Propionibacterium (Cutibacterium) granulosum Extracellular DNase BmdE Targeting Propionibacterium (Cutibacterium) acnes Biofilm Matrix, a Novel Inter-Species Competition Mechanism

Acne vulgaris is the most common dermatological disorder worldwide affecting more than 80% of adolescents and young adults with a global prevalence of 231 million cases in 2019. The involvement of the skin microbiome disbalance in the pathophysiology of acne is recognized, especially regarding the relative abundance and diversity of Propionibacterium acnes a well-known dominant human skin commensal. Biofilms, where bacteria are embedded into a protective polymeric extracellular matrix, are the most prevalent life style for microorganisms. P. acnes and its biofilm-forming ability is believed to be a contributing factor in the development of acne vulgaris, the persistence of the opportunistic pathogen and antibiotic therapy failures. Degradation of the extracellular matrix is one of the strategies used by bacteria to disperse the biofilm of competitors. In this study, we report the identification of an endogenous extracellular nuclease, BmdE, secreted by Propionibacterium granulosum able to degrade P. acnes biofilm both in vivo and in vitro. This, to our knowledge, may represent a novel competitive mechanism between two closely related species in the skin. Antibiotics targeting P. acnes have been the mainstay in acne treatment. Extensive and long-term use of antibiotics has led to the selection and spread of resistant bacteria. The extracellular DNase BmdE may represent a new bio-therapeutical strategy to combat P. acnes biofilm in acne vulgaris.

Green Synthesis of Conjugated Linoleic Acids from Plant Oils Using a Novel Synergistic Catalytic System

A novel and efficient method has been developed for converting plant oil into a specific conjugated linoleic acid (CLA) using a synergistic biocatalytic system based on immobilized Propionibacterium acnes isomerase (PAI) and Rhizopus oryzae lipase (ROL). PAI exhibited the greatest catalytic activity when immobilized on D301R anion-exchange resin under optimal conditions (PAI dosage of 12 410 U of PAI/g of D301R, glutaraldehyde concentration of 0.4%, and reaction conditions of pH 7.0, 25 °C, and 60 min). Up to 109 g/L trans-10,cis-12-CLA was obtained after incubation of 200 g/L sunflower oil with PAI (1659 U/g of oil) and ROL (625 mU/g of oil) at pH 7.0 and 35 °C for 36 h; the corresponding conversion ratio of linoleic acid (LA) to CLA was 90.5%. This method exhibited the highest proportion of trans-10,cis-12-CLA yet reported and is a promising method for large-scale production.

Inflammation and acne: putting the pieces together

Acne vulgaris is a common skin disease in which abnormal desquamation, excess sebum production, proliferation of Propionibacterium acnes, and production of proinflammatory mediators all contribute to the pathogenesis of the disease. A review of the literature shows that our current understanding of acne pathogenesis continues to evolve. Recent data suggests that inflammatory mediators may play a more important role than previously realized; however, how these mediators work independently as well as together in acne lesion progression is not well understood. Several cell types and mediators involved in the pathology of acne are responsible for producing or exacerbating an inflammatory response. Here, we present an updated theoretical model of acne lesion progression that highlights the role inflammatory mediators may play throughout acne lesion development.

Characterization of beta-1,3-galactosyl-N-acetylhexosamine phosphorylase from Propionibacterium acnes

Homologs of the beta-1,3-galactosyl-N-acetylhexosamine phosphorylase (GalHexNAcP) gene (gnpA) were cloned from the genomic DNA of Propionibacterium acnes JCM6425 and P. acnes JCM6473, showing 99.9% and 97.9% nucleotide sequence identity, respectively, with the ppa0083 gene from the genome-sequenced P. acnes KPA171202. No gnpA gene was detected in the genomic DNA of type strain P. acnes ATCC25746. The recombinant enzyme from P. acnes JCM6425 (GnpA) showed approximately 70 times higher specific activity of phosphorolysis on galacto-N-biose (Galbeta1-->3GalNAc, GNB) than that on lacto-N-biose I (Galbeta1-->3GlcNAc). K (m) value for GnpA on GNB was high, but GnpA did not exhibit activity on any derivatives of GNB examined. These results indicate that GnpA is GalHexNAcP which should be classified as galacto-N-biose phosphorylase. The large k (cat) value of GnpA on GalNAc suggests that GnpA would be a useful catalyst for the synthesis of GNB.

