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Keller AP, Huemer M, Chang CC, Mairpady Shambat S, Bjurnemark C, Oberortner N, Santschi MV, Zinsli LV, Röhrig C, Sobieraj AM, Shen Y, Eichenseher F, Zinkernagel AS, Loessner MJ, Schmelcher M. Systemic application of bone-targeting peptidoglycan hydrolases as a novel treatment approach for staphylococcal bone infection. mBio 2023; 14:e0183023. [PMID: 37768041 PMCID: PMC10653945 DOI: 10.1128/mbio.01830-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 08/08/2023] [Indexed: 09/29/2023] Open
Abstract
IMPORTANCE The rising prevalence of antimicrobial resistance in S. aureus has rendered treatment of staphylococcal infections increasingly difficult, making the discovery of alternative treatment options a high priority. Peptidoglycan hydrolases, a diverse group of bacteriolytic enzymes, show high promise as such alternatives due to their rapid and specific lysis of bacterial cells, independent of antibiotic resistance profiles. However, using these enzymes for the systemic treatment of local infections, such as osteomyelitis foci, needs improvement, as the therapeutic distributes throughout the whole host, resulting in low concentrations at the actual infection site. In addition, the occurrence of intracellularly persisting bacteria can lead to relapsing infections. Here, we describe an approach using tissue-targeting to increase the local concentration of therapeutic enzymes in the infected bone. The enzymes were modified with a short targeting moiety that mediated accumulation of the therapeutic in osteoblasts and additionally enables targeting of intracellularly surviving bacteria.
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Affiliation(s)
- Anja P. Keller
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Markus Huemer
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Chun-Chi Chang
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Srikanth Mairpady Shambat
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | | | - Nicole Oberortner
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | | | - Léa V. Zinsli
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Christian Röhrig
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Anna M. Sobieraj
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Yang Shen
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Fritz Eichenseher
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Annelies S. Zinkernagel
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Martin J. Loessner
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Mathias Schmelcher
- Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
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Keller AP, Ly S, Daetwyler S, Eichenseher F, Loessner MJ, Schmelcher M. Chimeric Peptidoglycan Hydrolases Kill Staphylococcal Mastitis Isolates in Raw Milk and within Bovine Mammary Gland Epithelial Cells. Viruses 2022; 14:v14122801. [PMID: 36560804 PMCID: PMC9781970 DOI: 10.3390/v14122801] [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: 11/09/2022] [Revised: 12/03/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Staphylococcus aureus is a major causative agent of bovine mastitis, a disease considered one of the most economically devastating in the dairy sector. Considering the increasing prevalence of antibiotic-resistant strains, novel therapeutic approaches efficiently targeting extra- and intracellular bacteria and featuring high activity in the presence of raw milk components are needed. Here, we have screened a library of eighty peptidoglycan hydrolases (PGHs) for high activity against S. aureus in raw bovine milk, twelve of which were selected for further characterization and comparison in time-kill assays. The bacteriocins lysostaphin and ALE-1, and the chimeric PGH M23LST(L)_SH3b2638 reduced bacterial numbers in raw milk to the detection limit within 10 min. Three CHAP-based PGHs (CHAPGH15_SH3bAle1, CHAPK_SH3bLST_H, CHAPH5_LST_H) showed gradually improving activity with increasing dilution of the raw milk. Furthermore, we demonstrated synergistic activity of CHAPGH15_SH3bAle1 and LST when used in combination. Finally, modification of four PGHs (LST, M23LST(L)_SH3b2638, CHAPK_SH3bLST, CHAPGH15_SH3bAle1) with the cell-penetrating peptide TAT significantly enhanced the eradication of intracellular S. aureus in bovine mammary alveolar cells compared to the unmodified parentals in a concentration-dependent manner.
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Khullar L, Harjai K, Chhibber S. Exploring the therapeutic potential of staphylococcal phage formulations: Current challenges and applications in phage therapy. J Appl Microbiol 2022; 132:3515-3532. [DOI: 10.1111/jam.15462] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 12/21/2021] [Accepted: 01/17/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Lavanya Khullar
- Department of Microbiology Panjab University Chandigarh India
| | - Kusum Harjai
- Department of Microbiology Panjab University Chandigarh India
| | - Sanjay Chhibber
- Department of Microbiology Panjab University Chandigarh India
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Comparative Transcriptome Analysis Reveals Differentially Expressed Genes Related to Antimicrobial Properties of Lysostaphin in Staphylococcus aureus. Antibiotics (Basel) 2022; 11:antibiotics11020125. [PMID: 35203727 PMCID: PMC8868216 DOI: 10.3390/antibiotics11020125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/07/2022] [Accepted: 01/11/2022] [Indexed: 11/17/2022] Open
Abstract
Comparative transcriptome analysis and de novo short-read assembly of S. aureus Newman strains revealed significant transcriptional changes in response to the exposure to triple-acting staphylolytic peptidoglycan hydrolase (PGH) 1801. Most altered transcriptions were associated with the membrane, cell wall, and related genes, including amidase, peptidase, holin, and phospholipase D/transphosphatidylase. The differential expression of genes obtained from RNA-seq was confirmed by reverse transcription quantitative PCR. Moreover, some of these gene expression changes were consistent with the observed structural perturbations at the DNA and RNA levels. These structural changes in the genes encoding membrane/cell surface proteins and altered gene expressions are the candidates for resistance to these novel antimicrobials. The findings in this study could provide insight into the design of new antimicrobial agents.
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Yang Y, Hao K, Jiang M, Memon FU, Guo L, Zhang G, Liu T, Wu X, Si H. Transcriptomic Analysis of Drug-Resistance Acinetobacter baumannii under the Stress Condition Caused by Litsea cubeba L . Essential Oil via RNA Sequencing. Genes (Basel) 2021; 12:1003. [PMID: 34210052 PMCID: PMC8307839 DOI: 10.3390/genes12071003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/03/2021] [Accepted: 06/28/2021] [Indexed: 12/14/2022] Open
Abstract
Litsea cubeba L. essential oil(LCEO) can affect the growth of drug-resistance bacteria. However, research on stress response of drug-resistant A. baumannii under sub-lethal LCEO concentrations had been limited so far. Therefore, transcriptomic analysisof A. baumannii under 1/2 minimum inhibitory concentration (MIC, 0.54 mg/mL) of LCEO was performed. Results of transcriptomic analysis showed that 320/352 genes were significantly up/down-regulated, respectively, in LCEO-treated A. baumannii. Both up and down-regulated genes were significantly enriched in three GO terms (oxidation-reduction process; oxidoreductase activity; oxidoreductase activity, acting on the CH-CH group of donors), which indicated that the redox state of A. baumannii was significantly affected by LCEO. LCEO may also inhibit aerobic respiration, synthesis of ketone bodies and the metabolism of some amino acids while, meanwhile, promoting fatty acid degradation of A. baumannii according to Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. The permeability and the stress of cell membrane of A. baumannii were significantly affected by LCEO. After crystal violet dyeing, the biofilm formation of A. baumannii was promoted/inhibited by extremely low/relatively high concentration of LCEO, respectively. LCEO and chloramphenicol have synergistic growth inhibitory effect against A. baumannii according to the Fractional Inhibitory Concentration Index (FICI) value = 0.375. Our results indicate that the growth of A. baumannii was inhibited by LCEO, and give insights into the stress response of A. baumannii under sub-lethal concentrations of LCEO. These results provided evidence that A. baumannii was inhibited by LCEO, and expanded knowledges of stress response of A. baumannii under sub-lethal concentration of LCEO.
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Affiliation(s)
- Yunqiao Yang
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China; (Y.Y.); (K.H.); (M.J.); (F.U.M.); (G.Z.); (T.L.); (X.W.)
| | - Kaiyuan Hao
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China; (Y.Y.); (K.H.); (M.J.); (F.U.M.); (G.Z.); (T.L.); (X.W.)
| | - Mingsheng Jiang
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China; (Y.Y.); (K.H.); (M.J.); (F.U.M.); (G.Z.); (T.L.); (X.W.)
| | - Fareed Uddin Memon
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China; (Y.Y.); (K.H.); (M.J.); (F.U.M.); (G.Z.); (T.L.); (X.W.)
| | - Lei Guo
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225012, China;
| | - Geyin Zhang
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China; (Y.Y.); (K.H.); (M.J.); (F.U.M.); (G.Z.); (T.L.); (X.W.)
| | - Tian Liu
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China; (Y.Y.); (K.H.); (M.J.); (F.U.M.); (G.Z.); (T.L.); (X.W.)
| | - Xianshi Wu
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China; (Y.Y.); (K.H.); (M.J.); (F.U.M.); (G.Z.); (T.L.); (X.W.)
| | - Hongbin Si
- College of Animal Sciences and Technology, Guangxi University, Nanning 530004, China; (Y.Y.); (K.H.); (M.J.); (F.U.M.); (G.Z.); (T.L.); (X.W.)
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Grabowski Ł, Łepek K, Stasiłojć M, Kosznik-Kwaśnicka K, Zdrojewska K, Maciąg-Dorszyńska M, Węgrzyn G, Węgrzyn A. Bacteriophage-encoded enzymes destroying bacterial cell membranes and walls, and their potential use as antimicrobial agents. Microbiol Res 2021; 248:126746. [PMID: 33773329 DOI: 10.1016/j.micres.2021.126746] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 03/06/2021] [Accepted: 03/08/2021] [Indexed: 01/22/2023]
Abstract
Appearance of pathogenic bacteria resistant to most, if not all, known antibiotics is currently one of the most significant medical problems. Therefore, development of novel antibacterial therapies is crucial for efficient treatment of bacterial infections in the near future. One possible option is to employ enzymes, encoded by bacteriophages, which cause destruction of bacterial cell membranes and walls. Bacteriophages use such enzymes to destroy bacterial host cells at the final stage of their lytic development, in order to ensure effective liberation of progeny virions. Nevertheless, to use such bacteriophage-encoded proteins in medicine and/or biotechnology, it is crucial to understand details of their biological functions and biochemical properties. Therefore, in this review article, we will present and discuss our current knowledge on the processes of bacteriophage-mediated bacterial cell lysis, with special emphasis on enzymes involved in them. Regulation of timing of the lysis is also discussed. Finally, possibilities of the practical use of these enzymes as antibacterial agents will be underlined and perspectives of this aspect will be presented.
