Abstract:
:Commensal bacteria in the human nasal cavity are known to suppress opportunistic pathogen colonization by competing for limited space and nutrients. It has become increasingly apparent that some commensal bacteria also produce toxic compounds that directly inhibit or kill incoming competitors. Numerous studies suggest that microbial species-specific interactions can affect human nasal colonization by the opportunistic pathogen Staphylococcus aureus However, the complex and dynamic molecular interactions that mediate these effects on S. aureus nasal colonization are often difficult to study and remain poorly understood. Here, we show that Corynebacterium pseudodiphtheriticum, a common member of the normal nasal microbiota, mediates contact-independent bactericidal activity against S. aureus, including methicillin-resistant S. aureus (MRSA). Bacterial interaction assays revealed that S. aureus isolates that were spontaneously resistant to C. pseudodiphtheriticum killing could be recovered at a low frequency. To better understand the pathways associated with killing and resistance, a S. aureus transposon mutant library was utilized to select for resistant mutant strains. We found that insertional inactivation of agrC, which codes for the sensor kinase of the Agr quorum sensing (Agr QS) system that regulates expression of many virulence factors in S. aureus, conferred resistance to killing. Analysis of the spontaneously resistant S. aureus isolates revealed that each showed decreased expression of the Agr QS components. Targeted analysis of pathways regulated by Agr QS revealed that loss of the phenol-soluble modulins (PSMs), which are effectors of Agr QS, also conferred resistance to bactericidal activity. Transmission electron microscopy analysis revealed that C. pseudodiphtheriticum induced dramatic changes to S. aureus cell surface morphology that likely resulted in cell lysis. Taken together, these data suggest that C. pseudodiphtheriticum-mediated killing of S. aureus requires S. aureus virulence components. While S. aureus can overcome targeted killing, this occurs at the cost of attenuated virulence; loss of Agr QS activity would phenotypically resemble a S. aureus commensal state that would be unlikely to be associated with disease. Commensal competition resulting in dampened virulence of the competitor may represent an exciting and unexplored possibility for development of novel antimicrobial compounds.IMPORTANCE While some individuals are nasally colonized with S. aureus, the underlying factors that determine colonization are not understood. There is increasing evidence that indicates that resident bacteria play a role; some commensal species can eradicate S. aureus from the nasal cavity. Among these, Corynebacterium pseudodiphtheriticum can eliminate S. aureus from the human nose. We sought to understand this phenomenon at a molecular level and found that C. pseudodiphtheriticum produces a factor(s) that specifically kills S. aureus While resistant S. aureus isolates were recovered at a low frequency, resistance came at the cost of attenuated virulence in these strains. Molecular dissection of the specific strategies used by C. pseudodiphtheriticum to kill S. aureus could lead to the development of novel treatments or therapies. Furthermore, commensal competition that requires virulence components of the competitor may represent an exciting and unexplored possibility for development of novel antimicrobial compounds.
journal_name
mBiojournal_title
mBioauthors
Hardy BL,Dickey SW,Plaut RD,Riggins DP,Stibitz S,Otto M,Merrell DSdoi
10.1128/mBio.02491-18subject
Has Abstractpub_date
2019-01-08 00:00:00issue
1issn
2150-7511pii
mBio.02491-18journal_volume
10pub_type
杂志文章相关文献
mBio文献大全abstract:UNLABELLED:As diet is considered the major regulator of the gut ecosystem, the overall objective of this work was to demonstrate that a detailed knowledge of the phytochemical composition of food could add to our understanding of observed changes in functionality and activity of the gut microbiota. We used metatranscri...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.01263-15
更新日期:2015-10-27 00:00:00
abstract::Nonlytic exocytosis is a process in which previously ingested microbes are expelled from host phagocytes with the concomitant survival of both cell types. This process has been observed in the interaction of Cryptococcus spp. and other fungal cells with phagocytes as distant as mammalian, bird, and fish macrophages an...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02085-20
更新日期:2020-09-08 00:00:00
abstract::In Escherichia coli, FtsEX coordinates peptidoglycan (PG) synthesis and hydrolysis at the septum. It acts on FtsA in the cytoplasm to promote recruitment of septal PG synthetases and recruits EnvC, an activator of septal PG hydrolases, in the periplasm. Following recruitment, ATP hydrolysis by FtsEX is thought to regu...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.01247-20
更新日期:2020-07-07 00:00:00
abstract:UNLABELLED:Human immunodeficiency virus type 1 (HIV-1) Nef enhances virus replication and contributes to immune evasion in vivo, but the underlying molecular mechanisms remain incompletely defined. Nef interferes with host cell actin dynamics to restrict T lymphocyte responses to chemokine stimulation and T cell recept...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.01309-15
更新日期:2015-09-08 00:00:00
