Antimicrobial susceptibilities of Propionibacterium acnes isolated from patients with acne vulgaris

Antibiotic susceptibilities of Propionibacterium acnes in Japan were determined. Erythromycin‐resistance was found in 10.4% (5/48) of the strains, and four of these were cross‐resistance to clindamycin. Although the erythromycin ribosome methylase gene erm(X) was looked for, no strain carrying erm(X) was found. Sequencing analysis revealed that all of the erythromycin‐resistant strains had a mutation in the peptidyl transferase region of the 23S rRNA gene: G2057A, A2058G, or A2059G. Consequently, our results show that P. acnes resistance to macrolides is caused by a mutation in the 23S rRNA gene, and has been increasing in Japan.     

Staphylococcus aureus isolated from Kawasaki disease patients hyper-releases extracellular protein A.

S. aureus isolates from patients with Kawasaki disease (KD) release high levels of extracellular protein A (SpA), as compared to S. aureus in other diseases. The molecular weight of this released protein A is about 70 kDa. Extracellular KD SpA purified by affinity chromatography possessed the same amino acid sequence at the NH2-terminal IgG binding region and the same antigenic specificity as recombinant and cell-wall-bound SpA preparations. The size of DNA fragments containing the spa gene from S. aureus KD strains was 160-165 kb. All of these DNA fragments contained the igb portion encoding the IgG-binding region of KD SpA. Significantly higher molecular size of the SpA molecules hyper-released in the stationary-phase culture and the lack of production of other exo-proteins allow us to speculate that S. aureus isolated from patients with KD have mutations occurring in the agr locus.     

Genetic homogeneity/heterogeneity of Propionibacterium acnes isolated from patients during cardiothoracic reoperation

Following cardiothoracic surgery, deep sternal wound infection (SWI) remains one of the most severe complications. Recently, Propionibacterium acnes has been suspected as an etiological agent of deep SWI. However, this bacterium constitutes part of the resident micro-flora of the human skin. Consequently, findings of P. acnes in invasive samples are difficult to value. The aims of this study were to develop and optimize a pulsed-field gel electrophoresis (PFGE) protocol for P. acnes, in order to investigate the genetic homogeneity/heterogeneity of P. acnes isolates from multiple tissue samples (predominantly biopsies), collected at different locations, from 12 patients during cardiothoracic reoperation. There were 24 distinguishable PFGE fingerprints identified among the P. acnes isolates (n=54). Five (42%) of the patients carried only isolates that were interpreted as presumably clonally related. From the remaining seven patients, two or three different P. acnes clones were cultured, however, from six of them, the clones were identified in multiple samples. P. acnes may be a relatively frequent etiological agent of postoperative cardiothoracic infections. Existence of several clonally related P. acnes isolates derived from multiple samples from patients suffering from deep SWI after cardiothoracic surgery has not previously been shown.     

Biotyping of Propionibacterium acnes isolated from normal human facial skin

Biochemical and serological characteristics of 128 strains of Propionibacterium acnes isolated from the facial skin of healthy Japanese volunteers were compared with the three standard strains of the American Type Culture Collection, ATCC 6919, 11827, and 11828. Accordingly, the isolated strains of P. acnes were classified into five biotypes (B1 to B5) on the basis of fermentation tests of ribose, erythritol, and sorbitol. Two serotypes were distinguished by the agglutination test. P. acnes belonging to serotype I had galactose as a cell wall sugar, whereas those of serotype II lacked galactose. The strains of serotype I were distributed among all five biotypes (B1 to B5); however, those of serotype II consisted only of one biotype (B2). A term "sero-biotype" was introduced to differentiate and carefully classify the isolates. The predominant sero-biotypes differed with the individual and region of the facial skin. In general, strains of sero-biotype IB1, IB3, IB4, and IIB2 were more frequently isolated than those of sero-biotype IB2 and IB5. Thus, for routine assay work, serotyping of P. acnes as based on erythritol and sorbitol fermentation is both practical and applicable.     

Comparative studies of porphyrin production in Propionibacterium acnes and Propionibacterium granulosum.

