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Thöneböhn S, Fischer D, Kreiling V, Kemmler A, Oberheim I, Hager F, Schmid NE, Thormann KM. Identifying components of the Shewanella phage LambdaSo lysis system. J Bacteriol 2024; 206:e0002224. [PMID: 38771038 DOI: 10.1128/jb.00022-24] [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: 01/19/2024] [Accepted: 04/26/2024] [Indexed: 05/22/2024] Open
Abstract
Phage-induced lysis of Gram-negative bacterial hosts usually requires a set of phage lysis proteins, a holin, an endopeptidase, and a spanin system, to disrupt each of the three cell envelope layers. Genome annotations and previous studies identified a gene region in the Shewanella oneidensis prophage LambdaSo, which comprises potential holin- and endolysin-encoding genes but lacks an obvious spanin system. By a combination of candidate approaches, mutant screening, characterization, and microscopy, we found that LambdaSo uses a pinholin/signal-anchor-release (SAR) endolysin system to induce proton leakage and degradation of the cell wall. Between the corresponding genes, we found that two extensively nested open-reading frames encode a two-component spanin module Rz/Rz1. Unexpectedly, we identified another factor strictly required for LambdaSo-induced cell lysis, the phage protein Lcc6. Lcc6 is a transmembrane protein of 65 amino acid residues with hitherto unknown function, which acts at the level of holin in the cytoplasmic membrane to allow endolysin release. Thus, LambdaSo-mediated cell lysis requires at least four protein factors (pinholin, SAR endolysin, spanin, and Lcc6). The findings further extend the known repertoire of phage proteins involved in host lysis and phage egress. IMPORTANCE Lysis of bacteria can have multiple consequences, such as the release of host DNA to foster robust biofilm. Phage-induced lysis of Gram-negative cells requires the disruption of three layers, the outer and inner membranes and the cell wall. In most cases, the lysis systems of phages infecting Gram-negative cells comprise holins to disrupt or depolarize the membrane, thereby releasing or activating endolysins, which then degrade the cell wall. This, in turn, allows the spanins to become active and fuse outer and inner membranes, completing cell envelope disruption and allowing phage egress. Here, we show that the presence of these three components may not be sufficient to allow cell lysis, implicating that also in known phages, further factors may be required.
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Affiliation(s)
- Svenja Thöneböhn
- Institute of Microbiology and Molecular Biology, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Dorian Fischer
- Institute of Microbiology and Molecular Biology, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Vanessa Kreiling
- Institute of Microbiology and Molecular Biology, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Alina Kemmler
- Institute of Microbiology and Molecular Biology, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Isabella Oberheim
- Institute of Microbiology and Molecular Biology, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Fabian Hager
- Institute of Microbiology and Molecular Biology, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Nicole E Schmid
- Institute of Microbiology and Molecular Biology, Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Kai M Thormann
- Institute of Microbiology and Molecular Biology, Justus-Liebig-Universität Gießen, Gießen, Germany
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2
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Zheng T, Zhang C. Engineering strategies and challenges of endolysin as an antibacterial agent against Gram-negative bacteria. Microb Biotechnol 2024; 17:e14465. [PMID: 38593316 PMCID: PMC11003714 DOI: 10.1111/1751-7915.14465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/09/2024] [Accepted: 03/21/2024] [Indexed: 04/11/2024] Open
Abstract
Bacteriophage endolysin is a novel antibacterial agent that has attracted much attention in the prevention and control of drug-resistant bacteria due to its unique mechanism of hydrolysing peptidoglycans. Although endolysin exhibits excellent bactericidal effects on Gram-positive bacteria, the presence of the outer membrane of Gram-negative bacteria makes it difficult to lyse them extracellularly, thus limiting their application field. To enhance the extracellular activity of endolysin and facilitate its crossing through the outer membrane of Gram-negative bacteria, researchers have adopted physical, chemical, and molecular methods. This review summarizes the characterization of endolysin targeting Gram-negative bacteria, strategies for endolysin modification, and the challenges and future of engineering endolysin against Gram-negative bacteria in clinical applications, to promote the application of endolysin in the prevention and control of Gram-negative bacteria.
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Affiliation(s)
- Tianyu Zheng
- Bathurst Future Agri‐Tech InstituteQingdao Agricultural UniversityQingdaoChina
| | - Can Zhang
- College of Veterinary MedicineQingdao Agricultural UniversityQingdaoChina
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3
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Premetis GE, Georgakis ND, Stathi A, Labrou NE. Metaviromics analysis of marine biofilm reveals a glycoside hydrolase endolysin with high specificity towards Acinetobacter baumannii. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2023; 1871:140918. [PMID: 37150474 DOI: 10.1016/j.bbapap.2023.140918] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/27/2023] [Accepted: 05/02/2023] [Indexed: 05/09/2023]
Abstract
Multidrug-resistant (MDR) bacteria are a growing threat to the public health. Among them, the Gram-negative Acinetobacter baumannii is considered today as the most dangerous MDR pathogen. Phage-derived endolysins are peptidoglycan (PG) hydrolytic enzymes that can function as effective tools in the fight against MDR bacteria. In the present work, the viral diversity of a marine environmental sample (biofilm), formed near an industrial zone, was mined for the identification of a putative endolysin (AbLys2) that belongs to the glycoside hydrolase family 24 (GH24, EC 3.2.1.17). The coding sequence of AbLys2 was cloned and expressed in E. coli. The lytic activity and specificity of the recombinant enzyme were evaluated against suspensions of a range of Gram-positive and Gram-negative human pathogens using turbidity assays. AbLys2 displayed enhanced selectivity towards A. baumannii cells, compared to other bacteria. Kinetics analysis was carried out to characterize the dependence of its lytic activity on pH and showed that the enzyme exhibits its maximal activity at pH 5.5. Thermostability analysis showed that AbLys2 displays melting temperature Tm 47.1 °C. Florescence microscopy and cell viability assays established that AbLys2 is active towards live cultures of A. baumannii cells with an inhibitory concentration IC50 3.41 ± 0.09 μM. Molecular modeling allowed the prediction of important amino acid residues involved in catalysis. The results of the present study suggest that AbLys2 provides efficient lytic and antimicrobial activity towards A. baumannii cells and therefore is a promising new antimicrobial against this pathogen.
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Affiliation(s)
- Georgios E Premetis
- Laboratory of Enzyme Technology, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, 75 Iera Odos Street, GR-11855 -Athens, Greece
| | - Nikolaos D Georgakis
- Laboratory of Enzyme Technology, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, 75 Iera Odos Street, GR-11855 -Athens, Greece
| | - Angeliki Stathi
- Department of Microbiology, "Aghia Sophia" Children's Hospital, 11527 Athens, Greece
| | - Nikolaos E Labrou
- Laboratory of Enzyme Technology, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, 75 Iera Odos Street, GR-11855 -Athens, Greece.
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4
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Chen K, Guan Y, Hu R, Cui X, Liu Q. Characterization of the LysP2110-HolP2110 Lysis System in Ralstonia solanacearum Phage P2110. Int J Mol Sci 2023; 24:10375. [PMID: 37373522 DOI: 10.3390/ijms241210375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/14/2023] [Accepted: 06/18/2023] [Indexed: 06/29/2023] Open
Abstract
Ralstonia solanacearum, a pathogen causing widespread bacterial wilt disease in numerous crops, currently lacks an optimal control agent. Given the limitations of traditional chemical control methods, including the risk of engendering drug-resistant strains and environmental harm, there is a dire need for sustainable alternatives. One alternative is lysin proteins that selectively lyse bacteria without contributing to resistance development. This work explored the biocontrol potential of the LysP2110-HolP2110 system of Ralstonia solanacearum phage P2110. Bioinformatics analyses pinpointed this system as the primary phage-mediated host cell lysis mechanism. Our data suggest that LysP2110, a member of the Muraidase superfamily, requires HolP2110 for efficient bacterial lysis, presumably via translocation across the bacterial membrane. LysP2110 also exhibits broad-spectrum antibacterial activity in the presence of the outer membrane permeabilizer EDTA. Additionally, we identified HolP2110 as a distinct holin structure unique to the Ralstonia phages, underscoring its crucial role in controlling bacterial lysis through its effect on bacterial ATP levels. These findings provide valuable insights into the function of the LysP2110-HolP2110 lysis system and establish LysP2110 as a promising antimicrobial agent for biocontrol applications. This study underpins the potential of these findings in developing effective and environment-friendly biocontrol strategies against bacterial wilt and other crop diseases.
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Affiliation(s)
- Kaihong Chen
- College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Yanhui Guan
- College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Ronghua Hu
- College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Xiaodong Cui
- College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Qiongguang Liu
- College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
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5
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Tu Q, Pu M, Li Y, Wang Y, Li M, Song L, Li M, An X, Fan H, Tong Y. Acinetobacter Baumannii Phages: Past, Present and Future. Viruses 2023; 15:v15030673. [PMID: 36992382 PMCID: PMC10057898 DOI: 10.3390/v15030673] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/23/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023] Open
Abstract
Acinetobacter baumannii (A. baumannii) is one of the most common clinical pathogens and a typical multi-drug resistant (MDR) bacterium. With the increase of drug-resistant A. baumannii infections, it is urgent to find some new treatment strategies, such as phage therapy. In this paper, we described the different drug resistances of A. baumannii and some basic properties of A. baumannii phages, analyzed the interaction between phages and their hosts, and focused on A. baumannii phage therapies. Finally, we discussed the chance and challenge of phage therapy. This paper aims to provide a more comprehensive understanding of A. baumannii phages and theoretical support for the clinical application of A. baumannii phages.
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Affiliation(s)
- Qihang Tu
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Mingfang Pu
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yahao Li
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering (BAIC-SM), Beijing University of Chemical Technology, Beijing 100029, China
| | - Yuer Wang
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Maochen Li
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Lihua Song
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Mengzhe Li
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Xiaoping An
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Huahao Fan
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
- Correspondence: (H.F.); (Y.T.)
| | - Yigang Tong
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering (BAIC-SM), Beijing University of Chemical Technology, Beijing 100029, China
- Correspondence: (H.F.); (Y.T.)
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6
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Chakravarty D, Schafer JW, Porter LL. Distinguishing features of fold-switching proteins. Protein Sci 2023; 32:e4596. [PMID: 36782353 PMCID: PMC9951197 DOI: 10.1002/pro.4596] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/30/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023]
Abstract
Though many folded proteins assume one stable structure that performs one function, a small-but-increasing number remodel their secondary and tertiary structures and change their functions in response to cellular stimuli. These fold-switching proteins regulate biological processes and are associated with autoimmune dysfunction, severe acute respiratory syndrome coronavirus-2 infection, and more. Despite their biological importance, it is difficult to computationally predict fold switching. With the aim of advancing computational prediction and experimental characterization of fold switchers, this review discusses several features that distinguish fold-switching proteins from their single-fold and intrinsically disordered counterparts. First, the isolated structures of fold switchers are less stable and more heterogeneous than single folders but more stable and less heterogeneous than intrinsically disordered proteins (IDPs). Second, the sequences of single fold, fold switching, and intrinsically disordered proteins can evolve at distinct rates. Third, proteins from these three classes are best predicted using different computational techniques. Finally, late-breaking results suggest that single folders, fold switchers, and IDPs have distinct patterns of residue-residue coevolution. The review closes by discussing high-throughput and medium-throughput experimental approaches that might be used to identify new fold-switching proteins.
