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This review article shows that coagulase-negative staphylococci (CoNS) are widely responsible for laryngological diseases. General characteristics of CoNS infections are shown in the introduction, and the pathogenicity in terms of virulence determinants, biofilm formation and genetic regulation mechanisms of these bacteria is presented in the first part of the paper to better display the virulence potential of staphylococci. The PubMed search keywords were as follows: CoNS and: nares infections, nasal polyps, rhinosinusitis, necrosing sinusitis, periprosthetic joint infection, pharyngitis, osteomyelitis of skull and neck bones, tonsillitis and recurrent tonsillitis. A list of laryngological infections and those related to skull and neck bones was presented with descriptions of the following diseases: rhinosinusitis, necrotizing sinusitis, nasal polyps, nares and nasal skin infections, periprosthetic joint infections, osteomyelitis, pharyngitis, and tonsillitis. Species identification and diagnostic problems challenging for diagnosticians are presented. Concluding remarks regarding the presence of CoNS in humans and their distribution, particularly under the effect of facilitating factors, are mentioned.

Coagulase-negative staphylococci, ubiquitous commensals of human skin, and mucous membranes represent important pathogens for immunocompromised patients and neonates. The increasing antibiotic resistance amongStaphylococcus epidermidisis an emerging problem worldwide. In particular, the linezolid-resistantS. epidermidis(LRSE) strains are observed in Europe since 2014. The aim of our study was to genetically characterize 11 LRSE isolates, recovered mostly from blood in the University Children’s Hospital in Krakow, Poland, between 2015 and 2017. For identification of the isolates at the species level, we used 16S rRNA sequencing and RFLP of thesaoCgene. Isolates were characterized phenotypically by determining their antimicrobial resistance patterns and using molecular methods such as PFGE, MLST, SCCmectyping, detection of theicaoperon, and analysis of antimicrobial resistance determinants. All isolates were multidrug-resistant, including resistance to methicillin, and exhibited so-called PhLOPSAphenotype. In PFGE, all isolates (excluding one from a catheter) represented identical patterns, were identified as ST2, and harbored theicaoperon, responsible for biofilm formation. Linezolid resistance was associated with acquisition of A157R mutation in the ribosomal protein L3 and the presence ofcfrgene. All isolates revealed new SCCmeccassette element composition. Recently, pediatric patients with serious staphylococcal infections are often treated with linezolid. The increasing linezolid resistance in bacterial strains becomes a real threat for patients, and monitoring such infections combined with surveillance and infection prevention programs is very important to decrease number of linezolid-resistant staphylococcal strains.

Linezolid is currently used to treat infections caused by multidrug-resistant Gram-positive cocci. Both linezolid-resistant S. aureus (LRSA) and coagulase-negative staphylococci (CoNS) strains have been collected worldwide. Two isolates carrying linezolid resistance genes were recovered from laryngological patients and characterized by determining their antimicrobial resistance patterns and using molecular methods such as spa typing, MLST, SCCmec typing, detection of virulence genes and ica operon expression, and analysis of antimicrobial resistance determinants. Both isolates were multidrug resistant, including resistance to methicillin. The S. aureus strain was identified as ST-398/t4474/SCCmec IVe, harboring adhesin, hemolysin genes, and the ica operon. The S. haemolyticus strain was identified as ST-42/mecA-positive and harbored hemolysin genes. Linezolid resistance in S. aureus strain was associated with the mutations in the ribosomal proteins L3 and L4, and in S. haemolyticus, resistance was associated with the presence of cfr gene. Moreover, S. aureus strain harbored optrA and poxtA genes. We identified the first case of staphylococci carrying linezolid resistance genes from patients with chronic sinusitis in Poland. Since both S. aureus and CoNS are the most common etiological factors in laryngological infections, monitoring of such infections combined with surveillance and infection prevention programs is important to decrease the number of linezolid-resistant staphylococcal strains.

Background: The use of antibiotics in dentistry is associated with the emergence and spread of antibiotic-resistant microorganisms, including commensal staphylococci. Methods: A total of 367 oral samples were collected, from which staphylococci were isolated and identified by using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF). The antibiotic susceptibility of the isolates was determined and molecular characteristics for methicillin-resistant staphylococci was performed. Results: A total of 103 coagulase-negative staphylococci (CoNS), among them S. warneri, S. haemolyticus, S. saprophyticus, S. pasteuri, S. epidermidis, S. hominis, S. xylosus, S. equorum, S. kloosii, S. succinus, S. cohnii, and S. simulans, were confirmed by MALDI-TOF. Resistance to most tested antibiotics was statistically higher in CoNS than in S. aureus isolates (P-value < 0.05). CoNS isolates showed high resistance to penicillin (S. saprophyticus 88.9%), erythromycin (S. haemolyticus 84.6%), fusidic acid (S. saprophyticus 77.8%), co-trimoxazole (S. epidermidis 71.4%), gentamicin (S. warneri 63.8%), and tetracycline (S. saprophyticus 55.6%). Multidrug resistance was largely observed, especially among S. haemolyticus and S. saprophyticus species. Methicillin-resistance in S. haemolyticus (38.5%), S. saprophyticus (22.2%) and S. aureus (13.5%) was associated with the presence of the mecA gene and SCCmec type IV or V. Conclusion: Coagulase-negative staphylococci, especially S. haemolyticus and S. saprophyticus, seem to be a reservoir of methicillin resistance and multidrug resistance in the oral cavity.

