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BMC Infectious Diseases Sep 2019Infections by Streptococcus gallolyticus subsp. pasteurianus (SGSP) is often underestimated. Herein, the epidemiological features and resistant characteristics of SGSP...
BACKGROUND
Infections by Streptococcus gallolyticus subsp. pasteurianus (SGSP) is often underestimated. Herein, the epidemiological features and resistant characteristics of SGSP in mainland China are characterized to enable a better understanding of its role in clinical infections.
METHODS
In the present work, 45 SGSP isolates were collected from the samples of bloodstream, urine, aseptic body fluid, and fetal membrane/placenta from patients in 8 tertiary general hospitals of 6 cities/provinces in China from 2011 to 2017. The identification of all isolates was performed using traditional biochemical methods, 16S rRNA and gyrB sequencing, followed by the characterization of their antibiotic resistance profiling and involved genes.
RESULTS
Among 34 non-pregnancy-related patients, 4 (4/34,11.8%) patients had gastrointestinal cancer, 10 (10/34, 29.4%) patients had diabetes, and one patient had infective endocarditis. Moreover, 11 cases of pregnant women were associated with intrauterine infection (9/11, 81.2%) and urinary tract infection (1/11, 9.1%), respectively. Except one, all other SGSP isolates were correctly identified by the BD Phoenix automated system. We found that all SGSP isolates were phenotypically susceptible to penicillin, ampicillin, cefotaxime, meropenem, and vancomycin. Forty strains (40/45, 88.9%) were both erythromycin and clindamycin-resistant, belonging to the cMLS phenotype, and the majority of them carried erm(B) gene (39/40, 97.5%). Although the cMLS/erm(B) constituted the most frequently identified phenotype/genotype combination (25/40, 62.5%) among all erythromycin-resistant cMLS isolates, erm(B)/erm(A), erm(B)/mef(A/E), and erm(B)/erm(T) was detected in 7, 4, and 3 isolates, respectively. Furthermore, 43 strains (43/45, 95.6%) were tetracycline-resistant, and out of these, 39 strains (39/45, 86.7%) carried tet(L), 27(27/45, 60.0%) strains carried tet(O), and 7 (7/45, 15.6%) strains carried tet(M), alone or combined, respectively. All erythromycin-resistant isolates were also resistant to tetracycline.
CONCLUSIONS
It is important to study and draw attention on SGSP, an underreported opportunistic pathogen targeting immunodeficient populations, notably elderly subjects, pregnant women and neonates.
Topics: Adult; Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; China; Drug Resistance, Bacterial; Female; Humans; Infant, Newborn; Male; Microbial Sensitivity Tests; Middle Aged; Phenotype; Phylogeny; Pregnancy; RNA, Ribosomal, 16S; Streptococcal Infections; Streptococcus gallolyticus; Uterine Diseases; Young Adult
PubMed: 31500570
DOI: 10.1186/s12879-019-4413-5 -
PloS One 2016Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) were classically clustered into the Lancefield Group D streptococci and despite...
Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) were classically clustered into the Lancefield Group D streptococci and despite their taxonomic reclassification still share a similar genetic content and environment. Both species are considered as opportunistic pathogens. E. faecium is often associated with nosocomial bacteraemia, and S. gallolyticus is sporadically found in endocarditis of colorectal cancer patients. In both cases, the source of infection is commonly endogenous with a translocation process that launches through the intestinal barrier. To get new insights into the pathological processes preceding infection development of both organisms, we used an in vitro model with Caco-2 cells to study and compare the adhesion, invasion and translocation inherent abilities of 6 E. faecium and 4 S. gallolyticus well-characterized isolates. Additionally, biofilm formation on polystyrene, collagen I and IV was also explored. Overall results showed that E. faecium translocated more efficiently than S. gallolyticus, inducing a destabilization of the intestinal monolayer. Isolates Efm106, Efm121 and Efm113 (p < .001 compared to Ef222) exhibited the higher translocation ability and were able to adhere 2-3 times higher than S. gallolyticus isolates. Both species preferred the collagen IV coated surfaces to form biofilm but the S. gallolyticus structures were more compact (p = .01). These results may support a relationship between biofilm formation and vegetation establishment in S. gallolyticus endocarditis, whereas the high translocation ability of E. faecium high-risk clones might partially explain the increasing number of bacteraemia.