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Affiliation(s)
- Devlina Chakravarty
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of HealthBethesdaMarylandUSA
| | - Joseph W. Schafer
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of HealthBethesdaMarylandUSA
| | - Lauren L. Porter
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of HealthBethesdaMarylandUSA
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaMarylandUSA
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7
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Kim Y, Lee SM, Nong LK, Kim J, Kim SB, Kim D. Characterization of Klebsiella pneumoniae bacteriophages, KP1 and KP12, with deep learning-based structure prediction. Front Microbiol 2023; 13:990910. [PMID: 36762092 PMCID: PMC9902359 DOI: 10.3389/fmicb.2022.990910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 12/19/2022] [Indexed: 01/26/2023] Open
Abstract
Concerns over Klebsiella pneumoniae resistance to the last-line antibiotic treatment have prompted a reconsideration of bacteriophage therapy in public health. Biotechnological application of phages and their gene products as an alternative to antibiotics necessitates the understanding of their genomic context. This study sequenced, annotated, characterized, and compared two Klebsiella phages, KP1 and KP12. Physiological validations identified KP1 and KP12 as members of Myoviridae family. Both phages showed that their activities were stable in a wide range of pH and temperature. They exhibit a host specificity toward K. pneumoniae with a broad intraspecies host range. General features of genome size, coding density, percentage GC content, and phylogenetic analyses revealed that these bacteriophages are distantly related. Phage lytic proteins (endolysin, anti-/holin, spanin) identified by the local alignment against different databases, were subjected to further bioinformatic analyses including three-dimensional (3D) structure prediction by AlphaFold. AlphaFold models of phage lysis proteins were consistent with the published X-ray crystal structures, suggesting the presence of T4-like and P1/P2-like bacteriophage lysis proteins in KP1 and KP12, respectively. By providing the primary sequence information, this study contributes novel bacteriophages for research and development pipelines of phage therapy that ultimately, cater to the unmet clinical and industrial needs against K. pneumoniae pathogens.
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Affiliation(s)
- Youngju Kim
- Optipharm Inc., Cheongju-si, Chungcheongbuk-do, Republic of Korea,Department of Microbiology and Molecular Biology, College of Biological Science and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
| | - Sang-Mok Lee
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Linh Khanh Nong
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Jaehyung Kim
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Seung Bum Kim
- Department of Microbiology and Molecular Biology, College of Biological Science and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
| | - Donghyuk Kim
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea,*Correspondence: Donghyuk Kim,
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8
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Feiss M, Young R, Ramsey J, Adhya S, Georgopoulos C, Hendrix RW, Hatfull GF, Gilcrease EB, Casjens SR. Hybrid Vigor: Importance of Hybrid λ Phages in Early Insights in Molecular Biology. Microbiol Mol Biol Rev 2022; 86:e0012421. [PMID: 36165780 PMCID: PMC9799177 DOI: 10.1128/mmbr.00124-21] [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] [Indexed: 01/01/2023] Open
Abstract
Laboratory-generated hybrids between phage λ and related phages played a seminal role in establishment of the λ model system, which, in turn, served to develop many of the foundational concepts of molecular biology, including gene structure and control. Important λ hybrids with phages 21 and 434 were the earliest of such phages. To understand the biology of these hybrids in full detail, we determined the complete genome sequences of phages 21 and 434. Although both genomes are canonical members of the λ-like phage family, they both carry unsuspected bacterial virulence gene types not previously described in this group of phages. In addition, we determined the sequences of the hybrid phages λ imm21, λ imm434, and λ h434 imm21. These sequences show that the replacements of λ DNA by nonhomologous segments of 21 or 434 DNA occurred through homologous recombination in adjacent sequences that are nearly identical in the parental phages. These five genome sequences correct a number of errors in published sequence fragments of the 21 and 434 genomes, and they point out nine nucleotide differences from Sanger's original λ sequence that are likely present in most extant λ strains in laboratory use today. We discuss the historical importance of these hybrid phages in the development of fundamental tenets of molecular biology and in some of the earliest gene cloning vectors. The 434 and 21 genomes reinforce the conclusion that the genomes of essentially all natural λ-like phages are mosaics of sequence modules from a pool of exchangeable segments.
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Affiliation(s)
- Michael Feiss
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Ryland Young
- Center for Phage Technology, Texas A&M AgriLife Research, College Station, Texas, USA
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Jolene Ramsey
- Center for Phage Technology, Texas A&M AgriLife Research, College Station, Texas, USA
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Sankar Adhya
- Laboratory of Molecular Biology, Center for Cancer Research, The National Cancer Institute, Bethesda, Maryland, USA
| | - Costa Georgopoulos
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Roger W. Hendrix
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Pittsburgh Bacteriophage Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Graham F. Hatfull
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Pittsburgh Bacteriophage Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Eddie B. Gilcrease
- Department of Civil and Environmental Engineering, University of Utah, Salt Lake City, Utah, USA
| | - Sherwood R. Casjens
- Division of Microbiology and Immunology, Pathology Department, University of Utah School of Medicine, Salt Lake City, Utah, USA
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, USA
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9
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Abeysekera GS, Love MJ, Manners SH, Billington C, Dobson RCJ. Bacteriophage-encoded lethal membrane disruptors: Advances in understanding and potential applications. Front Microbiol 2022; 13:1044143. [PMID: 36345304 PMCID: PMC9636201 DOI: 10.3389/fmicb.2022.1044143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 10/10/2022] [Indexed: 09/09/2023] Open
Abstract
Holins and spanins are bacteriophage-encoded membrane proteins that control bacterial cell lysis in the final stage of the bacteriophage reproductive cycle. Due to their efficient mechanisms for lethal membrane disruption, these proteins are gaining interest in many fields, including the medical, food, biotechnological, and pharmaceutical fields. However, investigating these lethal proteins is challenging due to their toxicity in bacterial expression systems and the resultant low protein yields have hindered their analysis compared to other cell lytic proteins. Therefore, the structural and dynamic properties of holins and spanins in their native environment are not well-understood. In this article we describe recent advances in the classification, purification, and analysis of holin and spanin proteins, which are beginning to overcome the technical barriers to understanding these lethal membrane disrupting proteins, and through this, unlock many potential biotechnological applications.
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Affiliation(s)
- Gayan S. Abeysekera
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Michael J. Love
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- Health and Environment Group, Institute of Environmental Science and Research, Christchurch, New Zealand
| | - Sarah H. Manners
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Craig Billington
- Health and Environment Group, Institute of Environmental Science and Research, Christchurch, New Zealand
| | - Renwick C. J. Dobson
- Biomolecular Interaction Centre and School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, VIC, Australia
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10
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Meng LH, Ke F, Zhang QY, Zhao Z. Functional Analysis of the Endopeptidase and Holin From Planktothrix agardhii Cyanophage PaV-LD. Front Microbiol 2022; 13:849492. [PMID: 35572663 PMCID: PMC9096620 DOI: 10.3389/fmicb.2022.849492] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/22/2022] [Indexed: 11/13/2022] Open
Abstract
A cyanophage PaV-LD, previously isolated from harmful filamentous cyanobacterium Planktothrix agardhii, was sequenced, and co-expression of its two ORFs in tandem, ORF123 and ORF124, inhibited growth on the model cyanobacterium Synechocystis sp. PCC6803 cells. However, the mechanism of action of ORF123 and ORF124 alone remains to be elucidated. In this study, we aimed to study the individual function of ORF123 or ORF124 from PaV-LD. Our data showed that the ORF123 encoded an endopeptidase, which harbored an M23 family peptidase domain and a transmembrane region. The expression of the endopeptidase in Escherichia coli alone revealed that the protein exhibited remarkable bacteriostatic activity, as evidenced by observation of growth inhibition, membrane damage, and leakage of the intracellular enzyme. Similarly, the holin, a membrane-associated protein encoded by the ORF124, showed weak bacteriostatic activity on E. coli. Moreover, deletion mutations indicated that the transmembrane domains of endopeptidase and holin were indispensable for their bacteriostatic activity. Meanwhile, the bacteriostatic functions of endopeptidase and holin on cyanobacteria cells were confirmed by expressing them in the cyanobacterium Synechocystis sp. PCC6803. Collectively, our study revealed the individual role of endopeptidase or holin and their synergistic bacteriolytic effect, which would contribute to a better understanding of the lytic mechanism of cyanophage PaV-LD.
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Affiliation(s)
- Li-Hui Meng
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China.,State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Fei Ke
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Qi-Ya Zhang
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China.,State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Zhe Zhao
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
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11
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Gontijo MTP, Teles MP, Vidigal PMP, Brocchi M. Expanding the Database of Signal-Anchor-Release Domain Endolysins Through Metagenomics. Probiotics Antimicrob Proteins 2022; 14:603-612. [PMID: 35525881 DOI: 10.1007/s12602-022-09948-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2022] [Indexed: 10/18/2022]
Abstract
Endolysins are bacteriophage-derived lytic enzymes with antimicrobial activity. The action of endolysins against Gram-negative bacteria remains a challenge due to the physical protection of the outer membrane. However, recent research has demonstrated that signal-anchor-release (SAR) endolysins permeate the outer membrane of Gram-negative bacteria. This study investigates 2628 putative endolysin genes identified in 183,298 bacteriophage genomes. Previously, bioinformatic approaches resulted in a database of 66 SAR endolysins. This manuscript almost doubles the list with 53 additional SAR endolysin candidates. Forty-eight of the putative SAR endolysins described in this study contained one muramidase catalytic domain, and five included additional cell wall-binding domains at the C-terminus. For the moment, SAR domains are found in four protein families: glycoside hydrolase family 19 (GH19), glycoside hydrolase family 24 (GH24), glycoside hydrolase family 25 (GH25), and glycoside hydrolase family 108 (GH108). These SAR lysis are clustered in eight groups based on biochemical properties and domain presence/absence. Therefore, in this study, we expand the arsenal of endolysin candidates that might act against Gram-negative bacteria and develop a consult database for antimicrobial proteins derived from bacteriophages.
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Affiliation(s)
- Marco Túlio Pardini Gontijo
- Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Rua Monteiro Lobato 255, Campinas, São Paulo, 13083-862, Brazil.
| | - Mateus Pereira Teles
- Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Rua Monteiro Lobato 255, Campinas, São Paulo, 13083-862, Brazil.,Faculdade de Farmácia, Universidade Estadual de Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Rua Cândido Portinari 200, Campinas, São Paulo, 13083-862, Brazil
| | - Pedro Marcus Pereira Vidigal
- Núcleo de Análise de Biomoléculas (NuBioMol), Universidade Federal de Viçosa (UFV), Vila Gianetti, Casa 21, Campus da UFV, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Marcelo Brocchi
- Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Rua Monteiro Lobato 255, Campinas, São Paulo, 13083-862, Brazil
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12
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Functional Dissection of P1 Bacteriophage Holin-like Proteins Reveals the Biological Sense of P1 Lytic System Complexity. Int J Mol Sci 2022; 23:ijms23084231. [PMID: 35457047 PMCID: PMC9025707 DOI: 10.3390/ijms23084231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 04/01/2022] [Accepted: 04/07/2022] [Indexed: 02/01/2023] Open
Abstract
P1 is a model temperate myovirus. It infects different Enterobacteriaceae and can develop lytically or form lysogens. Only some P1 adaptation strategies to propagate in different hosts are known. An atypical feature of P1 is the number and organization of cell lysis-associated genes. In addition to SAR-endolysin Lyz, holin LydA, and antiholin LydB, P1 encodes other predicted holins, LydC and LydD. LydD is encoded by the same operon as Lyz, LydA and LydB are encoded by an unlinked operon, and LydC is encoded by an operon preceding the lydA gene. By analyzing the phenotypes of P1 mutants in known or predicted holin genes, we show that all the products of these genes cooperate with the P1 SAR-endolysin in cell lysis and that LydD is a pinholin. The contributions of holins/pinholins to cell lysis by P1 appear to vary depending on the host of P1 and the bacterial growth conditions. The pattern of morphological transitions characteristic of SAR-endolysin–pinholin action dominates during lysis by wild-type P1, but in the case of lydC lydD mutant it changes to that characteristic of classical endolysin-pinholin action. We postulate that the complex lytic system facilitates P1 adaptation to various hosts and their growth conditions.
