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Fathallah N, Elkady WM, Zahran SA, Darwish KM, Elhady SS, Elkhawas YA. Unveiling the Multifaceted Capabilities of Endophytic Aspergillus flavus Isolated from Annona squamosa Fruit Peels against Staphylococcus Isolates and HCoV 229E-In Vitro and In Silico Investigations. Pharmaceuticals (Basel) 2024; 17:656. [PMID: 38794226 PMCID: PMC11124496 DOI: 10.3390/ph17050656] [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: 04/09/2024] [Revised: 05/14/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024] Open
Abstract
Recently, there has been a surge towards searching for primitive treatment strategies to discover novel therapeutic approaches against multi-drug-resistant pathogens. Endophytes are considered unexplored yet perpetual sources of several secondary metabolites with therapeutic significance. This study aims to isolate and identify the endophytic fungi from Annona squamosa L. fruit peels using morphological, microscopical, and transcribed spacer (ITS-rDNA) sequence analysis; extract the fungus's secondary metabolites by ethyl acetate; investigate the chemical profile using UPLC/MS; and evaluate the potential antibacterial, antibiofilm, and antiviral activities. An endophytic fungus was isolated and identified as Aspergillus flavus L. from the fruit peels. The UPLC/MS revealed seven compounds with various chemical classes. The antimicrobial activity of the fungal ethyl acetate extract (FEA) was investigated against different Gram-positive and Gram-negative standard strains, in addition to resistant clinical isolates using the agar diffusion method. The CPE-inhibition assay was used to identify the potential antiviral activity of the crude fungal extract against low pathogenic human coronavirus (HCoV 229E). Selective Gram-positive antibacterial and antibiofilm activities were evident, demonstrating pronounced efficacy against both methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA). However, the extract exhibited very weak activity against Gram-negative bacterial strains. The ethyl acetate extract of Aspergillus flavus L exhibited an interesting antiviral activity with a half maximal inhibitory concentration (IC50) value of 27.2 µg/mL against HCoV 229E. Furthermore, in silico virtual molecular docking-coupled dynamics simulation highlighted the promising affinity of the identified metabolite, orienting towards three MRSA biotargets and HCoV 229E main protease as compared to reported reference inhibitors/substrates. Finally, ADME analysis was conducted to evaluate the potential oral bioavailability of the identified metabolites.
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Affiliation(s)
- Noha Fathallah
- Department of Pharmacognosy and Medicinal Plants, Faculty of Pharmacy, Future University in Egypt, Cairo 11835, Egypt;
| | - Wafaa M. Elkady
- Department of Pharmacognosy and Medicinal Plants, Faculty of Pharmacy, Future University in Egypt, Cairo 11835, Egypt;
| | - Sara A. Zahran
- Department of Microbiology and Immunology, Faculty of Pharmacy, Future University in Egypt, Cairo 11835, Egypt;
| | - Khaled M. Darwish
- Department of Medicinal Chemistry, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt;
| | - Sameh S. Elhady
- King Abdulaziz University Herbarium, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Center for Artificial Intelligence in Precision Medicines, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Yasmin A. Elkhawas
- Department of Pharmacognosy and Medicinal Plants, Faculty of Pharmacy, Future University in Egypt, Cairo 11835, Egypt;
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Eltabeeb MA, Hamed RR, El-Nabarawi MA, Teaima MH, Hamed MIA, Darwish KM, Hassan M, Abdellatif MM. Nanocomposite alginate hydrogel loaded with propranolol hydrochloride kolliphor ® based cerosomes as a repurposed platform for Methicillin-Resistant Staphylococcus aureus-(MRSA)-induced skin infection; in-vitro, ex-vivo, in-silico, and in-vivo evaluation. Drug Deliv Transl Res 2024:10.1007/s13346-024-01611-z. [PMID: 38762697 DOI: 10.1007/s13346-024-01611-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/23/2024] [Indexed: 05/20/2024]
Abstract
Nanocomposite alginate hydrogel containing Propranolol hydrochloride (PNL) cerosomes (CERs) was prepared as a repurposed remedy for topical skin Methicillin-Resistant Staphylococcus aureus (MRSA) infection. CERs were formed via an ethanol injection technique using different ceramides, Kolliphores® as a surfactant, and Didodecyldimethylammonium bromide (DDAB) as a positive charge inducer. CERs were optimized utilizing 13. 22 mixed-factorial design employing Design-Expert® software, the assessed responses were entrapment efficiency (EE%), particle size (PS), and zeta potential (ZP). The optimum CER, composed of 5 mg DDAB, ceramide VI, and Kolliphor® RH40 showed tubular vesicles with EE% of 92.91 ± 0.98%, PS of 388.75 ± 18.99 nm, PDI of 0.363 ± 0.01, and ZP of 30.36 ± 0.69 mV. Also, it remained stable for 90 days and manifested great mucoadhesive aspects. The optimum CER was incorporated into calcium alginate to prepare nanocomposite hydrogel. The ex-vivo evaluation illustrated that PNL was permeated in a more prolonged pattern from PNL-loaded CERs nanocomposite related to PNL-composite, optimum CER, and PNL solution. Confocal laser scanning microscopy revealed a perfect accumulation of fluorescein-labeled CERs in the skin. The in-silico investigation illustrated that the PNL was stable when mixed with other ingredients in the CERs and confirmed that PNL is a promising candidate for curing MRSA. Moreover, the PNL-loaded CERs nanocomposite revealed superiority over the PNL solution in inhibiting biofilm formation and eradication. The PNL-loaded CERs nanocomposite showed superiority over the PNL-composite for treating MRSA infection in the in-vivo mice model. Histopathological studies revealed the safety of the tested formulations. In conclusion, PNL-loaded CERs nanocomposite provided a promising, safe cure for MRSA bacterial skin infection.
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Affiliation(s)
- Moaz A Eltabeeb
- Department of Industrial Pharmacy, College of Pharmaceutical Sciences and Drug Manufacturing, Misr University for Science and Technology, Giza, Egypt.
