1
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Wang X, Nyenhuis SB, Bernstein HD. The translocation assembly module (TAM) catalyzes the assembly of bacterial outer membrane proteins in vitro. Nat Commun 2024; 15:7246. [PMID: 39174534 PMCID: PMC11341756 DOI: 10.1038/s41467-024-51628-8] [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: 10/20/2023] [Accepted: 08/12/2024] [Indexed: 08/24/2024] Open
Abstract
The translocation and assembly module (TAM) has been proposed to play a crucial role in the assembly of a small subset of outer membrane proteins (OMPs) in Proteobacteria based on experiments conducted in vivo using tamA and tamB mutant strains and in vitro using biophysical methods. TAM consists of an OMP (TamA) and a periplasmic protein that is anchored to the inner membrane by a single α helix (TamB). Here we examine the function of the purified E. coli complex in vitro after reconstituting it into proteoliposomes. We find that TAM catalyzes the assembly of four model OMPs nearly as well as the β-barrel assembly machine (BAM), a universal heterooligomer that contains a TamA homolog (BamA) and that catalyzes the assembly of almost all E. coli OMPs. Consistent with previous results, both TamA and TamB are required for significant TAM activity. Our study provides direct evidence that TAM can function as an independent OMP insertase and describes a new method to gain insights into TAM function.
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Affiliation(s)
- Xu Wang
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Sarah B Nyenhuis
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Harris D Bernstein
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA.
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2
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Devlin T, Fleming KG. A team of chaperones play to win in the bacterial periplasm. Trends Biochem Sci 2024; 49:667-680. [PMID: 38677921 DOI: 10.1016/j.tibs.2024.03.015] [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: 12/18/2023] [Revised: 03/14/2024] [Accepted: 03/22/2024] [Indexed: 04/29/2024]
Abstract
The survival and virulence of Gram-negative bacteria require proper biogenesis and maintenance of the outer membrane (OM), which is densely packed with β-barrel OM proteins (OMPs). Before reaching the OM, precursor unfolded OMPs (uOMPs) must cross the whole cell envelope. A network of periplasmic chaperones and proteases maintains unfolded but folding-competent conformations of these membrane proteins in the aqueous periplasm while simultaneously preventing off-pathway aggregation. These periplasmic proteins utilize different strategies, including conformational heterogeneity, oligomerization, multivalency, and kinetic partitioning, to perform and regulate their functions. Redundant and unique characteristics of the individual periplasmic players synergize to create a protein quality control team capable responding to changing environmental stresses.
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Affiliation(s)
- Taylor Devlin
- Thomas C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Karen G Fleming
- Thomas C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA.
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3
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Wang X, Nyenhuis SB, Bernstein HD. The translocation assembly module (TAM) catalyzes the assembly of bacterial outer membrane proteins in vitro. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.20.599893. [PMID: 39372782 PMCID: PMC11451606 DOI: 10.1101/2024.06.20.599893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/08/2024]
Abstract
The bacterial translocation assembly module (TAM) contains an outer membrane protein (OMP) (TamA) and an elongated periplasmic protein that is anchored to the inner membrane by a single α helix (TamB). TAM has been proposed to play a critical role in the assembly of a small subset of OMPs produced by Proteobacteria based on experiments conducted in vivo using tamA and/or tamB deletion or mutant strains and in vitro using biophysical methods. Recent genetic experiments, however, have strongly suggested that TAM promotes phospholipid homeostasis. To test the idea that TAM catalyzes OMP assembly directly, we examined the function of the purified E. coli complex in vitro after reconstituting it into proteoliposomes. Remarkably, we find that TAM catalyzes the assembly of four model OMPs nearly as well as the β-barrel assembly machinery (BAM), a universal heterooligomer that contains a TamA homolog (BamA) and that catalyzes the assembly of almost all E. coli OMPs. Consistent with previous results, both TamA and TamB are required for significant TAM activity. Our results provide strong evidence that although their peripheral subunits are unrelated, both BAM and TAM function as independent OMP insertases. Furthermore, our study describes a new method to gain insights into TAM function.
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Affiliation(s)
- Xu Wang
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892 USA
| | - Sarah B. Nyenhuis
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892 USA
| | - Harris D. Bernstein
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892 USA
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4
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Harkness RW, Zhao H, Toyama Y, Schuck P, Kay LE. Exploring Host-Guest Interactions within a 600 kDa DegP Protease Cage Complex Using Hydrodynamics Measurements and Methyl-TROSY NMR. J Am Chem Soc 2024; 146:8242-8259. [PMID: 38477967 DOI: 10.1021/jacs.3c13247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
The DegP protease-chaperone operates within the periplasm of Gram-negative bacteria, where it assists in the regulation of protein homeostasis, promotes virulence, and is essential to survival under stress. To carry out these tasks, DegP forms a network of preorganized apo oligomers that facilitate the capture of substrates within distributions of cage-like complexes which expand to encapsulate clients of various sizes. Although the architectures of DegP cage complexes are well understood, little is known about the structures, dynamics, and interactions of client proteins within DegP cages and the relationship between client structural dynamics and function. Here, we probe host-guest interactions within a 600 kDa DegP cage complex throughout the DegP activation cycle using a model α-helical client protein through a combination of hydrodynamics measurements, methyl-transverse relaxation optimized spectroscopy-based solution nuclear magnetic resonance studies, and proteolytic activity assays. We find that in the presence of the client, DegP cages assemble cooperatively with few intermediates. Our data further show that the N-terminal half of the bound client, which projects into the interior of the cages, is predominantly unfolded and flexible, and exchanges between multiple conformational states over a wide range of time scales. Finally, we show that a concerted structural transition of the protease domains of DegP occurs upon client engagement, leading to activation. Together, our findings support a model of DegP as a highly cooperative and dynamic molecular machine that stabilizes unfolded states of clients, primarily via interactions with their C-termini, giving rise to efficient cleavage.
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Affiliation(s)
- Robert W Harkness
- Department of Biochemistry, University of Toronto, Toronto M5S 1A8, Canada
- Department of Molecular Genetics, University of Toronto, Toronto M5S 1A8, Canada
- Department of Chemistry, University of Toronto, Toronto M5S 3H6, Canada
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto M5G 0A4, Canada
| | - Huaying Zhao
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Yuki Toyama
- Department of Biochemistry, University of Toronto, Toronto M5S 1A8, Canada
- Department of Molecular Genetics, University of Toronto, Toronto M5S 1A8, Canada
- Department of Chemistry, University of Toronto, Toronto M5S 3H6, Canada
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto M5G 0A4, Canada
| | - Peter Schuck
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Lewis E Kay
- Department of Biochemistry, University of Toronto, Toronto M5S 1A8, Canada
- Department of Molecular Genetics, University of Toronto, Toronto M5S 1A8, Canada
- Department of Chemistry, University of Toronto, Toronto M5S 3H6, Canada
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto M5G 0A4, Canada
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Hariharan P, Shi Y, Katsube S, Willibal K, Burrows ND, Mitchell P, Bakhtiiari A, Stanfield S, Pardon E, Kaback HR, Liang R, Steyaert J, Viner R, Guan L. Mobile barrier mechanisms for Na +-coupled symport in an MFS sugar transporter. eLife 2024; 12:RP92462. [PMID: 38381130 PMCID: PMC10942615 DOI: 10.7554/elife.92462] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2024] Open
Abstract
While many 3D structures of cation-coupled transporters have been determined, the mechanistic details governing the obligatory coupling and functional regulations still remain elusive. The bacterial melibiose transporter (MelB) is a prototype of major facilitator superfamily transporters. With a conformation-selective nanobody, we determined a low-sugar affinity inward-facing Na+-bound cryoEM structure. The available outward-facing sugar-bound structures showed that the N- and C-terminal residues of the inner barrier contribute to the sugar selectivity. The inward-open conformation shows that the sugar selectivity pocket is also broken when the inner barrier is broken. Isothermal titration calorimetry measurements revealed that this inward-facing conformation trapped by this nanobody exhibited a greatly decreased sugar-binding affinity, suggesting the mechanisms for substrate intracellular release and accumulation. While the inner/outer barrier shift directly regulates the sugar-binding affinity, it has little or no effect on the cation binding, which is supported by molecular dynamics simulations. Furthermore, the hydron/deuterium exchange mass spectrometry analyses allowed us to identify dynamic regions; some regions are involved in the functionally important inner barrier-specific salt-bridge network, which indicates their critical roles in the barrier switching mechanisms for transport. These complementary results provided structural and dynamic insights into the mobile barrier mechanism for cation-coupled symport.
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Affiliation(s)
- Parameswaran Hariharan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, School of MedicineLubbockUnited States
| | - Yuqi Shi
- Thermo Fisher ScientificSan JoseUnited States
| | - Satoshi Katsube
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, School of MedicineLubbockUnited States
| | - Katleen Willibal
- VIB-VUB Center for Structural Biology, VIB, Pleinlaan 2BrusselsBelgium
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2BrusselsBelgium
| | - Nathan D Burrows
- Division of CryoEM and Bioimaging, Stanford Synchrotron Radiation Light Source, SLAC National Accelerator LaboratoryMenlo ParkUnited States
| | - Patrick Mitchell
- Division of CryoEM and Bioimaging, Stanford Synchrotron Radiation Light Source, SLAC National Accelerator LaboratoryMenlo ParkUnited States
| | | | - Samantha Stanfield
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, School of MedicineLubbockUnited States
| | - Els Pardon
- VIB-VUB Center for Structural Biology, VIB, Pleinlaan 2BrusselsBelgium
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2BrusselsBelgium
| | - H Ronald Kaback
- Department of Physiology, University of California, Los AngelesLos AngelesUnited States
| | - Ruibin Liang
- Department of Chemistry and Biochemistry, Texas Tech UniversityLubbockUnited States
| | - Jan Steyaert
- VIB-VUB Center for Structural Biology, VIB, Pleinlaan 2BrusselsBelgium
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2BrusselsBelgium
| | - Rosa Viner
- Thermo Fisher ScientificSan JoseUnited States
| | - Lan Guan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, School of MedicineLubbockUnited States
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Luo H, Qu X, Deng X, He L, Wu Y, Liu Y, He D, Yin J, Wang B, Gan F, Tang B, Tang XF. HtrAs are essential for the survival of the haloarchaeon Natrinema gari J7-2 in response to heat, high salinity, and toxic substances. Appl Environ Microbiol 2024; 90:e0204823. [PMID: 38289131 PMCID: PMC10880668 DOI: 10.1128/aem.02048-23] [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: 11/13/2023] [Accepted: 12/24/2023] [Indexed: 02/22/2024] Open
Abstract
Bacterial and eukaryotic HtrAs can act as an extracytoplasmic protein quality control (PQC) system to help cells survive in stress conditions, but the functions of archaeal HtrAs remain unknown. Particularly, haloarchaea route most secretory proteins to the Tat pathway, enabling them to fold properly in well-controlled cytoplasm with cytosolic PQC systems before secretion. It is unclear whether HtrAs are required for haloarchaeal survival and stress response. The haloarchaeon Natrinema gari J7-2 encodes three Tat signal peptide-bearing HtrAs (NgHtrA, NgHtrB, and NgHtrC), and the signal peptides of NgHtrA and NgHtrC contain a lipobox. Here, the in vitro analysis reveals that the three HtrAs show different profiles of temperature-, salinity-, and metal ion-dependent proteolytic activities and could exhibit chaperone-like activities to prevent the aggregation of reduced lysozyme when their proteolytic activities are inhibited at low temperatures or the active site is disrupted. The gene deletion and complementation assays reveal that NgHtrA and NgHtrC are essential for the survival of strain J7-2 at elevated temperature and/or high salinity and contribute to the resistance of this haloarchaeon to zinc and inhibitory substances generated from tryptone. Mutational analysis shows that the lipobox mediates membrane anchoring of NgHtrA or NgHtrC, and both the membrane-anchored and free extracellular forms of the two enzymes are involved in the stress resistance of strain J7-2, depending on the stress conditions. Deletion of the gene encoding NgHtrB in strain J7-2 causes no obvious growth defect, but NgHtrB can functionally substitute for NgHtrA or NgHtrC under some conditions.IMPORTANCEHtrA-mediated protein quality control plays an important role in the removal of aberrant proteins in the extracytoplasmic space of living cells, and the action mechanisms of HtrAs have been extensively studied in bacteria and eukaryotes; however, information about the function of archaeal HtrAs is scarce. Our results demonstrate that three HtrAs of the haloarchaeon Natrinema gari J7-2 possess both proteolytic and chaperone-like activities, confirming that the bifunctional nature of HtrAs is conserved across all three domains of life. Moreover, we found that NgHtrA and NgHtrC are essential for the survival of strain J7-2 under stress conditions, while NgHtrB can serve as a substitute for the other two HtrAs under certain circumstances. This study provides the first biochemical and genetic evidence of the importance of HtrAs for the survival of haloarchaea in response to stresses.