Heterologous expression of linoleic acid isomerase from Propionibacterium acnes and anti-proliferative activity of recombinant trans-10, cis-12 conjugated linoleic acid

The linoleic acid isomerase enzyme from Propionibacterium acnes responsible for bioconversion of linoleic acid to trans-10, cis-12 conjugated linoleic acid (t10, c12 CLA) was cloned and overexpressed in Lactococcus lactis and Escherichia coli, resulting in between 30 and 50 % conversion rates of the substrate linoleic acid to t10, c12 CLA. The anti-proliferative activities of the fatty acids produced following isomerization of linoleic acid by L. lactis and E. coli were assessed using the human SW480 colon cancer cell line. Fatty acids generated from both L. lactis and E. coli contained a mixture of linoleic acid and t10, c12 CLA at a ratio of ∼1.35 : 1. Following 5 days of incubation of SW480 cells with 5–20 μg ml⁻¹ (17.8–71.3 μM) of the t10, c12 CLA, there was a significant (P<0.001) reduction in growth of the SW480 cancer cells compared with the linoleic acid control. Cell viability after treatment with the highest concentration (20 μg ml⁻¹) of the t10, c12 CLA was reduced to 7.9 % (L. lactis CLA) and 19.6 % (E. coli CLA), compared with 95.4 % (control linoleic acid) and 31.7 % (pure t10, c12 CLA). In conclusion, this is believed to represent the first report in which recombinant strains are capable of producing CLA with an anti-proliferative potential.

Structure and mechanism of the Propionibacterium acnes polyunsaturated fatty acid isomerase

Conjugated linoleic acids (CLAs) affect body fat gain, carcinogenesis, insulin resistance, and lipid peroxidation in mammals. Several isomers of CLA exist, of which the (9Z, 11E) and (10E, 12Z) isomers have beneficial effects on human metabolism but are scarce in foods. Bacterial polyunsaturated fatty acid isomerases are promising biotechnological catalysts for CLA production. We describe six crystal structures of the Propionibacterium acnes polyunsaturated fatty acid isomerase PAI in apo- and product-bound forms. The three-domain flavoprotein has previously undescribed folds outside the FAD-binding site. Conformational changes in a hydrophobic channel toward the active site reveal a unique gating mechanism for substrate specificity. The geometry of the substrate-binding site explains the length preferences for C18 fatty acids. A catalytic mechanism for double-bond isomerization is formulated that may be altered to change substrate specificity for syntheses of rare CLAs from easily accessible precursors.

In-house SIRAS phasing of the polyunsaturated fatty-acid isomerase from Propionibacterium acnes

The polyenoic fatty-acid isomerase from Propionibacterium acnes (PAI) catalyzes the double-bond isomerization of linoleic acid to conjugated linoleic acid, which is a dairy- or meat-derived fatty acid in the human diet. PAI was overproduced in Escherichia coli and purified to homogeneity as a yellow-coloured protein. The nature of the bound cofactor was analyzed by absorption and fluorescence spectroscopy. Single crystals of PAI were obtained in two crystal forms. Cubic shaped crystals belong to space group I2(1)3, with a unit-cell parameter of 160.4 A, and plate-like crystals belong to the monoclinic space group C2, with unit-cell parameters a = 133.7, b = 60.8, c = 72.2 A, beta = 115.8 degrees. Both crystal forms contain one molecule per asymmetric unit and diffract to a resolution of better than 2.0 A. Initial phases were obtained by SIRAS from in-house data from a cubic crystal that was soaked with an unusually low KI concentration of 0.25 M.

Insights in the Pathogenic Potential of Propionibacterium acnes From Its Complete Genome

One of the long-lasting open questions in understanding acne is the role of the skin bacterium Propionibacterium acnes. Opinions within the scientific community diverge regarding the importance of this Gram-positive bacterium not only in acne but also in other P. acnes-associated diseases. The recently decoded genome gives us some clues with respect to its pathogenic potential and its strategies to survive in the harsh environment of human skin. This review focuses on the major findings of the genome sequence. Special attention has been drawn to the cell surface composition of P. acnes, its antigenic potential, and to enzymes that are potentially involved in degrading skin-derived substances.

Inhibition of lipase activity in antibiotic-resistant propionibacterium acnes strains

BACKGROUND AND OBJECTIVE

Erythromycin-sensitive and/or clindamycin-sensitive strains of Propionibacterium acnes show a reduced lipase production at levels below the minimal growth-inhibitory concentration (MIC). The objective of this study was to determine whether erythromycin and clindamycin concentrations far below the MIC inhibit lipase production in P. acnes strains resistant to these antibiotics.

METHODS

Of 42 P. acnes strains, 10 showed an MIC >256 micro g/ml for erythromycin. Two strains showed MICs of 0.19 and 0.25 micro g/ml, while the MIC of the remaining strains was <or=0.016 micro g/ml. Lipase activity was determined up to a concentration of 192 micro g/ml by cultivation on spirit blue agar + lipase reagent. The 10 strains whose erythromycin MIC was >256 micro g/ml were also tested for lipase inhibition by clindamycin. While this method fails to differentiate between inhibition of lipase production and inhibition of lipase activity, the absence of inhibition of lipase activity rules out inhibition of lipase production.