| | - Raghda Rabe Hamed
- Department of Industrial Pharmacy, College of Pharmaceutical Sciences and Drug Manufacturing, Misr University for Science and Technology, Giza, Egypt
| | - Mohamed A El-Nabarawi
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Mahmoud H Teaima
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Mohammed I A Hamed
- Organic and Medicinal Chemistry Department, Faculty of Pharmacy, Fayoum University, Faiyum, Egypt
| | - Khaled M Darwish
- Department of Medicinal Chemistry, Faculty of Pharmacy, Suez Canal University, Ismailia, 41522, Egypt
| | - Mariam Hassan
- Department of Microbiology and Immunology, Faculty of Pharmacy, Galala University, New Galala City, Suez, 43511, Egypt
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt
| | - Menna M Abdellatif
- Department of Industrial Pharmacy, College of Pharmaceutical Sciences and Drug Manufacturing, Misr University for Science and Technology, Giza, Egypt
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Budama-Kilinc Y, Gok B, Cetin Aluc C, Kecel-Gunduz S. In vitro and in silico evaluation of the design of nano-phyto-drug candidate for oral use against Staphylococcus aureus. PeerJ 2023; 11:e15523. [PMID: 37309371 PMCID: PMC10257901 DOI: 10.7717/peerj.15523] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 05/17/2023] [Indexed: 06/14/2023] Open
Abstract
Onopordum acanthium is a medicinal plant with many important properties, such as antibacterial, anticancer, and anti-hypotensive properties. Although various studies reported the biological activities of O. acanthium, there is no study on its nano-phyto-drug formulation. The aim of this study is to develop a candidate nano-drug based on phytotherapeutic constituents and evaluate its efficiency in vitro and in silico. In this context, poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) of O. acanthium extract (OAE) were synthesized and characterized. It was determined that the average particle size of OAE-PLGA-NPs was 214.9 ± 6.77 nm, and the zeta potential was -8.03 ± 0.85 mV, and PdI value was 0.064 ± 0.013. The encapsulation efficiency of OAE-PLGA-NPs was calculated as 91%, and the loading capacity as 75.83%. The in vitro drug release study showed that OAE was released from the PLGA NPs with 99.39% over the 6 days. Furthermore, the mutagenic and cytotoxic activity of free OAE and OAE-PLGA-NPs were evaluated by the Ames test and MTT test, respectively. Although 0.75 and 0.37 mg/mL free OAE concentrations caused both frameshift mutation and base pair substitution (p < 0.05), the administered OAE-PLGA NP concentrations were not mutagenic. It was determined with the MTT analysis that the doses of 0.75 and 1.5 mg/mL of free OAE had a cytotoxic effect on the L929 fibroblast cell line (p < 0.05), and OAE-PLGA-NPs had no cytotoxic effect. Moreover, the interaction between the OAE and S. aureus was also investigated using the molecular docking analysis method. The molecular docking and molecular dynamics (MD) results were implemented to elucidate the S. aureus MurE inhibition potential of OAE. It was shown that quercetin in the OAE content interacted significantly with the substantial residues in the catalytic pocket of the S. aureus MurE enzyme, and quercetin performed four hydrogen bond interactions corresponding to a low binding energy of -6.77 kcal/mol with catalytic pocket binding residues, which are crucial for the inhibition mechanism of S. aureus MurE. Finally, the bacterial inhibition values of free OAE and OAE-PLGA NPs were determined against S. aureus using a microdilution method. The antibacterial results showed that the inhibition value of the OAE-PLGA NPs was 69%. In conclusion, from the in vitro and in silico results of the nano-sized OAE-PLGA NP formulation produced in this study, it was evaluated that the formulation may be recommended as a safe and effective nano-phyto-drug candidate against S. aureus.
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Affiliation(s)
- Yasemin Budama-Kilinc
- Bioengineering Department, Yildiz Technical University, Istanbul, Turkey
- Health Biotechnology Joint Research and Application Center of Excellence, Istanbul, Turkey
| | - Bahar Gok
- Graduate School of Natural and Applied Science, Yildiz Technical University, Istanbul, Turkey
| | - Cigdem Cetin Aluc
- Graduate School of Natural and Applied Science, Yildiz Technical University, Istanbul, Turkey
- Abdi Ibrahim Production Facilities, Abdi Ibrahim Pharmaceuticals, Istanbul, Turkey
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Shirakawa KT, Sala FA, Miyachiro MM, Job V, Trindade DM, Dessen A. Architecture and genomic arrangement of the MurE-MurF bacterial cell wall biosynthesis complex. Proc Natl Acad Sci U S A 2023; 120:e2219540120. [PMID: 37186837 PMCID: PMC10214165 DOI: 10.1073/pnas.2219540120] [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: 11/15/2022] [Accepted: 04/05/2023] [Indexed: 05/17/2023] Open
Abstract
Peptidoglycan (PG) is a central component of the bacterial cell wall, and the disruption of its biosynthetic pathway has been a successful antibacterial strategy for decades. PG biosynthesis is initiated in the cytoplasm through sequential reactions catalyzed by Mur enzymes that have been suggested to associate into a multimembered complex. This idea is supported by the observation that in many eubacteria, mur genes are present in a single operon within the well conserved dcw cluster, and in some cases, pairs of mur genes are fused to encode a single, chimeric polypeptide. We performed a vast genomic analysis using >140 bacterial genomes and mapped Mur chimeras in numerous phyla, with Proteobacteria carrying the highest number. MurE-MurF, the most prevalent chimera, exists in forms that are either directly associated or separated by a linker. The crystal structure of the MurE-MurF chimera from Bordetella pertussis reveals a head-to-tail, elongated architecture supported by an interconnecting hydrophobic patch that stabilizes the positions of the two proteins. Fluorescence polarization assays reveal that MurE-MurF interacts with other Mur ligases via its central domains with KDs in the high nanomolar range, backing the existence of a Mur complex in the cytoplasm. These data support the idea of stronger evolutionary constraints on gene order when encoded proteins are intended for association, establish a link between Mur ligase interaction, complex assembly and genome evolution, and shed light on regulatory mechanisms of protein expression and stability in pathways of critical importance for bacterial survival.
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Affiliation(s)
- Karina T. Shirakawa
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, São Paulo13084-971, Brazil
- Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas, CEP Campinas, São Paulo13083-862, Brazil
| | - Fernanda Angélica Sala
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, São Paulo13084-971, Brazil
| | - Mayara M. Miyachiro
- Univ. Grenoble Alpes, CNRS, Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, Bacterial Pathogenesis Group, GrenobleF-38044, France
| | - Viviana Job
- Univ. Grenoble Alpes, CNRS, Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, Bacterial Pathogenesis Group, GrenobleF-38044, France
| | - Daniel Maragno Trindade
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, São Paulo13084-971, Brazil
| | - Andréa Dessen
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, São Paulo13084-971, Brazil
- Univ. Grenoble Alpes, CNRS, Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, Bacterial Pathogenesis Group, GrenobleF-38044, France
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Kim W, Kim M, Park W. Unlocking the mystery of lysine toxicity on Microcystis aeruginosa. JOURNAL OF HAZARDOUS MATERIALS 2023; 448:130932. [PMID: 36860069 DOI: 10.1016/j.jhazmat.2023.130932] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 01/19/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Lysine toxicity on certain groups of bacterial cells has been recognized for many years, but the detailed molecular mechanisms that drive this phenomenon have not been elucidated. Many cyanobacteria including Microcystis aeruginosa cannot efficiently export and degrade lysine, although they have evolved to maintain a single copy of the lysine uptake system through which arginine or ornithine can also be transported into the cytoplasm. Autoradiographic analysis using 14C-l-lysine confirmed that lysine was competitively uptaken into cells with arginine or ornithine, which explained the arginine or ornithine-mediated alleviation of lysine toxicity in M. aeruginosa. A relatively non-specific MurE amino acid ligase could incorporate l-lysine into the 3rd position of UDP-N-acetylmuramyl-tripeptide by replacing meso-diaminopimelic acid during the stepwise addition of amino acids on peptidoglycan (PG) biosynthesis. However, further transpeptidation was blocked because lysine substitution at the pentapeptide of the cell wall inhibited the activity of transpeptidases. The leaky PG structure caused irreversible damage to the photosynthetic system and membrane integrity. Collectively, our results suggest that a lysine-mediated coarse-grained PG network and the absence of concrete septal PG lead to the death of slow-growing cyanobacteria.
