Bordetella petrii clinical isolate

Evolution and Conservation of Bordetella Intracellular Survival in Eukaryotic Host Cells

The classical bordetellae possess several partially characterized virulence mechanisms that are studied in the context of a complete extracellular life cycle in their mammalian hosts. Yet, classical bordetellae have repeatedly been reported within dendritic cells (DCs) and alveolar macrophages in clinical samples, and in vitro experiments convincingly demonstrate that the bacteria can survive intracellularly within mammalian phagocytic cells, an ability that appears to have descended from ancestral progenitor species that lived in the environment and acquired the mechanisms to resist unicellular phagocytic predators. Many pathogens, including Mycobacterium tuberculosis, Salmonella enterica, Francisella tularensis, and Legionella pneumophila, are known to parasitize and multiply inside eukaryotic host cells. This strategy provides protection, nutrients, and the ability to disseminate systemically. While some work has been dedicated at characterizing intracellular survival of Bordetella pertussis, there is limited understanding of how this strategy has evolved within the genus Bordetella and the contributions of this ability to bacterial pathogenicity, evasion of host immunity as well as within and between-host dissemination. Here, we explore the mechanisms that control the metabolic changes accompanying intracellular survival and how these have been acquired and conserved throughout the evolutionary history of the Bordetella genus and discuss the possible implications of this strategy in the persistence and reemergence of B. pertussis in recent years.

Bordetella Type III Secretion Injectosome and Effector Proteins

Pertussis, also known as whooping cough, is a resurging acute respiratory disease of humans primarily caused by the Gram-negative coccobacilli Bordetella pertussis, and less commonly by the human-adapted lineage of B. parapertussis _HU. The ovine-adapted lineage of B. parapertussis _OV infects only sheep, while B. bronchiseptica causes chronic and often asymptomatic respiratory infections in a broad range of mammals but rarely in humans. A largely overlapping set of virulence factors inflicts the pathogenicity of these bordetellae. Their genomes also harbor a pathogenicity island, named bsc locus, that encodes components of the type III secretion injectosome, and adjacent btr locus with the type III regulatory proteins. The Bsc injectosome of bordetellae translocates the cytotoxic BteA effector protein, also referred to as BopC, into the cells of the mammalian hosts. While the role of type III secretion activity in the persistent colonization of the lower respiratory tract by B. bronchiseptica is well recognized, the functionality of the type III secretion injectosome in B. pertussis was overlooked for many years due to the adaptation of laboratory-passaged B. pertussis strains. This review highlights the current knowledge of the type III secretion system in the so-called classical Bordetella species, comprising B. pertussis, B. parapertussis, and B. bronchiseptica, and discusses its functional divergence. Comparison with other well-studied bacterial injectosomes, regulation of the type III secretion on the transcriptional and post-transcriptional level, and activities of BteA effector protein and BopN protein, homologous to the type III secretion gatekeepers, are addressed.

Evolution of Bordetellae from Environmental Microbes to Human Respiratory Pathogens: Amoebae as a Missing Link

The genus Bordetella comprises several bacterial species that colonize the respiratory tract of mammals. It includes B. pertussis, a human-restricted pathogen that is the causative agent of Whooping Cough. In contrast, the closely related species B. bronchiseptica colonizes a broad range of animals as well as immunocompromised humans. Recent metagenomic studies have identified known and novel bordetellae isolated from different environmental sources, providing a new perspective on their natural history. Using phylogenetic analysis, we have shown that human and animal pathogenic bordetellae have most likely evolved from ancestors that originated from soil and water. Our recent study found that B. bronchiseptica can evade amoebic predation and utilize Dictyostelium discoideum as an expansion and transmission vector, which suggests that the evolutionary pressure to evade the amoebic predator enabled the rise of bordetellae as respiratory pathogens. Interactions with amoeba may represent the starting point for bacterial adaptation to eukaryotic cells. However, as bacteria evolve and adapt to a novel host, they can become specialized and restricted to a specific host. B. pertussis is known to colonize and cause infection only in humans, and this specialization to a closed human-to-human lifecycle has involved genome reduction and the loss of ability to utilize amoeba as an environmental reservoir. The discoveries from studying the interaction of Bordetella species with amoeba will elicit a better understanding of the evolutionary history of these and other important human pathogens.

