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Frontiers in Microbiology 2022is a zoonotic bacterial swine pathogen causing substantial economic and health burdens to the pork industry worldwide. Most genome sequences available in public...
is a zoonotic bacterial swine pathogen causing substantial economic and health burdens to the pork industry worldwide. Most genome sequences available in public databases are from isolates obtained outside the United States. We sequenced the genomes of 106 isolates from the U.S. and analyzed them to identify their potential to function as zoonotic agents and/or reservoirs for antimicrobial resistance (AMR) dissemination. The objective of this study was to evaluate the genetic diversity of isolates obtained within the U.S., for the purpose of screening for genomic elements encoding AMR and any factors that could increase or contribute to the capacity of to transmit, colonize, and/or cause disease in humans. Forty-six sequence types (STs) were identified with ST28 observed as the most prevalent, followed by ST87. Of the 23 different serotypes identified, serotype 2 was the most prevalent, followed by serotype 8 and 3. Of the virulence genes analyzed, the highest nucleotide diversity was observed in , , and . Tetracycline resistance was the most prevalent phenotypic antimicrobial resistance observed followed by macrolide-lincosamide-streptogramin B (MLSB) resistance. Numerous AMR elements were identified, many located within MGE sequences, with the highest frequency observed for , and . No genes encoding factors known to contribute to the transmission, colonization, and/or causation of disease in humans were identified in any of the genomes in this study. This includes the 89 K pathogenicity island carried by the virulent isolates responsible for human infections. Collectively, the data reported here provide a comprehensive evaluation of the genetic diversity among U.S. isolates. This study also serves as a baseline for determining any potential risks associated with occupational exposure to these bacteria, while also providing data needed to address public health concerns.
PubMed: 36439859
DOI: 10.3389/fmicb.2022.1043529 -
Journal of Clinical Microbiology Sep 2023an emerging zoonotic pathogen, causes invasive infections and substantial economic losses in the pig industry worldwide. Antimicrobial resistance against 22 antibiotics...
an emerging zoonotic pathogen, causes invasive infections and substantial economic losses in the pig industry worldwide. Antimicrobial resistance against 22 antibiotics was studied for 200 . strains collected in different geographical regions of France. Most of the strains (86%) showed resistance to at least one antibiotic with a low rate of resistance to fluoroquinolones, penicillins, pleuromutilin, and diaminopyrimidine-sulfonamides, and a higher rate to macrolides-lincosamides and tetracycline. Multi-resistance patterns were observed in 138 strains; three of them being resistant to six antibiotic families. Statistical analyses highlighted a decrease in the resistance to trimethoprim-sulfamethoxazole, in our collection, between the two periods studied-before 2010 and after 2015-as well as an impact of the geographical origin with a higher rate of resistance to macrolides-lincosamides and penicillin in Brittany than in the other French regions. Furthermore, macrolides-lincosamides and tetracycline resistance patterns were more likely to be found in pig isolates than in human and wild boar isolates. A difference in resistance was also observed between serotypes. Most of the penicillin-resistant strains belong to serotypes 1, 5, 9, 11, 12, 15, 27, and 29. Finally, penicillin and pleuromutilin resistances were mostly found in "non-clinical" isolates. The empirical treatment of human and porcine infections due to in France can therefore still be carried out with beta-lactams. However, this study emphasizes the need to monitor antimicrobial resistance in this zoonotic pathogen.
Topics: Humans; Animals; Swine; Anti-Bacterial Agents; Streptococcus suis; Drug Resistance, Bacterial; Penicillins; France; Lincosamides; Macrolides; Sus scrofa; Pleuromutilins
PubMed: 37655935
DOI: 10.1128/jcm.00164-23 -
Veterinary Microbiology Aug 2021Streptococcus suis is a zoonotic pathogen that can cause invasive infections in humans and pigs. The S. suis cps31 strains (SS31) were frequently isolated from healthy...
