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Shuvo MN, Halder SK, Alam N, Himel MK, Shil A. Developing phytocompound-based new drugs against multi-drug-resistant Staphylococcus aureus. ROYAL SOCIETY OPEN SCIENCE 2024; 11:231475. [PMID: 39050719 PMCID: PMC11265916 DOI: 10.1098/rsos.231475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 05/28/2024] [Accepted: 06/13/2024] [Indexed: 07/27/2024]
Abstract
Staphylococcus aureus, a prevalent component of the human microbiota, is associated with skin infections to life-threatening diseases, presenting challenges in treatment options and necessitating the development of effective treatments. This study integrated computational and in vitro approaches to identify promising phytocompounds with therapeutic potential. Staphopain B emerged as a target protein for its role in immune evasion, exhibiting stability during molecular dynamic simulation (MDS) with a root mean square deviation value of 2.376 Å. Screening 115 phytocompounds with antibacterial properties from the PubChem database identified 12 with drug-like properties, nine of which showed superior binding affinity to Staphopain B compared to a commercial antibiotic, doxycycline (-7.8 kcal mol-1). Notably, epoxyazadiradione and nimbolide displayed higher estimated free energy of binding scores (-7.91 and -7.93 kcal mol-1, respectively), indicating strong protein-ligand interactions. The root mean square fluctuation values for epoxyazadiradione and nimbolide were 1.097 and 1.034 Å, respectively, which was confirmed through MDS. Crude ethanolic extracts (100% and 70%) of neem (Azadirachta indica) leaves demonstrated narrow inhibition against the bacteria in comparison to doxycycline in the disc-diffusion assay. This study underscores the potential of phytocompounds as therapeutic agents against S. aureus; however, further in vitro experiments and testing of the phytocompounds in vivo are required.
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Affiliation(s)
| | | | - Nuhu Alam
- Department of Botany, Jahangirnagar University, Savar, Dhaka1342, Bangladesh
| | - Mahbubul Kabir Himel
- Department of Botany, Jahangirnagar University, Savar, Dhaka1342, Bangladesh
- Padma Bioresearch, Dhaka1342, Bangladesh
| | - Aparna Shil
- Department of Botany, Jahangirnagar University, Savar, Dhaka1342, Bangladesh
- Padma Bioresearch, Dhaka1342, Bangladesh
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2
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Dehbashi S, Tahmasebi H, Alikhani MY, Shahbazi MA, Arabestani MR. Staphopain mediated virulence and antibiotic resistance alteration in co-infection of Staphylococcus aureus and Pseudomonas aeruginosa: an animal model. BMC Biotechnol 2024; 24:10. [PMID: 38439037 PMCID: PMC10913572 DOI: 10.1186/s12896-024-00840-x] [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: 08/19/2023] [Accepted: 02/22/2024] [Indexed: 03/06/2024] Open
Abstract
Polymicrobial communities lead to worsen the wound infections, due to mixed biofilms, increased antibiotic resistance, and altered virulence production. Promising approaches, including enzymes, may overcome the complicated condition of polymicrobial infections. Therefore, this study aimed to investigate Staphopain A-mediated virulence and resistance alteration in an animal model of Staphylococcus aureus and Pseudomonas aeruginosa co-infection. S. aureus and P. aeruginosa were co-cultured on the L-929 cell line and wound infection in an animal model. Then, recombinant staphopain A was purified and used to treat mono- and co-infections. Following the treatment, changes in virulence factors and resistance were investigated through phenotypic methods and RT-PCR. Staphopain A resulted in a notable reduction in the viability of S. aureus and P. aeruginosa. The biofilm formed in the wound infection in both animal model and cell culture was disrupted remarkably. Moreover, the biofilm-encoding genes, quorum sensing regulating genes, and virulence factors (hemolysin and pyocyanin) controlled by QS were down-regulated in both microorganisms. Furthermore, the resistance to vancomycin and doripenem decreased following treatment with staphopain A. According to this study, staphopain A might promote wound healing and cure co-infection. It seems to be a promising agent to combine with antibiotics to overcome hard-to-cure infections.
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Affiliation(s)
- Sanaz Dehbashi
- Department of Laboratory Sciences, Varastegan Institute of Medical Sciences, Mashhad, Iran
| | - Hamed Tahmasebi
- School of Medicine, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Mohammad Yousef Alikhani
- Department of Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mohammad-Ali Shahbazi
- Department of Biomedical Engineering, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, 9713, Groningen, AV, The Netherlands
| | - Mohammad Reza Arabestani
- Department of Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
- Infectious disease Research center, Hamadan University of Medical Sciences, Hamadan, Iran.