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Affiliation(s)
- Wonjae Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Minkyung Kim
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Woojun Park
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
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de Oliveira Rossini N, Dos Santos Silva C, Vinicius Bertacine Dias M. The crystal structure of Mycobacterium thermoresistibile MurE ligase reveals the binding mode of the substrate m-diaminopimelate. J Struct Biol 2023; 215:107957. [PMID: 36944394 DOI: 10.1016/j.jsb.2023.107957] [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: 11/02/2022] [Revised: 03/14/2023] [Accepted: 03/15/2023] [Indexed: 03/23/2023]
Abstract
The cytoplasmatic biosynthesis of the stem peptide from the peptidoglycan in bacteria involves six steps, which have the role of three ATP-dependent Mur ligases that incorporate three consecutive amino acids to a substrate precursor. MurE is the last Mur ligase to incorporate a free amino acid. Although the structure of MurE from Mycobacterium tuberculosis (MtbMurE) was determined at 3.0Å, the binding mode of (meso-Diaminopimelate) m-DAP and the effect of substrate absence is unknown. Herein, we show the structure of MurE from M. thermoresistibile (MthMurE) in complex with ADP and m-DAP at 1.4 Å resolution. The analysis of the structure indicates key conformational changes that the substrate UDP-MurNAc-L-Ala-D-Glu (UAG) and the free amino acid m-DAP cause on the MthMurE conformation. We observed several movements of domains or loop regions that displace their position in order to perform enzymatic catalysis. Since MthMurE has a high similarity to MtbMurE, this enzyme could also guide strategies for structure-based antimicrobial discovery to fight against tuberculosis or other mycobacterial infections. Synopsis Structural characterization of Mycobacterium thermoresistibile MurE at 1.45Å resolution in complex with ADP and m-DAP shows novel conformational changes when compared to other MurE structures in complex with different ligands.
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Affiliation(s)
- Nicolas de Oliveira Rossini
- Department of Microbiology, Institute of Biomedical Science, University of São Paulo. Av. Prof Lineu Prestes, 1374, CEP 05508-000, São Paulo, SP. Brazil
| | - Catharina Dos Santos Silva
- Department of Microbiology, Institute of Biomedical Science, University of São Paulo. Av. Prof Lineu Prestes, 1374, CEP 05508-000, São Paulo, SP. Brazil
| | - Marcio Vinicius Bertacine Dias
- Department of Microbiology, Institute of Biomedical Science, University of São Paulo. Av. Prof Lineu Prestes, 1374, CEP 05508-000, São Paulo, SP. Brazil; Department of Chemistry. The University of Warwick, Coventry, CV4 7AL, UK.
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Subedi BP, Schofield LR, Carbone V, Wolf M, Martin WF, Ronimus RS, Sutherland-Smith AJ. Structural characterisation of methanogen pseudomurein cell wall peptide ligases homologous to bacterial MurE/F murein peptide ligases. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36178458 DOI: 10.1099/mic.0.001235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Archaea have diverse cell wall types, yet none are identical to bacterial peptidoglycan (murein). Methanogens Methanobacteria and Methanopyrus possess cell walls of pseudomurein, a structural analogue of murein. Pseudomurein differs from murein in containing the unique archaeal sugar N-acetyltalosaminuronic acid instead of N-acetylmuramic acid, β-1,3 glycosidic bonds in place of β-1,4 bonds and only l-amino acids in the peptide cross-links. We have determined crystal structures of methanogen pseudomurein peptide ligases (termed pMurE) from Methanothermus fervidus (Mfer762) and Methanothermobacter thermautotrophicus (Mth734) that are structurally most closely related to bacterial MurE peptide ligases. The homology of the archaeal pMurE and bacterial MurE enzymes is clear both in the overall structure and at the level of each of the three domains. In addition, we identified two UDP-binding sites in Mfer762 pMurE, one at the exterior surface of the interface of the N-terminal and middle domains, and a second site at an inner surface continuous with the highly conserved interface of the three domains. Residues involved in ATP binding in MurE are conserved in pMurE, suggesting that a similar ATP-binding pocket is present at the interface of the middle and the C-terminal domains of pMurE. The presence of pMurE ligases in members of the Methanobacteriales and Methanopyrales, that are structurally related to bacterial MurE ligases, supports the idea that the biosynthetic origins of archaeal pseudomurein and bacterial peptidoglycan cell walls are evolutionarily related.
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Affiliation(s)
- Bishwa P Subedi
- AgResearch Ltd, Grasslands, Tennent Drive, Palmerston North, 4442, New Zealand.,School of Natural Sciences, Massey University, Palmerston North 4442, New Zealand.,Present address: Faculty of Medicine, Nursing and Health Sciences, Monash Biomedicine Discovery Institute, Monash University, Victoria 3800, Australia
| | - Linley R Schofield
- AgResearch Ltd, Grasslands, Tennent Drive, Palmerston North, 4442, New Zealand
| | - Vincenzo Carbone
- AgResearch Ltd, Grasslands, Tennent Drive, Palmerston North, 4442, New Zealand
| | - Maximilian Wolf
- AgResearch Ltd, Grasslands, Tennent Drive, Palmerston North, 4442, New Zealand.,Present address: Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, Centre for Water and Environmental Research, University of Duisburg-Essen, 45141 Essen, Germany
| | - William F Martin
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Ron S Ronimus
- AgResearch Ltd, Grasslands, Tennent Drive, Palmerston North, 4442, New Zealand
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Dowson AJ, Lloyd AJ, Cuming AC, Roper DI, Frigerio L, Dowson CG. Plant peptidoglycan precursor biosynthesis: Conservation between moss chloroplasts and Gram-negative bacteria. PLANT PHYSIOLOGY 2022; 190:165-179. [PMID: 35471580 PMCID: PMC9434261 DOI: 10.1093/plphys/kiac176] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 03/06/2022] [Indexed: 06/14/2023]
Abstract
Accumulating evidence suggests that peptidoglycan, consistent with a bacterial cell wall, is synthesized around the chloroplasts of many photosynthetic eukaryotes, from glaucophyte algae to early-diverging land plants including pteridophyte ferns, but the biosynthetic pathway has not been demonstrated. Here, we employed mass spectrometry and enzymology in a two-fold approach to characterize the synthesis of peptidoglycan in chloroplasts of the moss Physcomitrium (Physcomitrella) patens. To drive the accumulation of peptidoglycan pathway intermediates, P. patens was cultured with the antibiotics fosfomycin, D-cycloserine, and carbenicillin, which inhibit key peptidoglycan pathway proteins in bacteria. Mass spectrometry of the trichloroacetic acid-extracted moss metabolome revealed elevated levels of five of the predicted intermediates from uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) through the uridine diphosphate N-acetylmuramic acid (UDP-MurNAc)-D,L-diaminopimelate (DAP)-pentapeptide. Most Gram-negative bacteria, including cyanobacteria, incorporate meso-diaminopimelic acid (D,L-DAP) into the third residue of the stem peptide of peptidoglycan, as opposed to L-lysine, typical of most Gram-positive bacteria. To establish the specificity of D,L-DAP incorporation into the P. patens precursors, we analyzed the recombinant protein UDP-N-acetylmuramoyl-L-alanyl-D-glutamate-2,6-diaminopimelate ligase (MurE) from both P. patens and the cyanobacterium Anabaena sp. (Nostoc sp. strain PCC 7120). Both ligases incorporated D,L-DAP in almost complete preference to L-Lys, consistent with the mass spectrophotometric data, with catalytic efficiencies similar to previously documented Gram-negative bacterial MurE ligases. We discuss how these data accord with the conservation of active site residues common to DL-DAP-incorporating bacterial MurE ligases and of the probability of a horizontal gene transfer event within the plant peptidoglycan pathway.