Streptococcus suis is a zoonotic pathogen that can cause invasive infections in humans and pigs. The S. suis cps31 strains (SS31) were frequently isolated from healthy or diseased pigs and one human infection case caused by SS31 was reported in Thailand in 2015. However, except for a few epidemiologic studies, little information is available for SS31. To characterize SS31, a total of 75 SS31 strains were analyzed, including 52 strains that were isolated from healthy or diseased pigs and 23 strains whose information was accessed from NCBI. The MLST analysis showed that SS31 exhibited high heterogeneity. The phylogenetic analysis and minimum core-genome (MCG) classification revealed that 75 strains were clustered into 3 lineages. Strains from NCBI mainly at Lineage 2 belong to MCG7-3, and most of strains from China at Lineage 3 belong to MCG7-2. This finding indicated that their evolutionary path was different. All SS31 strains were resistant to more than three classes of antimicrobial agents, and major antimicrobial resistance genes for strains from Lineage 3 were carried by prophages. This observation is different from the previous observation that integrative conjugative elements and integrative and mobilizable elements are major vehicles of antimicrobial resistance genes for S. suis. In addition to strains isolated from diseased pigs, seven of 47 strains isolated from clinically healthy pigs were also pathogenic in a zebrafish infection model. These findings reveal unique characteristics of SS31 and contribute to establishing public health surveillance for SS31 and clarifying the diversity of S. suis.
Topics: Animals; Anti-Bacterial Agents; Drug Resistance, Multiple, Bacterial; Evolution, Molecular; Genotype; Mice; Mice, Inbred BALB C; Microbial Sensitivity Tests; Multilocus Sequence Typing; Phylogeny; Streptococcal Infections; Streptococcus suis; Swine; Swine Diseases; Virulence; Zebrafish
PubMed: 34147764
DOI: 10.1016/j.vetmic.2021.109149 -
Veterinary Research Jan 2023Streptococcus suis serotype 2 is an important bacterial pathogen of swine, responsible for substantial economic losses to the swine industry worldwide. The knowledge on...
Streptococcus suis serotype 2 is an important bacterial pathogen of swine, responsible for substantial economic losses to the swine industry worldwide. The knowledge on the pathogenesis of the infection caused by S. suis is still poorly known. It has been previously described that S. suis possesses at least one lipoprotein with double laminin and zinc (Zn)-binding properties, which was described in the literature as either laminin-binding protein (Lmb, as in the current study), lipoprotein 103, CDS 0330 or AdcAII. In the present study, the role of the Lmb in the pathogenesis of the infection caused by S. suis serotype 2 was dissected. Using isogenic mutants, results showed that Lmb does not play an important role in the laminin-binding activity of S. suis, even when clearly exposed at the bacterial surface. In addition, the presence of this lipoprotein does not influence bacterial adhesion to and invasion of porcine respiratory epithelial and brain endothelial cells and it does not increase the susceptibility of S. suis to phagocytosis. On the other hand, the Lmb was shown to play an important role as cytokine activator when tested in vitro with dendritic cells. Finally, this lipoprotein plays a critical role in Zn acquisition from the host environment allowing bacteria to grow in vivo. The significant lower virulence of the Lmb defective mutant may be related to a combination of a lower bacterial survival due to the incapacity to acquire Zn from their surrounding milieu and a reduced cytokine activation.
Topics: Animals; Swine; Laminin; Streptococcus suis; Serogroup; Cytokines; Endothelial Cells; Zinc; Streptococcal Infections; Swine Diseases
PubMed: 36604750
DOI: 10.1186/s13567-022-01128-8 -
Antibiotics (Basel, Switzerland) Feb 2022() causes severe respiratory diseases in pigs and is also an important pathogen causing hidden dangers to public health and safety. Acetylkitasamycin is a new macrolide...
() causes severe respiratory diseases in pigs and is also an important pathogen causing hidden dangers to public health and safety. Acetylkitasamycin is a new macrolide agent that has shown good activity to Gram-positive cocci such as The purpose of this study was to perform pharmacokinetic-pharmacodynamic (PK-PD) modeling to formulate a dosing regimen of acetylkitasamycin for treatment of and to decrease the emergence of acetylkitasamycin-resistant . The minimal inhibitory concentration (MIC) of 110 isolates was determined by broth micro dilution method. The MIC of the 55 sensitive isolates was 1.21 μg/mL. The strain HB1607 with MIC close to MIC and high pathogenicity was used for the PK-PD experiments. The MIC and MBC of HB1607 in both MH broth and pulmonary epithelial lining fluid (PELF) was 1 and 2 μg/mL, respectively. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was used to determine the concentration change of acetylkitasamycin in piglet plasma and PELF after intragastric administration of a single dose of 50 mg/kg b.w. acetylkitasamycin. The PK parameters were calculated by WinNolin software. The PK data showed that the maximum concentration (C), peak time (T), and area under the concentration-time curve (AUC) were 9.84 ± 0.39 μg/mL, 4.27 ± 0.19 h and 248.58 ± 21.17 h·μg/mL, respectively. Integration of the in vivo PK data and ex vivo PD data, an inhibition sigmoid E equation was established. The dosing regimen of acetylkitasamycin for the treatment infection established as 33.12 mg/kg b.w. every 12 h for 3 days. This study provided a reasonable dosing regimen for a new drug used in clinical treatment, which can effectively be used to treat infection and slow down the generation of drug resistance.
