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Journal of Dairy Science Nov 2023Staphylococcus chromogenes and Staphylococcus simulans are commonly found in intramammary infections (IMI) associated with bovine subclinical mastitis, but little is...
Staphylococcus chromogenes and Staphylococcus simulans are commonly found in intramammary infections (IMI) associated with bovine subclinical mastitis, but little is known about genotypic variation and relatedness within species. This includes knowledge about genes encoding antimicrobial resistance (AMR) and potential virulence factors (pVF). The aim of this study was therefore to investigate these aspects by whole-genome sequencing of milk isolates from Swedish dairy cows with subclinical mastitis in an observational study. We also wanted to study if specific genotypes were associated with persistent IMI and the inflammatory response at udder quarter level. In total, 105 and 118 isolates of S. chromogenes and S. simulans, respectively, were included. Isolates were characterized using a 7-locus multilocus sequence typing (7-MLST), core genome analysis and in-silico analysis of AMR and pVF genes. Forty-seven sequence types (ST) and 7 core genome clusters of S. chromogenes were identified, and the most common ST were ST-6 and ST-109, both belonging to cluster VII. A 7-locus MLST scheme for S. simulans was not available, but 3 core genome clusters and 5 subclusters were described. Overall, substantial variation in ST and clusters among cows and herds were found in both species. Some ST of S. chromogenes were found in several herds, indicating spread between herds. Moreover, within-herd spread of the same genotype was observed for both species. Only a few AMR genes [blaZ, strpS194, vga(A)] were detected in a limited number of isolates, with the exception of blaZ coding for β-lactamase, which was identified in 22% of the isolates of S. chromogenes with ST-19, ST-102, and ST-103 more commonly carrying this gene compared with other ST. However, the blaZ gene was not identified in S. simulans. The average total number of pVF detected per isolate was similar in S. chromogenes (n = 30) and S. simulans (n = 33), but some variation in total numbers and presence of specific pVF or functional groups of pVF, was shown between ST/clusters within species. Differences in inflammatory response and potentially in persistent IMI at udder quarter level were found between S. chromogenes subtypes but not between S. simulans subtypes. In conclusion, the results from the present study generates new insight into the epidemiology of bovine S. chromogenes and S. simulans IMI, which can have implications for future prevention and antimicrobial treatment of infections related to these species.
PubMed: 37641317
DOI: 10.3168/jds.2023-23523 -
AIMS Microbiology 2021Lysostaphin is a glycylglycine endopeptidase, secreted by , capable of specifically hydrolyzing pentaglycine crosslinks present in the peptidoglycan of the cell wall....
Lysostaphin is a glycylglycine endopeptidase, secreted by , capable of specifically hydrolyzing pentaglycine crosslinks present in the peptidoglycan of the cell wall. In this paper, we describe the cloning and expression of the lysostaphin enzyme gene in WB600 host using pWB980 expression system. Plasmid pACK1 of was extracted using the alkaline lysis method. Lysostaphin gene was isolated by PCR and cloned into pTZ57R/T-Vector, then transformed into DH5α. The amplified gene fragment and uncloned pWB980 vector were digested using I and І enzymes and purified. The restricted gene fragment was ligated into the pWB980 expression vector by the standard protocols, then the recombinant plasmid was transformed into WB600 using electroporation method. The recombinant protein was evaluated by the SDS-PAGE method and confirmed by western immunoblot. Analysis of the target protein showed a band corresponding to 27-kDa r-lysostaphin. Protein content was estimated 91 mg/L by Bradford assay. The recombinant lysostaphin represented 90% of its maximum activity at 40 °C and displayed good thermostability by keeping about 80% of its maximum activity at 45 °C. Heat residual activity assay of recombinant lysostaphin demonstrated that the enzyme stability was up to 40 °C and showed good stability at 40 °C for 16 h incubation.
PubMed: 34708172
DOI: 10.3934/microbiol.2021017 -
IDCases 2021Urinary tract infections (UTIs) are clinically and economically burdensome. Gram positive causative uropathogens are rare, and has infrequently been isolated as a...
Urinary tract infections (UTIs) are clinically and economically burdensome. Gram positive causative uropathogens are rare, and has infrequently been isolated as a causative agent for UTIs. Here, we present two cases of causing complicated urinary tract infections.
PubMed: 34195001
DOI: 10.1016/j.idcr.2021.e01202 -
Microbes and Infection Feb 2017Humans and animals are colonized by members of the genus Staphylococcus, however only some of these species evolved to cause invasive disease. The genetic basis for...
