1
|
Mondal A, Teimouri H, Kolomeisky AB. Molecular mechanisms of precise timing in cell lysis. Biophys J 2024; 123:3090-3099. [PMID: 38971973 DOI: 10.1016/j.bpj.2024.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/03/2024] [Accepted: 07/02/2024] [Indexed: 07/08/2024] Open
Abstract
Many biological systems exhibit precise timing of events, and one of the most known examples is cell lysis, which is a process of breaking bacterial host cells in the virus infection cycle. However, the underlying microscopic picture of precise timing remains not well understood. We present a novel theoretical approach to explain the molecular mechanisms of effectively deterministic dynamics in biological systems. Our hypothesis is based on the idea of stochastic coupling between relevant underlying biophysical and biochemical processes that lead to noise cancellation. To test this hypothesis, we introduced a minimal discrete-state stochastic model to investigate how holin proteins produced by bacteriophages break the inner membranes of gram-negative bacteria. By explicitly solving this model, the dynamic properties of cell lysis are fully evaluated, and theoretical predictions quantitatively agree with available experimental data for both wild-type and holin mutants. It is found that the observed threshold-like behavior is a result of the balance between holin proteins entering the membrane and leaving the membrane during the lysis. Theoretical analysis suggests that the cell lysis achieves precise timing for wild-type species by maximizing the number of holins in the membrane and narrowing their spatial distribution. In contrast, for mutated species, these conditions are not satisfied. Our theoretical approach presents a possible molecular picture of precise dynamic regulation in intrinsically random biological processes.
Collapse
Affiliation(s)
- Anupam Mondal
- Center for Theoretical Biological Physics, Rice University, Houston, Texas; Department of Chemistry, Rice University, Houston, Texas
| | - Hamid Teimouri
- Center for Theoretical Biological Physics, Rice University, Houston, Texas; Department of Chemistry, Rice University, Houston, Texas
| | - Anatoly B Kolomeisky
- Center for Theoretical Biological Physics, Rice University, Houston, Texas; Department of Chemistry, Rice University, Houston, Texas; Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas.
| |
Collapse
|
2
|
Mondal A, Teimouri H, Kolomeisky AB. Elucidating Physicochemical Features of Holin Proteins Responsible for Bacterial Cell Lysis. J Phys Chem B 2024; 128:7129-7140. [PMID: 38985954 DOI: 10.1021/acs.jpcb.4c03040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
Bacterial resistance to conventional antibiotics stimulated the development of so-called "phage therapies" that rely on cell lysis, which is a process of destroying bacterial cells due to their infections by bacterial viruses. For λ bacteriophages, it is known that the critical role in this process is played by holin proteins that aggregate in cellular membranes before breaking them apart. While multiple experimental studies probed various aspects of cell lysis, the underlying molecular mechanisms remain not well understood. Here we investigate what physicochemical properties of holin proteins are the most relevant for these processes by employing statistical correlation analysis of cell lysis dynamics for different experimentally observed mutant species. Our findings reveal significant correlations between various physicochemical features and cell lysis dynamics. Notably, we uncover a strong inverse correlation between local hydrophobicity and cell lysis times, underscoring the crucial role of hydrophobic interactions in membrane disruption. Stimulated by these observations, a predictive model capable of explicitly estimating cell lysis times for any holin protein mutants based on their mean hydrophobicity values is developed. Our study not only provides important microscopic insights into cell lysis phenomena but also proposes specific routes to optimize medical and biotechnological applications of bacteriophages.
Collapse
Affiliation(s)
- Anupam Mondal
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Hamid Teimouri
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Anatoly B Kolomeisky
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
| |
Collapse
|
3
|
Cahill J, Holt A, Theodore M, Moreland R, O'Leary C, Martin C, Bettridge K, Xiao J, Young R. Spatial and temporal control of lysis by the lambda holin. mBio 2024; 15:e0129023. [PMID: 38126784 PMCID: PMC10865782 DOI: 10.1128/mbio.01290-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 11/13/2023] [Indexed: 12/23/2023] Open
Abstract
The infection cycle of phage λ terminates in lysis mediated by three types of lysis proteins, each disrupting a layer in the bacterial envelope: the S105 holin, the R endolysin, and the Rz/Rz1 spanin complex targeting the inner membrane, cell wall or peptidoglycan, and the outer membrane, respectively. Video microscopy has shown that in most infections, lysis occurs as a sudden, explosive event at a cell pole, such that the initial product is a less refractile ghost that retains rod-shaped morphology. Here, we investigate the molecular basis of polar lysis using time-lapse fluorescence microscopy. The results indicate that the holin determines the morphology of lysis by suddenly forming two-dimensional rafts at the poles about 100 s prior to lysis. Given the physiological and biochemical similarities between the lambda holin and other class I holins, dynamic redistribution and sudden concentration may be common features of holins, probably reflecting the fitness advantage of all-or-nothing lysis regulation.IMPORTANCEIn this study, we use fluorescent video microscopy to track -green fluorescent protein (GFP)-labeled holin in the minutes prior to phage lysis. Our work contextualizes prior genetic and biochemical data, showing when hole formation starts and where holin oligomers form in relation to the site of lytic rupture. Furthermore, prior work showed that the morphology of lambda-infected cells is characterized by an explosive event starting at the cell pole; however, the basis for this was not clear. This study shows that holin most often oligomerizes at cell poles and that the site of the oligomerization is spatially correlated with the site of lytic blowout. Therefore, the holin is the key contributor to polar lysis morphology for phage lambda.
