Abstract The purpose of this study was to evaluate the rate of detection of coagulase negative staphylococci (CoNS) in environmental samples of 17 services in a Tunisian hospital, determining the ...antimicrobial resistance phenotypes and genotypes of recovered isolates. To our knowledge, this is the first study that determines the prevalence of CoNS with correlation of antibiotic resistance in the hospital environment in Tunisia. CoNS were obtained from 83 of the 200 tested samples (41.5%). Staphylococcus haemolyticus was the most prevalent species (45.8%), followed by S. saprophyticus (36.1%). The remaining CoNS species detected were S. epidermidis, S. cohnii, S. warneri, S. sciuri, S. simulans, S. pasteuri, S. arlettae , and S. xilosus . Methicillin-resistant CoNS were detected in 20 of the 200 tested samples (10%), and the mec A gene was demonstrated in 18 S. haemolyticus , one S. epidermidis and one S. saprophyticus isolates. Methicillin susceptible isolates were detected in 63 samples (31.5%). Antimicrobial resistance genes detected were as follows (number of isolates): erythromycin msr (A) (n = 32); erm (C) (n = 8), tetracycline tet (K) and/or tet (M) (n = 21), gentamicin aac (6′)-Ie- aph (2″)-Ia (n = 16), kanamycin ( aph (3′)-IIIa (n = 19), tobramycin ant (4′)-Ia (n = 14), and streptomycin ant (6′)-Ia (n = 3). The high frequency of detection of multi-drug-resistant CoNS in the hospital environment, especially S. haemolyticus and S. saprophyticus , is of relevance and could be due to cross-transmission between patients, staff, and environment.
Coagulase-negative staphylococci (CoNS), originally described as ubiquitous commensals of the healthy human skin and mucosa, have emerged as important opportunistic pathogens primarily causing ...healthcare-associated infections in patients with indwelling medical devices. Recent studies, utilizing new molecular typing methods, particularly on
Staphylococcus epidermidis
, have increased our understanding of the mechanisms that contribute to the evolutionary success of these extremely versatile microorganisms. In the following mini-review, we summarize recent research in this area focusing on the molecular methods and epidemiology of
S. epidermidis
and
S. saprophyticus
.
Cementation of salt-containing soils can be achieved by salt-tolerant or halophilic calcite precipitation bacteria. Therefore, the isolation of calcite-producing bacteria in the presence of salt is ...the first step in the microbial cementation of saline soils. Urease producing bacteria can cause calcite nano-crystals to precipitate by producing urease in the presence of urea and calcium. The purpose of this study was to isolate urease producing halophilic bacteria in order to make calcite precipitate in saline soil. The calcite and the properties of the strains were further analyzed by X-ray diffraction (XRD) and scanning electron microscope equipped with an energy dispersive X-ray detector. In this study, a total of 110 halophilic strains were isolated, from which 58 isolates proved to have the ability of urease production. Four strains were identified to produce nano-calcite using urease activity in the precipitation medium. The XRD studies showed that the size of these particles was in the range of 40–60 nm. Strain H3 revealed that calcite is mostly produced in the precipitation medium containing 5% salt in comparison with other strains. This strain also produced calcite precipitates in the precipitation medium containing 15% salt. Phylogenetic analysis indicated that these isolates are about 99–100% similar to
Staphylococcus saprophyticus
.
Staphylococcus saprophyticus is a gram-positive microorganism responsible for urinary tract infections (UTIs). Although some virulence factors are characterized, such as urease, autolysins, adhesins ...and hemagglutinins, large-scale proteomic studies have not been performed within this species. We performed the characterization of the exoproteome from three S. saprophyticus strains: the reference strain ATCC 15,305, a non-capsular strain 7108 and the 9325 strain containing a thick capsule which were cultured in BHI medium and culture supernatants were analysed by using mass spectrometry approach. We observed a core of 72 secreted proteins. In addition, it was possible to detect diversity in the protein profiles of the exoproteomes. Interestingly, strain 7108 presented no secretion of three antigenic proteins, including the classical SsaA antigen. In addition, the level of antigenic proteins secreted by strain 9325 was higher than in ATCC 15,305. This result was confirmed by Western blot analysis using anti-SsaA polyclonal antibodies, and no production/ secretion of SsaA was detected in strain 7108. Transcriptional data shows that 7108 strain produces transcripts encoding SsaA, suggesting post-transcriptional regulation occurs in this strain. Moreover, when compared with the other strains that were analyzed, it was possible to detect higher levels of proteases secreted by strain 7108 and higher levels of antigenic proteins and transglycosylases secreted by 9325 strain. The results reveal diversity in protein secretion among strains. This research is an important first step towards understanding the variability in S. saprophyticus exoproteome profile and could be significant in explaining differences among strains.