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3
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Li Y, Wang Y, Li C, Zhao D, Hu Q, Zhou M, Du M, Li J, Wan P. The Role of Elastase in Corneal Epithelial Barrier Dysfunction Caused by Pseudomonas aeruginosa Exoproteins. Invest Ophthalmol Vis Sci 2021; 62:7. [PMID: 34232259 PMCID: PMC8316690 DOI: 10.1167/iovs.62.9.7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Purpose To investigate the role of elastase in corneal epithelial barrier dysfunction caused by the exoproteins secreted by Pseudomonas aeruginosa. Methods Exoproteins obtained from Pseudomonas aeruginosa culture supernatant were analyzed by shotgun proteomics approach. In vitro multilayered rabbit corneal epithelial barrier model prepared by air-liquid interface technique (CECs-ALI) were treated with 2 µg/ml exoproteins and/or 8 mM elastase inhibitor. Then the epithelial barrier function was evaluated by transepithelial electrical resistance (TEER) assay and tight junction proteins immunofluorescence. Cell viability and the apoptosis rate were examined by CCK8 assay and flow cytometry. TNF-α, IL-6, IL-8, and IL-1β levels were measured by ELISA. Mice cornea treated with exoproteins and/or elastase inhibitor were evaluated in vivo and in vitro. Results Elastase (24.2%) is one of the major components of exoproteins. After 2 µg/ml exoproteins were applied to CECs-ALI for two hours, TEER decreased from 323.2 ± 2.7 to 104 ± 6.8 Ω/cm2 (P < 0.001). The immunofluorescence results showed a distinct separation in tight junction and significant degradation of ZO-1 and occludin (P < 0.05). Elastase inhibitor (8 mM) alleviated the decrease in TEER value (234 ± 6.8 Ω cm2) induced by exoproteins. Inhibition of elastase decreased the apoptosis rate of CECs treated with exoproteins from 30.2 ± 3.8% to 7.26 ± 1.3% and the levels of inflammatory factors (P < 0.05). Mice corneal epithelium defect could be induced by exoproteins and protected by elastase inhibitor. Conclusions Elastase plays a critical role in corneal epithelial barrier dysfunction caused by Pseudomonas aeruginosa exoproteins via damaging tight junctions. The inhibition of elastase could protect the corneal epithelial barrier via reducing virulence and inflammation.
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Affiliation(s)
- Ye Li
- Department of Ophthalmology, The First Affiliated Hospital, Sun-Yat-sen University, Guangzhou, China
| | - YingWei Wang
- Department of Ophthalmology, The First Affiliated Hospital, Sun-Yat-sen University, Guangzhou, China
| | - ChunWei Li
- Department of Otolaryngology, The First Affiliated Hospital, Sun-Yat-sen University, Guangzhou, China
| | - DePeng Zhao
- School of Pharmaceutical Sciences, Sun-Yat-sen University, Guangzhou, China
| | - QinYuan Hu
- Department of Ophthalmology, The First Affiliated Hospital, Sun-Yat-sen University, Guangzhou, China
| | - Min Zhou
- Department of Ophthalmology, The First Affiliated Hospital, Sun-Yat-sen University, Guangzhou, China
| | - Miao Du
- Department of Ophthalmology, The First Affiliated Hospital, Sun-Yat-sen University, Guangzhou, China
| | - Jian Li
- Department of Otolaryngology, The First Affiliated Hospital, Sun-Yat-sen University, Guangzhou, China
| | - PengXia Wan
- Department of Ophthalmology, The First Affiliated Hospital, Sun-Yat-sen University, Guangzhou, China
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4
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Frey AM, Chaput D, Shaw LN. Insight into the human pathodegradome of the V8 protease from Staphylococcus aureus. Cell Rep 2021; 35:108930. [PMID: 33826899 PMCID: PMC8054439 DOI: 10.1016/j.celrep.2021.108930] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 12/03/2020] [Accepted: 03/11/2021] [Indexed: 12/03/2022] Open
Abstract
Staphylococcus aureus possesses ten extracellular proteases with mostly unknown targets in the human proteome. To assist with bacterial protease target discovery, we have applied and compared two N-terminomics methods to investigate cleavage of human serum proteins by S. aureus V8 protease, discovering 85 host-protein targets. Among these are virulence-relevant complement, iron sequestration, clotting cascade, and host protease inhibitor proteins. Protein cleavage sites have been identified, providing insight into the disruption of host protein function by V8. Complement proteins are cleaved within peptidase and sushi domains, and host protease inhibitors are cleaved outside their protease-trapping motifs. Our data highlight the potential for further application of N-terminomics in discovery of bacterial protease substrates in other host niches and provide omics-scale insight into the role of the V8 protease in S. aureus pathogenesis. S. aureus-secreted proteases are central to disease causation, but the discovery of their host substrates has been limited. Frey et al. use N-terminomic approaches to uncover human serum targets of the V8 protease that are from virulence-relevant processes such as the host inflammatory network and nutrient sequestration.
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Affiliation(s)
- Andrew Michael Frey
- Department of Cell Biology, Microbiology & Molecular Biology, University of South Florida, Tampa, FL 33620, USA
| | - Dale Chaput
- Department of Cell Biology, Microbiology & Molecular Biology, University of South Florida, Tampa, FL 33620, USA
| | - Lindsey Neil Shaw
- Department of Cell Biology, Microbiology & Molecular Biology, University of South Florida, Tampa, FL 33620, USA.
