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Current Opinion in Infectious Diseases Jun 2019To relate genomic changes to phenotypic adaptation and evolution from environmental bacteria to obligate human pathogens, focusing on the examples within Bordetella... (Review)
Review
PURPOSE OF REVIEW
To relate genomic changes to phenotypic adaptation and evolution from environmental bacteria to obligate human pathogens, focusing on the examples within Bordetella species.
RECENT FINDINGS
Recent studies showed that animal-pathogenic and human-pathogenic Bordetella species evolved from environmental ancestors in soil. The animal-pathogenic Bordetella bronchiseptica can hijack the life cycle of the soil-living amoeba Dictyostelium discoideum, surviving inside single-celled trophozoites, translocating to the fruiting bodies and disseminating along with amoeba spores. The association with amoeba may have been a 'training ground' for bacteria during the evolution to pathogens. Adaptation to an animal-associated life style was characterized by decreasing metabolic versatility and genome size and by acquisition of 'virulence factors' mediating the interaction with the new animal hosts. Subsequent emergence of human-specific pathogens, such as Bordetella pertussis from zoonoses of broader host range progenitors, was accompanied by a dramatic reduction in genome size, marked by the loss of hundreds of genes.
SUMMARY
The evolution of Bordetella from environmental microbes to animal-adapted and obligate human pathogens was accompanied by significant genome reduction with large-scale gene loss during divergence.
Topics: Adaptation, Biological; Adaptation, Physiological; Animals; Biological Evolution; Bordetella bronchiseptica; Bordetella pertussis; Host-Pathogen Interactions; Humans; Soil Microbiology
PubMed: 30921085
DOI: 10.1097/QCO.0000000000000549 -
Proceedings of the National Academy of... Oct 2023The pathogenic bacteria and cause pertussis (whooping cough) and pertussis-like disease, respectively, both of which are characterized by paroxysmal coughing. We...
The pathogenic bacteria and cause pertussis (whooping cough) and pertussis-like disease, respectively, both of which are characterized by paroxysmal coughing. We previously reported that pertussis toxin (PTx), which inactivates heterotrimeric GTPases of the G family through ADP-ribosylation of their α subunits, causes coughing in combination with Vag8 and lipid A in infection. In contrast, the mechanism of cough induced by , which produces Vag8 and lipopolysaccharide (LPS) containing lipid A, but not PTx, remained to be elucidated. Here, we show that a toxin we named deacylating autotransporter toxin (DAT) of inactivates heterotrimeric G GTPases through demyristoylation of their α subunits and contributes to cough production along with Vag8 and LPS. These results indicate that DAT plays a role in infection in place of PTx.
Topics: Humans; Bordetella parapertussis; Whooping Cough; Type V Secretion Systems; Cough; Lipid A; Lipopolysaccharides; Bordetella pertussis; Pertussis Toxin; Toxins, Biological
PubMed: 37748060
DOI: 10.1073/pnas.2308260120 -
Emerging Microbes & Infections Dec 2023causes pertussis (or whooping cough), a severe respiratory infectious disease in infants, although it can be prevented by whole cell and acellular vaccines. The recent...
causes pertussis (or whooping cough), a severe respiratory infectious disease in infants, although it can be prevented by whole cell and acellular vaccines. The recent pertussis resurgence in industrialised countries is partly attributed to pathogen adaptation to vaccines, while emergence of antimicrobial resistance, specifically to macrolides in China, has become a concern. Surveillance of current circulating and emerging strains is therefore vital to understand the risks they pose to public health. Although the use of genomics-based typing is increasing a genomic nomenclature for this pathogen has not been well established. Here, we implemented the multilevel genome typing (MGT) system for with five levels of resolution, which provide targeted typing of relevant lineages and discrimination of closely related strains at the finest scale. The lower resolution levels (MGT2 and MGT3) describe the distribution of major vaccine antigen alleles including , and as well as temporal and spatial trends within the global population. Mid-resolution levels (MGT3 and MGT4) enable typing of antibiotic-resistant lineages and Prn deficient lineages within the clade. The high-resolution level (MGT5) can capture finer-scale epidemiology such as outbreaks and local transmission events, with comparable resolution to existing genomic methods of strain-relatedness assessment. The scheme offers stable MGT-type assignments aiding harmonisation of typing and communication between laboratories. The scheme is available at https://mgtdb.unsw.edu.au/pertussis, is regularly updated from global data repositories and accepts public submissions. The MGT scheme provides a comprehensive, robust, and scalable system for global surveillance of .