Collapse
Affiliation(s)
- Jesse Cahill
- Sandia National Labs, Albuquerque, New Mexico, USA
| | - Ashley Holt
- Department of Biochemistry and Biophysics, Center of Phage Technology, Texas A&M University, College Station, Texas, USA
| | - Matthew Theodore
- Department of Biochemistry and Biophysics, Center of Phage Technology, Texas A&M University, College Station, Texas, USA
| | - Russell Moreland
- Department of Biochemistry and Biophysics, Center of Phage Technology, Texas A&M University, College Station, Texas, USA
| | - Chandler O'Leary
- Department of Biochemistry and Biophysics, Center of Phage Technology, Texas A&M University, College Station, Texas, USA
| | - Cody Martin
- Department of Biochemistry and Biophysics, Center of Phage Technology, Texas A&M University, College Station, Texas, USA
| | - Kelsey Bettridge
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jie Xiao
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ry Young
- Sandia National Labs, Albuquerque, New Mexico, USA
| |
Collapse
|
4
|
Samir S. Molecular Machinery of the Triad Holin, Endolysin, and Spanin: Key Players Orchestrating Bacteriophage-Induced Cell Lysis and their Therapeutic Applications. Protein Pept Lett 2024; 31:85-96. [PMID: 38258777 DOI: 10.2174/0109298665181166231212051621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/22/2023] [Accepted: 11/23/2023] [Indexed: 01/24/2024]
Abstract
Phage therapy, a promising alternative to combat multidrug-resistant bacterial infections, harnesses the lytic cycle of bacteriophages to target and eliminate bacteria. Key players in this process are the phage lysis proteins, including holin, endolysin, and spanin, which work synergistically to disrupt the bacterial cell wall and induce lysis. Understanding the structure and function of these proteins is crucial for the development of effective therapies. Recombinant versions of these proteins have been engineered to enhance their stability and efficacy. Recent progress in the field has led to the approval of bacteriophage-based therapeutics as drugs, paving the way for their clinical use. These proteins can be combined in phage cocktails or combined with antibiotics to enhance their activity against bacterial biofilms, a common cause of treatment failure. Animal studies and clinical trials are being conducted to evaluate the safety and efficacy of phage therapy in humans. Overall, phage therapy holds great potential as a valuable tool in the fight against multidrug- resistant bacteria, offering hope for the future of infectious disease treatment.
Collapse
Affiliation(s)
- Safia Samir
- Department of Biochemistry and Molecular Biology, Theodor Bilharz Research Institute, Giza, Egypt
| |
Collapse
|
5
|
Morris AK, Perera RS, Sahu ID, Lorigan GA. Topological examination of the bacteriophage lambda S holin by EPR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184083. [PMID: 36370910 PMCID: PMC9771973 DOI: 10.1016/j.bbamem.2022.184083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 10/26/2022] [Accepted: 10/31/2022] [Indexed: 11/11/2022]
Abstract
The S protein from bacteriophage lambda is a three-helix transmembrane protein produced by the prophage which accumulates in the host membrane during late gene expression. It is responsible for the first step in lysing the host cell at the end of the viral life cycle by multimerizing together to form large pores which permeabilize the host membrane to allow the escape of virions. Several previous studies have established a model for the assembly of holin into functional holes and the manner in which they pack together, but it is still not fully understood how the very rapid transition from monomer or dimer to multimeric pore occurs with such precise timing once the requisite threshold is reached. Here, site-directed spin labeling with a nitroxide label at introduced cysteine residues is used to corroborate existing topological data from a crosslinking study of the multimerized holin by EPR spectroscopy. CW-EPR spectral lineshape analysis and power saturation data are consistent with a three-helix topology with an unstructured C-terminal domain, as well as at least one interface on transmembrane domain 1 which is exposed to the lumen of the hole, and a highly constrained steric environment suggestive of a tight helical packing interface at transmembrane domain 2.
Collapse
Affiliation(s)
- Andrew K Morris
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| | - Rehani S Perera
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| | - Indra D Sahu
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA; Natural Science Division, Campbellsville University, Campbellsville, KY 42718, USA.
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| |
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
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.
Collapse
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
| |
Collapse
|
8
|
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: 10] [Impact Index Per Article: 5.0] [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.