PubMed: 35203885
DOI: 10.3390/antibiotics11020283 -
Journal of Applied Microbiology Jun 2020The aim of this study is to investigate Streptococcus suis strains present in Jiangsu province, China.
AIMS
The aim of this study is to investigate Streptococcus suis strains present in Jiangsu province, China.
METHODS AND RESULTS
In all, 1650 nasal and anal swab samples and 100 tonsils were collected from clinically healthy swine. Culture characteristics, colony morphology and PCR-based analysis of the glutamate dehydrogenase (gdh) gene were performed for S. suis identification, and eight isolates were confirmed to be S. suis. The isolates serogroups were identified by agglutinating test, including 4, 7, 3, 5 and 8. Gene profiling by PCR showed that the manN, purD, orf2, gdh genes were conserved among the isolates and that 50% of the isolates carried dltA, pgdA, srtA and sspA. Antimicrobial susceptibility test showed the isolates displayed resistance to clindamycin, erythromycin, tetracycline, penicillin G, vancomycin and linezolid; while none was resistant to chloramphenicol, multi-drug resistance was seen in most of the isolates. Finally, the LD (assessed by zebrafish) of isolates RD105 was 2·6431 × 10 and HA24 was 7·1198 × 10 , which showed RD105 more virulent and was consistent with the results of virulence factor identification.
CONCLUSIONS
There is a very low proportion of S. suis in the healthy pigs. The virulence factors were related to pathogenicity. Bacteria in Nantong possess greater virulence potential than those in Huaian.
SIGNIFICANCE AND IMPACT OF THE STUDY
Systematic investigation of S. suis provided the most basic theoretical support for the prevention and control of swine streptococcosis.
Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; China; Drug Resistance, Bacterial; Microbial Sensitivity Tests; Serogroup; Streptococcal Infections; Streptococcus suis; Swine; Swine Diseases; Virulence; Virulence Factors
PubMed: 31981255
DOI: 10.1111/jam.14591 -
Pathogens (Basel, Switzerland) Mar 2023, both a common colonizer of the porcine upper respiratory tract and an invasive pig pathogen, successfully adapts to different host environments encountered during... (Review)
Review
, both a common colonizer of the porcine upper respiratory tract and an invasive pig pathogen, successfully adapts to different host environments encountered during infection. Whereas the initial infection mainly occurs via the respiratory tract, in a second step, the pathogen can breach the epithelial barrier and disseminate within the whole body. Thereby, the pathogen reaches other organs such as the heart, the joints, or the brain. In this review, we focus on the role of metabolism for adaptation to these different in vivo host niches to encounter changes in nutrient availability, host defense mechanisms and competing microbiota. Furthermore, we highlight the close link between metabolism and virulence. Mutants deficient in metabolic regulators often show an attenuation in infection experiments possibly due to downregulation of virulence factors, reduced resistance to nutritive or oxidative stress and to phagocytic activity. Finally, metabolic pathways as potential targets for new therapeutic strategies are discussed. As antimicrobial resistance in isolates has increased over the last years, the development of new antibiotics is of utmost importance to successfully fight infections in the future.
PubMed: 37111427
DOI: 10.3390/pathogens12040541 -
Biomedicine & Pharmacotherapy =... Dec 2023Antimicrobial resistance is a worldwide problem that urges novel alternatives to treat infections. In attempts to find novel molecules, we assess the antimicrobial...
Essential oils of Pinus sylvestris, Citrus limon and Origanum vulgare exhibit high bactericidal and anti-biofilm activities against Neisseria gonorrhoeae and Streptococcus suis.