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Affiliation(s)
- Łukasz Grabowski
- Laboratory of Phage Therapy, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Kładki 24, 80-822, Gdansk, Poland.
| | - Krzysztof Łepek
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308, Gdansk, Poland.
| | - Małgorzata Stasiłojć
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308, Gdansk, Poland.
| | - Katarzyna Kosznik-Kwaśnicka
- Laboratory of Phage Therapy, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Kładki 24, 80-822, Gdansk, Poland.
| | - Karolina Zdrojewska
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308, Gdansk, Poland.
| | - Monika Maciąg-Dorszyńska
- Laboratory of Phage Therapy, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Kładki 24, 80-822, Gdansk, Poland.
| | - Grzegorz Węgrzyn
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308, Gdansk, Poland.
| | - Alicja Węgrzyn
- Laboratory of Phage Therapy, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Kładki 24, 80-822, Gdansk, Poland.
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7
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Engineering of Long-Circulating Peptidoglycan Hydrolases Enables Efficient Treatment of Systemic Staphylococcus aureus Infection. mBio 2020; 11:mBio.01781-20. [PMID: 32963004 PMCID: PMC7512550 DOI: 10.1128/mbio.01781-20] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Staphylococcus aureus is a human pathogen causing life-threatening diseases. The increasing prevalence of multidrug-resistant S. aureus infections is a global health concern, requiring development of novel therapeutic options. Peptidoglycan-degrading enzymes (peptidoglycan hydrolases, PGHs) have emerged as a highly effective class of antimicrobial proteins against S. aureus and other pathogens. When applied to Gram-positive bacteria, PGHs hydrolyze bonds within the peptidoglycan layer, leading to rapid bacterial death by lysis. This activity is highly specific and independent of the metabolic activity of the cell or its antibiotic resistance patterns. However, systemic application of PGHs is limited by their often low activity in vivo and by an insufficient serum circulation half-life. To address this problem, we aimed to extend the half-life of PGHs selected for high activity against S. aureus in human serum. Half-life extension and increased serum circulation were achieved through fusion of PGHs to an albumin-binding domain (ABD), resulting in high-affinity recruitment of human serum albumin and formation of large protein complexes. Importantly, the ABD-fused PGHs maintained high killing activity against multiple drug-resistant S. aureus strains, as determined by ex vivo testing in human blood. The top candidate, termed ABD_M23, was tested in vivo to treat S. aureus-induced murine bacteremia. Our findings demonstrate a significantly higher efficacy of ABD_M23 than of the parental M23 enzyme. We conclude that fusion with ABD represents a powerful approach for half-life extension of PGHs, expanding the therapeutic potential of these enzybiotics for treatment of multidrug-resistant bacterial infections.IMPORTANCE Life-threatening infections with Staphylococcus aureus are often difficult to treat due to the increasing prevalence of antibiotic-resistant bacteria and their ability to persist in protected niches in the body. Bacteriolytic enzymes are promising new antimicrobials because they rapidly kill bacteria, including drug-resistant and persisting cells, by destroying their cell wall. However, when injected into the bloodstream, these enzymes are not retained long enough to clear an infection. Here, we describe a modification to increase blood circulation time of the enzymes and enhance treatment efficacy against S. aureus-induced bloodstream infections. This was achieved by preselecting enzyme candidates for high activity in human blood and coupling them to serum albumin, thereby preventing their elimination by kidney filtration and blood vessel cells.
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8
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Tham HY, Song AAL, Yusoff K, Tan GH. Effect of different cloning strategies in pET-28a on solubility and functionality of a staphylococcal phage endolysin. Biotechniques 2020; 69:161-170. [PMID: 32787565 DOI: 10.2144/btn-2020-0034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Endolysins have been studied intensively as an alternative to antibiotics. In this study, endolysin derived from a phage which infects methicillin-resistant Staphylococcus aureus (MRSA) was cloned and expressed in Escherichia coli pET28a. Initially, the endolysin was cloned using BamHI/XhoI, resulting in expression of a recombinant endolysin which was expressed in inclusion bodies. While solubilization was successful, the protein remained nonfunctional. Recloning the endolysin using NcoI/XhoI resulted in expression of soluble and functional proteins at 18°C. The endolysin was able to form halo zones on MRSA plates and showed a reduction in turbidity of MRSA growth. Therefore, cloning strategies should be chosen carefully even in an established expression system as they could greatly affect the functionality of the expressed protein.
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Affiliation(s)
- Hong Y Tham
- Department of Microbiology, Faculty of Biotechnology & Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Adelene A-L Song
- Department of Microbiology, Faculty of Biotechnology & Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.,Institute of Bioscience, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Khatijah Yusoff
- Department of Microbiology, Faculty of Biotechnology & Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.,Institute of Bioscience, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Geok H Tan
- Institute of Bioscience, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.,Department of Agriculture Technology, Faculty of Agriculture, University Putra Malaysia, 43400, Serdang, Selangor, Malaysia
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Bacteriophage-Derived Endolysins Applied as Potent Biocontrol Agents to Enhance Food Safety. Microorganisms 2020; 8:microorganisms8050724. [PMID: 32413991 PMCID: PMC7285104 DOI: 10.3390/microorganisms8050724] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 02/04/2023] Open
Abstract
Endolysins, bacteriophage-encoded enzymes, have emerged as antibacterial agents that can be actively applied in food processing systems as food preservatives to control pathogens and ultimately enhance food safety. Endolysins break down bacterial peptidoglycan structures at the terminal step of the phage reproduction cycle to enable phage progeny release. In particular, endolysin treatment is a novel strategy for controlling antibiotic-resistant bacteria, which are a severe and increasingly frequent problem in the food industry. In addition, endolysins can eliminate biofilms on the surfaces of utensils. Furthermore, the cell wall-binding domain of endolysins can be used as a tool for rapidly detecting pathogens. Research to extend the use of endolysins toward Gram-negative bacteria is now being extensively conducted. This review summarizes the trends in endolysin research to date and discusses the future applications of these enzymes as novel food preservation tools in the field of food safety.
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Kaur J, Singh P, Sharma D, Harjai K, Chhibber S. A potent enzybiotic against methicillin-resistant Staphylococcus aureus. Virus Genes 2020; 56:480-497. [DOI: 10.1007/s11262-020-01762-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 04/24/2020] [Indexed: 12/22/2022]
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Genomic Sequencing of High-Efficiency Transducing Streptococcal Bacteriophage A25: Consequences of Escape from Lysogeny. J Bacteriol 2018; 200:JB.00358-18. [PMID: 30224437 DOI: 10.1128/jb.00358-18] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 09/12/2018] [Indexed: 12/26/2022] Open
Abstract
Lytic bacteriophage A25, which infects Streptococcus pyogenes and several related species, has been used to better understand phage-microbe interactions due to its ability to mediate high-efficiency transduction. Most of these studies, however, are decades old and were conducted prior to the advent of next-generation sequencing and bioinformatics. The aim of our study was to gain a better understanding of the mechanism of high-efficiency transduction through analysis of the A25 genome. We show here that phage A25 is related to a family of genome prophages and became a lytic phage following escape from lysogeny. A lambdoid-like residual lysogeny module consisting of an operator site with two promoters and a cro-like antirepressor gene was identified, but the genes for the cI-like repressor and integrase are missing. Additionally, the genetic organization of the A25 genome was found to be modular in nature and similar to that of many prophages of S. pyogenes as well as from other streptococcal species. A study of A25 homology to all annotated prophages within S. pyogenes revealed near identity within the remnant lysogeny module of the A25 phage genome to the corresponding regions in resident prophages of genome strains MGAS10270 (M2), MGAS315 (M3), MGAS10570 (M4), and STAB902 (M4). Host range studies of MGAS10270, MGAS315, and MGAS10750 demonstrated that these strains were resistant to A25 infection. The resistance mechanism of superinfection immunity was confirmed experimentally through complementation of the operator region and cI-like repressor from prophage MGAS10270.2 into susceptible strains SF370, CEM1Δ4 (SF370ΔSpyCIM1), and ATCC 12204, which rendered all three strains resistant to A25 infection. In silico prediction of packaging through homology analysis of the terminase large subunit from bacteriophages within the known packaging mechanism of Gram-positive bacteria as well as the evidence of terminally redundant and/or circularly permuted sequences suggested that A25 grouped with phages employing the less stringent pac-type packaging mechanisms, which likely explains the characteristic A25 high-efficiency transduction capabilities. Only a few examples of lytic phages appearing following loss of part or all of the lysogeny module have been reported previously, and the genetic mosaicism of A25 suggests that this event may not have been a recent one. However, the discovery that this lytic bacteriophage shares some of the genetic pool of S. pyogenes prophages emphasizes the importance of genetic and biological characterization of bacteriophages when selecting phages for therapeutics or disinfectants, as phage-phage and phage-microbe interactions can be complex, requiring more than just assessment of host range and carriage of toxoid or virulence genes.IMPORTANCE Bacteriophages (bacterial viruses) play an important role in the shaping of bacterial populations as well as the dissemination of bacterial genetic material to new strains, resulting in the spread of virulence factors and antibiotic resistance genes. This study identified the genetic origins of Streptococcus pyogenes phage A25 and uncovered the molecular mechanism employed to promote horizontal transfer of DNA by transduction to new strains of this bacterium as well as identified the basis for its host range.
