1
|
Rooholamini Z, Dianat-Moghadam H, Esmaeilifallah M, Khanahmad H. From classical approaches to new developments in genetic engineering of live attenuated vaccine against cutaneous leishmaniasis: potential and immunization. Front Public Health 2024; 12:1382996. [PMID: 39035184 PMCID: PMC11257927 DOI: 10.3389/fpubh.2024.1382996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 06/07/2024] [Indexed: 07/23/2024] Open
Abstract
Despite the development of a vaccine against cutaneous leishmaniasis in preclinical and clinical studies, we still do not have a safe and effective vaccine for human use. Given this situation, the search for a new prophylactic alternative to control leishmaniasis should be a global priority. A first-generation vaccine strategy-leishmanization, in which live Leishmania major parasites are inoculated into the skin to protect against reinfection, is taking advantage of this situation. Live attenuated Leishmania vaccine candidates are promising alternatives due to their robust protective immune responses. Importantly, they do not cause disease and could provide long-term protection following challenges with a virulent strain. In addition to physical and chemical methods, genetic tools, including the Cre-loxP system, have enabled the selection of safer null mutant live attenuated Leishmania parasites obtained by gene disruption. This was followed by the discovery and introduction of CRISPR/Cas-based gene editing tools, which can be easily and precisely used to modify genes. Here, we briefly review the immunopathology of L. major parasites and then present the classical methods and their limitations for the production of live attenuated vaccines. We then discuss the potential of current genetic engineering tools to generate live attenuated vaccine strains by targeting key genes involved in L. major pathogenesis and then discuss their discovery and implications for immune responses to control leishmaniasis.
Collapse
Affiliation(s)
- Zahra Rooholamini
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hassan Dianat-Moghadam
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
- Pediatric Inherited Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahsa Esmaeilifallah
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
- Department of Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hossein Khanahmad
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
2
|
Moreira POL, Nogueira PM, Monte-Neto RL. Next-Generation Leishmanization: Revisiting Molecular Targets for Selecting Genetically Engineered Live-Attenuated Leishmania. Microorganisms 2023; 11:microorganisms11041043. [PMID: 37110466 PMCID: PMC10145799 DOI: 10.3390/microorganisms11041043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 04/07/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
Despite decades of research devoted to finding a vaccine against leishmaniasis, we are still lacking a safe and effective vaccine for humans. Given this scenario, the search for a new prophylaxis alternative for controlling leishmaniasis should be a global priority. Inspired by leishmanization-a first generation vaccine strategy where live L. major parasites are inoculated in the skin to protect against reinfection-live-attenuated Leishmania vaccine candidates are promising alternatives due to their robust elicited protective immune response. In addition, they do not cause disease and could provide long-term protection upon challenge with a virulent strain. The discovery of a precise and easy way to perform CRISPR/Cas-based gene editing allowed the selection of safer null mutant live-attenuated Leishmania parasites obtained by gene disruption. Here, we revisited molecular targets associated with the selection of live-attenuated vaccinal strains, discussing their function, their limiting factors and the ideal candidate for the next generation of genetically engineered live-attenuated Leishmania vaccines to control leishmaniasis.
Collapse
Affiliation(s)
- Paulo O L Moreira
- Biotechnology Applied to Pathogens (BAP), Instituto René Rachou, Fundação Oswaldo Cruz, Fiocruz Minas, Belo Horizonte 30190-009, Brazil
| | - Paula M Nogueira
- Biotechnology Applied to Pathogens (BAP), Instituto René Rachou, Fundação Oswaldo Cruz, Fiocruz Minas, Belo Horizonte 30190-009, Brazil
| | - Rubens L Monte-Neto
- Biotechnology Applied to Pathogens (BAP), Instituto René Rachou, Fundação Oswaldo Cruz, Fiocruz Minas, Belo Horizonte 30190-009, Brazil
| |
Collapse
|
3
|
Yi F, Gu W, Li J, Chen J, Hu L, Cui Y, Zhao H, Guo Y, Lai J, Song W. Miniature Seed6, encoding an endoplasmic reticulum signal peptidase, is critical in seed development. PLANT PHYSIOLOGY 2021; 185:985-1001. [PMID: 33793873 PMCID: PMC8133640 DOI: 10.1093/plphys/kiaa060] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 11/15/2020] [Indexed: 05/15/2023]
Abstract
Endoplasmic reticulum (ER) type I signal peptidases (ER SPases I) are vital proteases that cleave signal peptides from secreted proteins. However, the specific function of ER SPase I in plants has not been genetically characterized, and the substrate is largely unknown. Here, we report the identification of a maize (Zea mays) miniature seed6 (mn6) mutant. The loss-of-function mn6 mutant exhibited severely reduced endosperm size. Map-based cloning and molecular characterization indicated that Mn6 is an S26-family ER SPase I, with Gly102 (box E) in Mn6 critical for protein function during processing. Mass spectrometric and immunoprecipitation analyses revealed that Mn6 is predominantly involved in processing carbohydrate synthesis-related proteins, including the cell wall invertase miniature seed1 (Mn1), which is specifically expressed in the basal endosperm transfer layer. RNA and protein expression levels of Mn1 were both significantly downregulated in the mn6 mutant. Due to the significant reduction in cell wall invertase activity in the transfer cell layer, mutation of Mn6 caused dramatic defects in endosperm development. These results suggest that proper maturation of Mn1 by Mn6 may be a crucial step for proper seed filling and maize development.
