcj20170589] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 09/26/2017] [Accepted: 09/27/2017] [Indexed: 12/26/2022]
Abstract
Glutaredoxins (Grxs) are a class of GSH (glutathione)-dependent thiol–disulfide oxidoreductase enzymes. They use the cellular redox buffer GSSG (glutathione disulfide)/GSH directly to catalyze these exchange reactions. Grxs feature dithiol active sites and can shuttle rapidly between three oxidation states, namely dithiol Grx(SH)2, mixed disulfide Grx(SH)(SSG) and oxidized disulfide Grx(SS). Each is characterized by a distinct standard reduction potential . The values for the redox couple Grx(SS)/Grx(SH)2 are available, but a recent estimate differs by over 100 mV from the literature values. No estimates are available for for the mixed disulfide couple Grx(SH)(SSG)/(Grx(SH)2 + GSH). This work determined both and for two representative Grx enzymes, Homo sapiens HsGrx1 and Escherichia coli EcGrx1. The empirical approaches were verified rigorously to overcome the sensitivity of these redox-labile enzymes to experimental conditions. The classic method of acid ‘quenching’ was demonstrated to shift the thiol–disulfide redox equilibria. Both enzymes exhibit an (vs. SHE) at a pH of 7.0. Their values (−213 and −230 mV for EcGrx1 and HsGrx1, respectively) are slightly less negative than that () of the redox buffer GSSG/2GSH. Both and vary with log [GSH], but the former more sensitively by a factor of 2. This confers dual catalytic functions to a Grx enzyme as either an oxidase at low [GSH] or as a reductase at high [GSH]. Consequently, these enzymes can participate efficiently in either glutathionylation or deglutathionylation. The catalysis is demonstrated to proceed via a monothiol ping-pong mechanism relying on a single Cys residue only in the dithiol active site.
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Salema V, Fernández LÁ. Escherichia coli surface display for the selection of nanobodies. Microb Biotechnol 2017; 10:1468-1484. [PMID: 28772027 PMCID: PMC5658595 DOI: 10.1111/1751-7915.12819] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 07/12/2017] [Accepted: 07/13/2017] [Indexed: 12/29/2022] Open
Abstract
Nanobodies (Nbs) are the smallest functional antibody fragments known in nature and have multiple applications in biomedicine or environmental monitoring. Nbs are derived from the variable segment of camelid heavy chain-only antibodies, known as VHH. For selection, libraries of VHH gene segments from naïve, immunized animals or of synthetic origin have been traditionally cloned in E. coli phage display or yeast display systems, and clones binding the target antigen recovered, usually from plastic surfaces with the immobilized antigen (phage display) or using fluorescence-activated cell sorting (FACS; yeast display). This review briefly describes these conventional approaches and focuses on the distinct properties of an E. coli display system developed in our laboratory, which combines the benefits of both phage display and yeast display systems. We demonstrate that E. coli display using an N-terminal domain of intimin is an effective platform for the surface display of VHH libraries enabling selection of high-affinity Nbs by magnetic cell sorting and direct selection on live mammalian cells displaying the target antigen on their surface. Flow cytometry analysis of E. coli bacteria displaying the Nbs on their surface allows monitoring of the selection process, facilitates screening, characterization of antigen-binding clones, specificity, ligand competition and estimation of the equilibrium dissociation constant (KD ).
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Affiliation(s)
- Valencio Salema
- Department of Microbial BiotechnologyCentro Nacional de Biotecnología (CNB)Consejo Superior de Investigaciones Científicas (CSIC)MadridSpain
| | - Luis Ángel Fernández
- Department of Microbial BiotechnologyCentro Nacional de Biotecnología (CNB)Consejo Superior de Investigaciones Científicas (CSIC)MadridSpain
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Lagzian M, Shahraki A, Besharatian M, Asoodeh A. A thermostable alkaliphilic protein-disulfide isomerase from Bacillus subtilis DR8806: cloning, expression, biochemical characterization and molecular dynamics simulation. Int J Biol Macromol 2017; 107:703-712. [PMID: 28919531 DOI: 10.1016/j.ijbiomac.2017.09.033] [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: 09/03/2017] [Revised: 09/09/2017] [Accepted: 09/13/2017] [Indexed: 11/16/2022]
Abstract
Disulfide bonds are among the most important factors related to correct folding of the proteins. Protein disulfide isomerase (PDI) is the enzyme responsible for the correct formation and isomerization of these bonds. It is rarely studied so far and none of them showed industrial properties. In this study, the gene encoding for a putative PDI from Bacillus subtilis DR8806 was identified, cloned and expressed in Escherichia coli. It was encoded a 23.26kDa protein. The enzyme was purified by GST affinity chromatography with a specific activity of 1227u/mg. It was active and stable over a wide range of temperature (20-85°C) and pH (4.5-10) with an optimum at 65°C and pH 5.5. Its activity was enhanced by Mn2+ and Co2+ while Ag+ and Zn2+ decreased it. Some of the known PDI inhibitors such as Tocinoic acid and Bactiracin did not affect its activity. In-silico analysis shows the five amino acids changes in the protein sequence regarding to the consensus sequence of PDIs, have a positive impact toward the protein thermal stability. This was further confirmed by molecular dynamics simulations. By considering the overall results, the enzyme might be a potential candidate for applications in the respective industries.