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Fujiki J, Nakamura T, Furusawa T, Ohno H, Takahashi H, Kitana J, Usui M, Higuchi H, Tanji Y, Tamura Y, Iwano H. Characterization of the Lytic Capability of a LysK-Like Endolysin, Lys-phiSA012, Derived from a Polyvalent Staphylococcus aureus Bacteriophage. Pharmaceuticals (Basel) 2018; 11:ph11010025. [PMID: 29495305 PMCID: PMC5874721 DOI: 10.3390/ph11010025] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 02/17/2018] [Accepted: 02/19/2018] [Indexed: 12/19/2022] Open
Abstract
Antibiotic-resistant bacteria (ARB) have spread widely and rapidly, with their increased occurrence corresponding with the increased use of antibiotics. Infections caused by Staphylococcus aureus have a considerable negative impact on human and livestock health. Bacteriophages and their peptidoglycan hydrolytic enzymes (endolysins) have received significant attention as novel approaches against ARB, including S. aureus. In the present study, we purified an endolysin, Lys-phiSA012, which harbors a cysteine/histidine-dependent amidohydrolase/peptidase (CHAP) domain, an amidase domain, and a SH3b cell wall binding domain, derived from a polyvalent S. aureus bacteriophage which we reported previously. We demonstrate that Lys-phiSA012 exhibits high lytic activity towards staphylococcal strains, including methicillin-resistant S. aureus (MRSA). Analysis of deletion mutants showed that only mutants possessing the CHAP and SH3b domains could lyse S. aureus, indicating that lytic activity of the CHAP domain depended on the SH3b domain. The presence of at least 1 mM Ca2+ and 100 µM Zn2+ enhanced the lytic activity of Lys-phiSA012 in a turbidity reduction assay. Furthermore, a minimum inhibitory concentration (MIC) assay showed that the addition of Lys-phiSA012 decreased the MIC of oxacillin. Our results suggest that endolysins are a promising approach for replacing current antimicrobial agents and may contribute to the proper use of antibiotics, leading to the reduction of ARB.
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Affiliation(s)
- Jumpei Fujiki
- Laboratory of Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (J.F.); tomohiro-tobi-@hotmail.co.jp (T.N.); (T.F.); (H.O.); (H.T.); (J.K.)
| | - Tomohiro Nakamura
- Laboratory of Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (J.F.); tomohiro-tobi-@hotmail.co.jp (T.N.); (T.F.); (H.O.); (H.T.); (J.K.)
| | - Takaaki Furusawa
- Laboratory of Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (J.F.); tomohiro-tobi-@hotmail.co.jp (T.N.); (T.F.); (H.O.); (H.T.); (J.K.)
| | - Hazuki Ohno
- Laboratory of Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (J.F.); tomohiro-tobi-@hotmail.co.jp (T.N.); (T.F.); (H.O.); (H.T.); (J.K.)
| | - Hiromichi Takahashi
- Laboratory of Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (J.F.); tomohiro-tobi-@hotmail.co.jp (T.N.); (T.F.); (H.O.); (H.T.); (J.K.)
| | - Junya Kitana
- Laboratory of Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (J.F.); tomohiro-tobi-@hotmail.co.jp (T.N.); (T.F.); (H.O.); (H.T.); (J.K.)
| | - Masaru Usui
- Laboratory of Food Microbiology and Food Safety, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (M.U.); (Y.T.)
| | - Hidetoshi Higuchi
- Laboratory of Veterinary Hygiene, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan;
| | - Yasunori Tanji
- Department of Bioengineering, Tokyo Institute of Technology, Yokohama 226-8502, Japan;
| | - Yutaka Tamura
- Laboratory of Food Microbiology and Food Safety, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (M.U.); (Y.T.)
- Center for Veterinary Drug Development, Rakuno Gakuen University, Ebetsu 069-8501, Japan
| | - Hidetomo Iwano
- Laboratory of Biochemistry, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501, Japan; (J.F.); tomohiro-tobi-@hotmail.co.jp (T.N.); (T.F.); (H.O.); (H.T.); (J.K.)
- Correspondence: ; Fax: +81-11-388-4885
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Borysowski J, Weber-Dabrowska B, Górski A. Bacteriophage Endolysins as a Novel Class of Antibacterial Agents. Exp Biol Med (Maywood) 2016; 231:366-77. [PMID: 16565432 DOI: 10.1177/153537020623100402] [Citation(s) in RCA: 210] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Endolysins are double-stranded DNA bacteriophage-encoded peptidoglycan hydrolases produced in phage-infected bacterial cells toward the end of the lytic cycle. They reach the peptidoglycan through membrane lesions formed by holins and cleave it, thus, inducing lysis of the bacterial cell and enabling progeny virions to be released. Endolysins are also capable of degrading peptidoglycan when applied externally (as purified recombinant proteins) to the bacterial cell wall, which also results in a rapid lysis of the bacterial cell. The unique ability of endolysins to rapidly cleave peptidoglycan in a generally species-specific manner renders them promising potential antibacterial agents. Originally developed with a view to killing bacteria colonizing mucous membranes (with the first report published in 2001), endolysins also hold promise for the treatment of systemic infections. As potential antibacterials, endolysins possess several important features, for instance, a novel mode of action, a narrow antibacterial spectrum, activity against bacteria regardless of their antibiotic sensitivity, and a low probability of developing resistance. However, there is only one report directly comparing the activity of an endolysin with that of an antibiotic, and no general conclusions can be drawn regarding whether lysins are more effective than traditional antibiotics. The results of the first preclinical studies indicate that the most apparent potential problems associated with endolysin therapy (e.g., their immunogenicity, the release of proinflammatory components during bacteriolysis, or the development of resistance), in fact, may not seriously hinder their use. However, all data regarding the safety and therapeutic effectiveness of endolysins obtained from preclinical studies must be ultimately verified by clinical trials. This review discusses the prophylactic and therapeutic applications of endolysins, especially with respect to their potential use in human medicine. Additionally, we outline current knowledge regarding the structure and natural function of the enzymes in phage biology, including the most recent findings.
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Affiliation(s)
- Jan Borysowski
- Department of Clinical Immunology, Institute of Transplantology, the Medical University of Warsaw, 02-006 Warsaw, Poland.
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DUF3380 Domain from a Salmonella Phage Endolysin Shows Potent N-Acetylmuramidase Activity. Appl Environ Microbiol 2016; 82:4975-81. [PMID: 27287318 DOI: 10.1128/aem.00446-16] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/02/2016] [Indexed: 01/14/2023] Open
Abstract
UNLABELLED Bacteriophage-encoded endolysins are highly diverse enzymes that cleave the bacterial peptidoglycan layer. Current research focuses on their potential applications in medicine, in food conservation, and as biotechnological tools. Despite the wealth of applications relying on the use of endolysin, little is known about the enzymatic properties of these enzymes, especially in the case of endolysins of bacteriophages infecting Gram-negative species. Automated genome annotations therefore remain to be confirmed. Here, we report the biochemical analysis and cleavage site determination of a novel Salmonella bacteriophage endolysin, Gp110, which comprises an uncharacterized domain of unknown function (DUF3380; pfam11860) in its C terminus and shows a higher specific activity (34,240 U/μM) than that of 14 previously characterized endolysins active against peptidoglycan from Gram-negative bacteria (corresponding to 1.7- to 364-fold higher activity). Gp110 is a modular endolysin with an optimal pH of enzymatic activity of pH 8 and elevated thermal resistance. Reverse-phase high-performance liquid chromatography (RP-HPLC) analysis coupled to mass spectrometry showed that DUF3380 has N-acetylmuramidase (lysozyme) activity cleaving the β-(1,4) glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine residues. Gp110 is active against directly cross-linked peptidoglycans with various peptide stem compositions, making it an attractive enzyme for developing novel antimicrobial agents. IMPORTANCE We report the functional and biochemical characterization of the Salmonella phage endolysin Gp110. This endolysin has a modular structure with an enzymatically active domain and a cell wall binding domain. The enzymatic activity of this endolysin exceeds that of all other endolysins previously characterized using the same methods. A domain of unknown function (DUF3380) is responsible for this high enzymatic activity. We report that DUF3380 has N-acetylmuramidase activity against directly cross-linked peptidoglycans with various peptide stem compositions. This experimentally verified activity allows better classification and understanding of the enzymatic activities of endolysins, which mostly are inferred by sequence similarities. Three-dimensional structure predictions for Gp110 suggest a fold that is completely different from that of known structures of enzymes with the same peptidoglycan cleavage specificity, making this endolysin quite unique. All of these features, combined with increased thermal resistance, make Gp110 an attractive candidate for engineering novel endolysin-based antibacterials.
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Schmelcher M, Loessner MJ. Bacteriophage endolysins: applications for food safety. Curr Opin Biotechnol 2015; 37:76-87. [PMID: 26707470 DOI: 10.1016/j.copbio.2015.10.005] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 10/12/2015] [Accepted: 10/26/2015] [Indexed: 01/13/2023]
Abstract
Bacteriophage endolysins (peptidoglycan hydrolases) have emerged as a new class of antimicrobial agents useful for controlling bacterial infection or other unwanted contaminations in various fields, particularly in the light of the worldwide increasing frequency of drug-resistant pathogens. This review summarizes and discusses recent developments regarding the use of endolysins for food safety. Besides the use of native and engineered endolysins for controlling bacterial contamination at different points within the food production chain, this also includes the application of high-affinity endolysin-derived cell wall binding domains for rapid detection of pathogenic bacteria. Novel approaches to extend the lytic action of endolysins towards Gram-negative cells will also be highlighted.
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Affiliation(s)
- Mathias Schmelcher
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland
| | - Martin J Loessner
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland.