RESULTS

Inhibition of lipolysis by sub-MIC concentrations was demonstrated only for clindamycin in 3 P. acnes strains. However, lipase inhibition was seen only at the dilution level immediately below the MIC.

CONCLUSIONS

Resistant P. acnes strains with high erythromycin and/or clindamycin MICs can be ruled out to show in vitro inhibition of lipase production at antibiotic concentrations far below the MIC.

Propionibacterium acnes lipase in seborrheic dermatitis and other skin diseases and Unsei-in

We examined Propionibacterium acnes lipase in skin diseases and Unsei-in. Butyric acid production in axillary seborrheic dermatitis (ASD) was higher than in other dermatitis, and that in acne vulgaris (AV) was significantly higher than in controls. P. acnes lipase is the pathogenic factor in AV and fatty acids produced by lipase might be the pathogenic factor in ASD. Unsei-in suppressed P. acnes lipase probably because some ingredients have antimicrobial and anti-inflammatory activities.

Effect of lipase activities of Propionibacterium granulosum and Propionibacterium acnes

We studied the lipase activities of Propionibacterium granulosum, P. acnes and the suppression of these activities by Jumi-haidoku-to (JHT). Lipase activity of P. acnes biotype III (BIII) was strongest, while that of P. granulosum was faintly expressed. Compared with the control medium, the production of propionic and butyric acids was suppressed by all the tested mediums combined with JHT. The decrease in these acids produced by JHT was significantly higher in P. granulosum than in P. acnes. Although P. acnes BIII may produce a strong effect on acne, the presence of P. granulosum should not be ignored. Further research is required on the correlation between P. acnes and P. granulosum.

Erythromycin-resistance of cutaneous bacterial flora in acne

Some studies have raised the problem of an increase of bacterial resistance in acne patients. This study was carried out in France, where no previous studies about resistance to erythromycin has been performed, on 40 patients with mild to moderately severe acne. Microbiological samples were obtained by using Williamson and Kligman method. This study showed that the prevalence of bacterial resistance to erythromycin was 95% for Staphylococcus epidermidis strains and 52% for Propionibacterium acnes strains. Resistant strains were more frequent in patients with predominantly inflammatory lesions (papules and pustules). The influence of previous or current treatment with erythromycin was also studied and showed that even patients without any previous use of erythromycin had resistant strains for Propionibacterium acnes (42%). In addition the minimum inhibitory concentrations (MIC) for zinc were evaluated. All the Propionibacterium acnes strains tested were inhibited at concentrations less or equal to 512 mug/ml of zinc. However, zinc combined with erythromycin in vitro did not modify the erythromycin MIC. This first French study on bacterial resistance to erythromycin in acne patients confirms the results of studies performed in other countries.

Relationship between Propionibacterium acnes biotypes and Jumi-haidoku-to

We examined the relationship between Propionibacterium acnes biotypes and Jumi-haidoku-to (JHT). In all the P. acnes strains tested, the production of propionic acid (PA) and butyric acid (BA) was suppressed in a medium containing 1 mg/ml JHT compared with the control medium without JHT. There were no significant differences in the rates of decreased PA and BA production between P. acnes biotype 3 (B3) and the other biotypes or between isolates from mild skin rash and more severe skin rash. P. acnes B3 was the most commonly identified biotype. The clinical effects on acne due to the anti-P. acnes lipase activity of JHT did not seem to be influenced by the degree of acne rash or the P. acnes biotype.

Correlation between Propionibacterium acnes biotypes, lipase activity and rash degree in acne patients

We examined the possible correlation between biotypes of Propionibacterium acnes, lipase activity, and rash degree in acne patients. Among 5 P. acnes biotypes, P. acnes biotype 3 (B3) was the most common, followed by P. acnes biotypes 1, 2 and 4; P. acnes biotype 5 was not found. P. acnes B3 was isolated from more severe skin rashes than those of the other biotypes. Production of propionic acid (PA) and butyric acid (BA) by P. acnes B3 was higher than those by the other P. acnes biotypes. As the rash degree in acne patients was more severe, the production of PA and BA elevated. Although only a few P. acnes strains were examined in the present study, P. acnes B3 had the highest lipase activity and might have the greatest influence on skin rash in acne patients.

Propionibacterium acnes, a resident of lipid-rich human skin, produces a 33 kDa extracellular lipase encoded by gehA

Five independent clones of the Propionibacterium acnes P-37 lipase gene (gehA) were obtained in Escherichia coli, and the gene was localized to a 2.75 kb Xhol fragment by subcloning. The five clones were shown to contain the same gene by Southern blotting with a DIG-labelled probe to gehA. The nucleotide sequence of gehA was determined, and shown to contain a single ORF of 1017 kb, encoding a protein of 339 amino acids. The predicted molecular mass was 36 kDa. A 33 kDa (PAGE) radiolabelled polypeptide was detected from E. coli minicell preparations harbouring gehA, which could correspond to GehA after cleavage of the putative 26 amino acid residue signal peptide. gehA was overexpressed in E. coli under the control of the bacteriophage T7 promoter, and the corresponding polypeptide was found to be present in insoluble aggregates. Active lipase was produced when the overexpressing strain was incubated at a reduced temperature in the presence of sucrose. Purification of lipase from P. acnes culture supernatant fluids confirmed the production of a 33 kDa (PAGE) lipase.