Porphyrin production by Propionibacterium acnes and that by Propionibacterium granulosum were compared. Porphyrin synthesized by both organisms was identified as coproporphyrin III on the bases of absorption and fluorescence spectra and behavior on paper chromatography and thin-layer chromatography. Quantitative, rather than qualitative, differences in production were found between these organisms. In general, P. granulosum produced significantly greater amounts (P less than 0.001) of porphyrin than did P. acnes. delta-Aminolevulinic acid synthetase appeared to be the rate-limiting enzyme of the heme biosynthetic pathway in both organisms. The increased porphyrin production in P. granulosum is apparently associated with increased delta-aminolevulinic acid synthetase activity.     

Properties and characteristics of a bacteriocin-like substance produced by Propionibacterium acnes isolated from dental plaque

A cell-associated bacteriocinlike substance with an approximate molecular weight of 78,000 was isolated from an oral isolate of Propionibacterium acnes. The substance was bacteriostatic and was active against both gram-positive and gram-negative anaerobes. Lysozyme inhibited the activity of the bacteriocinlike substance at low ionic strength.     

Purification and characterisation of lipoglycan macroamphiphiles from Propionibacterium acnes

Lipidated macroamphiphiles such as the lipoteichoic acids and mycobacterial lipoarabinomannans are cell envelope components of Gram-positive bacteria that have been extensively associated with the pathogenesis of disease. In order to study such associations, purification of these macroamphiphiles is essential for resolving their structures and diverse biological effects. We describe herein a method for purification of lipoglycan components from Propionibacterium acnes. This method uses the existing phenol-water extraction, followed by hydrophobic interaction chromatography and an additional purification step that utilises preparative electrophoresis for the separation of two lipoglycan components. Analysis of these lipoglycans revealed evidence for a lipid anchor based on fatty acids whilst the polysaccharide moiety contained significant amounts of mannose, glucose and galactose, together with an amino sugar suspected of being a diaminohexuronic acid. These latter components have been previously identified as components of the P. acnes cell wall polysaccharide. Consequently, it is proposed that there may be a relationship between the structures of these distinctive cell envelope polymers.     

Isolation of Propionibacterium acnes from central nervous system infections

Propionibacterium acnes is a common skin colonizer and its involvement in central nervous system (CNS) infections may be related with previous neurosurgical procedures. P. acnes was isolated in pure or mixed cultures from ten patients with CNS infections during a 5-year period. The clinical presentation, treatment and outcome were retrospectively reviewed. Nine out of 11 patients had CNS infections after a neurosurgical procedure. The clinical presentation was: brain abscess (five patients), subdural or epidural empyema (four patients) and shunt meningitis (one patient). Three patients had also secondary meningitis. All patients received antibiotic therapy and all abscesses and empyemas were drained. The patient with shunt meningitis cured without catheter removal. Only one patient with a brain abscess by P. acnes died, but several months thereafter and as a consequence of a Gram-negative superinfection. P. acnes is a pathogen for the CNS and infections must be surgically managed under adequate antibiotic treatment.     

Rapid identification using pyrolysis mass spectrometry and artificial neural networks of Propionibacterium acnes isolated from dogs

Curie-point pyrolysis mass spectra were obtained from reference Propionibacterium strains and canine isolates. Artificial neural networks (ANNs) were trained by supervised learning (with the back-propagation algorithm) to recognize these strains from their pyrolysis mass spectra; all the strains isolated from dogs were identified as human wild type P. acnes. This is an important nosological discovery, and demonstrates that the combination of pyrolysis mass spectrometry and ANNs provides an objective, rapid and accurate identification technique. Bacteria isolated from different biopsy specimens from the same dog were found to be separate strains of P. acnes , demonstrating a within-animal variation in microflora. The classification of the canine isolates by Kohonen artificial neural networks (KANNs) was compared with the classical multivariate techniques of canonical variates analysis and hierarchical cluster analysis, and found to give similar results. This is the first demonstration, within microbiology, of KANNs as an unsupervised clustering technique which has the potential to group pyrolysis mass spectra both automatically and relatively objectively.     

