1
|
Selective Detection of Legionella pneumophila Serogroup 1 and 5 with a Digital Photocorrosion Biosensor Using Antimicrobial Peptide-Antibody Sandwich Strategy. BIOSENSORS 2022; 12:bios12020105. [PMID: 35200365 PMCID: PMC8869675 DOI: 10.3390/bios12020105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 02/02/2022] [Accepted: 02/02/2022] [Indexed: 11/17/2022]
Abstract
Rapid detection of Legionella pneumophila (L. pneumophila) is important for monitoring the presence of these bacteria in water sources and preventing the transmission of the Legionnaires’ disease. We report improved biosensing of L. pneumophila with a digital photocorrosion (DIP) biosensor functionalized with an innovative structure of cysteine-modified warnericin antimicrobial peptides for capturing bacteria that are subsequently decorated with anti-L. pneumophila polyclonal antibodies (pAbs). The application of peptides for the operation of a biosensing device was enabled by the higher bacterial-capture efficiency of peptides compared to other traditional ligands, such as those based on antibodies or aptamers. At the same time, the significantly stronger affinity of pAbs decorating the L. pneumophila serogroup-1 (SG-1) compared to serogroup-5 (SG-5) allowed for the selective detection of L. pneumophila SG-1 at 50 CFU/mL. The results suggest that the attractive sensitivity of the investigated sandwich method is related to the flow of an extra electric charge between the pAb and a charge-sensing DIP biosensor. The method has the potential to offer highly specific and sensitive detection of L. pneumophila as well as other pathogenic bacteria and viruses.
Collapse
|
2
|
Cytotoxicity, Intracellular Replication, and Contact-Dependent Pore Formation of Genotyped Environmental Legionella pneumophila Isolates from Hospital Water Systems in the West Bank, Palestine. Pathogens 2021; 10:pathogens10040417. [PMID: 33915921 PMCID: PMC8066006 DOI: 10.3390/pathogens10040417] [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: 02/27/2021] [Revised: 03/15/2021] [Accepted: 03/28/2021] [Indexed: 12/02/2022] Open
Abstract
Legionella pneumophila is the causative agent of Legionnaires’ disease. Due to the hot climate and intermittent water supply, the West Bank, Palestine, can be considered a high-risk area for this often fatal atypical pneumonia. L. pneumophila occurs in biofilms of natural and man-made freshwater environments, where it infects and replicates intracellularly within protozoa. To correlate the genetic diversity of the bacteria in the environment with their virulence properties for protozoan and mammalian host cells, 60 genotyped isolates from hospital water systems in the West Bank were analyzed. The L. pneumophila isolates were previously genotyped by high resolution Multi Locus Variable Number of Tandem Repeat Analysis (MLVA-8(12)) and sorted according to their relationship in clonal complexes (VACC). Strains of relevant genotypes and VACCs were compared according to their capacity to infect Acanthamoeba castellanii and THP-1 macrophages, and to mediate pore-forming cytotoxicity in sheep red blood cells (sRBCs). Based on a previous detailed analysis of the biogeographic distribution and abundance of the MLVA-8(12)-genotypes, the focus of the study was on the most abundant L. pneumophila- genotypes Gt4(17), Gt6 (18) and Gt10(93) and the four relevant clonal complexes [VACC1, VACC2, VACC5 and VACC11]. The highly abundant genotypes Gt4(17) and Gt6(18) are affiliated with VACC1 and sequence type (ST)1 (comprising L. pneumophila str. Paris), and displayed seroroup (Sg)1. Isolates of these two genotypes exhibited significantly higher virulence potentials compared to other genotypes and clonal complexes in the West Bank. Endemic for the West Bank was the clonal complex VACC11 (affiliated with ST461) represented by three relevant genotypes that all displayed Sg6. These genotypes unique for the West Bank showed a lower infectivity and cytotoxicity compared to all other clonal complexes and their affiliated genotypes. Interestingly, the L. pneumophila serotypes ST1 and ST461 were previously identified by in situ-sequence based typing (SBT) as main causative agents of Legionnaires’ disease (LD) in the West Bank at a comparable level. Overall, this study demonstrates the site-specific regional diversity of L. pneumophila genotypes in the West Bank and suggests that a combination of MLVA, cellular infection assays and hierarchical agglomerative cluster analysis allows an improved genotype-based risk assessment.