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Spence MA, Mortimer MD, Buckle AM, Minh BQ, Jackson CJ. A Comprehensive Phylogenetic Analysis of the Serpin Superfamily. Mol Biol Evol 2021; 38:2915-2929. [PMID: 33744972 PMCID: PMC8233489 DOI: 10.1093/molbev/msab081] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Serine protease inhibitors (serpins) are found in all kingdoms of life and play essential roles in multiple physiological processes. Owing to the diversity of the superfamily, phylogenetic analysis is challenging and prokaryotic serpins have been speculated to have been acquired from Metazoa through horizontal gene transfer due to their unexpectedly high homology. Here, we have leveraged a structural alignment of diverse serpins to generate a comprehensive 6,000-sequence phylogeny that encompasses serpins from all kingdoms of life. We show that in addition to a central “hub” of highly conserved serpins, there has been extensive diversification of the superfamily into many novel functional clades. Our analysis indicates that the hub proteins are ancient and are similar because of convergent evolution, rather than the alternative hypothesis of horizontal gene transfer. This work clarifies longstanding questions in the evolution of serpins and provides new directions for research in the field of serpin biology.
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Affiliation(s)
- Matthew A Spence
- Research School of Chemistry, Australian National University, Canberra, ACT, Australia
| | - Matthew D Mortimer
- Research School of Chemistry, Australian National University, Canberra, ACT, Australia
| | - Ashley M Buckle
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, VIC, Australia
| | - Bui Quang Minh
- Research School of Computing and Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Colin J Jackson
- Research School of Chemistry, Australian National University, Canberra, ACT, Australia.,Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, Research School of Chemistry, Australian National University, Canberra, ACT, Australia.,Australian Research Council Centre of Excellence in Synthetic Biology, Research School of Chemistry, Australian National University, Canberra, ACT, Australia
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6
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Tušar L, Usenik A, Turk B, Turk D. Mechanisms Applied by Protein Inhibitors to Inhibit Cysteine Proteases. Int J Mol Sci 2021; 22:997. [PMID: 33498210 PMCID: PMC7863939 DOI: 10.3390/ijms22030997] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/13/2021] [Accepted: 01/16/2021] [Indexed: 02/07/2023] Open
Abstract
Protein inhibitors of proteases are an important tool of nature to regulate and control proteolysis in living organisms under physiological and pathological conditions. In this review, we analyzed the mechanisms of inhibition of cysteine proteases on the basis of structural information and compiled kinetic data. The gathered structural data indicate that the protein fold is not a major obstacle for the evolution of a protease inhibitor. It appears that nature can convert almost any starting fold into an inhibitor of a protease. In addition, there appears to be no general rule governing the inhibitory mechanism. The structural data make it clear that the "lock and key" mechanism is a historical concept with limited validity. However, the analysis suggests that the shape of the active site cleft of proteases imposes some restraints. When the S1 binding site is shaped as a pocket buried in the structure of protease, inhibitors can apply substrate-like binding mechanisms. In contrast, when the S1 binding site is in part exposed to solvent, the substrate-like inhibition cannot be employed. It appears that all proteases, with the exception of papain-like proteases, belong to the first group of proteases. Finally, we show a number of examples and provide hints on how to engineer protein inhibitors.
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Affiliation(s)
- Livija Tušar
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; (L.T.); (A.U.); (B.T.)
- Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins (CIPKeBiP), Jamova cesta 39, 1000 Ljubljana, Slovenia
| | - Aleksandra Usenik
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; (L.T.); (A.U.); (B.T.)
- Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins (CIPKeBiP), Jamova cesta 39, 1000 Ljubljana, Slovenia
| | - Boris Turk
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; (L.T.); (A.U.); (B.T.)
- Faculty of Chemistry, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
- Institute of Regenerative Medicine, I.M. Sechenov First Moscow State Medical University, Bol’shaya Pirogovskaya Ulitsa, 19c1, 119146 Moscow, Russia
| | - Dušan Turk
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia; (L.T.); (A.U.); (B.T.)
- Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins (CIPKeBiP), Jamova cesta 39, 1000 Ljubljana, Slovenia
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7
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Jairajpuri M, Ansari S. Using serpins cysteine protease cross-specificity to possibly trap SARS-CoV-2 Mpro with reactive center loop chimera. Clin Sci (Lond) 2020; 134:2235-2241. [PMID: 32869854 PMCID: PMC7463295 DOI: 10.1042/cs20200767] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/10/2020] [Accepted: 08/19/2020] [Indexed: 01/20/2023]
Abstract
Human serine protease inhibitors (serpins) are the main inhibitors of serine proteases, but some of them also have the capability to effectively inhibit cysteine proteases. Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) main protease (Mpro) is a chymotrypsin-type cysteine protease that is needed to produce functional proteins essential for virus replication and transcription. Serpin traps its target proteases by presenting a reactive center loop (RCL) as protease-specific cleavage site, resulting in protease inactivation. Mpro target sites with its active site serine and other flanking residues can possibly interact with serpins. Alternatively, RCL cleavage site of serpins with known evidence of inhibition of cysteine proteases can be replaced by Mpro target site to make chimeric proteins. Purified chimeric serpin can possibly inhibit Mpro that can be assessed indirectly by observing the decrease in ability of Mpro to cleave its chromogenic substrate. Chimeric serpins with best interaction and active site binding and with ability to form 1:1 serpin-Mpro complex in human plasma can be assessed by using SDS/PAGE and Western blot analysis with serpin antibody. Trapping SARS-CoV-2 Mpro cysteine protease using cross-class serpin cysteine protease inhibition activity is a novel idea with significant therapeutic potential.