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Affiliation(s)
- Hongyi Luo
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiaoyi Qu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xi Deng
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Liping He
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yi Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yang Liu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Dan He
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jing Yin
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Bingxue Wang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Fei Gan
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
- Cooperative Innovation Center of Industrial Fermentation, Ministry of Education and Hubei Province, Wuhan, China
| | - Bing Tang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- Cooperative Innovation Center of Industrial Fermentation, Ministry of Education and Hubei Province, Wuhan, China
| | - Xiao-Feng Tang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
- Cooperative Innovation Center of Industrial Fermentation, Ministry of Education and Hubei Province, Wuhan, China
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George JL, Agbavor C, Cabo LF, Cahoon LA. Streptococcus pneumoniae secretion chaperones PrsA, SlrA, and HtrA are required for competence, antibiotic resistance, colonization, and invasive disease. Infect Immun 2024; 92:e0049023. [PMID: 38226817 PMCID: PMC10863415 DOI: 10.1128/iai.00490-23] [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: 11/27/2023] [Accepted: 12/19/2023] [Indexed: 01/17/2024] Open
Abstract
Streptococcus pneumoniae is a Gram-positive bacterium and a significant health threat with the populations most at risk being children, the elderly, and the immuno-compromised. To colonize and transition into an invasive infectious organism, S. pneumoniae secretes virulence factors that are translocated across the bacterial membrane and destined for surface exposure, attachment to the cell wall, or secretion into the host. The surface exposed protein chaperones PrsA, SlrA, and HtrA facilitate S. pneumoniae protein secretion; however, the distinct roles contributed by each of these secretion chaperones have not been well defined. Tandem Mass-Tagged Mass Spectrometry and virulence, adhesion, competence, and cell wall integrity assays were used to interrogate the individual and collective contributions of PrsA, SlrA, and HtrA to multiple aspects of S. pneumoniae physiology and virulence. PrsA, SlrA, and HtrA were found to play critical roles in S. pneumoniae host cell infection and competence, and the absence of each of these secretion chaperones significantly altered the S. pneumoniae secretome in distinct ways. PrsA and SlrA were additionally found to contribute to cell wall assembly and resistance to cell wall-active antimicrobials and were important for enabling S. pneumoniae host cell adhesion during colonization and invasive infection. These findings serve to further illustrate the pivotal contributions of PrsA, SlrA, and HtrA to S. pneumoniae protein secretion and virulence.
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Affiliation(s)
- Jada L. George
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Charles Agbavor
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Leah F. Cabo
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Laty A. Cahoon
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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8
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Su J, Jiao Q, Jia T, Hu X. The photosystem-II repair cycle: updates and open questions. PLANTA 2023; 259:20. [PMID: 38091081 DOI: 10.1007/s00425-023-04295-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 11/15/2023] [Indexed: 12/18/2023]
Abstract
MAIN CONCLUSION The photosystem-II (PSII) repair cycle is essential for the maintenance of photosynthesis in plants. A number of novel findings have illuminated the regulatory mechanisms of the PSII repair cycle. Photosystem II (PSII) is a large pigment-protein complex embedded in the thylakoid membrane. It plays a vital role in photosynthesis by absorbing light energy, splitting water, releasing molecular oxygen, and transferring electrons for plastoquinone reduction. However, PSII, especially the PsbA (D1) core subunit, is highly susceptible to oxidative damage. To prevent irreversible damage, plants have developed a repair cycle. The main objective of the PSII repair cycle is the degradation of photodamaged D1 and insertion of newly synthesized D1 into the PSII complex. While many factors are known to be involved in PSII repair, the exact mechanism is still under investigation. In this review, we discuss the primary steps of PSII repair, focusing on the proteolytic degradation of photodamaged D1 and the factors involved.
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Affiliation(s)
- Jinling Su
- International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
- Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Qingsong Jiao
- International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
- Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China
| | - Ting Jia
- International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.
- Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China.
| | - Xueyun Hu
- International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China.
- Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou, 225009, China.
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, 225009, China.
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9
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Hariharan P, Shi Y, Katsube S, Willibal K, Burrows ND, Mitchell P, Bakhtiiari A, Stanfield S, Pardon E, Kaback HR, Liang R, Steyaert J, Viner R, Guan L. Mobile barrier mechanisms for Na +-coupled symport in an MFS sugar transporter. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.18.558283. [PMID: 37790566 PMCID: PMC10542114 DOI: 10.1101/2023.09.18.558283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
While many 3D structures of cation-coupled transporters have been determined, the mechanistic details governing the obligatory coupling and functional regulations still remain elusive. The bacterial melibiose transporter (MelB) is a prototype of the Na+-coupled major facilitator superfamily transporters. With a conformational nanobody (Nb), we determined a low-sugar affinity inward-facing Na+-bound cryoEM structure. Collectively with the available outward-facing sugar-bound structures, both the outer and inner barriers were localized. The N- and C-terminal residues of the inner barrier contribute to the sugar selectivity pocket. When the inner barrier is broken as shown in the inward-open conformation, the sugar selectivity pocket is also broken. The binding assays by isothermal titration calorimetry revealed that this inward-facing conformation trapped by the conformation-selective Nb exhibited a greatly decreased sugar-binding affinity, suggesting the mechanisms for the substrate intracellular release and accumulation. While the inner/outer barrier shift directly regulates the sugar-binding affinity, it has little or no effect on the cation binding, which is also supported by molecular dynamics simulations. Furthermore, the use of this Nb in combination with the hydron/deuterium exchange mass spectrometry allowed us to identify dynamic regions; some regions are involved in the functionally important inner barrier-specific salt-bridge network, which indicates their critical roles in the barrier switching mechanisms for transport. These complementary results provided structural and dynamic insights into the mobile barrier mechanism for cation-coupled symport.
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Affiliation(s)
- Parameswaran Hariharan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, TX 79424, USA
| | - Yuqi Shi
- Thermo Fisher Scientific, San Jose, CA 95134, USA
| | - Satoshi Katsube
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, TX 79424, USA
| | | | - Nathan D. Burrows
- Division of CryoEM and Bioimaging, Stanford Synchrotron Radiation Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Patrick Mitchell
- Division of CryoEM and Bioimaging, Stanford Synchrotron Radiation Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | | | - Samantha Stanfield
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, TX 79424, USA
| | - Els Pardon
- VIB-VUB Center for Structural Biology, 1050 Brussel, Belgium
| | - H. Ronald Kaback
- Department of Physiology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Ruibin Liang
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA
| | - Jan Steyaert
- VIB-VUB Center for Structural Biology, 1050 Brussel, Belgium
| | - Rosa Viner
- Thermo Fisher Scientific, San Jose, CA 95134, USA
| | - Lan Guan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, TX 79424, USA
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10
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Maziero M, Lane D, Polard P, Bergé M. Fever-like temperature bursts promote competence development via an HtrA-dependent pathway in Streptococcus pneumoniae. PLoS Genet 2023; 19:e1010946. [PMID: 37699047 PMCID: PMC10516426 DOI: 10.1371/journal.pgen.1010946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 09/22/2023] [Accepted: 08/30/2023] [Indexed: 09/14/2023] Open
Abstract
Streptococcus pneumoniae (the pneumococcus) is well known for its ability to develop competence for natural DNA transformation. Competence development is regulated by an autocatalytic loop driven by variations in the basal level of transcription of the comCDE and comAB operons. These genes are part of the early gene regulon that controls expression of the late competence genes known to encode the apparatus of transformation. Several stressful conditions are known to promote competence development, although the induction pathways are remain poorly understood. Here we demonstrate that transient temperature elevation induces an immediate increase in the basal expression level of the comCDE operon and early genes that, in turn, stimulates its full induction, including that of the late competence regulon. This thermal regulation depends on the HtrA chaperone/protease and its proteolytic activity. We find that other competence induction stimulus, like norfloxacin, is not conveyed by the HtrA-dependent pathway. This finding strongly suggests that competence can be induced by at least two independent pathways and thus reinforces the view that competence is a general stress response system in the pneumococcus.
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Affiliation(s)
- Mickaël Maziero
- Laboratoire de Microbiologie et Génétique Moléculaires (LMGM), UMR5100, Centre de Biologie Intégrative (CBI), Centre Nationale de la Recherche Scientifique (CNRS), Toulouse, France
- Université Paul Sabatier (Toulouse III), Toulouse, France
| | - David Lane
- Laboratoire de Microbiologie et Génétique Moléculaires (LMGM), UMR5100, Centre de Biologie Intégrative (CBI), Centre Nationale de la Recherche Scientifique (CNRS), Toulouse, France
- Université Paul Sabatier (Toulouse III), Toulouse, France
| | - Patrice Polard
- Laboratoire de Microbiologie et Génétique Moléculaires (LMGM), UMR5100, Centre de Biologie Intégrative (CBI), Centre Nationale de la Recherche Scientifique (CNRS), Toulouse, France
- Université Paul Sabatier (Toulouse III), Toulouse, France
| | - Mathieu Bergé
- Laboratoire de Microbiologie et Génétique Moléculaires (LMGM), UMR5100, Centre de Biologie Intégrative (CBI), Centre Nationale de la Recherche Scientifique (CNRS), Toulouse, France
- Université Paul Sabatier (Toulouse III), Toulouse, France
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Katsube S, Willibal K, Vemulapally S, Hariharan P, Tikhonova E, Pardon E, Kaback HR, Steyaert J, Guan L. In vivo and in vitro characterizations of melibiose permease (MelB) conformation-dependent nanobodies reveal sugar-binding mechanisms. J Biol Chem 2023; 299:104967. [PMID: 37380079 PMCID: PMC10374971 DOI: 10.1016/j.jbc.2023.104967] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 06/13/2023] [Accepted: 06/19/2023] [Indexed: 06/30/2023] Open
Abstract
Salmonella enterica serovar Typhimurium melibiose permease (MelBSt) is a prototype of the Na+-coupled major facilitator superfamily transporters, which are important for the cellular uptake of molecules including sugars and small drugs. Although the symport mechanisms have been well-studied, mechanisms of substrate binding and translocation remain enigmatic. We have previously determined the sugar-binding site of outward-facing MelBSt by crystallography. To obtain other key kinetic states, here we raised camelid single-domain nanobodies (Nbs) and carried out a screening against the WT MelBSt under 4 ligand conditions. We applied an in vivo cAMP-dependent two-hybrid assay to detect interactions of Nbs with MelBSt and melibiose transport assays to determine the effects on MelBSt functions. We found that all selected Nbs showed partial to complete inhibitions of MelBSt transport activities, confirming their intracellular interactions. A group of Nbs (714, 725, and 733) was purified, and isothermal titration calorimetry measurements showed that their binding affinities were significantly inhibited by the substrate melibiose. When titrating melibiose to the MelBSt/Nb complexes, Nb also inhibited the sugar-binding. However, the Nb733/MelBSt complex retained binding to the coupling cation Na+ and also to the regulatory enzyme EIIAGlc of the glucose-specific phosphoenolpyruvate/sugar phosphotransferase system. Further, EIIAGlc/MelBSt complex also retained binding to Nb733 and formed a stable supercomplex. All data indicated that MelBSt trapped by Nbs retained its physiological functions and the trapped conformation is similar to that bound by the physiological regulator EIIAGlc. Therefore, these conformational Nbs can be useful tools for further structural, functional, and conformational analyses.