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Affiliation(s)
- Amanda J Dowson
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Adrian J Lloyd
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Andrew C Cuming
- Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - David I Roper
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Lorenzo Frigerio
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
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Saqallah FG, Hamed WM, Talib WH, Dianita R, Wahab HA. Antimicrobial activity and molecular docking screening of bioactive components of Antirrhinum majus (snapdragon) aerial parts. Heliyon 2022; 8:e10391. [PMID: 36072262 PMCID: PMC9441312 DOI: 10.1016/j.heliyon.2022.e10391] [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: 12/29/2021] [Revised: 05/19/2022] [Accepted: 08/15/2022] [Indexed: 11/28/2022] Open
Abstract
Background Antirrhinum majus (Snapdragon) is a perennial Mediterranean-native plant that is commonly used for mass display. Few reports acknowledged the traditional use of A. majus for its medicinal and therapeutic effects. Herein, we assess the impact of A. majus’s sample preparation and extraction methods on the plant-aerial parts’ phytochemical contents and antimicrobial activity. Furthermore, the microbial targets of the extracts’ secondary metabolites are inspected using molecular docking simulations. Methods The leaves and flowers of A. majus were prepared as fresh and air-dried samples, then extracted using cold maceration and hot reflux, respectively. Extracts with the best phytochemical profiles were selected to test their antimicrobial activities against Bacillus subtilis, Staphylococcus aureus, Enterobacter aerogenes, Escherichia coli and Candida albicans. Besides, molecular docking of 66 reported isolated compounds was conducted against various microbial targets. Results The dried-refluxed samples revealed a massive deterioration in their phytochemical profiles, whereas the macerated flowers extract exhibited the highest total phenolic content and antimicrobial activity against all tested bacterial strains. However, both flowers and leaves extracts showed similar minimum inhibitory and lethal concentrations against C. albicans. Molecular docking studies revealed that chlorogenic acid, chalcononaringenin 4’-glucoside, 3,4,2’,4’,6’-pentahydroxy-chalcone 4’-glucoside, apigenin-7-glucuronide, and luteolin-7-glucuronide were the lead compounds in expressing the antimicrobial activity. Yet, A. majus’s compounds could neither inhibit the 30S ribosomal subunit nor muramyl ligase E. Conclusion Our results suggest that cold maceration of A. majus fresh aerial parts gave higher flavonoid and phenolic content contributing to its antimicrobial properties. These flavonoids and phenolic compounds are predicted to have a crucial role in inhibiting fungal sterol 14-demethylase, and bacterial dihydropteroate synthase and gyrase B subunit proteins. Air-drying of A. majus’s aerial parts deteriorates its phytochemical composition, affecting its antimicrobial activity. A. majus’s fresh-flowers macerate exhibited the highest total phenolic content and antibacterial activity. The antimycotic activity of A. majus was the same for flowers and leaves macerates. In-silico results showed that some phenolics, chalcones, and flavonoids are responsible for the antimicrobial activity. A.majus’s components act on fungal sterol 14-demethylase, and bacterial dihydropteroate synthase and gyrase B enzymes.
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Affiliation(s)
- Fadi G. Saqallah
- Discipline of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
- Faculty of Pharmacy, Applied Science Private University, 11931, Amman, Jordan
| | - Wafaa M. Hamed
- Pharmacy Department, Al-Noor University College, 41019, Mosul, Iraq
- Corresponding author.
| | - Wamidh H. Talib
- Faculty of Pharmacy, Applied Science Private University, 11931, Amman, Jordan
| | - Roza Dianita
- Discipline of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
| | - Habibah A. Wahab
- Discipline of Pharmaceutical Technology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
- Corresponding author.
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In Silico Molecular Analysis and Docking of Potent Antimicrobial Peptides Against MurE Enzyme of Methicillin Resistant Staphylococcus Aureus. Int J Pept Res Ther 2021. [DOI: 10.1007/s10989-021-10165-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Jung KH, Kim YG, Kim CM, Ha HJ, Lee CS, Lee JH, Park HH. Wide-open conformation of UDP-MurNc-tripeptide ligase revealed by the substrate-free structure of MurE from Acinetobacter baumannii. FEBS Lett 2020; 595:275-283. [PMID: 33230844 DOI: 10.1002/1873-3468.14007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/22/2020] [Accepted: 11/20/2020] [Indexed: 12/13/2022]
Abstract
MurE ligase catalyzes the attachment of meso-diaminopimelic acid to the UDP-MurNAc-l -Ala-d -Glu using ATP and producing UDP-MurNAc-l -Ala-d -Glu-meso-A2 pm during bacterial cell wall biosynthesis. Owing to the critical role of this enzyme, MurE is considered an attractive target for antibacterial drugs. Despite extensive studies on MurE ligase, the structural dynamics of its conformational changes are still elusive. In this study, we present the substrate-free structure of MurE from Acinetobacter baumannii, which is an antibiotic-resistant superbacterium that has threatened global public health. The structure revealed that MurE has a wide-open conformation and undergoes wide-open, intermediately closed, and fully closed dynamic conformational transition. Unveiling structural dynamics of MurE will help to understand the working mechanism of this ligase and to design next-generation antibiotics targeting MurE.