Humans and animals are colonized by members of the genus Staphylococcus, however only some of these species evolved to cause invasive disease. The genetic basis for conversion of commensal staphylococci into pathogens is not known. We hypothesized that Staphylococcus aureus genes for coagulation and agglutination in vertebrate blood (coa, vwb and clfA) may support pathogenic conversion. Expression of coa and vwb in Staphylococcus epidermidis or Staphylococcus simulans supported a coagulase-positive phenotype but not the ability to cause disease in a mouse model of bloodstream infection. However, the simultaneous expression of coa, vwb and clfA in coagulase-negative staphylococci enabled bacterial agglutination in plasma and enhanced survival of S. simulans in human whole blood. Agglutination of S. simulans in the bloodstream of infected mice upon expression of coa, vwb and clfA provided also a mean for dissemination and replication in distal organs. Thus, the acquisition of genes for bacterial agglutination with fibrin appear sufficient for the conversion of commensal staphylococci into invasive pathogens.
Topics: Animals; Bacteremia; Coagulase; Disease Models, Animal; Female; Mice, Inbred BALB C; Staphylococcus; Virulence; Virulence Factors
PubMed: 28012900
DOI: 10.1016/j.micinf.2016.12.002 -
Journal of Dairy Science Jul 2017Non-aureus staphylococci (NAS), the microorganisms most frequently isolated from bovine milk worldwide, are a heterogeneous group of numerous species. To establish their...
Non-aureus staphylococci (NAS), the microorganisms most frequently isolated from bovine milk worldwide, are a heterogeneous group of numerous species. To establish their importance as a group, the distribution of individual species needs to be determined. In the present study, NAS intramammary infection (IMI) was defined as a milk sample containing ≥1,000 cfu/mL in pure or mixed culture that was obtained from a cohort of cows assembled by the Canadian Bovine Mastitis Research Network. Overall, 6,213 (6.3%) of 98,233 quarter-milk samples from 5,149 cows and 20,305 udder quarters were associated with an NAS IMI. Of the 6,213 phenotypically identified NAS isolates, 5,509 (89%) were stored by the Canadian Bovine Mastitis Research Network Mastitis Pathogen Collection and characterized using partial sequencing of the rpoB housekeeping gene, confirming 5,434 isolates as NAS. Prevalence of each NAS species IMI was estimated using Bayesian models, with presence of a specific NAS species as the outcome. Overall quarter-level NAS IMI prevalence was 26%. The most prevalent species causing IMI were Staphylococcus chromogenes (13%), Staphylococcus simulans (4%), Staphylococcus haemolyticus (3%), Staphylococcus xylosus (2%), and Staphylococcus epidermidis (1%). The prevalence of NAS IMI as a group was highest in first-parity heifers and was evenly distributed throughout cows in parities ≥2. The IMI prevalence of some species such as S. chromogenes, S. simulans, and S. epidermidis differed among parities. Overall prevalence of NAS IMI was 35% at calving, decreased over the next 10 d, and then gradually increased until the end of lactation. The prevalence of S. chromogenes, Staphylococcus gallinarum, Staphylococcus cohnii, and Staphylococcus capitis was highest at calving, whereas the prevalence of S. chromogenes, S. haemolyticus, S. xylosus, and S. cohnii increased during lactation. Although the overall prevalence of NAS IMI was similar across barn types, the prevalence of S. simulans, S. xylosus, S. cohnii, Staphylococcus saprophyticus, S. capitis, and Staphylococcus arlettae IMI was higher in tiestall barns; the prevalence of S. epidermidis IMI was lowest; and the prevalence of S. chromogenes and Staphylococcus sciuri IMI was highest in bedded-pack barns. Staphylococcus simulans, S. epidermidis, S. xylosus, and S. cohnii IMI were more prevalent in herds with intermediate to high bulk milk somatic cell count (BMSCC) and S. haemolyticus IMI was more prevalent in herds with high BMSCC, whereas other common NAS species IMI were equally prevalent in all 3 BMSCC categories. Distribution of NAS species IMI differed among the 4 regions of Canada. In conclusion, distribution differed considerably among NAS species IMI; therefore, accurate identification (species level) is essential for studying NAS epidemiology.
Topics: Animals; Bayes Theorem; Canada; Cattle; Cattle Diseases; Female; Mammary Glands, Animal; Mastitis, Bovine; Milk; Pregnancy; Prevalence; Species Specificity; Staphylococcal Infections; Staphylococcus
PubMed: 28527793
DOI: 10.3168/jds.2016-12478 -
Antimicrobial Agents and Chemotherapy May 2020Recent studies highlight the abundance of commensal agulase-egative taphylococci (CoNS) on healthy skin. Evidence suggests that CoNS actively shape the skin...
