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Enfermedades Infecciosas Y... Apr 2023Streptococcus bovis/equinus complex (SBEC) is a major cause of infective endocarditis (IE), although its incidence varies greatly depending on the geographical area. The...
INTRODUCTION
Streptococcus bovis/equinus complex (SBEC) is a major cause of infective endocarditis (IE), although its incidence varies greatly depending on the geographical area. The characteristics of IE caused by Streptococcus gallolyticus susp. gallolyticus are well known; there are hardly any descriptions of IE caused by other species or biotypes.
METHODS
Retrospective cohort study, from 1990 to 2019, of all SBEC IE in adults in three Spanish hospitals, Lugo (LH), Barcelona (BH) and Ferrol (FH) where the population is mainly rural, urban and mixed, respectively. The incidence of IE was analyzed in 3 areas. Clinical characteristics of IE (277 cases, 258 biotyped) were compared according to SBEC species and biotypes.
RESULTS
There are significant differences between the incidence of SBEC IE in HL (27.9/10) vs. HF and HB (8.8 and 7,1, respectively, p<0.001). We found significant differences (SbI vs. SbII) in mean age (68.5 vs. 73 years; p<0.01), duration of symptoms before diagnosis (46.9±46.5 vs. 30.4±40.9 days; p<0.01), presence of comorbidities: 39.1% (78) vs. 54.2% (32; p<0.04), predisposing heart illness:62.3% (124) vs. 81.3% (48; p<0.006), particularly, prosthetic or intravascular devices IE: 24.6% (49) vs. 52.4% (31; p<0.001), bi-valve involvement:23.6% (47) vs. 11.8% (7; p<0.05) and heart failure: 24.6% (49) vs. 38.9% (23; p<0.03). There were no significant differences in embolic events, need for surgery or mortality. The association with CRC was high in both groups: 77.7% vs. 66.6%.
CONCLUSIONS
IE due to SBEC has geographical variations in incidence and different clinical characteristics among biotypes. The association with CRC was high.
Topics: Adult; Humans; Streptococcus bovis; Retrospective Studies; Streptococcal Infections; Endocarditis, Bacterial; Endocarditis
PubMed: 36610830
DOI: 10.1016/j.eimce.2021.08.017 -
Journal of Microbiology, Immunology,... Jun 2023Streptococcus gallolyticus subsp. pasteurianus (SGSP) is a commensal in the intestinal tract and a potential pathogen of neonatal sepsis. During an 11-month period, four...
BACKGROUND
Streptococcus gallolyticus subsp. pasteurianus (SGSP) is a commensal in the intestinal tract and a potential pathogen of neonatal sepsis. During an 11-month period, four consecutive cases of SGSP sepsis were identified in one postnatal care unit (unit A) without evidence of vertical transmission. Therefore, we initiated this study to investigate the reservoir and mode of transmission of SGSP.
METHOD
We performed cultures of stool samples from healthcare workers in unit A and unit B (another unit without SGSP sepsis). If SGSP was positive in feces, we performed isolate pulsotyping and genotyping by using pulsed-field gel electrophoresis (PFGE) and analyzing random amplified polymorphic DNA (RAPD) patterns, respectively.
RESULTS
Five staff members in unit A showed positivity for SGSP. All samples from unit B were negative. We identified two major pulsogroups (groups C and D) by PFGE. In group D, the strains isolated from 3 consecutive sepsis patients (P1, P2 and P3) were closely related and clustered together as those from 2 staff members (C1/C2, C6). One staff (staff 4) had a direct contact history with patient (P1) confirmed to have the same clone. The last isolate of the patient in our study (P4) belonged to a distinct clone.
CONCLUSION
We found prolonged gut colonization of SGSP in healthcare workers and its epidemiological relatedness to neonatal sepsis. Fecal-oral or contact transmission is a possible route of SGSP infection. Fecal shedding among staff may be associated with neonatal sepsis in healthcare facilities.