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Affiliation(s)
- Milad Lagzian
- Department of Biology, Faculty of Science, University of Sistan and Baluchestan, Zahedan, Iran.
| | - Ali Shahraki
- Department of Biology, Faculty of Science, University of Sistan and Baluchestan, Zahedan, Iran
| | - Mahdiyeh Besharatian
- Department of Biology, Faculty of Science, University of Sistan and Baluchestan, Zahedan, Iran
| | - Ahmad Asoodeh
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
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47
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Lee SF, Davey L. Disulfide Bonds: A Key Modification in Bacterial Extracytoplasmic Proteins. J Dent Res 2017; 96:1465-1473. [PMID: 28797211 DOI: 10.1177/0022034517725059] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Disulfide bonds are a common posttranslational modification that contributes to the folding and stability of extracytoplasmic proteins. Almost all organisms, from eukaryotes to prokaryotes, have evolved enzymes to make and break these bonds. Accurate and efficient disulfide bond formation can be vital for protein function; therefore, the enzymes that catalyze disulfide bond formation are involved in multiple biological processes. Recent advances clearly show that oral bacteria also have the ability to from disulfide bonds, and this ability has an effect on a range of dental plaque-related phenotypes. In the gram-positive Streptococcus gordonii, the ability to form disulfide bonds affected autolysis, extracellular DNA release, biofilm formation, genetic competence, and bacteriocin production. In Actinomyces oris, disulfide bond formation is needed for pilus assembly, coaggregation, and biofilm formation. In other gram-positive bacteria, such as Enterococcus faecalis, disulfide bonds are formed in secreted bacteriocins and required for activity. In these oral bacteria, the enzymes that catalyze the disulfide bonds are quite diverse and share little sequence homology, but all contain a CXXC catalytic active site motif and a conserved C-terminal cis-proline, signature features of a thiol-disulfide oxidoreductase. Emerging evidence also indicates that gram-negative oral bacteria, such as Porphyromonas gingivalis and Tannerella forsythia, use disulfide bonds to stabilize their outer membrane porin proteins. Bioinformatic screens reveal that these gram-negative bacteria carry genes coding for thiol-disulfide oxidoreductases in their genomes. In conclusion, disulfide bond formation in oral bacteria is an emerging field, and the ability to form disulfide bonds plays an important role in dental plaque formation and fitness for the bacteria.
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Affiliation(s)
- S F Lee
- 1 Department of Microbiology and Immunology, Dalhousie University, Halifax, NS, Canada.,2 Canadian Center for Vaccinology, Dalhousie University and the IWK Health Centre, Halifax, NS, Canada.,3 Department of Pediatrics, Faculty of Medicine, Dalhousie University and the IWK Health Centre, Halifax, NS, Canada.,4 Department of Applied Oral Sciences, Faculty of Dentistry, Dalhousie University, Halifax, NS, Canada
| | - L Davey
- 1 Department of Microbiology and Immunology, Dalhousie University, Halifax, NS, Canada.,2 Canadian Center for Vaccinology, Dalhousie University and the IWK Health Centre, Halifax, NS, Canada.,Current address: Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
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Abstract
Cysteine thiols are among the most reactive functional groups in proteins, and their pairing in disulfide linkages is a common post-translational modification in proteins entering the secretory pathway. This modest amino acid alteration, the mere removal of a pair of hydrogen atoms from juxtaposed cysteine residues, contrasts with the substantial changes that characterize most other post-translational reactions. However, the wide variety of proteins that contain disulfides, the profound impact of cross-linking on the behavior of the protein polymer, the numerous and diverse players in intracellular pathways for disulfide formation, and the distinct biological settings in which disulfide bond formation can take place belie the simplicity of the process. Here we lay the groundwork for appreciating the mechanisms and consequences of disulfide bond formation in vivo by reviewing chemical principles underlying cysteine pairing and oxidation. We then show how enzymes tune redox-active cofactors and recruit oxidants to improve the specificity and efficiency of disulfide formation. Finally, we discuss disulfide bond formation in a cellular context and identify important principles that contribute to productive thiol oxidation in complex, crowded, dynamic environments.