Topics: Biofilms; Caco-2 Cells; Enterococcus faecium; Host-Pathogen Interactions; Humans; Streptococcus gallolyticus
PubMed: 27463203
DOI: 10.1371/journal.pone.0159159 -
World Journal of Gastrointestinal... Feb 2022Various studies have shown the interplay between the intestinal microbiome, environmental factors, and genetic changes in colorectal cancer (CRC) development. In this... (Review)
Review
Various studies have shown the interplay between the intestinal microbiome, environmental factors, and genetic changes in colorectal cancer (CRC) development. In this review, we highlight the various gut and oral microbiota associated with CRC and colorectal adenomas, and their proposed molecular mechanisms in relation to the processes of "the hallmarks of cancer", and differences in microbial diversity and abundance between race/ethnicity. Patients with CRC showed increased levels of enterotoxigenic () and . Higher levels of have been found in African American (AA) compared to Caucasian American (CA) patients. Pro-inflammatory bacteria such as and species were significantly higher in AAs. Also, AA patients have been shown to have decreased microbial diversity compared to CA patients. Some studies have shown that using microbiome profiles in conjunction with certain risk factors such as age, race and body mass index may help predict healthy colon one with adenomas or carcinomas. Periodontitis is one of the most common bacterial infections in humans and is more prevalent in Non-Hispanic-Blacks as compared to Non-Hispanic Whites. This condition causes increased systemic inflammation, immune dysregulation, gut microbiota dysbiosis and thereby possibly influencing colorectal carcinogenesis. Periodontal-associated bacteria such as , and have been found in CRC tissues and in feces of CRC patients. Therefore, a deeper understanding of the association between oral and gastrointestinal bacterial profile, in addition to identifying prevalent bacteria in patients with CRC and the differences observed in ethnicity/race, may play a pivotal role in predicting incidence, prognosis, and lead to the development of new treatments.
PubMed: 35317317
DOI: 10.4251/wjgo.v14.i2.375 -
PloS One 2015Streptococcus gallolyticus subspecies gallolyticus (S. gallolyticus) can colonise the gastrointestinal tract of humans and animals and is known to cause similar...
Streptococcus gallolyticus subspecies gallolyticus (S. gallolyticus) can colonise the gastrointestinal tract of humans and animals and is known to cause similar infections in both humans and animals. Data about the spread or prevalence in farm animals are missing. In this study, Trypton Soya Agar was modified to a selective medium enabling the isolation and quantification of S. gallolyticus from faecal samples. The bacterium was observed in 82 out of 91 faecal samples obtained from 18 different organic turkey flocks. The prevalence of shedding birds was estimated by the number of positive fresh droppings and reached up to 100% on most farms. Furthermore, for the first time S. gallolyticus was quantified in faeces from poultry flocks. The median of colony forming units (CFU) per gramme faeces was 3.6 x 10(5) CFU/g. Typing of one isolate from each positive faecal sample by multilocus sequence typing delivered 24 sequence types (STs). Most of the isolates belonged to the clonal complex CC58. The same STs of this complex were detected in up to six different flocks. Partly, these flocks were located in various regions and stocked with varying breeding lines. Regarding the biochemical profiles of the same STs from different farms, the results did not contradict a spread of specific STs in the organic turkey production. Moreover, checking the pubMLST database revealed that STs found in this study were also found in other animal species and in humans. The high detection rate and the number of S. gallolyticus in turkey faeces indicate that this bacterium probably belongs to the common microbiota of the gastrointestinal tract of turkeys from organic flocks. Furthermore, the findings of this study support the suggestion of a possible interspecies transmission.
Topics: Animals; Bacterial Proteins; Cluster Analysis; Feces; Geography; Germany; Host-Pathogen Interactions; Multilocus Sequence Typing; Phylogeny; Poultry Diseases; Prevalence; Sequence Analysis, DNA; Species Specificity; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Streptococcal Infections; Streptococcus; Superoxide Dismutase; Turkeys
PubMed: 26657757
DOI: 10.1371/journal.pone.0144412 -
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 -
Scientific Reports Jan 2018Streptococcus gallolyticus subsp. gallolyticus (Sg) has long been reported to display a strong association with colorectal cancer (CRC). It was recently demonstrated to...
Streptococcus gallolyticus subsp. gallolyticus (Sg) has long been reported to display a strong association with colorectal cancer (CRC). It was recently demonstrated to actively promote the development of CRC, underscoring the importance of Sg in both clinical correlation and functional relevance in CRC. Here we investigated several clinical isolates of Sg in their interactions with human colon cancer cells and in mouse models. Some Sg strains were able to stimulate host cell proliferation (proliferation-promoting Sg, PP-Sg) whereas others were not (non-proliferation-promoting Sg, NP-Sg). PP-Sg strains adhered to colon cancer cells much better than NP-Sg strains, suggesting that close contact between Sg and host cells is important. In mice, PP-Sg is significantly better at colonizing the colon tissues of A/J mice compared to NP-Sg, however this difference was not observed in C57BL/6 mice, suggesting that Sg colonization of mouse colon tissues involves specific interactions between bacterial and host factors on the colonic epithelium. Finally, in an azoxymethane-induced mouse model of CRC, PP-Sg promoted tumor development whereas NP-Sg did not. These findings provide clues to the mechanism underlying the Sg-CRC association and have important implications to clinical studies that aim to correlate Sg with clinical and pathological features of CRC.
Topics: Animals; Cell Adhesion; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Disease Models, Animal; Epithelial Cells; Humans; Mice; Streptococcal Infections; Streptococcus gallolyticus subspecies gallolyticus
PubMed: 29367658
DOI: 10.1038/s41598-018-19941-7 -
Frontiers in Cellular and Infection... 2022subspecies () is an opportunistic pathogen causing invasive infections in the elderly often associated with colon neoplasia. The prevalence of in the stools of...