Collapse
Affiliation(s)
- Fei Yi
- State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing, 100193, P. R. China
- Engineering Research Center of Plant Growth Regulator, Ministry of Education & College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, P. R. China
| | - Wei Gu
- State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing, 100193, P. R. China
| | - Jianfang Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, P. R. China
| | - Jian Chen
- State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing, 100193, P. R. China
| | - Li Hu
- State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing, 100193, P. R. China
| | - Yang Cui
- State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing, 100193, P. R. China
| | - Haiming Zhao
- State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing, 100193, P. R. China
| | - Yan Guo
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, P. R. China
| | - Jinsheng Lai
- State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing, 100193, P. R. China
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing, 100193, P. R. China
| | - Weibin Song
- State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center, Department of Plant Genetics and Breeding, China Agricultural University, Beijing, 100193, P. R. China
- Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing, 100193, P. R. China
- Author for communication:
| |
Collapse
|
4
|
Sezavar M, Sharifi I, Ghasemi Nejad Almani P, Kazemi B, Davoudi N, Salari S, Salarkia E, Khosravi A, Bamorovat M. The potential therapeutic role of PTR1 gene in non-healing anthroponotic cutaneous leishmaniasis due to Leishmania tropica. J Clin Lab Anal 2021; 35:e23670. [PMID: 33283321 PMCID: PMC7957997 DOI: 10.1002/jcla.23670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 11/06/2020] [Accepted: 11/12/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Drug resistance is a common phenomenon frequently observed in countries where leishmaniasis is endemic. Due to the production of the pteridine reductase enzyme (PTR1), drugs lose their efficacy, and consequently, the patient becomes unresponsive to treatment. This study aimed to compare the in vitro effect of meglumine antimoniate (MA) on non- healing Leishmania tropica isolates and on MA transfected non-healing one to PTR1. METHODS Two non-healing and one healing isolates of L. tropica were collected from patients who received two courses or one cycle of intralesional MA along with biweekly liquid nitrogen cryotherapy or systemic treatment alone, respectively. After confirmation of L. tropica isolates by polymerase chain reaction (PCR), the recombinant plasmid pcDNA-rPTR (antisense) was transfected via electroporation and cultured on M199. Isolates in form of promastigotes were treated with different concentrations of MA and read using an enzyme-linked immunosorbent assay (ELISA) reader and the half inhibitory concentration (IC50 ) value was calculated. The amastigotes were grown in mouse macrophages and were similarly treated with various concentrations of MA. The culture glass slides were stained, and the mean number of intramacrophage amastigotes and infected macrophages were assessed in triplicate for both stages. RESULTS All three transfected isolates displayed a reduction in optical density compared with the promastigotes in respective isolates, although there was no significant difference between non-healing and healing isolates. In contrast, in the clinical form (amastigotes), there was a significant difference between non-healing and healing isolates (p < 0.05). CONCLUSION The results indicated that the PTR1 gene reduced the efficacy of the drug, and its inhibition by antisense and could improve the treatment of non-healing cases. These findings have future implications in the prophylactic and therapeutic modality of non- healing Leishmania isolates to drug.