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Affiliation(s)
- Kyoung Ho Jung
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, Seoul, Korea.,College of Pharmacy, Chung-Ang University, Seoul, Korea
| | - Yeon-Gil Kim
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, Korea
| | - Chang Min Kim
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, Seoul, Korea.,College of Pharmacy, Chung-Ang University, Seoul, Korea
| | - Hyun Ji Ha
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, Seoul, Korea.,College of Pharmacy, Chung-Ang University, Seoul, Korea
| | - Chang Sup Lee
- College of Pharmacy and Research Institute of Pharmaceutical Science, Gyeongsang National University, Jinju, Korea
| | - Jun Hyuck Lee
- Unit of Research for Practical Application, Korea Polar Research Institute, Incheon, Korea.,Department of Polar Sciences, University of Science and Technology, Incheon, Korea
| | - Hyun Ho Park
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, Seoul, Korea.,College of Pharmacy, Chung-Ang University, Seoul, Korea
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12
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Assembly of Peptidoglycan Fragments-A Synthetic Challenge. Pharmaceuticals (Basel) 2020; 13:ph13110392. [PMID: 33203094 PMCID: PMC7696421 DOI: 10.3390/ph13110392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/09/2020] [Accepted: 11/12/2020] [Indexed: 11/19/2022] Open
Abstract
Peptidoglycan (PGN) is a major constituent of most bacterial cell walls that is recognized as a primary target of the innate immune system. The availability of pure PGN molecules has become key to different biological studies. This review aims to (1) provide an overview of PGN biosynthesis, focusing on the main biosynthetic intermediates; (2) focus on the challenges for chemical synthesis posed by the unique and complex structure of PGN; and (3) cover the synthetic routes of PGN fragments developed to date. The key difficulties in the synthesis of PGN molecules mainly involve stereoselective glycosylation involving NAG derivatives. The complex synthesis of the carbohydrate backbone commonly involves multistep sequences of chemical reactions to install the lactyl moiety at the O-3 position of NAG derivatives and to control enantioselective glycosylation. Recent advances are presented and synthetic routes are described according to the main strategy used: (i) based on the availability of starting materials such as glucosamine derivatives; (ii) based on a particular orthogonal synthesis; and (iii) based on the use of other natural biopolymers as raw materials.
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13
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MurE inhibitors as antibacterial agents: a review. J INCL PHENOM MACRO 2020. [DOI: 10.1007/s10847-020-01018-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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14
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Structural and conformational behavior of MurE ligase from Salmonella enterica serovar Typhi at different temperature and pH conditions. Int J Biol Macromol 2020; 150:389-399. [DOI: 10.1016/j.ijbiomac.2020.01.306] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 11/20/2022]
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15
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Catherwood AC, Lloyd AJ, Tod JA, Chauhan S, Slade SE, Walkowiak GP, Galley NF, Punekar AS, Smart K, Rea D, Evans ND, Chappell MJ, Roper DI, Dowson CG. Substrate and Stereochemical Control of Peptidoglycan Cross-Linking by Transpeptidation by Escherichia coli PBP1B. J Am Chem Soc 2020; 142:5034-5048. [DOI: 10.1021/jacs.9b08822] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Role of MurT C-Terminal Domain in the Amidation of Staphylococcus aureus Peptidoglycan. Antimicrob Agents Chemother 2019; 63:AAC.00957-19. [PMID: 31358586 DOI: 10.1128/aac.00957-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/20/2019] [Indexed: 11/20/2022] Open
Abstract
Glutamate amidation, a secondary modification of the peptidoglycan, was first identified in Staphylococcus aureus It is catalyzed by the protein products of the murT and gatD genes, which are conserved and colocalized in the genomes of most sequenced Gram-positive bacterial species. The MurT-GatD complex is required for cell viability, full resistance to β-lactam antibiotics, and resistance to human lysozyme and is recognized as an attractive target for new antimicrobials. Great effort has been invested in the study of this step, culminating recently in three independent reports addressing the structural elucidation of the MurT-GatD complex. In this work, we demonstrate through the use of nonstructural approaches the critical and multiple roles of the C-terminal domain of MurT, annotated as DUF1727, in the MurT-GatD enzymatic complex. This domain provides the physical link between the two enzymatic activities and is essential for the amidation reaction. Copurification of recombinant MurT and GatD proteins and bacterial two-hybrid assays support the observation that the MurT-GatD interaction occurs through this domain. Most importantly, we provide in vivo evidence of the effect of substitutions at specific residues in DUF1727 on cell wall peptidoglycan amidation and on the phenotypes of oxacillin resistance and bacterial growth.
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17
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Nöldeke ER, Stehle T. Unraveling the mechanism of peptidoglycan amidation by the bifunctional enzyme complex GatD/MurT: A comparative structural approach. Int J Med Microbiol 2019; 309:151334. [PMID: 31383542 DOI: 10.1016/j.ijmm.2019.151334] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 07/11/2019] [Accepted: 07/17/2019] [Indexed: 10/26/2022] Open
Abstract
The bacterial cell wall provides structural integrity to the cell and protects the cell from internal pressure and the external environment. During the course of the twelve-year funding period of the Collaborative Research Center 766, our work has focused on conducting structure-function studies of enzymes that modify (synthesize or cleave) cell wall components of a range of bacteria including Staphylococcus aureus, Staphylococcus epidermidis, and Nostoc punctiforme. Several of our structures represent promising targets for interference. In this review, we highlight a recent structure-function analysis of an enzyme complex that is responsible for the amidation of Lipid II, a peptidoglycan precursor, in S. aureus.
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Affiliation(s)
- Erik R Nöldeke
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076 Tübingen, Germany
| | - Thilo Stehle
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076 Tübingen, Germany; Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA.
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18
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Possible role of rivoglitazone thiazolidine class of drug as dual-target therapeutic agent for bacterial infections: An in silico study. Med Hypotheses 2019; 131:109305. [PMID: 31443754 DOI: 10.1016/j.mehy.2019.109305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/18/2019] [Accepted: 07/05/2019] [Indexed: 01/12/2023]
Abstract
Infections due to resistant bacteria are the life-threatening and leading cause of mortality worldwide. The current therapy for bacterial infections includes treatment with various drugs and antibiotics. The misuse and over usage of these antibiotics leads to bacterial resistance. There are several mechanisms by which bacteria exhibit resistance to some antibiotics. These include drug inactivation or modification, elimination of antibiotics through efflux pumps, drug target alteration, and modification of metabolic pathway. However, it is difficult to treat infections caused by resistant bacteria by conventional existing therapy. In the present study binding affinities of some glitazones against ParE and MurE bacterial enzymes are investigated by in silico methods. As evident by extra-precision docking and binding free energy calculation (MM-GBSA) results, rivoglitazone exhibited higher binding affinity against both ParE and MurE enzymes compared to all other selected compounds. Further molecular dynamic (MD) simulations were performed to validate the stability of rivoglitazone/4MOT and rivoglitazone/4C13 complexes and to get insight into the binding mode of inhibitor. Thus, we hypothesize that structural modifications of the rivoglitazone scaffold can be useful for the development of an effective antibacterial agent.