Environmental Origin of the Genus Bordetella

Members of the genus Bordetella include human and animal pathogens that cause a variety of respiratory infections, including whooping cough in humans. Despite the long known ability to switch between a within-animal and an extra-host lifestyle under laboratory growth conditions, no extra-host niches of pathogenic Bordetella species have been defined. To better understand the distribution of Bordetella species in the environment, we probed the NCBI nucleotide database with the 16S ribosomal RNA (16S rRNA) gene sequences from pathogenic Bordetella species. Bacteria of the genus Bordetella were frequently found in soil, water, sediment, and plants. Phylogenetic analyses of their 16S rRNA gene sequences showed that Bordetella recovered from environmental samples are evolutionarily ancestral to animal-associated species. Sequences from environmental samples had a significantly higher genetic diversity, were located closer to the root of the phylogenetic tree and were present in all 10 identified sequence clades, while only four sequence clades possessed animal-associated species. The pathogenic bordetellae appear to have evolved from ancestors in soil and/or water. We show that, despite being animal-adapted pathogens, Bordetella bronchiseptica, and Bordetella hinzii have preserved the ability to grow and proliferate in soil. Our data implicate soil as a probable environmental origin of Bordetella species, including the animal-pathogenic lineages. Soil may further constitute an environmental niche, allowing for persistence and dissemination of the bacterial pathogens. Spread of pathogenic bordetellae from an environmental reservoir such as soil may potentially explain their wide distribution as well as frequent disease outbreaks that start without an obvious infectious source.

Drug Target Identification and Elucidation of Natural Inhibitors for Bordetella petrii: An In Silico Study

Environmental microbes like Bordetella petrii has been established as a causative agent for various infectious diseases in human. Again, development of drug resistance in B. petrii challenged to combat against the infection. Identification of potential drug target and proposing a novel lead compound against the pathogen has a great aid and value. In this study, bioinformatics tools and technology have been applied to suggest a potential drug target by screening the proteome information of B. petrii DSM 12804 (accession No. PRJNA28135) from genome database of National Centre for Biotechnology information. In this regards, the inhibitory effect of nine natural compounds like ajoene (Allium sativum), allicin (A. sativum), cinnamaldehyde (Cinnamomum cassia), curcumin (Curcuma longa), gallotannin (active component of green tea and red wine), isoorientin (Anthopterus wardii), isovitexin (A. wardii), neral (Melissa officinalis), and vitexin (A. wardii) have been acknowledged with anti-bacterial properties and hence tested against identified drug target of B. petrii by implicating computational approach. The in silico studies revealed the hypothesis that lpxD could be a potential drug target and with recommendation of a strong inhibitory effect of selected natural compounds against infection caused due to B. petrii, would be further validated through in vitro experiments.

Acquisition and loss of virulence-associated factors during genome evolution and speciation in three clades of Bordetella species

Background

The genus Bordetella consists of nine species that include important respiratory pathogens such as the ‘classical’ species B. bronchiseptica, B. pertussis and B. parapertussis and six more distantly related and less extensively studied species. Here we analyze sequence diversity and gene content of 128 genome sequences from all nine species with focus on the evolution of virulence-associated factors.

Results

Both genome-wide sequence-based and gene content-based phylogenetic trees divide the genus into three species clades. The phylogenies are congruent between species suggesting genus-wide co-evolution of sequence diversity and gene content, but less correlated within species, mainly because of strain-specific presence of many different prophages. We compared the genomes with focus on virulence-associated genes and identified multiple clade-specific, species-specific and strain-specific events of gene acquisition and gene loss, including genes encoding O-antigens, protein secretion systems and bacterial toxins. Gene loss was more frequent than gene gain throughout the evolution, and loss of hundreds of genes was associated with the origin of several species, including the recently evolved human-restricted B. pertussis and B. holmesii, B. parapertussis and the avian pathogen B. avium.

Conclusions

Acquisition and loss of multiple genes drive the evolution and speciation in the genus Bordetella, including large scale gene loss associated with the origin of several species. Recent loss and functional inactivation of genes, including those encoding pertussis vaccine components and bacterial toxins, in individual strains emphasize ongoing evolution.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-016-3112-5) contains supplementary material, which is available to authorized users.