Collapse
|
3
|
Luiz de Freitas L, Pereira da Silva F, Fernandes KM, Carneiro DG, Licursi de Oliveira L, Martins GF, Dantas Vanetti MC. The virulence of Salmonella Enteritidis in Galleria mellonella is improved by N-dodecanoyl-homoserine lactone. Microb Pathog 2021; 152:104730. [PMID: 33444697 DOI: 10.1016/j.micpath.2021.104730] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 01/01/2021] [Accepted: 01/03/2021] [Indexed: 01/18/2023]
Abstract
Salmonella is a food and waterborne pathogen responsible for outbreaks worldwide, and it can survive during passage through the stomach and inside host phagocytic cells. Virulence genes are required for infection and survival in macrophages, and some are under the regulation of the quorum sensing (QS) system. This study investigated the influence of the autoinducer 1 (AI-1), N-dodecanoyl-homoserine lactone (C12-HSL), on the virulence of Salmonella PT4 using Galleria mellonella as an infection model. Salmonella PT4 was grown in the presence and absence of C12-HSL under anaerobic conditions for 7 h, and the expression of rpoS, arcA, arcB, and invA genes was evaluated. After the inoculation of G. mellonella with the median lethal dose (LD50) of Salmonella PT4, the survival of bacteria inside the larvae and their health status (health index scoring) were monitored, as well as the pigment, nitric oxide (NO), superoxide dismutase (SOD), and catalase (CAT) production. Also, the hemocyte viability, the induction of caspase-3, and microtubule-associated light chain 3 (LC3) protein in hemocytes were evaluated. Salmonella PT4 growing in the presence of C12-HSL showed increased rpoS, arcA, arcB, and invA expression and promoted higher larvae mortality and worse state of health after 24 h of infection. The C12-HSL also increased the persistence of Salmonella PT4 in the hemolymph and in the hemocytes. The highest pigmentation, NO production, and antioxidant enzymes were verified in the larva hemolymph infected with Salmonella PT4 grown with C12-HSL. Hemocytes from larvae infected with Salmonella PT4 grown with C12-HSL showed lower viability and higher production of caspase-3 and LC3. Taken together, these findings suggest that C12-HSL could be involved in the virulence of Salmonella PT4.
Collapse
Affiliation(s)
- Leonardo Luiz de Freitas
- Departmento de Microbiologia, Universidade Federal de Viçosa (UFV), Viçosa, Minas Gerais, Brazil
| | | | - Kenner Morais Fernandes
- Departamento de Biologia Geral, Universidade Federal de Viçosa (UFV), Viçosa, Minas Gerais, Brazil
| | - Deisy Guimarães Carneiro
- Departmento de Microbiologia, Universidade Federal de Viçosa (UFV), Viçosa, Minas Gerais, Brazil
| | | | - Gustavo Ferreira Martins
- Departamento de Biologia Geral, Universidade Federal de Viçosa (UFV), Viçosa, Minas Gerais, Brazil
| | | |
Collapse
|
4
|
Pereira MF, Rossi CC. Overview of rearing and testing conditions and a guide for optimizing Galleria mellonella breeding and use in the laboratory for scientific purposes. APMIS 2020; 128:607-620. [PMID: 32970339 DOI: 10.1111/apm.13082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The greater wax moth Galleria mellonella is an increasingly popular and consolidated alternative infection model to assess microbial virulence and the effectiveness of antimicrobial compounds. The lack of G. mellonella suppliers aiming at scientific purposes and a lack of well-established protocols for raising and testing these animals may impact results and reproducibility between different laboratories. In this review, we discuss the state of the art of rearing the larvae in situ, providing an overview of breeding and testing conditions commonly used and their influence on larval health and experiments results, from setting up the environment, providing the ideal diet, understanding the effects of pretreatments, choosing the best testing conditions, to exploring the most from the results obtained. Meanwhile, we guide the reader through the most practical ways of dealing with G. mellonella to achieve successful experiments.