Growing antibiotic resistance of bacteria is a burning problem of human and veterinary medicine. Expansion and introduction of novel microbicidal therapeutics is highly desirable. However, antibiotic treatment disturbs the balance of physiological microbiota by changing its qualitative and/or quantitative composition, resulting in a number of adverse effects that include secondary infections. Although such dysbiosis may be reversed by the treatment with probiotics, a more attractive alternative is the use of antibiotics that target only pathogens, while sparing the commensals. Here, we describe lysostaphin LSp222, an enzyme produced naturally by Staphylococcus pseudintermedius 222. LSp222 is highly effective against S. aureus, including its multi-drug resistant strains. Importantly, the inhibitory concentration for S. epidermidis, the predominant commensal in healthy human skin, is at least two orders of magnitude higher compared to S. aureus. Such significant therapeutic window makes LSp222 a microbiota-friendly antibacterial agent with a potential application in the treatment of S. aureus-driven skin infections.

The oral cavity may comprise a significant reservoir for Staphylococcus aureus but the data on molecular epidemiology and clonal distribution of oral strains are really scarce. This study aimed to evaluate the clonal relatedness in S. aureus isolated from oral cavity and their relationship with carriage of virulence genes, and antimicrobial resistance profiles. A total of 139 oral S. aureus isolates were obtained from 2327 analysed oral samples of dental patients. Antimicrobial susceptibility testing was performed. Isolates were characterized using protein A gene (spa) typing, spa-CC clonal complexes, toxin genes and SCCmec typing for MRSA. High resistance rates for penicillin, tetracycline and gentamicin were detected, respectively 58.3%, 42.4%, and 35.2%. Twelve (8.6%) S. aureus isolates were identified as MRSA. All of MRSA isolates were mecA-positive and mecC-negative. SCCmec IV was the most common type (66.7%), which was typical for community-acquired MRSA (CA-MRSA). Overall, the enterotoxin gene cluster (egc) was the most frequent detected virulence factor (44.9%), both in MSSA and MRSA isolates. Presence of genes encoding for the enterotoxins (sea, seb, sec, seh, sek), exfoliative toxin A (eta), and toxic shock syndrome toxin-1 (tst) was also observed. Strains carrying lukS-PV/lukF-PV genes belonged to SCCmecV- spa type t437. The most prevalent spa types were t091, t015, t084, t002, t571, and t026 among all 57 identified. Spa types, including 3 new ones, grouped in 6 different spa-CC clonal complexes, with four major dominated; CC45, CC30, CC5, and CC15. This study demonstrated that both methicillin-susceptible and methicillin-resistant major European clones of S. aureus could be isolated from the oral cavity of dental patients, with the emergence of PVL-positive CA-MRSA strains. The oral cavity should be considered as a possible source of toxigenic egc-positive S. aureus strains, in terms of potential risk of cross-infection and dissemination to other body sites.

The spatial network structure of Dergall is based on substances nontoxic to humans and the environment which, when applied on solid surfaces, creates a coating that reduces bacterial cell adhesion. The bacteriostatic properties of siloxanes are based on a purely physical action mechanism which excludes development of drug-resistant microorganisms. The aims of the present study were to 1) evaluate a Dergall layer formed on the eggshell surface regarding the potential harmful effects on the chick embryo; 2) evaluate antimicrobial activity and estimate the prolongation time of Dergall's potential antimicrobial activity. Dergall at a concentration of 0.6% formed a layer on the eggshell surface. In vitro testing of the potential harmful effects of Dergall by means of a hen embryo test of the chorioallantoic membrane showed no irritation reaction at a concentration of 3% and lower. The hatchability of the groups sprayed with a Dergall water solution with a concentration of 0 to 5% was 89.1 to 93.8% for fertilized eggs (P > 0.05) but decreased to 63.7% (P

In veterinary medicine, Staphylococcus aureus is associated with a range of mild to severe infections. The high density of livestock in intensive farming systems increases the risk of disease spread and hampers its control and measures of prevention, making S. aureus one of the most important animal pathogens. Multiple-locus variable-number tandem repeat fingerprinting (MLVF) has been successfully applied to the characterization of livestock-associated meticillin-resistant Staphylococcus aureus (MRSA) ST398 but not to the characterization of a wide range of other animal isolates. The objective of the current study was to examine the effectiveness of MLVF for studying S. aureus strains isolated from households, farms and exotic animals in three regions of Poland. MLVF, random amplification of polymorphic DNA (RAPD), spa typing and diagnostic microarrays were compared to determine the most suitable combination of methods for veterinary purposes. MLVF generated results consistent with host and geographic origins, reflecting population structures with a high concordance to spa typing results. MLVF has been proven to be a rapid, highly discriminatory and cost-effective method suitable for molecular typing in veterinary settings.

Background Many members of Streptococcus and Enterococcus genera are clinically relevant opportunistic pathogens warranting accurate and rapid identification for targeted therapy. Currently, the developed method based on next generation sequencing (NGS) of the 16S–23S rRNA region proved to be a rapid, reliable and precise approach for species identification directly from polymicrobial and challenging clinical samples. The introduction of this new method to routine diagnostics is hindered by a lack of the reference sequences for the 16S–23S rRNA region for many bacterial species. The aim of this study was to develop a careful assignment for streptococcal and enterococcal species based on NGS of the 16S–23S rRNA region. Methods Thirty two strains recovered from clinical samples and 19 reference strains representing 42 streptococcal species and nine enterococcal species were subjected to bacterial identification by four Sanger-based sequencing methods targeting the genes encoding (i) 16S rRNA, (ii) sodA, (iii) tuf and (iv) rpoB; and NGS of the 16S–23S rRNA region. Results This study allowed obtainment and deposition of reference sequences of the 16S–23S rRNA region for 15 streptococcal and 3 enterococcal species followed by enrichment for 27 and 6 species, respectively, for which reference sequences were available in the databases. For Streptococcus, NGS of the 16S–23S rRNA region was as discriminative as Sanger sequencing of the tuf and rpoB genes allowing for an unambiguous identification of 93% of analyzed species. For Enterococcus, sodA, tuf and rpoB genes sequencing allowed for identification of all species, while the NGS-based method did not allow for identification of only one enterococcal species. For both genera, the sequence analysis of the 16S rRNA gene was endowed with a low identification potential and was inferior to that of other tested identification methods. Moreover, in case of phylogenetically related species the sequence analysis of only the intergenic spacer region was not sufficient enough to precisely identify Streptococcus strains at the species level. Conclusions Based on the developed reference dataset, clinically relevant streptococcal and enterococcal species can now be reliably identified by 16S–23S rRNA sequences in samples. This study will be useful for introduction of a novel diagnostic tool, NGS of the 16S–23S rRNA region, which undoubtedly is an improvement for reliable culture-independent species identification directly from polymicrobially constituted clinical samples.