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19
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Azam MA, Saha N, Jupudi S. An explorative study on Staphylococcus aureus MurE inhibitor: induced fit docking, binding free energy calculation, and molecular dynamics. J Recept Signal Transduct Res 2019; 39:45-54. [PMID: 31162992 DOI: 10.1080/10799893.2019.1605528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Staphylococcus aureus MurE enzyme catalyzes the addition of l-lysine as third residue of the peptidoglycan peptide moiety. Due to the high substrate specificity and its ubiquitous nature among bacteria, MurE enzyme is considered as one of the potential target for the development of new therapeutic agents. In the present work, induced fit docking (IFD), binding free energy calculation, and molecular dynamics (MD) simulation were carried out to elucidate the inhibition potential of 2-thioxothiazolidin-4-one based inhibitor 1 against S. aureus MurE enzyme. The inhibitor 1 formed majority of hydrogen bonds with the central domain residues Asn151, Thr152, Ser180, Arg187, and Lys219. Binding free-energy calculation by MM-GBSA approach showed that van der Waals (ΔGvdW, -57.30 kcal/mol) and electrostatic solvation (ΔGsolv, -36.86 kcal/mol) energy terms are major contributors for the inhibitor binding. Further, 30-ns MD simulation was performed to validate the stability of ligand-protein complex and also to get structural insight into mode of binding. Based on the IFD and MD simulation results, we designed four new compounds D1-D4 with promising binding affinity for the S. aureus MurE enzyme. The designed compounds were subjected to the extra-precision docking and binding free energy was calculated for complexes. Further, a 30-ns MD simulation was performed for D1/4C13 complex.
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Affiliation(s)
- Mohammed Afzal Azam
- a Department of Pharmaceutical Chemistry, JSS College of Pharmacy , Ooty , Tamil Nadu , India
| | - Niladri Saha
- a Department of Pharmaceutical Chemistry, JSS College of Pharmacy , Ooty , Tamil Nadu , India
| | - Srikanth Jupudi
- a Department of Pharmaceutical Chemistry, JSS College of Pharmacy , Ooty , Tamil Nadu , India
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20
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Structure based in-silico study on UDP-N-acetylmuramoyl-L-alanyl-D-glutamate-2,6-diaminopimelate ligase (MurE) from Acinetobacter baumannii as a drug target against nosocomial infections. INFORMATICS IN MEDICINE UNLOCKED 2019. [DOI: 10.1016/j.imu.2019.100216] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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21
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Nöldeke ER, Muckenfuss LM, Niemann V, Müller A, Störk E, Zocher G, Schneider T, Stehle T. Structural basis of cell wall peptidoglycan amidation by the GatD/MurT complex of Staphylococcus aureus. Sci Rep 2018; 8:12953. [PMID: 30154570 PMCID: PMC6113224 DOI: 10.1038/s41598-018-31098-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 08/06/2018] [Indexed: 01/09/2023] Open
Abstract
The peptidoglycan of Staphylococcus aureus is highly amidated. Amidation of α-D-isoglutamic acid in position 2 of the stem peptide plays a decisive role in the polymerization of cell wall building blocks. S. aureus mutants with a reduced degree of amidation are less viable and show increased susceptibility to methicillin, indicating that targeting the amidation reaction could be a useful strategy to combat this pathogen. The enzyme complex that catalyzes the formation of α-D-isoglutamine in the Lipid II stem peptide was identified recently and shown to consist of two subunits, the glutamine amidotransferase-like protein GatD and the Mur ligase homolog MurT. We have solved the crystal structure of the GatD/MurT complex at high resolution, revealing an open, boomerang-shaped conformation in which GatD is docked onto one end of MurT. Putative active site residues cluster at the interface between GatD and MurT and are contributed by both proteins, thus explaining the requirement for the assembled complex to carry out the reaction. Site-directed mutagenesis experiments confirm the validity of the observed interactions. Small-angle X-ray scattering data show that the complex has a similar conformation in solution, although some movement at domain interfaces can occur, allowing the two proteins to approach each other during catalysis. Several other Gram-positive pathogens, including Streptococcus pneumoniae, Clostridium perfringens and Mycobacterium tuberculosis have homologous enzyme complexes. Combined with established biochemical assays, the structure of the GatD/MurT complex provides a solid basis for inhibitor screening in S. aureus and other pathogens.
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Affiliation(s)
- Erik R Nöldeke
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076, Tübingen, Germany
| | - Lena M Muckenfuss
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076, Tübingen, Germany.,Department of Biochemistry, University of Zurich, CH-8057, Zurich, Switzerland
| | - Volker Niemann
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076, Tübingen, Germany.,Hain Lifescience GmbH, D-72147, Nehren, Germany
| | - Anna Müller
- Institute for Pharmaceutical Microbiology, University of Bonn, D-53115, Bonn, Germany
| | - Elena Störk
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076, Tübingen, Germany
| | - Georg Zocher
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076, Tübingen, Germany
| | - Tanja Schneider
- Institute for Pharmaceutical Microbiology, University of Bonn, D-53115, Bonn, Germany
| | - Thilo Stehle
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076, Tübingen, Germany. .,Vanderbilt University School of Medicine, Nashville, Tennessee, 37232, USA.
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22
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Zhao H, Roistacher DM, Helmann JD. Aspartate deficiency limits peptidoglycan synthesis and sensitizes cells to antibiotics targeting cell wall synthesis in Bacillus subtilis. Mol Microbiol 2018; 109:826-844. [PMID: 29995990 DOI: 10.1111/mmi.14078] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 07/02/2018] [Accepted: 07/05/2018] [Indexed: 12/31/2022]
Abstract
Peptidoglycan synthesis is an important target for antibiotics and relies on intermediates derived from central metabolism. As a result, alterations of metabolism may affect antibiotic sensitivity. An aspB mutant is auxotrophic for aspartate (Asp) and asparagine (Asn) and lyses when grown in Difco sporulation medium (DSM), but not in LB medium. Genetic and physiological studies, supported by amino acid analysis, reveal that cell lysis in DSM results from Asp limitation due to a relatively low Asp and high glutamate (Glu) concentrations, with Glu functioning as a competitive inhibitor of Asp uptake by the major Glu/Asp transporter GltT. Lysis can be specifically suppressed by supplementation with 2,6-diaminopimelate (DAP), which is imported by two different cystine uptake systems. These studies suggest that aspartate limitation depletes the peptidoglycan precursor meso-2,6-diaminopimelate (mDAP), inhibits peptidoglycan synthesis, upregulates the cell envelope stress response mediated by σM and eventually leads to cell lysis. Aspartate limitation sensitizes cells to antibiotics targeting late steps of PG synthesis, but not steps prior to the addition of mDAP into the pentapeptide sidechain. This work highlights the ability of perturbations of central metabolism to sensitize cells to peptidoglycan synthesis inhibitors.