Collapse
Affiliation(s)
- Monalessa Fábia Pereira
- Laboratório de Bioquímica e Microbiologia, Departamento de Ciências Biológicas, Universidade do Estado de Minas Gerais, Carangola, MG, Brazil
| | - Ciro César Rossi
- Laboratório de Microbiologia Molecular, Departamento de Microbiologia Médica, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| |
Collapse
|
5
|
Aravena P, Pulgar R, Ortiz-Severín J, Maza F, Gaete A, Martínez S, Serón E, González M, Cambiazo V. PCR-RFLP Detection and Genogroup Identification of Piscirickettsia salmonis in Field Samples. Pathogens 2020; 9:pathogens9050358. [PMID: 32397152 PMCID: PMC7281544 DOI: 10.3390/pathogens9050358] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 04/28/2020] [Accepted: 04/30/2020] [Indexed: 02/01/2023] Open
Abstract
Piscirickettsia salmons, the causative agent of piscirickettsiosis, is genetically divided into two genomic groups, named after the reference strains as LF-89-like or EM-90-like. Phenotypic differences have been detected between the P. salmonis genogroups, including antibiotic susceptibilities, host specificities and pathogenicity. In this study, we aimed to develop a rapid, sensitive and cost-effective assay for the differentiation of the P. salmonis genogroups. Using an in silico analysis of the P. salmonis 16S rDNA digestion patterns, we have designed a genogroup-specific assay based on PCR-restriction fragment length polymorphism (RFLP). An experimental validation was carried out by comparing the restriction patterns of 13 P. salmonis strains and 57 field samples obtained from the tissues of dead or moribund fish. When the bacterial composition of a set of field samples, for which we detected mixtures of bacterial DNA, was analyzed by a high-throughput sequencing of the 16S rRNA gene amplicons, a diversity of taxa could be identified, including pathogenic and commensal bacteria. Despite the presence of mixtures of bacterial DNA, the characteristic digestion pattern of the P. salmonis genogroups could be detected in the field samples without the need of a microbiological culture and bacterial isolation.
Collapse
Affiliation(s)
- Pamela Aravena
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago 7830490, Chile; (P.A.); (R.P.); (J.O.-S.); (F.M.); (A.G.); (M.G.)
- FONDAP Center for Genome Regulation, Santiago 8370415, Chile
| | - Rodrigo Pulgar
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago 7830490, Chile; (P.A.); (R.P.); (J.O.-S.); (F.M.); (A.G.); (M.G.)
| | - Javiera Ortiz-Severín
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago 7830490, Chile; (P.A.); (R.P.); (J.O.-S.); (F.M.); (A.G.); (M.G.)
| | - Felipe Maza
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago 7830490, Chile; (P.A.); (R.P.); (J.O.-S.); (F.M.); (A.G.); (M.G.)
- FONDAP Center for Genome Regulation, Santiago 8370415, Chile
| | - Alexis Gaete
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago 7830490, Chile; (P.A.); (R.P.); (J.O.-S.); (F.M.); (A.G.); (M.G.)
- FONDAP Center for Genome Regulation, Santiago 8370415, Chile
| | - Sebastián Martínez
- Laboratorio Especialidades Técnicas Marinas (ETECMA), Puerto Montt 5500001, Chile; (S.M.); (E.S.)
| | - Ervin Serón
- Laboratorio Especialidades Técnicas Marinas (ETECMA), Puerto Montt 5500001, Chile; (S.M.); (E.S.)
| | - Mauricio González
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago 7830490, Chile; (P.A.); (R.P.); (J.O.-S.); (F.M.); (A.G.); (M.G.)