This chapter presents characteristics of coagulases, including their biological activity and role in disease pathogenesis. There are two known staphylocoagulases: coagulase (Coa) and the von Willebrand factor-binding protein (vWpb); however, paralogues of the latter were also identified in animal-originated Staphylococcus aureus strains. Coagulases are proteins that nonenzymatically activate prothrombin, which, in turn, converts fibrinogen to fibrin, leading to blood clotting. Time of the clot generation varies for human and animals plasmas. This is due to differences in the activity of coagulase-prothrombin complexes, as well as to the existence of host-specific variants of vWbp, encoded on host-specific mobile genetic elements. Coagulases are staphylococcal key virulence factors contributing to the development of pseudocapsules that promote abscess formation and infection persistence as well as staphylococcal bacteraemia and endocarditis.

This chapter deals with animal models of staphylococcal infections, including mouse, rat, hamster, gerbil, bird, chicken embryo, rabbit, guinea pig, dog, nematode, insect, and fish models, as well as other rarely used animals. The aims of experimental infections by staphylococci are described, and a critical revision of Koch’s postulates presented. Problems related to laboratory safety arising from work with experimental microbial infections are enumerated, furthermore, and, finally, salient bioethical questions are faced.

Microbial ecology investigates the presence of microorganisms in the environment, mutual interactions, and their transfer from the environment to higher organisms. Many different environments are colonized by staphylococci, but the main reservoirs of these bacteria are humans and animals. Colonized niches and staphylococci affect each other in several ways, resulting in bio and geo conversions and causing rearrangements in bacterial genomes. Mutations, as acquirement of virulence and resistance determinants, can cause difficulties in diagnostics and therapy. Epidemiology investigates the occurrence and distribution of health-related states or events, including diseases, in different populations. Staphylococci are the most important human opportunistic pathogens; they colonize skin and mucous membranes of healthy individuals and are responsible for many diseases with diverse localizations and outcomes. Advances in molecular detection methods have enabled the identification of staphylococcal species responsible for infections in predisposed groups of patients based on phenotypic and genetic characteristics.

The process of adaptation of all bacterial species to the environment as well as the emergence of new pathogens involves the transfer of mobile genetic elements (MGEs). This phenomenon has a major impact on the evolution of Staphylococcus aureus, a commensal and facultative pathogen in humans and warm-blooded animals. Bacteriophage transduction is a source of various staphylococcal virulence factors that contribute to both strain diversity and host-specificity. Bacteriophages may also be associated with the staphylococcal pathogenicity islands SaPIs, that are another kind of MGE. The mobilization of SaPIs, followed by their excision from chromosomes, then replication and spread as they leave the host cell inside hijacked capsids, requires the presence of a helper phage. This modified transduction may be responsible for the spread of SaPI-encoded superantigenes among S. aureus strains, as well as other species. Furthermore, a subinhibitory concentration of β-lactam or fluorochinolone antibiotics promotes the spread of SaPIs and bacteriophages in pathogenic bacteria through SOS-mediated prophage induction. Tracking the dynamics of bacteria and phage co-evolution will provide insight into virulence mechanisms and improve therapy of staphylococcal infections.

The aim of current study was to examine clonal structure and genetic profile of invasive Staphylococcus aureus isolates recovered from infants and children treated at the Jagiellonian University Children's Hospital of Krakow, Poland. The 107 invasive S. aureus isolates, collected between February 2012 and August 2014, were analysed retrospectively. Antimicrobial susceptibility testing, spa typing and DNA microarray analysis were performed to determine clonal distribution, diversity and gene content in regard to patients characteristics. In total, 107 isolates were recovered from 88 patients with clinical symptoms of invasive bacterial infection. The final set of 92 non-duplicate samples included 38 MRSA isolates. Additionally, a set of 54 S. aureus isolates collected during epidemiological screening was genotyped and analysed. There were 72 healthcare-associated (HCA) and 20 community-onset (CO) infection events caused by 33 and 5 MRSA isolates, respectively. The majority of isolates were affiliated with the major European clonal complexes CC5 (t003, spa-CC 002), CC45 (spa-CC 015), CC7 or CC15 (t084, t091, spa-CC 084). Two epidemic clones (CC5-MRSA-II or CC45-MRSA-IV) dominated among MRSA isolates, while MSSA population contained 15 different CCs. The epidemiological screening isolates belonged to similar genetic lineages as those collected from invasive infection cases. The HCA infection events, spa types t003, t2642 or CC5 were significantly associated with infections occurring in neonates and children under 5 years of age. Moreover, carriage of several genetic markers, including erm(A), sea (N315), egc-cluster, chp was significantly higher in isolates obtained from children in this age group. The spa types t091 and t008 were underrepresented among patients aged 5 years or younger, whereas spa type t008, CC8 and presence of splE was associated with infection in children aged 10 years or older. The HCA-MRSA strains were most frequently found in children under 5 years, although the majority of invasive infections was associated with MSSA strains. Moreover, an association between age group of children from the study population and a specific strain genotype (spa type, clonal complex or genetic content) was observed among the patients.