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13
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Identification and Characterization of a New Type of Holin-Endolysin Lysis Cassette in Acidovorax oryzae Phage AP1. Viruses 2022; 14:v14020167. [PMID: 35215761 PMCID: PMC8879335 DOI: 10.3390/v14020167] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 01/04/2022] [Accepted: 01/11/2022] [Indexed: 01/21/2023] Open
Abstract
Phages utilize lysis systems to allow the release of newly assembled viral particles that kill the bacterial host. This is also the case for phage AP1, which infects the rice pathogen Acidovorax oryzae. However, how lysis occurs on a molecular level is currently unknown. We performed in silico bioinformatics analyses, which indicated that the lysis cassette contains a holin (HolAP) and endolysin (LysAP), which are encoded by two adjacent genes. Recombinant expression of LysAP caused Escherichia coli lysis, while HolAP arrested growth. Co-expression of both proteins resulted in enhanced lysis activity compared to the individual proteins alone. Interestingly, LysAP contains a C-terminal region transmembrane domain, which is different from most known endolysins where a N-terminal hydrophobic region is found, with the potential to insert into the membrane. We show that the C-terminal transmembrane domain is crucial for protein localization and bacterial lysis in phage AP1. Our study characterizes the new phage lysis cassette and the mechanism to induce cell disruption, giving new insight in the understanding of phage life cycles.
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14
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Wu Z, Zhang Y, Xu X, Ahmed T, Yang Y, Loh B, Leptihn S, Yan C, Chen J, Li B. The Holin-Endolysin Lysis System of the OP2-Like Phage X2 Infecting Xanthomonas oryzae pv. oryzae. Viruses 2021; 13:v13101949. [PMID: 34696380 PMCID: PMC8541568 DOI: 10.3390/v13101949] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/18/2021] [Accepted: 09/21/2021] [Indexed: 01/01/2023] Open
Abstract
Most endolysins of dsDNA phages are exported by a holin-dependent mechanism, while in some cases endolysins are exported via a holin-independent mechanism. However, it is still unclear whether the same endolysins can be exported by both holin-dependent and holin-independent mechanisms. This study investigated the lysis system of OP2-like phage X2 infecting Xanthomonas oryzae pv. oryzae, causing devastating bacterial leaf blight disease in rice. Based on bioinformatics and protein biochemistry methods, we show that phage X2 employs the classic "holin-endolysin" lysis system. The endolysin acts on the cell envelope and exhibits antibacterial effects in vitro, while the holin facilitates the release of the protein into the periplasm. We also characterized the role of the transmembrane domain (TMD) in the translocation of the endolysin across the inner membrane. We found that the TMD facilitated the translocation of the endolysin via the Sec secretion system. The holin increases the efficiency of protein release, leading to faster and more efficient lysis. Interestingly, in E. coli, the expression of either holin or endolysin with TMDs resulted in the formation of long rod shaped cells. We conclude that the TMD of X2-Lys plays a dual role: One is the transmembrane transport while the other is the inhibition of cell division, resulting in larger cells and thus in a higher number of released viruses per cell.
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Affiliation(s)
- Zhifeng Wu
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Z.W.); (Y.Z.); (X.X.); (T.A.)
| | - Yang Zhang
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Z.W.); (Y.Z.); (X.X.); (T.A.)
| | - Xinyang Xu
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Z.W.); (Y.Z.); (X.X.); (T.A.)
| | - Temoor Ahmed
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Z.W.); (Y.Z.); (X.X.); (T.A.)
| | - Yong Yang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (Y.Y.); (C.Y.)
| | - Belinda Loh
- University of Edinburgh Institute, Zhejiang University, Hangzhou 314400, China; (B.L.); (S.L.)
| | - Sebastian Leptihn
- University of Edinburgh Institute, Zhejiang University, Hangzhou 314400, China; (B.L.); (S.L.)
| | - Chenqi Yan
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (Y.Y.); (C.Y.)
- Institute of Plant Virology, Ningbo University, Ningbo 315211, China
| | - Jianping Chen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (Y.Y.); (C.Y.)
- Institute of Plant Virology, Ningbo University, Ningbo 315211, China
- Correspondence: (J.C.); (B.L.); Tel.: +86-571-8898-2412 (B.L.)
| | - Bin Li
- State Key Laboratory of Rice Biology and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Z.W.); (Y.Z.); (X.X.); (T.A.)
- Correspondence: (J.C.); (B.L.); Tel.: +86-571-8898-2412 (B.L.)
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15
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Das M, Chen N, LiWang A, Wang LP. Identification and characterization of metamorphic proteins: Current and future perspectives. Biopolymers 2021; 112:e23473. [PMID: 34528703 DOI: 10.1002/bip.23473] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 08/09/2021] [Accepted: 08/10/2021] [Indexed: 11/06/2022]
Abstract
Proteins that can reversibly alternate between distinctly different folds under native conditions are described as being metamorphic. The "metamorphome" is the collection of all metamorphic proteins in the proteome, but it remains unknown the extent to which the proteome is populated by this class of proteins. We propose that uncovering the metamorphome will require a synergy of computational screening of protein sequences to identify potential metamorphic behavior and validation through experimental techniques. This perspective discusses computational and experimental approaches that are currently used to predict and characterize metamorphic proteins as well as the need for developing improved methodologies. Since metamorphic proteins act as molecular switches, understanding their properties and behavior could lead to novel applications of these proteins as sensors in biological or environmental contexts.
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Affiliation(s)
- Madhurima Das
- School of Natural Sciences, University of California, Merced, California, USA
| | - Nanhao Chen
- Department of Chemistry, University of California, Davis, California, USA
| | - Andy LiWang
- School of Natural Sciences, University of California, Merced, California, USA.,Department of Chemistry and Biochemistry, University of California, Merced, California, USA.,Center for Cellular and Biomolecular Machines, University of California, Merced, California, USA.,Health Sciences Research Institute, University of California, Merced, California, USA.,Center for Circadian Biology, University of California, San Diego, California, USA
| | - Lee-Ping Wang
- Department of Chemistry, University of California, Davis, California, USA
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16
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Mehner-Breitfeld D, Schwarzkopf JMF, Young R, Kondabagil K, Brüser T. The Phage T4 Antiholin RI Has a Cleavable Signal Peptide, Not a SAR Domain. Front Microbiol 2021; 12:712460. [PMID: 34456892 PMCID: PMC8385771 DOI: 10.3389/fmicb.2021.712460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 07/16/2021] [Indexed: 11/13/2022] Open
Abstract
Holin/endolysin-mediated lysis of phage T4 of Escherichia coli is tightly regulated by the antiholins RI and RIII. While regulation by the cytoplasmic RIII plays a minor role, the periplasmic antiholin RI binds tightly to the holin T and is believed to directly sense periplasmic phage DNA from superinfections as a trigger for the inhibition of lysis. RI has been reported to contain a non-cleavable signal peptide that anchors the protein to the membrane. Lysis is believed to be induced at some stage by a membrane depolarization that causes a release of RI into the periplasm without cleavage of the signal anchor. For the current model of phage lysis induction, it is thus a fundamental assumption that the N-terminal trans-membrane domain (TMD) of RI is such a signal anchor release (SAR) domain. Here we show that, in contrast to previous reports, this domain of RI is a cleavable signal peptide. RI is processed and released into the periplasm as a mature protein, and inactivation of its signal peptidase cleavage site blocks processing and membrane release. The signal peptide of RI can also mediate the normal translocation of a well-characterized Sec substrate, PhoA, into the periplasm. This simplifies the current view of phage lysis regulation and suggests a fundamentally different interpretation of the recently published structure of the soluble domains of the RI–T complex.
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Affiliation(s)
| | | | - Ry Young
- Department of Biochemistry & Biophysics, Center of Phage Technology, Texas A&M University, College Station, TX, United States
| | - Kiran Kondabagil
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Thomas Brüser
- Institute of Microbiology, Leibniz Universität Hannover, Hanover, Germany
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17
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Xu H, Bao X, Hong W, Wang A, Wang K, Dong H, Hou J, Govinden R, Deng B, Chenia HY. Biological Characterization and Evolution of Bacteriophage T7-△holin During the Serial Passage Process. Front Microbiol 2021; 12:705310. [PMID: 34408735 PMCID: PMC8365609 DOI: 10.3389/fmicb.2021.705310] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/28/2021] [Indexed: 11/21/2022] Open
Abstract
Bacteriophage T7 gene 17.5 coding for the only known holin is one of the components of its lysis system, but the holin activity in T7 is more complex than a single gene, and evidence points to the existence of additional T7 genes with holin activity. In this study, a T7 phage with a gene 17.5 deletion (T7-△holin) was rescued and its biological characteristics and effect on cell lysis were determined. Furthermore, the genomic evolution of mutant phage T7-△holin during serial passage was assessed by whole-genome sequencing analysis. It was observed that deletion of gene 17.5 from phage T7 delays lysis time and enlarges the phage burst size; however, this biological characteristic recovered to normal lysis levels during serial passage. Scanning electron microscopy showed that the two opposite ends of E. coli BL21 cells swell post-T7-△holin infection rather than drilling holes on cell membrane when compared with T7 wild-type infection. No visible progeny phage particle accumulation was observed inside the E. coli BL21 cells by transmission electron microscopy. Following serial passage of T7-△holin from the 1st to 20th generations, the mRNA levels of gene 3.5 and gene 19.5 were upregulated and several mutation sites were discovered, especially two missense mutations in gene 19.5, which indicate a potential contribution to the evolution of the T7-△holin. Although the burst size of T7-△holin increased, high titer cultivation of T7-△holin was not achieved by optimizing the culture process. Accordingly, these results suggest that gene 19.5 is a potential lysis-related component that needs to be studied further and that the T7-△holin strain with its gene 17.5 deletion is not adequate to establish the high-titer phage cultivation process.