Antimicrobial resistance is a worldwide problem that urges novel alternatives to treat infections. In attempts to find novel molecules, we assess the antimicrobial potential of seven essential oils (EO) of different plants (Pinus sylvestris, Citrus limon, Origanum vulgare, Cymbopogon martini, Cinnamomum cassia, Melaleuca alternifolia and Eucalyptus globulus) against two multidrug-resistant bacteria species, i.e. Neisseria gonorrhoeae and Streptococcus suis. EOs of P. sylvestris and C. limon revealed higher bactericidal activity (MIC ≤ 0.5 mg/mL) and capacity to rapidly disperse biofilms of several N. gonorrhoeae clinical isolates than other EOs. Examination of biofilms exposed to both EO by electron microscopy revealed a reduction of bacterial aggregates, high production of extracellular vesicles, and alteration of cell integrity. This activity was dose-dependent and was enhanced in DNase I-treated biofilms. Antibiotic susceptibility studies confirmed that both EOs affected the outer membrane permeability, and analysis of EO- susceptibility of an LPS-deficient mutant suggested that both EO target the LPS bilayer. Further analysis revealed that α- and β-pinene and d-limonene, components of both EO, contribute to such activity. EO of C. martini, C. cassia, and O. vulgare exhibited promising antimicrobial activity (MIC ≤ 0.5 mg/mL) against S. suis, but only EO of O. vulgare exhibited a high biofilm dispersal activity, which was also confirmed by electron microscopy studies. To conclude, the EO of P. sylvestris, C. limon and O. vulgare studied in this work exhibit bactericidal and anti-biofilm activities against gonococcus and streptococcus, respectively.
Topics: Oils, Volatile; Neisseria gonorrhoeae; Pinus sylvestris; Origanum; Streptococcus suis; Citrus; Lipopolysaccharides; Anti-Bacterial Agents; Anti-Infective Agents; Biofilms; Microbial Sensitivity Tests
PubMed: 37857249
DOI: 10.1016/j.biopha.2023.115703 -
Journal of Applied Microbiology Aug 2021This study aimed to explore potential drug targets of Streptococcus suis at the system level.
AIMS
This study aimed to explore potential drug targets of Streptococcus suis at the system level.
METHODS AND RESULTS
A homologous protein mapping method was used in the construction of a protein-protein interaction (PPI) network of S. suis, which presented 1147 non-redundant interaction pairs among 286 proteins. The parameters of PPI networks were calculated and showed scale-free network properties. In all, 41 possibly essential proteins identified from 47 highly connected proteins were selected as potential drug target candidates. Of these proteins, 30 were already regarded as drug targets in other bacterial species. Six transporters with high connections to other functional proteins were identified as probably not essential but important functional proteins. Afterward, the subnetwork centred with cell division protein FtsZ was used in confirming the PPI network through bacterial two-hybrid analysis.
CONCLUSIONS
The predicted PPI network covers 13·04% of the proteome in S. suis. The selected 41 potential drug target candidates are conserved between S. suis and several model bacteria.
SIGNIFICANCE AND IMPACT OF THE STUDY
The predictions included proteins known to be drug targets, and a verifying experiment confirmed the reliability of predicted interactions. This work is the first to present systematic computational PPI data for S. suis and provides potential drug targets, which are valuable in exploring novel anti-streptococcus drugs.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Membrane Transport Proteins; Protein Interaction Mapping; Proteome; Streptococcus suis
PubMed: 33249680
DOI: 10.1111/jam.14950 -
Pathogens (Basel, Switzerland) Oct 2021represents a primary health problem (such as meningitis, septicemia and arthritis in piglets and fatteners) in the swine industry worldwide and also an emerging...
represents a primary health problem (such as meningitis, septicemia and arthritis in piglets and fatteners) in the swine industry worldwide and also an emerging zoonotic pathogen. In the Czech Republic, many pig farms repopulated their herds over the past decades to reduce morbidity and minimize treatment. The study analysed serotypes, sequence types and antimicrobial susceptibility in 39 isolates obtained from organs of diseased pigs from selected 16 repopulated farms with a history of -associated diseases and routine antimicrobial treatment with tulathromycin and/or amoxicillin. The analysis revealed diversity of collected isolates with regular occurrence of more than three serotypes per farm. The serotypes identified were 1/2 and 7, each in six isolates, followed by serotype 2 and 3 found in five isolates each, other serotypes were less frequent. Seven isolates were not typable by multiplex PCR and we also found sequence type of unknown type in thirteen isolates. The majority of isolates were resistant to clindamycin (n = 31), tetracycline (n = 29) and tilmicosin and tulathromycin (n = 28). On the other hand, with the exception of two isolates that were intermediately susceptible to penicillin and ampicillin, all isolates were susceptible to all three tested subgroups of beta-lactam antibiotics.
PubMed: 34684263
DOI: 10.3390/pathogens10101314