The importance of nosocomial infections caused by coagulase-negative staphylococci is constantly growing. The threat primarily affects immunocompromised patients, the elderly and neonates, particularly after invasive surgery. The problem is fundamentally exacerbated by expanding antibacterial drug resistance. A case report is presented of an 86-year-old patient who underwent a ruptured abdominal aortic aneurysm surgery and developed septicaemia upon surgical wound infection. The causal agent was likely a carbapenem-resistant Klebsiella pneumoniae, however, daptomycin-resistant Staphylococcus pettenkoferi was identified in blood cultures in the absence of daptomycin treatment. To the authors' knowledge, the case study presented is the first published episode of daptomycin-resistant S. pettenkoferi strain.

Staphylococcus aureus infections are of major importance in human and veterinary medicine. Studies of the virulence of this bacterium are complicated by inconsistent results obtained in different animal models. We searched for an uncomplicated and inexpensive model suitable to study virulence of poultry strains of S. aureus using a genome-wide approach. We determined that a useful model would clearly differentiate strains of high and low virulence, and that this would generally correlate with the genetic relatedness among strains. To this end Gallus gallus (chicken) embryo and Caenorhabditis elegans (nematode) models were selected, and their response to challenge by a set of well-characterized Staphylococcus strains was evaluated. The chicken embryo model allowed to determine variation in virulence among strains of poultry and human origin. The survival of embryos ranged from 0% to almost 100% for the various strains. In contrast, variation in virulence of most strains in the nematode model was comparable, regardless of their origin or genotype, demonstrating limited usefulness of this model. Most importantly, a clear correlation was found between the virulence level in the embryo model and the genotype of the tested poultry strains. Our findings indicate the potential usefulness of embryo model for future identification of host-specific adaptations and virulence factors in S. aureus.

To determine the staphylococcal colonization pattern in healthy and diseased dogs, living in two particular environments, a number of microbiological samples were taken. Overall, twenty dogs, either healthy or with infected skin lesions, were examined. In each case bacterial swabs were collected from the nasal mucosa, ear, perineum, lumbo-sacralis triangle, and from the infection sites if such were present. A total number of 104 isolates representing different staphylococcal species were isolated and identified using routine biochemical methods applied in diagnostic laboratories. Among 17 isolated staphylococcal species, Staphylococcus intermedius was the most common species isolated from both healthy or diseased dogs living either in animal shelter or household environments. The pattern of Staphylococcus sp. colonization differs considerably for animals living in the two tested habitats. In particular, S. aureus MRSA and MSSA isolates were detected only in infected skin lesion samples from animals that dwelled in the animal shelter. As could be expected, S. intermedius was found to be a predominant causative agent in canine skin infections. In our study, we demonstrated that S. intermedius in its carrier-state, inhabits mainly the mucosal membrane of the nasal vestibule. It was also found in the samples taken from the skin, the lumbo-sacralis triangle and perineum, but was rarely isolated from the ears.

The influence of acetic and propionic acids on baker's yeast was investigated in order to expand our understanding of the effect of weak organic acid food preservatives on eukaryotic cells. Both acids decreased yeast survival in a concentration-dependent manner, but with different efficiencies. The acids inhibited the fluorescein efflux from yeast cells. The inhibition constant of fluorescein extrusion from cells treated with acetate was significantly lower in parental strain than in either PDR12 (ABC-transporter Pdr12p) or WAR1 (transcriptional factor of Pdr12p) defective mutants. The constants of inhibition by propionate were virtually the same in all strains used. Yeast exposure to acetate increased the level of oxidized proteins and the activity of antioxidant enzymes, while propionate did not change these parameters. This suggests that various mechanisms underlie the yeast toxicity by acetic and propionic acids. Our studies with mutant cells clearly indicated the involvement of Yap1p transcriptional regulator and de novo protein synthesis in superoxide dismutase up-regulation by acetate. The up-regulation of catalase was Yap1p independent. Yeast pre-incubation with low concentrations of H(2)O(2) caused cellular cross-protection against high concentrations of acetate. The results are discussed from the point of view that acetate induces a prooxidant effect in vivo, whereas propionate does not.

Staphylococcus pseudintermedius is a common commensal bacterium colonizing the skin and mucosal surfaces of household animals. However, it has recently emerged as a dangerous opportunistic pathogen, comparable to S. aureus for humans. The epidemiological situation is further complicated by the increasing number of methicillin-resistant S. pseudintermedius infections and evidence of gene transmission driving antibiotic resistance between staphylococci colonizing human and zoonotic hosts. In the present study, we describe a unique peptide, BacSp222, that possesses features characteristic of both bacteriocins and virulence factors. BacSp222 is secreted in high quantities by S. pseudintermedius strain 222 isolated from dog skin lesions. This linear, fifty-amino-acid highly cationic peptide is plasmid-encoded and does not exhibit significant sequence similarities to any other known peptides or proteins. BacSp222 kills gram-positive bacteria (at doses ranging from 0.1 to several micromol/l) but also demonstrates significant cytotoxic activities towards eukaryotic cells at slightly higher concentrations. Moreover, at nanomolar concentrations, the peptide also possesses modulatory properties, efficiently enhancing interferon gamma-induced nitric oxide release in murine macrophage-like cell lines. BacSp222 appears to be one of the first examples of multifunctional peptides that breaks the convention of splitting bacteriocins and virulence factors into two unrelated groups.