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Affiliation(s)
- Hai Xu
- Jiangsu Key Laboratory for High-Tech Research and Development of Veterinary Biopharmaceuticals, Jiangsu Agri-Animal Husbandry Vocational College, Taizhou, China.,Institute of Veterinary Immunology & Engineering, Jiangsu Academy of Agricultural Science, Nanjing, China.,School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Durban, South Africa
| | - Xi Bao
- Institute of Veterinary Immunology & Engineering, Jiangsu Academy of Agricultural Science, Nanjing, China
| | - Weiming Hong
- Jiangsu Key Laboratory for High-Tech Research and Development of Veterinary Biopharmaceuticals, Jiangsu Agri-Animal Husbandry Vocational College, Taizhou, China
| | - Anping Wang
- Jiangsu Key Laboratory for High-Tech Research and Development of Veterinary Biopharmaceuticals, Jiangsu Agri-Animal Husbandry Vocational College, Taizhou, China
| | - Kaimin Wang
- Animal, Plant and Food Test Center of Nanjing Customs, Nanjing, China
| | - Hongyan Dong
- Jiangsu Key Laboratory for High-Tech Research and Development of Veterinary Biopharmaceuticals, Jiangsu Agri-Animal Husbandry Vocational College, Taizhou, China
| | - Jibo Hou
- Institute of Veterinary Immunology & Engineering, Jiangsu Academy of Agricultural Science, Nanjing, China
| | - Roshini Govinden
- School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Durban, South Africa
| | - Bihua Deng
- Institute of Veterinary Immunology & Engineering, Jiangsu Academy of Agricultural Science, Nanjing, China.,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Hafizah Y Chenia
- School of Life Sciences, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Durban, South Africa
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18
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Li X, Zhang C, Wei F, Yu F, Zhao Z. Bactericidal activity of a holin-endolysin system derived from Vibrio alginolyticus phage HH109. Microb Pathog 2021; 159:105135. [PMID: 34390766 DOI: 10.1016/j.micpath.2021.105135] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 07/27/2021] [Accepted: 08/09/2021] [Indexed: 11/26/2022]
Abstract
Vibrio alginolyticus is a common opportunistic pathogen that can cause vibriosis of marine aquatic animals. The application of phages or particularly associated protein products for the treatment of vibriosis has shown prominent advantages compared with the treatment with traditional antibiotics. In this study, the function of a holin-endolysin system from V. alginolyticus phage HH109 was characterized by examining the effect of their overexpression on Escherichia coli and V. alginolyticus. Our data revealed that the endolysin of the phage HH109 has stronger bactericidal activity than the holin, as evidenced by observing more cell death and severe structural damage of cells in the endolysin-expressing E. coli. Furthermore, the two proteins displayed the synergistic effect when the holA and lysin were co-expressed in E. coli, although no interaction between them was detected using the bacterial two-hybrid assay. Transmission electron microscopy observation revealed disruptions of cell envelopes accompanied by leakage of intracellular contents. Similarly, the bactericidal activity of the holin and endolysin against V. alginolyticus was also examined whatever the host is sensitive or resistant to phage HH109. Together, our study contributes to a better understanding of the mechanism of phage HH109 destroying the bacterial cell wall to lyse their host and may offer alternative applications potentially for vibriosis treatment.
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Affiliation(s)
- Xixi Li
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, Jiangsu, China
| | - Ce Zhang
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, Jiangsu, China
| | - Fucheng Wei
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, Jiangsu, China
| | - Fei Yu
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, Jiangsu, China
| | - Zhe Zhao
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, Jiangsu, China.
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19
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The Molecular Basis for Escherichia coli O157:H7 Phage FAHEc1 Endolysin Function and Protein Engineering to Increase Thermal Stability. Viruses 2021; 13:v13061101. [PMID: 34207694 PMCID: PMC8228626 DOI: 10.3390/v13061101] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/01/2021] [Accepted: 06/07/2021] [Indexed: 02/02/2023] Open
Abstract
Bacteriophage-encoded endolysins have been identified as antibacterial candidates. However, the development of endolysins as mainstream antibacterial agents first requires a comprehensive biochemical understanding. This study defines the atomic structure and enzymatic function of Escherichia coli O157:H7 phage FAHEc1 endolysin, LysF1. Bioinformatic analysis suggests this endolysin belongs to the T4 Lysozyme (T4L)-like family of proteins and contains a highly conserved catalytic triad. We then solved the structure of LysF1 with x-ray crystallography to 1.71 Å. LysF1 was confirmed to exist as a monomer in solution by sedimentation velocity experiments. The protein architecture of LysF1 is conserved between T4L and related endolysins. Comparative analysis with related endolysins shows that the spatial orientation of the catalytic triad is conserved, suggesting the catalytic mechanism of peptidoglycan degradation is the same as that of T4L. Differences in the sequence illustrate the role coevolution may have in the evolution of this fold. We also demonstrate that by mutating a single residue within the hydrophobic core, the thermal stability of LysF1 can be increased by 9.4 °C without compromising enzymatic activity. Overall, the characterization of LysF1 provides further insight into the T4L-like class of endolysins. Our study will help advance the development of related endolysins as antibacterial agents, as rational engineering will rely on understanding mutable positions within this protein fold.
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20
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Decoding the molecular properties of mycobacteriophage D29 Holin provides insights into Holin engineering. J Virol 2021; 95:JVI.02173-20. [PMID: 33627396 PMCID: PMC8139666 DOI: 10.1128/jvi.02173-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Holins are bacteriophage-encoded small transmembrane proteins that determine the phage infection cycle duration by forming non-specific holes in the host cell membrane at a specific time post-infection. Thus, Holins are also termed as "Protein clocks". Holins have one or more transmembrane domains, and a charged C-terminal region, which, although conserved among Holins, has not yet been examined in detail. Here, we characterize the molecular properties of mycobacteriophage D29 Holin C-terminal region, and investigate the significance of the charged residues and coiled coil (CC) domain present therein. We show that the CC domain is indispensable for Holin-mediated efficient bacterial cell lysis. We further demonstrate that out of the positively- and negatively-charged residues present in the C-terminal region, substituting the former, and not the latter, with serine, renders Holin non-toxic. Moreover, the basic residues present between the 59th and the 79th amino acids are the most crucial for Holin-mediated toxicity. We also constructed an engineered Holin, HolHC, by duplicating the C-terminal region. The HolHC protein shows higher toxicity in both Escherichia coli and Mycobacterium smegmatis, and causes rapid killing of both bacteria upon expression, as compared to the wild-type. A similar oligomerization property of HolHC as the wild-type Holin allows us to propose that the C-terminal region of D29 Holin determines the timing, and not the extent, of oligomerization and, thereby, hole formation. Such knowledge-based engineering of mycobacteriophage Holin will help in developing novel phage-based therapeutics to kill pathogenic mycobacteria, including M. tuberculosis ImportanceHolins are bacteriophage-encoded small membrane perforators that play an important role in determining the timing of host cell lysis towards the end of the phage infection cycle. Holin's ability to precisely time the hole formation in the cell membrane ensuing cell lysis is both interesting and intriguing. Here, we examined the molecular properties of the mycobacteriophage D29 Holin C-terminal region that harbours several polar charged residues and a coiled-coil domain. Our data allowed us to engineer Holin with an ability to rapidly kill bacteria and show higher toxicity than the wild-type protein. Due to their ability to kill host bacteria by membrane disruption, it becomes important to explore the molecular properties of Holins that allow them to function in a timely and efficient manner. Understanding these details can help us modulate Holin activity and engineer bacteriophages with superior lytic properties to kill pathogenic bacteria, curtail infections, and combat antimicrobial resistance.
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21
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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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22
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Steger LME, Kohlmeyer A, Wadhwani P, Bürck J, Strandberg E, Reichert J, Grage SL, Afonin S, Kempfer M, Görner AC, Koch J, Walther TH, Ulrich AS. Structural and functional characterization of the pore-forming domain of pinholin S 2168. Proc Natl Acad Sci U S A 2020; 117:29637-29646. [PMID: 33154156 PMCID: PMC7703622 DOI: 10.1073/pnas.2007979117] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Pinholin S2168 triggers the lytic cycle of bacteriophage φ21 in infected Escherichia coli Activated transmembrane dimers oligomerize into small holes and uncouple the proton gradient. Transmembrane domain 1 (TMD1) regulates this activity, while TMD2 is postulated to form the actual "pinholes." Focusing on the TMD2 fragment, we used synchrotron radiation-based circular dichroism to confirm its α-helical conformation and transmembrane alignment. Solid-state 15N-NMR in oriented DMPC bilayers yielded a helix tilt angle of τ = 14°, a high order parameter (Smol = 0.9), and revealed the azimuthal angle. The resulting rotational orientation places an extended glycine zipper motif (G40xxxS44xxxG48) together with a patch of H-bonding residues (T51, T54, N55) sideways along TMD2, available for helix-helix interactions. Using fluorescence vesicle leakage assays, we demonstrate that TMD2 forms stable holes with an estimated diameter of 2 nm, as long as the glycine zipper motif remains intact. Based on our experimental data, we suggest structural models for the oligomeric pinhole (right-handed heptameric TMD2 bundle), for the active dimer (right-handed Gly-zipped TMD2/TMD2 dimer), and for the full-length pinholin protein before being triggered (Gly-zipped TMD2/TMD1-TMD1/TMD2 dimer in a line).
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Affiliation(s)
- Lena M E Steger
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Annika Kohlmeyer
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Parvesh Wadhwani
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Jochen Bürck
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Erik Strandberg
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Johannes Reichert
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Stephan L Grage
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Sergii Afonin
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Marin Kempfer
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Anne C Görner
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Julia Koch
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Torsten H Walther
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany;
| | - Anne S Ulrich
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany;
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
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Two Distinct Modes of Lysis Regulation in Campylobacter Fletchervirus and Firehammervirus Phages. Viruses 2020; 12:v12111247. [PMID: 33142851 PMCID: PMC7692668 DOI: 10.3390/v12111247] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/22/2020] [Accepted: 10/29/2020] [Indexed: 12/31/2022] Open
Abstract
Campylobacter phages are divided into two genera; Fletchervirus and Firehammervirus, showing only limited intergenus homology. Here, we aim to identify the lytic genes of both genera using two representative phages (F352 and F379) from our collection. We performed a detailed in silico analysis searching for conserved protein domains and found that the predicted lytic genes are not organized into lysis cassettes but are conserved within each genus. To verify the function of selected lytic genes, the proteins were expressed in E. coli, followed by lytic assays. Our results show that Fletchervirus phages encode a typical signal peptide (SP) endolysin dependent on the Sec-pathway for translocation and a holin for activation. In contrast, Firehammervirus phages encode a novel endolysin that does not belong to currently described endolysin groups. This endolysin also uses the Sec-pathway for translocation but induces lysis of E. coli after overexpression. Interestingly, co-expression of this endolysin with an overlapping gene delayed and limited cell lysis, suggesting that this gene functions as a lysis inhibitor. These results indicate that Firehammervirus phages regulate lysis timing by a yet undescribed mechanism. In conclusion, we found that the two Campylobacter phage genera control lysis by two distinct mechanisms.
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Bai J, Lee S, Ryu S. Identification and in vitro Characterization of a Novel Phage Endolysin that Targets Gram-Negative Bacteria. Microorganisms 2020; 8:microorganisms8030447. [PMID: 32245284 PMCID: PMC7143992 DOI: 10.3390/microorganisms8030447] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 03/18/2020] [Accepted: 03/18/2020] [Indexed: 12/22/2022] Open
Abstract
Most double-stranded (ds) DNA phages utilize holin proteins to secrete endolysin for host peptidoglycan lysis. In contrast, several holin-independent endolysins with secretion sequences or signal-arrest-release (SAR) sequences are secreted via the Sec pathway. In this study, we characterized a novel lysis protein (M4Lys) encoded by the dsDNA phage BSPM4, whose lysis function is not dependent on either holin or the Sec pathway in vitro. In silico analysis of M4Lys revealed that it contains a putative virion protein domain and an unusual C-terminal transmembrane domain (TMD). Turbidity reduction assays and liquid chromatography-mass spectrometry using purified peptidoglycan showed that the virion protein domain of M4Lys has peptidoglycan lysis activity. In vitro overproduction of M4Lys in Escherichia coli revealed that M4Lys alone caused rapid cell lysis. Treatment of E. coli with a Sec inhibitor did not inhibit the lysis activity of M4Lys, indicating that the Sec pathway is not involved in M4Lys-mediated cell lysis. Truncation of the TMD eliminated the cell lysis phenomenon, while production of the TMD alone did not induce the cell lysis. All these findings demonstrate that M4Lys is a novel endolysin that has a unique mosaic structure distinct from other canonical endolysins and the TMD plays a critical role in M4Lys-mediated in vitro cell lysis.
