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Research in Microbiology 2022Maltocin P28, produced by Stenotrophomonas maltophilia P28, is an R-type phage tail-like bacteriocin (PTLB). Its gene cluster consists of 23 putative genes, including...
Maltocin P28, produced by Stenotrophomonas maltophilia P28, is an R-type phage tail-like bacteriocin (PTLB). Its gene cluster consists of 23 putative genes, including nine nonstructural genes and fourteen structural genes. In this work, three nonstructural genes, mpsA, mpsH and mpsR, were found to encode transcriptional regulators to control maltocin P28 synthesis. MpsA activated the transcription of mpsH and lysis genes. MpsH activated the transcription of structural genes. Under normal growth conditions, MpsR repressed the transcription of mpsA and the structural genes, as well as its own. When S. maltophilia P28 was treated with mitomycin C, an immediate and significant decrease in the amount of MpsR was observed, followed by derepressed expression of mpsA, mpsR and structural genes, a marked rise in the expression of all regulatory and structural genes, and finally a clear increase in the maltocin P28 production. Neither the recA gene nor the lexA gene was found to be involved in the induced synthesis of maltocin P28. Our study indicated that a unique mechanism regulates the expression of maltocin genes in S. maltophilia, representing a novel strategy for balancing the expression of PTLB genes in bacteria.
Topics: Bacteriocins; Multigene Family; Stenotrophomonas maltophilia
PubMed: 35569725
DOI: 10.1016/j.resmic.2022.103956 -
Veterinary Research Communications Feb 2022Tick-borne viruses and bacteria that can cause diseases of animals and humans have high impact and are of concern as significant threats to human health worldwide. In...
Tick-borne viruses and bacteria that can cause diseases of animals and humans have high impact and are of concern as significant threats to human health worldwide. In this research, we screened microorganisms related to those pathogens in ticks from dogs, a cat, and a cow. The techniques used were PCR, DNA sequencing and phylogenetic analysis to detect and classify the microorganisms [Flavivirus, severe fever with thrombocytopenia syndrome virus (SFTSV), Phlebovirus, Coronavirus, Canine Parvovirus, eubacteria, Coxiella and Rickettsia]. A novel virus named Phlebovirus-like-AYUT and Stenotrophomonas maltophilia bacteria were found in one individual tick (Rhipicephalus sanguineus s.l.) from a dog. All tick samples were negative for Rickettsia, while 9/21 (42.9 %) were positive for Coxiella bacteria. The novel virus "Phlebovirus-like-AYUT" (the name derives from Phra Nakhon Si Ayutthaya Province in Thailand) was resolved by phylogenetic analysis of the partial L segment by maximum likelihood (ML) method using MEGA X. The phylogenetic tree also indicated that the virus was related to Phlebovirus in brown dog ticks reported in Trinidad and Tobago. In contrast, Phlebovirus-like-AYUT was in a distinct clade from Lihan tick Phlebovirus-Thailand (LTPV), which was previously found in cow ticks, Rhipicephalus microplus, in Nan Province, Thailand. This study reports the Stenotrophomonas maltophilia bacterium with a novel Phlebovirus-like-AYUT in a brown dog tick. The roles of this bacterium in a virus-positive tick or in viral transmission from animal host requires further investigation.
Topics: Animals; Cattle; Cattle Diseases; Coinfection; Dog Diseases; Dogs; Female; Phlebovirus; Phylogeny; Rhipicephalus sanguineus; Stenotrophomonas maltophilia; Thailand
PubMed: 34725749
DOI: 10.1007/s11259-021-09855-7 -
Scientific Reports Dec 2023Prophages, which enables bacterial hosts to acquire novel traits, and increase genetic variation and evolutionary innovation, are considered to be one of the greatest...
Prophages, which enables bacterial hosts to acquire novel traits, and increase genetic variation and evolutionary innovation, are considered to be one of the greatest drivers of bacterial diversity and evolution. Stenotrophomonas maltophilia is widely distributed and one of the most important multidrug resistant bacteria in hospitals. However, the distribution and genetic diversity of S. maltophilia prophages have not been elucidated. In this study, putative prophages were predicted in S. maltophilia genomes by using virus prediction tools, and the genetic diversity and phylogeny of S. maltophilia and the prophages they harbor were further analyzed. A total of 356 prophage regions were predicted from 88 S. maltophilia genomes. Among them, 144 were intact prophages, but 77.09% of the intact prophages did not match any known phage sequences in the public database. The number of prophage carried by S. maltophilia is related to its host habitat and is an important factor affecting the size of the host genome, but it is not related to the genetic diversity of the prophage. The prediction of auxiliary genes encoded by prophage showed that antibiotic resistance genes was not predicted for any of the prophages except for one questionable prophage, while 53 virulence genes and 169 carbohydrate active enzymes were predicted from 11.24 and 44.1% prophages, respectively. Most of the prophages (72.29%) mediated horizontal gene transfer of S. maltophilia genome, but only involved in 6.25% of the horizontal gene transfer events. In addition, CRISPR prediction indicated 97.75% S. maltophilia strains contained the CRISPR-Cas system containing 818 spacer sequences. However, these spacer sequences did not match any known S. maltophilia phages, and only a few S. maltophilia prophages. Comparative genomic analysis revealed a highly conserved and syntenic organization with genomic rearrangement between the prophages and the known related S. maltophilia phages. Our results indicate a high prevalence and genetic diversity of prophages in the genome of S. maltophilia, as well as the presence of a large number of uncharacterized phages. It provides an important complement to understanding the diversity and biological characteristics of phages, as well as the interactions and evolution between bacteria and phages.