Recent studies highlight the abundance of commensal agulase-egative taphylococci (CoNS) on healthy skin. Evidence suggests that CoNS actively shape the skin immunological and microbial milieu to resist colonization or infection by opportunistic pathogens, including methicillin-resistant (MRSA), in a variety of mechanisms collectively termed colonization resistance. One potential colonization resistance mechanism is the application of quorum sensing, also called the ccessory ene egulator () system, which is ubiquitous among staphylococci. Common and rare CoNS make autoinducing peptides (AIPs) that function as MRSA inhibitors, protecting the host from invasive infection. In a screen of CoNS spent media, we found that , a rare human skin colonizer and frequent livestock colonizer, released potent inhibitors of all classes of MRSA signaling. We identified three classes and have shown intraspecies cross talk between noncognate types for the first time. The AIP-I structure was confirmed, and the novel AIP-II and AIP-III structures were solved via mass spectrometry. Synthetic AIPs inhibited MRSA signaling with nanomolar potency. in competition with MRSA reduced dermonecrotic and epicutaneous skin injury in murine models. The addition of synthetic AIP-I also effectively reduced MRSA dermonecrosis and epicutaneous skin injury in murine models. These results demonstrate potent anti-MRSA quorum sensing inhibition by a rare human skin commensal and suggest that cross talk between CoNS and MRSA may be important in maintaining healthy skin homeostasis and preventing MRSA skin damage during colonization or acute infection.
Topics: Animals; Bacterial Proteins; Humans; Methicillin-Resistant Staphylococcus aureus; Mice; Peptides; Quorum Sensing; Staphylococcal Infections; Staphylococcus
PubMed: 32253213
DOI: 10.1128/AAC.00172-20 -
Nutrients Dec 2022Proteases, especially microbial proteases, are widely used in food processing. The purpose of this study was aimed to purify an extracellular protease produced by the...
Proteases, especially microbial proteases, are widely used in food processing. The purpose of this study was aimed to purify an extracellular protease produced by the strain QB7 and to evaluate its ability in hydrolyzing meat proteins and generating antioxidant and anti-inflammatory peptides. The optimal conditions for producing the enzyme were as follows: inoculum ratio, 10%; initial pH, 6.5; temperature, 32 °C; incubation time, 36 h; and rotation speed, 160 rpm. The protease had a molecular weight of approximately 47 kDa, possessing the optimal activity at 50 °C, pH 7.0, The protease was stable at pH 4.0-8.0 and 30-60 °C, and the activity was improved by Na, Mg, Ca, and Zn ions, whereas it was inhibited by Cu, Co, Fe, Ba, Fe, β-M, and ethylene diamine tetraacetic acid disodium salt (EDTA). The protease could effectively hydrolyze meat proteins, and the generated hydrolysate could significantly inhibit tumor necrosis factor-alpha (TNFα)-induced oxidative stress, including superoxide and malondialdehyde levels and inflammation (vascular adhesion molecule-1 [VCAM-1] and cyclooxygenase 2 [COX2)) in human vascular EA.hy926 cells. The present findings support the ability of QB7 protease in generating antioxidant and anti-inflammatory peptides during the fermentation of meat products.
Topics: Humans; Peptide Hydrolases; Antioxidants; Meat Proteins; Endopeptidases; Peptides; Anti-Inflammatory Agents; Hydrogen-Ion Concentration
PubMed: 36615723
DOI: 10.3390/nu15010065 -
BMJ Case Reports May 2021A 78-year-old man with an implantable cardioverter-defibrillator (ICD) presented with chills and malaise. His history was significant for heart failure with reduced...
A 78-year-old man with an implantable cardioverter-defibrillator (ICD) presented with chills and malaise. His history was significant for heart failure with reduced ejection fraction and complete heart block. He had undergone permanent pacemaker placement that was later upgraded to an ICD 5 years before his presentation. Physical examination revealed an open wound with surrounding erythema overlying the device site. Blood cultures obtained on admission were negative. Transesophageal echocardiogram did not show valve or lead vegetations. He underwent a prolonged extraction procedure. Postoperatively, he developed septic shock and cultures from the device, and repeat peripheral blood cultures grew and He was treated with intravenous vancomycin but had refractory hypotension, leading to multiorgan failure. He later expired after being transitioned to comfort care. The patient may have acquired by feeding cows on a nearby farm, and the prolonged extraction procedure may have precipitated the bacteraemia.