Genetic basis of resistance in Propionibacterium acnes strains isolated from diverse types of infection in different European countries

The purpose of the study was to characterize the resistance mechanism of 36 clindamycin (CL) and erythromycin (EM) resistant Propionibacterium acnes strains and 27 tetracycline (TET) resistant P. acnes isolates, collected from nine European countries, both from acne patients and from patients with different infections. PCR and sequencing of the genes encoding domain V of 23S rRNA for CL and EM resistant strains and 16S rRNA for TET resistant strains were performed. Pulsed-field gel electrophoresis was used as a typing method to establish the relationship between resistance genotypes and pulsed-field types. Several unique resistant genotypes were found to be distributed throughout Europe. P. acnes CL and EM resistant strains carrying one of the mutations within the 23S rRNA were predominantly isolated from Swedish acne patients (64%) compared to other infections (43%), OR=2.33 [CI=1.16-4.69]. Of 36 P. acnes isolates tested, none was found to carry the erm(X) resistance gene. Forty-four percent of TET resistant strains were found to carry a G-C transition in the 16S rRNA of the small ribosomal subunit and all these strains were isolated from Swedish acne patients. MIC of TET among all strains carrying this G-C mutation (n=12) was 32 mg/L and the MIC range for the strains where no mutation was detected ranged from 2 to 8 mg/L. The MIC values of TET were unaffected by the presence of reserpine, a well-known inhibitor of efflux pumps. Those TET resistant strains harbouring the mutation at 16S rRNA were clustered in one pulsotype. For TET resistant strains where no mutation was found, greater variability was noticed. No correlation was noticed between different resistance genotypes of CL and EM resistant strains and pulsed-field types.     

Characteristics of the Propionibacterium strains isolated from acne patients

Propionibacterium acnes is a component of physiological flora of human skin. It colonizes the outlets of sebaceous glands and participates in the pathogenesis of inflammatory acne. Acne vulgaris is a common skin disease. It is found in more or less exacerbated form in approximately 85% of adolescent population. The main purpose of the research was to confirm the hypothesis of Propionibacterium bacteria participation in the aetiopathogenesis of acne vulgaris. The researches have proved the presence of Propionibacterium acnes on the surface of the skin both of people with acne-related changes and these with whom such changes were not found. Statistically significant differences were found in the number of P. acnes bacteria per 1 square centimeter of healthy and disease-affected skin as well as in the diversity of biochemical types. The highest number of P. acnes bacteria have been found in fresh changes with visible symptoms of inflammation. In order to confirm the hypothesis of the participation of Propionibacterium bacteria in the aetiopathogenesis of acne, a detailed phenotypical analysis of isolated P. acnes strains have been conducted. Type, biotype, resistance pattern, proteolytic and lipolytic properties have been determined.     

In vitro activity of kaempferol isolated from the Impatiens balsamina alone and in combination with erythromycin or clindamycin against Propionibacterium acnes

The in vitro antibacterial activity against antibiotic-resistant Propionibacterium acnes of kaempferol isolated from the Impatiens balsamina alone and in combination with erythromycin or clindamycin antibiotics was investigated. The antibiotic combination effect against antibiotic-resistant P. acnes was studied by checkerboard test. Kaempferol and quercetin demonstrated antibacterial activities against P. acnes. Minimum inhibitory concentrations (MICs) for both compounds were < or =32 ug/ml and < or =64 ug/ml for clindamycin-sensitive and-resistant P. acnes, respectively. The four combination formulations (kaempferol and either erythromycin or clindamycin; quercetin and either erythromycin or clindamycin) exhibited a synergic inhibition of P. acnes growth. The combination of kaempferol with quercetin showed an indifferent effect. The combination of clindamycin with kaempferol or quercetin showed a greater synergic effect than that of erythromycin with kaempferol or quercetin. Thus, these combinations demonstrated the potential to treat acne.     

Propionibacterium acnes in the etiology of endocarditis]

Propionibacterium acnes is the gram positive anaerobic bacteria belongs to the normal skin and oral microbial flora. The participation of this microorganism in the infective endocarditis is still controversial. The aim of the study was to perform the diagnostic and therapeutic difficulties in 5 patients with infective endocarditis caused by Propionibacterium acnes. In 3 out of 5 patients the infective endocarditis developed after prosthesis valve replacement, in 2 others on the native valves. The inserted prostheses were mechanical ones, propionibacterium acnes was identified as causative organisms in all of the causes (two positive blood and/or valve culture). The bacterial strains were sensitive to the antibiotics as: penicillins, cephalosporins, clindamycin, and vancomycin, however cephalosporins used at the beginning of the treatment in 3 patients and clindamycin in 1 patient had limited clinical efficacy. Later treatment with timentin, augmentin and tienamycin was successful in 3 patients; one patient was cured with vancomycin. One patient died because of septic, embolic complication in early stage of illness. We conclude the effectiveness of penicillins in combination with clavulanic acid and tienamycin in therapy of infective endocarditis due to Propionibacterium acnes. The treatment should be lasted during 4-6 weeks.     