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Affiliation(s)
| | - Shoyab Ansari
- Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India
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8
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Galdino ACM, de Oliveira MP, Ramalho TC, de Castro AA, Branquinha MH, Santos ALS. Anti-Virulence Strategy against the Multidrug-Resistant Bacterial Pathogen Pseudomonas aeruginosa: Pseudolysin (Elastase B) as a Potential Druggable Target. Curr Protein Pept Sci 2019; 20:471-487. [PMID: 30727891 DOI: 10.2174/1389203720666190207100415] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/26/2019] [Accepted: 01/31/2019] [Indexed: 11/22/2022]
Abstract
Pseudomonas aeruginosa is a non-fermentative, gram-negative bacterium that is one of the most common pathogens responsible for hospital-acquired infections worldwide. The management of the infections caused by P. aeruginosa represents a huge challenge in the healthcare settings due to the increased emergence of resistant isolates, some of them resistant to all the currently available antimicrobials, which results in elevated morbimortality rates. Consequently, the development of new therapeutic strategies against multidrug-resistant P. aeruginosa is urgent and needful. P. aeruginosa is wellrecognized for its extreme genetic versatility and its ability to produce a lush variety of virulence factors. In this context, pseudolysin (or elastase B) outstands as a pivotal virulence attribute during the infectious process, playing multifunctional roles in different aspects of the pathogen-host interaction. This protein is a 33-kDa neutral zinc-dependent metallopeptidase that is the most abundant peptidase found in pseudomonal secretions, which contributes to the invasiveness of P. aeruginosa due to its ability to cleave several extracellular matrix proteins and to disrupt the basolateral intercellular junctions present in the host tissues. Moreover, pseudolysin makes P. aeruginosa able to overcome host defenses by the hydrolysis of many immunologically relevant molecules, including antibodies and complement components. The attenuation of this striking peptidase therefore emerges as an alternative and promising antivirulence strategy to combat antibiotic-refractory infections caused by P. aeruginosa. The anti-virulence approach aims to disarm the P. aeruginosa infective arsenal by inhibiting the expression/activity of bacterial virulence factors in order to reduce the invasiveness of P. aeruginosa, avoiding the emergence of resistance since the proliferation is not affected. This review summarizes the most relevant features of pseudolysin and highlights this enzyme as a promising target for the development of new anti-virulence compounds.
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Affiliation(s)
- Anna Clara M Galdino
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Goes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Programa de Pós-Graduação em Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Matheus P de Oliveira
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA, United States
| | - Teodorico C Ramalho
- Departamento de Quimica, Universidade Federal de Lavras, Minas Gerais, Brazil
| | | | - Marta H Branquinha
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Goes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - André L S Santos
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Goes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Programa de Pós-Graduação em Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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9
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Akermi N, Mkaouar H, Kriaa A, Jablaoui A, Soussou S, Gargouri A, Coleman AW, Perret F, Maguin E, Rhimi M. para-Sulphonato-calix[n]arene capped silver nanoparticles challenge the catalytic efficiency and the stability of a novel human gut serine protease inhibitor. Chem Commun (Camb) 2019; 55:8935-8938. [PMID: 31286126 DOI: 10.1039/c9cc03183a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The Eubacterium saburreum serine protease inhibitor from the human gut microbiota inhibits the eukaryotic pancreatic elastase associated with acute pancreatitis. Interestingly, the inhibition efficiency and stability are markedly increased by the para-sulphonato-calix[8]arene capped silver nanoparticles. Moreover, this enzyme is distinguishable by its high inhibitory effect at broad pH range between 2-10 and temperatures from 10 to 40 °C, in the presence of para-sulphonato-calix[8]arene capped silver nanoparticles the enzyme remains active even at 70 °C.
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Affiliation(s)
- Nizar Akermi
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France.
| | - Hela Mkaouar
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France.
| | - Aicha Kriaa
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France.
| | - Amin Jablaoui
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France.
| | - Souha Soussou
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France.
| | - Ali Gargouri
- Laboratory of Molecular Biology of Eukaryotes, Center of Biotechnology of Sfax, University of Sfax, 3038, Sfax, Tunisia
| | | | - Florent Perret
- Univ Lyon, Université Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, UMR 5246 CNRS, F-69622, Villeurbanne, France
| | - Emmanuelle Maguin
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France.
| | - Moez Rhimi
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France.
