Mycoplasma Pathogenicity, Persistence and Virulence

A special issue of Microorganisms (ISSN 2076-2607). This special issue belongs to the section "Molecular Microbiology and Immunology".

Deadline for manuscript submissions: closed (31 March 2023) | Viewed by 21869

Special Issue Editors

Institute of Microbiology, University of Veterinary Medicine Vienna, 1210 Wien, Austria
Interests: Mycoplasma agalactiae; antigenic variation; phase-locked mutants; immune evasion; in vitro and in vivo infection models; pathogenicity determinants
Multidisciplinary Institute of Health, Federal University of Bahia, Salvador 40170-110, Bahia, Brazil
Interests: animal mycoplasma; human mycoplasma; virulence; pathogenicity; immune response

Special Issue Information

Dear Colleagues,

Despite their small genomes, mycoplasmas are successful pathogens of both humans and animals and mostly cause chronic and difficult-to-eradicate diseases. Antibiotics are either ineffective or too expensive, and there is a dearth of good vaccines. Most of the mycoplasma pathogens lack typical virulence factors, as seen in other bacteria, and although several genomes have been sequenced, their pathogenicity mechanisms are still not well understood. However, the last two decades have driven the need to develop new molecular genetic analysis tools to dissect their cell biology, especially in the context of survival and subversion strategies within immunocompetent hosts. Combined with several omics, this research would provide a better understanding of mycoplasma infections, hopefully leading to better anti-infectives.  

With this Special Issue, we hope to offer a multidisciplinary platform for submissions that provide a current snapshot of research on various aspects of mycoplasma pathogenicity, ranging from the basic relevant biology influencing their pathogenic lifestyle to experimental in vivo and in vitro infections, virulence, and persistence mechanisms; host immune responses to mycoplasma antigens, nucleases, and biofilms; and other topics including, but not limited to, the ‘keywords’ listed below.

  • Mycoplasma sp;
  • surface lipoproteins;
  • mycoplasma host interactions;
  • cytadhesion and invasion;
  • antigenic/phase variation;
  • immune responses;
  • pathogenicity and virulence;
  • antibiotics and vaccines;
  • omics.

Dr. Rohini Chopra-Dewasthaly
Dr. Lucas Miranda Marques
Guest Editors

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Published Papers (11 papers)