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Affiliation(s)
- Satoshi Katsube
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Katleen Willibal
- VIB Center for Structural Biology Research, VIB, Brussel, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel, Brussel, Belgium
| | - Sangama Vemulapally
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Parameswaran Hariharan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Elena Tikhonova
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
| | - Els Pardon
- VIB Center for Structural Biology Research, VIB, Brussel, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel, Brussel, Belgium
| | - H Ronald Kaback
- Department of Physiology and Department of Microbiology, Immunology, and Molecular Genetics, Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California, USA
| | - Jan Steyaert
- VIB Center for Structural Biology Research, VIB, Brussel, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel, Brussel, Belgium
| | - Lan Guan
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA.
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12
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Kadeřábková N, Mahmood AJS, Furniss RCD, Mavridou DAI. Making a chink in their armor: Current and next-generation antimicrobial strategies against the bacterial cell envelope. Adv Microb Physiol 2023; 83:221-307. [PMID: 37507160 PMCID: PMC10517717 DOI: 10.1016/bs.ampbs.2023.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
Gram-negative bacteria are uniquely equipped to defeat antibiotics. Their outermost layer, the cell envelope, is a natural permeability barrier that contains an array of resistance proteins capable of neutralizing most existing antimicrobials. As a result, its presence creates a major obstacle for the treatment of resistant infections and for the development of new antibiotics. Despite this seemingly impenetrable armor, in-depth understanding of the cell envelope, including structural, functional and systems biology insights, has promoted efforts to target it that can ultimately lead to the generation of new antibacterial therapies. In this article, we broadly overview the biology of the cell envelope and highlight attempts and successes in generating inhibitors that impair its function or biogenesis. We argue that the very structure that has hampered antibiotic discovery for decades has untapped potential for the design of novel next-generation therapeutics against bacterial pathogens.
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Affiliation(s)
- Nikol Kadeřábková
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States
| | - Ayesha J S Mahmood
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States
| | - R Christopher D Furniss
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Despoina A I Mavridou
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States; John Ring LaMontagne Center for Infectious Diseases, The University of Texas at Austin, Austin, TX, United States.
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13
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Malhotra H, Saha BK, Phale PS. Development of efficient modules for recombinant protein expression and periplasmic localiszation in Pseudomonas bharatica CSV86 T. Protein Expr Purif 2023; 210:106310. [PMID: 37211150 DOI: 10.1016/j.pep.2023.106310] [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: 03/23/2023] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 05/23/2023]
Abstract
Escherichia coli has been widely employed as a host for heterologous protein expression. However, due to certain limitations, alternative hosts like Pseudomonas, Lactococcus and Bacillus are being explored. Pseudomonas bharatica CSV86T, a novel soil isolate, preferentially degrades wide range of aromatics over simple carbon sources like glucose and glycerol. Strain also possesses advantageous eco-physiological traits, making it an ideal host for engineering xenobiotic degradation pathways, which necessitates the development of heterologous expression systems. Based on the efficient growth, short lag-phase and rapid metabolism of naphthalene, Pnah and Psal promoters (regulated by NahR) were selected for expression. Pnah was found to be strong and leaky as compared to Psal, using 1-naphthol 2-hydroxylase (1NH, ∼66 kDa) as reporter gene in strain CSV86T. The Carbaryl hydrolase (CH, ∼72kDa) from Pseudomonas sp. C5pp was expressed under Pnah in strain CSV86T and could successfully be translocated to the periplasm due to the presence of the Tmd + Sp sequence. The recombinant CH was purified from the periplasmic fraction and the kinetic characteristics were found to be similar to the native protein from strain C5pp. These results potentiate the suitability of P. bharatica CSV86T as a desirable host, while Pnah and the Tmd + Sp can be employed for overexpression and periplasmic localisation, respectively. Such tools find application in heterologous protein expression and metabolic engineering applications.
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Affiliation(s)
- Harshit Malhotra
- Department of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Powai, Mumbai, 400076, India
| | - Braja Kishor Saha
- Department of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Powai, Mumbai, 400076, India
| | - Prashant S Phale
- Department of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Powai, Mumbai, 400076, India.
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14
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Xu Q, Guo M, Yu F. β-Barrel Assembly Machinery (BAM) Complex as Novel Antibacterial Drug Target. Molecules 2023; 28:molecules28093758. [PMID: 37175168 PMCID: PMC10180388 DOI: 10.3390/molecules28093758] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/05/2023] [Accepted: 03/08/2023] [Indexed: 05/15/2023] Open
Abstract
The outer membrane of Gram-negative bacteria is closely related to the pathogenicity and drug resistance of bacteria. Outer membrane proteins (OMPs) are a class of proteins with important biological functions on the outer membrane. The β-barrel assembly machinery (BAM) complex plays a key role in OMP biogenesis, which ensures that the OMP is inserted into the outer membrane in a correct folding manner and performs nutrient uptake, antibiotic resistance, cell adhesion, cell signaling, and maintenance of membrane stability and other functions. The BAM complex is highly conserved among Gram-negative bacteria. The abnormality of the BAM complex will lead to the obstruction of OMP folding, affect the function of the outer membrane, and eventually lead to bacterial death. In view of the important role of the BAM complex in OMP biogenesis, the BAM complex has become an attractive target for the development of new antibacterial drugs against Gram-negative bacteria. Here, we summarize the structure and function of the BAM complex and review the latest research progress of antibacterial drugs targeting BAM in order to provide a new perspective for the development of antibiotics.
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Affiliation(s)
- Qian Xu
- Laboratory of Molecular Pathology, Department of Pathology, Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, China
| | - Min Guo
- Allergy Clinic, Zibo Central Hospital, Zibo 255000, China
| | - Feiyuan Yu
- Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
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15
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Zhang X, Lin Y, Xu X, Wen S, Wang Z, Gu J, He Q, Cai X. HtrA is involved in stress response and adhesion in Glaesserella parasuis serovar 5 strain Nagasaki. Vet Microbiol 2023; 282:109748. [PMID: 37120968 DOI: 10.1016/j.vetmic.2023.109748] [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: 08/18/2022] [Revised: 02/28/2023] [Accepted: 04/14/2023] [Indexed: 05/02/2023]
Abstract
Glaesserella parasuis is an important pathogen that causes fibrinous polyserositis, peritonitis and meningitis in pigs, leading to considerable economic losses to the swine industry worldwide. It is well established that the serine protease HtrA is closely associated with bacterial virulence, but the role of HtrA in G. parasuis pathogenesis remains largely unknown. To characterize the function of the htrA gene in G. parasuis, a ΔhtrA mutant was constructed. We found that the ΔhtrA mutant showed significant growth inhibition under heat shock and alkaline stress conditions, indicating HtrA is involved in stress tolerance and survival of G. parasuis. In addition, deletion of htrA gene resulted in decreased adherence to PIEC and PK-15 cells and increased phagocytic resistance to 3D4/2 macrophages, suggesting that htrA is essential for adherence of G. parasuis. Scanning electron microscopy revealed morphological surface changes of the ΔhtrA mutant, and transcription analysis confirmed that a number of adhesion-associated genes are downregulated, which corroborated the aforementioned phenomenon. Furthermore, G. parasuis HtrA induced a potent antibody response in piglets with Glässer's disease. These observations confirmed that the htrA gene is related to the survival and pathogenicity of G. parasuis.
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Affiliation(s)
- Xuan Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Yan Lin
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiaojuan Xu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Siting Wen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhichao Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Jiayun Gu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Qigai He
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China
| | - Xuwang Cai
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, China.
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16
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Proteolytic Activity of DegP Is Required for the Burkholderia Symbiont To Persist in Its Host Bean Bug. Microbiol Spectr 2023; 11:e0433022. [PMID: 36511662 PMCID: PMC9927360 DOI: 10.1128/spectrum.04330-22] [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] [Indexed: 12/15/2022] Open
Abstract
Symbiosis requires the adaptation of symbiotic bacteria to the host environment. Symbiotic factors for bacterial adaptation have been studied in various experimental models, including the Burkholderia-bean bug symbiosis model. Previously identified symbiotic factors of Burkholderia symbionts of bean bugs provided insight into the host environment being stressful to the symbionts. Because DegP, which functions as both a protease and a chaperone, supports bacterial growth under various stressful conditions, we hypothesized that DegP might be a novel symbiotic factor of Burkholderia symbionts in the symbiotic association with bean bugs. The expression level of degP was highly elevated in symbiotic Burkholderia cells in comparison with cultured cells. When the degP-deficient strain competed for symbiotic association against the wild-type strain, the ΔdegP strain showed no symbiotic competitiveness. In vivo monoinfection with the ΔdegP strain revealed a lower symbiont titer in the symbiotic organ than that of the wild-type strain, indicating that the ΔdegP strain failed to persist in the host. In in vitro assays, the ΔdegP strain showed susceptibility to heat and high-salt stressors and a decreased level of biofilm formation. To further determine the role of the proteolytic activity of DegP in symbiosis, we generated missense mutant DegPS248A exhibiting a defect in protease activity only. The ΔdegP strain complemented with degPS248A showed in vitro characteristics similar to those of the ΔdegP strain and failed to persist in the symbiotic organ. Together, the results of our study demonstrated that the proteolytic activity of DegP, which is involved in the stress resistance and biofilm formation of the Burkholderia symbiont, plays an essential role in symbiotic persistence in the host bean bug. IMPORTANCE Bacterial DegP has dual functions as a protease and a chaperone and supports bacterial growth under stressful conditions. In symbioses involving bacteria, bacterial symbionts encounter various stressors and may need functional DegP for symbiotic association with the host. Using the Burkholderia-bean bug symbiosis model, which is a useful model for identifying bacterial symbiotic factors, we demonstrated that DegP is indeed a symbiotic factor of Burkholderia persistence in its host bean bug. In vitro experiments to understand the symbiotic mechanisms of degP revealed that degP confers resistance to heat and high-salt stresses. In addition, degP supports biofilm formation, which is a previously identified persistence factor of the Burkholderia symbiont. Furthermore, using a missense mutation in a protease catalytic site of degP, we specifically elucidated that the proteolytic activity of degP plays essential roles in stress resistance, biofilm formation, and, thus, symbiotic persistence in the host bean bug.
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17
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Dimitrova YN, Gutierrez JA, Huard K. It's ok to be outnumbered - sub-stoichiometric modulation of homomeric protein complexes. RSC Med Chem 2023; 14:22-46. [PMID: 36760737 PMCID: PMC9890894 DOI: 10.1039/d2md00212d] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 10/21/2022] [Indexed: 11/06/2022] Open
Abstract
An arsenal of molecular tools with increasingly diversified mechanisms of action is being developed by the scientific community to enable biological interrogation and pharmaceutical modulation of targets and pathways of ever increasing complexity. While most small molecules interact with the target of interest in a 1 : 1 relationship, a noteworthy number of recent examples were reported to bind in a sub-stoichiometric manner to a homomeric protein complex. This approach requires molecular understanding of the physiologically relevant protein assemblies and in-depth characterization of the compound's mechanism of action. The recent literature examples summarized here were selected to illustrate methods used to identify and characterize molecules with such mechanisms. The concept of one small molecule targeting a homomeric protein assembly is not new but the subject deserves renewed inspection in light of emerging technologies and increasingly diverse target biology, to ensure relevant in vitro systems are used and valuable compounds with potentially novel sub-stoichiometric mechanisms of action aren't overlooked.
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Affiliation(s)
| | | | - Kim Huard
- Genentech 1 DNA Way South San Francisco CA 94080 USA
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18
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Yang G, Mu X, Pan X, Tang Y, Yao Q, Wang Y, Jiang F, Du F, Xie J, Zhou X, Yuan X. Ligand engineering of Au 44 nanoclusters for NIR-II luminescent and photoacoustic imaging-guided cancer photothermal therapy. Chem Sci 2023; 14:4308-4318. [PMID: 37123188 PMCID: PMC10132122 DOI: 10.1039/d2sc05729h] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 02/14/2023] [Indexed: 04/05/2023] Open
Abstract
A theranostic probe was developed by conjugating NIR-II emitting Au44MBA26 nanoclusters with photothermal Cy7 molecules via click chemistry, achieving NIR-II luminescent and photoacoustic imaging-guided cancer photothermal therapy.