Topics: Prophages; Phylogeny; Stenotrophomonas maltophilia; Genomics; Gene Transfer, Horizontal
PubMed: 38135742
DOI: 10.1038/s41598-023-50449-x -
Respiratory Medicine Mar 2022Little information is available about Stenotrophomonas maltophilia in patients with bronchiectasis. We analyzed data from the US Bronchiectasis and NTM Research Registry...
INTRODUCTION
Little information is available about Stenotrophomonas maltophilia in patients with bronchiectasis. We analyzed data from the US Bronchiectasis and NTM Research Registry to determine its prevalence and association with patient characteristics and severity of disease.
METHODS
Baseline and follow-up data were entered into a central web-based database. Patients were grouped into four cohorts based on their baseline cultures: 1) S. maltophilia, no Pseudomonas aeruginsosa, 2) P. aeruginosa, no S. maltophilia, 3) No pathogens, 4) Pathogens other than P. aeruginosa and S. maltophilia. The association between S. maltophilia, demographic characteristics, pulmonary function, exacerbations and hospitalizations was assessed at baseline and one year follow-up.
RESULTS
Among 2659 patients, 134 (5.0%) had grown S. maltophilia at baseline. The prior exacerbation rate at baseline was similar in patients with S. maltophilia and P. aeruginosa, but significantly higher than the other two groups. Hospitalizations were more frequent in patients with S. maltophilia or P. aeruginosa. Pre-bronchodilator FEV1 among S. maltophilia patients was between that of Pseudomonas patients and patients without either organism, but was not significantly different from any of the other groups. For all risk-adjusted one-year outcomes, patients with S. maltophilia had a non-significant trend towards worse outcomes compared to patients without P. aeruginosa, but were more similar to patients with P aeruginosa.
DISCUSSION
Bronchiectasis patients with S. maltophilia may have worse outcomes than patients without this organism or without P. aeruginosa; further study is needed to determine if the non-significant trends we note are clinically significant.
Topics: Bronchiectasis; Humans; Lung; Pseudomonas aeruginosa; Registries; Stenotrophomonas maltophilia
PubMed: 35124355
DOI: 10.1016/j.rmed.2022.106746 -
Frontiers in Cellular and Infection... 2018is an opportunistic Gram-negative pathogen with increasing incidence in clinical settings. The most critical aspect of is its frequent resistance to a majority of the... (Review)
Review
is an opportunistic Gram-negative pathogen with increasing incidence in clinical settings. The most critical aspect of is its frequent resistance to a majority of the antibiotics of clinical use. Quorum Sensing (QS) systems coordinate bacterial populations and act as major regulatory mechanisms of pathogenesis in both pure cultures and poly-microbial communities. Disruption of QS systems, a phenomenon known as Quorum Quenching (QQ), represents a new promising paradigm for the design of novel antimicrobial strategies. In this context, we review the main advances in the field of QS in by paying special attention to Diffusible Signal Factor (DSF) signaling, Acyl Homoserine Lactone (AHL) responses and the controversial Ax21 system. Advances in the DSF system include regulatory aspects of DSF synthesis and perception by both -1 and -2 variant systems, as well as their reciprocal communication. Interaction via DSF of with unrelated organisms including bacteria, yeast and plants is also considered. Finally, an overview of the different QQ mechanisms involving as quencher and as object of quenching is presented, revealing the potential of this species for use in QQ applications. This review provides a comprehensive snapshot of the interconnected QS network that uses to sense and respond to its surrounding biotic or abiotic environment. Understanding such cooperative and competitive communication mechanisms is essential for the design of effective anti QS strategies.