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10
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Alam B, Biswas S. Inhibition of Plasmodium falciparum cysteine protease falcipain-2 by a human cross-class inhibitor serpinB3: A mechanistic insight. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:854-865. [PMID: 31247344 DOI: 10.1016/j.bbapap.2019.06.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 05/21/2019] [Accepted: 06/20/2019] [Indexed: 11/16/2022]
Abstract
Falcipain-2(FP2), a cysteine protease from Plasmodium falciparum, cleaves host erythrocyte hemoglobin and specific membrane skeleton components during the parasite life cycle. Therefore its inhibition has been considered as an attractive approach to combat the disease. SerpinB3 (SPB3) belongs to the ovalbumin-serpin family and is a potent cross-class inhibitor of cysteine cathepsins L, K, S and papain. This study explored the possibility of inhibition of FP2 by SPB3. It turned out that general proteolytic activities as well as specific hemoglobinolytic activity of FP2 have been inhibited by SPB3. Furthermore, studies have been designed to investigate and characterize the mechanism of inhibition in comparison with proteases Cathepsin L (CTSL) and papain. The Ki value of inhibition for FP2, measured against its specific substrate (VLK-pNA), is 338.11 nM and stoichiometry (I/E ratio) of inhibition is 1. These values are comparable to CTSL and papain. Analytical gel filtration profile and CD spectroscopy data confirm FP2-SPB3 complex formation. Our studies revealed that interaction of SPB3 with FP2 is non-covalent type like that of CTSL and papain but unlike other serine protease-inhibiting serpins. An in-silico docking and simulation study have been performed with FP2 as well as CTSL and results suggest different binding mode for FP2 and CTSL, though both the complexes are stable with significant contribution from electrostatic energy of interaction. We further showed a disease state mutant SPB3-Gly351Ala performed better anti-protease activity against FP2. This study, for the first time, has shown a serpin family inhibitor from human could efficiently inhibit activity of FP2.
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Affiliation(s)
- Benazir Alam
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064, India
| | - Sampa Biswas
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064, India; Homi Bhaba National Institute, Anushaktinagar, Mumbai 400 094, India.
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11
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Nguyen MT, Saising J, Tribelli PM, Nega M, Diene SM, François P, Schrenzel J, Spröer C, Bunk B, Ebner P, Hertlein T, Kumari N, Härtner T, Wistuba D, Voravuthikunchai SP, Mäder U, Ohlsen K, Götz F. Inactivation of farR Causes High Rhodomyrtone Resistance and Increased Pathogenicity in Staphylococcus aureus. Front Microbiol 2019; 10:1157. [PMID: 31191485 PMCID: PMC6547885 DOI: 10.3389/fmicb.2019.01157] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 05/07/2019] [Indexed: 12/22/2022] Open
Abstract
Rhodomyrtone (Rom) is an acylphloroglucinol antibiotic originally isolated from leaves of Rhodomyrtus tomentosa. Rom targets the bacterial membrane and is active against a wide range of Gram-positive bacteria but the exact mode of action remains obscure. Here we isolated and characterized a spontaneous Rom-resistant mutant from the model strain Staphylococcus aureus HG001 (RomR) to learn more about the resistance mechanism. We showed that Rom-resistance is based on a single point mutation in the coding region of farR [regulator of fatty acid (FA) resistance] that causes an amino acid change from Cys to Arg at position 116 in FarR, that affects FarR activity. Comparative transcriptome analysis revealed that mutated farR affects transcription of many genes in distinct pathways. FarR represses for example the expression of its own gene (farR), its flanking gene farE (effector of FA resistance), and other global regulators such as agr and sarA. All these genes were consequently upregulated in the RomR clone. Particularly the upregulation of agr and sarA leads to increased expression of virulence genes rendering the RomR clone more cytotoxic and more pathogenic in a mouse infection model. The Rom-resistance is largely due to the de-repression of farE. FarE is described as an efflux pump for linoleic and arachidonic acids. We observed an increased release of lipids in the RomR clone compared to its parental strain HG001. If farE is deleted in the RomR clone, or, if native farR is expressed in the RomR strain, the corresponding strains become hypersensitive to Rom. Overall, we show here that the high Rom-resistance is mediated by overexpression of farE in the RomR clone, that FarR is an important regulator, and that the point mutation in farR (RomR clone) makes the clone hyper-virulent.