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Affiliation(s)
- Ge Yang
- School of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China
| | - Xueluer Mu
- Key Lab of Biobased Polymer Materials of Shandong Provincial Education Department, School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China
| | - Xinxin Pan
- School of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China
| | - Ying Tang
- Key Lab of Biobased Polymer Materials of Shandong Provincial Education Department, School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China
| | - Qiaofeng Yao
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou, 350207, PR China
| | - Yaru Wang
- School of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China
| | - Fuyi Jiang
- School of Environment and Material Engineering, Yantai University, Yantai, 264005, PR China
| | - Fanglin Du
- School of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China
| | - Jianping Xie
- Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou, 350207, PR China
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore
| | - Xianfeng Zhou
- Key Lab of Biobased Polymer Materials of Shandong Provincial Education Department, School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China
| | - Xun Yuan
- School of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China
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19
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Carrier MC, Lalaouna D, Massé E. Hfq protein and GcvB small RNA tailoring of oppA target mRNA to levels allowing translation activation by MicF small RNA in Escherichia coli. RNA Biol 2023; 20:59-76. [PMID: 36860088 PMCID: PMC9988348 DOI: 10.1080/15476286.2023.2179582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
Traffic of molecules across the bacterial membrane mainly relies on porins and transporters, whose expression must adapt to environmental conditions. To ensure bacterial fitness, synthesis and assembly of functional porins and transporters are regulated through a plethora of mechanisms. Among them, small regulatory RNAs (sRNAs) are known to be powerful post-transcriptional regulators. In Escherichia coli, the MicF sRNA is known to regulate only four targets, a very narrow targetome for a sRNA responding to various stresses, such as membrane stress, osmotic shock, or thermal shock. Using an in vivo pull-down assay combined with high-throughput RNA sequencing, we sought to identify new targets of MicF to better understand its role in the maintenance of cellular homoeostasis. Here, we report the first positively regulated target of MicF, the oppA mRNA. The OppA protein is the periplasmic component of the Opp ATP-binding cassette (ABC) oligopeptide transporter and regulates the import of short peptides, some of them bactericides. Mechanistic studies suggest that oppA translation is activated by MicF through a mechanism of action involving facilitated access to a translation-enhancing region in oppA 5'UTR. Intriguingly, MicF activation of oppA translation depends on cross-regulation by negative trans-acting effectors, the GcvB sRNA and the RNA chaperone protein Hfq.
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Affiliation(s)
- Marie-Claude Carrier
- Department of Biochemistry and Functional Genomics, RNA Group, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - David Lalaouna
- Department of Biochemistry and Functional Genomics, RNA Group, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Eric Massé
- Department of Biochemistry and Functional Genomics, RNA Group, Université de Sherbrooke, Sherbrooke, Québec, Canada
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20
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Estabragh AM, Sadeghi HMM, Akbari V. Co-Expression of Chaperones for Improvement of Soluble Expression and Purification of An Anti-HER2 scFv in Escherichia Coli. Adv Biomed Res 2022; 11:117. [PMID: 36798911 PMCID: PMC9926028 DOI: 10.4103/abr.abr_351_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 02/18/2022] [Accepted: 03/12/2022] [Indexed: 12/28/2022] Open
Abstract
Background Single-chain fragment variable (scFv) is one of the most commonly used antibody fragments. They offer some advantages over full-length antibodies, including better penetration to target tissues. However, their functional production has been a challenge for manufacturers due to the potential misfolding and formation of inclusion bodies. Here we evaluated the soluble expression and purification of molecular chaperone co-expression. Materials and Methods E. coli BL21(DE3) cells were co-transformed with the mixture of plasmids pKJE7 and pET22b-scFv by the electroporation method. First, L-arabinose was added to induce the expression of molecular chaperones, and then IPTG was used as an inducer to start the expression of anti-HER2 scFv. The effect of cultivation temperature and IPTG concentration on soluble expression of the protein with or without chaperones was evaluated. The soluble expressed protein was subjected to native purification using the Ni-NTA affinity column. Results SDS-PAGE analysis confirmed the successful co-expression of anti-HER2-scFv and DnaK/DnaJ/GrpE chaperones. Co-expression with chaperones and low-temperature cultivation synergistically improved the soluble expression of anti-HER2 scFv. Co-expression with chaperone also exhibited an approximately four-fold increase in the final yield of purified soluble protein. Conclusion The combination of co-expression with chaperones and low temperature presented in this work may be useful for the improvement of commercial production of other scFvs in E. coli as functionally bioactive and soluble form.
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Affiliation(s)
- Amir Mirzapour Estabragh
- Department of Pharmaceutical Biotechnology and Isfahan Pharmaceutical Research Center, Faculty of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hamid Mir Mohammad Sadeghi
- Department of Pharmaceutical Biotechnology and Isfahan Pharmaceutical Research Center, Faculty of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Vajihe Akbari
- Department of Pharmaceutical Biotechnology and Isfahan Pharmaceutical Research Center, Faculty of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran,Address for correspondence: Dr. Vajihe Akbari, Department of Pharmaceutical Biotechnology, Isfahan University of Medical Sciences, Isfahan, Iran. E-mail:
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21
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Watkins DW, Williams SL, Collinson I. A bacterial secretosome for regulated envelope biogenesis and quality control? MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36260397 DOI: 10.1099/mic.0.001255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The Gram-negative bacterial envelope is the first line of defence against environmental stress and antibiotics. Therefore, its biogenesis is of considerable fundamental interest, as well as a challenge to address the growing problem of antimicrobial resistance. All bacterial proteins are synthesised in the cytosol, so inner- and outer-membrane proteins, and periplasmic residents have to be transported to their final destinations via specialised protein machinery. The Sec translocon, a ubiquitous integral inner-membrane (IM) complex, is key to this process as the major gateway for protein transit from the cytosol to the cell envelope; this can be achieved during their translation, or afterwards. Proteins need to be directed into the inner-membrane (usually co-translational), otherwise SecA utilises ATP and the proton-motive-force (PMF) to drive proteins across the membrane post-translationally. These proteins are then picked up by chaperones for folding in the periplasm, or delivered to the β-barrel assembly machinery (BAM) for incorporation into the outer-membrane. The core hetero-trimeric SecYEG-complex forms the hub for an extensive network of interactions that regulate protein delivery and quality control. Here, we conduct a biochemical exploration of this 'secretosome' -a very large, versatile and inter-changeable assembly with the Sec-translocon at its core; featuring interactions that facilitate secretion (SecDF), inner- and outer-membrane protein insertion (respectively, YidC and BAM), protein folding and quality control (e.g. PpiD, YfgM and FtsH). We propose the dynamic interplay amongst these, and other factors, act to ensure efficient envelope biogenesis, regulated to accommodate the requirements of cell elongation and division. We believe this organisation is critical for cell wall biogenesis and remodelling and thus its perturbation could be a means for the development of anti-microbials.
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Affiliation(s)
- Daniel W Watkins
- School of Biochemistry, University of Bristol, BS8 1TD, UK.,Present address: CytoSeek, Science Creates Old Market, Midland Road, Bristol, BS20JZ, UK
| | | | - Ian Collinson
- School of Biochemistry, University of Bristol, BS8 1TD, UK
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22
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Park Y, Eyal Z, Pekker P, Chevrier DM, Lefèvre CT, Arnoux P, Armengaud J, Monteil CL, Gal A, Pósfai M, Faivre D. Periplasmic Bacterial Biomineralization of Copper Sulfide Nanoparticles. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2203444. [PMID: 35975419 PMCID: PMC9534983 DOI: 10.1002/advs.202203444] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Indexed: 06/15/2023]
Abstract
Metal sulfides are a common group of extracellular bacterial biominerals. However, only a few cases of intracellular biomineralization are reported in this group, mostly limited to greigite (Fe3 S4 ) in magnetotactic bacteria. Here, a previously unknown periplasmic biomineralization of copper sulfide produced by the magnetotactic bacterium Desulfamplus magnetovallimortis strain BW-1, a species known to mineralize greigite (Fe3 S4 ) and magnetite (Fe3 O4 ) in the cytoplasm is reported. BW-1 produces hundreds of spherical nanoparticles, composed of 1-2 nm substructures of a poorly crystalline hexagonal copper sulfide structure that remains in a thermodynamically unstable state. The particles appear to be surrounded by an organic matrix as found from staining and electron microscopy inspection. Differential proteomics suggests that periplasmic proteins, such as a DegP-like protein and a heavy metal-binding protein, could be involved in this biomineralization process. The unexpected periplasmic formation of copper sulfide nanoparticles in BW-1 reveals previously unknown possibilities for intracellular biomineralization that involves intriguing biological control and holds promise for biological metal recovery in times of copper shortage.
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Affiliation(s)
- Yeseul Park
- Aix‐Marseille UniversityFrench Alternative Energies and Atomic Energy Commission (CEA)French National Center for Scientific Research (CNRS)UMR7265 Institute of Biosciences and Biotechnologies of Aix‐Marseille (BIAM)Saint‐Paul‐lez‐Durance13108France
| | - Zohar Eyal
- Department of Plant and Environmental SciencesWeizmann Institute of ScienceRehovot7610001Israel
| | - Péter Pekker
- Nanolab, Research Institute of Biomolecular and Chemical EngineeringUniversity of PannoniaEgyetem st. 10Veszprém8200Hungary
| | - Daniel M. Chevrier
- Aix‐Marseille UniversityFrench Alternative Energies and Atomic Energy Commission (CEA)French National Center for Scientific Research (CNRS)UMR7265 Institute of Biosciences and Biotechnologies of Aix‐Marseille (BIAM)Saint‐Paul‐lez‐Durance13108France
| | - Christopher T. Lefèvre
- Aix‐Marseille UniversityFrench Alternative Energies and Atomic Energy Commission (CEA)French National Center for Scientific Research (CNRS)UMR7265 Institute of Biosciences and Biotechnologies of Aix‐Marseille (BIAM)Saint‐Paul‐lez‐Durance13108France
| | - Pascal Arnoux
- Aix‐Marseille UniversityFrench Alternative Energies and Atomic Energy Commission (CEA)French National Center for Scientific Research (CNRS)UMR7265 Institute of Biosciences and Biotechnologies of Aix‐Marseille (BIAM)Saint‐Paul‐lez‐Durance13108France
| | - Jean Armengaud
- Medicines and Healthcare Technologies Department (DMTS) University of Paris‐SaclayFrench Alternative Energies and Atomic Energy Commission (CEA)National Research Institute for Agriculture, Food and the Environment (INRAE)Pharmacology and Immunoanalysis unit (SPI)Bagnols‐sur‐Cèze30200France
| | - Caroline L. Monteil
- Aix‐Marseille UniversityFrench Alternative Energies and Atomic Energy Commission (CEA)French National Center for Scientific Research (CNRS)UMR7265 Institute of Biosciences and Biotechnologies of Aix‐Marseille (BIAM)Saint‐Paul‐lez‐Durance13108France
| | - Assaf Gal
- Department of Plant and Environmental SciencesWeizmann Institute of ScienceRehovot7610001Israel
| | - Mihály Pósfai
- Nanolab, Research Institute of Biomolecular and Chemical EngineeringUniversity of PannoniaEgyetem st. 10Veszprém8200Hungary
- ELKH‐PE Environmental Mineralogy Research GroupEgyetem st. 10Veszprém8200Hungary
| | - Damien Faivre
- Aix‐Marseille UniversityFrench Alternative Energies and Atomic Energy Commission (CEA)French National Center for Scientific Research (CNRS)UMR7265 Institute of Biosciences and Biotechnologies of Aix‐Marseille (BIAM)Saint‐Paul‐lez‐Durance13108France
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The Discovery of the Role of Outer Membrane Vesicles against Bacteria. Biomedicines 2022; 10:biomedicines10102399. [PMID: 36289660 PMCID: PMC9598313 DOI: 10.3390/biomedicines10102399] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/02/2022] [Accepted: 09/22/2022] [Indexed: 11/23/2022] Open
Abstract
Gram-negative bacteria are intrinsically resistant to many commercialized antibiotics. The outer membrane (OM) of Gram-negative bacteria prevents the entry of such antibiotics. Outer membrane vesicles (OMV) are naturally released from the OM of Gram-negative bacteria for a range of purposes, including competition with other bacteria. OMV may carry, as part of the membrane or lumen, molecules with antibacterial activity. Such OMV can be exposed to and can fuse with the cell surface of different bacterial species. In this review we consider how OMV can be used as tools to deliver antimicrobial agents. This includes the characteristics of OMV production and how this process can be used to create the desired antibacterial activity of OMV.
