Global transcriptome analysis of Stenotrophomonas maltophilia in response to growth at human body temperature

Stenotrophomonas maltophilia is a typical example of an environmental originated opportunistic human pathogen, which can thrive at different habitats including the human body and can cause a wide range of infections. It must cope with heat stress during transition from the environment to the human body as the physiological temperature of the human body (37 °C) is higher than environmental niches (22–30 °C). Interestingly, S. rhizophila a phylogenetic neighbour of S. maltophilia within genus Stenotrophomonas is unable to grow at 37 °C. Thus, it is crucial to understand how S. maltophilia is adapted to human body temperature, which could suggest its evolution as an opportunistic human pathogen. In this study, we have performed comparative transcriptome analysis of S. maltophilia grown at 28 and 37 °C as temperature representative for environmental niches and the human body, respectively. RNA-Seq analysis revealed several interesting findings showing alterations in gene-expression levels at 28 and 37 °C, which can play an important role during infection. We have observed downregulation of genes involved in cellular motility, energy production and metabolism, replication and repair whereas upregulation of VirB/D4 type IV secretion system, aerotaxis, cation diffusion facilitator family transporter and LacI family transcriptional regulators at 37 °C. Microscopy and plate assays corroborated altered expression of genes involved in motility. The results obtained enhance our understanding of the strategies employed by S. maltophilia during adaptation towards the human body.

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Complete Genome Sequence of Stenotrophomonas Phage Mendera

Microbiology Resource Announcements ◽

10.1128/mra.01411-19 ◽

2020 ◽

Vol 9 (1) ◽

Author(s):

Kameron D. Garza ◽

Heather Newkirk ◽

Russell Moreland ◽

Carlos F. Gonzalez ◽

Mei Liu ◽

...

Keyword(s):

Genome Sequence ◽

Complete Genome Sequence ◽

Complete Genome ◽

Stenotrophomonas Maltophilia ◽

Human Pathogen ◽

Base Pairs ◽

Content Type ◽

Genomic Annotation ◽

Opportunistic Human Pathogen

Stenotrophomonas maltophilia is an emerging opportunistic human pathogen. In this report, we describe the isolation and genomic annotation of the S. maltophilia-infecting bacteriophage Mendera. A myophage of 159,961 base pairs, Mendera is T4-like and related most closely to Stenotrophomonas phage IME-SM1.

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Stenotrophomonas maltophilia as a rare cause of meningitis and ventriculoperitoneal shunt infection

Access Microbiology ◽

10.1099/acmi.0.000266 ◽

2021 ◽

Vol 3 (10) ◽

Author(s):

Adarsh Manuel ◽

Akarsh Jayachandran ◽

Srinivasan Harish ◽

Thenozhi Sunil ◽

Vishnu Das K. R. ◽

...

Keyword(s):

Ventriculoperitoneal Shunt ◽

Stenotrophomonas Maltophilia ◽

Type Species ◽

Shunt Infection ◽

Young Female ◽

Shunt Revision ◽

Content Type ◽

Shunt Tube ◽

Link Type ◽

Ventriculoperitoneal Shunt Infection

Stenotrophomonas maltophilia is an extremely rare pathogen responsible for ventriculoperitoneal shunt infection and meningitis. This young female patient with history of multiple shunt revisions in the past, came to us with shunt dysfunction and exposure of the ventriculoperitoneal shunt tube in the neck. The abdominal end of the shunt tube was seen migrating into the bowel during shunt revision. The cerebrospinal fluid analysis showed evidence of Stenotrophomonas maltophilia growth. This is the first reported case of Stenotrophomonas maltophilia meningitis associated with ventriculoperitoneal shunt migration into the bowel.

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Stenotrophomonas maltophilia phenotypic and genotypic features through 4-year cystic fibrosis lung colonization

Journal of Medical Microbiology ◽

10.1099/jmm.0.001281 ◽

2020 ◽

Author(s):

Eliana Alcaraz ◽

Daniela Centrón ◽

Gabriela Camicia ◽

María Paula Quiroga ◽

José Di Conza ◽

...