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Affiliation(s)
- Jaewoo Bai
- Department of Food and Animal Biotechnology, Seoul National University, Seoul 08826, Korea;
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Korea
- Division of Applied Food System, Major in Food Science & Technology, Seoul Women’s University, Seoul 01797, Korea
| | - Sangmi Lee
- Department of Food and Nutrition, Chungbuk National University, Cheongju, Chungbuk 28644, Korea;
| | - Sangryeol Ryu
- Department of Food and Animal Biotechnology, Seoul National University, Seoul 08826, Korea;
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea
- Center for Food and Bioconvergence, Seoul National University, Seoul 08826, Korea
- Correspondence:
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25
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Ahammad T, Drew DL, Sahu ID, Serafin RA, Clowes KR, Lorigan GA. Continuous Wave Electron Paramagnetic Resonance Spectroscopy Reveals the Structural Topology and Dynamic Properties of Active Pinholin S 2168 in a Lipid Bilayer. J Phys Chem B 2019; 123:8048-8056. [PMID: 31478671 DOI: 10.1021/acs.jpcb.9b06480] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Pinholin S2168 is an essential part of the phage Φ21 lytic protein system to release the virus progeny at the end of the infection cycle. It is known as the simplest natural timing system for its precise control of hole formation in the inner cytoplasmic membrane. Pinholin S2168 is a 68 amino acid integral membrane protein consisting of two transmembrane domains (TMDs) called TMD1 and TMD2. Despite its biological importance, structural and dynamic information of the S2168 protein in a membrane environment is not well understood. Systematic site-directed spin labeling and continuous wave electron paramagnetic resonance (CW-EPR) spectroscopic studies of pinholin S2168 in 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) proteoliposomes are used to reveal the structural topology and dynamic properties in a native-like environment. CW-EPR spectral line-shape analysis of the R1 side chain for 39 residue positions of S2168 indicates that the TMDs have more restricted mobility when compared to the N- and C-termini. CW-EPR power saturation data indicate that TMD1 partially externalizes from the lipid bilayer and interacts with the membrane surface, whereas TMD2 remains buried in the lipid bilayer in the active conformation of pinholin S2168. A tentative structural topology model of pinholin S2168 is also suggested based on EPR spectroscopic data reported in this study.
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Affiliation(s)
- Tanbir Ahammad
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Daniel L Drew
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Indra D Sahu
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Rachel A Serafin
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Katherine R Clowes
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry , Miami University , Oxford , Ohio 45056 , United States
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26
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Mishra S, Looger LL, Porter LL. Inaccurate secondary structure predictions often indicate protein fold switching. Protein Sci 2019; 28:1487-1493. [PMID: 31148305 PMCID: PMC6635839 DOI: 10.1002/pro.3664] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 05/22/2019] [Indexed: 01/08/2023]
Abstract
Although most proteins conform to the classical one‐structure/one‐function paradigm, an increasing number of proteins with dual structures and functions have been discovered. In response to cellular stimuli, such proteins undergo structural changes sufficiently dramatic to remodel even their secondary structures and domain organization. This “fold‐switching” capability fosters protein multi‐functionality, enabling cells to establish tight control over various biochemical processes. Accurate predictions of fold‐switching proteins could both suggest underlying mechanisms for uncharacterized biological processes and reveal potential drug targets. Recently, we developed a prediction method for fold‐switching proteins using structure‐based thermodynamic calculations and discrepancies between predicted and experimentally determined protein secondary structure (Porter and Looger, Proc Natl Acad Sci U S A 2018; 115:5968–5973). Here we seek to leverage the negative information found in these secondary structure prediction discrepancies. To do this, we quantified secondary structure prediction accuracies of 192 known fold‐switching regions (FSRs) within solved protein structures found in the Protein Data Bank (PDB). We find that the secondary structure prediction accuracies for these FSRs vary widely. Inaccurate secondary structure predictions are strongly associated with fold‐switching proteins compared to equally long segments of non‐fold‐switching proteins selected at random. These inaccurate predictions are enriched in helix‐to‐strand and strand‐to‐coil discrepancies. Finally, we find that most proteins with inaccurate secondary structure predictions are underrepresented in the PDB compared with their alternatively folded cognates, suggesting that unequal representation of fold‐switching conformers within the PDB could be an important cause of inaccurate secondary structure predictions. These results demonstrate that inconsistent secondary structure predictions can serve as a useful preliminary marker of fold switching.
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Affiliation(s)
- Soumya Mishra
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, 20147
| | - Loren L Looger
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, 20147
| | - Lauren L Porter
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, 20147
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27
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Abstract
The first steps in phage lysis involve a temporally controlled permeabilization of the cytoplasmic membrane followed by enzymatic degradation of the peptidoglycan. For Caudovirales of Gram-negative hosts, there are two different systems: the holin-endolysin and pinholin-SAR endolysin pathways. In the former, lysis is initiated when the holin forms micron-scale holes in the inner membrane, releasing active endolysin into the periplasm to degrade the peptidoglycan. In the latter, lysis begins when the pinholin causes depolarization of the membrane, which activates the secreted SAR endolysin. Historically, the disruption of the first two barriers of the cell envelope was thought to be necessary and sufficient for lysis of Gram-negative hosts. However, recently a third functional class of lysis proteins, the spanins, has been shown to be required for outer membrane disruption. Spanins are so named because they form a protein bridge that connects both membranes. Most phages produce a two-component spanin complex, composed of an outer membrane lipoprotein (o-spanin) and an inner membrane protein (i-spanin) with a predominantly coiled-coil periplasmic domain. Some phages have a different type of spanin which spans the periplasm as a single molecule, by virtue of an N-terminal lipoprotein signal and a C-terminal transmembrane domain. Evidence is reviewed supporting a model in which the spanins function by fusing the inner membrane and outer membrane. Moreover, it is proposed that spanin function is inhibited by the meshwork of the peptidoglycan, thus coupling the spanin step to the first two steps mediated by the holin and endolysin.
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Affiliation(s)
- Jesse Cahill
- Department of Biochemistry & Biophysics, Center of Phage Technology, Texas A&M University, College Station, TX, United States.
| | - Ry Young
- Department of Biochemistry & Biophysics, Center of Phage Technology, Texas A&M University, College Station, TX, United States
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28
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Haworth NL, Wouters MJ, Hunter MO, Ma L, Wouters MA. Cross-strand disulfides in the hydrogen bonding site of antiparallel β-sheet (aCSDhs): Forbidden disulfides that are highly strained, easily broken. Protein Sci 2018; 28:239-256. [PMID: 30383331 DOI: 10.1002/pro.3545] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 10/30/2018] [Accepted: 10/30/2018] [Indexed: 12/16/2022]
Abstract
Some disulfide bonds perform important structural roles in proteins, but another group has functional roles via redox reactions. Forbidden disulfides are stressed disulfides found in recognizable protein contexts, which currently constitute more than 10% of all disulfides in the PDB. They likely have functional redox roles and constitute a major subset of all redox-active disulfides. The torsional strain of forbidden disulfides is typically higher than for structural disulfides, but not so high as to render them immediately susceptible to reduction under physionormal conditions. Previously we characterized the most abundant forbidden disulfide in the Protein Data Bank, the aCSDn: a canonical motif in which disulfide-bonded cysteine residues are positioned directly opposite each other on adjacent anti-parallel β-strands such that the backbone hydrogen-bonded moieties are directed away from each other. Here we perform a similar analysis for the aCSDh, a less common motif in which the opposed cysteine residues are backbone hydrogen bonded. Oxidation of two Cys in this context places significant strain on the protein system, with the β-chains tilting toward each other to allow disulfide formation. Only left-handed aCSDh conformations are compatible with the inherent right-handed twist of β-sheets. aCSDhs tend to be more highly strained than aCSDns, particularly when both hydrogen bonds are formed. We discuss characterized roles of aCSDh motifs in proteins of the dataset, which include catalytic disulfides in ribonucleotide reductase and ahpC peroxidase as well as a redox-active disulfide in P1 lysozyme, involved in a major conformation change. The dataset also includes many binding proteins.
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Affiliation(s)
- Naomi L Haworth
- Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia.,Structural & Computational Biology Division, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
| | - Michael J Wouters
- Electricity Section, National Measurement Institute, Lindfield, New South Wales, Australia
| | - Morgan O Hunter
- Bioinformatics, Olivia Newton-John Cancer Research Institute, Heidelberg, Victoria, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Victoria, Australia
| | - Lixia Ma
- School of Statistics, Henan University of Economics and Law, Henan Province, China
| | - Merridee A Wouters
- Bioinformatics, Olivia Newton-John Cancer Research Institute, Heidelberg, Victoria, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, Victoria, Australia.,Cancer Data Science, Children's Medical Research Institute, Westmead, New South Wales, Australia
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29
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Kulkarni P, Solomon TL, He Y, Chen Y, Bryan PN, Orban J. Structural metamorphism and polymorphism in proteins on the brink of thermodynamic stability. Protein Sci 2018; 27:1557-1567. [PMID: 30144197 PMCID: PMC6194243 DOI: 10.1002/pro.3458] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 06/11/2018] [Indexed: 12/13/2022]
Abstract
The classical view of the structure-function paradigm advanced by Anfinsen in the 1960s is that a protein's function is inextricably linked to its three-dimensional structure and is encrypted in its amino acid sequence. However, it is now known that a significant fraction of the proteome consists of intrinsically disordered proteins (IDPs). These proteins populate a polymorphic ensemble of conformations rather than a unique structure but are still capable of performing biological functions. At the boundary, between well-ordered and inherently disordered states are proteins that are on the brink of stability, either weakly stable ordered systems or disordered but on the verge of being stable. In such marginal states, even relatively minor changes can significantly alter the energy landscape, leading to large-scale conformational remodeling. Some proteins on the edge of stability are metamorphic, with the capacity to switch from one fold topology to another in response to an environmental trigger (e.g., pH, temperature/salt, redox). Many IDPs, on the other hand, are marginally unstable such that small perturbations (e.g., phosphorylation, ligands) tip the balance over to a range of ordered, partially ordered, or even more disordered states. In general, the structural transitions described by metamorphic fold switches and polymorphic IDPs possess a number of common features including low or diminished stability, large-scale conformational changes, critical disordered regions, latent or attenuated binding sites, and expansion of function. We suggest that these transitions are, therefore, conceptually and mechanistically analogous, representing adjacent regions in the continuum of order/disorder transitions.