Collapse
|
9
|
Ahammad T, Khan RH, Sahu ID, Drew DL, Faul E, Li T, McCarrick RM, Lorigan GA. Pinholin S 21 mutations induce structural topology and conformational changes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183771. [PMID: 34499883 DOI: 10.1016/j.bbamem.2021.183771] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 08/30/2021] [Accepted: 09/01/2021] [Indexed: 12/23/2022]
Abstract
The bacteriophage infection cycle is terminated at a predefined time to release the progeny virions via a robust lytic system composed of holin, endolysin, and spanin proteins. Holin is the timekeeper of this process. Pinholin S21 is a prototype holin of phage Φ21, which determines the timing of host cell lysis through the coordinated efforts of pinholin and antipinholin. However, mutations in pinholin and antipinholin play a significant role in modulating the timing of lysis depending on adverse or favorable growth conditions. Earlier studies have shown that single point mutations of pinholin S21 alter the cell lysis timing, a proxy for pinholin function as lysis is also dependent on other lytic proteins. In this study, continuous wave electron paramagnetic resonance (CW-EPR) power saturation and double electron-electron resonance (DEER) spectroscopic techniques were used to directly probe the effects of mutations on the structure and conformational changes of pinholin S21 that correlate with pinholin function. DEER and CW-EPR power saturation data clearly demonstrate that increased hydrophilicity induced by residue mutations accelerate the externalization of antipinholin transmembrane domain 1 (TMD1), while increased hydrophobicity prevents the externalization of TMD1. This altered hydrophobicity is potentially accelerating or delaying the activation of pinholin S21. It was also found that mutations can influence intra- or intermolecular interactions in this system, which contribute to the activation of pinholin and modulate the cell lysis timing. This could be a novel approach to analyze the mutational effects on other holin systems, as well as any other membrane protein in which mutation directly leads to structural and conformational changes.
Collapse
Affiliation(s)
- Tanbir Ahammad
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Rasal H Khan
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Indra D Sahu
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA; Natural Science Division, Campbellsville University, Campbellsville, KY 42718, USA
| | - Daniel L Drew
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Emily Faul
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Tianyan Li
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Robert M McCarrick
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| |
Collapse
|
10
|
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: 15] [Impact Index Per Article: 5.0] [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.
Collapse
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.
| |
Collapse
|
11
|
Zhou B, Wu Y, Su Z. Computational Simulation of Holin S105 in Membrane Bilayer and Its Dimerization Through a Helix-Turn-Helix Motif. J Membr Biol 2021; 254:397-407. [PMID: 34189599 PMCID: PMC10811654 DOI: 10.1007/s00232-021-00187-w] [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: 01/03/2021] [Accepted: 05/15/2021] [Indexed: 11/30/2022]
Abstract
During the final step of the bacteriophage infection cycle, the cytoplasmic membrane of host cells is disrupted by small membrane proteins called holins. The function of holins in cell lysis is carried out by forming a highly ordered structure called lethal lesion, in which the accumulation of holins in the cytoplasmic membrane leads to the sudden opening of a hole in the middle of this oligomer. Previous studies showed that dimerization of holins is a necessary step to induce their higher order assembly. However, the molecular mechanism underlying the holin-mediated lesion formation is not well understood. In order to elucidate the functions of holin, we first computationally constructed a structural model for our testing system: the holin S105 from bacteriophage lambda. All atom molecular dynamic simulations were further applied to refine its structure and study its dynamics as well as interaction in lipid bilayer. Additional simulations on association between two holins provide supportive evidence to the argument that the C-terminal region of holin plays a critical role in regulating the dimerization. In detail, we found that the adhesion of specific nonpolar residues in transmembrane domain 3 (TMD3) in a polar environment serves as the driven force of dimerization. Our study therefore brings insights to the design of binding interfaces between holins, which can be potentially used to modulate the dynamics of lesion formation.
Collapse
Affiliation(s)
- Brian Zhou
- Edgemont Jr.\Sr. High School, 200 White Oak Ln, Scarsdale, NY, 10583, USA
| | - Yinghao Wu
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Zhaoqian Su
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10461, USA.
| |
Collapse
|
12
|
Aslam B, Arshad MI, Aslam MA, Muzammil S, Siddique AB, Yasmeen N, Khurshid M, Rasool M, Ahmad M, Rasool MH, Fahim M, Hussain R, Xia X, Baloch Z. Bacteriophage Proteome: Insights and Potentials of an Alternate to Antibiotics. Infect Dis Ther 2021; 10:1171-1193. [PMID: 34170506 PMCID: PMC8322358 DOI: 10.1007/s40121-021-00446-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 03/27/2021] [Indexed: 01/21/2023] Open
Abstract
Introduction The mounting incidence of multidrug-resistant bacterial strains and the dearth of novel antibiotics demand alternate therapies to manage the infections caused by resistant superbugs. Bacteriophages and phage=derived proteins are considered as potential alternates to treat such infections, and have several applications in health care systems. The aim of this review is to explore the hidden potential of bacteriophage proteins which may be a practical alternative approach to manage the threat of antibiotic resistance. Results Clinical trials are in progress for the use of phage therapy as a tool for routine medical use; however, the existing regulations may hamper their development of routine antimicrobial agents. The advancement of molecular techniques and the advent of sequencing have opened new potentials for the design of engineered bacteriophages as well as recombinant bacteriophage proteins. The phage enzymes and proteins encoded by the lysis cassette genes, especially endolysins, holins, and spanins, have shown plausible potentials as therapeutic candidates. Conclusion This review offers an integrated viewpoint that aims to decipher the insights and abilities of bacteriophages and their derived proteins as potential alternatives to antibiotics.