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Research

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24 pages, 6341 KiB  
Article
Characterisation of Type II DNA Methyltransferases of Metamycoplasma hominis
by Lars Vogelgsang, Azlan Nisar, Sebastian Alexander Scharf, Anna Rommerskirchen, Dana Belick, Alexander Dilthey and Birgit Henrich
Microorganisms 2023, 11(6), 1591; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms11061591 - 15 Jun 2023
Viewed by 1938
Abstract
Bacterial virulence, persistence and defence are affected by epigenetic modifications, including DNA methylation. Solitary DNA methyltransferases modulate a variety of cellular processes and influence bacterial virulence; as part of a restriction-modification (RM) system, they act as a primitive immune system in methylating the [...] Read more.
Bacterial virulence, persistence and defence are affected by epigenetic modifications, including DNA methylation. Solitary DNA methyltransferases modulate a variety of cellular processes and influence bacterial virulence; as part of a restriction-modification (RM) system, they act as a primitive immune system in methylating the own DNA, while unmethylated foreign DNA is restricted. We identified a large family of type II DNA methyltransferases in Metamycoplasma hominis, comprising six solitary methyltransferases and four RM systems. Motif-specific 5mC and 6mA methylations were identified with a tailored Tombo analysis on Nanopore reads. Selected motifs with methylation scores >0.5 fit with the gene presence of DAM1 and DAM2, DCM2, DCM3, and DCM6, but not for DCM1, whose activity was strain-dependent. The activity of DCM1 for CmCWGG and of both DAM1 and DAM2 for GmATC was proven in methylation-sensitive restriction and finally for recombinant rDCM1 and rDAM2 against a dam-, dcm-negative background. A hitherto unknown dcm8/dam3 gene fusion containing a (TA) repeat region of varying length was characterized within a single strain, suggesting the expression of DCM8/DAM3 phase variants. The combination of genetic, bioinformatics, and enzymatic approaches enabled the detection of a huge family of type II DNA MTases in M. hominis, whose involvement in virulence and defence can now be characterized in future work. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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10 pages, 723 KiB  
Article
Clinical, Laboratory, and Radiographic Features Can Help Predict Mycoplasma pneumoniae Lower Respiratory Tract Infection in Children
by Jasna Rodman Berlot, Špela Dolenc, Uroš Krivec and Darja Keše
Microorganisms 2023, 11(5), 1358; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms11051358 - 22 May 2023
Viewed by 1198
Abstract
Mycoplasma pneumoniae (Mp) is a common cause of lower respiratory tract infection (LRTI) in children that is difficult to distinguish from LRTI of other etiologies. We aimed to determine if a combination of clinical, laboratory, and chest radiographic features can help identify patients [...] Read more.
Mycoplasma pneumoniae (Mp) is a common cause of lower respiratory tract infection (LRTI) in children that is difficult to distinguish from LRTI of other etiologies. We aimed to determine if a combination of clinical, laboratory, and chest radiographic features can help identify patients at higher risk of Mp LRTI. We reviewed medical charts of children referred to our tertiary hospital with suspected acute mycoplasmal LRTI. Pharyngeal swabs obtained from patients were tested by Mp PCR. We compared epidemiological and clinical data of children with positive and negative Mp PCR results. In addition, a multivariable logistic regression analysis was performed to predict Mp LRTI based on the patient’s age, duration of symptoms, presence of extrapulmonary manifestations, laboratory findings, and chest radiographic findings. We included 65 children with Mp PCR-negative and 49 with Mp PCR-positive LRTI and no viral co-detection. Children with Mp LRTI were older (median age 5.8 vs. 2.2 years, p < 0.001), had a longer duration of symptoms on referral (median 7 vs. 4 days, p < 0.001), and lower median WBC (9.9 vs. 12.7 × 109/L, p < 0.001). On chest radiograph, unilateral infiltrates were more frequently observed in the Mp PCR-positive group (57.5% vs. 24.1%, p = 0.001). Age, duration of symptoms, and chest radiographic findings had the highest predictive value for Mp LRTI in a multivariable logistic regression model. Our analysis suggests that a combination of clinical, laboratory, and chest radiographic features can be used to assess the likelihood of Mp LRTI and assist in decision-making for which children need further tests or macrolide antibiotic treatment. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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19 pages, 3318 KiB  
Article
First Report and Comparative Genomic Analysis of Mycoplasma capricolum subsp. capricolum HN-B in Hainan Island, China
by Zhenxing Zhang, Meirong He, Junming Jiang, Xubo Li, Haoyang Li, Wencan Zhang, Si Chen, Li Du, Churiga Man, Qiaoling Chen, Hongyan Gao and Fengyang Wang
Microorganisms 2022, 10(11), 2298; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10112298 - 19 Nov 2022
Viewed by 1471
Abstract
Mycoplasma capricolum subsp. Capricolum (Mcc) is an important member of the Mycoplasma mycoides cluster (Mm cluster) and causes caprine contagious agalactia. Mcc can infect goats of all age groups, especially pregnant ewes and kids. It can cause the abortion in pregnant ewes and [...] Read more.