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Affiliation(s)
- Minh-Thu Nguyen
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany.,Federal Regulatory Agency for Vaccines and Biomedicines, Paul Ehrlich Institute, Langen, Germany
| | - Jongkon Saising
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany.,School of Health Science, Mae Fah Luang University, Chiang Rai, Thailand
| | - Paula Maria Tribelli
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany.,Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales - Universidad de Buenos Aires, IQUIBICEN-CONICET, Buenos Aires, Argentina
| | - Mulugeta Nega
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Seydina M Diene
- Genomic Research Laboratory, Service of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Patrice François
- Genomic Research Laboratory, Service of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Jacques Schrenzel
- Genomic Research Laboratory, Service of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Cathrin Spröer
- Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Boyke Bunk
- Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Patrick Ebner
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Tobias Hertlein
- Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Nimerta Kumari
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Thomas Härtner
- Microbiology/Biotechnology, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Dorothee Wistuba
- Institute for Organic Chemistry, University of Tübingen, Tübingen, Germany
| | - Supayang P Voravuthikunchai
- Department of Microbiology, Natural Product Centre of Excellence, Prince of Songkla University, Hat Yai, Thailand
| | - Ulrike Mäder
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Knut Ohlsen
- Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Friedrich Götz
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
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12
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Development of Chemical Tools to Monitor Human Kallikrein 13 (KLK13) Activity. Int J Mol Sci 2019; 20:ijms20071557. [PMID: 30925705 PMCID: PMC6479877 DOI: 10.3390/ijms20071557] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/14/2019] [Accepted: 03/25/2019] [Indexed: 12/17/2022] Open
Abstract
Kallikrein 13 (KLK13) was first identified as an enzyme that is downregulated in a subset of breast tumors. This serine protease has since been implicated in a number of pathological processes including ovarian, lung and gastric cancers. Here we report the design, synthesis and deconvolution of libraries of internally quenched fluorogenic peptide substrates to determine the specificity of substrate binding subsites of KLK13 in prime and non-prime regions (according to the Schechter and Berger convention). The substrate with the consensus sequential motive ABZ-Val-Arg-Phe-Arg-ANB-NH2 demonstrated selectivity towards KLK13 and was successfully converted into an activity-based probe by the incorporation of a chloromethylketone warhead and biotin bait. The compounds described may serve as suitable tools to detect KLK13 activity in diverse biological samples, as exemplified by overexpression experiments and targeted labeling of KLK13 in cell lysates and saliva. In addition, we describe the development of selective activity-based probes targeting KLK13, to our knowledge the first tool to analyze the presence of the active enzyme in biological samples.
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13
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Tam K, Torres VJ. Staphylococcus aureus Secreted Toxins and Extracellular Enzymes. Microbiol Spectr 2019; 7:10.1128/microbiolspec.GPP3-0039-2018. [PMID: 30873936 PMCID: PMC6422052 DOI: 10.1128/microbiolspec.gpp3-0039-2018] [Citation(s) in RCA: 192] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Indexed: 02/06/2023] Open
Abstract
Staphylococcus aureus is a formidable pathogen capable of causing infections in different sites of the body in a variety of vertebrate animals, including humans and livestock. A major contribution to the success of S. aureus as a pathogen is the plethora of virulence factors that manipulate the host's innate and adaptive immune responses. Many of these immune modulating virulence factors are secreted toxins, cofactors for activating host zymogens, and exoenzymes. Secreted toxins such as pore-forming toxins and superantigens are highly inflammatory and can cause leukocyte cell death by cytolysis and clonal deletion, respectively. Coagulases and staphylokinases are cofactors that hijack the host's coagulation system. Exoenzymes, including nucleases and proteases, cleave and inactivate various immune defense and surveillance molecules, such as complement factors, antimicrobial peptides, and surface receptors that are important for leukocyte chemotaxis. Additionally, some of these secreted toxins and exoenzymes can cause disruption of endothelial and epithelial barriers through cell lysis and cleavage of junction proteins. A unique feature when examining the repertoire of S. aureus secreted virulence factors is the apparent functional redundancy exhibited by the majority of the toxins and exoenzymes. However, closer examination of each virulence factor revealed that each has unique properties that have important functional consequences. This chapter provides a brief overview of our current understanding of the major secreted virulence factors critical for S. aureus pathogenesis.