Keyword(s):

Cystic Fibrosis ◽

Adult Patient ◽

Virulence Factors ◽

Stenotrophomonas Maltophilia ◽

Type Species ◽

Mutation Frequency ◽

Content Type ◽

Link Type ◽

Clonal Relatedness ◽

Over Time

Introduction. Stenotrophomonas maltophilia has emerged as one of the most common multi-drug-resistant pathogens isolated from people with cystic fibrosis (CF). However, its adaptation over time to CF lungs has not been fully established. Hypothesis. Sequential isolates of S. maltophilia from a Brazilian adult patient are clonally related and show a pattern of adaptation by loss of virulence factors. Aim. To investigate antimicrobial susceptibility, clonal relatedness, mutation frequency, quorum sensing (QS) and selected virulence factors in sequential S. maltophilia isolates from a Brazilian adult patient attending a CF referral centre in Buenos Aires, Argentina, between May 2014 and May 2018. Methodology. The antibiotic resistance of 11 S. maltophilia isolates recovered from expectorations of an adult female with CF was determined. Clonal relatedness, mutation frequency, QS variants (RpfC–RpfF), QS autoinducer (DSF) and virulence factors were investigated in eight viable isolates. Results. Seven S. maltophilia isolates were resistant to trimethoprim–sulfamethoxazole and five to levofloxacin. All isolates were susceptible to minocycline. Strong, weak and normomutators were detected, with a tendency to decreased mutation rate over time. XbaI PFGE revealed that seven isolates belong to two related clones. All isolates were RpfC–RpfF1 variants and DSF producers. Only two isolates produced weak biofilms, but none displayed swimming or twitching motility. Four isolates showed proteolytic activity and amplified stmPr1 and stmPr2 genes. Only the first three isolates were siderophore producers. Four isolates showed high resistance to oxidative stress, while the last four showed moderate resistance. Conclusion. The present study shows the long-time persistence of two related S. maltophilia clones in an adult female with CF. During the adaptation of the prevalent clones to the CF lungs over time, we identified a gradual loss of virulence factors that could be associated with the high amounts of DSF produced by the evolved isolates. Further, a decreased mutation rate was observed in the late isolates. The role of all these adaptations over time remains to be elucidated from a clinical perspective, probably focusing on the damage they can cause to CF lungs.

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Idification and structural characterisation of a catecholate-type siderophore produced by Stenotrophomonas maltophilia K279a

Microbiology ◽

10.1099/mic.0.001071 ◽

2021 ◽

Vol 167 (7) ◽

Author(s):

Atsushi Hisatomi ◽

Yuh Shiwa ◽

Nobuyuki Fujita ◽

Hiroyuki Koshino ◽

Naoto Tanaka

Keyword(s):

Stenotrophomonas Maltophilia ◽

Type Species ◽

Monomer Unit ◽

Reversed Phase ◽

Negative Bacterium ◽

Content Type ◽

Structural Characterisation ◽

Link Type ◽

Wide Range ◽

C Nmr

Siderophores are produced by several bacteria that utilise iron in various environments. Elucidating the structure of a specific siderophore may have valuable applications in drug development. Stenotrophomonas maltophilia , a Gram-negative bacterium that inhabits a wide range of environments and can cause pneumonia, produces siderophores. However, the structure was unknown, and therefore, in this study, we aimed to elucidate it. We purified siderophores from cultures of S. maltophilia K279a using preparative reversed-phase HPLC. The structure was analysed through LC-MS and 1H and 13C NMR. The results demonstrated that S. maltophilia K279a produces 2,3-dihydroxybenzoylserine (DHBS), a monomer unit of enterobactin. We suggested the uptake of Iron(III) by the DHBS complex. DHBS production by S. maltophilia K279a could be attributed to an incomplete enterobactin pathway. Drugs targeting DHBS synthesis could prevent S. maltophilia infection.