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Affiliation(s)
- Deborah Fass
- Department of Structural Biology, Weizmann Institute of Science , Rehovot 7610001, Israel
| | - Colin Thorpe
- Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States
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Chen L, Wang M, Huang L, Zhang Z, Liu F, Lu G. XC_0531 encodes a c-type cytochrome biogenesis protein and is required for pathogenesis in Xanthomonas campestris pv. campestris. BMC Microbiol 2017; 17:142. [PMID: 28655353 PMCID: PMC5488342 DOI: 10.1186/s12866-017-1056-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 06/21/2017] [Indexed: 11/13/2022] Open
Abstract
Background The phytopathogenic Xanthomonas campestris pv.campestris is a gram-negative bacterium and the causal agent of black-rot disease of cruciferous crops. Many gram-negative bacteria possess a family of proteins, called Dsbs, which are involved in disulfide bond formation in certain periplasmic proteins. In our preliminary screening of the virulence to the plants we identified that gene XC_0531 which annotated gene dsbD of Xanthomonas campestris pv. campestris (Xcc) is related to the virulence to the host plants. Results Here, we found XC_0531 encoded a DsbD like protein. Its deletion is sensitive to DTT and copper, decreased accumulation of free thiols in periplasm. Its deletion also affected heme synthesis, position of Soret band and the production of peak c550. This suggests that XC_0531 is related to c-type cytochromes biogenesis. XC_0531 mutation decreased the utilization of different carbon sources (such as galactose, xylose, maltose, saccharose and glucose), reduced extracellular polysaccharide (EPS) production, decreased extracellular enzyme activities (protease, cellulose and amylase), slowed down growth rate of Xcc and weakened virulence to the plants. These results suggest that these phenotypes caused by XC_0531 mutation is possibly due to deficient biosynthesis of c-type cytochromes in respiration chain and the formation of disulfide bonds. Our work confirmed the function of XC_0531 and provide theory basis for scientists working on molecular mechanisms of cytochrome c biogenesis, pathogenesis of Xcc, development of EPS commercial values and protecting plant from black rot. Conclusion We confirmed the function of gene XC_0531, which encodes a DsbD like protein, a protein correlated with c-type cytochrome biogenesis. This gene is related to the virulence to plants by affecting funtion of cytochromes c and probably disulfide bonds modification of proteins in type II secretion system (T2SS). Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-1056-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lei Chen
- State Key Laboratory for Conservation and State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, The Key Laboratory ofMinistry of Education for Microbial and Plant Genetic Engineering, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China.,Key Laboratory of Coastal Biology and Biological Resources Utilization, Yantai Institute of Coastal Zone Research, Yantai, China
| | - Mingpeng Wang
- Key Laboratory of Coastal Biology and Biological Resources Utilization, Yantai Institute of Coastal Zone Research, Yantai, China
| | - Li Huang
- State Key Laboratory for Conservation and State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, The Key Laboratory ofMinistry of Education for Microbial and Plant Genetic Engineering, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China
| | - Zhaojie Zhang
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA
| | - Fanghua Liu
- Key Laboratory of Coastal Biology and Biological Resources Utilization, Yantai Institute of Coastal Zone Research, Yantai, China
| | - Guangtao Lu
- State Key Laboratory for Conservation and State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, The Key Laboratory ofMinistry of Education for Microbial and Plant Genetic Engineering, Guangxi University, 100 Daxue Road, Nanning, Guangxi, 530004, China.
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Movement protein of Apple chlorotic leaf spot virus is genetically unstable and negatively regulated by Ribonuclease E in E. coli. Sci Rep 2017; 7:2133. [PMID: 28522867 PMCID: PMC5437062 DOI: 10.1038/s41598-017-02375-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 04/10/2017] [Indexed: 12/03/2022] Open
Abstract
Movement protein (MP) of Apple chlorotic leaf spot virus (ACLSV) belongs to “30 K” superfamily of proteins and members of this family are known to show a wide array of functions. In the present study this gene was found to be genetically unstable in E. coli when transformed DH5α cells were grown at 28 °C and 37 °C. However, genetic instability was not encountered at 20 °C. Heterologous over expression failed despite the use of different transcriptional promoters and translational fusion constructs. Total cell lysate when subjected to western blotting using anti-ACLSV MP antibodies, showed degradation/cleavage of the expressed full-length protein. This degradation pointed at severe proteolysis or instability of the corresponding mRNA. Predicted secondary structure analysis of the transcript revealed a potential cleavage site for an endoribonuclease (RNase E) of E. coli. The negating effect of RNase E on transcript stability and expression was confirmed by northern blotting and quantitative RT-PCR of the RNA extracted from RNase E temperature sensitive mutant (strain N3431). The five fold accumulation of transcripts at non-permissive temperature (43 °C) suggests the direct role of RNase E in regulating the expression of ACLSV MP in E. coli.
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