Topics: Infant, Newborn; Humans; Streptococcus gallolyticus; Neonatal Sepsis; Streptococcal Infections; Random Amplified Polymorphic DNA Technique; Sepsis
PubMed: 36870812
DOI: 10.1016/j.jmii.2023.02.004 -
MBio Jan 2021subsp. is an emerging opportunistic pathogen responsible for septicemia and endocarditis in the elderly. Invasive infections by subsp. are strongly linked to the...
subsp. is an emerging opportunistic pathogen responsible for septicemia and endocarditis in the elderly. Invasive infections by subsp. are strongly linked to the occurrence of colorectal cancer (CRC). It was previously shown that increased secondary bile salts under CRC conditions enhance the bactericidal activity of gallocin, a bacteriocin produced by subsp. , enabling it to colonize the mouse colon by outcompeting resident enterococci (L. Aymeric, F. Donnadieu, C. Mulet, L. du Merle, et al., Proc Natl Acad Sci U S A 115:E283-E291, 2018, https://doi.org/10.1073/pnas.1715112115). In a separate study, we showed that subsp. produces and secretes a 21-mer peptide that activates bacteriocin production (A. Proutière, L. du Merle, B. Périchon, H. Varet, et al., mBio 11:e03187-20, 2020, https://doi.org/10.1128/mBio.03187-20). This peptide was named CSP because of its sequence similarity with competence-stimulating peptides found in other streptococci. Here, we demonstrate that CSP is a bona fide quorum sensing peptide involved in activation of gallocin gene transcription. We therefore refer to CSP as GSP (gallocin-stimulating peptide). GSP displays some unique features, since its N-terminal amino acid lies three residues after the double glycine leader sequence. Here, we set out to investigate the processing and export pathway that leads to mature GSP. Heterologous expression in of the genes encoding GSP and the BlpAB transporter is sufficient to produce the 21-mer form of GSP in the supernatant, indicating that subsp. BlpAB displays an atypical cleavage site. We also conducted the first comprehensive structure-activity relationship (SAR) analysis of subsp. GSP to identify its key structural features and found that unlike many other similar streptococci signaling peptides (such as CSPs), nearly half of the mature GSP sequence can be removed (residues 1 to 9) without significantly impacting the peptide activity. subsp. is an opportunistic pathogen associated with colorectal cancer (CRC) and endocarditis. subsp. utilizes quorum sensing (QS) to regulate the production of a bacteriocin (gallocin) and gain a selective advantage in colonizing the colon. In this article, we report (i) the first structure-activity relationship study of the subsp. QS pheromone that regulates gallocin production, (ii) evidence that the active QS pheromone is processed to its mature form by a unique ABC transporter and not processed by an extracellular protease, and (iii) supporting evidence of interspecies interactions between streptococcal pheromones. Our results revealed the minimal pheromone scaffold needed for gallocin activation and uncovered unique interactions between two streptococcal QS signals that warrant further study.
Topics: ATP-Binding Cassette Transporters; Bacterial Proteins; Bacteriocins; Bodily Secretions; Gene Expression Regulation, Bacterial; Membrane Transport Proteins; Peptide Hydrolases; Peptides; Pheromones; Quorum Sensing; Signal Transduction; Streptococcus gallolyticus; Transcriptome
PubMed: 33402540
DOI: 10.1128/mBio.03189-20 -
Frontiers in Cellular and Infection... 2021The opportunistic pathogen is one of the few intestinal bacteria that has been consistently linked to colorectal cancer (CRC). This study aimed to identify novel...
OBJECTIVE
The opportunistic pathogen is one of the few intestinal bacteria that has been consistently linked to colorectal cancer (CRC). This study aimed to identify novel -induced pathways in colon epithelial cells that could further explain how contributes to CRC development.
DESIGN AND RESULTS
Transcription profiling of cultured CRC cells that were exposed to revealed the specific induction of oxidoreductase pathways. Most prominently, and genes that encode phase I biotransformation enzymes were responsible for the detoxification or bio-activation of toxic compounds. A common feature is that these enzymes are induced through the Aryl hydrocarbon receptor (AhR). Using the specific inhibitor CH223191, we showed that the induction of was dependent on the AhR both using multiple CRC cell lines as using wild-type C57bl6 mice colonized with . Furthermore, we showed that CYP1 could also be induced by other intestinal bacteria and that a yet unidentified diffusible factor from the secretome (SGS) induces CYP1A enzyme activity in an AhR-dependent manner. Importantly, priming CRC cells with SGS increased the DNA damaging effect of the polycyclic aromatic hydrocarbon 3-methylcholanthrene.
CONCLUSION
This study shows that gut bacteria have the potential to modulate the expression of biotransformation pathways in colonic epithelial cells in an AhR-dependent manner. This offers a novel theory on the contribution of intestinal bacteria to the etiology of CRC by modifying the capacity of intestinal epithelial or (pre-)cancerous cells to (de)toxify dietary components, which could alter intestinal susceptibility to DNA damaging events.