Objectives The presence of the arginine catabolic mobile element (ACME) in Staphylococcus aureus has been reported to enhance the colonization of the human host. The aim of this study was to determine the genetic organization of composite islands harbouring ACME. Methods Two ACME-positive S. aureus isolates obtained during two different surveys conducted in the Netherlands and Poland were characterized in this study. The isolates were analysed by spa typing, DNA microarrays and whole-genome sequencing. Results The two isolates harboured a truncated yet fully functional ACME type II with an identical nucleotide sequence, but differed in their adjacent mobile genetic elements. The first strain was a livestock-associated ST398-t011 MRSA, which had a staphylococcal cassette chromosome mec (SCCmec) composite island composed of SCCpls adjacent to orfX followed by ACME type II and SCCmec type IVa. The second ACME-positive isolate was an ST8-t008 MSSA. Its composite island showed an SCC-like element carrying the ccrC gene followed by ACME II. Conclusions This is the first report of an ACME in a livestock-associated MRSA ST398. It is also the first presentation of an ACME composite island structure in an MSSA isolate. Our findings indicate an extensive mosaicism of composite islands in S. aureus, which has implications for the transmissibility among humans and thus for public health.

Staphylococcus aureusstrains were isolated from mastitic milk of cows with infected mammary glands. The animals were living in 12 different farms near Lublin, in Central-Eastern Poland. A biochemical identification method based on enzymatic assay was performed, followed by haemolytic and proteolytic tests. PCR-RFLP targeted on thegapgene allowed the genetic identification of strains at the species level and verified phenotypic identification results. A molecular typing method using triplex PCR was performed to recognize the genetic similarity of the analyzed strains. DNA microarray hybridization (StaphyType, Alere Technologies) was used for detection of antibiotic resistance and virulence associated markers. The results obtained indicate high genetic similarity in strains isolated from the same sites. High genetic similarities were also detected between strains isolated from cows from different farms of the same region. A slightly lower similarity was noted however, in strains from various regions indicating that the strains are herd specific and that the cow’s infections caused byS. aureuswere of a clonal character. In 21 representative isolates selected for DNA-microarray testing, only fosfomycin (fosB) and penicillin resistance markers (blaZ, blaI, blaR) were detected. The presence of genes coding for haemolysins (lukF, lukS, hlgA, hla, hld, hlb), proteases (aur, sspA, sspB, sspP), enterotoxins (entA, entD, entG, entI, entJ, entM, entN, entO, entR, entU, egc-cluster), adhesins (icaA, icaC, icaD, bbp, clfA, clfB, fib, fnbA, map, vwb) or immune evasion proteins (scn, chp, sak) was common and, with exceptions, matched triplex PCR-defined clusters.

Genetic methods based on PCR-restriction fragment length polymorphism (RFLP) are widely used for microbial species determination. In this study, we present the application of saoC gene as an effective tool for species determination and within-species diversity analysis for Staphylococcus genus. The unique sequence diversity of saoC allows us to apply four restriction enzymes to obtain RFLP patterns, which appear highly distinctive even among closely related species as well as atypical isolates of environmental origin. Such patterns were successfully obtained for 26 species belonging to Staphylococcus genus. What is more, tracing polymorphisms detected by different restriction enzymes allowed for basic phylogeny analysis for Staphylococcus aureus, which is potentially applicable for other staphylococcal species.

A yeast isolate revealing unique enzymatic activities and substrate-dependent polymorphism was obtained from autochthonous microflora of soil heavily polluted with oily slurries. By means of standard yeast identification procedures the strain was identified as Trichosporon cutaneum. Further molecular PCR product analyses of ribosomal DNA confirmed the identity of the isolate with the genus Trichosporon. As it grew on methanol as a sole carbon source, the strain appeared to be methylotrophic. Furthermore, it was also able to utilize formaldehyde. A multi-substrate growth potential was shown with several other carbon sources: glucose, glycerol, ethanol as well as petroleum derivatives and phenol. Optimum growth temperature was determined at 25 degrees C, and strong inhibition of growth at 37 degrees C together with the original soil habitat indicated lack of pathogenicity in warm-blooded animals and humans. The unusually high tolerance to xenobiotics such as diesel oil (>30 g/l), methanol (50 g/l), phenol (2 g/l) and formaldehyde (7.5 g/l) proved that the isolate was an extremophilic organism. With high-density cultures, formaldehyde was totally removed at initial concentrations up to 7.5 g/l within 24 h, which is the highest biodegradation capability ever reported. Partial biodegradation of methanol (13 g/l) and diesel fuel (20 g/l) was also observed. Enzymatic studies revealed atypical methylotrophic pathway reactions, lacking alcohol oxidase, as compared with the conventional methylotroph Hansenula polymorpha. However, the activities of glutathione-dependent formaldehyde dehydrogenase, formaldehyde reductase, formate dehydrogenase and unspecific aldehyde dehydrogenase(s) were present. An additional glutathione-dependent aldehyde dehydrogenase activity was also detected. Metabolic and biochemical characteristics of the isolated yeast open up new possibilities for environmental biotechnology. Some potential applications in soil bioremediation and wastewater decontamination are discussed.

Multiple-locus variable-number tandem-repeat analysis (MLVA), a new PCR-based method of typing Staphylococcus aureus , was compared to pulsed-field gel electrophoresis (PFGE), spa typing, and multilocus sequence typing (MLST) on a group of 59 S. aureus (mostly methicillin-resistant) clinical isolates. The aim of the study was to establish possible criteria of clustering MLVA patterns and to check concordance levels between the results produced by MLVA and the three other typing methods. As in our earlier study, MLVA turned out to have discriminatory power similar to that of PFGE. Comparison of data obtained by the two approaches allowed us to propose a 70% or ca. 80% cutoff value of the similarity between two MLVA patterns, depending on a cutoff level applied to interpret the PFGE results, 75% or ca. 90%, respectively. The cutoff values corresponded to the difference of up to six or four bands, respectively, among maximum 14 bands in total produced by two isolates in the analysis. The MLVA clusters matched well those obtained by PFGE, and they were also consistent in general with clusters generated by spa typing and MLST, these latter methods characterized lower resolution. Our results suggest that MLVA may be reliable in shorter-term S. aureus epidemiological studies, including analyses of outbreaks and hospital-to-hospital strain transmission events. Well-known advantages of typing methods based on PCR (low cost, short time, and easiness of performance) make MLVA a method that may be useful in a variety of laboratories, including those performing routine microbiological analyses within medical centers.