Mycoplasma capricolum subsp. Capricolum (Mcc) is an important member of the Mycoplasma mycoides cluster (Mm cluster) and causes caprine contagious agalactia. Mcc can infect goats of all age groups, especially pregnant ewes and kids. It can cause the abortion in pregnant ewes and the death of goat kids, leading to enormous losses in the goat breeding industry. To date, the prevalence of epidemic Mcc strains on Hainan Island, China, remains unclear. This study aimed to isolate and identify Mcc strains endemic to Hainan Island, China. Genome sequencing and comparative genomic analysis were performed to reveal the molecular characteristics and evolutionary relationships of the isolated strain. Mcc HN-B was isolated and identified in Hainan Island, China. The Mcc HN-B genome consists of a 1,117,925 bp circular chromosome with a 23.79% G + C content. It contains 912 encoding genes, 3 gene islands, and 14 potential virulence genes. The core genome with the features of the Mm cluster and the specific genes of Mcc HN-B were identified by comparative genomic analysis. These results revealed the evolutionary relationship between Mcc HN-B and other members of the Mm cluster. Our findings provide a reference for further studies on the pathogenic mechanism and local vaccine development of Mcc. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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14 pages, 3835 KiB  
Article
Lipoproteins Are Potent Activators of Nuclear Factor Kappa B in Mammary Epithelial Cells and Virulence Factors in Mycoplasma bovis Mastitis
by Peleg Schneider, Re’ella Brill, Iftach Schouten, Einat Nissim-Eliraz, Inna Lysnyansky and Nahum Yehuda Shpigel
Microorganisms 2022, 10(11), 2209; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10112209 - 08 Nov 2022
Cited by 2 | Viewed by 1353
Abstract
Mastitis due to Mycoplasma bovis is a worldwide problem, which leads to significant economic losses and affects animal welfare. However, the mechanisms by which M. bovis establishes and maintains intra-mammary infections (IMI) in dairy cows are largely unknown. To study in further detail [...] Read more.
Mastitis due to Mycoplasma bovis is a worldwide problem, which leads to significant economic losses and affects animal welfare. However, the mechanisms by which M. bovis establishes and maintains intra-mammary infections (IMI) in dairy cows are largely unknown. To study in further detail the pathogenesis of M. bovis IMI, time- and cost-effective experimental models are needed. To this end, we established and characterized an in vitro murine mammary alveolar epithelial (EpH4) cell-based model and an in vivo murine mastitis model. Our results showed that live and UV-treated M. bovis field strain 161791 and its lipid-associated membrane proteins (LAMP) activated nuclear factor kappa B (NF-kB) in EpH4 cells in a dose-dependent manner. In the murine mastitis model, temporal and spatial dynamics of inflammation in the mammary tissues were evident. Live M. bovis elicited diffuse inflammation affecting the whole challenged gland peaking at 48 h post infection (pi) in contrast to LAMP challenge, which elicited only focal inflammation peaking at 24 h and resolving at 48 h pi. Inflammation was characterized by massive neutrophil recruitment into the milk spaces and by elevated expression of the inflammatory mediators TNF-α, KC, iNOS and NF-kB dependent genes: A20 and IkBα. Moreover, the presence of intraepithelial bacterial communities in glands challenged with live M. bovis bacteria was shown. The developed models can be used efficiently for future characterization of M. bovis virulence factors and host immune response to IMI. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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16 pages, 1421 KiB  
Article
Mycoplasma hominis Causes DNA Damage and Cell Death in Primary Human Keratinocytes
by Aline Teixeira Amorim, Vanesca de Souza Lino, Lucas Miranda Marques, Davi Jardim Martins, Antonio Carlos Ricardo Braga Junior, Guilherme Barreto Campos, Caline Novais Teixeira Oliveira, Enrique Boccardo and Jorge Timenetsky
Microorganisms 2022, 10(10), 1962; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10101962 - 01 Oct 2022
Cited by 1 | Viewed by 2122
Abstract
Mycoplasma hominis can be isolated from the human urogenital tract. However, its interaction with the host remains poorly understood. In this study, we aimed to assess the effects of M. hominis infection on primary human keratinocytes (PHKs). Cells were quantified at different phases [...] Read more.
Mycoplasma hominis can be isolated from the human urogenital tract. However, its interaction with the host remains poorly understood. In this study, we aimed to assess the effects of M. hominis infection on primary human keratinocytes (PHKs). Cells were quantified at different phases of the cell cycle. Proteins involved in cell cycle regulation and apoptosis progression were evaluated. The expression of genes encoding proteins that are associated with the DNA damage response and Toll-like receptor pathways was evaluated, and the cytokines involved in inflammatory responses were quantified. A greater number of keratinocytes were observed in the Sub-G0/G1 phase after infection with M. hominis. In the viable keratinocytes, infection resulted in G2/M-phase arrest; GADD45A expression was increased, as was the expression of proteins such as p53, p27, and p21 and others involved in apoptosis regulation and oxidative stress. In infected PHKs, the expression of genes associated with the Toll-like receptor pathways showed a change, and the production of IFN-γ, interleukin (IL) 1β, IL-18, IL-6, and tumour necrosis factor alpha increased. The infection of PHKs by M. hominis causes cellular damage that can affect the cell cycle by activating the response pathways to cellular damage, oxidative stress, and Toll-like receptors. Overall, this response culminated in the reduction of cell proliferation/viability in vitro. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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14 pages, 1542 KiB  
Article
An Update of Bovine Hemoplasmas Based on Phylogenetic and Genomics Analysis