Collapse
Affiliation(s)
- Monireh Sezavar
- Department of Experimental SciencesFaculty of Allied medicineAlborz University of Medical SciencesKarajIran
| | - Iraj Sharifi
- Leishmaniasis Research CentreKerman University of Medical SciencesKermanIran
| | | | - Bahram Kazemi
- Cellular and Molecular Biology, Research CentreShahid Beheshti University of Medical SciencesTehranIran
- Biotechnology Department, School of Advanced Technologies in MedicineShahid Beheshti University of Medical SciencesIran
| | - Noushin Davoudi
- Department of BiotechnologyPasteur Institute of IranTehranIran
| | - Samira Salari
- Medical Mycology and Bacteriology Research CenterKerman University of Medical SciencesKermanIran
| | - Ehsan Salarkia
- Leishmaniasis Research CentreKerman University of Medical SciencesKermanIran
| | - Ahmad Khosravi
- Leishmaniasis Research CentreKerman University of Medical SciencesKermanIran
| | - Mehdi Bamorovat
- Leishmaniasis Research CentreKerman University of Medical SciencesKermanIran
| |
Collapse
|
5
|
Contreras M, Villar M, de la Fuente J. A Vaccinomics Approach for the Identification of Tick Protective Antigens for the Control of Ixodes ricinus and Dermacentor reticulatus Infestations in Companion Animals. Front Physiol 2019; 10:977. [PMID: 31417430 PMCID: PMC6681794 DOI: 10.3389/fphys.2019.00977] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 07/11/2019] [Indexed: 01/10/2023] Open
Abstract
Ticks and tick-borne pathogens affect health and welfare of companion animals worldwide, and some human tick-borne diseases are associated with exposure to domestic animals. Vaccines are the most environmentally friendly alternative to acaracides for the control of tick infestations, and to reduce the risk for tick-borne diseases affecting human and animal health. However, vaccines have not been developed or successfully implemented for most vector-borne diseases. The main limitation for the development of effective vaccines is the identification of protective antigens. To address this limitation, in this study we used an experimental approach combining vaccinomics based on transcriptomics and proteomics data with vaccination trials for the identification of tick protective antigens. The study was focused on Ixodes ricinus and Dermacentor reticulatus that infest humans, companion animals and other domestic and wild animals, and transmit disease-causing pathogens. Tick larvae and adult salivary glands were selected for analysis to target tick organs and developmental stages playing a key role during tick life cycle and pathogen infection and transmission. Two I. ricinus (heme lipoprotein and uncharacterized secreted protein) and five D. reticulatus (glypican-like protein, secreted protein involved in homophilic cell adhesion, sulfate/anion exchanger, signal peptidase complex subunit 3, and uncharacterized secreted protein) proteins were identified as the most effective protective antigens based on the criteria of vaccine E > 80%. The putative function of selected protective antigens, which are involved in different biological processes, resulted in vaccines affecting multiple tick developmental stages. These results suggested that the combination of some of these antigens might be considered to increase vaccine efficacy through antigen synergy for the control of tick infestations and potentially affecting pathogen infection and transmission. These antigens were proposed for commercial vaccine development for the control of tick infestations in companion animals, and potentially in other hosts for these tick species.
Collapse
Affiliation(s)
- Marinela Contreras
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC; CSIC-UCLM-JCCM), Ciudad Real, Spain
| | - Margarita Villar
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC; CSIC-UCLM-JCCM), Ciudad Real, Spain
| | - José de la Fuente
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC; CSIC-UCLM-JCCM), Ciudad Real, Spain
- Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK, United States
| |
Collapse
|
6
|
Leishmanicidal therapy targeted to parasite proteases. Life Sci 2019; 219:163-181. [PMID: 30641084 DOI: 10.1016/j.lfs.2019.01.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 01/07/2019] [Accepted: 01/09/2019] [Indexed: 12/31/2022]
Abstract
Leishmaniasis is considered a serious public health problem and the current available therapy has several disadvantages, which makes the search for new therapeutic targets and alternative treatments extremely necessary. In this context, this review focuses on the importance of parasite proteases as target drugs against Leishmania parasites, as a chemotherapy approach. Initially, we discuss about the current scenario for the treatment of leishmaniasis, highlighting the main drugs used and the problems related to their use. Subsequently, we describe the inhibitors of major proteases of Leishmania already discovered, such as Compound s9 (aziridine-2,3-dicarboxylate), Compound 1c (benzophenone derivative), Au2Phen (gold complex), AubipyC (gold complex), MDL 28170 (dipeptidyl aldehyde), K11777, Hirudin, diazo-acetyl norleucine methyl ester, Nelfinavir, Saquinavir, Nelfinavir, Saquinavir, Indinavir, Saquinavir, GNF5343 (azabenzoxazole), GNF6702 (azabenzoxazole), Benzamidine and TPCK. Next, we discuss the importance of the protease gene to parasite survival and the aspects of the validation of proteases as target drugs, with emphasis on gene disruption. Then, we describe novel important strategies that can be used to support the research of new antiparasitic drugs, such as molecular modeling and nanotechnology, whose main targets are parasitic proteases. And finally, we discuss possible perspectives to improve drug development. Based on all findings, proteases could be considered potential targets against leishmaniasis.