Aims
Urease is a key virulence factor for the Gram‐positive urinary tract pathogen Staphylococcus saprophyticus and a potential target for antimicrobial therapy. The enzyme from S. saprophyticus is ...unusual in that it does not contain cysteine at the active site. The aims of this study were to test 14 over‐the‐counter plant preparations as inhibitors of this urease and to determine whether they can prevent the increase in pH that normally occurs in bacterial cultures containing urea.
Methods and Results
Urease activity was measured colorimetrically by the formation of ammonium ions. The green tea and Uva‐Ursi preparations reduced urease activity in a soluble extract of S. saprophyticus by more than 75%. Two herbal mixtures were weakly inhibitory and reduced activity by about 25%, but the other products had little or no effect. The green tea and Uva‐Ursi extracts also inhibited urease activity in whole cells by more than 75%. One of the herbal products (WishGarden UTI) showed some inhibition of urease activity but the other (UTI Clear) did not. The green tea and Uva‐Ursi preparations prevented the increase in pH that normally occurs when S. saprophyticus is grown in an artificial urine medium, but this was due primarily to bacterial death. The WishGarden UTI preparation could partially delay the pH increase while allowing some cells to remain viable.
Conclusion
These results indicate that only a few of the commercially available over‐the‐counter plant preparations commonly used for the treatment of urinary tract infections (UTIs) can inhibit the urease activity from S. saprophyticus.
Significance and Impact of the Study
While over‐the‐counter plant preparations may be considered an alternative to traditional antibiotics for the treatment of UTIs, they should be used with caution and a product should be matched to the properties of the virulence factors of the bacterial pathogen involved.
Culture-independent studies have identified DNA of bacterial pathogens in the gallbladder under pathological conditions, yet reports on the isolation of corresponding live bacteria are rare. Thus, it ...is unclear which pathogens, or pathogen communities, can colonize the gallbladder and cause disease. Using light microscopy, scanning electron microscopy, culture techniques, phylogenetic analysis, urease assays and Western blotting, we investigated the presence of live bacterial communities in the gallbladder of a cholecystitis patient after cholecystectomy. 16S rRNA gene sequencing of isolated bacterial colonies revealed the presence of pathogens most closely resembling
nov. sp.,
and
. The latter colonies were confirmed as
by immunohistochemistry and biochemical methods.
cultured from the gallbladder exhibited both the same DNA fingerprinting and Western
gene sequence with ABC-type EPIYA (Glu-Pro-Ile-Tyr-Ala) phosphorylation motifs as isolates recovered from the gastric mucus of the same patient, suggesting that gastric
can also colonize other organs in the human body. Taken together, here we report, for the first time, the identification and characterization of a community consisting of live
;
, and
in the gallbladder of a patient with acute cholecystitis. Their potential infection routes and roles in pathogenesis are discussed.
The capacity of subinhibitory levels of antibiotics to modulate bacterial virulence in vitro has recently been brought to light, raising concerns over the appropriateness of low-dose therapies, ...including antibiotic prophylaxis for recurrent urinary tract infection management. However, the mechanisms involved and their relevance in influencing pathogenesis have not been investigated. We characterized the ability of antibiotics to modulate virulence in the uropathogens Staphylococcus saprophyticus and Escherichia coli. Several antibiotics were able to induce the expression of adhesins critical to urothelial colonization, resulting in increased biofilm formation, colonization of murine bladders and kidneys, and promotion of intracellular niche formation. Mice receiving subinhibitory ciprofloxacin treatment were also more susceptible to severe infections and frequent recurrences. A ciprofloxacin prophylaxis model revealed this strategy to be ineffective in reducing recurrences and worsened infection by creating larger intracellular reservoirs at higher frequencies. Our study indicates that certain agents used for antibiotic prophylaxis have the potential to complicate infections.
