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MBio Jan 2016Bacterial interspecies interactions play clinically important roles in shaping microbial community composition. We observed that Corynebacterium spp. are overrepresented...
UNLABELLED
Bacterial interspecies interactions play clinically important roles in shaping microbial community composition. We observed that Corynebacterium spp. are overrepresented in children free of Streptococcus pneumoniae (pneumococcus), a common pediatric nasal colonizer and an important infectious agent. Corynebacterium accolens, a benign lipid-requiring species, inhibits pneumococcal growth during in vitro cocultivation on medium supplemented with human skin surface triacylglycerols (TAGs) that are likely present in the nostrils. This inhibition depends on LipS1, a TAG lipase necessary for C. accolens growth on TAGs such as triolein. We determined that C. accolens hydrolysis of triolein releases oleic acid, which inhibits pneumococcus, as do other free fatty acids (FFAs) that might be released by LipS1 from human skin surface TAGs. Our results support a model in which C. accolens hydrolyzes skin surface TAGS in vivo releasing antipneumococcal FFAs. These data indicate that C. accolens may play a beneficial role in sculpting the human microbiome.
IMPORTANCE
Little is known about how harmless Corynebacterium species that colonize the human nose and skin might impact pathogen colonization and proliferation at these sites. We show that Corynebacterium accolens, a common benign nasal bacterium, modifies its local habitat in vitro as it inhibits growth of Streptococcus pneumoniae by releasing antibacterial free fatty acids from host skin surface triacylglycerols. We further identify the primary C. accolens lipase required for this activity. We postulate a model in which higher numbers of C. accolens cells deter/limit S. pneumoniae nostril colonization, which might partly explain why children without S. pneumoniae colonization have higher levels of nasal Corynebacterium. This work narrows the gap between descriptive studies and the needed in-depth understanding of the molecular mechanisms of microbe-microbe interactions that help shape the human microbiome. It also lays the foundation for future in vivo studies to determine whether habitat modification by C. accolens could be promoted to control pathogen colonization.
Topics: Anti-Bacterial Agents; Antibiosis; Carrier State; Child; Child, Preschool; Corynebacterium; Fatty Acids, Nonesterified; Humans; Hydrolysis; Infant; Microbiota; Nasal Cavity; Pneumococcal Infections; Skin; Streptococcus pneumoniae; Triglycerides; Triolein
PubMed: 26733066
DOI: 10.1128/mBio.01725-15 -
Pathogens (Basel, Switzerland) Feb 2021is the predominant species of the healthy human nasal microbiota, and its relative abundance is decreased in the context of chronic rhinosinusitis (CRS). This study...
is the predominant species of the healthy human nasal microbiota, and its relative abundance is decreased in the context of chronic rhinosinusitis (CRS). This study aimed to evaluate the antimicrobial potential of isolated from a healthy human nasal cavity against planktonic and biofilm growth of () and methicillin-resistant (MRSA) clinical isolates (CIs) from CRS patients. Nasal swabs from twenty non-CRS control subjects were screened for the presence of using microbiological and molecular techniques. CIs and their culture supernatants were tested for their antimicrobial activity against eight and eight MRSA 4CIs and ATCC25923. The anti-biofilm potential of cell-free culture supernatants (CFCSs) on biofilms was also assessed. Of the 20 nasal swabs, 10 CIs were identified and confirmed with gene sequencing. All isolates showed variable antimicrobial activity against eight out of 8 and seven out of eight MRSA CIs. Culture supernatants from all CIs exhibited a significant dose-dependent antibacterial activity ( < 0.05) against five out of five representative and MRSA CIs. This inhibition was abolished after proteinase K treatment. supernatants induced a significant reduction in metabolic activity and biofilm biomass of and MRSA CIs compared to untreated growth control ( < 0.05). exhibited antimicrobial activity against and MRSA CIs in both planktonic and biofilm forms and holds promise for the development of innovative probiotic therapies to promote sinus health.
PubMed: 33672855
DOI: 10.3390/pathogens10020207 -
Frontiers in Microbiology 2021The stability and composition of the airway microbiome is an important determinant of respiratory health. Some airway bacteria are considered to be beneficial due to...