Collapse
Affiliation(s)
- Bilal Aslam
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Muhammad Imran Arshad
- Institute of Microbiology, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Muhammad Aamir Aslam
- Institute of Microbiology, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Saima Muzammil
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Abu Baker Siddique
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Nafeesa Yasmeen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, P.R. China
| | - Mohsin Khurshid
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Maria Rasool
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Moeed Ahmad
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | | | - Mohammad Fahim
- College of Life Sciences, Lanzhou University, Lanzhou, China
| | - Riaz Hussain
- University College of Veterinary and Animal Sciences, Islamia University Bahawalpur, Bahawalpur, Pakistan
| | - Xueshan Xia
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, P.R. China.
| | - Zulqarnain Baloch
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, P.R. China.
| |
Collapse
|
13
|
The Novel Halovirus Hardycor1, and the Presence of Active (Induced) Proviruses in Four Haloarchaea. Genes (Basel) 2021; 12:genes12020149. [PMID: 33498646 PMCID: PMC7911831 DOI: 10.3390/genes12020149] [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: 12/23/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 12/15/2022] Open
Abstract
The virus Hardycor1 was isolated in 1998 and infects the haloarchaeon Halorubrum coriense. DNA from a frozen stock (HC1) was sequenced and the viral genome found to be 45,142 bp of dsDNA, probably having redundant, circularly permuted termini. The genome showed little similarity (BLASTn) to known viruses. Only twenty-two of the 53 (41%) predicted proteins were significantly similar to sequences in the NCBI nr protein database (E-value ≤ 10-15). Six caudovirus-like proteins were encoded, including large subunit terminase (TerL), major capsid protein (Mcp) and tape measure protein (Tmp). Hardycor1 was predicted to be a siphovirus (VIRFAM). No close relationship to other viruses was found using phylogenetic tree reconstructions based on TerL and Mcp. Unexpectedly, the sequenced virus stock HC1 also revealed two induced proviruses of the host: a siphovirus (Humcor1) and a pleolipovirus (Humcor2). A re-examination of other similarly sequenced, archival virus stocks revealed induced proviruses of Haloferax volcanii, Haloferax gibbonsii and Haloarcula hispanica, three of which were pleolipoviruses. One provirus (Halfvol2) of Hfx. volcanii showed little similarity (BLASTn) to known viruses and probably represents a novel virus group. The attP sequences of many pleolipoproviruses were found to be embedded in a newly detected coding sequence, split in the provirus state, that spans between genes for integrase and a downstream CxxC-motif protein. This gene might play an important role in regulation of the temperate state.
Collapse
|
14
|
Ahammad T, Drew DL, Sahu ID, Khan RH, Butcher BJ, Serafin RA, Galende AP, McCarrick RM, Lorigan GA. Conformational Differences Are Observed for the Active and Inactive Forms of Pinholin S 21 Using DEER Spectroscopy. J Phys Chem B 2020; 124:11396-11405. [PMID: 33289567 DOI: 10.1021/acs.jpcb.0c09081] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Bacteriophages have evolved with an efficient host cell lysis mechanism to terminate the infection cycle and release the new progeny virions at the optimum time, allowing adaptation with the changing host and environment. Among the lytic proteins, holin controls the first and rate-limiting step of host cell lysis by permeabilizing the inner membrane at an allele-specific time known as "holin triggering". Pinholin S21 is a prototype holin of phage Φ21 which makes many nanoscale holes and destroys the proton motive force, which in turn activates the signal anchor release (SAR) endolysin system to degrade the peptidoglycan layer of the host cell and destruction of the outer membrane by the spanin complex. Like many others, phage Φ21 has two holin proteins: active pinholin and antipinholin. The antipinholin form differs only by three extra amino acids at the N-terminus; however, it has a different structural topology and conformation with respect to the membrane. Predefined combinations of active pinholin and antipinholin fine-tune the lysis timing through structural dynamics and conformational changes. Previously, the dynamics and topology of active pinholin and antipinholin were investigated (Ahammad et al. JPCB 2019, 2020) using continuous wave electron paramagnetic resonance (CW-EPR) spectroscopy. However, detailed structural studies and direct comparison of these two forms of pinholin S21 are absent in the literature. In this study, the structural topology and conformations of active pinholin (S2168) and inactive antipinholin (S2168IRS) in DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) proteoliposomes were investigated using the four-pulse double electron-electron resonance (DEER) EPR spectroscopic technique to measure distances between transmembrane domains 1 and 2 (TMD1 and TMD2). Five sets of interlabel distances were measured via DEER spectroscopy for both the active and inactive forms of pinholin S21. Structural models of the active pinholin and inactive antipinholin forms in DMPC proteoliposomes were obtained using the experimental DEER distances coupled with the simulated annealing software package Xplor-NIH. TMD2 of S2168 remains in the lipid bilayer, and TMD1 is partially externalized from the bilayer with some residues located on the surface. However, both TMDs remain incorporated in the lipid bilayer for the inactive S2168IRS form. This study demonstrates, for the first time, clear structural topology and conformational differences between the two forms of pinholin S21. This work will pave the way for further studies of other holin systems using the DEER spectroscopic technique and will give structural insight into these biological clocks in molecular detail.