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Affiliation(s)
- Prakash Kulkarni
- W. M. Keck Laboratory for Structural BiologyUniversity of Maryland Institute for Bioscience and Biotechnology ResearchRockvilleMaryland20850
| | - Tsega L. Solomon
- W. M. Keck Laboratory for Structural BiologyUniversity of Maryland Institute for Bioscience and Biotechnology ResearchRockvilleMaryland20850
| | - Yanan He
- W. M. Keck Laboratory for Structural BiologyUniversity of Maryland Institute for Bioscience and Biotechnology ResearchRockvilleMaryland20850
| | - Yihong Chen
- W. M. Keck Laboratory for Structural BiologyUniversity of Maryland Institute for Bioscience and Biotechnology ResearchRockvilleMaryland20850
| | - Philip N. Bryan
- W. M. Keck Laboratory for Structural BiologyUniversity of Maryland Institute for Bioscience and Biotechnology ResearchRockvilleMaryland20850
| | - John Orban
- W. M. Keck Laboratory for Structural BiologyUniversity of Maryland Institute for Bioscience and Biotechnology ResearchRockvilleMaryland20850
- Department of Chemistry and BiochemistryUniversity of MarylandCollege ParkMaryland20742
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30
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Enzymes and Mechanisms Employed by Tailed Bacteriophages to Breach the Bacterial Cell Barriers. Viruses 2018; 10:v10080396. [PMID: 30060520 PMCID: PMC6116005 DOI: 10.3390/v10080396] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 07/23/2018] [Accepted: 07/26/2018] [Indexed: 01/07/2023] Open
Abstract
Monoderm bacteria possess a cell envelope made of a cytoplasmic membrane and a cell wall, whereas diderm bacteria have and extra lipid layer, the outer membrane, covering the cell wall. Both cell types can also produce extracellular protective coats composed of polymeric substances like, for example, polysaccharidic capsules. Many of these structures form a tight physical barrier impenetrable by phage virus particles. Tailed phages evolved strategies/functions to overcome the different layers of the bacterial cell envelope, first to deliver the genetic material to the host cell cytoplasm for virus multiplication, and then to release the virion offspring at the end of the reproductive cycle. There is however a major difference between these two crucial steps of the phage infection cycle: virus entry cannot compromise cell viability, whereas effective virion progeny release requires host cell lysis. Here we present an overview of the viral structures, key protein players and mechanisms underlying phage DNA entry to bacteria, and then escape of the newly-formed virus particles from infected hosts. Understanding the biological context and mode of action of the phage-derived enzymes that compromise the bacterial cell envelope may provide valuable information for their application as antimicrobials.
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31
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Abstract
It is commonly thought that each globular protein has a single 3D structure, or fold, that fosters its function. In contrast, recent studies have identified several fold-switching proteins whose secondary structures can be remodeled in response to cellular stimuli. Although thought to be rare, we found 96 literature-validated fold-switching proteins by exhaustively searching the database of protein structures [Protein Data Bank (PDB)]. Characterizing these proteins led us to hypothesize that their abundance may be underrepresented in the PDB. Thus, we developed a computational method that identifies fold-switching proteins and used it to estimate that 0.5–4% of PDB proteins switch folds. These results suggest that proteins switch folds with significant frequency, which has implications for cell biology, genomics, and human health. A central tenet of biology is that globular proteins have a unique 3D structure under physiological conditions. Recent work has challenged this notion by demonstrating that some proteins switch folds, a process that involves remodeling of secondary structure in response to a few mutations (evolved fold switchers) or cellular stimuli (extant fold switchers). To date, extant fold switchers have been viewed as rare byproducts of evolution, but their frequency has been neither quantified nor estimated. By systematically and exhaustively searching the Protein Data Bank (PDB), we found ∼100 extant fold-switching proteins. Furthermore, we gathered multiple lines of evidence suggesting that these proteins are widespread in nature. Based on these lines of evidence, we hypothesized that the frequency of extant fold-switching proteins may be underrepresented by the structures in the PDB. Thus, we sought to identify other putative extant fold switchers with only one solved conformation. To do this, we identified two characteristic features of our ∼100 extant fold-switching proteins, incorrect secondary structure predictions and likely independent folding cooperativity, and searched the PDB for other proteins with similar features. Reassuringly, this method identified dozens of other proteins in the literature with indication of a structural change but only one solved conformation in the PDB. Thus, we used it to estimate that 0.5–4% of PDB proteins switch folds. These results demonstrate that extant fold-switching proteins are likely more common than the PDB reflects, which has implications for cell biology, genomics, and human health.
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32
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Babu K, Arulandu A, Sankaran K. The structure of DLP12 endolysin exhibiting alternate loop conformation and comparative analysis with other endolysins. Proteins 2017; 86:210-217. [PMID: 29179254 DOI: 10.1002/prot.25428] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 11/09/2017] [Accepted: 11/16/2017] [Indexed: 11/08/2022]
Abstract
The lytic enzyme, endolysin, is encoded by bacteriophages (phages) to destroy the peptidoglycan layer of host bacterial cells. The release of phage progenies to start the new infection cycle is dependent on the cell lysis event. Endolysin encoded by DLP12 cryptic prophage is a SAR endolysin which is retained by the bacterium presumably due to the benefit it confers. The structure of DLP12 endolysin (Id: 4ZPU) determined at 2.4 Å resolution is presented here. The DLP12 endolysin structure shows a modular nature and is organized into distinct structural regions. One of the monomers has the loops at the active site in a different conformation. This has led to a suggestion of depicting possibly active and inactive state of DLP12 endolysin. Comparison of DLP12 endolysin structure and sequence with those of related endolysins shows the core three-dimensional fold is similar and the catalytic triad geometry is highly conserved despite the sequence differences. Features essential for T4 lysozyme structure and function such as the distance between catalytic groups, salt bridge and presence of nucleophilic water are conserved in DLP12 endolysin and other endolysins analyzed.
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Affiliation(s)
- Kesavan Babu
- School of Biotechnology, Madurai Kamaraj University, Madurai, 625021, India
| | - Arockiasamy Arulandu
- Membrane Protein Biology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Krishnaswamy Sankaran
- Computational Biology Group, Institute of Mathematical Sciences, Chennai, 600113, India
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33
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Alleyne T, Ignacio DN, Sampson VB, Ashe D, Wilson M. Simulating the slow to fast switch in cytochrome c oxidase catalysis by introducing a loop flip near the enzyme's cytochrome c (substrate) binding site. Biotechnol Appl Biochem 2017; 64:677-685. [PMID: 27489224 DOI: 10.1002/bab.1526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/30/2016] [Indexed: 01/03/2023]
Affiliation(s)
- Trevor Alleyne
- Biochemistry Unit, Faculty of Medical Sciences, The University of the West Indies, St. Augustine Campus, Trinidad and Tobago
| | - Diane N Ignacio
- Biochemistry Unit, Faculty of Medical Sciences, The University of the West Indies, St. Augustine Campus, Trinidad and Tobago
| | - Valerie B Sampson
- Nemours Center for Cancer and Blood Disorders, Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Damian Ashe
- Biochemistry Unit, Faculty of Medical Sciences, The University of the West Indies, St. Augustine Campus, Trinidad and Tobago
| | - Michael Wilson
- School of Biological Sciences, University of Essex, Colchester, Essex, UK
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34
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Biodegradable and Biocompatible Systems Based on Hydroxyapatite Nanoparticles. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app7010060] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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35
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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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36
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Fernandes S, São-José C. More than a hole: the holin lethal function may be required to fully sensitize bacteria to the lytic action of canonical endolysins. Mol Microbiol 2016; 102:92-106. [DOI: 10.1111/mmi.13448] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2016] [Indexed: 12/19/2022]
Affiliation(s)
- Sofia Fernandes
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy; Universidade de Lisboa, Av. Prof. Gama Pinto; Lisboa 1649-003 Portugal
| | - Carlos São-José
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy; Universidade de Lisboa, Av. Prof. Gama Pinto; Lisboa 1649-003 Portugal
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37
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Drulis-Kawa Z, Majkowska-Skrobek G, Maciejewska B. Bacteriophages and phage-derived proteins--application approaches. Curr Med Chem 2016; 22:1757-73. [PMID: 25666799 PMCID: PMC4468916 DOI: 10.2174/0929867322666150209152851] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 11/29/2014] [Accepted: 02/02/2015] [Indexed: 12/17/2022]
Abstract
Currently, the bacterial resistance, especially to most commonly used antibiotics has proved to be a severe therapeutic problem. Nosocomial and community-acquired infections are usually caused by multidrug resistant strains. Therefore, we are forced to develop an alternative or supportive treatment for successful cure of life-threatening infections. The idea of using natural bacterial pathogens such as bacteriophages is already well known. Many papers have been published proving the high antibacterial efficacy of lytic phages tested in animal models as well as in the clinic. Researchers have also investigated the application of non-lytic phages and temperate phages, with promising results. Moreover, the development of molecular biology and novel generation methods of sequencing has opened up new possibilities in the design of engineered phages and recombinant phage-derived proteins. Encouraging performances were noted especially for phage enzymes involved in the first step of viral infection responsible for bacterial envelope degradation, named depolymerases. There are at least five major groups of such enzymes – peptidoglycan hydrolases, endosialidases, endorhamnosidases, alginate lyases and hyaluronate lyases – that have application potential. There is also much interest in proteins encoded by lysis cassette genes (holins, endolysins, spanins) responsible for progeny release during the phage lytic cycle. In this review, we discuss several issues of phage and phage-derived protein application approaches in therapy, diagnostics and biotechnology in general.
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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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Khakhum N, Yordpratum U, Boonmee A, Tattawasart U, Rodrigues JLM, Sermswan RW. Identification of the Burkholderia pseudomallei bacteriophage ST79 lysis gene cassette. J Appl Microbiol 2016; 121:364-72. [PMID: 27038077 DOI: 10.1111/jam.13151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 03/18/2016] [Accepted: 03/31/2016] [Indexed: 11/30/2022]
Abstract
AIMS To identify and characterize the lysis gene cassette from the bacteriophage ST79 that lyses Burkholderia pseudomallei. METHODS AND RESULTS Approximately 1·5 kb of ST79 lysis genes were identified from the phage genome data. It was composed of holin, peptidase M15A or endolysin, lysB and lysC. Each gene and its combinations were cloned into Escherichia coli and the lytic effects were measured. Co-expression of holin and peptidase M15A showed the highest lysis activity. Expression of holin, lysB/C or holin-peptidase M15A-lysB/lysC lysed the E. coli membrane, whereas peptidase M15A alone did not. The predicted transmembrane structures of holin and lysB/C indicated that they could be inserted into the bacterial membrane to form pores, affecting cell permeability and causing lysis. CONCLUSION This is the first report of an investigation into the lysis genes of B. pseudomallei's lytic phage using E. coli as a model. SIGNIFICANCE AND IMPACT OF THE STUDY Burkholderia pseudomallei, a Gram-negative bacterium causing an infectious disease, is intrinsically resistant to several antibiotics, and a vaccine is not available. The lysis genes of ST79, the first reported lytic bacteriophage of B. pseudomallei, were characterized. The development of ST79 as an alternative treatment for skin ulceration, for example, or to be used as a gene cloning tool for B. pseudomallei may be possible with this knowledge.