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Kashani HH, Moniri R. Expression of Recombinant pET22b-LysK-Cysteine/Histidine-Dependent Amidohydrolase/Peptidase Bacteriophage Therapeutic Protein in Escherichia coli BL21 (DE3). Osong Public Health Res Perspect 2015; 6:256-60. [PMID: 26473093 PMCID: PMC4588433 DOI: 10.1016/j.phrp.2015.08.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 08/02/2015] [Accepted: 08/06/2015] [Indexed: 10/31/2022] Open
Abstract
OBJECTIVES Bacteriophage-encoded endolysins are a group of enzymes that act by digesting the peptidoglycan of bacterial cell walls. LysK has been reported to lyse live staphylococcal cultures. LysK proteins containing only the cysteine/histidine-dependent amidohydrolase/peptidase (CHAP) domain has the capability to show lytic activity against live clinical staphylococcal isolates, including methicillin-resistant Staphylococcus aureus (MRSA). The aim of this study was to clone and express LysK-CHAP domain in Escherichia coli BL21 (DE3) using pET22b as a secretion vector. The pET22b plasmid was used, which encoded a pelB secretion signal under the control of the strong bacteriophage T7 promoter. METHODS The E. coli cloning strains DH5α and BL21 (DE3) were grown at 37°C with aeration in the Luria-Bertani medium. A plasmid encoding LysK-CHAP in a pET22b backbone was constructed. The pET22b vector containing LysK-CHAP sequences were digested with NcoI and HindIII restriction enzymes. Cloning accuracy was confirmed by electrophoresis. The pET22b-LysK plasmid was used to transform the E. coli strain BL21. Isopropyl β-d-1-thiogalactopyranoside (IPTG) was added to a final concentration of 1mM to induce T7 RNA polymerase-based expression. Finally, western blot confirmed the expression of target protein. RESULTS In this study, after double digestion of pEX and pET22b vectors with HindIII and NcoI, LysK gene was cloned into two HindIII and NcoI sites in pET22b vector, and then transformed to E. coli DH5α. Cloning was confirmed with double digestion and analyzed with agarose gel. The recombinant pET22b-LysK plasmid was transformed to E. coli BL21 and the expression was induced by IPTG. The expression was confirmed by Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting method. Observation of a 28.5 kDa band confirmed LysK protein expression. CONCLUSION In the present study, LysK-CHAP domain was successfully cloned and expressed at the pET22b vector and E. coli BL21 (DE3).
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Affiliation(s)
- Hamed Haddad Kashani
- Anatomical Sciences Research Center, Kashan University of Medical Sciences, Kashan, Iran
| | - Rezvan Moniri
- Anatomical Sciences Research Center, Kashan University of Medical Sciences, Kashan, Iran
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Schmelcher M, Shen Y, Nelson DC, Eugster MR, Eichenseher F, Hanke DC, Loessner MJ, Dong S, Pritchard DG, Lee JC, Becker SC, Foster-Frey J, Donovan DM. Evolutionarily distinct bacteriophage endolysins featuring conserved peptidoglycan cleavage sites protect mice from MRSA infection. J Antimicrob Chemother 2015; 70:1453-65. [PMID: 25630640 DOI: 10.1093/jac/dku552] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 12/09/2014] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES In the light of increasing drug resistance in Staphylococcus aureus, bacteriophage endolysins [peptidoglycan hydrolases (PGHs)] have been suggested as promising antimicrobial agents. The aim of this study was to determine the antimicrobial activity of nine enzymes representing unique homology groups within a diverse class of staphylococcal PGHs. METHODS PGHs were recombinantly expressed, purified and tested for staphylolytic activity in multiple in vitro assays (zymogram, turbidity reduction assay and plate lysis) and against a comprehensive set of strains (S. aureus and CoNS). PGH cut sites in the staphylococcal peptidoglycan were determined by biochemical assays (Park-Johnson and Ghuysen procedures) and MS analysis. The enzymes were tested for their ability to eradicate static S. aureus biofilms and compared for their efficacy against systemic MRSA infection in a mouse model. RESULTS Despite similar modular architectures and unexpectedly conserved cleavage sites in the peptidoglycan (conferred by evolutionarily divergent catalytic domains), the enzymes displayed varying degrees of in vitro lytic activity against numerous staphylococcal strains, including cell surface mutants and drug-resistant strains, and proved effective against static biofilms. In a mouse model of systemic MRSA infection, six PGHs provided 100% protection from death, with animals being free of clinical signs at the end of the experiment. CONCLUSIONS Our results corroborate the high potential of PGHs for treatment of S. aureus infections and reveal unique antimicrobial and biochemical properties of the different enzymes, suggesting a high diversity of potential applications despite highly conserved peptidoglycan target sites.
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Affiliation(s)
- Mathias Schmelcher
- Animal Biosciences and Biotechnology Laboratory, ANRI, NEA, ARS, USDA, 10300 Baltimore Ave., Beltsville, MD 20705-2350, USA Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland
| | - Yang Shen
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland Institute for Bioscience and Biotechnology Research, University of Maryland, 9600 Gudelsky Drive, Rockville, MD 20850, USA
| | - Daniel C Nelson
- Institute for Bioscience and Biotechnology Research, University of Maryland, 9600 Gudelsky Drive, Rockville, MD 20850, USA Department of Veterinary Medicine, University of Maryland, 8075 Greenmead Drive, College Park, MD 20742, USA
| | - Marcel R Eugster
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland
| | - Fritz Eichenseher
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland
| | - Daniela C Hanke
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland
| | - Martin J Loessner
- Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland
| | - Shengli Dong
- Department of Biochemistry and Molecular Genetics, MCLM 552, University of Alabama at Birmingham, 1530 3rd Ave., Birmingham, AL 35294-0005, USA
| | - David G Pritchard
- Department of Biochemistry and Molecular Genetics, MCLM 552, University of Alabama at Birmingham, 1530 3rd Ave., Birmingham, AL 35294-0005, USA
| | - Jean C Lee
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Stephen C Becker
- Animal Biosciences and Biotechnology Laboratory, ANRI, NEA, ARS, USDA, 10300 Baltimore Ave., Beltsville, MD 20705-2350, USA
| | - Juli Foster-Frey
- Animal Biosciences and Biotechnology Laboratory, ANRI, NEA, ARS, USDA, 10300 Baltimore Ave., Beltsville, MD 20705-2350, USA
| | - David M Donovan
- Animal Biosciences and Biotechnology Laboratory, ANRI, NEA, ARS, USDA, 10300 Baltimore Ave., Beltsville, MD 20705-2350, USA
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Becker SC, Swift S, Korobova O, Schischkova N, Kopylov P, Donovan DM, Abaev I. Lytic activity of the staphylolytic Twort phage endolysin CHAP domain is enhanced by the SH3b cell wall binding domain. FEMS Microbiol Lett 2014; 362:1-8. [PMID: 25790497 DOI: 10.1093/femsle/fnu019] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Increases in the prevalence of antibiotic-resistant strains of Staphylococcus aureus have elicited efforts to develop novel antimicrobials to treat these drug-resistant pathogens. One potential treatment repurposes the lytic enzymes produced by bacteriophages as antimicrobials. The phage Twort endolysin (PlyTW) harbors three domains, a cysteine, histidine-dependent amidohydrolases/peptidase domain (CHAP), an amidase-2 domain and a SH3b-5 cell wall binding domain (CBD). Our results indicate that the CHAP domain alone is necessary and sufficient for lysis of live S. aureus, while the amidase-2 domain is insufficient for cell lysis when provided alone. Loss of the CBD results in ∼10X reduction of enzymatic activity in both turbidity reduction and plate lysis assays compared to the full length protein. Deletion of the amidase-2 domain resulted in a protein (PlyTW Δ172-373) with lytic activity that exceeded the activity of the full length construct in both the turbidity reduction and plate lysis assays. Addition of Ca(2+) enhanced the turbidity reduction activity of both the full length protein and truncation constructs harboring the CHAP domain. Chelation by addition of EDTA or the addition of zinc inhibited the activity of all PlyTW constructs.
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Affiliation(s)
- Stephen C Becker
- Animal Biosciences and Biotechnology Laboratory, BARC, NEA, ARS, USDA, 10300 Baltimore Avenue, Beltsville, MD 20705-2350, USA
| | - Steven Swift
- Animal Biosciences and Biotechnology Laboratory, BARC, NEA, ARS, USDA, 10300 Baltimore Avenue, Beltsville, MD 20705-2350, USA
| | - Olga Korobova
- Federal Budget Institution of Science, State Research Center for Applied Microbiology and Biotechnology, 142279, Obolensk, Serpukhov district, Moscow Region, Russia
| | - Nina Schischkova
- Federal Budget Institution of Science, State Research Center for Applied Microbiology and Biotechnology, 142279, Obolensk, Serpukhov district, Moscow Region, Russia
| | - Pavel Kopylov
- Federal Budget Institution of Science, State Research Center for Applied Microbiology and Biotechnology, 142279, Obolensk, Serpukhov district, Moscow Region, Russia
| | - David M Donovan
- Animal Biosciences and Biotechnology Laboratory, BARC, NEA, ARS, USDA, 10300 Baltimore Avenue, Beltsville, MD 20705-2350, USA
| | - Igor Abaev
- Federal Budget Institution of Science, State Research Center for Applied Microbiology and Biotechnology, 142279, Obolensk, Serpukhov district, Moscow Region, Russia
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Kaźmierczak Z, Górski A, Dąbrowska K. Facing antibiotic resistance: Staphylococcus aureus phages as a medical tool. Viruses 2014; 6:2551-70. [PMID: 24988520 PMCID: PMC4113783 DOI: 10.3390/v6072551] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 06/17/2014] [Accepted: 06/18/2014] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus is a common and often virulent pathogen in humans. This bacterium is widespread, being present on the skin and in the nose of healthy people. Staphylococcus aureus can cause infections with severe outcomes ranging from pustules to sepsis and death. The introduction of antibiotics led to a general belief that the problem of bacterial infections would be solved. Nonetheless, pathogens including staphylococci have evolved mechanisms of drug resistance. Among current attempts to address this problem, phage therapy offers a promising alternative to combat staphylococcal infections. Here, we present an overview of current knowledge on staphylococcal infections and bacteriophages able to kill Staphylococcus, including experimental studies and available data on their clinical use.
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Affiliation(s)
- Zuzanna Kaźmierczak
- Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, ul. R. Weigla 12, Wroclaw 53-114, Poland.
| | - Andrzej Górski
- Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, ul. R. Weigla 12, Wroclaw 53-114, Poland.
| | - Krystyna Dąbrowska
- Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, ul. R. Weigla 12, Wroclaw 53-114, Poland.