Involvement of phagocyte NADPH oxidase in host defense response is well established. In contrast, little is known about the functional role of NADPH oxidase in platelets. In this study, we analyzed involvement of platelet NADPH oxidase in aggregation of human platelets and in amplification of production of reactive oxygen species (ROS) by activated human neutrophils. Apocynin, a known NADPH oxidase inhibitor, as well as superoxide dismutase mimetic Mn(III)tetrakis(1-methyl-1-pyridyl)porphyrin, inhibited ROS generation by collagen-activated platelets, collagen-induced aggregation of platelets, as well as collagen-induced release of thromboxane B2. These data suggest the key role of intracellular ROS derived from NADPH oxidase in the control of thromboxane A2 (TXA2) production in platelets stimulated by collagen. Apocynin also inhibited thrombin-induced ROS production and thrombin-induced platelet aggregation. Activation of neutrophils with latex resulted in an outburst of ROS that was inhibited by apocynin. ROS production by latex-stimulated platelets was modest and also inhibited by apocynin. However, when a mixture of platelets and neutrophils was stimulated with latex, ROS production was three to six times higher in comparison with activation of neutrophils alone. Platelet-dependent augmentation of neutrophil ROS production was abrogated by TXA2 synthase inhibitor (furegrelate, 1 microM) or by aspirin (300 microM). In summary, NADPH oxidase in platelets seems to play a major role as an intracellular signaling mechanism in the activation of platelets. However, in host defense response involving neutrophils and platelets, platelets enhance ROS production by neutrophils and possibly their cytotoxic potential via the release of TXA2, which in turn in platelets is not affected by the extracellular release of free radicals.

Summary Adult Dendrobaena veneta (Annelida; Oligochaete; Lumbricidae), were kept for 2–4 weeks at either 22 °C or 10 °C in control (C) heavy metal-free commercial soil, or in relatively unpolluted Krakow (K) urban soil, or in heavily polluted (Zn>Pb>Cd) Bukowno (B) industrial soil. At the end of exposures, the numbers of coelomocytes, brown bodies, and bacterial content was measured in coelomic fluid, while heavy metal accumulation was recorded in the animal tissues. The most drastic changes, with high mortality of animals (30%), were recorded in D. veneta kept for 4 weeks at 22 °C in heavily polluted B soil samples; the number of free coelomocytes in the surviving worms in this treatment group was decreased, whilst the numbers of brown bodies and of bacteria (both free in coelomic fluid and entrapped in the brown bodies) were significantly increased. These changes were absent in earthworms exposed to B soil at 10 °C, as well as at both temperatures in relatively uncontaminated K soil.

Through a CAMP test, we first observed a Staphylococcus delphini strain (ATCC 49172) to release beta-haemolysin. Production of the latter in this coagulase-positive species of the 'Staphylococcus intermedius Group', in fact, has been labeled to be undetermined, thus far. Of course, a wider number of strains have to be investigated in order to define whether this property is constitutive (like in Staphylococcus (pseud)intermedius), or strain-dependent (like in Staphylococcus aureus), and which clinical impact it has; nevertheless, we can state that S. delphini ATCC 49172 indeed produces this toxin.

Staphylococcal serine proteinase (SSP) can influence various functions of human polymorphonuclear leukocytes (PMNL) including chemotaxis and phagocytosis. Since the rise in intracellular free calcium concentration is an important step in signal transduction leading to phagocyte activation, we tested the ability of SSP to increase the intracellular free calcium concentration in human PMNL using the fluorescent calcium indicator Fura-2AM. PMNL isolated from healthy donors responded to SSP in the concentration range of 10 to 100 micrograms/ml. The highest Ca2+ rise (104 +/- 47 nM) was observed for 10 micrograms/ml SSP. It was mainly dependent (81 +/- 11%) on extracellular calcium influx, however, SSP mobilized 68 +/- 7% of Ca2+ from intracellular calcium stores. Boiling of SSP or preincubation with phenylmethylsulphonylfluoride (an serine proteinase inhibitor) did not change its ability to increase intracellular free calcium concentration in PMNL. It suggests that active center of SSP is not responsible for Ca2+ mobilization. Finally, PMNL responded to each of three consecutive stimulations with SSP independently of the presence of high or low extracellular Ca2+ concentration. This may be an additional mechanism responsible for activation of human PMNL and degradation of alveolar walls during the staphylococcal infection in the lower airways.

The contribution of carbohydrates to non-enzymatic processes such as glycation/autoxidation has been extensively investigated over the last decades. This may be attributed to either beneficial or detrimental effects of reducing carbohydrates, and most studies in the field of glycoxidation are focused on glucose. Non-enzymatic reactions of fructose have not been as thoroughly investigated as those of glucose. To compare glucose and fructose involvement in the generation of glycoxidation products under experimental conditions close to the physiological situation, we used intact Saccharomyces cerevisiae cells as in vivo model and cell-free extracts prepared from whole yeast cells as in vitro model. Both intact cells and cell-free extracts were incubated with glucose or fructose. It was shown that: (i) in vitro fructose was more reactive than glucose and produced higher level of autoxidation and glycation products; (ii) no substantive differences were observed for the effect of glucose and fructose on the intracellular level of glycoxidation products, when intact yeast cells were exposed to the high concentration of hexoses; (iii) the activity of defensive enzymes (superoxide dismutase, catalase, glyoxalases, and glutathione reductase) was increased in both glucose- and fructose-stressed yeasts, indicating the development of oxidative/carbonyl stress; (iv) glucose-6-phosphate dehydrogenase activity significantly dropped in yeast exposed to both hexoses, demonstrating its high sensitivity to reactive oxygen and carbonyl species; and (v) fructose more markedly activated glyoxalases than glucose. Involvement of glucose and fructose in the glycoxidation reactions as well as potential role of antioxidant and antiglycation enzymes in yeast protection against glycoxidation are discussed.