Exocellular phospholipase C activity from a Propionibacterium acnes strain isolated from a periodontal pocket

The culture supernatant of a strain of Propionibacterium acnes was investigated for its phospholipase (PL) activity. The microorganism was isolated from a periodontal pocket of a patient with periodontal disease. Supernatants from cultures of this microorganism were used as a source to obtain enzymes. Proteins from the supernatants were concentrated, and their enzymatic activity was partially purified through molecular sieving. The procedure yielded two peaks of activity. This activity was shown to hydrolyze phosphatidyl choline (PC) and phosphatidyl ethanolamine (PE) and was effective in a pH range of 5 to 9, with an optimal activity at pH 7.0. Divalent cations were not required for activity of the enzymes. Analysis of the products obtained from the hydrolysis of PC labeled in the choline, phosphoryl, or acyl moieties and PE containing labeled oleic acid indicated that the supernatants' activity was mostly phospholipase C (PL-C). Phospholipase C can act synergistically with other factors to produce tissue damage, and hence may contribute to the pathogenesis of periodontal disease.

Anti-lipase activity of Kampo formulations, coptidis rhizoma and its alkaloids against Propionibacterium acnes

Anti-lipase activity of Kampo formulations, Coptidis Rhizoma (CR), and its alkaloids against Propionibacterium acnes were examined in vitro. The amounts of propionic and butyric acids in the medium were measured as growth and lipase activity of P. acnes, respectively. In tributyrin-PYG medium with each concentration of Kampo formulation, CR, or the alkaloids added, the production of propionic acid was suppressed remarkably more than that of butyric acid. The suppression of production of these acids by CR was higher than that of the alkaloids. Furthermore, no lipase-negative colonies were found on the medium to which Kampo formulations were added. From these observations, we concluded that not only Kampo formulations and CR, but also their alkaloids, showed suppression of growth of P. acnes, which reduced anti-lipase activity. Furthermore, it was suggested that Kampo formulations and Kampo crude drugs with anti-lipase activity to P. acnes should be synergistic when their ingredients are combined.

A zymographic assay for detection of hyaluronidase activity on polyacrylamide gels and its application to enzymatic activity found in bacteria

A zymographic assay for the determination of hyaluronidase activity in cell-free extracts on native polyacrylamide gels has been developed. In this assay an agarose replica of the polyacrylamide gel which contains hyaluronic acid and bovine serum albumin (BSA) was used. After an incubation at 37 degrees C to allow transfer and development of enzymatic activity, the hyaluronic acid and BSA were precipitated in the agarose gel with 2 M acetic acid. Areas of enzymatic activity appeared as clear zones in the agarose replica. The assay was sensitive and was used to demonstrate hyaluronidase activity in cell-free extracts from a number of bacterial and mammalian species.

Invasion of Streptococcus mutans, Streptococcus intermedius and Propionibacterium acnes into the teeth of gnotobiotic rats

Germ-free rats, fed a modified cariogenic diet 2000 with a reduced sucrose content of 25%, were inoculated with a strain of Streptococcus mutans, Streptococcus intermedius or Propionibacterium acnes, respectively. After 100 days on the diet, the rats were sacrificed. Microscopic examination of stained decalcified tooth sections revealed marked destruction of the outer zones of the dentin infected with S. mutans. The destruction was closely associated with the formation of glucan-mediated large aggregates of S. mutans. The aggregates, however, were rarely formed in the deep zones of the infected dentin. Inoculation with S. intermedius and P. acnes had little effect on the microscopic outline of the decalcified tooth sections. However, the staining behavior of the sections with Mallory's method, Alcian blue-PAS and silver was like that of the tooth sections infected with S. mutans, even in the central and inner zones of the dentin. The histochemical alterations of the deep zones of the dentin induced by the three infected bacteria appeared to be due to their proteolytic rather than to their acidogenic activities.

[The influence of coptidis rhizoma to lipase activity of Propionibacterium acnes]

Gas chromatography was applied for determination of the amounts of propionic and butyric acids in the medium produced by Propionibacterium acnes. The organism was incubated in Peptone-Yeast extract-Glucose medium containing 0.017 mEq/ml of tributyrin and various amounts of Coptidis Rhizoma at 37 degrees C for 24 to 96 hr. The amount of butyric acid produced by the lipase was reduced parallel with that of propionic acid resulted from the growth of P. acnes in the medium. These facts were also confirmed by counting the cell numbers of P. acnes. Furthermore, any lipase-negative colonies were not observed on the Kishishita's Lipase Medium. These findings indicate that Coptidis Rhizoma inhibits growth of P. acens and anti-lipase activity of the drug against the organism is resulted from the fact.