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TgaA, a VirB1-like component belonging to a putative type IV secretion system of Bifidobacterium bifidum MIMBb75. Appl Environ Microbiol 2014; 80:5161-9. [PMID: 24951779 DOI: 10.1128/aem.01413-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Bifidobacterium bifidum MIMBb75 is a human intestinal isolate demonstrated to be interactive with the host and efficacious as a probiotic. However, the molecular biology of this microorganism is yet largely unknown. For this reason, we undertook whole-genome sequencing of B. bifidum MIMBb75 to identify potential genetic factors that would explain the metabolic and probiotic attributes of this bacterium. Comparative genomic analysis revealed a 45-kb chromosomal region that comprises 19 putative genes coding for a potential type IV secretion system (T4SS). Thus, we undertook the initial characterization of this genetic region by studying the putative virB1-like gene, named tgaA. Gene tgaA encodes a peptidoglycan lytic enzyme containing two active domains: lytic murein transglycosylase (LT, cd00254.3) and cysteine- and histidine-dependent amidohydrolase/peptidase (CHAP, pfam05257.4). By means of several in vitro assays, we experimentally confirmed that protein TgaA, consistent with its computationally assigned role, has peptidoglycan lytic activity, which is principally associated to the LT domain. Furthermore, immunofluorescence and immunogold labeling showed that the protein TgaA is abundantly expressed on the cell surface of B. bifidum MIMBb75. According to the literature, the T4SSs, which have not been characterized before in bifidobacteria, can have important implications for bacterial cell-to-cell communication as well as cross talk with host cells, justifying the interest for further studies aimed at the investigation of this genetic region.
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Tiwari R, Dhama K, Chakrabort S, Kapoor S. Enzybiotics: New Weapon in the Army of Antimicrobials: A Review. ACTA ACUST UNITED AC 2014. [DOI: 10.3923/ajava.2014.144.163] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Xia G, Wolz C. Phages of Staphylococcus aureus and their impact on host evolution. INFECTION GENETICS AND EVOLUTION 2013; 21:593-601. [PMID: 23660485 DOI: 10.1016/j.meegid.2013.04.022] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Revised: 03/25/2013] [Accepted: 04/18/2013] [Indexed: 01/01/2023]
Abstract
Most of the dissimilarity between Staphylococcus aureus strains is due to the presence of mobile genetic elements such as bacteriophages or pathogenicity islands. These elements provide the bacteria with additional genes that enable them to establish a new lifestyle that is often accompanied by a shift to increased pathogenicity or a jump to a new host. S. aureus phages may carry genes coding for diverse virulence factors such as Panton-Valentine leukocidin, staphylokinase, enterotoxins, chemotaxis-inhibitory proteins, or exfoliative toxins. Phages also mediate the transfer of pathogenicity islands in a highly coordinated manner and are the primary vehicle for the horizontal transfer of chromosomal and extra-chromosomal genes. Here, we summarise recent advances regarding phage classification, genome organisation and function of S. aureus phages with a particular emphasis on their role in the evolution of the bacterial host.
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Affiliation(s)
- Guoqing Xia
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Elfriede-Aulhornstrasse-6, 72076 Tübingen, Germany; German Center for Infection Research (DZIF), Tübingen, Germany
| | - Christiane Wolz
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Elfriede-Aulhornstrasse-6, 72076 Tübingen, Germany.
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Schmelcher M, Donovan DM, Loessner MJ. Bacteriophage endolysins as novel antimicrobials. Future Microbiol 2013; 7:1147-71. [PMID: 23030422 DOI: 10.2217/fmb.12.97] [Citation(s) in RCA: 474] [Impact Index Per Article: 43.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Endolysins are enzymes used by bacteriophages at the end of their replication cycle to degrade the peptidoglycan of the bacterial host from within, resulting in cell lysis and release of progeny virions. Due to the absence of an outer membrane in the Gram-positive bacterial cell wall, endolysins can access the peptidoglycan and destroy these organisms when applied externally, making them interesting antimicrobial candidates, particularly in light of increasing bacterial drug resistance. This article reviews the modular structure of these enzymes, in which cell wall binding and catalytic functions are separated, as well as their mechanism of action, lytic activity and potential as antimicrobials. It particularly focuses on molecular engineering as a means of optimizing endolysins for specific applications, highlights new developments that may render these proteins active against Gram-negative and intracellular pathogens and summarizes the most recent applications of endolysins in the fields of medicine, food safety, agriculture and biotechnology.
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Affiliation(s)
- Mathias Schmelcher
- Institute of Food, Nutrition & Health, ETH Zurich, Schmelzbergstrasse 7, 8092 Zurich, Switzerland
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Abstract
Phages are recognized as the most abundant and diverse entities on the planet. Their diversity is determined predominantly by their dynamic adaptation capacities when confronted with different selective pressures in an endless cycle of coevolution with a widespread group of bacterial hosts. At the end of the infection cycle, progeny virions are confronted with a rigid cell wall that hinders their release into the environment and the opportunity to start a new infection cycle. Consequently, phages encode hydrolytic enzymes, called endolysins, to digest the peptidoglycan. In this work, we bring to light all phage endolysins found in completely sequenced double-stranded nucleic acid phage genomes and uncover clues that explain the phage-endolysin-host ecology that led phages to recruit unique and specialized endolysins.
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Mishra AK, Rawat M, Viswas KN, Abhishek, Kumar S, Reddy M. Expression and lytic efficacy assessment of the Staphylococcus aureus phage SA4 lysin gene. J Vet Sci 2013; 14:37-43. [PMID: 23388442 PMCID: PMC3615230 DOI: 10.4142/jvs.2013.14.1.37] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 08/08/2012] [Indexed: 11/20/2022] Open
Abstract
Treatment of bovine mastitis caused by Staphylococcus (S.) aureus is becoming very difficult due to the emergence of multidrug-resistant strains. Hence, the search for novel therapeutic alternatives has become of great importance. Consequently, bacteriophages and their endolysins have been identified as potential therapeutic alternatives to antibiotic therapy against S. aureus. In the present study, the gene encoding lysin (LysSA4) in S. aureus phage SA4 was cloned and the nucleotide sequence was determined. Sequence analysis of the recombinant clone revealed a single 802-bp open reading frame encoding a partial protein with a calculated mass of 30 kDa. Results of this analysis also indicated that the LysSA4 sequence shared a high homology with endolysin of the GH15 phage and other reported phages. The LysSA4 gene of the SA4 phage was subsequently expressed in Escherichia coli. Recombinant LysSA4 induced the lysis of host bacteria in a spot inoculation test, indicating that the protein was expressed and functionally active. Furthermore, recombinant lysin was found to have lytic activity, albeit a low level, against mastitogenic Staphylococcus isolates of bovine origin. Data from the current study can be used to develop therapeutic tools for treating diseases caused by drug-resistant S. aureus strains.
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Affiliation(s)
- Anil Kumar Mishra
- Animal Health Division, Central Institute for Research Institute on Goats, Farah 281122, India.
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Drulis-Kawa Z, Majkowska-Skrobek G, Maciejewska B, Delattre AS, Lavigne R. Learning from bacteriophages - advantages and limitations of phage and phage-encoded protein applications. Curr Protein Pept Sci 2012; 13:699-722. [PMID: 23305359 PMCID: PMC3594737 DOI: 10.2174/138920312804871193] [Citation(s) in RCA: 161] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 07/12/2012] [Accepted: 09/20/2012] [Indexed: 12/18/2022]
Abstract
The emergence of bacteria resistance to most of the currently available antibiotics has become a critical therapeutic problem. The bacteria causing both hospital and community-acquired infections are most often multidrug resistant. In view of the alarming level of antibiotic resistance between bacterial species and difficulties with treatment, alternative or supportive antibacterial cure has to be developed. The presented review focuses on the major characteristics of bacteriophages and phage-encoded proteins affecting their usefulness as antimicrobial agents. We discuss several issues such as mode of action, pharmacodynamics, pharmacokinetics, resistance and manufacturing aspects of bacteriophages and phage-encoded proteins application.
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Affiliation(s)
- Zuzanna Drulis-Kawa
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland.
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Łobocka M, Hejnowicz MS, Dąbrowski K, Gozdek A, Kosakowski J, Witkowska M, Ulatowska MI, Weber-Dąbrowska B, Kwiatek M, Parasion S, Gawor J, Kosowska H, Głowacka A. Genomics of staphylococcal Twort-like phages--potential therapeutics of the post-antibiotic era. Adv Virus Res 2012; 83:143-216. [PMID: 22748811 DOI: 10.1016/b978-0-12-394438-2.00005-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Polyvalent bacteriophages of the genus Twort-like that infect clinically relevant Staphylococcus strains may be among the most promising phages with potential therapeutic applications. They are obligatorily lytic, infect the majority of Staphylococcus strains in clinical strain collections, propagate efficiently and do not transfer foreign DNA by transduction. Comparative genomic analysis of 11 S. aureus/S. epidermidis Twort-like phages, as presented in this chapter, emphasizes their strikingly high similarity and clear divergence from phage Twort of the same genus, which might have evolved in hosts of a different species group. Genetically, these phages form a relatively isolated group, which minimizes the risk of acquiring potentially harmful genes. The order of genes in core parts of their 127 to 140-kb genomes is conserved and resembles that found in related representatives of the Spounavirinae subfamily of myoviruses. Functions of certain conserved genes can be predicted based on their homology to prototypical genes of model spounavirus SPO1. Deletions in the genomes of certain phages mark genes that are dispensable for phage development. Nearly half of the genes of these phages have no known homologues. Unique genes are mostly located near termini of the virion DNA molecule and are expressed early in phage development as implied by analysis of their potential transcriptional signals. Thus, many of them are likely to play a role in host takeover. Single genes encode homologues of bacterial virulence-associated proteins. They were apparently acquired by a common ancestor of these phages by horizontal gene transfer but presumably evolved towards gaining functions that increase phage infectivity for bacteria or facilitate mature phage release. Major differences between the genomes of S. aureus/S. epidermidis Twort-like phages consist of single nucleotide polymorphisms and insertions/deletions of short stretches of nucleotides, single genes, or introns of group I. Although the number and location of introns may vary between particular phages, intron shuffling is unlikely to be a major factor responsible for specificity differences.