PURPOSE
subspecies () is an opportunistic pathogen causing invasive infections in the elderly often associated with colon neoplasia. The prevalence of in the stools of patients with normal colonoscopy (control) was compared with patients with colorectal adenomas (CRA) or with carcinomas (CRC) from stages I to IV. The presence of the s island encoding colibactin as well as other CRC-associated bacteria such as toxicogenic , , and was also investigated.
PATIENTS AND METHODS
Fecal samples collected in France between 2011 and 2016 from patients with normal colonoscopy ( = 25), adenoma ( = 23), or colorectal cancer at different stages ( = 81) were tested by PCR for the presence of , , , , and the island. Relative quantification of , , and in stools was performed by qPCR.
RESULTS
prevalence was significantly increased in the CRC group. Our results also revealed i) a strong and significant increase of toxinogenic in patients with early-stage adenoma and of island at late-stage CRC and ii) increased levels of and in the stools of CRC patients. Furthermore, the simultaneous detection of these five bacterial markers was only found in CRC patients.
CONCLUSIONS
Our results indicate that the prevalence or relative levels of CRC-associated bacteria vary during CRC development. Among them, (+) was singled out as the sole pathobiont detected at the early adenoma stage.
Topics: Aged; Bacteria; Bacterial Infections; Bacteroides fragilis; Carcinoma; Humans; Streptococcus gallolyticus
PubMed: 35360109
DOI: 10.3389/fcimb.2022.794391 -
Antimicrobial Agents and Chemotherapy Apr 2015The aim of this work was to characterize the antibiotic susceptibility and genetic diversity of 41 Streptococcus gallolyticus subsp. gallolyticus isolates: 18 isolates...
Streptococcus gallolyticus subsp. gallolyticus from human and animal origins: genetic diversity, antimicrobial susceptibility, and characterization of a vancomycin-resistant calf isolate carrying a vanA-Tn1546-like element.
The aim of this work was to characterize the antibiotic susceptibility and genetic diversity of 41 Streptococcus gallolyticus subsp. gallolyticus isolates: 18 isolates obtained from animals and 23 human clinical isolates. Antibiotic susceptibility was determined by the semiautomatic Wider system and genetic diversity by pulsed-field gel electrophoresis (PFGE) with SmaI. Animal isolates grouped separately in the PFGE analysis, but no statistical differences in antimicrobial resistance were found between the two groups. The LMG 17956 sequence type 28 (ST28) strain recovered from the feces of a calf exhibited high levels of resistance to vancomycin and teicoplanin (MIC, ≥256 mg/liter). Its glycopeptide resistance mechanism was characterized by Southern blot hybridization and a primer-walking strategy, and finally its genome, determined by whole-genome sequencing, was compared with four closely related S. gallolyticus subsp. gallolyticus genomes. Hybridization experiments demonstrated that a Tn1546-like element was integrated into the bacterial chromosome. In agreement with this finding, whole-genome sequencing confirmed a partial deletion of the vanY-vanZ region and partial duplication of the vanH gene. The comparative genomic analyses revealed that the LMG 17956 ST28 strain had acquired an unusually high number of transposable elements and had experienced extensive chromosomal rearrangements, as well as gene gain and loss events. In conclusion, S. gallolyticus subsp. gallolyticus isolates from animals seem to belong to lineages separate from those infecting humans. In addition, we report a glycopeptide-resistant isolate from a calf carrying a Tn1546-like element integrated into its chromosome.
Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Carbon-Oxygen Ligases; Cattle; Cattle Diseases; Chromosomes, Bacterial; Conjugation, Genetic; Feces; Genetic Variation; Genome, Bacterial; Humans; Microbial Sensitivity Tests; Plasmids; Streptococcal Infections; Streptococcus; Teicoplanin; Vancomycin Resistance
PubMed: 25605355
DOI: 10.1128/AAC.04083-14 -
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 -
Diagnostic Microbiology and Infectious... Nov 2023To develop an in-house matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) library for improved identification of species and...
OBJECTIVES
To develop an in-house matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) library for improved identification of species and subspecies of the Streptococcus bovis/Streptococcus equinus-complex (SBSEC).
METHODS
A total of 236 SBSEC isolates from blood stream infections and culture collections, determined by whole genome sequencing to subspecies level, were grown in brain heart infusion broth. Mass spectra were collected using the Bruker MALDI Biotyper system after ethanol-formic acid extraction. Main spectral profiles from 117 isolates were used to create the "SBSEC-CMRS library." The remaining 119 spectra were used for evaluation of Bruker MALDI Biotyper (MBT) Compass Library Revision K (2022) and the SBSEC-CMRS library.
RESULTS
The Bruker library correctly identified species and subspecies in 72 of 119 (61 %) isolates, while the SBSEC-CMRS library identified 116 of 119 (97 %), using a cutoff score of ≥2.0.
CONCLUSIONS
The SBSEC-CMRS library showed sufficient diagnostic accuracy, and can be implemented in clinical practice for SBSEC species and subspecies identification.
Topics: Humans; Streptococcus bovis; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Streptococcus
PubMed: 37598592
DOI: 10.1016/j.diagmicrobio.2023.116045