Antibiotic-resistant Propionibacterium acnes on the skin of patients with moderate to severe acne in Stockholm

The objective was to study the prevalence and antibiotic susceptibility patterns of Propionibacterium acnes strains isolated from patients with moderate to severe acne in Stockholm, Sweden and to determine the diversity of pulsed-field gel electrophoresis types among resistant P. acnes strains. One hundred antibiotic-treated patients and 30 non-antibiotic-treated patients with moderate to severe acne participated in the investigation. Facial, neck and trunk skin samples were taken with the agar gel technique. The susceptibility of P. acnes strains to tetracycline, erythromycin, clindamycin and trimethoprim-sulfamethoxazole was determined by the agar dilution method. The genomic profiles of the resistant strains were determined by pulsed-field gel electrophoresis. In the group of patients treated with antibiotics, resistant P. acnes strains were recovered in 37%, while in the non-antibiotic group of patients the incidence of resistant strains was 13%. Thus antibiotic-resistant P. acnes strains were significantly more often isolated from antibiotic-treated patients with moderate to severe acne than from non-antibiotic-treated patients (odds ratio, 3.8; P=0.01). There was a genetic diversity among the P. acnes strains. Forty-four different patterns of SpeI DNA digests were detected and two predominant clones were found. P. acnes strains exhibited different antibiotic susceptibility patterns and identical genotypes or vice versa. A person can be colonized with different strains with varying degrees of antibiotic resistance. The risk of increased resistance of P. acnes must be considered when treating acne patients with antibiotics, and especially long-term therapy should be avoided.     

In situ assessment of porphyrin photosensitizers in Propionibacterium acnes

Porphyrins are known to be efficient photosensitizer molecules and the combined action of light and porphyrins in Propionibacterium acnes have a lethal action on the cells. Identification and quantification of in situ porphyrins in P. acnes have been done using an integrating sphere connected to an ordinary absorption spectrophotometer, and the amounts of porphyrins in the cells were quantified by measuring scattering free absorption spectra of the cell suspensions. The concentration of porphyrins in P. acnes cells were increased in either of two ways; by the addition of delta-aminolevulinic acid (ALA), which lead to the formation of coproporphyrin III under the incubation conditions used in these experiments, or by the addition of protoporphyrin IX (PPIX) to the cell suspension. In the latter case, PPIX molecules are taken up by the cells in a membrane-mediated uptake mechanism, and accumulate in the cells either on a monomeric or a particular aggregate form. The fraction of porphyrins on aggregate form increased with increasing PPIX additions. In the case of ALA induced porphyrin production, only monomeric porphyrins were stored in the cells. In both cases, the cells have a limited binding capacity of monomeric porphyrins, which is estimated to be 3 x 10(5) molecules/cell, or one porphyrin molecule to every 100st lipid molecule in the cell membrane.     

Purification and partial characterization of hyaluronate lyase (EC 4.2.2.1) from Propionibacterium acnes.

Hyaluronidase from Propionibacterium acnes has been purified 13,000-fold from the culture supernatant to homogeneity (as determined by polyacrylamide disc gel electrophoresis). The molecular weight of the purified enzyme was 85,110 as determined by gel filtration. The purified enzyme had a pH optimum at 6.4, was stable between pH 5 and 5.8 and was completely inactivated after 15 min at 50 degrees C. Preliminary studies suggested that the enzyme is active against chondroitin 4- and 6-sulphates, but not against dermatan sulphate. Analysis by paper chromatography of the reaction products from the degradation of hyaluronic acid by bacterial, testicular and P. acnes enzymes suggested that the P. acnes enzyme is similar in its mode of action to other bacterial hyaluronate lyases. The enzyme from P. acnes may thus be tentatively classified as a hyaluronate lyase.