Collapse
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.,Natural Science Division, Campbellsville University, Campbellsville, Kentucky 42718, United States
| | - Rasal H Khan
- Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | - Brandon J Butcher
- 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
| | - Alberto P Galende
- Natural Science Division, Campbellsville University, Campbellsville, Kentucky 42718, United States
| | - Robert M McCarrick
- 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
| |
Collapse
|
15
|
Krieger IV, Kuznetsov V, Chang JY, Zhang J, Moussa SH, Young RF, Sacchettini JC. The Structural Basis of T4 Phage Lysis Control: DNA as the Signal for Lysis Inhibition. J Mol Biol 2020; 432:4623-4636. [PMID: 32562709 DOI: 10.1016/j.jmb.2020.06.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 02/05/2023]
Abstract
Optimal phage propagation depends on the regulation of the lysis of the infected host cell. In T4 phage infection, lysis occurs when the holin protein (T) forms lesions in the host membrane. However, the lethal function of T can be blocked by an antiholin (RI) during lysis inhibition (LIN). LIN sets if the infected cell undergoes superinfection, then the lysis is delayed until host/phage ratio becomes more favorable for the release of progeny. It has been thought that a signal derived from the superinfection is required to activate RI. Here we report structures that suggest a radically different model in which RI binds to T irrespective of superinfection, causing it to accumulate in a membrane as heterotetrameric 2RI-2T complex. Moreover, we show the complex binds non-specifically to DNA, suggesting that the gDNA from the superinfecting phage serves as the LIN signal and that stabilization of the complex by DNA binding is what defines LIN. Finally, we show that soluble domain of free RI crystallizes in a domain-swapped homotetramer, which likely works as a sink for RI molecules released from the RI-T complex to ensure efficient lysis. These results constitute the first structural basis and a new model not only for the historic LIN phenomenon but also for the temporal regulation of phage lysis in general.
Collapse
Affiliation(s)
- Inna V Krieger
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Vladimir Kuznetsov
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Jeng-Yih Chang
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA; Center for Phage Technology, Department of Biochemistry and Biophysics
| | - Junjie Zhang
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA; Center for Phage Technology, Department of Biochemistry and Biophysics
| | - Samir H Moussa
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA; Center for Phage Technology, Department of Biochemistry and Biophysics
| | - Ryland F Young
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA; Center for Phage Technology, Department of Biochemistry and Biophysics
| | - James C Sacchettini
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA.
| |
Collapse
|
16
|
Adamczyk-Popławska M, Tracz-Gaszewska Z, Lasota P, Kwiatek A, Piekarowicz A. Haemophilus influenzae HP1 Bacteriophage Encodes a Lytic Cassette with a Pinholin and a Signal-Arrest-Release Endolysin. Int J Mol Sci 2020; 21:E4013. [PMID: 32512736 PMCID: PMC7312051 DOI: 10.3390/ijms21114013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 06/01/2020] [Accepted: 06/02/2020] [Indexed: 01/01/2023] Open
Abstract
HP1 is a temperate bacteriophage, belonging to the Myoviridae family and infecting Haemophilus influenzae Rd. By in silico analysis and molecular cloning, we characterized lys and hol gene products, present in the previously proposed lytic module of HP1 phage. The amino acid sequence of the lys gene product revealed the presence of signal-arrest-release (SAR) and muraminidase domains, characteristic for some endolysins. HP1 endolysin was able to induce lysis on its own when cloned and expressed in Escherichia coli, but the new phage release from infected H. influenzae cells was suppressed by inhibition of the secretion (sec) pathway. Protein encoded by hol gene is a transmembrane protein, with unusual C-out and N-in topology, when overexpressed/activated. Its overexpression in E. coli did not allow the formation of large pores (lack of leakage of β-galactosidase), but caused cell death (decrease in viable cell count) without lysis (turbidity remained constant). These data suggest that lys gene encodes a SAR-endolysin and that the hol gene product is a pinholin. HP1 SAR-endolysin is responsible for cell lysis and HP1 pinholin seems to regulate the cell lysis and the phage progeny release from H. influenzae cells, as new phage release from the natural host was inhibited by deletion of the hol gene.
Collapse
Affiliation(s)
- Monika Adamczyk-Popławska
- Warsaw University, Faculty of Biology, Institute of Microbiology, Department of Molecular Virology, Miecznikowa 1, 02-096 Warsaw, Poland; (Z.T.-G.); (P.L.); (A.K.); (A.P.)
| | | | | | | | | |
Collapse
|
17
|
Bavda VR, Jain V. Deciphering the Role of Holin in Mycobacteriophage D29 Physiology. Front Microbiol 2020; 11:883. [PMID: 32477303 PMCID: PMC7232613 DOI: 10.3389/fmicb.2020.00883] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 04/16/2020] [Indexed: 12/11/2022] Open
Abstract
In the era of antibiotic resistance, phage therapy is gaining attention for the treatment of pathogenic organisms such as Mycobacterium tuberculosis. The selection of phages for therapeutic purposes depends upon several factors such as the host range that a phage can infect, which can be narrow or broad, time required for the host cell lysis, and the burst size. Mycobacteriophage D29 is a virulent phage that has the ability to infect and kill several slow- and fast-growing mycobacterial species including the pathogenic M. tuberculosis. It, therefore, has the potential to be used in phage therapy against M. tuberculosis. D29 lytic cassette encodes three proteins viz. peptidoglycan hydrolase (LysA), mycolylarabinogalactan esterase (LysB), and holin, which together ensure host cell lysis in a timely manner. In this work, we have scrutinized the importance of holin in mycobacteriophage D29 physiology. Bacteriophage Recombineering of Electroporated DNA (BRED) approach was used to generate D29 holin knockout (D29Δgp11), which was further confirmed by the Deletion amplification detection assay (DADA)-PCR. Our results show that D29Δgp11 is viable and retains plaque-forming ability, although with reduced plaque size. Additionally, the host cell lysis governed by the mutant phage is significantly delayed as compared to the wild-type D29. In the absence of holin, D29 shows increased latent period and reduced burst size. Thus, our experiments show that while holin is dispensable for phage viability, it is essential for the optimal phage-mediated host cell lysis and phage propagation, which further points to the significance of the “clock” function of holin. Taken together, we show the importance of holin in governing timely and efficient host cell lysis for efficient progeny phage release, which further dictates its critical role in phage biology.