abstract::Our knowledge of cell cycle regulatory mechanisms in apicomplexan parasites is very limited. In this study, we describe a novel Toxoplasma gondii factor that has a vital role in chromosome replication and the regulation of cytoplasmic and nuclear mitotic structures, and we named this factor ECR1 for essential for chro...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00579-17
更新日期:2017-08-22 00:00:00
abstract::Host-associated microbial communities are shaped by extrinsic and intrinsic factors to the holobiont organism. Environmental factors and microbe-microbe interactions act simultaneously on the microbial community structure, making the microbiome dynamics challenging to predict. The coral microbiome is essential to the ...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02691-19
更新日期:2020-03-03 00:00:00
abstract::Cell surface expression of sialic acid has been reported to decrease during immune cell activation, but the significance and regulation of this phenomenon are still being investigated. The major human bacterial pathogen Streptococcus pneumoniae causes pneumonia, sepsis and meningitis, often accompanied by strong infla...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00220-11
更新日期:2012-01-03 00:00:00
abstract::Bats are reservoirs for many RNA viruses that are highly pathogenic in humans yet relatively apathogenic in the natural host. It has been suggested that differences in innate immunity are responsible. The antiviral OAS-RNase L pathway is well characterized in humans, but there is little known about its activation and ...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02414-19
更新日期:2019-11-12 00:00:00
abstract:UNLABELLED:The bacterial flagellum is driven by a bidirectional rotary motor, which propels bacteria to swim through liquids or swarm over surfaces. While the functions of the major structural and regulatory components of the flagellum are known, the function of the well-conserved FliL protein is not. In Salmonella and...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02367-14
更新日期:2015-02-24 00:00:00
abstract::Hepatitis E virus (HEV), a single-strand positive-sense RNA virus, is an understudied but important human pathogen. The virus can establish infection at a number of host tissues, including the small intestine and liver, causing acute and chronic hepatitis E as well as certain neurological disorders. The retinoic acid-...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.03103-19
更新日期:2020-01-14 00:00:00
abstract:UNLABELLED:Investigation of the human microbiome has revealed diverse and complex microbial communities at distinct anatomic sites. The microbiome of the human sebaceous follicle provides a tractable model in which to study its dominant bacterial inhabitant, Propionibacterium acnes, which is thought to contribute to th...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00279-12
更新日期:2012-09-25 00:00:00
abstract::The four dengue virus serotypes (DENV1 to 4) cause dengue, a major public health problem worldwide. Individuals exposed to primary DENV infections develop serotype-specific neutralizing antibodies, including strongly neutralizing antibodies targeting quaternary epitopes. To date, no studies have measured the levels an...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.01205-17
更新日期:2017-09-19 00:00:00
abstract::The pathogenic species of Cryptococcus are a major cause of mortality owing to severe infections in immunocompromised as well as immunocompetent individuals. Although antifungal treatment is usually effective, many patients relapse after treatment, and in such cases, comparative analyses of the genomes of incident and...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00166-17
更新日期:2017-03-07 00:00:00
abstract::Many viruses produce protein-coding and noncoding subgenomic RNAs (sgRNAs) that are critical for infection. A recently discovered pathway for viral sgRNA production uses exoribonuclease-resistant RNAs (xrRNAs), discrete folded RNA elements that block the processive exoribonucleolytic degradation of RNA. xrRNAs are wid...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02461-18
更新日期:2018-12-18 00:00:00
abstract:UNLABELLED:Clathrin-mediated endocytosis (CME) is conserved among eukaryotes and has been extensively analyzed at a molecular level. Here, we present an analysis of CME in the human fungal pathogen Candida albicans that shows the same modular structure as those in other fungi and mammalian cells. Intriguingly, C. albic...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00476-13
更新日期:2013-08-27 00:00:00
abstract::Fungal cell wall mannans are complex carbohydrate polysaccharides with different structures in yeasts and molds. In contrast to yeasts, their biosynthetic pathway has been poorly investigated in filamentous fungi. In Aspergillus fumigatus, the major mannan structure is a galactomannan that is cross-linked to the β-1,3...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02647-18
更新日期:2019-02-12 00:00:00
abstract:UNLABELLED:In infection experiments with genetically distinct Mycobacterium tuberculosis complex (MTBC) strains, we identified clade-specific virulence patterns in human primary macrophages and in mice infected by the aerosol route, both reflecting relevant model systems. Exclusively human-adapted M. tuberculosis linea...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00250-13
更新日期:2013-07-30 00:00:00
abstract::Enterococci are ancient commensal bacteria that recently emerged as leading causes of antibiotic-resistant, hospital-acquired infection. Vancomycin-resistant enterococci (VRE) epitomize why drug-resistant enterococcal infections are a problem: VRE readily colonize the antibiotic-perturbed gastrointestinal (GI) tract w...