Novel environmental species isolated from the plaster wall surface of mural paintings in the Takamatsuzuka tumulus: Bordetella muralis sp. nov., Bordetella tumulicola sp. nov. and Bordetella tumbae sp. nov

Ten strains of Gram-stain-negative, non-spore-forming, non-motile coccobacilli were isolated from the plaster wall surface of 1300-year-old mural paintings inside the stone chamber of the Takamatsuzuka tumulus in Asuka village (Asuka-mura), Nara Prefecture, Japan. Based on 16S rRNA gene sequence analysis of the isolates, they belonged to the proteobacterial genus Bordetella (class Betaproteobacteria) and could be separated into three groups representing novel lineages within the genus Bordetella. Three isolates were selected, one from each group, and identified carefully using a polyphasic approach. The isolates were characterized by the presence of Q-8 as their major ubiquinone system and C16 : 0 (30.0-41.8 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 10.1-27.0 %) and C17 : 0 cyclo (10.8-23.8 %) as the predominant fatty acids. The major hydroxy fatty acids were C12 : 0 2-OH and C14 : 0 2-OH. The DNA G+C content was 59.6-60.0 mol%. DNA-DNA hybridization tests confirmed that the isolates represented three separate novel species, for which the names Bordetella muralis sp. nov. (type strain T6220-3-2bT = JCM 30931T = NCIMB 15006T), Bordetella tumulicola sp. nov. (type strain T6517-1-4bT = JCM 30935T = NCIMB 15007T) and Bordetella tumbae sp. nov. (type strain T6713-1-3bT = JCM 30934T = NCIMB 15008T) are proposed. These results support previous evidence that members of the genus Bordetella exist in the environment and may be ubiquitous in soil and/or water.

Bordetella petrii recovered from chronic pansinusitis in an adult with cystic fibrosis

To date Bordetella petrii has infrequently been identified within the clinical setting likely due to the asaccharolytic nature of this organism. We present a case of B. petrii recovered on two separate events in a patient with adult cystic fibrosis experiencing chronic pansinusitis.

Septic arthritis and osteomyelitis due to Bordetella petrii

A case of Bordetella petrii septic arthritis and osteomyelitis in an elbow resulted from a dirt bike accident in Hawaii. Two months of intravenous antibiotics and repeated surgeries were required to cure this infection. Our case, and literature review, suggests that extended-spectrum penicillins, tetracycline, and trimethoprim-sulfamethoxazole are good treatment options.

Other Bordetellas, lessons for and from pertussis vaccines

The Bordetella genus comprises nine species of which Bordetella pertussis and B. parapertussis are isolated from humans and are the most studied Bordetella species since they cause whooping cough. They both originate from B. bronchiseptica, which infects several mammals and immune compromised humans, but the intensive use of pertussis vaccines induced changes in B. pertussis and B. parapertussis populations. B. petrii and B. holmesii are other species of unknown reservoir and transmission pattern that have been described in humans. It is still unknown whether these species are pathogens for humans or only opportunistic bacteria but biological diagnosis has confirmed the presence of B. holmesii in human respiratory samples while B. petrii and the four other species have little implications for public health.

Bordetella holmesii: an under-recognised Bordetella species

Bordetella holmesii, first described in 1995, is believed to cause both invasive infections (bacteraemia, meningitis, endocarditis, pericarditis, pneumonia, and arthritis) and pertussis-like symptoms. Infection with B holmesii is frequently misidentified as being with B pertussis, the cause of whooping cough, because routine diagnostic tests for pertussis are not species-specific. In this Review, we summarise knowledge about B holmesii diagnosis and treatment, and assess research needs. Although no fatal cases of B holmesii have been reported, associated invasive infections can cause substantial morbidities, even in previously healthy individuals. Antimicrobial treatment can be problematic because B holmesii's susceptibility to macrolides (used empirically to treat B pertussis) and third-generation cephalosporins (often used to treat invasive infections) is lower than would be expected. B holmesii's adaptation to human beings is continuing, and virulence might increase, causing the need for better diagnostic assays and epidemiological surveillance.

Adaptability and persistence of the emerging pathogen Bordetella petrii

The first described, environmentally isolated, Bordetella petrii was shown to undergo massive genomic rearrangements in vitro. More recently, B. petrii was isolated from clinical samples associated with jaw, ear bone, cystic fibrosis and chronic pulmonary disease. However, the in vivo consequences of B. petrii genome plasticity and its pathogenicity remain obscure. B. petrii was identified from four sequential respiratory samples and a post-mortem spleen sample of a woman presenting with bronchiectasis and cavitary lung disease associated with nontuberculous mycobacterial infection. Strains were compared genetically, phenotypically and by antibody recognition from the patient and from inoculated mice. The successive B. petrii strains exhibited differences in growth, antibiotic susceptibility and recognition by the patient’s antibodies. Antibodies from mice inoculated with these strains recapitulated the specificity and strain dependent response that was seen with the patient’s serum. Finally, we characterize one strain that was poorly recognized by the patient’s antibodies, due to a defect in the lipopolysaccharide O-antigen, and identify a mutation associated with this phenotype. We propose that B. petrii is remarkably adaptable in vivo, providing a possible connection between immune response and bacterial evasion and supporting infection persistence.