Contribution of the microflora to proteolysis in the human large intestine

Protease activities in human ileal effluent were approximately 20-fold greater than in normal faeces. Comparative studies with faeces from a person who did not have a pancreas suggested that a substantial proportion of the proteolytic activity in normal faeces was of bacterial origin. Thimerosal, iodoacetate, EDTA and cysteine significantly inhibited proteolysis in faeces, but not in small intestinal contents, showing that cysteine and metalloproteases were produced by bacteria in the large gut. These results, together with results from studies using p-nitroanilide substrates, demonstrated that faecal proteolysis was both qualitatively and quantitatively different from that in the small intestine. Studies with pure cultures of proteolytic gut bacteria indicated that the cell-bound proteases of Bacteroides fragilis-type organisms were likely to contribute significantly towards proteolytic activity associated with the washed cell fraction and washed particulate fraction of faeces. Extracellular proteases were formed by Streptococcus faecalis ST6, Propionibacterium acnes P6, Clostridium perfringens C16, Cl. bifermentans C21 and Cl. sporogenes C25. Inhibition results suggested that these bacteria, and similar organisms, may be partly responsible for the extracellular proteolytic activity found in the cell-free supernatant fraction of faeces.

Antibodies to P. acnes and P. acnes exocellular enzymes in the normal population at various ages and in patients with acne vulgaris

Total serum IgM and IgG agglutinins to P. acnes and neutralizing antibodies to P. acnes lipase, hyaluronate lyase and acid phosphatase were measured in normal individuals of different age groups. Agglutinins to P. acnes were detected in infants at 4 months of age and were present at a high level throughout life. A switch from predominantly IgM agglutinins in children, to IgG agglutinins in adults, occurred during adolescence. Anti-P. acnes lipase antibodies were present in 20% of teenagers and 17-42% of adults. Anti-P. acnes hyaluronate lyase antibodies were found in adults only (4-17%). Antibodies to acid phosphatase were not detected. Agglutinins to P. acnes were measured in individuals with mild, moderate and severe acne, and in normal controls. Only patients with severe acne had significantly higher titres than the controls. IgM and IgG agglutinins were determined in 13-14-year-olds with mild, moderate and severe acne, and in normal controls. Thirty-three per cent, 60% and 100% of the acne patients, respectively, but none of the normal controls, had predominantly IgG agglutinins. No difference in the prevalence or titre of antibodies to P. acnes exocellular enzymes was observed when patients with severe acne were compared with normal controls. There was no evidence to suggest a role for antibodies to P. acnes exocellular enzymes in the initiation of inflammatory acne.

Bacterial lipases and chronic blepharitis

Eyelids and conjunctivae of 36 normal individuals and 60 patients from six clinical groups of chronic blepharitis were cultured for aerobic and anaerobic bacteria. The most common species isolated were coagulase-negative staphylococci (C-NS) and Propionibacterium acnes. All strains of these species, and all Staphylococcus aureus strains isolated were tested for the ability to break down triglycerides, cholesterol esters, and fatty waxes. Each strain was incubated independently with appropriate substrates in nutrient media. Each medium was then extracted and assayed for the presence of substrate hydrolysis products by thin-layer chromatography. The percentage of strains capable of hydrolyzing a particular substrate was determined for each individual. S. aureus was a consistent and strong lipase producer, able to hydrolyze all three substrates. P. acnes was able to hydrolyze triolein and behenyl oleate but not cholesteryl oleate. No differences were observed among groups for P. acnes or S. aureus. C-NS showed a high degree of strain variability. Eighty-three percent of C-NS strains could hydrolyze triolein, 82% behenyl oleate, and 40% cholesteryl oleate. Significant group differences were seen in the percentage of lipase positive C-NS strains isolated per individual. Patients in the mixed staphylococcal/seborrheic, meibomian seborrheic, secondary meibomitis, and the meibomian keratoconjunctivitis (MKC) groups harbored significantly more C-NS strains capable of hydrolyzing cholesteryl oleate than did normal individuals. Patients in the meibomian seborrheic, secondary meibomitis, and MKC groups harbored significantly more C-NS strains capable of hydrolyzing behenyl oleate than did normals. No group differences were seen among groups with triolein hydrolyzing C-NS strains.

Purification and properties of a proline iminopeptidase from Propionibacterium acnes

Proline iminopeptidase was extracted from the cells of a strain of Propionibacterium acnes and purified. The molecular weight was estimated to be about 120,000 by SDS-polyacrylamide gel electrophoresis. The enzyme showed the highest activity at 50 degrees C-55 degrees C and its optimum pH was found at 7.5-8.0. The enzyme activity was inhibited by p-chloromercuribenzoate, indicating that this peptidase is a SH-enzyme. Especially prolyl-glycyl-glycine but also prolyl-proline bonds were hydrolyzed by this enzyme, glycyl-proline was not split.