- FONDAP Center for Genome Regulation, Santiago 8370415, Chile
| | - Verónica Cambiazo
- Laboratorio de Bioinformática y Expresión Génica, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago 7830490, Chile; (P.A.); (R.P.); (J.O.-S.); (F.M.); (A.G.); (M.G.)
- FONDAP Center for Genome Regulation, Santiago 8370415, Chile
- Correspondence:
| |
Collapse
|
6
|
Kamal F, Peters DL, McCutcheon JG, Dunphy GB, Dennis JJ. Use of Greater Wax Moth Larvae (Galleria mellonella) as an Alternative Animal Infection Model for Analysis of Bacterial Pathogenesis. Methods Mol Biol 2019; 1898:163-171. [PMID: 30570731 DOI: 10.1007/978-1-4939-8940-9_13] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Alternative infection models of bacterial pathogenesis are useful because they reproduce some of the disease characteristics observed in higher animals. Insect models are especially useful for modeling bacterial infections, as they are inexpensive, generally less labor-intensive, and more ethically acceptable than experimentation on higher organisms. Similar to animals, insects have been shown to possess innate immune systems that respond to pathogenic bacteria.
Collapse
Affiliation(s)
- Fatima Kamal
- Faculty of Science, Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Danielle L Peters
- Faculty of Science, Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Jaclyn G McCutcheon
- Faculty of Science, Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Gary B Dunphy
- Natural Resource Sciences, Faculty of Agricultural and Environmental Sciences, McGill University, Montreal, QC, Canada
| | - Jonathan J Dennis
- Faculty of Science, Biological Sciences, University of Alberta, Edmonton, AB, Canada.
| |
Collapse
|
7
|
The Galleria mellonella Infection Model for Investigating the Molecular Mechanisms of Legionella Virulence. Methods Mol Biol 2019; 1921:333-346. [PMID: 30694503 DOI: 10.1007/978-1-4939-9048-1_22] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Legionella species evolved virulence factors to exploit protozoa as replicative niches in the environment. Cell culture infection models demonstrated that many of these factors also enable the bacteria to thrive in human macrophages; however, these models do not recapitulate the complex interactions between macrophages, lung epithelial, and additional immune cells, which are crucial to control bacterial infections. Thus, suitable infection models are required to understand which bacterial factors are important to trigger disease. Guinea pigs and, most frequently, mice have been successfully used as mammalian model hosts; however, ethical and economic considerations impede their use in high-throughput screening studies of Legionella isolates or small molecule inhibitors.Here, we describe the larvae of the lepidopteran Galleria mellonella as insect model of Legionella pathogenesis. Larvae can be obtained from commercial suppliers in large numbers, maintained without the need of specialized equipment, and infected by injection. Although lacking the complexity of a mammalian immune system, the larvae mount humoral and cellular immune responses to infection. L. pneumophila strain 130b and other prototype isolates withstand these responses and use the Defective in organelle trafficking/Intracellular multiplication (Dot/Icm) type IV secretion system (T4SS ) to inject effectors enabling survival and replication in hemocytes, insect phagocytes, ultimately leading to the death of the larvae. Differences in virulence between L. pneumophila isolates or gene deletion mutants can be analyzed using indicators of larval health and immune induction, such as pigmentation, mobility, histopathology, and survival. Bacterial replication can be measured by plating hemolymph or by immunofluorescence microscopy of isolated circulating hemocytes from infected larvae. Combined, these straightforward experimental readouts make G. mellonella larvae a versatile model host to rapidly assess the virulence of different Legionella isolates and investigate the role of specific virulence factors in overcoming innate host defense mechanisms.