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Affiliation(s)
- Heng Zhao
- Department of Microbiology, Cornell University, Ithaca, NY, USA
| | | | - John D Helmann
- Department of Microbiology, Cornell University, Ithaca, NY, USA
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23
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Morlot C, Straume D, Peters K, Hegnar OA, Simon N, Villard AM, Contreras-Martel C, Leisico F, Breukink E, Gravier-Pelletier C, Le Corre L, Vollmer W, Pietrancosta N, Håvarstein LS, Zapun A. Structure of the essential peptidoglycan amidotransferase MurT/GatD complex from Streptococcus pneumoniae. Nat Commun 2018; 9:3180. [PMID: 30093673 PMCID: PMC6085368 DOI: 10.1038/s41467-018-05602-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 07/17/2018] [Indexed: 11/08/2022] Open
Abstract
The universality of peptidoglycan in bacteria underlies the broad spectrum of many successful antibiotics. However, in our times of widespread resistance, the diversity of peptidoglycan modifications offers a variety of new antibacterials targets. In some Gram-positive species such as Streptococcus pneumoniae, Staphylococcus aureus, or Mycobacterium tuberculosis, the second residue of the peptidoglycan precursor, D-glutamate, is amidated into iso-D-glutamine by the essential amidotransferase MurT/GatD complex. Here, we present the structure of this complex at 3.0 Å resolution. MurT has central and C-terminal domains similar to Mur ligases with a cysteine-rich insertion, which probably binds zinc, contributing to the interface with GatD. The mechanism of amidation by MurT is likely similar to the condensation catalyzed by Mur ligases. GatD is a glutaminase providing ammonia that is likely channeled to the MurT active site through a cavity network. The structure and assay presented here constitute a knowledge base for future drug development studies.
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Affiliation(s)
- Cécile Morlot
- Université Grenoble Alpes, CNRS, CEA, IBS UMR 5075, 38044, Grenoble, France
| | - Daniel Straume
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, 1432, Norway
| | - Katharina Peters
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Bioscience, Newcastle University, Newcastle Upon Tyne, NE2 4AX, United Kingdom
| | - Olav A Hegnar
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, 1432, Norway
| | - Nolwenn Simon
- Université Grenoble Alpes, CNRS, CEA, IBS UMR 5075, 38044, Grenoble, France
| | - Anne-Marie Villard
- Université Grenoble Alpes, CNRS, CEA, IBS UMR 5075, 38044, Grenoble, France
| | | | - Francisco Leisico
- Departamento de Química, Universidade Nova de Lisboa, Caparica, 2829-516, Portugal
| | - Eefjan Breukink
- Membrane Biochemistry and Biophysics, Department of Chemistry, Faculty of Science, Utrecht University, Utrecht, 3584, The Netherlands
| | - Christine Gravier-Pelletier
- Université Paris Descartes, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques UMR 8601 CNRS, Sorbonne Paris Cité (USPC), Paris, 75006, France
| | - Laurent Le Corre
- Université Paris Descartes, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques UMR 8601 CNRS, Sorbonne Paris Cité (USPC), Paris, 75006, France
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Bioscience, Newcastle University, Newcastle Upon Tyne, NE2 4AX, United Kingdom
| | - Nicolas Pietrancosta
- Université Paris Descartes, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques UMR 8601 CNRS, Sorbonne Paris Cité (USPC), Paris, 75006, France
| | - Leiv Sigve Håvarstein
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, 1432, Norway
| | - André Zapun
- Université Grenoble Alpes, CNRS, CEA, IBS UMR 5075, 38044, Grenoble, France.
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24
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Patin D, Turk S, Barreteau H, Mainardi JL, Arthur M, Gobec S, Mengin-Lecreulx D, Blanot D. Unusual substrate specificity of the peptidoglycan MurE ligase from Erysipelothrix rhusiopathiae. Biochimie 2015; 121:209-18. [PMID: 26700151 DOI: 10.1016/j.biochi.2015.12.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 12/06/2015] [Indexed: 01/23/2023]
Abstract
Erysipelothrix rhusiopathiae is a Gram-positive bacterium pathogenic to many species of birds and mammals, including humans. The main feature of its peptidoglycan is the presence of l-alanine at position 3 of the peptide stem. In the present work, we cloned the murE gene from E. rhusiopathiae and purified the corresponding protein as His6-tagged form. Enzymatic assays showed that E. rhusiopathiae MurE was indeed an l-alanine-adding enzyme. Surprisingly, it was also able, although to a lesser extent, to add meso-diaminopimelic acid, the amino acid found at position 3 in many Gram-negative bacteria, Bacilli and Mycobacteria. Sequence alignment of MurE enzymes from E. rhusiopathiae and Escherichia coli revealed that the DNPR motif that is characteristic of meso-diaminopimelate-adding enzymes was replaced by HDNR. The role of the latter motif in the interaction with l-alanine and meso-diaminopimelic acid was demonstrated by site-directed mutagenesis experiments and the construction of a homology model. The overexpression of the E. rhusiopathiae murE gene in E. coli resulted in the incorporation of l-alanine at position 3 of the peptide part of peptidoglycan.
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Affiliation(s)
- Delphine Patin
- Institut de Biologie Intégrative de la Cellule (I2BC), UMR 9198 CEA/CNRS/Université Paris-Sud, 91405 Orsay, France.