Collapse
Affiliation(s)
- Varun Rakeshbhai Bavda
- 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
| |
Collapse
|
18
|
Drew DL, Butcher B, Sahu ID, Ahammad T, Dixit G, Lorigan GA. Active S 2168 and inactive S 21IRS pinholin interact differently with the lipid bilayer: A 31P and 2H solid state NMR study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183257. [PMID: 32147355 DOI: 10.1016/j.bbamem.2020.183257] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 02/28/2020] [Accepted: 03/02/2020] [Indexed: 01/02/2023]
Abstract
Pinholins are a family of lytic membrane proteins responsible for the lysis of the cytosolic membrane in host cells of double stranded DNA bacteriophages. Protein-lipid interactions have been shown to influence membrane protein topology as well as its function. This work investigated the interactions of pinholin with the phospholipid bilayer while in active and inactive confirmations to elucidate the different interactions the two forms have with the bilayer. Pinholin incorporated into deuterated DMPC-d54 lipid bilayers, along with 31P and 2H solid state NMR (SS-NMR) spectroscopy were used to probe the protein-lipid interactions with the phosphorus head group at the surface of the bilayer while interactions with the 2H nuclei were used to study the hydrophobic core. A comparison of the 31P chemical shift anisotropy (CSA) values of the active S2168 pinholin and inactive S21IRS pinholin indicated stronger head group interactions for the pinholin in its active form when compared to that of the inactive form supporting the model of a partially externalized peripheral transmembrane domain (TMD) of the active S2168 instead of complete externalized TMD1 as suggested by Ahammad et al. JPC B 2019. The 2H quadrupolar splitting analysis showed a decrease in spectral width for both forms of the pinholin when compared to the empty bilayers at all temperatures. In this case the decrease in the spectral width of the inactive S21IRS form of the pinholin showed stronger interactions with the acyl chains of the bilayer. The presence of the inactive form's additional TMD within the membrane was supported by the loss of peak resolution observed in the 2H NMR spectra.
Collapse
Affiliation(s)
- Daniel L Drew
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| | - Brandon Butcher
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| | - Indra D Sahu
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA; Natural Science Division, Campbellsville University, Campbellsville, KY 42718, USA.
| | - Tanbir Ahammad
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| | - Gunjan Dixit
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
| |
Collapse
|
19
|
Kongari R, Rajaure M, Cahill J, Rasche E, Mijalis E, Berry J, Young R. Phage spanins: diversity, topological dynamics and gene convergence. BMC Bioinformatics 2018; 19:326. [PMID: 30219026 PMCID: PMC6139136 DOI: 10.1186/s12859-018-2342-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 08/28/2018] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Spanins are phage lysis proteins required to disrupt the outer membrane. Phages employ either two-component spanins or unimolecular spanins in this final step of Gram-negative host lysis. Two-component spanins like Rz-Rz1 from phage lambda consist of an integral inner membrane protein: i-spanin, and an outer membrane lipoprotein: o-spanin, that form a complex spanning the periplasm. Two-component spanins exist in three different genetic architectures; embedded, overlapped and separated. In contrast, the unimolecular spanins, like gp11 from phage T1, have an N-terminal lipoylation signal sequence and a C-terminal transmembrane domain to account for the topology requirements. Our proposed model for spanin function, for both spanin types, follows a common theme of the outer membrane getting fused with the inner membrane, effecting the release of progeny virions. RESULTS Here we present a SpaninDataBase which consists of 528 two-component spanins and 58 unimolecular spanins identified in this analysis. Primary analysis revealed significant differences in the secondary structure predictions for the periplasmic domains of the two-component and unimolecular spanin types, as well as within the three different genetic architectures of the two-component spanins. Using a threshold of 40% sequence identity over 40% sequence length, we were able to group the spanins into 143 i-spanin, 125 o-spanin and 13 u-spanin families. More than 40% of these families from each type were singletons, underlining the extreme diversity of this class of lysis proteins. Multiple sequence alignments of periplasmic domains demonstrated conserved secondary structure patterns and domain organization within family members. Furthermore, analysis of families with members from different architecture allowed us to interpret the evolutionary dynamics of spanin gene arrangement. Also, the potential universal role of intermolecular disulfide bonds in two-component spanin function was substantiated through bioinformatic and genetic approaches. Additionally, a novel lipobox motif, AWAC, was identified and experimentally verified. CONCLUSIONS The findings from this bioinformatic approach gave us instructive insights into spanin function, evolution, domain organization and provide a platform for future spanin annotation, as well as biochemical and genetic experiments. They also establish that spanins, like viral membrane fusion proteins, adopt different strategies to achieve fusion of the inner and outer membranes.