by Diana Laura Flores-García, Hugo Aguilar-Díaz, Itzel Amaro-Estrada, Fernando Martínez-Ocampo and Rosa Estela Quiroz-Castañeda
Microorganisms 2022, 10(10), 1916; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10101916 - 27 Sep 2022
Cited by 1 | Viewed by 1287
Abstract
Mycoplasma wenyonii and ‘Candidatus Mycoplasma haemobos’ are bacteria that have been described as significant hemoplasmas that infect cattle worldwide. Currently, three bovine hemoplasma genomes are known. This work aimed to describe the main genomic characteristics and the evolutionary relationships between hemoplasmas, and [...] Read more.
Mycoplasma wenyonii and ‘Candidatus Mycoplasma haemobos’ are bacteria that have been described as significant hemoplasmas that infect cattle worldwide. Currently, three bovine hemoplasma genomes are known. This work aimed to describe the main genomic characteristics and the evolutionary relationships between hemoplasmas, and provide a list of epitopes predicted by immunoinformatics as diagnostic candidates for bovine hemoplasmosis. Thus far, there is no vaccine to prevent this disease that economically impacts cattle production worldwide. Additionally, there is a lack of vaccines against bovine hemoplasmosis. In this work, we performed a genomic characterization of hemoplasmas, including two Mexican strains reported in bovines in the last few years. The generated information is a new scenario about the phylogeny of hemoplasmas. Also, we show genomic features among hemoplasmas that strengthen their characteristic genome plasticity of intracellular lifestyles. Finally, the elucidation of antigenic proteins in Mexican strains represents an opportunity to develop molecular detection methods and diagnoses. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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17 pages, 1806 KiB  
Article
First Report and Comparative Genomic Analysis of a Mycoplasma mycoides Subspecies capri HN-A in Hainan Island
by Zhenxing Zhang, Junming Jiang, Meirong He, Haoyang Li, Yiwen Cheng, Qi An, Si Chen, Li Du, Churiga Man, Qiaoling Chen, Lianbin Li and Fengyang Wang
Microorganisms 2022, 10(10), 1908; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10101908 - 26 Sep 2022
Cited by 8 | Viewed by 1624
Abstract
Mycoplasma mycoides subspecies capri (Mmc) is one of the six Mycoplasma mycoides cluster (Mm cluster) members, which can cause “MAKePS” (Mastitis, Arthritis, Keratoconjunctivitis, Pneumonia, Septicemia) syndrome in ruminants. These symptoms can occur alone or together in individuals or flocks of goats. However, little [...] Read more.
Mycoplasma mycoides subspecies capri (Mmc) is one of the six Mycoplasma mycoides cluster (Mm cluster) members, which can cause “MAKePS” (Mastitis, Arthritis, Keratoconjunctivitis, Pneumonia, Septicemia) syndrome in ruminants. These symptoms can occur alone or together in individuals or flocks of goats. However, little is known about the epidemic Mmc strains in Hainan Island, China. We aimed to isolate the endemic Mmc strains in Hainan Island and reveal their molecular characteristics by genomic sequencing and comparative genomics to mitigate the impact of Mmc on local ruminant farming. Here, the Mmc HN-A strain was isolated and identified for the first time in Hainan Island, China. The genome of Mmc HN-A was sequenced. It contains a 1,084,691 bp-long circular chromosome and 848 coding genes. The genomic analysis of Mmc HN-A revealed 16 virulence factors, 2 gene islands, and a bacterial type IV secretion system protein VirD4. Comparative genomics showed that the core genome of the five Mycoplasma mycoides contained 611 genes that could be exploited to develop drugs and endemic vaccines. Additionally, 36 specific genes were included in the Mmc HN-A genome, which could provide the possibility for the further control and prevention of the Mmc effects on local ruminants and enrich the information on Mmc strains. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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11 pages, 2049 KiB  
Article
Molecular Typing Reveals Distinct Mycoplasma genitalium Transmission Networks among a Cohort of Men Who Have Sex with Men and a Cohort of Women in France
by Jennifer Guiraud, Marion Helary, Chloé Le Roy, Eric Elguero, Sabine Pereyre and Cécile Bébéar
Microorganisms 2022, 10(8), 1587; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10081587 - 06 Aug 2022
Cited by 5 | Viewed by 1800
Abstract
Mycoplasma genitalium causes sexually transmitted infecti.ons in men and women. Treatment failures to macrolides and fluoroquinolones have been reported worldwide. Although the mgpB typing method has often been used in M. genitalium-infected men who have sex with men (MSM), limited typing data [...] Read more.
Mycoplasma genitalium causes sexually transmitted infecti.ons in men and women. Treatment failures to macrolides and fluoroquinolones have been reported worldwide. Although the mgpB typing method has often been used in M. genitalium-infected men who have sex with men (MSM), limited typing data are available for M. genitalium-infected women. In this study, we aimed to investigate the genetic relationship between M. genitalium strains and their antibiotic resistance profile in a cohort of MSM (86.2% on HIV preexposure prophylaxis [PrEP], 13.8% HIV positive) and a large cohort of women using mgpB/MG309 typing. The mgpB types were determined in 374 samples from 305 women and 65 MSM. Three MSM and one woman had two concurrent or subsequent samples. Macrolide and fluoroquinolone resistance-associated mutations were searched in the 23S rRNA as well as parC and gyrA genes. The mgpB phylogenetic construction revealed three large clusters that differed according to sexual practices and geographical origin of patients. The prevalence of macrolide and fluoroquinolone resistance was significantly higher in MSM compared with women (95.4% vs. 14.1% and 30.6% vs. 7.2%, p < 0.001, respectively). The macrolide resistance spread was polyclonal in both populations, but clonal diffusion of two dual-resistant types was observed in PrEP users in association with high antibiotic pressure and dense connectivity in this population. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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24 pages, 5105 KiB  