Topics: Acyl-Butyrolactones; Anti-Infective Agents; Bacterial Proteins; Cross Infection; Cytokines; Drug Resistance, Multiple, Bacterial; Quorum Sensing; Signal Transduction; Stenotrophomonas maltophilia
PubMed: 29740543
DOI: 10.3389/fcimb.2018.00122 -
Microbiology Spectrum Aug 2022Fluoroquinolones have become a popular treatment option for Stenotrophomonas maltophilia infections. Although levofloxacin is most commonly used, delafloxacin...
Fluoroquinolones have become a popular treatment option for Stenotrophomonas maltophilia infections. Although levofloxacin is most commonly used, delafloxacin demonstrates comparable activity when evaluated under standard susceptibility testing conditions at neutral pH. At acidic pH, the activity of the anionic delafloxacin is improved, while the activity of the zwitterionic levofloxacin is reduced. Because the human respiratory tract has a pH of ~6.6 and is the most common site of S. maltophilia infection, it is vital to understand the activity of these agents in this environment. Therefore, levofloxacin and delafloxacin were tested against clinical S. maltophilia isolates via broth microdilution testing ( = 37) and time-kill analysis ( = 5) in neutral cation-adjusted Mueller-Hinton broth (CAMHB) (pH 7.3) and acidic CAMHB (aCAMHB) (pH 6.5). In CAMHB, MIC values were similar between levofloxacin and delafloxacin (8 mg/L versus 8 mg/L). In aCAMHB, levofloxacin MICs did not change, while delafloxacin MICs decreased by a median of 4 log dilutions (MIC values of 8 mg/L versus 0.25 mg/L). In time-kill analyses, levofloxacin and delafloxacin at the maximum drug concentration for the free drug () were bactericidal against 3 and 2 isolates in CAMHB, respectively. In aCAMHB, levofloxacin was not bactericidal against any isolate, while delafloxacin was bactericidal against the same 2 isolates. Relative to CAMHB, levofloxacin activity was reduced by 2.5 log CFU/mL in aCAMHB, whereas delafloxacin activity was increased 2.7 log CFU/mL. Although the bactericidal activity of levofloxacin against S. maltophilia was attenuated in an acidic environment in this study, the increased potency of delafloxacin at pH 6.5 did not translate into improved bactericidal activity in time-kill analyses, compared to pH 7.3. Stenotrophomonas maltophilia most often infects the lungs, where the physiologic environment is naturally slightly acidic (pH ~6.6), compared to most parts of the body (such as the bloodstream), which have neutral pH values (~7.4). Pneumonia due to S. maltophilia is often treated with the antibiotic levofloxacin, despite the activity of levofloxacin being known to be impaired at acidic pH. Unfortunately, currently available methods for susceptibility testing of levofloxacin against S. maltophilia are performed at a neutral pH and therefore may not accurately represent the activity of levofloxacin at the site of infection in the lungs. A similar but newer antibiotic in the same class as levofloxacin, namely, delafloxacin, is not affected by being in an acidic environment and may actually work better at lower pH values. Therefore, the purpose of this study was to investigate whether one drug might be better than the other in this setting by testing each agent's ability to kill S. maltophilia at pH 7.3 and pH 6.5. These findings could then be used to design confirmatory studies that may ultimately impact which drug is given to patients with lung infections due to S. maltophilia.
Topics: Anti-Bacterial Agents; Fluoroquinolones; Gram-Negative Bacterial Infections; Humans; Hydrogen-Ion Concentration; Levofloxacin; Microbial Sensitivity Tests; Stenotrophomonas maltophilia
PubMed: 35862943
DOI: 10.1128/spectrum.02705-21 -
Microbiology Spectrum Aug 2023Stenotrophomonas maltophilia is increasingly recognized as an important nosocomial pathogen among the Gram-negative bacteria. Intrinsic resistance to different classes...
Stenotrophomonas maltophilia is increasingly recognized as an important nosocomial pathogen among the Gram-negative bacteria. Intrinsic resistance to different classes of antibiotics makes treatment of infections challenging. A deeper understanding of S. maltophilia physiology and virulence requires molecular genetic tools. Here, we describe the implementation of tetracycline-dependent gene regulation ( regulation) in this bacterium. The exploited regulatory sequence of transposon Tn contained the gene and three intertwined promoters, one of which was required for regulated expression of a target gene or operon. The episomal architecture was tested with a variant as a quantifiable reporter. Fluorescence intensity was directly correlated with the concentration of the inducer anhydrotetracycline (ATc) applied and the duration of induction. Also, the expression of the operon of S. maltophilia K279a was subjected to control. These genes code for the synthesis of dTDP-l-rhamnose, an activated nucleotide sugar precursor of lipopolysaccharide (LPS) formation. A Δ mutant was complemented with a plasmid carrying this operon downstream of the sequence. In the presence of ATc, the LPS pattern was similar to that of wild-type S. maltophilia, whereas without the inducer, fewer and apparently shorter O-antigen chains were detected. This underscores the functionality and usefulness of the system for gene regulation and, prospectively, the validation of targets for new anti-S. maltophilia drugs. Stenotrophomonas maltophilia is an emerging pathogen in hospital settings and poses a threat to immunocompromised patients. Due to a high level of resistance to different types of antibiotics, treatment options are limited. We here adapted a tool for inducible expression of genes of interest, known as the system, to S. maltophilia. Genes relevant to producing surface carbohydrate structures (lipopolysaccharide [LPS]) were placed under the control of the system. In the presence of an inducer, the LPS pattern was similar to that of wild-type S. maltophilia, whereas in the "off" state of the system (without inducer), fewer and apparently shorter versions of LPS were detected. The system is functional in S. maltophilia and may be helpful to reveal gene-function relationships to gain a deeper understanding of the bacterium's physiology and virulence.