Topics: Animals; Biotransformation; Colorectal Neoplasms; Cytochrome P-450 CYP1A1; Epithelial Cells; Mice; Mice, Inbred C57BL; Receptors, Aryl Hydrocarbon; Streptococcus gallolyticus
PubMed: 34778104
DOI: 10.3389/fcimb.2021.740704 -
BMC Research Notes Oct 2022Clinical outcomes of infection by S. gallolyticus have not been investigated extensively. We aimed to determine the prevalence of S. gallolyticus in tumor specimens...
OBJECTIVE
Clinical outcomes of infection by S. gallolyticus have not been investigated extensively. We aimed to determine the prevalence of S. gallolyticus in tumor specimens obtained from Iranian patients diagnosed with colorectal cancer. Polymerase chain reaction was used to confirm the presence of S. gallolyticus in patients' tissue samples.
RESULTS
Of 176 patients, 65 were diagnosed with colorectal cancer whereas 111 did not have any colon disease. No correlation was found between age, colonization with S. gallolyticus, gender, or risk factors. Overall, 72 (40%) patients carried S. gallolyticus; only 29% of the patients without colorectal cancer were positive for S. gallolyticus. Diagnosis of colorectal cancer and presence of S. gallolyticus significantly correlated (P = 0.006; odds ratio = 1.46; 95% CI = 1.21-3.87). Among the patients with colorectal cancer, 39 (60%) were positive with S. gallolyticus (P = 0.006) whereas 33 of 111 (29.7%) control subjects were positive for S. gallolyticus (P > 0.05); thus, 70.3% of the control subjects were not infected with S. gallolyticus. We found a high prevalence of S. gallolyticus among an Iranian cohort of patients with colorectal cancer. Despite previous reports, we report a positive correlation between colorectal cancer and S. gallolyticus colonization.
Topics: Colorectal Neoplasms; Humans; Iran; Odds Ratio; Streptococcal Infections; Streptococcus gallolyticus
PubMed: 36199123
DOI: 10.1186/s13104-022-06207-9 -
Infection and Drug Resistance 2023subspecies , formerly classified as biotype II/2 until 2003, is a rare cause of infant meningitis. Over the past 2 decades, only a few individual case reports and...
subspecies , formerly classified as biotype II/2 until 2003, is a rare cause of infant meningitis. Over the past 2 decades, only a few individual case reports and limited case series exist in the English-language literature. Moreover, the pathogenesis of subsp. meningitis in infants is unclear. Here we report a case of meningitis in a 6-week-old infant with hypothyroidism and preceding diarrhea. In this case, was cultured from cerebrospinal fluid, and then subspecies was identified by metagenomic next-generation Sequencing. The infant recovered uneventfully after a 4-week antibiotic course with ceftriaxone and vancomycin. Then combined with the literature of subsp. meningitis in infants, we discuss the possible etiology.
PubMed: 37727275
DOI: 10.2147/IDR.S425637 -
Journal of Medical Case Reports Oct 2021Streptococcus gallolyticus subspecies gallolyticus is a known pathogen that causes infective endocarditis, and most cases involve the left heart valves. We present the... (Review)
Review
BACKGROUND
Streptococcus gallolyticus subspecies gallolyticus is a known pathogen that causes infective endocarditis, and most cases involve the left heart valves. We present the first reported case of prosthetic tricuspid valve endocarditis caused by this microorganism. Relevant literature is reviewed.
CASE PRESENTATION
A 67-year-old Jewish female with a history of a prosthetic tricuspid valve replacement was admitted to the emergency department because of nonspecific complaints including effort dyspnea, fatigue, and a single episode of transient visual loss and fever. No significant physical findings were observed. Laboratory examinations revealed microangiopathic hemolytic anemia and a few nonspecific abnormalities. Transesophageal echocardiogram demonstrated a vegetation attached to the prosthetic tricuspid valve. The involved tricuspid valve was replaced by a new tissue valve, and Streptococcus gallolyticus subspecies gallolyticus was grown from its culture. Prolonged antibiotic treatment was initiated.
CONCLUSIONS
Based on this report and the reviewed literature, Streptococcus gallolyticus should be considered as a rare but potential causative microorganism in prosthetic right-sided valves endocarditis. The patient's atypical presentation emphasizes the need for a high index of suspicion for the diagnosis of infective endocarditis.