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An Unprecedented Tolerance to Deletion of the Periplasmic Chaperones SurA, Skp, and DegP in the Nosocomial Pathogen Acinetobacter baumannii. J Bacteriol 2022; 204:e0005422. [PMID: 36106853 PMCID: PMC9578438 DOI: 10.1128/jb.00054-22] [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] [Indexed: 11/20/2022] Open
Abstract
The outer membrane (OM) of Gram-negative bacteria efficiently protects from harmful environmental stresses such as antibiotics, disinfectants, or dryness. The main constituents of the OM are integral OM β-barrel proteins (OMPs). In Gram-negative bacteria such as Escherichia coli, Yersinia enterocolitica, and Pseudomonas aeruginosa, the insertion of OMPs depends on a sophisticated biogenesis pathway. This comprises the SecYEG translocon, which enables inner membrane (IM) passage; the chaperones SurA, Skp, and DegP, which facilitate the passage of β-barrel OMPs through the periplasm; and the β-barrel assembly machinery (BAM), which facilitates insertion into the OM. In E. coli, Y. enterocolitica, and P. aeruginosa, the deletion of SurA is particularly detrimental and leads to a loss of OM integrity, sensitization to antibiotic treatment, and reduced virulence. In search of targets that could be exploited to develop compounds that interfere with OM integrity in Acinetobacter baumannii, we employed the multidrug-resistant strain AB5075 to generate single gene knockout strains lacking individual periplasmic chaperones. In contrast to E. coli, Y. enterocolitica, and P. aeruginosa, AB5075 tolerates the lack of SurA, Skp, or DegP with only weak mutant phenotypes. While the double knockout strains ΔsurAΔskp and ΔsurAΔdegP are conditionally lethal in E. coli, all double deletions were well tolerated by AB5075. Strikingly, even a triple-knockout strain of AB5075, lacking surA, skp, and degP, was viable. IMPORTANCEAcinetobacter baumannii is a major threat to human health due to its ability to persist in the hospital environment, resistance to antibiotic treatment, and ability to deploy multiple and redundant virulence factors. In a rising number of cases, infections with multidrug-resistant A. baumannii end up fatally, because all antibiotic treatment options fail. Thus, novel targets have to be identified and alternative therapeutics have to be developed. The knockout of periplasmic chaperones has previously proven to significantly reduce virulence and even break antibiotic resistance in other Gram-negative pathogens. Our study in A. baumannii demonstrates how variable the importance of the periplasmic chaperones SurA, Skp, and DegP can be and suggests the existence of mechanisms allowing A. baumannii to cope with the lack of the three periplasmic chaperones.
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Inter-subunit crosstalk via PDZ synergistically governs allosteric activation of proapoptotic HtrA2. Structure 2022; 30:1307-1320.e5. [PMID: 35738282 DOI: 10.1016/j.str.2022.06.001] [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: 11/24/2021] [Revised: 02/28/2022] [Accepted: 05/30/2022] [Indexed: 01/19/2023]
Abstract
The mitochondrial serine protease High-temperature requirement A2 (HtrA2) is associated with various diseases including neurodegenerative disorders and cancer. Despite availability of structural details, the reports on HtrA2's mechanistic regulation that varies with the type of activation signals still remain non-concordant. To expound the role of regulatory PDZ (Postsynaptic density-95/Discs large/Zonula occludens-1) domains in multimodal activation of HtrA2, we generated heterotrimeric HtrA2 variants comprising different numbers of PDZs and/or active-site mutations. Sequential deletion of PDZs from the trimeric ensemble significantly affected its residual activity in a way that proffered a hypothesis advocating inter-molecular allosteric crosstalk via PDZs in HtrA2. Furthermore, structural and computational snapshots affirmed the role of PDZs in secondary structural element formation around the regulatory loops and coordinated reorganization of the N-terminal region. Therefore, apart from providing cues for devising structure-guided therapeutic strategies, this study establishes a physiologically relevant working model of complex allosteric regulation through a trans-mediated cooperatively shared energy landscape.
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26
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Kataoka N, Matsutani M, Matsumoto N, Oda M, Mizumachi Y, Ito K, Tanaka S, Kanesaki Y, Yakushi T, Matsushita K. Mutations in degP and spoT Genes Mediate Response to Fermentation Stress in Thermally Adapted Strains of Acetic Acid Bacterium Komagataeibacter medellinensis NBRC 3288. Front Microbiol 2022; 13:802010. [PMID: 35633714 PMCID: PMC9135448 DOI: 10.3389/fmicb.2022.802010] [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: 10/26/2021] [Accepted: 04/13/2022] [Indexed: 11/30/2022] Open
Abstract
An acetic acid bacterium, Komagataeibacter medellinensis NBRC 3288, was adapted to higher growth temperatures through an experimental evolution approach in acetic acid fermentation conditions, in which the cells grew under high concentrations of ethanol and acetic acid. The thermally adapted strains were shown to exhibit significantly increased growth and fermentation ability, compared to the wild strain, at higher temperatures. Although the wild cells were largely elongated and exhibited a rough cell surface, the adapted strains repressed the elongation and exhibited a smaller cell size and a smoother cell surface than the wild strain. Among the adapted strains, the ITO-1 strain isolated during the initial rounds of adaptation was shown to have three indel mutations in the genes gyrB, degP, and spoT. Among these, two dispensable genes, degP and spoT, were further examined in this study. Rough cell surface morphology related to degP mutation suggested that membrane vesicle-like structures were increased on the cell surface of the wild-type strain but repressed in the ITO-1 strain under high-temperature acetic acid fermentation conditions. The ΔdegP strain could not grow at higher temperatures and accumulated a large amount of membrane vesicles in the culture supernatant when grown even at 30°C, suggesting that the degP mutation is involved in cell surface stability. As the spoT gene of ITO-1 lost a 3′-end of 424 bp, which includes one (Act-4) of the possible two regulatory domains (TGS and Act-4), two spoT mutant strains were created: one (ΔTGSAct) with a drug cassette in between the 5′-half catalytic domain and 3′-half regulatory domains of the gene, and the other (ΔAct-4) in between TGS and Act-4 domains of the regulatory domain. These spoT mutants exhibited different growth responses; ΔTGSAct grew better in both the fermentation and non-fermentation conditions, whereas ΔAct-4 did only under fermentation conditions, such as ITO-1 at higher temperatures. We suggest that cell elongation and/or cell size are largely related to these spoT mutations, which may be involved in fermentation stress and thermotolerance.
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Affiliation(s)
- Naoya Kataoka
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
- Research Center for Thermotolerant Microbial Resources, Yamaguchi University, Yamaguchi, Japan
| | - Minenosuke Matsutani
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
- NODAI Genome Research Center, Tokyo University of Agriculture, Tokyo, Japan
| | - Nami Matsumoto
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
| | - Misuzu Oda
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
| | - Yuki Mizumachi
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
| | - Kohei Ito
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
| | - Shuhei Tanaka
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
| | - Yu Kanesaki
- NODAI Genome Research Center, Tokyo University of Agriculture, Tokyo, Japan
- Research Institute of Green Science and Technology, Shizuoka University, Shizuoka, Japan
| | - Toshiharu Yakushi
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
- Research Center for Thermotolerant Microbial Resources, Yamaguchi University, Yamaguchi, Japan
| | - Kazunobu Matsushita
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
- Research Center for Thermotolerant Microbial Resources, Yamaguchi University, Yamaguchi, Japan
- *Correspondence: Kazunobu Matsushita,
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27
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Perez JG, Carlson ED, Weisser O, Kofman C, Seki K, Des Soye BJ, Karim AS, Jewett MC. Improving genomically recoded Escherichia coli to produce proteins containing non-canonical amino acids. Biotechnol J 2022; 17:e2100330. [PMID: 34894206 DOI: 10.1002/biot.202100330] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 12/12/2022]
Abstract
A genomically recoded Escherichia coli strain that lacks all amber codons and release factor 1 (C321.∆A) enables efficient genetic encoding of chemically diverse non-canonical amino acids (ncAAs) into proteins. While C321.∆A has opened new opportunities in chemical and synthetic biology, this strain has not been optimized for protein production, limiting its utility in widespread industrial and academic applications. To address this limitation, the construction of a series of genomically recoded organisms that are optimized for cellular protein production is described. It is demonstrated that the functional deactivation of nucleases (e.g., rne, endA) and proteases (e.g., lon) increases production of wild-type superfolder green fluorescent protein (sfGFP) and sfGFP containing two ncAAs up to ≈5-fold. Additionally, a genomic IPTG-inducible T7 RNA polymerase (T7RNAP) cassette into these strains is introduced. Using an optimized platform, the ability to introduce two identical N6 -(propargyloxycarbonyl)-L -Lysine residues site specifically into sfGFP with a 17-fold improvement in production relative to the parent strain is demonstrated. The authors envision that their library of organisms will provide the community with multiple options for increased expression of proteins with new and diverse chemistries.
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Affiliation(s)
- Jessica G Perez
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA
| | - Erik D Carlson
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA
| | - Oliver Weisser
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA
| | - Camila Kofman
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA
| | - Kosuke Seki
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA
| | - Benjamin J Des Soye
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA
| | - Ashty S Karim
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA
| | - Michael C Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois, USA
- Simpson Querrey Institute, Northwestern University, Chicago, Illinois, USA
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28
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Abstract
Temperature is one of the ubiquitous signals that control both the development as well as virulence of various microbial species. Therefore their survival is dependent upon initiating appropriate response upon temperature fluctuations. In particular, pathogenic microbes exploit host-temperature sensing mechanisms for triggering the expression of virulence genes. Many studies have revealed that the biomolecules within a cell such as DNA, RNA, lipids and proteins help in sensing change in temperature, thereby acting as thermosensors. This review shall provide an insight into the different mechanisms of thermosensing and how they aid pathogenic microbes in host invasion.
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Caffeine and MDMA (Ecstasy) Exacerbate ER Stress Triggered by Hyperthermia. Int J Mol Sci 2022; 23:ijms23041974. [PMID: 35216090 PMCID: PMC8880705 DOI: 10.3390/ijms23041974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/03/2022] [Accepted: 02/07/2022] [Indexed: 02/04/2023] Open
Abstract
Drugs of abuse can cause local and systemic hyperthermia, a known trigger of endoplasmic reticulum (ER) stress and the unfolded protein response (UPR). Another trigger of ER stress and UPR is ER calcium depletion, which causes ER exodosis, the secretion of ER-resident proteins. In rodent models, club drugs such as 3,4-methylenedioxymethamphetamine (MDMA, ‘ecstasy’) can create hyperthermic conditions in the brain and cause toxicity that is affected by the environmental temperature and the presence of other drugs, such as caffeine. In human studies, MDMA stimulated an acute, dose-dependent increase in core body temperature, but an examination of caffeine and MDMA in combination remains a topic for clinical research. Here we examine the secretion of ER-resident proteins and activation of the UPR under combined exposure to MDMA and caffeine in a cellular model of hyperthermia. We show that hyperthermia triggers the secretion of normally ER-resident proteins, and that this aberrant protein secretion is potentiated by the presence of MDMA, caffeine, or a combination of the two drugs. Hyperthermia activates the UPR but the addition of MDMA or caffeine does not alter the canonical UPR gene expression despite the drug effects on ER exodosis of UPR-related proteins. One exception was increased BiP/GRP78 mRNA levels in MDMA-treated cells exposed to hyperthermia. These findings suggest that club drug use under hyperthermic conditions exacerbates disruption of ER proteostasis, contributing to cellular toxicity.