Collapse
Affiliation(s)
- Rohit Kongari
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX, 77843-2128, USA
| | | | - Jesse Cahill
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX, 77843-2128, USA
| | - Eric Rasche
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX, 77843-2128, USA
| | - Eleni Mijalis
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX, 77843-2128, USA
| | - Joel Berry
- University of California, San Francisco, CA, USA
| | - Ry Young
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, 2128 TAMU, College Station, TX, 77843-2128, USA.
| |
Collapse
|
20
|
van Zyl LJ, Abrahams Y, Stander EA, Kirby-McCollough B, Jourdain R, Clavaud C, Breton L, Trindade M. Novel phages of healthy skin metaviromes from South Africa. Sci Rep 2018; 8:12265. [PMID: 30115980 PMCID: PMC6095929 DOI: 10.1038/s41598-018-30705-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 07/27/2018] [Indexed: 12/15/2022] Open
Abstract
Recent skin metagenomic studies have investigated the harbored viral diversity and its possible influence on healthy skin microbial populations, and tried to establish global patterns of skin-phage evolution. However, the detail associated with the phages that potentially play a role in skin health has not been investigated. While skin metagenome and -metavirome studies have indicated that the skin virome is highly site specific and shows marked interpersonal variation, they have not assessed the presence/absence of individual phages. Here, we took a semi-culture independent approach (metaviromic) to better understand the composition of phage communities on skin from South African study participants. Our data set adds over 130 new phage species of the skin to existing databases. We demonstrated that identical phages were present on different individuals and in different body sites, and we conducted a detailed analysis of the structural organization of these phages. We further found that a bacteriophage related to the Staphylococcus capitis phage Stb20 may be a common skin commensal virus potentially regulating its host and its activities on the skin.
Collapse
Affiliation(s)
- Leonardo Joaquim van Zyl
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Robert Sobukwe Road, Bellville, Cape Town, South Africa.
| | - Yoonus Abrahams
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Robert Sobukwe Road, Bellville, Cape Town, South Africa
| | - Emily Amor Stander
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Robert Sobukwe Road, Bellville, Cape Town, South Africa
| | - Bronwyn Kirby-McCollough
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Robert Sobukwe Road, Bellville, Cape Town, South Africa
| | - Roland Jourdain
- L'Oréal Research and Innovation, 1 Avenue Eugène Schueller, 93600, Aulnay sous Bois, France
| | - Cécile Clavaud
- L'Oréal Research and Innovation, 1 Avenue Eugène Schueller, 93600, Aulnay sous Bois, France
| | - Lionel Breton
- L'Oréal Research and Innovation, 1 Avenue Eugène Schueller, 93600, Aulnay sous Bois, France
| | - Marla Trindade
- Institute for Microbial Biotechnology and Metagenomics (IMBM), University of the Western Cape, Robert Sobukwe Road, Bellville, Cape Town, South Africa
| |
Collapse
|
21
|
A Cytoplasmic Antiholin Is Embedded In Frame with the Holin in a Lactobacillus fermentum Bacteriophage. Appl Environ Microbiol 2018; 84:AEM.02518-17. [PMID: 29305511 DOI: 10.1128/aem.02518-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 12/23/2017] [Indexed: 02/02/2023] Open
Abstract
In double-stranded DNA bacteriophages, infection cycles are ended by host cell lysis through the action of phage-encoded endolysins and holins. The precise timing of lysis is regulated by the holin inhibitors, named antiholins. Sequence analysis has revealed that holins with a single transmembrane domain (TMD) are prevalent in Lactobacillus bacteriophages. A temperate bacteriophage of Lactobacillus fermentum, ϕPYB5, has a two-component lysis cassette containing endolysin Lyb5 and holin Hyb5. The hyb5 gene is 465 bp long, encoding 154 amino acid residues with an N-terminal TMD and a large cytoplasmic C-terminal domain. However, the N terminus contains no dual-start motif, suggesting that Hyb5 oligomerization could be inhibited by a specific antiholin. Two internal open reading frames in hyb5, hyb5157-465 and hyb5209-328, were identified as genes encoding putative antiholins for Hyb5 and were coexpressed in trans with lyb5-hyb5 in Escherichia coli Surprisingly, host cell lysis was delayed by Hyb5157-465 but accelerated by abolishment of the translation initiation site of this protein, indicating that Hyb5157-465 acts as an antiholin to holin Hyb5. Moreover, deletion of 45 amino acid residues at the C terminus of Hyb5 resulted in early cell lysis, even in the presence of Hyb5157-465, implying that the interaction between Hyb5157-465 and Hyb5 occurs at the C terminus of the holin. In vivo and in vitro, Hyb5157-465 and Hyb5 were detected in the cytoplasmic and membrane fractions, respectively, and pulldown assays confirmed direct interaction between Hyb5157-465 and Hyb5. All the results suggest that Hyb5157-465 is an antiholin of Hyb5 that is involved in lysis timing.IMPORTANCE Phage-encoded holins are considered to be the "molecular clock" of phage infection cycles. The interaction between a holin and its inhibitor antiholin precisely regulates the timing of lysis of the host cells. As a prominent biological group in dairy processes, phages of lactic acid bacteria (LAB) have been extensively genome sequenced. However, little is known about the antiholins of LAB phage holins and the holin-antiholin interactions. In this work, we identified an in-frame antiholin against the class III holin of Lactobacillus fermentum phage ϕPYB5, Hyb5, and demonstrated its interaction with the cognate holin, which occurred in the bacterial cytoplasm.