Topics: Aged; Endocarditis; Endocarditis, Bacterial; Female; Humans; Streptococcal Infections; Streptococcus gallolyticus; Tricuspid Valve
PubMed: 34702343
DOI: 10.1186/s13256-021-03125-5 -
Streptococcus gallolyticus bacteraemia and colorectal neoplasia: an old association with a new name.The Medical Journal of Australia Apr 2022
Topics: Bacteremia; Colorectal Neoplasms; Humans; Streptococcal Infections; Streptococcus gallolyticus
PubMed: 35240719
DOI: 10.5694/mja2.51447 -
Molecular Biology Reports Nov 2020There are several pieces of evidence regarding the role of bacteria, such as Streptococcus bovis/gallolyticus in the etiology of gastrointestinal diseases such as... (Comparative Study)
Comparative Study
There are several pieces of evidence regarding the role of bacteria, such as Streptococcus bovis/gallolyticus in the etiology of gastrointestinal diseases such as colorectal cancer (CRC) and inflammatory bowel disease (IBD). Therefore, the aim of this study was to detect S. gallolyticus subsp. gallolyticus (Sgg) in fecal samples of CRC and IBD patients by culture and molecular methods, in Ahvaz, southwest of Iran. A total of 106 fecal samples were collected from 22 CRC patients, 44 IBD patients, and 40 healthy individuals. The prevalence of Sgg was investigated by culture and polymerase chain reaction (PCR) with specific primers for sodA gene. The results of the stool culture showed that the overall prevalence of Sgg was 9 (13.6%) out of 66 patients. Meanwhile, the number of Sgg isolated from IBD and CRC patients was 7 (15.9%) and 2 (9%), respectively. The bacteria were not isolated from any of the control groups. On the basis of PCR, S. gallolyticus was detected in 24 (36.4%) out of 66 patients. Meanwhile, the number of IBD patients with positive sodA gene was 15 (34.1%) out of 44 cases. In CRC patients, the sodA gene was detected in 9 (40.9%) of 22 cases. Two (5%) of the specimens in the control group had the sodA gene. According to our results, S. gallolyticus subsp. gallolyticus might be involved in CRC and IBD pathogenesis. More investigation with different samples in the various areas might be shaded light on these results.
Topics: Adolescent; Adult; Aged; Bacterial Proteins; Colorectal Neoplasms; Control Groups; Feces; Female; Humans; Inflammatory Bowel Diseases; Iran; Male; Middle Aged; Polymerase Chain Reaction; Streptococcal Infections; Streptococcus gallolyticus; Superoxide Dismutase; Young Adult
PubMed: 33128683
DOI: 10.1007/s11033-020-05807-7 -
Microbiology Spectrum Aug 2023Streptococcus gallolyticus subsp. () is an opportunistic bacterial pathogen strongly associated with colorectal cancer. Here, through comparative genomics analysis, we...
Streptococcus gallolyticus subsp. () is an opportunistic bacterial pathogen strongly associated with colorectal cancer. Here, through comparative genomics analysis, we demonstrated that the genetic locus encoding the type VIIb secretion system (T7SSb) machinery is uniquely present in in two different arrangements. UCN34 carrying the most prevalent T7SSb genetic arrangement was chosen as the reference strain. To identify the effectors secreted by this secretion system, we inactivated the gene encoding the motor of this machinery. A comparison of the proteins secreted by UCN34 wild type and its isogenic Δ mutant revealed six T7SSb effector proteins, including the expected WXG effector EsxA and three LXG-containing proteins. In this work, we characterized an LXG-family toxin named herein TelE promoting the loss of membrane integrity. Seven homologs of TelE harboring a conserved glycine zipper motif at the C terminus were identified in different isolates. Scanning mutagenesis of this motif showed that the glycine residue at position 470 was crucial for TelE membrane destabilization activity. TelE activity was antagonized by a small protein TipE belonging to the DUF5085 family. Overall, we report herein a unique T7SSb effector exhibiting a toxic activity against nonimmune bacteria. In this study, 38 clinical isolates of Streptococcus gallolyticus subsp. () were sequenced and a genetic locus encoding the type VIIb secretion system (T7SSb) was found conserved and absent from 16 genomes of the closely related S. gallolyticus subsp. (). The T7SSb is a bona fide pathogenicity island. Here, we report that the model organism strain UCN34 secretes six T7SSb effectors. One of the six effectors named TelE displayed a strong toxicity when overexpressed in Escherichia coli. Our results indicate that TelE is probably a pore-forming toxin whose activity can be antagonized by a specific immunity protein named TipE. Overall, we report a unique toxin-immunity protein pair and our data expand the range of effectors secreted through T7SSb.
Topics: Streptococcus gallolyticus subspecies gallolyticus; Amino Acid Motifs; Glycine; Type VII Secretion Systems
PubMed: 37432124
DOI: 10.1128/spectrum.01481-23