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Affiliation(s)
- N Khakhum
- Melioidosis Research Center, Khon Kaen University, Khon Kaen, Thailand.,Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - U Yordpratum
- Melioidosis Research Center, Khon Kaen University, Khon Kaen, Thailand.,Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - A Boonmee
- Melioidosis Research Center, Khon Kaen University, Khon Kaen, Thailand.,Department of Microbiology, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - U Tattawasart
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - J L M Rodrigues
- Department of Land, Air and Water Resources, University of California - Davis, Davis, CA, USA
| | - R W Sermswan
- Melioidosis Research Center, Khon Kaen University, Khon Kaen, Thailand.,Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
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Wang Y, Hao H, Zhang S. Lysozyme loading and release from Se doped hydroxyapatite nanoparticles. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 61:545-52. [DOI: 10.1016/j.msec.2015.12.060] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Revised: 11/14/2015] [Accepted: 12/28/2015] [Indexed: 12/15/2022]
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Dunne M, Leicht S, Krichel B, Mertens HDT, Thompson A, Krijgsveld J, Svergun DI, Gómez-Torres N, Garde S, Uetrecht C, Narbad A, Mayer MJ, Meijers R. Crystal Structure of the CTP1L Endolysin Reveals How Its Activity Is Regulated by a Secondary Translation Product. J Biol Chem 2016; 291:4882-93. [PMID: 26683375 PMCID: PMC4777826 DOI: 10.1074/jbc.m115.671172] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 12/16/2015] [Indexed: 11/18/2022] Open
Abstract
Bacteriophages produce endolysins, which lyse the bacterial host cell to release newly produced virions. The timing of lysis is regulated and is thought to involve the activation of a molecular switch. We present a crystal structure of the activated endolysin CTP1L that targets Clostridium tyrobutyricum, consisting of a complex between the full-length protein and an N-terminally truncated C-terminal cell wall binding domain (CBD). The truncated CBD is produced through an internal translation start site within the endolysin gene. Mutants affecting the internal translation site change the oligomeric state of the endolysin and reduce lytic activity. The activity can be modulated by reconstitution of the full-length endolysin-CBD complex with free CBD. The same oligomerization mechanism applies to the CD27L endolysin that targets Clostridium difficile and the CS74L endolysin that targets Clostridium sporogenes. When the CTP1L endolysin gene is introduced into the commensal bacterium Lactococcus lactis, the truncated CBD is also produced, showing that the alternative start codon can be used in other bacterial species. The identification of a translational switch affecting oligomerization presented here has implications for the design of effective endolysins for the treatment of bacterial infections.
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Affiliation(s)
- Matthew Dunne
- From the European Molecular Biology Laboratory, Notkestrasse 85, 22607 Hamburg, Germany
| | - Stefan Leicht
- the European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Boris Krichel
- the Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, 20251 Hamburg, Germany
| | - Haydyn D T Mertens
- From the European Molecular Biology Laboratory, Notkestrasse 85, 22607 Hamburg, Germany
| | - Andrew Thompson
- the Synchrotron Soleil, L'Orme des Merisiers, BP 48, Saint Aubin, 91192 Gif sur Yvette, France
| | - Jeroen Krijgsveld
- the European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Dmitri I Svergun
- From the European Molecular Biology Laboratory, Notkestrasse 85, 22607 Hamburg, Germany
| | - Natalia Gómez-Torres
- the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Departamento de Tecnología de Alimentos, Carretera de La Coruña km 7, 28040 Madrid, Spain
| | - Sonia Garde
- the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Departamento de Tecnología de Alimentos, Carretera de La Coruña km 7, 28040 Madrid, Spain
| | - Charlotte Uetrecht
- the Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Martinistrasse 52, 20251 Hamburg, Germany, the European XFEL GmbH, Notkestrasse 85, 22607 Hamburg, Germany, and
| | - Arjan Narbad
- the Institute of Food Research, Colney, Norwich NR4 7UA, United Kingdom
| | - Melinda J Mayer
- the Institute of Food Research, Colney, Norwich NR4 7UA, United Kingdom
| | - Rob Meijers
- From the European Molecular Biology Laboratory, Notkestrasse 85, 22607 Hamburg, Germany,
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41
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Roces C, Campelo AB, Escobedo S, Wegmann U, García P, Rodríguez A, Martínez B. Reduced Binding of the Endolysin LysTP712 to Lactococcus lactis ΔftsH Contributes to Phage Resistance. Front Microbiol 2016; 7:138. [PMID: 26904011 PMCID: PMC4749879 DOI: 10.3389/fmicb.2016.00138] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 01/25/2016] [Indexed: 02/01/2023] Open
Abstract
Absence of the membrane protease FtsH in Lactococcus lactis hinders release of the bacteriophage TP712. In this work we have analyzed the mechanism responsible for the non-lytic phenotype of L. lactis ΔftsH after phage infection. The lytic cassette of TP712 contains a putative antiholin–pinholin system and a modular endolysin (LysTP712). Inducible expression of the holin gene demonstrated the presence of a dual start motif which is functional in both wildtype and L. lactis ΔftsH cells. Moreover, simulating holin activity with ionophores accelerated lysis of wildtype cells but not L. lactis ΔftsH cells, suggesting inhibition of the endolysin rather than a role of FtsH in holin activation. However, zymograms revealed the synthesis of an active endolysin in both wildtype and L. lactis ΔftsH TP712 lysogens. A reporter protein was generated by fusing the cell wall binding domain of LysTP712 to the fluorescent mCherry protein. Binding of this reporter protein took place at the septa of both wildtype and L. lactis ΔftsH cells as shown by fluorescence microscopy. Nonetheless, fluorescence spectroscopy demonstrated that mutant cells bound 40% less protein. In conclusion, the non-lytic phenotype of L. lactis ΔftsH is not due to direct action of the FtsH protease on the phage lytic proteins but rather to a putative function of FtsH in modulating the architecture of the L. lactis cell envelope that results in a lower affinity of the phage endolysin to its substrate.
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Affiliation(s)
- Clara Roces
- DairySafe Group, Department of Technology and Biotechnology of Dairy Products, Instituto de Productos Lácteos de Asturias - Consejo Superior de Investigaciones Científicas Villaviciosa, Spain
| | - Ana B Campelo
- DairySafe Group, Department of Technology and Biotechnology of Dairy Products, Instituto de Productos Lácteos de Asturias - Consejo Superior de Investigaciones Científicas Villaviciosa, Spain
| | - Susana Escobedo
- DairySafe Group, Department of Technology and Biotechnology of Dairy Products, Instituto de Productos Lácteos de Asturias - Consejo Superior de Investigaciones Científicas Villaviciosa, Spain
| | - Udo Wegmann
- Institute of Food Research, Norwich Research Park Norwich, UK
| | - Pilar García
- DairySafe Group, Department of Technology and Biotechnology of Dairy Products, Instituto de Productos Lácteos de Asturias - Consejo Superior de Investigaciones Científicas Villaviciosa, Spain
| | - Ana Rodríguez
- DairySafe Group, Department of Technology and Biotechnology of Dairy Products, Instituto de Productos Lácteos de Asturias - Consejo Superior de Investigaciones Científicas Villaviciosa, Spain
| | - Beatriz Martínez
- DairySafe Group, Department of Technology and Biotechnology of Dairy Products, Instituto de Productos Lácteos de Asturias - Consejo Superior de Investigaciones Científicas Villaviciosa, Spain
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Abstract
We have been witnessing an increased interest in bacteriophage studies focused on their use as antibacterial agents to fight pathogenic bacteria. This interest is a consequence of the phages' ability to lyse a bacterial host. Until recently, little was known about the mechanisms used by mycobacteriophages to induce lysis of their complex hosts. However, studies on Ms6-induced lysis have changed this scenario and provided new insights into the mechanisms of bacteriophage-induced lysis. Specific lysis protein genes have been identified in mycobacteriophage genomes, reflecting the particular mycobacterial cell envelope composition. These include enzymes that target mycolic acid-containing lipids and proteins that participate in the secretion of the phage endolysin, functioning as chaperone-like proteins. This chapter focuses on the current knowledge of mycobacteriophage-induced lysis, starting with an overview of phage lysis and basic features of the lysis players.
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Pohane AA, Jain V. Insights into the regulation of bacteriophage endolysin: multiple means to the same end. Microbiology (Reading) 2015; 161:2269-76. [DOI: 10.1099/mic.0.000190] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Kamilla S, Jain V. Mycobacteriophage D29 holin C-terminal region functionally assists in holin aggregation and bacterial cell death. FEBS J 2015; 283:173-90. [PMID: 26471254 DOI: 10.1111/febs.13565] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 10/11/2015] [Accepted: 10/13/2015] [Indexed: 01/09/2023]
Abstract
Holins are phage-encoded small transmembrane proteins that perforate the bacterial cytoplasmic membrane. In most cases, this process allows the phage-encoded peptidoglycan hydrolases to act on the cell wall, resulting in host cell lysis and phage release. We report a detailed functional characterization of Mycobacterium phage D29 gp11 coding for a putative holin that, upon expression, rapidly kills both Escherichia coli and Mycobacterium smegmatis. We dissected Gp11 by making several deletions and expressing them in E. coli. The shortening of Gp11 from its C-terminus results in diminished cytotoxicity and smaller holes. Evidently, the two transmembrane domains (TMDs) present at the N-terminus of Gp11 are incapable of integrating into the cytoplasmic membrane and do not show toxicity. Interestingly, the fusion of two TMDs and a small C-terminal region that bears the coiled-coil motif resulted in restoration of the cell killing ability of the protein. We further show that the second TMD is dispensable in protein toxicity because its deletion does not abolish Gp11-mediated cell death. We conclude that Gp11 C-terminal region is necessary but not sufficient for toxicity. These results shed light on a yet undiscovered role of Gp11 C-terminal region that will help clarify the mechanism of holin-mediated membrane perforation. Finally, we abolish the toxicity of Gp11 using a specific Gly to Asp substitution in the putative loop region of the protein; the mutant protein may help to clarify how holin functions in mycobacteriophage D29.
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Affiliation(s)
- Soumya Kamilla
- Microbiology and Molecular Biology Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, India
| | - Vikas Jain
- Microbiology and Molecular Biology Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, India
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45
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Production and characterization of neurosecretory protein GM using Escherichia coli and Chinese Hamster Ovary cells. FEBS Open Bio 2015; 5:844-51. [PMID: 26587371 PMCID: PMC4625114 DOI: 10.1016/j.fob.2015.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 10/06/2015] [Accepted: 10/09/2015] [Indexed: 02/06/2023] Open
Abstract
A novel gene, neurosecretory protein GM (NPGM) was recently discovered in birds and mammals. Endogenous mature protein encoded by NPGM has not yet been identified. We produced and characterized the mature form of rat NPGM using E. coli and CHO cells. A specific antibody against rat NPGM was raised. NPGM is a small secretory protein which has a disulfide bond and a free Cys residue.
Neurosecretory protein GL (NPGL) and neurosecretory protein GM (NPGM) are paralogs recently discovered in birds and in mammals. The post-translational products of NPGL and of NPGM genes include a signal peptide sequence, a glycine amidation signal, and a dibasic amino acid cleavage site. This suggests that the mature forms of NPGL and of NPGM are small proteins secreted in the hypothalamus and containing an amidated C-terminus. However, endogenous NPGL and NPGM have not yet been identified. Chicken NPGL and NPGM have two highly conserved Cys residues that are likely to form a disulfide bond, while mammalian NPGM has one additional Cys residue located between the two conserved Cys residues and the correct disulfide bond pattern is unclear. In this study, we prepared rat NPGM to elucidate the structure of its mature form. We first expressed the predicted mature NPGM, containing an extra C-terminal Gly, in Escherichia coli SHuffle cells, which are engineered to promote the formation of native disulfide bridges in recombinant proteins. We observed the presence of a disulfide bond between the N-terminal Cys residue and the second Cys residue, while the C-terminal Cys residue was free. Secondly, we transfected a construct containing the entire NPGM open reading frame into Chinese Hamster Ovary cells, and observed that NPGM was cleaved immediately after the signal peptide and that it was secreted into the medium. Furthermore, the protein presented a disulfide bond at the same location observed in recombinant NPGM.