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Characterization of the φCTX-like Pseudomonas aeruginosa phage Dobby isolated from the kidney stone microbiota

Access Microbiology ◽

10.1099/acmi.0.000002 ◽

2019 ◽

Vol 1 (1) ◽

Cited By ~ 2

Author(s):

Genevieve Johnson ◽

Alan J. Wolfe ◽

Catherine Putonti

Keyword(s):

Pseudomonas Aeruginosa ◽

Urinary Tract ◽

Human Body ◽

Kidney Stone ◽

Type Species ◽

Phage Group ◽

Content Type ◽

Link Type ◽

Abundance And Diversity ◽

Cultured Bacteria

Bacteriophages (phages) are vital members of the human microbiota. They are abundant even within low biomass niches of the human body, including the lower urinary tract. While several prior studies have cultured bacteria from kidney stones, this is the first study to explore phages within the kidney stone microbiota. Here we report Dobby, a temperate phage isolated from a strain of Pseudomonas aeruginosa cultured from a kidney stone. Dobby is capable of lysing clinical P. aeruginosa strains within our collection from the urinary tract. Sequencing was performed producing a 37 152 bp genome that closely resembles the temperate P. aeruginosa phage φCTX, a member of the P2 phage group. Dobby does not, however, encode for the cytotoxin CTX. Dobby’s genome was queried against publicly available bacterial sequences identifying 44 other φCTX-like prophages. These prophages are integrated within the genomes of P. aeruginosa strains from a variety of environments, including strains isolated from urine samples and other niches of the human body. Phylogenetic analysis suggests that the temperate φCTX phage species is widespread. With the isolation of Dobby, we now have evidence that phages are members of the kidney stone microbiota. Further investigation, however, is needed to determine their abundance and diversity within these communities.

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A Unique Chromosomal Rearrangement in the Cryptococcus neoformans var. grubii Type Strain Enhances Key Phenotypes Associated with Virulence

mBio ◽

10.1128/mbio.00310-11 ◽

2012 ◽

Vol 3 (2) ◽

Cited By ~ 21

Author(s):

Carl A. Morrow ◽

I. Russel Lee ◽

Eve W. L. Chow ◽

Kate L. Ormerod ◽

Anita Goldinger ◽

...

Keyword(s):

Body Temperature ◽

Cryptococcus Neoformans ◽

Human Body ◽

Fungal Pathogen ◽

Type Strain ◽

Clinical Sample ◽

Disease Patient ◽

Sub Saharan Africa ◽

Content Type ◽

Human Body Temperature

ABSTRACTThe accumulation of genomic structural variation between closely related populations over time can lead to reproductive isolation and speciation. The fungal pathogenCryptococcusis thought to have recently diversified, forming a species complex containing members with distinct morphologies, distributions, and pathologies of infection. We have investigated structural changes in genomic architecture such as inversions and translocations that distinguish the most pathogenic variety,Cryptococcus neoformansvar.grubii, from the less clinically prevalentCryptococcus neoformansvar.neoformansandCryptococcus gattii. Synteny analysis between the genomes of the threeCryptococcusspecies/varieties (strains H99, JEC21, and R265) reveals thatC. neoformansvar.grubiipossesses surprisingly few unique genomic rearrangements. All but one are relatively small and are shared by all molecular subtypes ofC. neoformansvar.grubii. In contrast, the large translocation peculiar to theC. neoformansvar.grubiitype strain is found in all tested subcultures from multiple laboratories, suggesting that it has possessed this rearrangement since its isolation from a human clinical sample. Furthermore, we find that the translocation directly disrupts two genes. The first of these encodes a novel protein involved in metabolism of glucose at human body temperature and affects intracellular levels of trehalose. The second encodes a homeodomain-containing transcription factor that modulates melanin production. Both mutations would be predicted to increase pathogenicity; however, when recreated in an alternate genetic background, these mutations do not affect virulence in animal models. The type strain ofC. neoformansvar.grubiiin which the majority of molecular studies have been performed is therefore atypical for carbon metabolism and key virulence attributes.IMPORTANCEThe fungal pathogenCryptococcusis a major cause of mortality among the immunocompromised population, primarily in AIDS patients of sub-Saharan Africa. Most research into the particular variety ofCryptococcusresponsible for the vast majority of infections,Cryptococcus neoformansvar.grubii, is performed using the type strain isolated in 1978 from a Hodgkin’s disease patient from North Carolina. We have determined that this particular isolate contains a chromosomal translocation that directly interrupts two genes, which all descendants of this strain from various research laboratories appear to possess. Disruption of these two genes affects multiple virulence factors ofCryptococcus, particularly the ability to grow at human body temperature, which could have wide-ranging implications for molecular genetic studies and virulence assays using this important strain.