Topics: Infant; Humans; Bordetella pertussis; Whooping Cough; Pertussis Vaccine; Genomics; Whole Genome Sequencing
PubMed: 37483082
DOI: 10.1080/22221751.2023.2239945 -
Microbiological Research Oct 2022Bacteria belonging to the genus Achromobacter are widely distributed in natural environments and have been recognized as emerging pathogens for their contribution to a... (Review)
Review
Bacteria belonging to the genus Achromobacter are widely distributed in natural environments and have been recognized as emerging pathogens for their contribution to a wide range of human infections. In particular, patients with cystic fibrosis (CF) are the subjects most frequently colonized by Achromobacter spp., which can cause persistent infections in their respiratory tract. Although many clinical aspects and pathogenic mechanisms still remain to be elucidated, Achromobacter spp. have been a source of expanding interest in recent years. This review examines the current literature regarding Achromobacter spp. role in CF, focusing on taxonomy, prevalence in CF lung infections, genomic characteristics, and adaptation strategies including modifications of metabolism and virulence, acquisition of antibiotic resistance, exchange of mobile genetic elements and development of hypermutation.
Topics: Achromobacter; Achromobacter denitrificans; Cystic Fibrosis; Gram-Negative Bacterial Infections; Humans; Lung; Prevalence
PubMed: 35931003
DOI: 10.1016/j.micres.2022.127140 -
Microbiology Spectrum Apr 2022Achromobacter denitrificans is an environmental opportunistic pathogen that is infecting a large number of immunocompromised patients. A more recently identified strain...
Achromobacter denitrificans is an environmental opportunistic pathogen that is infecting a large number of immunocompromised patients. A more recently identified strain from the historical collection of strains of Achromobacter denitrificans is Achromobacter mucicolens. In hosts with a variety of underlying diseases, spp. can induce a wide spectrum of disorders. Because of the bacterium's intrinsic genetic constitution and resistance gained over time, antibiotics are challenged to handle Due to the fact that is rare and its taxonomy is not completely understood, it is difficult to define clinical symptoms, acquisition risk factors, and thus the best therapeutic course of action. To help comprehend this intrinsic and acquired resistance, we analyzed the entire genome of the strain and utilized bioinformatics methods to estimate the strain's probable drug resistance profile. In our study, we have isolated and cultured a clinically important strain and subjected it to antimicrobial susceptibility tests against antibiotics in the Vitek 2 testing system. The strain's genome sequence as well as an investigation of 27 of its phenotypic traits provides important information regarding this pathogen. The genome of this strain possesses a number of antibiotic resistance genes that code for efflux pump systems and other antibiotic-regulating as well as -modifying enzymes. Our research analysis predicted genes involved in drug resistance, including genes for efflux pump systems, antibiotic efflux, antibiotic inactivation, and antibiotic target alteration. studies validated the genomic evidence for its ability to exhibit resistance against a wide range of antibiotics. Our investigation paves the way for more research on understanding the functioning of the key discovered genes that contribute toward the pathogenicity of and hence gives new information and treatment options for this emerging pathogen. species are well-known opportunistic human pathogens that can be found in water and soil and most commonly in hospital settings. They thrive in immunocompromised individuals, producing sporadic cases of pneumonia, septicemia, peritonitis, urinary tract infections, and other illnesses. strains are inherently resistant to a wide spectrum of antibiotics, making them difficult to treat promptly. The strain under study, , was notably resistant to various antibiotics, and the infection could be controlled only after several rounds of prescription medications at different doses. This consumed a lot of time and put the already immunosuppressed leukemic patient through a great ordeal. The study aimed to raise awareness about the importance of the bacterium's lethality, and doctors should evaluate the bacterium's potential for resistance before prescribing antibiotics. Sanitation and other precautions should also be implemented in hospitals and other public places.