Propionibacterium acnes is dominating group of resident bacteria in skin biocenosis. These bacteria participate in autosterilisation of skin with the process of decomposition of triglycerides into free fatty acids and by keeping the pH of skin on the level 5.5. When the process goes out of control the excess of fatty acids in sebaceous glands leads to necrosis and inflammation. Apart of the presence on the skin P acnes also are present in mucous membranes of intestinal tract, eyes, internal ears channels, and in upper respiratory tracts. Traditionally they are regarded as anaerobes, but they tolerate oxygen atmosphere and are resistant to phagocytosis, surviving even in macrophages. These bacteria produce a number of enzymes and proinflammatory factors activating monocytes, stimulating mitogenic activity of lymphocytes T. According to common opinion they are responsible for disease acne vulgaris, but there are also researchers claiming their low pathogenicity. The list of the P acnes related diseases is not short, some of these diseases may be facilitated by predisposing factors as surgery interventions, diagnostic, or cosmetic procedures. The aim of the study was to compare standard biochemical analysis of P acnes strains to genotypic typing basing on the results from MP-PCR analyses. Relations of hemolysis activity to biochemical types or genetic types were also analysed.The analysis of 66 P acnes strains isolated from skin lesions of patients with acne vulgaris was performed. A collection of the strains was analysed biochemically according to Pulverer, Sourek and Hoffler method modified by Kasprowicz, and typed genetically by MP-PCR method. Relations of biochemical and genetic types to beta-hemolysis of strains were studied.Dominating biochemical type was type number I grouping 79% of all isolates, and dominant genotype was A which was detected in 75% of all collected strains. Beta-hemolysis was a feature present in 34% of strains, more frequently in type I (40%) than in type II (12%). beta-hemolysis was present only in A-genotype strains, but A-genotype by itself does not determine that reaction: 53% of A-genotype strains does not exhibit beta-hemolysis. All type I strains represent A-genotype. Type II was genotypicaly differentiated: all genotypes A, A', B, and C were present.The results obtained show genotypic heterogenity of P acnes strains and relations to biochemical types. Hemolysis was detected independently to biotype or genotype representation. The results confirm biochemical and genetic heterogenities of P acnes, but the observations also indicate necessity of further microbiological-molecular investigation of that bacteria group using other molecular techniques to the study.

Proteases of Staphylococcus aureus have long been considered to function as important virulence factors, although direct evidence of the role of particular enzymes remains incomplete and elusive. Here, we sought to provide a collective view of the prevalence of extracellular protease genes in genomes of commensal and pathogenic strains of S. aureus and their expression in the course of human and mouse infection. Data on V8 protease, staphopains A and B, aureolysin, and the recently described and poorly characterized group of six Spl proteases are provided. A phylogenetically diverse collection of 167 clinical isolates was analyzed, resulting in the comprehensive genetic survey of the prevalence of protease-encoding genes. No correlation between identified gene patterns with specific infections was established. Humoral response against the proteases of interest was examined in the sera derived from human patients and from a model mouse infection. The analysis suggests that at least some, if not all, tested proteases are expressed and secreted during the course of infection. Overall, the results presented in this study support the hypothesis that the secretory proteases as a group may contribute to the virulence of S. aureus.

Fructose is commonly used as an industrial sweetener and has been excessively consumed in human diets in the last decades. High fructose intake is causative in the development of metabolic disorders, but the mechanisms underlying fructose-induced disturbances are under debate. Fructose compared to glucose has been found to be a more potent initiator of the glycation reaction. Therefore, we supposed that glucose and fructose might have different vital effects. Here we compare the effects of glucose and fructose on yeast cell viability and markers of carbonyl/oxidative stress. Analysis of the parameters in cells growing on glucose and fructose clearly reveals that yeast growing on fructose has higher levels of carbonyl groups in proteins, α-dicarbonyl compounds and reactive oxygen species. This may explain the observation that fructose-supplemented growth as compared with growth on glucose resulted in more pronounced age-related decline in yeast reproductive ability and higher cell mortality. The results are discussed from the point of view that fructose rather than glucose is more extensively involved in glycation and ROS generation in vivo, yeast aging and development of carbonyl/oxidative stress. It should be noted that carbohydrate restriction used in this study does not reveal a significant difference between markers of aging and carbonyl/oxidative stress in yeasts cultivated on glucose and fructose.

Staphylococcus aureus is a prominent human pathogen and a leading cause of community- and hospital-acquired bacterial infections worldwide. Herein, we describe the identification and characterization of the S. aureus 67.6-kDa hypothetical protein, named for the s urface factor promoting resistance to o xidative k illing (SOK) in this study. Sequence analysis showed that the SOK gene is conserved in all sequenced S. aureus strains and homologous to the myosin cross-reactive antigen of Streptococcus pyogenes. Immunoblotting and immunofluorescence analysis showed that SOK was copurified with membrane fractions and was exposed on the surface of S. aureus Newman and RN4220. Comparative analysis of wild-type S. aureus and an isogenic deletion strain indicated that SOK contributes to both resistance to killing by human neutrophils and to oxidative stress. In addition, the S. aureus sok deletion strain showed dramatically reduced aortic valve vegetation and bacterial cell number in a rabbit endocarditis model. These results, plus the suspected role of the streptococcal homologue in certain diseases such as acute rheumatic fever, suggest that SOK plays an important role in cardiovascular and other staphylococcal infections.