Topics: Humans; Stenotrophomonas maltophilia; Lipopolysaccharides; Anti-Bacterial Agents; Gene Expression
PubMed: 37378537
DOI: 10.1128/spectrum.01576-23 -
Anatolian Journal of Cardiology Dec 2017
Topics: Aged; Diagnosis, Differential; Echocardiography; Gram-Negative Bacterial Infections; Humans; Lung Neoplasms; Male; Pericarditis; Stenotrophomonas maltophilia
PubMed: 29256885
DOI: 10.14744/AnatolJCardiol.2017.8024 -
International Journal of Molecular... Jul 2020Although strains are efficient biocontrol agents, their field applications have raised concerns due to their possible threat to human health. The non-pathogenic... (Comparative Study)
Comparative Study
Although strains are efficient biocontrol agents, their field applications have raised concerns due to their possible threat to human health. The non-pathogenic species, which is closely related to has been proposed as an alternative. However, knowledge regarding the genetics of is limited. Thus, the aim of the study was to define any genetic differences between the species and to characterise their ability to promote the growth of plant hosts as well as to enhance phytoremediation efficiency. We compared 37 strains that belong to both species using the tools of comparative genomics and identified 96 genetic features that are unique to (e.g., chitin-binding protein, mechanosensitive channels of small conductance and KGG repeat-containing stress-induced protein) and 59 that are unique to (e.g., glucosylglycerol-phosphate synthase, cold shock protein with the DUF1294 domain, and pteridine-dependent dioxygenase-like protein). The strains from both species have a high potential for biocontrol, which is mainly related to the production of keratinases (KerSMD and KerSMF), proteinases and chitinases. Plant growth promotion traits are attributed to the biosynthesis of siderophores, spermidine, osmoprotectants such as trehalose and glucosylglycerol, which is unique to . In eight out of 37 analysed strains, the genes that are required to degrade protocatechuate were present. While our results show genetic differences between the two species, they had a similar growth promotion potential. Considering the information above, constitutes a promising alternative for for use in agricultural biotechnology.
Topics: Biodegradation, Environmental; Biological Control Agents; DNA, Bacterial; Enzymes; Gene Ontology; Genes, Bacterial; Genome, Bacterial; Genomics; Host-Pathogen Interactions; Mechanotransduction, Cellular; Phylogeny; Plant Proteins; Quorum Sensing; Species Specificity; Stenotrophomonas; Stenotrophomonas maltophilia; Virulence; Xenobiotics
PubMed: 32664682
DOI: 10.3390/ijms21144922 -
Polish Journal of Microbiology Sep 2023This work investigated the genetic relationship among strains in fecal samples from dairy cows in northeast China and identified the dominant β-lactamase genotype. One...
This work investigated the genetic relationship among strains in fecal samples from dairy cows in northeast China and identified the dominant β-lactamase genotype. One hundred and six samples were collected from two randomly selected cow farms in northeast China, and the isolates were identified with MALDI-TOF/MS. Whole-genome sequencing was conducted using Illumina HiSeq 4000-PE150 platform (Illumina, Inc., USA). The antimicrobial resistance genes were detected using CGE services. The phylogenetic analysis of strains was performed by Roary and MEGA X. In total, 24 isolates were isolated. The results of resistome analysis showed all strains carrying gene, which was the only β-lactamase genotype. In addition, the aminoglycoside resistance genes and were found. The phylogenetic tree indicated the clonal diversity of in these two regions and the clonal relatedness of the strains from these regions. This study first investigated the dissemination and characterization of isolates from dairy cows in northeast China and provided evidence of the potential transmission between two provinces. Furthermore, it indicated was the most prevalent genotype of β-lactamase in these regions.
Topics: Animals; Female; Cattle; Stenotrophomonas maltophilia; Phylogeny; China; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; beta-Lactamases
PubMed: 37725894
DOI: 10.33073/pjm-2023-032