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30
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Chakraborty A, Bose R, Bose K. Unraveling the Dichotomy of Enigmatic Serine Protease HtrA2. Front Mol Biosci 2022; 9:824846. [PMID: 35187085 PMCID: PMC8850690 DOI: 10.3389/fmolb.2022.824846] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 01/14/2022] [Indexed: 11/19/2022] Open
Abstract
Mitochondrial high-temperature requirement protease A2 (HtrA2) is an integral member of the HtrA family of serine proteases that are evolutionarily conserved from prokaryotes to humans. Involvement in manifold intricate cellular networks and diverse pathophysiological functions make HtrA2 the most enigmatic moonlighting protease amongst the human HtrAs. Despite perpetuating the oligomeric architecture and overall structural fold of its homologs that comprises serine protease and regulatory PDZ domains, subtle conformational alterations and dynamic enzymatic regulation through the distinct allosteric mode of action lead to its functional diversity. This mitochondrial protease upon maturation, exposes its one-of-a-kind N-terminal tetrapeptide (AVPS) motif that binds and subsequently cleaves Inhibitor of Apoptosis Proteins (IAPs) thus promoting cell death, and posing as an important molecule for therapeutic intervention. Interestingly, unlike its other human counterparts, HtrA2 has also been implicated in maintaining the mitochondrial integrity through a bi-functional chaperone-protease activity, the on-off switch of which is yet to be identified. Furthermore, its ability to activate a wide repertoire of substrates through both its N- and C-terminal regions presumably has calibrated its association with several cellular pathways and hence diseases including neurodegenerative disorders and cancer. Therefore, the exclusive structural attributes of HtrA2 that involve multimodal activation, intermolecular PDZ-protease crosstalk, and an allosterically-modulated trimeric active-site ensemble have enabled the protease to evolve across species and partake functions that are fine-tuned for maintaining cellular homeostasis and mitochondrial proteome quality control in humans. These unique features along with its multitasking potential make HtrA2 a promising therapeutic target both in cancer and neurodegeneration.
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Affiliation(s)
- Ayon Chakraborty
- Integrated Biophysics and Structural Biology Lab, ACTREC, Tata Memorial Centre, Navi Mumbai, India
| | - Roshnee Bose
- Integrated Biophysics and Structural Biology Lab, ACTREC, Tata Memorial Centre, Navi Mumbai, India
| | - Kakoli Bose
- Integrated Biophysics and Structural Biology Lab, ACTREC, Tata Memorial Centre, Navi Mumbai, India
- Homi Bhabha National Institute, BARC Training School Complex, Mumbai, India
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31
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APP deficiency and HTRA2 modulates PrPc proteostasis in human cancer cells. BBA ADVANCES 2022; 2:100035. [PMID: 37082595 PMCID: PMC10074928 DOI: 10.1016/j.bbadva.2021.100035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 12/09/2021] [Accepted: 12/14/2021] [Indexed: 11/23/2022] Open
Abstract
Cellular protein homeostasis (proteostasis) requires an accurate balance between protein biosynthesis, folding, and degradation, and its instability is causally related to human diseases and cancers. Here, we created numerous engineered cancer cell lines targeting APP (amyloid ß precursor protein) and/or PRNP (cellular prion) genes and we showed that APP knocking-down impaired PRNP mRNA level and vice versa, suggesting a link between their gene regulation. PRNPKD, APPKD and PRNPKD/APPKD HeLa cells encountered major difficulties to grow in a 3D tissue-like environment. Unexpectedly, we found a cytoplasmic accumulation of the PrPc protein without PRNP gene up regulation, in both APPKD and APPKO HeLa cells. Interestingly, APP and/or PRNP gene ablation enhanced the chaperone/serine protease HTRA2 gene expression, which is a protein processing quality factor involved in Alzheimer's disease. Importantly, HTRA2 gene silencing decreased PRNP mRNA level and lowered PrPc protein amounts, and conversely, HTRA2 overexpression increased PRNP gene regulation and enhanced membrane-anchored and cytoplasmic PrPc fractions. PrPc, APP and HTRA2 destabilized membrane-associated CD24 protein, suggesting changes in the lipid raft structure. Our data show for the first time that APP and the dual chaperone/serine protease HTRA2 protein could modulate PrPc proteostasis hampering cancer cell behavior.
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32
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Karyolaimos A, de Gier JW. Strategies to Enhance Periplasmic Recombinant Protein Production Yields in Escherichia coli. Front Bioeng Biotechnol 2021; 9:797334. [PMID: 34970535 PMCID: PMC8712718 DOI: 10.3389/fbioe.2021.797334] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 11/24/2021] [Indexed: 11/29/2022] Open
Abstract
Main reasons to produce recombinant proteins in the periplasm of E. coli rather than in its cytoplasm are to -i- enable disulfide bond formation, -ii- facilitate protein isolation, -iii- control the nature of the N-terminus of the mature protein, and -iv- minimize exposure to cytoplasmic proteases. However, hampered protein targeting, translocation and folding as well as protein instability can all negatively affect periplasmic protein production yields. Strategies to enhance periplasmic protein production yields have focused on harmonizing secretory recombinant protein production rates with the capacity of the secretory apparatus by transcriptional and translational tuning, signal peptide selection and engineering, increasing the targeting, translocation and periplasmic folding capacity of the production host, preventing proteolysis, and, finally, the natural and engineered adaptation of the production host to periplasmic protein production. Here, we discuss these strategies using notable examples as a thread.
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Affiliation(s)
| | - Jan-Willem de Gier
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
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33
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Wen X, Yang Z, Ding S, Yang H, Zhang L, Lu C, Lu Q. Analysis of the changes of electron transfer and heterogeneity of photosystem II in Deg1-reduced Arabidopsis plants. PHOTOSYNTHESIS RESEARCH 2021; 150:159-177. [PMID: 33993381 DOI: 10.1007/s11120-021-00842-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 05/04/2021] [Indexed: 05/07/2023]
Abstract
Deg1 protease functions in protease and chaperone of PSII complex components, but few works were performed to study the effects of Deg1 on electron transport activities on the donor and acceptor side of PSII and its correlation with the photoprotection of PSII during photoinhibition. Therefore, we performed systematic and comprehensive investigations of electron transfers on the donor and acceptor sides of photosystem II (PSII) in the Deg1-reduced transgenic lines deg1-2 and deg1-4. Both the maximal quantum efficiency of PSII photochemistry (Fv/Fm) and the actual PSII efficiency (ΦPSII) decreased significantly in the transgenic plants. Increases in nonphotochemical quenching (NPQ) and the dissipated energy flux per reaction center (DI0/RC) were also shown in the transgenic plants. Along with the decreased D1, CP47, and CP43 content, these results suggested photoinhibition under growth light conditions in transgenic plants. Decreased Deg1 caused inhibition of electron transfer on the PSII reducing side, leading to a decline in the number of QB-reducing centers and accumulation of QB-nonreducing centers. The Tm of the Q band shifted from 5.7 °C in the wild-type plant to 10.4 °C and 14.2 °C in the deg1-2 and deg1-4 plants, respectively, indicating an increase in the stability of S2QA¯ in transgenic plants. PSIIα in the transgenic plants largely reduced, while PSIIβ and PSIIγ increased with the decline in the Deg1 levels in transgenic plants suggesting PSIIα centers gradually converted into PSIIβ and PSIIγ centers in the transgenic plants. Besides, the connectivity of PSIIα and PSIIβ was downregulated in transgenic plants. Our results reveal that downregulation of Deg1 protein levels induced photoinhibition in transgenic plants, leading to loss of PSII activities on both the donor and acceptor sides in transgenic plants. These results give a new insight into the regulation role of Deg1 in PSII electron transport.
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Affiliation(s)
- Xiaogang Wen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100093, China
| | - Zhipan Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Shunhua Ding
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Huixia Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Lixin Zhang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, 85 Minglun Street, Kaifeng, 475001, China
| | - Congming Lu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018, China.
| | - Qingtao Lu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
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34
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Gollapalli P, Selvan G T, H M, Shetty P, Kumari N S. Genome-scale protein interaction network construction and topology analysis of functional hypothetical proteins in Helicobacter pylori divulges novel therapeutic targets. Microb Pathog 2021; 161:105293. [PMID: 34800634 DOI: 10.1016/j.micpath.2021.105293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/25/2021] [Accepted: 11/12/2021] [Indexed: 02/07/2023]
Abstract
The emergence and spread of multi-drug resistance among Helicobacter pylori (H. pylori) strain raise more stakes for genetic research for discovering new drugs. The quantity of uncharacterized hypothetical proteins in the genome may provide an opportunity to explore their property and promulgation could act as a platform for designing the drugs, making them an intriguing genetic target. In this context, the present study aims to identify the key hypothetical proteins (HPs) and their biological regulatory processes in H. pylori. This investigation could provide a foundation to establish the molecular connectivity among the pathways using topological analysis of the protein interaction networks (PINs). The giant network derived from the extended network has 374 nodes connected via 925 edges. A total of 43 proteins with high betweenness centrality (BC), 54 proteins with a large degree, and 23 proteins with high BC and large degrees have been identified. HP 1479, HP 0056, HP 1481, HP 1021, HP 0043, HP 1019, gmd, flgA, HP 0472, HP 1486, HP 1478, and HP 1473 are categorized as hub nodes because they have a higher number of direct connections and are potentially more important in understanding HP's molecular interactions. The pathway enrichment analysis of the network clusters revealed significant involvement of HPs in pathways such as flagellar assembly, bacterial chemotaxis and lipopolysaccharide biosynthesis. This comprehensive computational study revealed HP's functional role and its druggability characteristics, which could be useful in the development of drugs to combat H. pylori infections.
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Affiliation(s)
- Pavan Gollapalli
- Central Research Laboratory, KS Hegde Medical Academy, Nitte (Deemed to be University), Mangalore, 575018, Karnataka, India.
| | - Tamizh Selvan G
- Central Research Laboratory, KS Hegde Medical Academy, Nitte (Deemed to be University), Mangalore, 575018, Karnataka, India
| | - Manjunatha H
- Department of Biochemistry, Jnana Bharathi Campus, Bangalore University, Bangalore, Karnataka, 560056, India
| | - Praveenkumar Shetty
- Central Research Laboratory, KS Hegde Medical Academy, Nitte (Deemed to be University), Mangalore, 575018, Karnataka, India
| | - Suchetha Kumari N
- Central Research Laboratory, KS Hegde Medical Academy, Nitte (Deemed to be University), Mangalore, 575018, Karnataka, India
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Anil A, Apte S, Joseph J, Parthasarathy A, Madhavan S, Banerjee A. Pyruvate Oxidase as a Key Determinant of Pneumococcal Viability during Transcytosis across Brain Endothelium. J Bacteriol 2021; 203:e0043921. [PMID: 34606370 PMCID: PMC8604078 DOI: 10.1128/jb.00439-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 09/23/2021] [Indexed: 01/23/2023] Open
Abstract
Streptococcus pneumoniae invades a myriad of host tissues following efficient breaching of cellular barriers. However, strategies adopted by pneumococcus for evasion of host intracellular defenses governing successful transcytosis across host cellular barriers remain elusive. In this study, using brain endothelium as a model host barrier, we observed that pneumococcus containing endocytic vacuoles (PCVs), formed following S. pneumoniae internalization into brain microvascular endothelial cells (BMECs), undergo early maturation and acidification, with a major subset acquiring lysosome-like characteristics. Exploration of measures that would preserve pneumococcal viability in the lethal acidic pH of these lysosome-like vacuoles revealed a critical role of the two-component system response regulator, CiaR, which was previously implicated in induction of acid tolerance response. Pyruvate oxidase (SpxB), a key sugar-metabolizing enzyme that catalyzes oxidative decarboxylation of pyruvate to acetyl phosphate, was found to contribute to acid stress tolerance, presumably via acetyl phosphate-mediated phosphorylation and activation of CiaR, independent of its cognate kinase CiaH. Hydrogen peroxide, the by-product of an SpxB-catalyzed reaction, was also found to improve pneumococcal intracellular survival by oxidative inactivation of lysosomal cysteine cathepsins, thus compromising the degradative capacity of the host lysosomes. As expected, a ΔspxB mutant was found to be significantly attenuated in its ability to survive inside the BMEC endocytic vacuoles, reflecting its reduced transcytosis ability. Collectively, our studies establish SpxB as an important virulence determinant facilitating pneumococcal survival inside host cells, ensuring successful trafficking across host cellular barriers. IMPORTANCE Host cellular barriers have innate immune defenses to restrict microbial passage into sterile compartments. Here, by focusing on the blood-brain barrier endothelium, we investigated mechanisms that enable Streptococcus pneumoniae to traverse through host barriers. Pyruvate oxidase, a pneumococcal sugar-metabolizing enzyme, was found to play a crucial role in this via generation of acetyl phosphate and hydrogen peroxide. A two-pronged approach consisting of acetyl phosphate-mediated activation of acid tolerance response and hydrogen peroxide-mediated inactivation of lysosomal enzymes enabled pneumococci to maintain viability inside the degradative vacuoles of the brain endothelium for successful transcytosis across the barrier. Thus, pyruvate oxidase is a key virulence determinant and can potentially serve as a viable candidate for therapeutic interventions for better management of invasive pneumococcal diseases.