Isolation of Kerstersia gyiorum from a patient with cholesteatomatous chronic otitis media

We describe the first case of a Kerstersia gyiorum strain isolated from a patient with cholesteatomatous chronic otitis media. We emphasize the isolation of members of the family Alcaligenaceae in serious infections and unusual sites and the importance of polyphasic identification addressing the definitive identification.

Bordetella petrii infection with long-lasting persistence in human

B. petrii infection can persist in persons with chronic obstructive pulmonary disease.

We report the repeated isolation of Bordetella petrii in the sputum of a 79-year-old female patient with diffuse bronchiectasis and persistence of the bacterium for >1 year. The patient was first hospitalized due to dyspnea, which developed into severe cough with purulent sputum that yielded B. petrii on culture. After this first episode, the patient was hospitalized an additional 4 times with bronchorrhea symptoms. The isolates collected were analyzed by using biochemical, genotypic, and proteomic tools. Expression of specific proteins was analyzed by using serum samples from the patient. The B. petrii isolates were compared with other B. petrii isolates collected from humans or the environment and with isolates of B. pertussis, B. parapertussis, B. bronchiseptica, and B. holmesii, obtained from human respiratory tract infections. Our observations indicate that B. petrii can persist in persons with chronic pulmonary obstructive disease as has been previously demonstrated for B. bronchiseptica.

Bordetella holmesii bacteremia in asplenic children: report of four cases initially misidentified as Acinetobacter lwoffii

Bordetella holmesii is a fastidious Gram-negative rod that was initially identified in 1995. It causes bacteremia, predominantly among patients with anatomical or functional asplenia. We report four cases of B. holmesii bacteremia in asplenic children occurring within the last 4 years. In all cases, B. holmesii was misidentified by an automated system as Acinetobacter lwoffii.

The complete genome sequence of Cupriavidus metallidurans strain CH34, a master survivalist in harsh and anthropogenic environments

Many bacteria in the environment have adapted to the presence of toxic heavy metals. Over the last 30 years, this heavy metal tolerance was the subject of extensive research. The bacterium Cupriavidus metallidurans strain CH34, originally isolated by us in 1976 from a metal processing factory, is considered a major model organism in this field because it withstands milli-molar range concentrations of over 20 different heavy metal ions. This tolerance is mostly achieved by rapid ion efflux but also by metal-complexation and -reduction. We present here the full genome sequence of strain CH34 and the manual annotation of all its genes. The genome of C. metallidurans CH34 is composed of two large circular chromosomes CHR1 and CHR2 of, respectively, 3,928,089 bp and 2,580,084 bp, and two megaplasmids pMOL28 and pMOL30 of, respectively, 171,459 bp and 233,720 bp in size. At least 25 loci for heavy-metal resistance (HMR) are distributed over the four replicons. Approximately 67% of the 6,717 coding sequences (CDSs) present in the CH34 genome could be assigned a putative function, and 9.1% (611 genes) appear to be unique to this strain. One out of five proteins is associated with either transport or transcription while the relay of environmental stimuli is governed by more than 600 signal transduction systems. The CH34 genome is most similar to the genomes of other Cupriavidus strains by correspondence between the respective CHR1 replicons but also displays similarity to the genomes of more distantly related species as a result of gene transfer and through the presence of large genomic islands. The presence of at least 57 IS elements and 19 transposons and the ability to take in and express foreign genes indicates a very dynamic and complex genome shaped by evolutionary forces. The genome data show that C. metallidurans CH34 is particularly well equipped to live in extreme conditions and anthropogenic environments that are rich in metals.

Genomic island excisions in Bordetella petrii

Background

Among the members of the genus Bordetella B. petrii is unique, since it is the only species isolated from the environment, while the pathogenic Bordetellae are obligately associated with host organisms. Another feature distinguishing B. petrii from the other sequenced Bordetellae is the presence of a large number of mobile genetic elements including several large genomic regions with typical characteristics of genomic islands collectively known as integrative and conjugative elements (ICEs). These elements mainly encode accessory metabolic factors enabling this bacterium to grow on a large repertoire of aromatic compounds.