Effects of dilution rate on biomass and extracellular enzyme production by three species of cutaneous propionibacteria grown in continuous culture

Propionibacterium acnes, P. avidum and P. granulosum were grown in continuous culture at a range of dilution rates on a semi-synthetic medium. Dilution rates were chosen to allow the bacteria to grow at the same relative growth rates as compared to their respective mumax values. The steady-state levels and production rates of biomass and extracellular enzymes were determined. The lipase and hyaluronate lyase of P. granulosum and the proteolytic activity of P. acnes and P. avidum were growth linked enzymes (i.e. they were produced at constant amounts per unit of biomass). In contrast, the lipase, hyaluronate lyase and acid phosphatase of P. acnes and the lipase of P. avidum were shown to be non-growth linked enzymes.

Study of elastolytic activity Propionibacterium acnes and Staphylococcus epidermis in acne vulgaris and in normal skin

Histopathological sections of anetoderma-like scars from 10 patients with acne vulgaris showed a selective absence of elastic fibers around pilosebaceous follicles. This finding is similar to the histologic changes of "perifollicular elastolysis" reported by Varadi. Bacteria isolated by anaerobic and aerobic cultures of swabs of the skin surface and pus of these 10 patients, 12 others with active acne vulgaris and 8 normal subjects were studied with particular attention to Staphylococcus epidermis and Propionibacterium acnes. These organisms were analysed for production of an elastolytic enzyme which might play a role in the observed selective loss of elastic fibers. No elastolytic activity was produced by S. epidermidis or P. acnes isolated from any of these individuals. Thus, we cannot attribute the perifollicular loss of elastic fibers in acne scarring to an elastase produced by organisms. The observed absence of elastic fibers might result from tissue necrosis produced by leukocytes during the inflammatory phase, followed by collagenous scar formation without regeneration of elastic fibers.

Phospholipase C of an oral strain of Propionibacterium acnes purification and partial characterization

Phospholipase C of the oral Propionibacterium acnes strain D 7 was purified from culture supernatants and partially characterized. The molecular weight was found to be 32.000 and the optimum pH was situated between 7.0 to 8.0. This nonhemolytic enzyme hydrolyzed relative intensively acidic glycerophospholipids and produced 1,2-diglyceride from phosphatidyl choline.

Difficulties in producing antibodies to purified Propionibacterium acnes exocellular enzymes

Attempts were made to produce antisera to purified preparations of Propionibacterium acnes lipase, hyaluronate lyase and acid phosphatase in rabbits. Antiserum to lipase (neutralizing titre I:32) was produced using conventional methods. Lipase (30 micrograms) in Freund's complete adjuvant (FCA) was injected into multiple sites thrice at weekly intervals. Antibody levels were boosted by i.v. injections of 30 micrograms in saline at 2-weekly intervals for 2 months. Such regimes failed to raise antibodies to hyaluronate lyase and acid phosphatase. In order to produce antiserum to hyaluronate lyase, rabbit mononuclear cells were incubated with 45 micrograms of hyaluronate lyase in vitro (I h at 37 degrees C) prior to injection subcutaneously above the rabbit ankle joint. Simultaneous injections of hyaluronate lyase in FCA (45 micrograms) were administered into the footpad and thigh. Three treatments at weekly intervals produced an antiserum with a neutralizing titre of I:256. A similar regime failed to raise antibodies to acid phosphatase. Antibodies to P. acnes lipase and hyaluronate lyase also neutralize the enzymes produced by P. granulosum. The neutralization curves suggest that the enzymes produced by both species are related antigenically but not identical.

Effects of oxygen concentration on biomass production, maximum specific growth rate and extracellular enzyme production by three species of cutaneous propionibacteria grown in continuous culture

Propionibacterium acnes, Propionibacterium avidum and Propionibacterium granulosum were grown in continuous culture at 0-100% air saturation using a semi-synthetic medium. Maximum specific growth rate, biomass concentration and extracellular lipase, hyaluronate lyase and phosphatase activities were determined. All three species were capable of growth at 100% air saturation but at reduced growth rates. The presence of oxygen altered the production of extra-cellular enzymes. Propionibacterium avidum was the best adapted for growth in aerobic environments.