The study was designed to demonstrate the relationship between the activity of human normal monocytes and blood platelets, to determine the metabolic activity of normal monocytes and monocytes cooperating with blood platelets in respect of their generation of reactive oxygen species (ROS) and to study the response of cooperating cells to nicotinamide (NA), 1-methylnicotinamide (MNA+) and 1-methyl-N'-hydroxymethylnicotinamide (MNAF+). The ability of those potential antiinflammatory compounds to inhibit oxygen respiratory burst was also assessed. Measurements were carried out by luminol chemiluminometry. The results of the measurements were compared to the data acquired for aspirin (ASA). The results obtained showed that MNAF inhibited oxygen burst in monocytes cooperating with platelets, whereas the two other compounds, NA and MNA, did not cause inhibition of oxygen burst in vitro at a statistically significant level.

This article presents human diseases where the main etiological factor is hypereosinophily: eosinophilic cystitis - EC, eosinophilic gastrointestinal disorders - EGID, which includes eosinophilic esophagitis - EE, and eosinophilic gastritis - EG, and finally nasal polyps - NP. A particular stress is put on the absence of correlations between circular hypereosinophily and presence of the described diseases.

Neutrophils and platelets circulate in blood system and play important physiological roles as part of immunological system. Neutrophils are the first line of host defense against various intruders, and platelets are satellite cells cooperating with other components of defense system. Recent studies report about the cooperation among these types of cells. We analyzed the effect of platelets on oxygen burst in neutrophils triggered by Staphylococcus aureus and Escherichia coli bacteria in vitro. The effect of platelets on oxygen burst in neutrophils was measured by luminol enhanced chemiluminescence. Opsonized and non-opsonized bacteria were used as activators. Activation of neutrophils with live non-opsonized and opsonized bacteria in the presence of platelets increased the oxygen burst as compared to the same system without platelets. The gram-positive bacteria (Staphylococcus aureus) were causing higher activation than gram-negative bacteria (Escherichia coli). This work demonstrate that platelets potentate the response of neutrophils augmenting their respiratory burst in vitro when triggered by bacteria.

Typing of Staphylococcus aureus isolates is a necessary procedure for monitoring the transmission of S. aureus among carriers and in epidemiology. Evaluation of the range of relationship among isolates rely on epidemiological markers and is possible because of the clonal character of S. aureus species. Effective typing shows the scheme of transmission of infection in a selected area, enables identifying the reservoir of the microorganism, and may enhance effective eradication. A set of typing methods for use in analyses of epidemiological correlations and the identification of S. aureus isolates is presented. The following methods of typing are described: biotyping, serotyping, antibiogram, protein electrophoresis, cell protein profiles (proteom), immunoblotting, multilocus enzyme electrophoresis (MLEE), zymotyping, and standard species identification of S. aureus in the diagnostic laboratory. Phenotyping methods for S. aureus isolates used in the past and today in epidemiological investigations and in analyses of correlations among S. aureus isolates are presented in this review. The presented methods use morphological characteristics, physiological properties, and chemical structures of the bacteria as criteria for typing. The precision of these standard methods is not always satisfactory as S. aureus strains with atypical biochemical characters have evolved recently. Therefore it is essential to introduce additional typing procedures using molecular biology methods without neglecting phenotypic methods.

Fluorescein efflux from S. cerevisiae cells was measured to study the peculiarities of fluorescein transport system, which is important for yeast resistance to certain drugs and weak organic acid preservatives. Glucose-independent and glucose-stimulated fluorescein effluxes were characterized using iodoacetate, cyanide and orthovanadate, inhibitors of glycolysis, electron transport chain, and ATPases, respectively. It is supposed that in glucose-free medium fluorescein extrusion is ATP-dependent and the energy for this efflux is mainly provided by respiration. In glucose-containing medium, glycolysis plays a critical role for extrusion of fluorescein. The results indicate that acetic acid inhibits the fluorescein efflux from yeast cells. The inhibition constant of glucose-stimulated fluorescein efflux is significantly lower in parental strain than in two mutants defective in PDR12 (ABC-transporter Pdr12p) or WAR1 (transcription factor of Pdr12p). It can be suggested that the membrane protein Pdr12 is involved in fluorescein extrusion from the yeast cells, but component(s) other than Pdr12p is (are) also important.

The interactions between polymorphonuclear cells (PMN), Staphylococcus saprophyticus cells and rabbit antibodies against Staphylococcus aureus V8 serine proteinase or normal rabbit serum proteins were investigated. The effect of opsonization on phagocytosis due to human peripheral polymorphonuclear cells was measured. The results were as follows: phagocytosis index values were relatively increased after the incubation of PMN cells with anti-serine proteinase gamma-globulin serum fraction, anti-serine proteinase IgG, non-immunized rabbit serum or with complement.

In this study, we compared the potentials of (i) a multiplex PCR-based multilocus variable-number tandem repeat (VNTR) assay; (ii) a triplex PCR coamplifying fragments of spa , coa , and the hypervariable region adjacent to the mecA gene; (iii) restriction profile analysis of the STAR repetitive element; (iv) randomly amplified polymorphic DNA analysis; (v) inter-IS 256 PCR; and (vi) rep-MP3 PCR. Multilocus VNTR typing and triplex PCR ( coa , spa , and hypervariable region) approaches showed excellent reproducibility and high discriminatory power; however, only multilocus VNTR typing could distinguish all pulsed-field gel electrophoresis and spa types. Multilocus VNTR typing appears to be the most useful PCR-based method for the rapid genotyping of Staphylococcus aureus strains.