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Affiliation(s)
- Anjali Anil
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Shruti Apte
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Jincy Joseph
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Akhila Parthasarathy
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Shilpa Madhavan
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
| | - Anirban Banerjee
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, Maharashtra, India
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Ali MQ, Kohler TP, Schulig L, Burchhardt G, Hammerschmidt S. Pneumococcal Extracellular Serine Proteases: Molecular Analysis and Impact on Colonization and Disease. Front Cell Infect Microbiol 2021; 11:763152. [PMID: 34790590 PMCID: PMC8592123 DOI: 10.3389/fcimb.2021.763152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 10/08/2021] [Indexed: 11/24/2022] Open
Abstract
The pathobiont Streptococcus pneumoniae causes life-threatening diseases, including pneumonia, sepsis, meningitis, or non-invasive infections such as otitis media. Serine proteases are enzymes that have been emerged during evolution as one of the most abundant and functionally diverse group of proteins in eukaryotic and prokaryotic organisms. S. pneumoniae expresses up to four extracellular serine proteases belonging to the category of trypsin-like or subtilisin-like family proteins: HtrA, SFP, PrtA, and CbpG. These serine proteases have recently received increasing attention because of their immunogenicity and pivotal role in the interaction with host proteins. This review is summarizing and focusing on the molecular and functional analysis of pneumococcal serine proteases, thereby discussing their contribution to pathogenesis.
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Affiliation(s)
- Murtadha Q Ali
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute of Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Thomas P Kohler
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute of Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Lukas Schulig
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, University of Greifswald, Greifswald, Germany
| | - Gerhard Burchhardt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute of Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute of Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
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37
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Sučec I, Bersch B, Schanda P. How do Chaperones Bind (Partly) Unfolded Client Proteins? Front Mol Biosci 2021; 8:762005. [PMID: 34760928 PMCID: PMC8573040 DOI: 10.3389/fmolb.2021.762005] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 10/06/2021] [Indexed: 01/03/2023] Open
Abstract
Molecular chaperones are central to cellular protein homeostasis. Dynamic disorder is a key feature of the complexes of molecular chaperones and their client proteins, and it facilitates the client release towards a folded state or the handover to downstream components. The dynamic nature also implies that a given chaperone can interact with many different client proteins, based on physico-chemical sequence properties rather than on structural complementarity of their (folded) 3D structure. Yet, the balance between this promiscuity and some degree of client specificity is poorly understood. Here, we review recent atomic-level descriptions of chaperones with client proteins, including chaperones in complex with intrinsically disordered proteins, with membrane-protein precursors, or partially folded client proteins. We focus hereby on chaperone-client interactions that are independent of ATP. The picture emerging from these studies highlights the importance of dynamics in these complexes, whereby several interaction types, not only hydrophobic ones, contribute to the complex formation. We discuss these features of chaperone-client complexes and possible factors that may contribute to this balance of promiscuity and specificity.
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Affiliation(s)
- Iva Sučec
- CEA, CNRS, Institut de Biologie Structurale (IBS), Univ. Grenoble Alpes, Grenoble, France
| | - Beate Bersch
- CEA, CNRS, Institut de Biologie Structurale (IBS), Univ. Grenoble Alpes, Grenoble, France
| | - Paul Schanda
- CEA, CNRS, Institut de Biologie Structurale (IBS), Univ. Grenoble Alpes, Grenoble, France.,Institute of Science and Technology Austria, Klosterneuburg, Austria
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38
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OmpF Downregulation Mediated by Sigma E or OmpR Activation Confers Cefalexin Resistance in Escherichia coli in the Absence of Acquired β-Lactamases. Antimicrob Agents Chemother 2021; 65:e0100421. [PMID: 34460299 DOI: 10.1128/aac.01004-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cefalexin is a widely used first-generation cephalosporin, and resistance in Escherichia coli is caused by extended-spectrum (e.g., CTX-M) and AmpC β-lactamase production and therefore frequently coincides with third-generation cephalosporin resistance. However, we have recently identified large numbers of E. coli isolates from human infections, and from cattle, where cefalexin resistance is not β-lactamase mediated. Here, we show, by studying laboratory-selected mutants, clinical isolates, and isolates from cattle, that OmpF porin disruption or downregulation is a major cause of cefalexin resistance in E. coli. Importantly, we identify multiple regulatory mutations that cause OmpF downregulation. In addition to mutation of ompR, already known to downregulate OmpF and OmpC porin production, we find that rseA mutation, which strongly activates the sigma E regulon, greatly increases DegP production, which degrades OmpF, OmpC, and OmpA. Furthermore, we reveal that mutations affecting lipopolysaccharide structure, exemplified by the loss of GmhB, essential for lipopolysaccharide heptosylation, also modestly activate DegP production, resulting in OmpF degradation. Remarkably, given the critical importance attached to such systems for normal E. coli physiology, we find evidence for DegP-mediated OmpF downregulation and gmhB and rseA loss-of-function mutation in E. coli isolates derived from human infections. Finally, we show that these regulatory mutations enhance the ability of group 1 CTX-M β-lactamase to confer reduced carbapenem susceptibility, particularly those mutations that cause OmpC in addition to OmpF downregulation.
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Overview of Human HtrA Family Proteases and Their Distinctive Physiological Roles and Unique Involvement in Diseases, Especially Cancer and Pregnancy Complications. Int J Mol Sci 2021; 22:ijms221910756. [PMID: 34639128 PMCID: PMC8509474 DOI: 10.3390/ijms221910756] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/27/2021] [Accepted: 10/02/2021] [Indexed: 12/25/2022] Open
Abstract
The mammalian high temperature requirement A (HtrA) proteins are a family of evolutionarily conserved serine proteases, consisting of four homologs (HtrA1-4) that are involved in many cellular processes such as growth, unfolded protein stress response and programmed cell death. In humans, while HtrA1, 2 and 3 are widely expressed in multiple tissues with variable levels, HtrA4 expression is largely restricted to the placenta with the protein released into maternal circulation during pregnancy. This limited expression sets HtrA4 apart from the rest of the family. All four HtrAs are active proteases, and their specific cellular and physiological roles depend on tissue type. The dysregulation of HtrAs has been implicated in many human diseases such as cancer, arthritis, neurogenerative ailments and reproductive disorders. This review first discusses HtrAs broadly and then focuses on the current knowledge of key molecular characteristics of individual human HtrAs, their similarities and differences and their reported physiological functions. HtrAs in other species are also briefly mentioned in the context of understanding the human HtrAs. It then reviews the distinctive involvement of each HtrA in various human diseases, especially cancer and pregnancy complications. It is noteworthy that HtrA4 expression has not yet been reported in any primary tumour samples, suggesting an unlikely involvement of this HtrA in cancer. Collectively, we accentuate that a better understanding of tissue-specific regulation and distinctive physiological and pathological roles of each HtrA will improve our knowledge of many processes that are critical for human health.
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40
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Harkness RW, Toyama Y, Ripstein ZA, Zhao H, Sever AIM, Luan Q, Brady JP, Clark PL, Schuck P, Kay LE. Competing stress-dependent oligomerization pathways regulate self-assembly of the periplasmic protease-chaperone DegP. Proc Natl Acad Sci U S A 2021. [PMID: 34362850 DOI: proc/self/fd/32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
DegP is an oligomeric protein with dual protease and chaperone activity that regulates protein homeostasis and virulence factor trafficking in the periplasm of gram-negative bacteria. A number of oligomeric architectures adopted by DegP are thought to facilitate its function. For example, DegP can form a "resting" hexamer when not engaged to substrates, mitigating undesired proteolysis of cellular proteins. When bound to substrate proteins or lipid membranes, DegP has been shown to populate a variety of cage- or bowl-like oligomeric states that have increased proteolytic activity. Though a number of DegP's substrate-engaged structures have been robustly characterized, detailed mechanistic information underpinning its remarkable oligomeric plasticity and the corresponding interplay between these dynamics and biological function has remained elusive. Here, we have used a combination of hydrodynamics and NMR spectroscopy methodologies in combination with cryogenic electron microscopy to shed light on the apo-DegP self-assembly mechanism. We find that, in the absence of bound substrates, DegP populates an ensemble of oligomeric states, mediated by self-assembly of trimers, that are distinct from those observed in the presence of substrate. The oligomeric distribution is sensitive to solution ionic strength and temperature and is shifted toward larger oligomeric assemblies under physiological conditions. Substrate proteins may guide DegP toward canonical cage-like structures by binding to these preorganized oligomers, leading to changes in conformation. The properties of DegP self-assembly identified here suggest that apo-DegP can rapidly shift its oligomeric distribution in order to respond to a variety of biological insults.
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Affiliation(s)
- Robert W Harkness
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; .,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada.,Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Yuki Toyama
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada.,Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Zev A Ripstein
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada.,Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Huaying Zhao
- National Institute of Biomedical Imaging and Bioengineering, NIH, Bethesda, MD 20892
| | - Alexander I M Sever
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada.,Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Qing Luan
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, IN 46556
| | - Jacob P Brady
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada.,Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Patricia L Clark
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, IN 46556
| | - Peter Schuck
- National Institute of Biomedical Imaging and Bioengineering, NIH, Bethesda, MD 20892
| | - Lewis E Kay
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; .,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada.,Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
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41
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Peters K, Schweizer I, Hakenbeck R, Denapaite D. New Insights into Beta-Lactam Resistance of Streptococcus pneumoniae: Serine Protease HtrA Degrades Altered Penicillin-Binding Protein 2x. Microorganisms 2021; 9:microorganisms9081685. [PMID: 34442764 PMCID: PMC8400419 DOI: 10.3390/microorganisms9081685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 08/02/2021] [Accepted: 08/04/2021] [Indexed: 11/18/2022] Open
Abstract
Reduced amounts of the essential penicillin-binding protein 2x (PBP2x) were detected in two cefotaxime-resistant Streptococcus pneumoniae laboratory mutants C405 and C606. These mutants contain two or four mutations in the penicillin-binding domain of PBP2x, respectively. The transcription of the pbp2x gene was not affected in both mutants; thus, the reduced PBP2x amounts were likely due to post-transcriptional regulation. The mutants carry a mutation in the histidine protein kinase gene ciaH, resulting in enhanced gene expression mediated by the cognate response regulator CiaR. Deletion of htrA, encoding a serine protease regulated by CiaR, or inactivation of HtrA proteolytic activity showed that HtrA is indeed responsible for PBP2x degradation in both mutants, and that this affects β-lactam resistance. Depletion of the PBP2xC405 in different genetic backgrounds confirmed that HtrA degrades PBP2xC405. A GFP-PBP2xC405 fusion protein still localized at the septum in the absence of HtrA. The complementation studies in HtrA deletion strains showed that HtrA can be overexpressed in pneumococcal cells to specific levels, depending on the genetic background. Quantitative Western blotting revealed that the PBP2x amount in C405 strain was less than 20% compared to parental strain, suggesting that PBP2x is an abundant protein in S. pneumoniae R6 strain.