journal_title:mBio
pub_type: 评论,杂志文章
doi:10.1128/mBio.00066-17
更新日期:2017-02-21 00:00:00
abstract:UNLABELLED:The nucleus has emerged as a key target for nucleomodulins, a family of effectors produced by bacterial pathogens to control host transcription or other nuclear processes. The virulence factor LntA from Listeria monocytogenes stimulates interferon responses during infection by inhibiting BAHD1, a nuclear pro...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00775-13
更新日期:2014-01-21 00:00:00
abstract::The concept that anaerobic microorganisms can directly accept electrons from Fe(0) has been controversial because direct metal-microbe electron transfer has previously only been indirectly inferred. Fe(0) oxidation was studied with Geobacter sulfurreducens strain ACL, an autotrophic strain that was previously shown to...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00303-19
更新日期:2019-05-14 00:00:00
abstract::Nutritional immunity is an elegant host mechanism used to starve invading pathogens of necessary nutrient metals. Calprotectin, a metal-binding protein, is produced abundantly by neutrophils and is found in high concentrations within inflammatory sites during infection. Group B Streptococcus (GBS) colonizes the gastro...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02302-20
更新日期:2020-11-10 00:00:00
abstract:UNLABELLED:A rapid and global emergence of azole resistance has been observed in the pathogenic fungus Aspergillus fumigatus over the past decade. The dominant resistance mechanism appears to be of environmental origin and involves mutations in the cyp51A gene, which encodes a protein targeted by triazole antifungal dr...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00536-15
更新日期:2015-06-02 00:00:00
abstract:UNLABELLED:The acquisition, delivery, and incorporation of metals into their respective metalloproteins are important cellular processes. These processes are tightly controlled in order to prevent exposure of cells to free-metal concentrations that could yield oxidative damage. Copper (Cu) is one such metal that is req...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00293-11
更新日期:2012-01-31 00:00:00
abstract::The disabling disorder known as chronic fatigue syndrome or myalgic encephalomyelitis (CFS/ME) has been linked in two independent studies to infection with xenotropic murine leukemia virus-related virus (XMRV) and polytropic murine leukemia virus (pMLV). Although the associations were not confirmed in subsequent studi...
journal_title:mBio
pub_type: 杂志文章,多中心研究
doi:10.1128/mBio.00266-12
更新日期:2012-09-18 00:00:00
abstract::Microbial carbon degradation and methanogenesis in wetland soils generate a large proportion of atmospheric methane, a highly potent greenhouse gas. Despite their potential to mitigate greenhouse gas emissions, knowledge about methane-consuming methanotrophs is often limited to lower-resolution single-gene surveys tha...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00815-18
更新日期:2018-11-06 00:00:00
abstract::Cerebral malaria is a severe neurological complication associated with sequestration of Plasmodium falciparum-infected erythrocytes (IE) in the brain microvasculature, but the specific binding interactions remain under debate. Here, we have generated an engineered three-dimensional (3D) human brain endothelial microve...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00420-19
更新日期:2019-05-28 00:00:00
abstract::Tuberculosis (TB), caused by Mycobacterium tuberculosis infection, remains a major cause of mortality and morbidity worldwide. One-third of the world population is infected with M. tuberculosis, and about 15 million people with latent tuberculosis infection (LTBI) reside in the United States. An estimated 10% of indiv...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02771-18
更新日期:2019-04-16 00:00:00
abstract::New drugs are needed to control the current tuberculosis (TB) pandemic caused by infection with Mycobacterium tuberculosis We report here on our work with AX-35, an arylvinylpiperazine amide, and four related analogs, which are potent antitubercular agents in vitro All five compounds showed good activity against M. tu...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.01276-18
更新日期:2018-10-09 00:00:00
abstract::The apparent mislocalization or excretion of cytoplasmic proteins is a commonly observed phenomenon in both bacteria and eukaryotes. However, reports on the mechanistic basis and the cellular function of this so-called "nonclassical protein secretion" are limited. Here we report that protein overexpression in recombin...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.02118-17
更新日期:2018-01-30 00:00:00
abstract:UNLABELLED:Elongins B and C are members of complexes that increase the efficiency of transcriptional elongation by RNA polymerase II (RNAPII) and enhance the monoubiquitination of histone H2B, an epigenetic mark of actively transcribed genes. Here we show that, in addition to its role in facilitating transcription of t...
journal_title:mBio
pub_type: 杂志文章
doi:10.1128/mBio.00023-11
更新日期:2011-03-29 00:00:00