Collapse
|
22
|
Phage Therapy in Bacterial Infections Treatment: One Hundred Years After the Discovery of Bacteriophages. Curr Microbiol 2016; 74:277-283. [PMID: 27896482 PMCID: PMC5243869 DOI: 10.1007/s00284-016-1166-x] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 11/21/2016] [Indexed: 12/13/2022]
Abstract
The therapeutic use of bacteriophages has seen a renewal of interest blossom in the last few years. This reversion is due to increased difficulties in the treatment of antibiotic-resistant strains of bacteria. Bacterial resistance to antibiotics, a serious problem in contemporary medicine, does not implicate resistance to phage lysis mechanisms. Lytic bacteriophages are able to kill antibiotic-resistant bacteria at the end of the phage infection cycle. Thus, the development of phage therapy is potentially a way to improve the treatment of bacterial infections. However, there are antibacterial phage therapy difficulties specified by broadening the knowledge of the phage nature and influence on the host. It has been shown during experiments that both innate and adaptive immunity are involved in the clearance of phages from the body. Immunological reactions against phages are related to the route of administration and may vary depending on the type of bacterial viruses. For that reason, it is very important to test the immunological response of every single phage, particularly if intravenous therapy is being considered. The lack of these data in previous years was one of the reasons for phage therapy abandonment despite its century-long study. Promising results of recent research led us to look forward to a phage therapy that can be applied on a larger scale and subsequently put it into practice.
Collapse
|
23
|
The Last r Locus Unveiled: T4 RIII Is a Cytoplasmic Antiholin. J Bacteriol 2016; 198:2448-57. [PMID: 27381920 DOI: 10.1128/jb.00294-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 06/27/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The latent period of phage T4, normally ∼25 min, can be extended indefinitely if the infected cell is superinfected after 5 min. This phenomenon, designated lysis inhibition (LIN), was first described in the 1940s and is genetically defined by mutations in diverse T4 r genes. RI, the main effector of LIN, has been shown to be secreted to the periplasm, where, upon activation by superinfection with a T-even virion, it binds to the C-terminal periplasmic domain of the T4 holin T and blocks its lethal permeabilization of the cytoplasmic membrane. Another r locus, rIII, has been the subject of conflicting reports. In this study, we show that RIII, an 82-amino-acid protein, is also required for LIN in both Escherichia coli B strains and E. coli K-12 strains. In T4ΔrIII infections, LIN was briefly established but was unstable. The overexpression of a cloned rIII gene alone impeded T-mediated lysis temporarily. However, coexpression of rIII and rI resulted in a stable LIN state. Bacterial two-hybrid assays and pulldown assays showed that RIII interacts with the cytoplasmic N terminus of T, which is a critical domain for holin function. We conclude that RIII is a T4 antiholin that blocks membrane hole formation by interacting directly with the holin. Accordingly, we propose an augmented model for T4 LIN that involves the stabilization of a complex of three proteins in two compartments of the cell: RI interacting with the C terminus of T in the periplasm and RIII interacting with the N terminus of T in the cytoplasm. IMPORTANCE Lysis inhibition is a unique feature of phage T4 in response to environmental conditions, effected by the antiholin RI, which binds to the periplasmic domain of the T holin and blocks its hole-forming function. Here we report that the T4 gene rIII encodes a cytoplasmic antiholin that, together with the main antiholin, RI, inhibits holin T by forming a complex of three proteins spanning two cell compartments.
Collapse
|
24
|
Casjens SR, Hendrix RW. Bacteriophage lambda: Early pioneer and still relevant. Virology 2015; 479-480:310-30. [PMID: 25742714 PMCID: PMC4424060 DOI: 10.1016/j.virol.2015.02.010] [Citation(s) in RCA: 182] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 01/13/2015] [Accepted: 02/05/2015] [Indexed: 12/14/2022]
Abstract
Molecular genetic research on bacteriophage lambda carried out during its golden age from the mid-1950s to mid-1980s was critically important in the attainment of our current understanding of the sophisticated and complex mechanisms by which the expression of genes is controlled, of DNA virus assembly and of the molecular nature of lysogeny. The development of molecular cloning techniques, ironically instigated largely by phage lambda researchers, allowed many phage workers to switch their efforts to other biological systems. Nonetheless, since that time the ongoing study of lambda and its relatives has continued to give important new insights. In this review we give some relevant early history and describe recent developments in understanding the molecular biology of lambda's life cycle.
Collapse
Affiliation(s)
- Sherwood R Casjens
- Division of Microbiology and Immunology, Pathology Department, University of Utah School of Medicine, Emma Eccles Jones Medical Research Building, 15 North Medical Drive East, Salt Lake City, UT 84112, USA; Biology Department, University of Utah, Salt Lake City, UT 84112, USA.
| | - Roger W Hendrix
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| |
Collapse
|