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46
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Chatelle C, Kraemer S, Ren G, Chmura H, Marechal N, Boyd D, Roggemans C, Ke N, Riggs P, Bardwell J, Berkmen M. Converting a Sulfenic Acid Reductase into a Disulfide Bond Isomerase. Antioxid Redox Signal 2015; 23:945-57. [PMID: 26191605 PMCID: PMC4624244 DOI: 10.1089/ars.2014.6235] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
AIMS Posttranslational formation of disulfide bonds is essential for the folding of many secreted proteins. Formation of disulfide bonds in a protein with more than two cysteines is inherently fraught with error and can result in incorrect disulfide bond pairing and, consequently, misfolded protein. Protein disulfide bond isomerases, such as DsbC of Escherichia coli, can recognize mis-oxidized proteins and shuffle the disulfide bonds of the substrate protein into their native folded state. RESULTS We have developed a simple blue/white screen that can detect disulfide bond isomerization in vivo, using a mutant alkaline phosphatase (PhoA*) in E. coli. We utilized this screen to isolate mutants of the sulfenic acid reductase (DsbG) that allowed this protein to act as a disulfide bond isomerase. Characterization of the isolated mutants in vivo and in vitro allowed us to identify key amino acid residues responsible for oxidoreductase properties of thioredoxin-like proteins such as DsbC or DsbG. INNOVATION AND CONCLUSIONS Using these key residues, we also identified and characterized interesting environmental homologs of DsbG with novel properties, thus demonstrating the capacity of this screen to discover and elucidate mechanistic details of in vivo disulfide bond isomerization.
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Affiliation(s)
- Claire Chatelle
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts
| | - Stéphanie Kraemer
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts.,2 Actelion, Allschwil, Switzerland
| | - Guoping Ren
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts
| | - Hannah Chmura
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts
| | - Nils Marechal
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts
| | - Dana Boyd
- 3 Department of Microbiology and Immunobiology, Harvard Medical School , Boston, Massachusetts
| | - Caroline Roggemans
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts.,4 Novartis, Basel, Switzerland
| | - Na Ke
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts
| | - Paul Riggs
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts
| | - James Bardwell
- 5 Howard Hughes Medical Institute Molecular, Cellular and Developmental Biology, University of Michigan , Ann Arbor, Michigan
| | - Mehmet Berkmen
- 1 Protein Expression and Modification, New England Biolabs, Ipswich, Massachusetts
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Porter LL, He Y, Chen Y, Orban J, Bryan PN. Subdomain interactions foster the design of two protein pairs with ∼80% sequence identity but different folds. Biophys J 2015; 108:154-62. [PMID: 25564862 DOI: 10.1016/j.bpj.2014.10.073] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 10/28/2014] [Accepted: 10/30/2014] [Indexed: 01/26/2023] Open
Abstract
Metamorphic proteins, including proteins with high levels of sequence identity but different folds, are exceptions to the long-standing rule-of-thumb that proteins with as little as 30% sequence identity adopt the same fold. Which topologies can be bridged by these highly identical sequences remains an open question. Here we bridge two 3-α-helix bundle proteins with two radically different folds. Using a straightforward approach, we engineered the sequences of one subdomain within maltose binding protein (MBP, α/β/α-sandwich) and another within outer surface protein A (OspA, β-sheet) to have high sequence identity (80 and 77%, respectively) with engineered variants of protein G (GA, 3-α-helix bundle). Circular dichroism and nuclear magnetic resonance spectra of all engineered variants demonstrate that they maintain their native conformations despite substantial sequence modification. Furthermore, the MBP variant (80% identical to GA) remained active. Thermodynamic analysis of numerous GA and MBP variants suggests that the key to our approach involved stabilizing the modified MBP and OspA subdomains via external interactions with neighboring substructures, indicating that subdomain interactions can stabilize alternative folds over a broad range of sequence variation. These findings suggest that it is possible to bridge one fold with many other topologies, which has implications for protein folding, evolution, and misfolding diseases.
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Affiliation(s)
- Lauren L Porter
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland; Potomac Affinity Proteins, Rockville, Maryland.
| | - Yanan He
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland
| | - Yihong Chen
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland
| | - John Orban
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland; Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland
| | - Philip N Bryan
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland; Potomac Affinity Proteins, Rockville, Maryland
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Zheng H, Mandal A, Shumilin IA, Chordia MD, Panneerdoss S, Herr JC, Minor W. Sperm Lysozyme-Like Protein 1 (SLLP1), an intra-acrosomal oolemmal-binding sperm protein, reveals filamentous organization in protein crystal form. Andrology 2015; 3:756-71. [PMID: 26198801 PMCID: PMC5040164 DOI: 10.1111/andr.12057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/29/2015] [Accepted: 04/30/2015] [Indexed: 01/07/2023]
Abstract
Sperm lysozyme-like protein 1 (SLLP1) is one of the lysozyme-like proteins predominantly expressed in mammalian testes that lacks bacteriolytic activity, localizes in the sperm acrosome, and exhibits high affinity for an oolemmal receptor, SAS1B. The crystal structure of mouse SLLP1 (mSLLP1) was determined at 2.15 Å resolution. mSLLP1 monomer adopts a structural fold similar to that of chicken/mouse lysozymes retaining all four canonical disulfide bonds. mSLLP1 is distinct from c-lysozyme by substituting two essential catalytic residues (E35T/D52N), exhibiting different surface charge distribution, and by forming helical filaments approximately 75 Å in diameter with a 25 Å central pore comprised of six monomers per helix turn repeating every 33 Å. Cross-species alignment of all reported SLLP1 sequences revealed a set of invariant surface regions comprising a characteristic fingerprint uniquely identifying SLLP1 from other c-lysozyme family members. The fingerprint surface regions reside around the lips of the putative glycan-binding groove including three polar residues (Y33/E46/H113). A flexible salt bridge (E46-R61) was observed covering the glycan-binding groove. The conservation of these regions may be linked to their involvement in oolemmal protein binding. Interaction between SLLP1 monomer and its oolemmal receptor SAS1B was modeled using protein-protein docking algorithms, utilizing the SLLP1 fingerprint regions along with the SAS1B conserved surface regions. This computational model revealed complementarity between the conserved SLLP1/SAS1B interacting surfaces supporting the experimentally observed SLLP1/SAS1B interaction involved in fertilization.
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Affiliation(s)
- Heping Zheng
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908, USA
| | - Arabinda Mandal
- Department of Cell Biology, Center for Research in Contraceptive and Reproductive Health, University of Virginia, Charlottesville, VA 22908, USA
| | - Igor A. Shumilin
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908, USA
| | - Mahendra D. Chordia
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908, USA
| | - Subbarayalu Panneerdoss
- Department of Cell Biology, Center for Research in Contraceptive and Reproductive Health, University of Virginia, Charlottesville, VA 22908, USA
| | - John C. Herr
- Department of Cell Biology, Center for Research in Contraceptive and Reproductive Health, University of Virginia, Charlottesville, VA 22908, USA
- Correspondence: Wladek Minor, Ph.D., Department of Molecular Physiology and Biological Physics, University of Virginia, P.O. Box 800736, Charlottesville, Virginia 22908-0736, USA. Ph: +1 434 243-6865; Fax: +1 434 982-1616; , John C. Herr, Ph.D., Department of Cell Biology, University of Virginia, P.O. Box 800732, Charlottesville, Virginia 22908, USA. Ph: +1 434 924-2007; Fax: +1 434 982-3912;
| | - Wladek Minor
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22908, USA
- Correspondence: Wladek Minor, Ph.D., Department of Molecular Physiology and Biological Physics, University of Virginia, P.O. Box 800736, Charlottesville, Virginia 22908-0736, USA. Ph: +1 434 243-6865; Fax: +1 434 982-1616; , John C. Herr, Ph.D., Department of Cell Biology, University of Virginia, P.O. Box 800732, Charlottesville, Virginia 22908, USA. Ph: +1 434 924-2007; Fax: +1 434 982-3912;
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Guo T, Zhang C, Liu W, Wang S, Kong J. Functional analysis of the N-terminal region of endolysin Lyb5 encoded by Lactobacillus fermentum bacteriophage φPYB5. Int J Food Microbiol 2015; 203:1-7. [PMID: 25770427 DOI: 10.1016/j.ijfoodmicro.2015.02.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 02/04/2015] [Accepted: 02/26/2015] [Indexed: 12/12/2022]
Abstract
Lactobacillus fermentum temperate bacteriophage φPYB5 uses endolysin Lyb5 and holin Hyb5 to burst the host cell. Previous results showed that expression of Lyb5 in Escherichia coli caused host cell lysis slowly, leading us to suppose that Lyb5 could pass the cytoplasmic membrane partly. In this work, the function of a putative signal peptide (SPLyb5) at the N-terminal of Lyb5 was investigated. In E. coli, the cell adopted a spherical shape during induction of Lyb5 protein, while morphological changes were not observed during expression of the SPLyb5 truncation, indicating that the SPLyb5 motif may serve as a functional signal peptide. However, SPLyb5 was not proteolytically cleaved at the predicted site during the translocation of Lyb5, and the expressed Lyb5 protein appeared in the cytoplasm, cytoplasmic membrane and periplasm fractions with the same molecular mass. Similar results were obtained using Lactococcus lactis as a host to express Lyb5. These results indicated that SPLyb5 could direct Lyb5 to the periplasm in a membrane-tethered form, and then release it as a soluble active enzyme into the periplasm. In addition, SPLyb5 could also drive the fused NucleaseB protein to the extracytoplasm environment in E. coli as well as in L. lactis. We proposed that in Gram-negative and Gram-positive hosts SPLyb5 acted as a signal-anchor-release domain, which was firstly identified here by experimental evidences in lactic acid bacteria phages. The application of signal-anchor-release domain for endolysin export in bacteriophages infecting Gram-positive and Gram-negative hosts was discussed.
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Affiliation(s)
- Tingting Guo
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China; School of Environmental Science and Engineering, Shandong University, Jinan 250100, PR China
| | - Chenchen Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China
| | - Wei Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China
| | - Shaohua Wang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China
| | - Jian Kong
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China.
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50
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Götz F, Yu W, Dube L, Prax M, Ebner P. Excretion of cytosolic proteins (ECP) in bacteria. Int J Med Microbiol 2014; 305:230-7. [PMID: 25596889 DOI: 10.1016/j.ijmm.2014.12.021] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Excretion of cytosolic proteins (ECP) has been reported in bacteria and eukaryotes. As none of the classical signal peptide (SP) dependent or SP-independent pathways could be associated with ECP, it has been also referred to as 'non-classical protein export'. When microbiologists first began to study this subject in 1990, mainly singular cytoplasmic proteins were investigated, such as GAPDH at the cell surface and in the supernatant of pathogenic streptococci or glutamine synthetase (GlnA) as a major extracellular protein in pathogenic mycobacteria. Later, with the rising popularity of proteomics, it became obvious that the secretome of most bacteria contained a copious amount of cytosolic proteins. In particular ancient proteins such as glycolytic enzymes, chaperones, translation factors or enzymes involved in detoxification of reactive oxygen were found in the supernatants. As the excreted proteins do not possess a common motive, the most widespread opinion is that ECP is due to cell lysis. Indeed, upregulation of autolysins or distortion of the murein structure increased ECP, suggesting that enhanced ECP is some sort of survival strategy to counteract osmotic stress. However, in the meantime there are mounting evidences and hints that speak against cell lysis as a primary mechanism for ECP. Very likely, ECP belongs to the normal life cycle of bacteria and involves a programmed process. This review provides a brief overview of the 'non-classical protein export'.
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Affiliation(s)
- Friedrich Götz
- Microbial Genetics, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, 72076 Tübingen, Germany.
| | - Wenqi Yu
- Microbial Genetics, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, 72076 Tübingen, Germany
| | - Linda Dube
- Microbial Genetics, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, 72076 Tübingen, Germany
| | - Marcel Prax
- Microbial Genetics, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, 72076 Tübingen, Germany
| | - Patrick Ebner
- Microbial Genetics, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, 72076 Tübingen, Germany
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