Topics: Achromobacter; Achromobacter denitrificans; Anti-Bacterial Agents; Drug Resistance, Microbial; Genomics; Humans; Microbial Sensitivity Tests
PubMed: 35377213
DOI: 10.1128/spectrum.01916-21 -
BMC Infectious Diseases Aug 2021Bordetella avium, an aerobic bacterium that rarely causes infection in humans, is a species of Bordetella that generally inhabits the respiratory tracts of turkeys and...
BACKGROUND
Bordetella avium, an aerobic bacterium that rarely causes infection in humans, is a species of Bordetella that generally inhabits the respiratory tracts of turkeys and other birds. It causes a highly contagious bordetellosis. Few reports describe B. avium as a causative agent of eye-related infections.
CASE PRESENTATION
We report a case of acute infectious endophthalmitis associated with infection by B. avium after open trauma. After emergency vitrectomy and subsequent broad-spectrum antibiotic treatment, the infection was controlled successfully, and the patient's vision improved.
CONCLUSIONS
B. avium can cause infection in the human eye, which can manifest as acute purulent endophthalmitis. Nanopore targeted sequencing technology can quickly identify this organism. Emergency vitrectomy combined with lens removal and silicone oil tamponade and the early application of broad-spectrum antibiotics are key for successful treatment.
Topics: Bordetella; Bordetella avium; Cataract Extraction; Endophthalmitis; Humans; Vitrectomy
PubMed: 34412580
DOI: 10.1186/s12879-021-06546-1 -
Emerging Infectious Diseases Jun 2021Recent reemergence of pertussis (whooping cough) in highly vaccinated populations and rapid expansion of Bordetella pertussis strains lacking pertactin (PRN), a common... (Review)
Review
Recent reemergence of pertussis (whooping cough) in highly vaccinated populations and rapid expansion of Bordetella pertussis strains lacking pertactin (PRN), a common acellular vaccine antigen, have raised the specter of vaccine-driven evolution and potential return of what was once the major killer of children. The discovery that most circulating B. pertussis strains in the United States have acquired new and independent disruptive mutations in PRN is compelling evidence of strong selective pressure. However, the other 4 antigens included in acellular vaccines do not appear to be selected against so rapidly. We consider 3 aspects of PRN that distinguish it from other vaccine antigens, which might, individually or collectively, explain why only this antigen is being precipitously eliminated. An understanding of the increase in PRN-deficient strains should provide useful information for the current search for new protective antigens and provide broader lessons for the design of improved subunit vaccines.
Topics: Bacterial Outer Membrane Proteins; Bordetella pertussis; Child; Humans; Pertussis Vaccine; Virulence Factors, Bordetella; Whooping Cough
PubMed: 34014152
DOI: 10.3201/eid2706.203850 -
BMC Infectious Diseases Nov 2020Alcaligenes faecalis is usually causes opportunistic infections in humans. Alcaligenes faecalis infection is often difficult to treat due to its increased resistance to...
BACKGROUND
Alcaligenes faecalis is usually causes opportunistic infections in humans. Alcaligenes faecalis infection is often difficult to treat due to its increased resistance to several antibiotics. The results from a clinical study of patients with Alcaligenes faecalis infection may help improve patients' clinical care.
METHODS
We conducted a retrospective analysis of all patients presenting with Alcaligenes faecalis infection from January 2014 to December 2019. The medical records of all patients were reviewed for demographic information, clinical symptoms and signs, comorbidities, use of intravenous antibiotics within the past three months, bacterial culture, antibiotics sensitivity test, and clinical outcomes.
RESULTS
Sixty-one cases of Alcaligenes faecalis infection were seen during the study period, including 25 cases of cystitis, nine cases of diabetic foot infection, eight cases of pneumonia, seven cases of acute pyelonephritis, three cases of bacteremia, and nine cases of infection at specific sites. Thirty-seven patients (60.7%) had a history of receiving intravenous antibiotics within three months of the diagnosis. Fifty-one (83.6%) cases were mixed with other bacterial infections. Extensively drug-resistant infections have been reported since 2018. The best sensitivity rate to Alcaligenes faecalis was 66.7% for three antibiotics (imipenem, meropenem, and ceftazidime) in 2019. Two antibiotics (ciprofloxacin and piperacillin/tazobactam) sensitivity rates to A. faecalis were less than 50%.