The stability and composition of the airway microbiome is an important determinant of respiratory health. Some airway bacteria are considered to be beneficial due to their potential to impede the acquisition and persistence of opportunistic bacterial pathogens such as . Among such organisms, the presence of species correlates with reduced in both adults and children, in whom abundance is predictive of infection risk. Previously, was shown to express a lipase which cleaves host lipids, resulting in the production of fatty acids that inhibit growth of . However, it was unclear whether this mechanism contributes to - interactions . To address this question, we developed a mouse model for colonization in which colonization with either or another species, , significantly reduced acquisition in the upper airway and infection in the lung. Moreover, the lungs of co-infected mice had reduced pro-inflammatory cytokines and inflammatory myeloid cells, indicating resolution of infection-associated inflammation. The inhibitory effect of on was mediated by lipase-dependent and independent effects, indicating that both this and other bacterial factors contribute to -mediated protection in the airway. We also identified a previously uncharacterized bacterial lipase in that is required for inhibition of growth . Together, these findings demonstrate the protective potential of airway species and establish a new model for investigating the impact of commensal microbiota, such as , on maintaining respiratory health.
PubMed: 35082772
DOI: 10.3389/fmicb.2021.804935 -
Microbiological Research Nov 2021Corynebacterium accolens strains are increasingly recognized as beneficial bacteria that can confer a health benefit on the host. In the current study, the probiotic...
Corynebacterium accolens strains are increasingly recognized as beneficial bacteria that can confer a health benefit on the host. In the current study, the probiotic potential of three C. accolens strains, C779, C781 and C787 derived from a healthy human nasal cavity were investigated. These strains were examined for their adhesion to HNECs, competition with Staphylococcus aureus for adhesion, toxicity, induction of IL-6, antibiotic susceptibility and the presence of antibiotic resistance and virulence genes. Furthermore, the safety and efficacy of strains were evaluated in vivo using Caenorhabditis elegans. The adhesion capacity of C. accolens to HNECs was strain-dependent. Highest adhesion was observed for strain C781. None of the C. accolens strains tested caused cell lysis. All strains were able to outcompete S. aureus for cell adhesion and caused a significant decrease of IL-6 production by HNECs co-exposed to S. aureus when compared to the control groups. All strains were sensitive or showed intermediate sensitivity to 10 different antibiotics. Whole Genome Sequence analysis showed C. accolens C781 and C787 did not possess antibiotic resistance genes whereas strain C779 harboured 5 genes associated with resistance to Aminoglycoside, Chloramphenicol and Erythromycin. In addition, no virulence genes were detected in any of the 3 strains. Moreover, the tested strains had no detrimental effect on worm survival and induced protection from S. aureus-mediated infection. Taken all together, C. accolens strains, C781 and C787 displayed probiotic potential and hold promise for use in clinical applications for combating dysbiosis in chronic rhinosinusitis.
PubMed: 34875424
DOI: 10.1016/j.micres.2021.126927 -
Frontiers in Microbiology 2022() is a common nasal colonizer, whereas () is typically regarded a pathogenic organism in patients with chronic rhinosinusitis (CRS). This study aims to evaluate the...
BACKGROUND
() is a common nasal colonizer, whereas () is typically regarded a pathogenic organism in patients with chronic rhinosinusitis (CRS). This study aims to evaluate the interaction of the two bacteria .
METHODS
Clinical isolates of and from sinonasal swabs, as well as primary human nasal epithelial cells (HNECs) cultured from cellular brushings of both healthy and CRS patients were used for this study. The cell-free culture supernatants of all isolates grown alone and in co-cultures were tested for their effects on transepithelial electrical resistance (TER), FITC-Dextran permeability, lactate dehydrogenase (LDH), and IL-6 and IL-8 secretion of HNECs. Confocal scanning laser microscopy and immunofluorescence were also used to visualize the apical junctional complexes. cell-free culture supernatants were also tested for antimicrobial activity and growth on planktonic and biofilm growth.
RESULTS
The cell-free culture supernatants of 3\ strains (at 60% for reference strain and 30% concentration for clinical strains) inhibited the growth of both the planktonic reference and clinical strains significantly. The cell-free culture supernatants caused no change in the TER or FITC-Dextran permeability of the HNEC-ALI cultures, while the cell-free culture supernatants of strains had a detrimental effect. Cell-free culture supernatants of co-cultured with both the clinical and reference strains of delayed the -dependent mucosal barrier damage in a dose-dependent manner.
CONCLUSION
cell-free culture supernatants appear to inhibit the growth of the planktonic bacteria, and may reduce the mucosal barrier damage caused by .