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Role of quorum sensing in UVA-induced biofilm formation in Pseudomonas aeruginosa

Microbiology ◽

10.1099/mic.0.000932 ◽

2020 ◽

Vol 166 (8) ◽

pp. 735-750 ◽

Cited By ~ 1

Author(s):

Magdalena Pezzoni ◽

Ramón A. Pizarro ◽

Cristina S. Costa

Keyword(s):

Pseudomonas Aeruginosa ◽

Quorum Sensing ◽

Biofilm Formation ◽

Type Species ◽

Transcriptional Level ◽

Content Type ◽

Link Type ◽

Opportunistic Human Pathogen ◽

Biofilm Development

Pseudomonas aeruginosa , a versatile bacterium present in terrestrial and aquatic environments and a relevant opportunistic human pathogen, is largely known for the production of robust biofilms. The unique properties of these structures complicate biofilm eradication, because they make the biofilms very resistant to diverse antibacterial agents. Biofilm development and establishment is a complex process regulated by multiple regulatory genetic systems, among them is quorum sensing (QS), a mechanism employed by bacteria to regulate gene transcription in response to population density. In addition, environmental factors such as UVA radiation (400–315 nm) have been linked to biofilm formation. In this work, we further investigate the mechanism underlying the induction of biofilm formation by UVA, analysing the role of QS in this phenomenon. We demonstrate that UVA induces key genes of the Las and Rhl QS systems at the transcriptional level. We also report that pelA and pslA genes, which are essential for biofilm formation and whose transcription depends in part on QS, are significantly induced under UVA exposure. Finally, the results demonstrate that in a relA strain (impaired for ppGpp production), the UVA treatment does not induce biofilm formation or QS genes, suggesting that the increase of biofilm formation due to exposure to UVA in P. aeruginosa could rely on a ppGpp-dependent QS induction.

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The methylation-independent mismatch repair machinery in Pseudomonas aeruginosa

Microbiology ◽

10.1099/mic.0.001120 ◽

2021 ◽

Vol 167 (12) ◽

Author(s):

Yue Yuan On ◽

Martin Welch

Keyword(s):

Pseudomonas Aeruginosa ◽

Mismatch Repair ◽

Type Species ◽

Genetic Manipulation ◽

Microbial World ◽

Content Type ◽

E Coli ◽

Dna Mismatch ◽

Link Type ◽

Opportunistic Human Pathogen

Over the last 70 years, we’ve all gotten used to an Escherichia coli -centric view of the microbial world. However, genomics, as well as the development of improved tools for genetic manipulation in other species, is showing us that other bugs do things differently, and that we cannot simply extrapolate from E. coli to everything else. A particularly good example of this is encountered when considering the mechanism(s) involved in DNA mismatch repair by the opportunistic human pathogen, Pseudomonas aeruginosa (PA). This is a particularly relevant phenotype to examine in PA, since defects in the mismatch repair (MMR) machinery often give rise to the property of hypermutability. This, in turn, is linked with the vertical acquisition of important pathoadaptive traits in the organism, such as antimicrobial resistance. But it turns out that PA lacks some key genes associated with MMR in E. coli , and a closer inspection of what is known (or can be inferred) about the MMR enzymology reveals profound differences compared with other, well-characterized organisms. Here, we review these differences and comment on their biological implications.