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Affiliation(s)
- Małgorzata Łobocka
- Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
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Abstract
Peptidoglycan (PG) is the major structural component of the bacterial cell wall. Bacteria have autolytic PG hydrolases that allow the cell to grow and divide. A well-studied group of PG hydrolase enzymes are the bacteriophage endolysins. Endolysins are PG-degrading proteins that allow the phage to escape from the bacterial cell during the phage lytic cycle. The endolysins, when purified and exposed to PG externally, can cause "lysis from without." Numerous publications have described how this phenomenon can be used therapeutically as an effective antimicrobial against certain pathogens. Endolysins have a characteristic modular structure, often with multiple lytic and/or cell wall-binding domains (CBDs). They degrade the PG with glycosidase, amidase, endopeptidase, or lytic transglycosylase activities and have been shown to be synergistic with fellow PG hydrolases or a range of other antimicrobials. Due to the coevolution of phage and host, it is thought they are much less likely to invoke resistance. Endolysin engineering has opened a range of new applications for these proteins from food safety to environmental decontamination to more effective antimicrobials that are believed refractory to resistance development. To put phage endolysin work in a broader context, this chapter includes relevant studies of other well-characterized PG hydrolase antimicrobials.
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Schmelcher M, Korobova O, Schischkova N, Kiseleva N, Kopylov P, Pryamchuk S, Donovan DM, Abaev I. Staphylococcus haemolyticus prophage ΦSH2 endolysin relies on cysteine, histidine-dependent amidohydrolases/peptidases activity for lysis 'from without'. J Biotechnol 2012; 162:289-98. [PMID: 23026556 DOI: 10.1016/j.jbiotec.2012.09.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 09/07/2012] [Accepted: 09/18/2012] [Indexed: 10/27/2022]
Abstract
Staphylococcus aureus is an important pathogen, with methicillin-resistant (MRSA) and multi-drug resistant strains becoming increasingly prevalent in both human and veterinary clinics. S. aureus causing bovine mastitis yields high annual losses to the dairy industry. Conventional treatment of mastitis by broad range antibiotics is often not successful and may contribute to development of antibiotic resistance. Bacteriophage endolysins present a promising new source of antimicrobials. The endolysin of prophage ΦSH2 of Staphylococcus haemolyticus strain JCSC1435 (ΦSH2 lysin) is a peptidoglycan hydrolase consisting of two catalytic domains (CHAP and amidase) and an SH3b cell wall binding domain. In this work, we demonstrated its lytic activity against live staphylococcal cells and investigated the contribution of each functional module to bacterial lysis by testing a series of deletion constructs in zymograms and turbidity reduction assays. The CHAP domain exhibited three-fold higher activity than the full length protein and optimum activity in physiological saline. This activity was further enhanced by the presence of bivalent calcium ions. The SH3b domain was shown to be required for full activity of the complete ΦSH2 lysin. The full length enzyme and the CHAP domain showed activity against multiple staphylococcal strains, including MRSA strains, mastitis isolates, and CoNS.
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Affiliation(s)
- Mathias Schmelcher
- ANRI, Agricultural Research Service, US Department of Agriculture, 10300 Baltimore Avenue, Building 230, BARC-EAST, Beltsville, MD 20705, USA
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Borysowski J, Lobocka M, Międzybrodzki R, Weber-Dabrowska B, Górski A. Potential of bacteriophages and their lysins in the treatment of MRSA: current status and future perspectives. BioDrugs 2012; 25:347-55. [PMID: 22050337 DOI: 10.2165/11595610-000000000-00000] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Bacteriophages (phages) are viruses that specifically infect and kill bacteria. Lysins are enzymes of bacteriophage origin that cleave covalent bonds in peptidoglycan, thereby inducing rapid lysis of a bacterial cell. As potential antibacterial agents, phages and lysins have some important features in common, especially the capacity to kill antibiotic-resistant bacteria, a narrow antibacterial range, and lack of toxic effects on mammalian cells. In this article we present the staphylococcal phages and their lysins that can be used to combat methicillin-resistant Staphylococcus aureus (MRSA), one of today's most dangerous pathogens. We also discuss the use of phages as vectors specifically delivering different antibacterial agents to bacterial cells. Experimental data show that both phages and lysins could be effective in the treatment of MRSA.
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Affiliation(s)
- Jan Borysowski
- Department of Clinical Immunology, Transplantation Institute, Warsaw Medical University, Poland.
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Fenton M, Ross P, McAuliffe O, O'Mahony J, Coffey A. Recombinant bacteriophage lysins as antibacterials. Bioeng Bugs 2011; 1:9-16. [PMID: 21327123 DOI: 10.4161/bbug.1.1.9818] [Citation(s) in RCA: 145] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Accepted: 08/14/2009] [Indexed: 01/01/2023] Open
Abstract
With the increasing worldwide prevalence of antibiotic resistant bacteria, bacteriophage endolysins (lysins) represent a very promising novel alternative class of antibacterial in the fight against infectious disease. Lysins are phage-encoded peptidoglycan hydrolases which, when applied exogenously (as purified recombinant proteins) to Gram-positive bacteria, bring about rapid lysis and death of the bacterial cell. A number of studies have recently demonstrated the strong potential of these enzymes in human and veterinary medicine to control and treat pathogens on mucosal surfaces and in systemic infections. They also have potential in diagnostics and detection, bio-defence, elimination of food pathogens and control of phytopathogens. This review discusses the extensive research on recombinant bacteriophage lysins in the context of antibacterials, and looks forward to future development and potential.
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Affiliation(s)
- Mark Fenton
- Department of Biological Sciences, Cork Institute of Technology, Bishopstown, Cork, Ireland
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Structure-based modification of a Clostridium difficile-targeting endolysin affects activity and host range. J Bacteriol 2011; 193:5477-86. [PMID: 21803993 DOI: 10.1128/jb.00439-11] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Endolysin CD27L causes cell lysis of the pathogen Clostridium difficile, a major cause of nosocomial infection. We report a structural and functional analysis of the catalytic activity of CD27L against C. difficile and other bacterial strains. We show that truncation of the endolysin to the N-terminal domain, CD27L1-179, gave an increased lytic activity against cells of C. difficile, while the C-terminal region, CD27L180-270, failed to produce lysis. CD27L1-179 also has increased activity against other bacterial species that are targeted by the full-length protein and in addition was able to lyse some CD27L-insensitive strains. However, CD27L1-179 retained a measure of specificity, failing to lyse a wide range of bacteria. The use of green fluorescent protein (GFP)-labeled proteins demonstrated that both CD27L and CD27L1-179 bound to C. difficile cell walls. The crystal structure of CD27L1-179 confirms that the enzyme is a zinc-dependent N-acetylmuramoyl-l-alanine amidase. A structure-based sequence analysis allowed us to identify four catalytic residues, a proton relay cascade, and a substrate binding pocket. A BLAST search shows that the closest-related amidases almost exclusively target Clostridia. This implied that the catalytic domain alone contained features that target a specific bacterial species. To test this hypothesis, we modified Leu 98 to a Trp residue which is found in an endolysin from a bacteriophage of Listeria monocytogenes (PlyPSA). This mutation in CD27L resulted in an increased activity against selected serotypes of L. monocytogenes, demonstrating the potential to tune the species specificity of the catalytic domain of an endolysin.
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Abstract
The mycobacteriophage Ms6 is a temperate double-stranded DNA (dsDNA) bacteriophage which, in addition to the predicted endolysin (LysA)-holin (Gp4) lysis system, encodes three additional proteins within its lysis module: Gp1, LysB, and Gp5. Ms6 Gp4 was previously described as a class II holin-like protein. By analysis of the amino acid sequence of Gp4, an N-terminal signal-arrest-release (SAR) domain was identified, followed by a typical transmembrane domain (TMD), features which have previously been observed for pinholins. A second putative holin gene (gp5) encoding a protein with a predicted single TMD at the N-terminal region was identified at the end of the Ms6 lytic operon. Neither the putative class II holin nor the single TMD polypeptide could trigger lysis in pairwise combinations with the endolysin LysA in Escherichia coli. One-step growth curves and single-burst-size experiments of different Ms6 derivatives with deletions in different regions of the lysis operon demonstrated that the gene products of gp4 and gp5, although nonessential for phage viability, appear to play a role in controlling the timing of lysis: an Ms6 mutant with a deletion of gp4 (Ms6(Δgp4)) caused slightly accelerated lysis, whereas an Ms6(Δgp5) deletion mutant delayed lysis, which is consistent with holin function. Additionally, cross-linking experiments showed that Ms6 Gp4 and Gp5 oligomerize and that both proteins interact. Our results suggest that in Ms6 infection, the correct and programmed timing of lysis is achieved by the combined action of Gp4 and Gp5.
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Al-Khulaifi Manal M, Amin Aref Nagwa M, Al Salamah AA. Phage typing, PCR amplification for mecA gene, and antibiotic resistance patterns as epidemiologic markers in nosocomial outbreaks of methicillin resistant Staphylococcus aureus. Saudi J Biol Sci 2009; 16:37-49. [PMID: 23961041 DOI: 10.1016/j.sjbs.2009.07.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Staphylococcus aureus is one of the major causes of community and hospital-acquired infections. Bacteriophage considered as a major risk factor acquires S. aureus new virulence genetic elements. A total number of 119 S. aureus isolated from different specimens obtained from (RKH) were distinguished by susceptibility to 19 antimicrobial agents, phage typing, and PCR amplification for mecA gene. All of MRSA isolates harbored mecA gene, except three unique isolates. The predominant phage group is belonging to the (mixed group). Phage group (II) considered as an epidemiological marker correlated to β-lactamase hyper producer isolates. MRSA isolates indicated high prevalence of phage group (II) with highly increase for phage types (Ø3A), which were correlated to the skin. Phage types (Ø80/Ø81) played an important roll in Community Acquired Methicillin Resistant S. aureus (CAMRSA). Three outpatients MRSA isolates had low multiresistance against Bacitracin (Ba) and Fusidic acid (FD), considered as CAMRSA isolates. It was detected that group I typed all FD-resistant MSSA isolates. Phage groups (M) and (II) were found almost to be integrated for Gentamycin (GN) resistance especially phage type (Ø95) which relatively increased up to 20% in MRSA. Tetracycline (TE) resistant isolates typed by groups (II) and (III) in MSSA. Only one isolate resistant to Sulphamethoxazole/Trimethoprim (SXT) was typed by (III/V) alone in MSSA. MRSA isolates resistant to Chloramphenicol (C) and Ba were typed by all groups except (V). It could be concluded that (PERSA) S. aureus isolates from the wound that originated and colonized, and started to build up multi-resistance against the topical treatment antibiotics. In this study, some unique sporadic isolates for both MRSA and MSSA could be used as biological, molecular and epidemiological markers such as prospective tools.