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Affiliation(s)
- Kayan Tam
- Department of Microbiology, New York University School of Medicine, Alexandria Center for Life Science, New York, NY 10016
| | - Victor J Torres
- Department of Microbiology, New York University School of Medicine, Alexandria Center for Life Science, New York, NY 10016
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14
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Carrera M, Böhme K, Gallardo JM, Barros-Velázquez J, Cañas B, Calo-Mata P. Characterization of Foodborne Strains of Staphylococcus aureus by Shotgun Proteomics: Functional Networks, Virulence Factors and Species-Specific Peptide Biomarkers. Front Microbiol 2017; 8:2458. [PMID: 29312172 PMCID: PMC5732212 DOI: 10.3389/fmicb.2017.02458] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/27/2017] [Indexed: 11/13/2022] Open
Abstract
In the present work, we applied a shotgun proteomics approach for the fast and easy characterization of 20 different foodborne strains of Staphylococcus aureus (S. aureus), one of the most recognized foodborne pathogenic bacteria. A total of 644 non-redundant proteins were identified and analyzed via an easy and rapid protein sample preparation procedure. The results allowed the differentiation of several proteome datasets from the different strains (common, accessory, and unique datasets), which were used to determine relevant functional pathways and differentiate the strains into different Euclidean hierarchical clusters. Moreover, a predicted protein-protein interaction network of the foodborne S. aureus strains was created. The whole confidence network contains 77 nodes and 769 interactions. Most of the identified proteins were surface-associated proteins that were related to pathways and networks of energy, lipid metabolism and virulence. Twenty-seven virulence factors were identified, and most of them corresponded to autolysins, N-acetylmuramoyl-L-alanine amidases, phenol-soluble modulins, extracellular fibrinogen-binding proteins and virulence factor EsxA. Potential species-specific peptide biomarkers were screened. Twenty-one species-specific peptide biomarkers, belonging to eight different proteins (nickel-ABC transporter, N-acetylmuramoyl-L-alanine amidase, autolysin, clumping factor A, gram-positive signal peptide YSIRK, cysteine protease/staphopain, transcriptional regulator MarR, and transcriptional regulator Sar-A), were proposed to identify S. aureus. These results constitute the first major dataset of peptides and proteins of foodborne S. aureus strains. This repository may be useful for further studies, for the development of new therapeutic treatments for S. aureus food intoxications and for microbial source-tracking in foodstuffs.
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Affiliation(s)
- Mónica Carrera
- Department of Food Technology, Spanish National Research Council, Marine Research Institute, Vigo, Spain
| | - Karola Böhme
- Department of Analytical Chemistry, Nutrition and Food Science, School of Veterinary Sciences, University of Santiago de Compostela, Lugo, Spain
| | - José M. Gallardo
- Department of Food Technology, Spanish National Research Council, Marine Research Institute, Vigo, Spain
| | - Jorge Barros-Velázquez
- Department of Analytical Chemistry, Nutrition and Food Science, School of Veterinary Sciences, University of Santiago de Compostela, Lugo, Spain
| | - Benito Cañas
- Department of Analytical Chemistry, Complutense University of Madrid, Madrid, Spain
| | - Pilar Calo-Mata
- Department of Analytical Chemistry, Nutrition and Food Science, School of Veterinary Sciences, University of Santiago de Compostela, Lugo, Spain
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15
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Ksiazek M, Mizgalska D, Enghild JJ, Scavenius C, Thogersen IB, Potempa J. Miropin, a novel bacterial serpin from the periodontopathogen Tannerella forsythia, inhibits a broad range of proteases by using different peptide bonds within the reactive center loop. J Biol Chem 2014; 290:658-70. [PMID: 25389290 DOI: 10.1074/jbc.m114.601716] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
All prokaryotic genes encoding putative serpins identified to date are found in environmental and commensal microorganisms, and only very few prokaryotic serpins have been investigated from a mechanistic standpoint. Herein, we characterized a novel serpin (miropin) from the human pathogen Tannerella forsythia, a bacterium implicated in initiation and progression of human periodontitis. In contrast to other serpins, miropin efficiently inhibited a broad range of proteases (neutrophil and pancreatic elastases, cathepsin G, subtilisin, and trypsin) with a stoichiometry of inhibition of around 3 and second-order association rate constants that ranged from 2.7 × 10(4) (cathepsin G) to 7.1 × 10(5) m(-1)s(-1) (subtilisin). Inhibition was associated with the formation of complexes that were stable during SDS-PAGE. The unusually broad specificity of miropin for target proteases is achieved through different active sites within the reactive center loop upstream of the P1-P1' site, which was predicted from an alignment of the primary structure of miropin with those of well studied human and prokaryotic serpins. Thus, miropin is unique among inhibitory serpins, and it has apparently evolved the ability to inhibit a multitude of proteases at the expense of a high stoichiometry of inhibition and a low association rate constant. These characteristics suggest that miropin arose as an adaptation to the highly proteolytic environment of subgingival plaque, which is exposed continually to an array of host proteases in the inflammatory exudate. In such an environment, miropin may function as an important virulence factor by protecting bacterium from the destructive activity of neutrophil serine proteases. Alternatively, it may act as a housekeeping protein that regulates the activity of endogenous T. forsythia serine proteases.