Antibiotics are the mainstay treatment for bacterial infections; however, evidence is emerging that argues these agents may have off-target effects if sublethal concentrations are present. Most studies have focused on changes occurring in vitro, leaving questions regarding the clinical relevance in vivo. We utilized a murine urinary tract infection model to explore the potential impact of low-dose antibiotics on pathogenesis. Using this model, we showed that subinhibitory antibiotics prime uropathogens for adherence and invasion of murine urothelial tissues. These changes in initial colonization promoted the establishment of chronic infection. Furthermore, treatment of chronically infected mice with subtherapeutic ciprofloxacin served to exacerbate infection. A part of these changes was thought to be due to suppression of mucosal immunity, as demonstrated through reductions in cytokine secretion and migration of leukocytes into the urinary tract. This work identifies novel risk factors associated with antibiotic therapy when dosing strategies fall below subtherapeutic levels.
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•Marine Staphylococcus saprophyticus SBPS15 produced a novel glycolipid biosurfactant.•Glycolipid structure was Mannose-Mannose-Oleic acid and named as Staphylosan.•Staphylosan ...revealed excellent surface tension reduction and CMC.•Staphylosan exhibited promising biofilm inhibition and dislodging activities.•Non-toxic nature of Staphylosan suggests its safe use for environmental applications.
Marine microbes have gained significant attention as potential biofactories for broad spectrum bioactive compounds. In the recent years, bioactive biosurfactants have warranted renewed interest from both environmental and clinical sectors as anti-biofilm agents due to their excellent properties of dispersing microbial biofilms. The present study explores a new glycolipid biosurfactant produced by a marine Staphylococcus saprophyticus exhibiting interesting biological activities. This glycolipid biosurfactant was purified and identified as Mannose-Mannose-Oleic acid (named as Staphylosan) based on the results of NMR, GC, GC–MS, MALDI-TOF-MS and tandem MS analysis. The surface tension and critical micelle concentration of purified Staphylosan was 30.9 mN m−1 and 24 mg L−1. Further, it showed promising biofilm inhibition and dislodging activities against a panel of profuse biofilm forming bacteria at both single and multi-species level which were isolated from boat hull biofilm environment such as Bacillus subtilis BHKH-7, Acinetobacter beijerinckii BHKH-11, Pseudomonas aeruginosa BHKH-19, Serratia liquefaciens BHKH-23, Marinobacter lipolyticus BHKH-31 and Micrococcus luteus BHKH-39. Moreover, it exhibited anionic charge and revealed non-toxicity towards brine shrimps, suggesting its environmental safety. This is a first report on Staphylosan, a multifunctional glycolipid surfactant from a marine Staphylococcus saprophyticus SBPS-15, exhibiting promising anti-biofilm activities and non-toxic in nature and thus finds possible potential use in many environmental applications especially under marine conditions.
This study assessed the antimicrobial resistance of airborne Staphylococcus spp. strains isolated from healthcare facilities in southern Poland. A total of 55 isolates, belonging to 10 ...coagulase-negative staphylococci (CoNS) species, isolated from 10 healthcare facilities (including hospitals and outpatient units) were included in the analysis. The most frequently identified species were Staphylococcus saprophyticus and Staphylococcus warneri, which belong to normal human skin flora, but can also be the cause of common and even severe nosocomial infections. Disk diffusion tests showed that the bacterial strains were most frequently resistant to erythromycin and tetracycline and only 18% of strains were susceptible to all tested antimicrobials. Polymerase chain reaction amplification of specific gene regions was used to determine the presence of the Macrolide-Lincosamide-Streptogramin resistance mechanisms in CoNS. The molecular analysis, conducted using specific primer pairs, identified the msrA1 gene, encoding active efflux pumps in bacterial cells, as the most frequent resistance gene. As many as seven antibiotic resistance genes were found in one isolate, whereas the most common number of resistance genes per isolate was five (n = 17). It may be concluded that drug resistance was widely spread among the tested strains, but the resulting antimicrobial resistance profile indicates that in the case of infection, the use of antibiotics from the basic antibiogram group will be effective in therapy. However, before administering treatment, determination of the specific antimicrobial resistance should be conducted, particularly in the case of hospitalized patients.
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