Collapse
|
7
|
Avishek K, Ahuja K, Pradhan D, Gannavaram S, Selvapandiyan A, Nakhasi HL, Salotra P. A Leishmania-specific gene upregulated at the amastigote stage is crucial for parasite survival. Parasitol Res 2018; 117:3215-3228. [DOI: 10.1007/s00436-018-6020-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 07/17/2018] [Indexed: 01/03/2023]
|
8
|
Understanding serine proteases implications on Leishmania spp lifecycle. Exp Parasitol 2018; 184:67-81. [DOI: 10.1016/j.exppara.2017.11.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 11/14/2017] [Accepted: 11/20/2017] [Indexed: 12/14/2022]
|
9
|
The role of GlcNAc-PI-de-N-acetylase gene by gene knockout through homologous recombination and its consequences on survival, growth and infectivity of Leishmania major in in vitro and in vivo conditions. Acta Trop 2016; 154:63-72. [PMID: 26571069 DOI: 10.1016/j.actatropica.2015.10.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Revised: 10/18/2015] [Accepted: 10/27/2015] [Indexed: 11/20/2022]
Abstract
At present, there are no efficacious vaccines or effective drugs against leishmaniasis; therefore new and innovative control methods are urgently required. One way to achieve this important goal is through using reverse genetic engineering to evaluate important enzymes, proteins and macromolecules. One of the most important enzymes for Glycosylphosphatidylinositol (GPI) biosynthetic pathways is GlcNAc-PI-de-N-acetylase (GPI12). The molecular constructs were cloned in Escherichia coli strain Top 10 and confirmed by molecular methods and were transfected by electroporation into Leishmania major. We demonstrated that two alleles of the GPI12 gene in L. major were successfully removed and enabling the generation of a null mutant, which supports the idea that GPI12 is not an essential gene for the growth and survival of Leishmania and the homozygous knockouts of Leishmania are able to survive. We were able to produce a mutant parasite that caused no damaged to the host. Further investigations are essential to check the safety profile in laboratory animals.
Collapse
|
10
|
Zhang W, Xia Y. ER type I signal peptidase subunit (LmSPC1) is essential for the survival of Locusta migratoria manilensis and affects moulting, feeding, reproduction and embryonic development. INSECT MOLECULAR BIOLOGY 2014; 23:269-285. [PMID: 24467622 DOI: 10.1111/imb.12080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The endoplasmic reticulum type I signal peptidase complex (ER SPC) is a conserved enzyme that cleaves the signal peptides of secretory or membrane preproteins. The deletion of this enzyme leads to the accumulation of uncleaved proteins in biomembranes and cell death. However, the physiological functions of ER SPC in insects are not fully understood. Here, a catalytic subunit gene of ER SPC, LmSPC1, was cloned from Locusta migratoria manilensis and its physiological functions were analysed by RNA interference (RNAi). The LmSPC1 open reading frame encoded a protein of 178 amino acids with all five conserved regions of signal peptidases. RNAi-mediated knockdown of LmSPC1 resulted in high mortality. Sixty-nine per cent of dead nymphs died of abnormal moulting, corresponding to decreased activity of moulting fluid protease. Moreover, insects in the RNAi group experienced a decline in food intake, and a decrease in the secretion of total protein and digestive enzymes from midgut tissues to the midgut lumen. Furthermore, the females produced fewer eggs and eggs with disrupted embryogenesis. These results indicate that LmSPC1 is required for the secretion of secretory proteins, affects physiological functions, including moulting, feeding, reproduction and embryonic development, and is essential for survival. Therefore, LmSPC1 may be a potential target for locust control.