Topics: Aged; Animals; Bacteremia; Cattle; Defibrillators, Implantable; Humans; Male; Sepsis; Staphylococcus
PubMed: 34045192
DOI: 10.1136/bcr-2020-240309 -
Journal of Dairy Science Sep 2014The aim of this review is to assess the effect of coagulase-negative staphylococci (CNS) species on udder health and milk yield in ruminants, and to evaluate the... (Review)
Review
The aim of this review is to assess the effect of coagulase-negative staphylococci (CNS) species on udder health and milk yield in ruminants, and to evaluate the capacity of CNS to cause persistent intramammary infections (IMI). Furthermore, the literature on factors suspected of playing a role in the pathogenicity of IMI-associated CNS, such as biofilm formation and the presence of various putative virulence genes, is discussed. The focus is on the 5 CNS species that have been most frequently identified as causing bovine IMI using reliable molecular identification methods (Staphylococcus chromogenes, Staphylococcus simulans, Staphylococcus haemolyticus, Staphylococcus xylosus, and Staphylococcus epidermidis). Although the effect on somatic cell count and milk production is accepted to be generally limited or nonexistent for CNS as a group, indications are that the typical effects differ between CNS species and perhaps even strains. It has also become clear that many CNS species can cause persistent IMI, contrary to what has long been believed. However, this trait appears to be quite complicated, being partly strain dependent and partly dependent on the host's immunity. Consistent definitions of persistence and more uniform methods for testing this phenomenon will benefit future research. The factors explaining the anticipated differences in pathogenic behavior appear to be more difficult to evaluate. Biofilm formation and the presence of various staphylococcal virulence factors do not seem to (directly) influence the effect of CNS on IMI but the available information is indirect or insufficient to draw consistent conclusions. Future studies on the effect, persistence, and virulence of the different CNS species associated with IMI would benefit from using larger and perhaps even shared strain collections and from adjusting study designs to a common framework, as the large variation currently existing therein is a major problem. Also within-species variation should be investigated.
Topics: Animals; Biofilms; Cattle; Coagulase; Female; Mammary Glands, Animal; Mastitis, Bovine; Milk; Phenotype; Species Specificity; Staphylococcal Infections; Staphylococcus; Virulence Factors
PubMed: 24952781
DOI: 10.3168/jds.2013-7775 -
Central European Journal of Public... Jun 2022This work aimed to determine the representation and resistance of bacteria belonging to the genus Staphylococcus and Enterococcus on inanimate surfaces of two selected...
OBJECTIVES
This work aimed to determine the representation and resistance of bacteria belonging to the genus Staphylococcus and Enterococcus on inanimate surfaces of two selected workplaces of the University Hospital of L. Pasteur in Košice (UHLP) and to investigate their importance in the hospital environment. The men's ward of the Department of Internal Medicine (DIM) and the Department of Anaesthesiology and Intensive Care (DAIC) were chosen.
METHODS
Using sterile sampling kits, a total of 182 swabs were collected from the inanimate surfaces of both UHLP workplaces. The swabs were then transported to a microbiological laboratory and inoculated onto sterile culture media (blood agar containing 5% ram erythrocytes). After culturing (24-48 hours, in a thermostat at constant temperature 37 °C), bacterial colonies were identified by mass spectrometry on a MALDI TOF MS. Bacteria belonging to the genera Staphylococcus and Enterococcus were subsequently separated from the spectrum of identified bacteria. Nosocomial significant strains of staphylococci (Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus aureus) and all isolated enterococci were subjected to susceptibility testing for selected antibiotics using the disk diffusion method - E-tests.
RESULTS
Several members of the genus Staphylococcus were identified from the inanimate surfaces of both workplaces. These were mainly coagulase-negative strains - Staphylococcus epidermidis (45), Staphylococcus capitis (34), Staphylococcus haemolyticus (20), Staphylococcus hominis (45), Staphylococcus pasteuri (2), Staphylococcus sroph (1), Staphylococcus simulans (3), and Staphylococcus warneri (4). Staphylococcus aureus strains were also identified (2). Nosocomial significant isolates were tested for susceptibility to the antibiotics cefoxitin (FOX) and oxacillin (OXA). Two members of the genus Enterococcus - Enterococcus faecium (7) and Enterococcus faecalis (8) were isolated. All strains were subject to vancomycin susceptibility testing using the disk method.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Cross Infection; Enterococcus; Hospitals; Humans; Male; Microbial Sensitivity Tests; Sheep; Staphylococcal Infections; Staphylococcus
PubMed: 35841227
DOI: 10.21101/cejph.a7241