CONCLUSIONS
The most frequent Alcaligenes faecalis infection sites, in order, are the bloodstream, urinary tract, skin and soft tissue, and middle ear. The susceptibility rate of Alcaligenes faecalis to commonly used antibiotics is decreasing. Extensively drug-resistant Alcaligenes faecalis infections have emerged.
Topics: Adult; Aged; Aged, 80 and over; Alcaligenes faecalis; Anti-Bacterial Agents; Bacteremia; Ceftazidime; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacterial Infections; Humans; Imipenem; Male; Meropenem; Microbial Sensitivity Tests; Middle Aged; Retrospective Studies; Treatment Outcome
PubMed: 33176714
DOI: 10.1186/s12879-020-05557-8 -
MBio Jun 2022What causes the cough in whooping cough (pertussis) has been a longstanding question in the field but has been difficult to answer because of the perceived lack of...
What causes the cough in whooping cough (pertussis) has been a longstanding question in the field but has been difficult to answer because of the perceived lack of convenient small animal models. Y. Hiramatsu, K. Suzuki, T. Nishida, N. Onoda, et al. (mBio 13:e01397-21, 2022, https://doi.org/10.1128/mbio.03197-21) used a mouse model and cellular studies to investigate bacterial and host factors that contribute to cough production during Bordetella pertussis infection. In elegant studies, they found that the bacterial factors pertussis toxin, lipooligosaccharide, and Vag8 function cooperatively to produce cough. These factors induce production of host bradykinin, a known cough inducer that sensitizes the ion channel TRPV1 on neurons, and they investigated host signaling pathways altered by the bacterial factors that exacerbate cough responses. This is a highly significant and important finding that not only elucidates mechanisms underlying the pathophysiology of the severe cough, but also may reveal potential novel therapeutic approaches to treat individuals suffering from the debilitating effects of cough in pertussis.
Topics: Animals; Bordetella Infections; Bordetella pertussis; Cough; Mice; Whooping Cough
PubMed: 35604095
DOI: 10.1128/mbio.00917-22 -
Characterization of Temperate LPS-Binding Bordetella avium Phages That Lack Superinfection Immunity.Microbiology Spectrum Jun 2023Bordetella avium causes a highly infectious upper respiratory tract disease in turkeys and other poultry with high economic losses. Considering the antimicrobial...
Bordetella avium causes a highly infectious upper respiratory tract disease in turkeys and other poultry with high economic losses. Considering the antimicrobial resistance crisis, bacteriophages (phages) may be an alternative approach for treating bacterial infections such as bordetellosis. Here, we describe seven phages, isolated from drinking water and feces from chicken and turkey farms. They showed strong bacteriolytic activity with a broad host range and used lipopolysaccharides (LPS) as a host receptor for their adsorption. All phages are myoviruses based on their structure observed by transmission electron microscopy. Genome sequence analyses revealed genome assembly sizes ranging from 39,087 to 43,144 bp. Their permutated genomes were organized colinearly, with a conserved module order, and were packed according to a predicted headful packing strategy. Notably, they contained genes encoding putative markers of lysogeny, indicative of temperate phages, despite their lytic phenotype. Further investigation revealed that the phages could indeed undergo a lysogenic life cycle with varying frequency. However, the lysogenic bacteria were still susceptible to superinfection with the same phages. This lack of stable superinfection immunity after lysogenization appears to be a characteristic feature of phages, which is favorable in terms of a potential therapeutic use of phages for the treatment of avian bordetellosis. To maintain the effectiveness of antibiotics over the long term, alternatives to treat infectious diseases are urgently needed. Therefore, phages have recently come back into focus as they can specifically infect and lyse bacteria and are naturally occurring. However, there is little information on phages that can infect pathogenic bacteria from animals, such as the causative agent of bordetellosis of poultry, . Therefore, in this study, phages were isolated and comprehensively characterized, including whole-genome analysis. Although phenotypically the phages were thought to undergo a lytic cycle, we demonstrated that they undergo a lysogenic phase, but that infection does not confer stable host superinfection immunity. These findings provide important information that could be relevant for potential biocontrol of avian bordetellosis by using phage therapy.
Topics: Animals; Bacteriophages; Lipopolysaccharides; Bordetella avium; Superinfection; Lysogeny; Bordetella Infections; Bacteria
PubMed: 37125905
DOI: 10.1128/spectrum.03702-22