Collapse
Affiliation(s)
- W Zhang
- Genetic Engineering Research Center, School of Life Science, Chongqing Engineering Research Center for Fungal Insecticide, The Key Laboratory of Gene Function and Expression Regulation, Chongqing University, Chongqing, China
| | | |
Collapse
|
11
|
Bhanu MK, Kendall DA. Fluorescence spectroscopy of soluble E. coli SPase I Δ2-75 reveals conformational changes in response to ligand binding. Proteins 2013; 82:596-606. [PMID: 24115229 DOI: 10.1002/prot.24429] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 08/28/2013] [Accepted: 09/10/2013] [Indexed: 11/07/2022]
Abstract
The bacterial Sec pathway is responsible for the translocation of secretory preproteins. During the later stages of transport, the membrane-embedded signal peptidase I (SPase I) cleaves the signal peptide from a preprotein. We used tryptophan fluorescence spectroscopy of a soluble, catalytically active E. coli SPase I Δ2-75 enzyme to study its dynamic conformational changes while in solution and when interacting with lipids and signal peptides. We generated four single Trp SPase I Δ2-75 mutants, W261, W284, W300, and W310. Based on fluorescence quenching experiments, W300 and W310 were found to be more solvent accessible than W261 and W284 in the absence of ligands. W300 and W310 inserted into lipids, consistent with their location at the enzyme's proposed membrane-interface region, while the solvent accessibilities of W261, W284, and W300 were modified in the presence of signal peptide, suggesting propagation of structural changes beyond the active site in response to peptide binding. The signal peptide binding affinity for the enzyme was measured via FRET experiments and the Kd determined to be 4.4 μM. The location of the peptide with respect to the enzyme was also established; this positioning is crucial for the peptide to gain access to the enzyme active site as it emerges from the translocon into the membrane bilayer. These studies reveal enzymatic structural changes required for preprotein proteolysis as it interacts with its two key partners, the signal peptide and membrane phospholipids.
Collapse
Affiliation(s)
- Meera K Bhanu
- Department of Molecular and Cell Biology, The University of Connecticut, Storrs, Connecticut, 06269
| | | |
Collapse
|
12
|
Leishmania (L.) amazonensis peptidase activities inside the living cells and in their lysates. Mol Biochem Parasitol 2012; 184:82-9. [DOI: 10.1016/j.molbiopara.2012.04.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 03/13/2012] [Accepted: 04/27/2012] [Indexed: 11/22/2022]
|
13
|
Auclair SM, Bhanu MK, Kendall DA. Signal peptidase I: cleaving the way to mature proteins. Protein Sci 2011; 21:13-25. [PMID: 22031009 DOI: 10.1002/pro.757] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 10/12/2011] [Accepted: 10/17/2011] [Indexed: 11/07/2022]
Abstract
Signal peptidase I (SPase I) is critical for the release of translocated preproteins from the membrane as they are transported from a cytoplasmic site of synthesis to extracytoplasmic locations. These proteins are synthesized with an amino-terminal extension, the signal sequence, which directs the preprotein to the Sec- or Tat-translocation pathway. Recent evidence indicates that the SPase I cleaves preproteins as they emerge from either pathway, though the steps involved are unclear. Now that the structure of many translocation pathway components has been elucidated, it is critical to determine how these components work in concert to support protein translocation and cleavage. Molecular modeling and NMR studies have provided insight on how the preprotein docks on SPase I in preparation for cleavage. This is a key area for future work since SPase I enzymes in a variety of species have now been identified and the inhibition of these enzymes by antibiotics is being pursued. The eubacterial SPase I is essential for cell viability and belongs to a unique group of serine endoproteases which utilize a Ser-Lys catalytic dyad instead of the prototypical Ser-His-Asp triad used by eukaryotes. As such, SPase I is a desirable antimicrobial target. Advances in our understanding of how the preprotein interfaces with SPase I during the final stages of translocation will facilitate future development of inhibitors that display a high efficacy against SPase I function.
Collapse
Affiliation(s)
- Sarah M Auclair
- Department of Pharmaceutical Sciences, The University of Connecticut, Storrs, CT 06269, USA
| | | | | |
Collapse
|