Article
Heterologous Expression, Purification, and Immunomodulatory Effects of Recombinant Lipoprotein GUDIV-103 Isolated from Ureaplasma diversum
by Manoel Neres Santos-Junior, Wanderson Souza Neves, Ronaldo Silva Santos, Palloma Porto Almeida, Janaina Marinho Fernandes, Bruna Carolina de Brito Guimarães, Maysa Santos Barbosa, Lucas Santana Coelho da Silva, Camila Pacheco Gomes, Beatriz Almeida Sampaio, Izadora de Souza Rezende, Thiago Macedo Lopes Correia, Nayara Silva de Macedo Neres, Guilherme Barreto Campos, Bruno Lopes Bastos, Jorge Timenetsky and Lucas Miranda Marques
Microorganisms 2022, 10(5), 1032; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10051032 - 16 May 2022
Viewed by 2128
Abstract
Ureaplasma diversum is a bacterial pathogen that infects cattle and can cause severe inflammation of the genital and reproductive systems. Lipid-associated membrane proteins (LAMPs), including GUDIV-103, are the main virulence factors in this bacterium. In this study, we heterologously expressed recombinant GUDIV-103 (rGUDIV-103) [...] Read more.
Ureaplasma diversum is a bacterial pathogen that infects cattle and can cause severe inflammation of the genital and reproductive systems. Lipid-associated membrane proteins (LAMPs), including GUDIV-103, are the main virulence factors in this bacterium. In this study, we heterologously expressed recombinant GUDIV-103 (rGUDIV-103) in Escherichia coli, purified it, and evaluated its immunological reactivity and immunomodulatory effects in bovine peripheral blood mononuclear cells (PBMCs). Samples from rabbits inoculated with purified rGUDIV-103 were analysed using indirect enzyme-linked immunosorbent assay and dot blotting to confirm polyclonal antibody production and assess kinetics, respectively. The expression of this lipoprotein in field isolates was confirmed via Western blotting with anti-rGUDIV-103 serum and hydrophobic or hydrophilic proteins from 42 U. diversum strains. Moreover, the antibodies produced against the U. diversum ATCC 49783 strain recognised rGUDIV-103. The mitogenic potential of rGUDIV-103 was evaluated using a lymphoproliferation assay in 5(6)-carboxyfluorescein diacetate succinimidyl ester–labelled bovine PBMCs, where it induced lymphocyte proliferation. Quantitative polymerase chain reaction analysis revealed that the expression of interleukin-1β, toll-like receptor (TLR)-α, TLR2, TLR4, inducible nitric oxide synthase, and caspase-3–encoding genes increased more in rGUDIV-103–treated PBMCs than in untreated cells (p < 0.05). Treating PBMCs with rGUDIV-103 increased nitric oxide and hydrogen peroxide levels. The antigenic and immunogenic properties of rGUDIV-103 suggested its suitability for immunobiological application. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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20 pages, 2725 KiB  
Article
Sheep Infection Trials with ‘Phase-Locked’ Vpma Expression Variants of Mycoplasma agalactiae—Towards Elucidating the Role of a Multigene Family Encoding Variable Surface Lipoproteins in Infection and Disease
by Rohini Chopra-Dewasthaly, Andreas Dagn, Christian Lohinger, René Brunthaler, Martina Flöck, Munkhtsetseg Kargl, Shrilakshmi Hegde, Joachim Spergser and Renate Rosengarten
Microorganisms 2022, 10(4), 815; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10040815 - 14 Apr 2022
Cited by 1 | Viewed by 1647
Abstract
The significance of large multigene families causing high-frequency surface variations in mycoplasmas is not well-understood. Previously, VpmaY and VpmaU clonal variants of the Vpma family of lipoproteins of M. agalactiae were compared via experimental sheep infections using the two corresponding ‘Phase-Locked Mutants’. However, [...] Read more.
The significance of large multigene families causing high-frequency surface variations in mycoplasmas is not well-understood. Previously, VpmaY and VpmaU clonal variants of the Vpma family of lipoproteins of M. agalactiae were compared via experimental sheep infections using the two corresponding ‘Phase-Locked Mutants’. However, nothing is known about the infectivity of the remaining four Vpma expression variants VpmaX, VpmaW, VpmaZ and VpmaV as they were never evaluated in vivo. Here, in vivo infection and disease progression of all six Vpma expressers constituting the Vpma family of type strain PG2 were compared using the corresponding xer1-disrupted PLMs expressing single well-characterized Vpmas. Each of the six PLMs were separately evaluated using the intramammary sheep infection model along with the control phase-variable wildtype strain PG2. Thorough bacteriological, pathological and clinical examinations were performed, including assessment of milk quality, quantity and somatic cell counts. Altogether, the results indicated that the inability to vary the Vpma expression phase does not hamper the initiation of infection leading to mastitis for all six PLMs, except for PLMU, which showed a defect in host colonization and multiplication for the first 24 h p.i. and pathological/bacteriological analysis indicated a higher potential for systemic spread for PLMV and PLMX. This is the first study in which all isogenic expression variants of a large mycoplasma multigene family are tested in the natural host. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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Review