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Affiliation(s)
- M Al-Khulaifi Manal
- King Saud University, College of Science, Botany and Microbiology Department, P.O. Box 22452, Riyadh 11495, Saudi Arabia
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Payne K, Sun Q, Sacchettini J, Hatfull GF. Mycobacteriophage Lysin B is a novel mycolylarabinogalactan esterase. Mol Microbiol 2009; 73:367-81. [PMID: 19555454 DOI: 10.1111/j.1365-2958.2009.06775.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Mycobacteriophages encounter a unique problem among phages of Gram-positive bacteria, in that lysis must not only degrade the peptidoglycan layer but also circumvent a mycolic acid-rich outer membrane covalently attached to the arabinogalactan-peptidoglycan complex. Mycobacteriophages accomplish this by producing two lysis enzymes, Lysin A (LysA) that hydrolyses peptidoglycan, and Lysin B (LysB), a novel mycolylarabinogalactan esterase, that cleaves the mycolylarabinogalactan bond to release free mycolic acids. The D29 LysB structure shows an alpha/beta hydrolase organization with a catalytic triad common to cutinases, but which contains an additional four-helix domain implicated in the binding of lipid substrates. Whereas LysA is essential for mycobacterial lysis, a Giles DeltalysB mutant mycobacteriophage is viable, but defective in the normal timing, progression and completion of host cell lysis. We propose that LysB facilitates lysis by compromising the integrity of the mycobacterial outer membrane linkage to the arabinogalactan-peptidoglycan layer.
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Affiliation(s)
- Kimberly Payne
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
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37
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Phage lysin LysK can be truncated to its CHAP domain and retain lytic activity against live antibiotic-resistant staphylococci. Appl Environ Microbiol 2008; 75:872-4. [PMID: 19047377 DOI: 10.1128/aem.01831-08] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A truncated derivative of the phage endolysin LysK containing only the CHAP (cysteine- and histidine-dependent amidohydrolase/peptidase) domain exhibited lytic activity against live clinical staphylococcal isolates, including methicillin-resistant Staphylococcus aureus. This is the first known report of a truncated phage lysin which retains high lytic activity against live staphylococcal cells.
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Characterization of a T7-like lytic bacteriophage (phiSG-JL2) of Salmonella enterica serovar gallinarum biovar gallinarum. Appl Environ Microbiol 2008; 74:6970-9. [PMID: 18820072 DOI: 10.1128/aem.01088-08] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PhiSG-JL2 is a newly discovered lytic bacteriophage infecting Salmonella enterica serovar Gallinarum biovar Gallinarum but is nonlytic to a rough vaccine strain of serovar Gallinarum biovar Gallinarum (SG-9R), S. enterica serovar Enteritidis, S. enterica serovar Typhimurium, and S. enterica serovar Gallinarum biovar Pullorum. The phiSG-JL2 genome is 38,815 bp in length (GC content, 50.9%; 230-bp-long direct terminal repeats), and 55 putative genes may be transcribed from the same strand. Functions were assigned to 30 genes based on high amino acid similarity to known proteins. Most of the expected proteins except tail fiber (31.9%) and the overall organization of the genomes were similar to those of yersiniophage phiYeO3-12. phiSG-JL2 could be classified as a new T7-like virus and represents the first serovar Gallinarum biovar Gallinarum phage genome to be sequenced. On the basis of intraspecific ratios of nonsynonymous to synonymous nucleotide changes (Pi[a]/Pi[s]), gene 2 encoding the host RNA polymerase inhibitor displayed Darwinian positive selection. Pretreatment of chickens with phiSG-JL2 before intratracheal challenge with wild-type serovar Gallinarum biovar Gallinarum protected most birds from fowl typhoid. Therefore, phiSG-JL2 may be useful for the differentiation of serovar Gallinarum biovar Gallinarum from other Salmonella serotypes, prophylactic application in fowl typhoid control, and understanding of the vertical evolution of T7-like viruses.
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39
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Manoharadas S, Witte A, Bläsi U. Antimicrobial activity of a chimeric enzybiotic towards Staphylococcus aureus. J Biotechnol 2008; 139:118-23. [PMID: 18940209 DOI: 10.1016/j.jbiotec.2008.09.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 09/09/2008] [Accepted: 09/15/2008] [Indexed: 10/21/2022]
Abstract
Phage lytic enzymes (enzybiotics) have gained attention as prospective tools to eradicate Gram-positive pathogens resistant to antibiotics. Attempts to purify the P16 endolysin of Staphylococcus aureus phage P68 were unsuccessful owing to the poor solubility of the protein. To overcome this limitation, we constructed a chimeric endolysin (P16-17) comprised of the inferred N-terminal d-alanyl-glycyl endopeptidase domain and the C-terminal cell wall targeting domain of the S. aureus phage P16 endolysin and the P17 minor coat protein, respectively. The domain swapping approach and the applied purification procedure resulted in soluble P16-17 protein, which exhibited antimicrobial activity towards S. aureus. In addition, P16-17 augmented the antimicrobial efficacy of the antibiotic gentamicin. This synergistic effect could be useful to reduce the effective dose of aminoglycoside antibiotics.
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Affiliation(s)
- Salim Manoharadas
- Max F. Perutz Laboratories, Department of Microbiology and Immunobiology, University of Vienna, Dr. Bohrgasse 9, A-1030 Vienna, Austria
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40
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Obeso JM, Martínez B, Rodríguez A, García P. Lytic activity of the recombinant staphylococcal bacteriophage PhiH5 endolysin active against Staphylococcus aureus in milk. Int J Food Microbiol 2008; 128:212-8. [PMID: 18809219 DOI: 10.1016/j.ijfoodmicro.2008.08.010] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 07/18/2008] [Accepted: 08/19/2008] [Indexed: 11/16/2022]
Abstract
The endolysin gene (lysH5) from the genome of the Staphylococcus aureus bacteriophage PhiH5 was cloned in Escherichia coli and characterized. The lysH5 gene encoded a protein (LysH5) whose calculated molecular mass and pI were 53.7 kDa and 8.7, respectively. Comparative analysis revealed that LysH5 significantly resembled other murein hydrolases encoded by staphylococcal phages. The modular organization of LysH5 comprised three putative domains, namely, CHAP (cysteine, histidine-dependent amidohydrolase/peptidase), amidase (L-muramoyl-L-alanine amidase), and SH3b (cell wall recognition). In turbidity reduction assays, the purified protein lysed bovine and human S. aureus, and human Staphylococcus epidermidis strains. Other bacteria belonging to different genera were not affected. The lytic activity was optimal at pH 7.0, 37 degrees C, and sensitive to high temperatures. The purified protein was able to kill rapidly S. aureus growing in pasteurized milk and the pathogen was not detected after 4 h of incubation at 37 degrees C. As far as we know, this is the first report to assess the antimicrobial activity of a phage endolysin which might be useful for novel biocontrol strategies in dairying.
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Affiliation(s)
- José María Obeso
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Apdo. 85. 33300-Villaviciosa, Asturias, Spain
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41
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Sugahara K, Yokoi KJ, Nakamura Y, Nishino T, Yamakawa A, Taketo A, Kodaira KI. Mutational and biochemical analyses of the endolysin LysgaY encoded by the Lactobacillus gasseri JCM 1131T phage φgaY. Gene 2007; 404:41-52. [DOI: 10.1016/j.gene.2007.08.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Revised: 08/25/2007] [Accepted: 08/27/2007] [Indexed: 10/22/2022]
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42
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Kašpárek P, Pantůček R, Kahánková J, Růžičková V, Doškař J. Genome rearrangements in host-range mutants of the polyvalent staphylococcal bacteriophage 812. Folia Microbiol (Praha) 2007; 52:331-8. [DOI: 10.1007/bf02932087] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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43
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Kretzer JW, Lehmann R, Schmelcher M, Banz M, Kim KP, Korn C, Loessner MJ. Use of high-affinity cell wall-binding domains of bacteriophage endolysins for immobilization and separation of bacterial cells. Appl Environ Microbiol 2007; 73:1992-2000. [PMID: 17277212 PMCID: PMC1828835 DOI: 10.1128/aem.02402-06] [Citation(s) in RCA: 139] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Immobilization and magnetic separation for specific enrichment of microbial cells, such as the pathogen Listeria monocytogenes, depends on the availability of suitable affinity molecules. We report here a novel concept for the immobilization and separation of bacterial cells by replacing antibodies with cell wall-binding domains (CBDs) of bacteriophage-encoded peptidoglycan hydrolases (endolysins). These polypeptide modules very specifically recognize and bind to ligands on the gram-positive cell wall with high affinity. With paramagnetic beads coated with recombinant Listeria phage endolysin-derived CBD molecules, more than 90% of the viable L. monocytogenes cells could be immobilized and recovered from diluted suspensions within 20 to 40 min. Recovery rates were similar for different species and serovars of Listeria and were not affected by the presence of other microorganisms. The CBD-based magnetic separation (CBD-MS) procedure was evaluated for capture and detection of L. monocytogenes from artificially and naturally contaminated food samples. The CBD separation method was shown to be superior to the established standard procedures; it required less time (48 h versus 96 h) and was the more sensitive method. Furthermore, the generalizability of the CBD-MS approach was demonstrated by using specific phage-encoded CBDs specifically recognizing Bacillus cereus and Clostridium perfringens cells, respectively. Altogether, CBD polypeptides represent novel and innovative tools for the binding and capture of bacterial cells, with many possible applications in microbiology and diagnostics.
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Affiliation(s)
- Jan W Kretzer
- Institute of Food Science and Nutrition, ETH Zurich, Schmelzbergstrasse 7, CH-8092 Zurich, Switzerland
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44
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Sass P, Bierbaum G. Lytic activity of recombinant bacteriophage phi11 and phi12 endolysins on whole cells and biofilms of Staphylococcus aureus. Appl Environ Microbiol 2006; 73:347-52. [PMID: 17085695 PMCID: PMC1797112 DOI: 10.1128/aem.01616-06] [Citation(s) in RCA: 163] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The recombinant phi11 endolysin hydrolyzed heat-killed staphylococci as well as staphylococcal biofilms. Cell wall targeting appeared to be a prerequisite for lysis of whole cells, and the combined action of the endopeptidase and amidase domains was necessary for maximum activity. In contrast, the phi12 endolysin was inactive and caused aggregation of the cells.