Effects of pH on biomass, maximum specific growth rate and extracellular enzyme production by three species of cutaneous propionibacteria grown in continuous culture

Three cutaneous propionibacteria, Propionibacterium acnes, Propionibacterium avidum and Propionibacterium granulosum, were grown in chemostats using semi-synthetic medium at various pH values. Growth occurred between pH 4.5 and 7.5 for P. acnes and pH 5.0 and 8.0 for P. avidum and P. granulosum. The highest mumax was at pH 6.0 for the three species. Maximum biomass production was obtained at pH 6.0 for P. acnes and P. avidum and at pH 7.5 for P. granulosum. Extracellular enzyme production occurred over the entire pH growth range when denaturation of the enzymes was taken into account. However, detectable activity of the enzymes was found in a narrower range of pH due to the denaturation of the enzymes at low or high pH values. The highest production of enzymes occurred at pH values between 5.0 and 6.0, apart from the production of hyaluronate lyase of P. granulosum (pH 6.0 to 7.0) and the proteinase of P. acnes and P. avidum (pH 5.0 to 7.5). Propionibacterium acnes produced a lipase, hyaluronate lyase, phosphatase and proteinase activity. Propionibacterium avidum produced a lipase and proteinase activity. Propionibacterium granulosum produced a lipase and hyaluronate lyase.

Exoenzymes of Propionibacterium acnes

Thirty strains of Propionibacterium acnes were grown in basal salt medium containing lecithin as a lipid substrate and in other media. The cultures were assayed for production of lipase (measured as fatty acid esterase) and other exoenzymes. Lipase was assayed spectrophotometrically; other enzymes were assayed using the API ZYM system (Analytab Products Inc., Plainview, NY). Substance for lipase were alpha- and beta-naphthol esters of propionic, butyric, valeric, caprylic, lauric, myristic, and oleic acids. All strains showed fatty acid esterase activity. Using the API ZYM system 19 enzymes were detected, 8 of which were found frequently and had high activity in most strains. Acid and alkaline phosphatases, phosphoamidase, ester lipase, trypsin-chymotrypsin-like proteases, beta-glucuronidase (80%), beta-galactosidase (80%), and N-acetyl-beta-glucosaminidase were found. Many enzymes of P. acnes appear to be adaptive, dependent on the culture substrate.

Neutrophil chemotaxis by Propionibacterium acnes lipase and its inhibition

The chemoattraction of Propionibacterium acnes lipase for neutrophils and the effect of lipase inhibitor and two antibiotic agents on the chemotaxis were evaluated. Of the various fractions tested, partially purified lipase (fraction 2c) was the most active cytotaxin produced by P. acnes. Serum mediators were not required for the generation of chemotaxis by lipase in vitro. Diisopropyl phosphofluoridate at low concentration (10(-4) mM) completely inhibited lipase activity as well as polymorphonuclear leukocyte chemotaxis generated by lipase. Tetracycline hydrochloride and erythromycin base at concentrations of 10(-1) mM and 1 mM, respectively, caused 100% inhibition of PMN migration toward lipase or zymosan-activated serum. The inhibiting activity of the antibiotics was directed against cells independently of any effect on lipase. Chemotaxis by P. acnes lipase suggests a wider role for this enzyme in the inflammatory process and the pathogenesis of acne vulgaris.

Partial purification and characterization of lipase (EC 3.1.1.3) from Propionibacterium acnes

Lipase from Propionibacterium acnes has been purified 4800-fold from crude culture supernatant. The purified enzyme preparation had no assayable protease, hyaluronate lyase or acid phosphatase activities. The molecular weight of the lipase was 46,770 as determined by gel filtration. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed a major protein component (mol. wt 41,190) together with two minor protein components (mol. wt 67,000 and 125,900). The lipase had a pH optimum of 6.8, was most stable in the pH range 5.0 to 6.0 and was completely inactivated after 30 min at 60 degrees C. The lipase hydrolysed trilaurin, triolein, trimyristin and tripalmitin at decreasing rates and did not exhibit phospholipase activity. Analysis of the reaction products from the hydrolysis of triolein by P. acnes lipase did not demonstrate an accumulation of 2-monoolein which suggested that the enzyme did not exhibit a positional specificity for the 1-position of the triacylglycerol. Crude lipase preparations contained an aggregated high molecular weight form of the enzyme which was eluted with the void volume from Sephadex G-200. This aggregated form was dissociated to produce the lower molecular weight lipase species by subsequent dialysis and elution from Sephadex G-200 using buffer with a higher ionic strength.

Kinetic parameters of lactate dehydrogenases of some rumen bacterial species, the anaerobic ciliate Isotricha prostoma and mixed rumen microorganisms

A number of kinetic parameters of the lactate dehydrogenases of three rumen bacterial species (Peptostreptococcus productus, Propionibacterium acnes and Actinomyces viscosus), the rumen ciliate Isotricha prostoma and mixed rumen microorganisms (MRM) with respect to NADH, pyruvate, fructose-1,6-diphosphate (FDP) as well as the effects of several nucleotide phosphates were studied. Partially purified LDH of Peptostr. productus had the same kinetic parameters as in crude cell free extracts. Values for Km, determined by Michaelis-Menten kinetics with pyruvate as the substrate, were in the same range for all lactate dehydrogenases. After feeding a cow, changes in the apparent Km and Vmax values for NADH of the total LDH activity in MRM were followed. It is suggested that of the factors studied the ratio NADH/NAD(H) and ATP are the most important regulatory factors for the lactate dehydrogenases of mixed rumen microorganisms.