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21 pages, 403 KiB  
Review
Atypical Pathogens in Adult Community-Acquired Pneumonia and Implications for Empiric Antibiotic Treatment: A Narrative Review
by Nicolas Garin, Christophe Marti, Aicha Skali Lami and Virginie Prendki
Microorganisms 2022, 10(12), 2326; https://0-doi-org.brum.beds.ac.uk/10.3390/microorganisms10122326 - 24 Nov 2022
Cited by 7 | Viewed by 3877
Abstract
Atypical pathogens are intracellular bacteria causing community-acquired pneumonia (CAP) in a significant minority of patients. Legionella spp., Chlamydia pneumoniae and psittaci, Mycoplasma pneumoniae, and Coxiella burnetii are commonly included in this category. M. pneumoniae is present in 5–8% of CAP, being [...] Read more.
Atypical pathogens are intracellular bacteria causing community-acquired pneumonia (CAP) in a significant minority of patients. Legionella spp., Chlamydia pneumoniae and psittaci, Mycoplasma pneumoniae, and Coxiella burnetii are commonly included in this category. M. pneumoniae is present in 5–8% of CAP, being the second most frequent pathogen after Streptococcus pneumoniae. Legionella pneumophila is found in 3–5% of inpatients. Chlamydia spp. and Coxiella burnetii are present in less than 1% of patients. Legionella longbeachae is relatively frequent in New Zealand and Australia and might also be present in other parts of the world. Uncertainty remains on the prevalence of atypical pathogens, due to limitations in diagnostic means and methodological issues in epidemiological studies. Despite differences between CAP caused by typical and atypical pathogens, the clinical presentation alone does not allow accurate discrimination. Hence, antibiotics active against atypical pathogens (macrolides, tetracyclines and fluoroquinolones) should be included in the empiric antibiotic treatment of all patients with severe CAP. For patients with milder disease, evidence is lacking and recommendations differ between guidelines. Use of clinical prediction rules to identify patients most likely to be infected with atypical pathogens, and strategies of narrowing the antibiotic spectrum according to initial microbiologic investigations, should be the focus of future investigations. Full article
(This article belongs to the Special Issue Mycoplasma Pathogenicity, Persistence and Virulence)
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