Results

During in vitro culture of Bordetella petrii colony variants appear frequently. We show that this variability can be attributed to the presence of a large number of metastable mobile genetic elements on its chromosome. In fact, the genome sequence of B. petrii revealed the presence of at least seven large genomic islands mostly encoding accessory metabolic functions involved in the degradation of aromatic compounds and detoxification of heavy metals. Four of these islands (termed GI1 to GI3 and GI6) are highly related to ICEclc of Pseudomonas knackmussii sp. strain B13. Here we present first data about the molecular characterization of these islands. We defined the exact borders of each island and we show that during standard culture of the bacteria these islands get excised from the chromosome. For all but one of these islands (GI5) we could detect circular intermediates. For the clc-like elements GI1 to GI3 of B. petrii we provide evidence that tandem insertion of these islands which all encode highly related integrases and attachment sites may also lead to incorporation of genomic DNA which originally was not part of the island and to the formation of huge composite islands. By integration of a tetracycline resistance cassette into GI3 we found this island to be rather unstable and to be lost from the bacterial population within about 100 consecutive generations. Furthermore, we show that GI3 is self transmissible and by conjugation can be transferred to B. bronchiseptica thus proving it to be an active integrative and conjugative element

Conclusion

The results show that phenotypic variation of B. petrii is correlated with the presence of genomic islands. Tandem integration of related islands may contribute to island evolution by the acquisition of genes originally belonging to the bacterial core genome. In conclusion, B. petrii appears to be the first member of the genus in which horizontal gene transfer events have massively shaped its genome structure.

The missing link: Bordetella petrii is endowed with both the metabolic versatility of environmental bacteria and virulence traits of pathogenic Bordetellae

BACKGROUND

Bordetella petrii is the only environmental species hitherto found among the otherwise host-restricted and pathogenic members of the genus Bordetella. Phylogenetically, it connects the pathogenic Bordetellae and environmental bacteria of the genera Achromobacter and Alcaligenes, which are opportunistic pathogens. B. petrii strains have been isolated from very different environmental niches, including river sediment, polluted soil, marine sponges and a grass root. Recently, clinical isolates associated with bone degenerative disease or cystic fibrosis have also been described.

RESULTS

In this manuscript we present the results of the analysis of the completely annotated genome sequence of the B. petrii strain DSMZ12804. B. petrii has a mosaic genome of 5,287,950 bp harboring numerous mobile genetic elements, including seven large genomic islands. Four of them are highly related to the clc element of Pseudomonas knackmussii B13, which encodes genes involved in the degradation of aromatics. Though being an environmental isolate, the sequenced B. petrii strain also encodes proteins related to virulence factors of the pathogenic Bordetellae, including the filamentous hemagglutinin, which is a major colonization factor of B. pertussis, and the master virulence regulator BvgAS. However, it lacks all known toxins of the pathogenic Bordetellae.

CONCLUSION

The genomic analysis suggests that B. petrii represents an evolutionary link between free-living environmental bacteria and the host-restricted obligate pathogenic Bordetellae. Its remarkable metabolic versatility may enable B. petrii to thrive in very different ecological niches.

Achromobacter xylosoxidans subsp. xylosoxidans prosthetic aortic valve infective endocarditis and aortic root abscesses

We report a case of prosthetic valve infective endocarditis and aortic root abscesses caused by Achromobacter xylosoxidans subsp. xylosoxidans. The patient was an intravenous drug user and had injected amphetamines using 'duck pond water' as a diluent. After surgical intervention and 6 weeks of intravenous meropenem therapy, the patient made an uneventful recovery.

A UK clinical isolate of Bordetella hinzii from a patient with myelodysplastic syndrome

What is believed to be the first clinical isolate of Bordetella hinzii in the UK, from a patient with myelodysplastic syndrome, is described. This patient had no known avian exposure, and the source of the organism remains unknown. It appears that the underlying immune deficiency of the patient increased the susceptibility to opportunistic infection with this organism. Human infection with B. hinzii is rare and this species is difficult to differentiate from Bordetella avium by routine phenotypic methods. Confirmation can be reliably achieved using genotypic methods, and the greater mutational variation of the ompA gene compared to other genes (e.g. 16S rRNA gene) allows unambiguous identification of this and other non-classical Bordetella species.

The first UK isolate of ‘Bordetella ansorpii’ from an immunocompromised patient

What is believed to be the first clinical isolate of ‘Bordetella ansorpii’ in the UK from an immunocompromised patient is described. The only previously documented isolation of ‘B. ansorpii’ was following the initial culture of a single strain from an epidermal cyst of a patient in Korea.

Bordetella petrii from a clinical sample in Australia: isolation and molecular identification

The first isolation of Bordetella petrii from a patient with chronic suppurative mastoiditis is reported. Molecular characterization of the isolate was performed by sequencing the small-subunit rRNA gene, the Bordetella outer-membrane protein A gene (ompA) and the RisA response regulator gene (risA). This is the first reported case of B. petrii causing suppurative mastoiditis and only the second documented case of a clinically significant B. petrii isolate.