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Antimicrobial resistance and multilocus sequence types of Stenotrophomonas maltophilia isolated from dogs and cats in Japan

Journal of Medical Microbiology ◽

10.1099/jmm.0.001344 ◽

2021 ◽

Vol 70 (4) ◽

Author(s):

Takae Shimizu ◽

Yuzo Tsuyuki ◽

Kenta Shimoike ◽

Keita Iyori ◽

Tadashi Miyamoto ◽

...

Keyword(s):

Stenotrophomonas Maltophilia ◽

Type Species ◽

Companion Animals ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Isolation Rate ◽

Content Type ◽

Mlst Analysis ◽

Link Type ◽

Sequence Types

As the representative multidrug-resistant pathogen, Stenotrophomonas maltophilia has multiple intrinsic and acquired resistances, including carbapenem resistance. In companion animals, the antimicrobial susceptibility and sequence types (STs) of S. maltophilia are not well understood due to its limited isolation rate. We investigated the antimicrobial susceptibilities and multilocus sequence types (MLSTs) of 38 S . maltophilia strains isolated from dogs and cats in Japan. Prevalence of resistance was detected for imipenem (100 %), aztreonam (94.7 %), piperacillin (65.8 %), trimethoprim–sulfamethoxazole (65.8 %), and ceftazidime (60.5 %). Rates of resistances to chloramphenicol, minocycline, and levofloxacin were low (2.6–5.3 %). MLST analysis revealed that all 38 strains were assigned to 34 STs, including 11 previously reported STs and 23 newly identified STs. Phylogenetic analysis of MLSTs enabled categorization of 13 isolates (34.2 %) into genogroup 6, which is a major genogroup of human isolates. Multinational surveillance would be needed to clarify the significance of antimicrobial-resistant S. maltophilia isolates from companion animals.

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Conservation of Rhodococcus equi (Magnusson 1923) Goodfellow and Alderson 1977 and rejection of Rhodococcus hoagii (Morse 1912) Kämpfer et al. 2014

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijsem.0.004090 ◽

2020 ◽

Vol 70 (5) ◽

pp. 3572-3576 ◽

Cited By ~ 2

Author(s):

José A. Vázquez-Boland ◽

Mariela Scortti ◽

Wim G. Meijer

Keyword(s):

Type Species ◽

Medical Literature ◽

Original Description ◽

Rhodococcus Equi ◽

Reasonable Assumption ◽

Taxonomic Study ◽

Human Pathogen ◽

Content Type ◽

Link Type ◽

Nomenclatural Change

A recent taxonomic study confirmed the synonymy of Rhodococcus equi (Magnusson 1923) Goodfellow and Alderson 1977 and Corynebacterium hoagii (Morse 1912) Eberson 1918. As a result, both R. equi and C. hoagii were reclassified as Rhodococcus hoagii comb. nov. in application of the principle of priority of the Prokaryotic Code. Because R. equi is a well-known animal and zoonotic human pathogen, and a bacterial name solidly established in the veterinary and medical literature, we and others argued that the nomenclatural change may cause error and confusion and be potentially perilous. We have now additionally found that the nomenclatural type of the basonym C. hoagii , ATCC 7005T, does not correspond with the original description of the species C. hoagii in the early literature. Its inclusion as the C. hoagii type on the Approved Lists 1980 results in a change in the characters of the taxon and in C. hoagii designating two different bacteria. Moreover, ATCC 7005, the only strain in circulation under the name C. hoagii , does not have a well documented history; it is unclear why it was deposited as C. hoagii and a possible mix-up with a Corynebacterium ( Rhodococcus ) equi isolate is a reasonable assumption. We therefore request the rejection of Rhodococcus hoagii as a nomen ambiguum, nomen dubium and nomen perplexum in addition to nomen periculosum, and conservation of the name Rhodococcus equi , according to Rules 56ab of the Code.

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