PubMed: 36187946
DOI: 10.3389/fmicb.2022.984741 -
GeroScience Oct 2023The SARS-CoV-2 virus is still causing a worldwide problem. The virus settles primarily on the nasal mucosa, and the infection and its course depend on individual...
The SARS-CoV-2 virus is still causing a worldwide problem. The virus settles primarily on the nasal mucosa, and the infection and its course depend on individual susceptibility. Our aim was to investigate the nasopharynx composition's role in the individual susceptibility. During the first phase of SARS-CoV-2 pandemic, nasopharyngeal microbiome samples of close contact unvaccinated patients were investigated by 16S rRNA analysis and by culturing. The whole genome of cultured Corynebacteria was sequenced. The relative expression of ACE2, TMPRSS2, and cathepsin L on Caco-2 cells and the strength of S1-ACE2 binding were determined in the presence of Corynebacteria. From 55 close contacts exposed to identical SARS-CoV-2 exposure, 26 patients became infected and 29 remained uninfected. The nasopharyngeal microbiome analysis showed significantly higher abundance of Corynebacteria in uninfected group. Corynebacterium accolens could be cultivated only from uninfected individuals and Corynebacterium propinquum from both infected and uninfected. Corynebacteria from uninfected patient significantly reduced the ACE2 and cathepsin L expression. C. accolens significantly reduced the TMPRSS2 expression compared to other Corynebacteria. Furthermore, Corynebacterium spp. weakened the binding of the S1-ACE2. Most C. accolens isolates harbored the TAG lipase LipS1 gene. Based on these results, the presence of Corynebacterium spp. in the nasopharyngeal microbiota, especially C. accolens strains, could reduce the individual susceptibility to SARS-CoV-2 infection by several mechanisms: by downregulation the ACE2, the TMPRSS2 receptors, and cathepsin L in the host; through the inhibition of S1-ACE2 binding; and lipase production. These results suggest the use of C. accolens strains as probiotics in the nasopharynx in the future.
Topics: Humans; COVID-19; SARS-CoV-2; Cathepsin L; Angiotensin-Converting Enzyme 2; RNA, Ribosomal, 16S; Caco-2 Cells; Corynebacterium; Nasopharynx; Lipase
PubMed: 37338780
DOI: 10.1007/s11357-023-00850-1 -
Frontiers in Microbiology 2022While populations at risk for severe SARS-CoV-2 infections have been clearly identified, susceptibility to the infection and its clinical course remain unpredictable. As...
While populations at risk for severe SARS-CoV-2 infections have been clearly identified, susceptibility to the infection and its clinical course remain unpredictable. As the nasopharyngeal microbiota may promote the acquisition of several respiratory infections and have an impact on the evolution of their outcome, we studied the nasopharyngeal microbiota of COVID-19 patients in association with baseline disease-related clinical features compared to that of patients tested negative. We retrospectively analyzed 120 nasopharyngeal pseudonymized samples, obtained for diagnosis, divided into groups (infected patients with a favorable outcome, asymptomatic, and deceased patients) and patients tested negative for SARS-CoV-2, by using Illumina-16S ribosomal ribonucleic acid (rRNA) sequencing and specific polymerase chain reaction (PCR) targeting pathogens. We first found a depletion of anaerobes among COVID-19 patients, irrespective of the clinical presentation of the infection ( < 0.029). We detected 9 taxa discriminating patients tested positive for SARS-CoV-2 from those that were negative including ( ≤ 0.05), ( ≤ 0.05), ( ≤ 0.01), ( ≤ 0.05), subsp. ( ≤ 0.001), and ( ≤ 0.001) with 16S rRNA sequencing, and ( ≤ 0.01), ( ≤ 0.01), and ( ≤ 0.05) using real-time PCR. By designing a specific real-time PCR, we also demonstrated that is decreased in asymptomatic individuals compared to other SARS-CoV 2 positive patients. These findings indicate that the nasopharyngeal microbiota as in any respiratory infection plays a role in the clinical course of the disease. Further studies are needed to elucidate the potential role in the clinical course of the disease of , and more specifically in order to include them as predictors of the severity of COVID-19.
PubMed: 35655997
DOI: 10.3389/fmicb.2022.871627 -
BioMed Research International 2022Methicillin-resistant (MRSA) is one of the main bacterial pathogens causing chronic infections, mainly because of its capacity to produce biofilm. Biofilm production is... (Review)
Review
BACKGROUND
Methicillin-resistant (MRSA) is one of the main bacterial pathogens causing chronic infections, mainly because of its capacity to produce biofilm. Biofilm production is one of the underlying strategies for antibacterial drug resistance. Accordingly, preventing and attenuating biofilm production has become an emerging approach to controlling persistent infections. Therefore, this scoping review is aimed at surveying the published literature describing the usage of probiotics and their derivatives against biofilm-producing MRSA.