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42
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Competing stress-dependent oligomerization pathways regulate self-assembly of the periplasmic protease-chaperone DegP. Proc Natl Acad Sci U S A 2021; 118:2109732118. [PMID: 34362850 DOI: 10.1073/pnas.2109732118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
DegP is an oligomeric protein with dual protease and chaperone activity that regulates protein homeostasis and virulence factor trafficking in the periplasm of gram-negative bacteria. A number of oligomeric architectures adopted by DegP are thought to facilitate its function. For example, DegP can form a "resting" hexamer when not engaged to substrates, mitigating undesired proteolysis of cellular proteins. When bound to substrate proteins or lipid membranes, DegP has been shown to populate a variety of cage- or bowl-like oligomeric states that have increased proteolytic activity. Though a number of DegP's substrate-engaged structures have been robustly characterized, detailed mechanistic information underpinning its remarkable oligomeric plasticity and the corresponding interplay between these dynamics and biological function has remained elusive. Here, we have used a combination of hydrodynamics and NMR spectroscopy methodologies in combination with cryogenic electron microscopy to shed light on the apo-DegP self-assembly mechanism. We find that, in the absence of bound substrates, DegP populates an ensemble of oligomeric states, mediated by self-assembly of trimers, that are distinct from those observed in the presence of substrate. The oligomeric distribution is sensitive to solution ionic strength and temperature and is shifted toward larger oligomeric assemblies under physiological conditions. Substrate proteins may guide DegP toward canonical cage-like structures by binding to these preorganized oligomers, leading to changes in conformation. The properties of DegP self-assembly identified here suggest that apo-DegP can rapidly shift its oligomeric distribution in order to respond to a variety of biological insults.
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43
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Jain M, Yadav P, Joshi B, Joshi A, Kodgire P. Recombinant organophosphorus hydrolase (OPH) expression in E. coli for the effective detection of organophosphate pesticides. Protein Expr Purif 2021; 186:105929. [PMID: 34139322 DOI: 10.1016/j.pep.2021.105929] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 05/18/2021] [Accepted: 06/07/2021] [Indexed: 12/17/2022]
Abstract
Accumulation and exposure of organophosphate pesticides are of great concern today owing to their abundant usage and potential health hazards. Harmful effects of organophosphate pesticide exposure and limitations of the available treatment methods necessitate the development of reliable, selective, cost-effective, and sensitive methods of detection. We developed a novel biosensor based on the enzymatic action of recombinant organophosphorus hydrolase (OPH) expressed in E. coli. We report the development of colorimetric biosensors made of His-Nus-OPH as well as His-Nus-OPH loaded alginate microspheres. The colorimetric detection method developed using solution-phase and alginate-encapsulated His-Nus-OPH exhibited detection limits of 0.045 and 0.039 mM, respectively, for ethyl paraoxon, and 0.101 and 0.049 mM, respectively, for methyl parathion. Additionally, fluorescence measurement using pH-sensitive fluorescein isothiocyanate (FITC) was used to sense the quantity of organophosphorus pesticides. The fluorometric detection method using solution-phase His-Nus-OPH, with ethyl paraoxon and methyl parathion as the substrate, reveals the lower limit of detection as 0.014 mM and 0.044 mM, respectively. Our results demonstrate the viability of His-Nus-OPH for OP detection with good sensitivity, LOD, and linear range. We report the first use of N-terminal His-NusA-tagged OPH, which enhances solubility significantly and presents a significant advance for the scientific community.
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Affiliation(s)
- Monika Jain
- Discipline of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India
| | - Priyanka Yadav
- Discipline of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India
| | - Bhavana Joshi
- Discipline of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India
| | - Abhijeet Joshi
- Discipline of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India.
| | - Prashant Kodgire
- Discipline of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore, 453552, India.
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Kim H, Wu K, Lee C. Stress-Responsive Periplasmic Chaperones in Bacteria. Front Mol Biosci 2021; 8:678697. [PMID: 34046432 PMCID: PMC8144458 DOI: 10.3389/fmolb.2021.678697] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 04/19/2021] [Indexed: 01/14/2023] Open
Abstract
Periplasmic proteins are involved in a wide range of bacterial functions, including motility, biofilm formation, sensing environmental cues, and small-molecule transport. In addition, a wide range of outer membrane proteins and proteins that are secreted into the media must travel through the periplasm to reach their final destinations. Since the porous outer membrane allows for the free diffusion of small molecules, periplasmic proteins and those that travel through this compartment are more vulnerable to external environmental changes, including those that result in protein unfolding, than cytoplasmic proteins are. To enable bacterial survival under various stress conditions, a robust protein quality control system is required in the periplasm. In this review, we focus on several periplasmic chaperones that are stress responsive, including Spy, which responds to envelope-stress, DegP, which responds to temperature to modulate chaperone/protease activity, HdeA and HdeB, which respond to acid stress, and UgpB, which functions as a bile-responsive chaperone.
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Affiliation(s)
- Hyunhee Kim
- Department of Biological Sciences, Ajou University, Suwon, South Korea
- Molecular, Cellular, and Developmental Biology, Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI, United States
| | - Kevin Wu
- Molecular, Cellular, and Developmental Biology, Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI, United States
- Department of Biophysics, University of Michigan, Ann Arbor, MI, United States
| | - Changhan Lee
- Department of Biological Sciences, Ajou University, Suwon, South Korea
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45
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HtrA serine proteases in cancers: A target of interest for cancer therapy. Biomed Pharmacother 2021; 139:111603. [PMID: 34243596 DOI: 10.1016/j.biopha.2021.111603] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 04/05/2021] [Accepted: 04/12/2021] [Indexed: 11/20/2022] Open
Abstract
The HtrA protein family is composed by evolutionally-conserved serine proteases, which are homologous to the HtrA protein of the model bacterium Escherichia coli. They are widely distributed in organisms including humans, prokaryotes and eukaryotes. Moreover, HtrA family proteins are important regulators of a variety of human physiological processes, which contains the maintenance of mitochondrial homeostasis, cellular signal transduction and apoptosis regulation. The HtrA family has been found to be associated with cancer and could be used as a target for future cancer treatments. The purpose of this article is to review the relationship between these HtrA and cancer and to summarize the latest researches on HtrA and cancer.
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46
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Computational Design of Novel Allosteric Inhibitors for Plasmodium falciparum DegP. Molecules 2021; 26:molecules26092742. [PMID: 34066964 PMCID: PMC8141111 DOI: 10.3390/molecules26092742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/24/2021] [Accepted: 03/31/2021] [Indexed: 11/23/2022] Open
Abstract
The serine protease, DegP exhibits proteolytic and chaperone activities, essential for cellular protein quality control and normal cell development in eukaryotes. The P. falciparum DegP is essential for the parasite survival and required to combat the oscillating thermal stress conditions during the infection, protein quality checks and protein homeostasis in the extra-cytoplasmic compartments, thereby establishing it as a potential target for drug development against malaria. Previous studies have shown that diisopropyl fluorophosphate (DFP) and the peptide SPMFKGV inhibit E. coli DegP protease activity. To identify novel potential inhibitors specific to PfDegP allosteric and the catalytic binding sites, we performed a high throughput in silico screening using Malaria Box, Pathogen Box, Maybridge library, ChEMBL library and the library of FDA approved compounds. The screening helped identify five best binders that showed high affinity to PfDegP allosteric (T0873, T2823, T2801, RJC02337, CD00811) and the catalytic binding site (T0078L, T1524, T2328, BTB11534 and 552691). Further, molecular dynamics simulation analysis revealed RJC02337, BTB11534 as the best hits forming a stable complex. WaterMap and electrostatic complementarity were used to evaluate the novel bio-isosteric chemotypes of RJC02337, that led to the identification of 231 chemotypes that exhibited better binding affinity. Further analysis of the top 5 chemotypes, based on better binding affinity, revealed that the addition of electron donors like nitrogen and sulphur to the side chains of butanoate group are more favoured than the backbone of butanoate group. In a nutshell, the present study helps identify novel, potent and Plasmodium specific inhibitors, using high throughput in silico screening and bio-isosteric replacement, which may be experimentally validated.
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47
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Fantone S, Giannubilo SR, Marzioni D, Tossetta G. HTRA family proteins in pregnancy outcome. Tissue Cell 2021; 72:101549. [PMID: 33915357 DOI: 10.1016/j.tice.2021.101549] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/02/2021] [Accepted: 04/17/2021] [Indexed: 11/29/2022]
Abstract
HTRA (High temperature requirement protease A) family proteins includes HTRA1 (L56 or PRSS11), HTRA2/Omi, HTRA3 (PRSP) and HTRA4. These are oligomeric serine proteases highly conserved from bacteria to humans and are involved in a variety of biological functions including the maintenance of normal cell physiology and pathogenicity such as cell growth, apoptosis, neurodegenerative disorders, inflammation diseases and cancer. These proteins are normally expressed in placental villi during all pregnancy but their expression is found to be altered in pathological pregnancies suggesting a possible role of those proteins in the development of human placenta. Moreover, some HTRA family proteins have also been found in maternal blood and were impaired in pathological pregnancy suggesting a possible role of some of these proteins as early markers of pregnancy outcome. The aim of this review is to summarize the data currently available on the role of HTRA family proteins in pregnancy focalizing their role in pregnancy complications such as Preeclampsia (PE), IntraUterine Growth Restriction (IUGR) and Spontaneus PreTerm Birth (SPTB).
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Affiliation(s)
- Sonia Fantone
- Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, 60126, Ancona, Italy
| | - Stefano R Giannubilo
- Clinic of Obstetrics and Gynaecology, Department of Clinical Sciences, Università Politecnica delle Marche, Salesi Hospital, Azienda Ospedaliero Universitaria, Ancona, Italy
| | - Daniela Marzioni
- Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, 60126, Ancona, Italy
| | - Giovanni Tossetta
- Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, 60126, Ancona, Italy; Clinic of Obstetrics and Gynaecology, Department of Clinical Sciences, Università Politecnica delle Marche, Salesi Hospital, Azienda Ospedaliero Universitaria, Ancona, Italy.
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48
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HtrA family proteases of bacterial pathogens: pros and cons for their therapeutic use. Clin Microbiol Infect 2021; 27:559-564. [DOI: 10.1016/j.cmi.2020.12.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 09/25/2020] [Accepted: 12/16/2020] [Indexed: 12/11/2022]
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49
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Bisht K, Moore JL, Caprioli RM, Skaar EP, Wakeman CA. Impact of temperature-dependent phage expression on Pseudomonas aeruginosa biofilm formation. NPJ Biofilms Microbiomes 2021; 7:22. [PMID: 33727555 PMCID: PMC7966754 DOI: 10.1038/s41522-021-00194-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 02/05/2021] [Indexed: 01/31/2023] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous opportunistic pathogen that forms robust biofilms in the different niches it occupies. Numerous physiological adaptations are required as this organism shifts from soil or aquatic environments to a host-associated lifestyle. While many conditions differ between these niches, temperature shifts are a factor that can contribute to physiological stress during this transition. To understand how temperature impacts biofilm formation in this pathogen, we used proteomic and transcriptomic tools to elucidate physiological responses in environment-relevant vs. host-relevant temperatures. These studies uncovered differential expression of various proteins including a phage protein that is associated with the EPS matrix in P. aeruginosa. This filamentous phage was induced at host temperatures and was required for full biofilm-forming capacity specifically at human body temperature. These data highlight the importance of temperature shift in biofilm formation and suggest bacteriophage proteins could be a possible therapeutic target in biofilm-associated infections.
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Affiliation(s)
- Karishma Bisht
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA
| | - Jessica L Moore
- Department of Chemistry, Vanderbilt University, Nashville, TN, USA
| | | | - Eric P Skaar
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
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50
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Abstract
Bacterial proteases and peptidases are integral to cell physiology and stability, and their necessity in Streptococcus pneumoniae is no exception. Protein cleavage and processing mechanisms within the bacterial cell serve to ensure that the cell lives and functions in its commensal habitat and can respond to new environments presenting stressful conditions. For S. pneumoniae, the human nasopharynx is its natural habitat. In the context of virulence, movement of S. pneumoniae to the lungs, blood, or other sites can instigate responses by the bacteria that result in their proteases serving dual roles of self-protein processors and virulence factors of host protein targets.
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Affiliation(s)
- Mary E Marquart
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, Mississippi USA
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