Collapse
|
8
|
Best AM, Abu Kwaik Y. Evasion of phagotrophic predation by protist hosts and innate immunity of metazoan hosts by Legionella pneumophila. Cell Microbiol 2018; 21:e12971. [PMID: 30370624 DOI: 10.1111/cmi.12971] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 10/08/2018] [Accepted: 10/24/2018] [Indexed: 12/18/2022]
Abstract
Legionella pneumophila is a ubiquitous environmental bacterium that has evolved to infect and proliferate within amoebae and other protists. It is thought that accidental inhalation of contaminated water particles by humans is what has enabled this pathogen to proliferate within alveolar macrophages and cause pneumonia. However, the highly evolved macrophages are equipped with more sophisticated innate defence mechanisms than are protists, such as the evolution of phagotrophic feeding into phagocytosis with more evolved innate defence processes. Not surprisingly, the majority of proteins involved in phagosome biogenesis (~80%) have origins in the phagotrophy stage of evolution. There are a plethora of highly evolved cellular and innate metazoan processes, not represented in protist biology, that are modulated by L. pneumophila, including TLR2 signalling, NF-κB, apoptotic and inflammatory processes, histone modification, caspases, and the NLRC-Naip5 inflammasomes. Importantly, L. pneumophila infects haemocytes of the invertebrate Galleria mellonella, kill G. mellonella larvae, and proliferate in and kill Drosophila adult flies and Caenorhabditis elegans. Although coevolution with protist hosts has provided a substantial blueprint for L. pneumophila to infect macrophages, we discuss the further evolutionary aspects of coevolution of L. pneumophila and its adaptation to modulate various highly evolved innate metazoan processes prior to becoming a human pathogen.
Collapse
Affiliation(s)
- Ashley M Best
- Department of Microbiology and Immunology, College of Medicine, University of Louisville, Louisville, Kentucky
| | - Yousef Abu Kwaik
- Department of Microbiology and Immunology, College of Medicine, University of Louisville, Louisville, Kentucky.,Center for Predictive Medicine, College of Medicine, University of Louisville, Louisville, Kentucky
| |
Collapse
|
9
|
Abstract
Within the human host, Legionella pneumophila replicates within alveolar macrophages, leading to pneumonia. However, L. pneumophila is an aquatic generalist pathogen that replicates within a wide variety of protist hosts, including amoebozoa, percolozoa, and ciliophora. The intracellular lifestyles of L. pneumophila within the two evolutionarily distant hosts macrophages and protists are remarkably similar. Coevolution with numerous protist hosts has shaped plasticity of the genome of L. pneumophila, which harbors numerous proteins encoded by genes acquired from primitive eukaryotic hosts through interkingdom horizontal gene transfer. The Dot/Icm type IVb translocation system translocates ∼6,000 effectors among Legionella species and >320 effector proteins in L. pneumophila into host cells to modulate a plethora of cellular processes to create proliferative niches. Since many of the effectors have likely evolved to modulate cellular processes of primitive eukaryotic hosts, it is not surprising that most of the effectors do not contribute to intracellular growth within human macrophages. Some of the effectors may modulate highly conserved eukaryotic processes, while others may target protist-specific processes that are absent in mammals. The lack of studies to determine the role of the effectors in adaptation of L. pneumophila to various protists has hampered the progress to determine the function of most of these effectors, which are routinely studied in mouse or human macrophages. Since many protists restrict L. pneumophila, utilization of such hosts can also be instrumental in deciphering the mechanisms of failure of L. pneumophila to overcome restriction of certain protist hosts. Here, we review the interaction of L. pneumophila with its permissive and restrictive protist environmental hosts and outline the accomplishments as well as gaps in our knowledge of L. pneumophila-protist host interaction and L. pneumophila's evolution to become a human pathogen.
Collapse
Affiliation(s)
- Ashley Best
- Department of Microbiology and Immunology, School of Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Yousef Abu Kwaik
- Department of Microbiology and Immunology, School of Medicine, University of Louisville, Louisville, Kentucky, USA
- Center for Predictive Medicine, University of Louisville, Louisville, Kentucky, USA
| |
Collapse
|