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Affiliation(s)
- Peter Sass
- Institute for Medical Microbiology, Immunology and Parasitology, University of Bonn, Sigmund-Freud-Strasse 25, 53105 Bonn, Germany
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45
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Korndörfer IP, Danzer J, Schmelcher M, Zimmer M, Skerra A, Loessner MJ. The crystal structure of the bacteriophage PSA endolysin reveals a unique fold responsible for specific recognition of Listeria cell walls. J Mol Biol 2006; 364:678-89. [PMID: 17010991 DOI: 10.1016/j.jmb.2006.08.069] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 08/17/2006] [Accepted: 08/23/2006] [Indexed: 10/24/2022]
Abstract
Bacteriophage murein hydrolases exhibit high specificity towards the cell walls of their host bacteria. This specificity is mostly provided by a structurally well defined cell wall-binding domain that attaches the enzyme to its solid substrate. To gain deeper insight into this mechanism we have crystallized the complete 314 amino acid endolysin from the temperate Listeria monocytogenes phage PSA. The crystal structure of PlyPSA was determined by single wavelength anomalous dispersion methods and refined to 1.8 A resolution. The two functional domains of the polypeptide, providing cell wall-binding and enzymatic activities, can be clearly distinguished and are connected via a linker segment of six amino acid residues. The core of the N-acetylmuramoyl-L-alanine amidase moiety is formed by a twisted, six-stranded beta-sheet flanked by six helices. Although the catalytic domain is unique among the known Listeria phage endolysins, its structure is highly similar to known phosphorylase/hydrolase-like alpha/beta-proteins, including an autolysin amidase from Paenibacillus polymyxa. In contrast, the C-terminal domain of PlyPSA features a novel fold, comprising two copies of a beta-barrel-like motif, which are held together by means of swapped beta-strands. The architecture of the enzyme with its two separate domains explains its unique substrate recognition properties and also provides insight into the lytic mechanisms of related Listeria phage endolysins, a class of enzymes that bear biotechnological potential.
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Affiliation(s)
- Ingo P Korndörfer
- Technische Universität München, Lehrstuhl für Biologische Chemie, An der Saatzucht 5, D-85350 Freising, Germany.
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Delisle AL, Barcak GJ, Guo M. Isolation and expression of the lysis genes of Actinomyces naeslundii phage Av-1. Appl Environ Microbiol 2006; 72:1110-7. [PMID: 16461656 PMCID: PMC1392916 DOI: 10.1128/aem.72.2.1110-1117.2006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Like most gram-positive oral bacteria, Actinomyces naeslundii is resistant to salivary lysozyme and to most other lytic enzymes. We are interested in studying the lysins of phages of this important oral bacterium as potential diagnostic and therapeutic agents. To identify the Actinomyces phage genes encoding these species-specific enzymes in Escherichia coli, we constructed a new cloning vector, pAD330, that can be used to enrich for and isolate phage holin genes, which are located adjacent to the lysin genes in most phage genomes. Cloned holin insert sequences were used to design sequencing primers to identify nearby lysin genes by using whole phage DNA as the template. From partial digestions of A. naeslundii phage Av-1 genomic DNA we were able to clone, in independent experiments, inserts that complemented the defective lambda holin in pAD330, as evidenced by extensive lysis after thermal induction. The DNA sequence of the inserts in these plasmids revealed that both contained the complete lysis region of Av-1, which is comprised of two holin-like genes, designated holA and holB, and an endolysin gene, designated lysA. We were able to subclone and express these genes and determine some of the functional properties of their gene products.
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Affiliation(s)
- Allan L Delisle
- Department of Biomedical Sciences, School of Dentistry, University of Maryland, Baltimore, Baltimore, MD 21201, USA.
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Takáč M, Witte A, Bläsi U. Functional analysis of the lysis genes of Staphylococcus aureus phage P68 in Escherichia coli. MICROBIOLOGY-SGM 2005; 151:2331-2342. [PMID: 16000723 DOI: 10.1099/mic.0.27937-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Double-stranded DNA phages of both Gram-positive and Gram-negative bacteria typically use a holin-endolysin system to achieve lysis of their host. In this study, the lysis genes of Staphylococcus aureus phage P68 were characterized. P68 gene lys16 was shown to encode a cell-wall-degrading enzyme, which causes cell lysis when externally added to clinical isolates of S. aureus. Another gene, hol15, was identified embedded in the -1 reading frame at the 3' end of lys16. The deduced Hol15 protein has three putative transmembrane domains, and thus resembles class I holins. An additional candidate holin gene, hol12, was found downstream of the endolysin gene lys16 based on two predicted transmembrane domains of the encoded protein, which is a typical trait of class II holins. The synthesis of either Hol12 or Hol15 resulted in growth retardation of Escherichia coli, and both hol15 and hol12 were able to complement a phage lambda Sam mutation. The hol15 gene has a dual start motif beginning with the codons Met1-Lys2-Met3.... Evidence is presented that the hol15 gene encodes a lysis inhibitor (anti-holin) and a lysis effector (actual holin). As depolarization of the membrane converted the anti-holin to a functional holin, these studies suggested that hol15 functions as a typical dual start motif class I holin. The unusual arrangement of the P68 lysis genes is discussed.
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Affiliation(s)
- Marian Takáč
- Max F. Perutz Laboratories, Department of Microbiology and Immunobiology, University Departments at the Vienna Biocenter, Dr Bohrgasse 9/4, 1030 Vienna, Austria
| | - Angela Witte
- Max F. Perutz Laboratories, Department of Microbiology and Immunobiology, University Departments at the Vienna Biocenter, Dr Bohrgasse 9/4, 1030 Vienna, Austria
| | - Udo Bläsi
- Max F. Perutz Laboratories, Department of Microbiology and Immunobiology, University Departments at the Vienna Biocenter, Dr Bohrgasse 9/4, 1030 Vienna, Austria
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O'Flaherty S, Coffey A, Meaney W, Fitzgerald GF, Ross RP. The recombinant phage lysin LysK has a broad spectrum of lytic activity against clinically relevant staphylococci, including methicillin-resistant Staphylococcus aureus. J Bacteriol 2005; 187:7161-4. [PMID: 16199588 PMCID: PMC1251611 DOI: 10.1128/jb.187.20.7161-7164.2005] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study concerns the cloning, characterization, and expression of the lysin (LysK) from staphylococcal phage K in Lactococcus lactis. Lactococcal lysates containing recombinant LysK were found to inhibit a range of different species of staphylococci isolated from bovine and human infection sources, including methicillin-resistant Staphylococcus aureus. LysK thus has potential as an antimicrobial for applications in the prevention and/or treatment of infections caused by staphylococci.
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Affiliation(s)
- S O'Flaherty
- Dairy Products Research Centre, Teagasc, Moorepark, Fermoy, Co. Cork, Ireland
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Loessner MJ. Bacteriophage endolysins--current state of research and applications. Curr Opin Microbiol 2005; 8:480-7. [PMID: 15979390 DOI: 10.1016/j.mib.2005.06.002] [Citation(s) in RCA: 362] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2005] [Accepted: 06/09/2005] [Indexed: 11/27/2022]
Abstract
Endolysins are phage-encoded enzymes that break down bacterial peptidoglycan at the terminal stage of the phage reproduction cycle. Their action is tightly regulated by holins, by membrane arrest, and by conversion from their inactive to active state. Recent research has not only revealed the unexpected diversity of these highly specific hydrolases but has also yielded insights into their modular organization and their three-dimensional structures. Their N-terminal catalytic domains are able to target almost every possible bond in the peptidoglycan network, and their corresponding C-terminal cell wall binding domains target the enzymes to their substrate. Owing to their specificity and high activity, endolysins have been employed for various in vitro and in vivo aims, in food science, in microbial diagnostics, and for treatment of experimental infections. Clearly, phage endolysins represent great tools for use in molecular biology, biotechnology and in medicine, and we are just beginning to tap this potential.
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Affiliation(s)
- Martin J Loessner
- Institute of Food Science and Nutrition, Swiss Federal Institute of Technology (ETH), Schmelzbergstrasse 7, CH-8092 Zürich, Switzerland.
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Low LY, Yang C, Perego M, Osterman A, Liddington RC. Structure and lytic activity of a Bacillus anthracis prophage endolysin. J Biol Chem 2005; 280:35433-9. [PMID: 16103125 DOI: 10.1074/jbc.m502723200] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report a structural and functional analysis of the lambda prophage Ba02 endolysin (PlyL) encoded by the Bacillus anthracis genome. We show that PlyL comprises two autonomously folded domains, an N-terminal catalytic domain and a C-terminal cell wall-binding domain. We determined the crystal structure of the catalytic domain; its three-dimensional fold is related to that of the cell wall amidase, T7 lysozyme, and contains a conserved zinc coordination site and other components of the catalytic machinery. We demonstrate that PlyL is an N-acetylmuramoyl-L-alanine amidase that cleaves the cell wall of several Bacillus species when applied exogenously. We show, unexpectedly, that the catalytic domain of PlyL cleaves more efficiently than the full-length protein, except in the case of Bacillus cereus, and using GFP-tagged cell wall-binding domain, we detected strong binding of the cell wall-binding domain to B. cereus but not to other species tested. We further show that a related endolysin (Ply21) from the B. cereus phage, TP21, shows a similar pattern of behavior. To explain these data, and the species specificity of PlyL, we propose that the C-terminal domain inhibits the activity of the catalytic domain through intramolecular interactions that are relieved upon binding of the C-terminal domain to the cell wall. Furthermore, our data show that (when applied exogenously) targeting of the enzyme to the cell wall is not a prerequisite of its lytic activity, which is inherently high. These results may have broad implications for the design of endolysins as therapeutic agents.
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Affiliation(s)
- Lieh Yoon Low
- Infectious and Inflammatory Disease Center, The Burnham Institute, La Jolla, California 92037, USA
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