| | - Samo Turk
- Fakulteta za Farmacijo, Univerza v Ljubljani, Aškerčeva 7, 1000 Ljubljana, Slovenia
| | - Hélène Barreteau
- Institut de Biologie Intégrative de la Cellule (I2BC), UMR 9198 CEA/CNRS/Université Paris-Sud, 91405 Orsay, France
| | - Jean-Luc Mainardi
- Laboratoire de Recherche Moléculaire sur les Antibiotiques, Centre de Recherche des Cordeliers, Equipe 12, INSERM U1138, 75006 Paris, France; Université Pierre et Marie Curie - Paris 6, UMR S1138, 15 Rue de l'Ecole de Médecine, 75006 Paris, France; Université Paris-Descartes, Sorbonne Paris Cité, UMR S1138, 75006 Paris, France
| | - Michel Arthur
- Laboratoire de Recherche Moléculaire sur les Antibiotiques, Centre de Recherche des Cordeliers, Equipe 12, INSERM U1138, 75006 Paris, France; Université Pierre et Marie Curie - Paris 6, UMR S1138, 15 Rue de l'Ecole de Médecine, 75006 Paris, France; Université Paris-Descartes, Sorbonne Paris Cité, UMR S1138, 75006 Paris, France
| | - Stanislav Gobec
- Fakulteta za Farmacijo, Univerza v Ljubljani, Aškerčeva 7, 1000 Ljubljana, Slovenia
| | - Dominique Mengin-Lecreulx
- Institut de Biologie Intégrative de la Cellule (I2BC), UMR 9198 CEA/CNRS/Université Paris-Sud, 91405 Orsay, France
| | - Didier Blanot
- Institut de Biologie Intégrative de la Cellule (I2BC), UMR 9198 CEA/CNRS/Université Paris-Sud, 91405 Orsay, France
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25
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Vemula H, Ayon NJ, Gutheil WG. Cytoplasmic peptidoglycan intermediate levels in Staphylococcus aureus. Biochimie 2015; 121:72-8. [PMID: 26612730 DOI: 10.1016/j.biochi.2015.11.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 11/18/2015] [Indexed: 11/27/2022]
Abstract
Intracellular cytoplasmic peptidoglycan (PG) intermediate levels were determined in Staphylococcus aureus during log-phase growth in enriched media. Levels of UDP-linked intermediates were quantitatively determined using ion pairing LC-MS/MS in negative mode, and amine intermediates were quantitatively determined stereospecifically as their Marfey's reagent derivatives in positive mode. Levels of UDP-linked intermediates in S. aureus varied from 1.4 μM for UDP-GlcNAc-Enolpyruvyate to 1200 μM for UDP-MurNAc. Levels of amine intermediates (L-Ala, D-Ala, D-Ala-D-Ala, L-Glu, D-Glu, and L-Lys) varied over a range of from 860 μM for D-Ala-D-Ala to 30-260 mM for the others. Total PG was determined from the D-Glu content of isolated PG, and used to estimate the rate of PG synthesis (in terms of cytoplasmic metabolite flux) as 690 μM/min. The total UDP-linked intermediates pool (2490 μM) is therefore sufficient to sustain growth for 3.6 min. Comparison of UDP-linked metabolite levels with published pathway enzyme characteristics demonstrates that enzymes on the UDP-branch range from >80% saturation for MurA, Z, and C, to <5% saturation for MurB. Metabolite levels were compared with literature values for Escherichia coli, with the major difference in UDP-intermediates being the level of UDP-MurNAc, which was high in S. aureus (1200 μM) and low in E. coli (45 μM).
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Affiliation(s)
- Harika Vemula
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 2464 Charlotte Street, Kansas City, MO 64108, USA
| | - Navid J Ayon
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 2464 Charlotte Street, Kansas City, MO 64108, USA
| | - William G Gutheil
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 2464 Charlotte Street, Kansas City, MO 64108, USA.
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26
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Todorova K, Maurer P, Rieger M, Becker T, Bui NK, Gray J, Vollmer W, Hakenbeck R. Transfer of penicillin resistance from Streptococcus oralis to Streptococcus pneumoniae identifies murE as resistance determinant. Mol Microbiol 2015; 97:866-80. [PMID: 26010014 DOI: 10.1111/mmi.13070] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2015] [Indexed: 01/26/2023]
Abstract
Beta-lactam resistant clinical isolates of Streptococcus pneumoniae contain altered penicillin-binding protein (PBP) genes and occasionally an altered murM, presumably products of interspecies gene transfer. MurM and MurN are responsible for the synthesis of branched lipid II, substrate for the PBP catalyzed transpeptidation reaction. Here we used the high-level beta-lactam resistant S. oralis Uo5 as donor in transformation experiments with the sensitive laboratory strain S. pneumoniae R6 as recipient. Surprisingly, piperacillin-resistant transformants contained no alterations in PBP genes but carried murEUo5 encoding the UDP-N-acetylmuramyl tripeptide synthetase. Codons 83-183 of murEUo5 were sufficient to confer the resistance phenotype. Moreover, the promoter of murEUo5 , which drives a twofold higher expression compared to that of S. pneumoniae R6, could also confer increased resistance. Multiple independent transformations produced S. pneumoniae R6 derivatives containing murEUo5 , pbp2xUo5 , pbp1aUo5 and pbp2bUo5 , but not murMUo5 sequences; however, the resistance level of the donor strain could not be reached. S. oralis Uo5 harbors an unusual murM, and murN is absent. Accordingly, the peptidoglycan of S. oralis Uo5 contained interpeptide bridges with one L-Ala residue only. The data suggest that resistance in S. oralis Uo5 is based on a complex interplay of distinct PBPs and other enzymes involved in peptidoglycan biosynthesis.
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Affiliation(s)
- Katya Todorova
- Department of Microbiology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Patrick Maurer
- Department of Microbiology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Martin Rieger
- Department of Microbiology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Tina Becker
- Department of Microbiology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Nhat Khai Bui
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4AX, UK
| | - Joe Gray
- Institute for Cell and Molecular Biosciences, Pinnacle Laboratory, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4AX, UK
| | - Regine Hakenbeck
- Department of Microbiology, University of Kaiserslautern, Kaiserslautern, Germany
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Impact of antibiotics with various target sites on the metabolome of Staphylococcus aureus. Antimicrob Agents Chemother 2014; 58:7151-63. [PMID: 25224006 DOI: 10.1128/aac.03104-14] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
In this study, global intra- and extracellular metabolic profiles were exploited to investigate the impact of antibiotic compounds with different cellular targets on the metabolome of Staphylococcus aureus HG001. Primary metabolism was largely covered, yet uncommon staphylococcal metabolites were detected in the cytosol of S. aureus, including sedoheptulose-1,7-bisphosphate and the UDP-MurNAc-pentapeptide with an alanine-seryl residue. By comparing the metabolic profiles of unstressed and stressed staphylococcal cells in a time-dependent manner, we found far-ranging effects within the metabolome. For each antibiotic compound, accumulation as well as depletion of metabolites was detected, often comprising whole biosynthetic pathways, such as central carbon and amino acid metabolism and peptidoglycan, purine, and pyrimidine synthesis. Ciprofloxacin altered the pool of (deoxy)nucleotides as well as peptidoglycan precursors, thus linking stalled DNA and cell wall synthesis. Erythromycin tended to increase the amounts of intermediates of the pentose phosphate pathway and lysine. Fosfomycin inhibited the first enzymatic step of peptidoglycan synthesis, which was followed by decreased levels of peptidoglycan precursors but enhanced levels of substrates such as UDP-GlcNAc and alanine-alanine. In contrast, vancomycin and ampicillin inhibited the last stage of peptidoglycan construction on the outer cell surface. As a result, the amounts of UDP-MurNAc-peptides drastically increased, resulting in morphological alterations in the septal region and in an overall decrease in central metabolite levels. Moreover, each antibiotic affected intracellular levels of tricarboxylic acid cycle intermediates.
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Kouidmi I, Levesque RC, Paradis-Bleau C. The biology of Mur ligases as an antibacterial target. Mol Microbiol 2014; 94:242-53. [DOI: 10.1111/mmi.12758] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2014] [Indexed: 01/19/2023]
Affiliation(s)
- Imène Kouidmi
- Department of Microbiology, Infectiology and Immunology; Université de Montreal; Montreal Quebec Canada
| | - Roger C. Levesque
- Institut de biologie intégrative et des systèmes; Université Laval; Montreal Quebec Canada
| | - Catherine Paradis-Bleau
- Department of Microbiology, Infectiology and Immunology; Université de Montreal; Montreal Quebec Canada
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