METHODS
Updated literature searches were conducted across seven electronic databases including Web of Science, PubMed, Scopus, Cochrane Library, ProQuest, Embase, and Google Scholar to identify all original published articles about probiotics against MRSA. In this regard, studies were summarized and analyzed in the present review.
RESULTS
In the reviewed studies, various microorganisms and compounds were used as probiotics as follows: species (8 studies), species (4 studies), species (2 studies), species (2 studies), (1 study), (1 study), and derived Nisin (3 studies). Based on our comprehensive search, 21 studies with eligibility criteria were included in the present review including 12 studies on clinical strains, 6 studies on ATCC, 2 studies simultaneously on clinical and standard strains, and finally 1 study on food sample.
CONCLUSIONS
Our study showed that there was an increasing trend in the number of publications reporting probiotics against biofilm-producing MRSA. The results of this scoping review could use to guide the undertaking of the subsequent systematic reviews. In summary, probiotics with antimicrobial and antibiofilm properties can use as an embedded agent in food products or as a biopharmaceutical in the prevention and treatment of MRSA infections.
Topics: Humans; Methicillin-Resistant Staphylococcus aureus; Anti-Bacterial Agents; Staphylococcal Infections; Probiotics; Biofilms; Microbial Sensitivity Tests
PubMed: 36605101
DOI: 10.1155/2022/4959487 -
The Journal of Experimental Medicine Mar 2018How defined microbes influence the skin immune system remains poorly understood. Here we demonstrate that , dominant members of the skin microbiota, promote a dramatic...
How defined microbes influence the skin immune system remains poorly understood. Here we demonstrate that , dominant members of the skin microbiota, promote a dramatic increase in the number and activation of a defined subset of γδ T cells. This effect is long-lasting, occurs independently of other microbes, and is, in part, mediated by interleukin (IL)-23. Under steady-state conditions, the impact of is discrete and noninflammatory. However, when applied to the skin of a host fed a high-fat diet, alone promotes inflammation in an IL-23-dependent manner. Such effect is highly conserved among species of and dependent on the expression of a dominant component of the cell envelope, mycolic acid. Our data uncover a mode of communication between the immune system and a dominant genus of the skin microbiota and reveal that the functional impact of canonical skin microbial determinants is contextually controlled by the inflammatory and metabolic state of the host.
Topics: Animals; Cell Membrane; Cell Proliferation; Corynebacterium; Humans; Immunity; Inflammation; Interleukin-17; Interleukin-23; Lymphocyte Activation; Mice, Inbred C57BL; Phylogeny; Receptors, Antigen, T-Cell, gamma-delta; Skin; T-Lymphocytes
PubMed: 29382696
DOI: 10.1084/jem.20171079 -
BMJ Case Reports Aug 2020A 79-year-old man with liver failure, hypertension and hyperlipidemia presented with a 1.5-month history of progressive nasal crusting and pain on the inside of the...
A 79-year-old man with liver failure, hypertension and hyperlipidemia presented with a 1.5-month history of progressive nasal crusting and pain on the inside of the nose, advancing into a necrotic columella and philtrum. On rigid endoscopy, debris extended to middle and inferior turbinate to midway posteriorly. Initial culture swabs and CT were negative. The patient underwent endoscopic biopsy of the lesion, with histopathological findings revealing abundant acute inflammation and minute fragments of atypical squamous epithelium, favouring reactive atypia. Non-invasive fungal hyphae were identified. Bacterial cultures revealed , , species and A current literature search failed to find other published cases of nasal infections. is generally difficult to isolate on swab culture as the surrounding tissue is necrosed; this case highlights the importance of reconsidering bacterial infection and obtaining a tissue biopsy in the case of non-healing necrotic-appearing tissue with negative culture swab and CT without evidence of mass.
Topics: Aged; Anti-Bacterial Agents; Diagnosis, Differential; Humans; Immunocompromised Host; Liver Failure, Acute; Male; Necrosis; Nose; Pseudomonas Infections; Pseudomonas putida
PubMed: 32816933
DOI: 10.1136/bcr-2020-235778