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Affiliation(s)
- Miroslaw Ksiazek
- From the Department of Microbiology, Faculty of Biochemistry, Biophysics, and Biotechnology, Jagiellonian University, 30-387 Krakow, Poland,
| | - Danuta Mizgalska
- From the Department of Microbiology, Faculty of Biochemistry, Biophysics, and Biotechnology, Jagiellonian University, 30-387 Krakow, Poland
| | - Jan J Enghild
- Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO) at the Department of Molecular Biology and Genetics, Aarhus University, Aarhus DK-8000, Denmark, and
| | - Carsten Scavenius
- Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO) at the Department of Molecular Biology and Genetics, Aarhus University, Aarhus DK-8000, Denmark, and
| | - Ida B Thogersen
- Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO) at the Department of Molecular Biology and Genetics, Aarhus University, Aarhus DK-8000, Denmark, and
| | - Jan Potempa
- From the Department of Microbiology, Faculty of Biochemistry, Biophysics, and Biotechnology, Jagiellonian University, 30-387 Krakow, Poland, Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky 40202
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16
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Gomes S, Marques PI, Matthiesen R, Seixas S. Adaptive evolution and divergence of SERPINB3: a young duplicate in great Apes. PLoS One 2014; 9:e104935. [PMID: 25133778 PMCID: PMC4136820 DOI: 10.1371/journal.pone.0104935] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 07/14/2014] [Indexed: 11/23/2022] Open
Abstract
A series of duplication events led to an expansion of clade B Serine Protease Inhibitors (SERPIN), currently displaying a large repertoire of functions in vertebrates. Accordingly, the recent duplicates SERPINB3 and B4 located in human 18q21.3 SERPIN cluster control the activity of different cysteine and serine proteases, respectively. Here, we aim to assess SERPINB3 and B4 coevolution with their target proteases in order to understand the evolutionary forces shaping the accelerated divergence of these duplicates. Phylogenetic analysis of primate sequences placed the duplication event in a Hominoidae ancestor (∼30 Mya) and the emergence of SERPINB3 in Homininae (∼9 Mya). We detected evidence of strong positive selection throughout SERPINB4/B3 primate tree and target proteases, cathepsin L2 (CTSL2) and G (CTSG) and chymase (CMA1). Specifically, in the Homininae clade a perfect match was observed between the adaptive evolution of SERPINB3 and cathepsin S (CTSS) and most of sites under positive selection were located at the inhibitor/protease interface. Altogether our results seem to favour a coevolution hypothesis for SERPINB3, CTSS and CTSL2 and for SERPINB4 and CTSG and CMA1. A scenario of an accelerated evolution driven by host-pathogen interactions is also possible since SERPINB3/B4 are potent inhibitors of exogenous proteases, released by infectious agents. Finally, similar patterns of expression and the sharing of many regulatory motifs suggest neofunctionalization as the best fitted model of the functional divergence of SERPINB3 and B4 duplicates.
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Affiliation(s)
- Sílvia Gomes
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal
- * E-mail: (SG); (SS)
| | - Patrícia I. Marques
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal
- Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Rune Matthiesen
- National Health Institute Doutor Ricardo Jorge (INSA), Lisboa, Portugal
| | - Susana Seixas
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal
- * E-mail: (SG); (SS)
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Vale PF, Fenton A, Brown SP. Limiting damage during infection: lessons from infection tolerance for novel therapeutics. PLoS Biol 2014; 12:e1001769. [PMID: 24465177 PMCID: PMC3897360 DOI: 10.1371/journal.pbio.1001769] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In the field of infectious disease control, novel therapies are focusing on reducing illness caused by pathogens rather than on reducing the pathogen burden itself. Here, Vale and colleagues highlight some potential consequences of such therapeutics for pathogen spread and evolution.
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Affiliation(s)
- Pedro F. Vale
- Centre for Immunity, Infection, and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail:
| | - Andy Fenton
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Sam P. Brown
- Centre for Immunity, Infection, and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
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18
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Kantyka T, Potempa J. Human SCCA serpins inhibit staphylococcal cysteine proteases by forming classic "serpin-like" covalent complexes. Methods Enzymol 2011; 499:331-45. [PMID: 21683261 DOI: 10.1016/b978-0-12-386471-0.00016-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Proteolytic enzymes secreted by Staphylococcus aureus are considered important virulence factors. Here, we present data showing that staphylococci-derived cysteine proteases (staphopains) are efficiently inhibited by squamous cell carcinoma antigen 1 (SCCA1), a serpin abundant on the epithelial surfaces. The high association rate constant (k(ass)) for inhibitory complex formation (1.9 × 10⁴ and 5.8 ×10⁴ M⁻¹ s⁻¹ for staphopain A and staphopain B interaction with SCCA1, respectively) argues that SCCA1 can restrain staphopain activity in vivo at epithelial sites colonized by S. aureus. The mechanism of staphopain inhibition by SCCA1 is apparently the same as for serpin interaction with target serine proteases. The formation of a covalent complex results in cleavage of the SCCA1 reactive site peptide bond, and it is associated with the release of the C-terminal peptide of 37 amino acid residues from the serpin. Significantly, the SCCA1 reactive site closely resembles a motif in the reactive site loop of natural S. aureus-derived inhibitors of the staphopains (staphostatins). Taking into account that SCCA1 is predominantly expressed in epithelial tissues, including respiratory pathways, hair follicles and skin [Kato, H. (1996). Expression and function of squamous cell carcinoma antigen. Anticancer Res.16, 2149-2153.], all of which are regularly colonized by S. aureus, the physiological relevance of SCCA1-staphopain B interaction as a defense mechanism seems to be very well substantiated.
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Affiliation(s)
- Tomasz Kantyka
- Department of Microbiology, Faculty of Biochemistry, Biophysics, and Biotechnology, Jagiellonian University, Krakow, Poland
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