Isolation, purification, and properties of neuraminidase from Propionibacterium acnes

Neuraminidase activity was discovered in 32 of 38 strains of Propionibacterium acnes. Enzyme production was studied in yeast extract bouillon of different pH containing various amounts of human milk as neuraminidase inductor. Enzyme activity was found in the bacterial sediments as well as in the culture filtrates. Since neither ultrasonic treatment nor lysozyme incubation of bacterial sediments did release reasonable amounts of enzyme, culture filtrates were used for enzyme preparation. Neuraminidase was isolated by 40% ammonium sulfate precipitation, dialysis, concentration and repeated gel chromatography on Sephadex G-100. The enzyme posesses a molecular weight of about 33 000 and a pH-optimum around 5.0. The Michaelis constants are 1.8 x 10(-3) M for alpha 2 leads to 3 linked N-acetylneuraminic acid (NeuAc) in II3NeuAc-Lac, 3.7 x 10(-3) M for the alpha 2 leads to 6 linkage in II6NeuAc-Lac, and 2.1 x 10(-3) M for the alpha 2 leads to 8 linkage of II3 (comes from 2 alpha NeuAc8)2-Lac, respectively. Among the different groups of naturally occurring NeuAc-containing substrates, i.e. oligosaccharides, glycolipids and glycoproteins, the enzyme exhibits its highest activity towards low molecular weight oligosaccharides. Activity is considerably lower on glycoproteins. Glycolipids (gangliosides) are only little attacked under conditions used in the test. However, there is no remarkable specificity towards one of the different linkage types of N-acetylneuraminic acid. In general, the enzyme reveals a specificity pattern similar to that found in other bacteria of low pathogenicity towards man.

Purification and partial characterization of an acid phosphatase (EC 3.1.3.2) produced by Propionibacterium acnes

A strain of Propionibacterium acnes (type I; Marples & McGinley, 1974), isolated from a blackhead acne lesion, produced an acid phosphatase which was present in the culture supernatant in the late-exponential and early-stationary phases of growth. This acid phosphatase was purified more than 45 000-fold (4.5% yeild). The purified enzyme gave two protein bands on sodium dodecyl sulphate-polyacrylamide gel electrophoresis corresponding to molecular weights of 155 000 and 87 100. The enzyme had a single peak of activity on Sephadex G-100, with a molecular weight corresponding to 93 000. The highly purified acid phosphatase had an optimum activity at pH 5.8, was stable from pH 4.0 to 5.5 and was totally inactivated after 30 min at 55 degrees C. The enzyme did not show an absolute requirement for metal ions, but was stimulated by Mg2+, Ca2+, Zn2+ and K+ at concentrations between 0.1 and 1 mM. The acid phosphatase was active against a number of monophosphate esters.

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.

Production of hyaluronidase by propionibacteria from different origins

114 strains of anaerobic and microaerophilic coryneform bacteria from different origins were investigated for production of free extracellular hyaluronidase (hyaluronate glycanohydrolase, EC 3.2.1.36). A quantitative technique was applied measuring the release of N-acetyl-glucosamine groups from purified human potassium hyaluronate. The strains belonged to the following species: Propionibacterium acnes, P. avidum, P. granulosum, P. lymphophilum, the formerly so-called Corynebacterium parvum, P. freudenreichii subsp. freudenreichii and shermanii, P. thoenii, P. acidi-propionici, C. minutissimum, and Arachnia propionica. All together, 59 out of 114 (approximately 51.8%) tested strains showed clearly measurable hyaluronidase activities. P. acnes, the propionibacterium species most frequently found in acne vulgaris lesions, proved to be the most active species tested, 44 out of 64 (approximately 68.8%) P. acnes strains being positive. 5 strains producing hyaluronate glycanohydrolase activities of more than 60 mU/ml in thioglycollate broth cultures could be detected. P. avidum and P. granulosum strains were positive in only 45.0% and 33.3%, respectively, and their mean hyaluronidase activities were significantly lower. Differences in hyaluronidase activities of P. acnes strains isolated from acne vulgaris lesions and strains from normal human skin could not be found. The possible pathogenic role of propionibacteria hyaluronidase in acne vulgaris is discussed.

Low trimethoprim susceptibility of anaerobic bacteria due to insensitive dihydrofolate reductases

All the 28 Bacteroides fragilis strains investigated were susceptible to sulfamethoxazole (minimal inhibitory concentration < 16 mug/ml) and resistant to trimethoprim (TMP; minimal inhibitory concentration > 4 mug/ml). Synergism between sulfamethoxazole and TMP was present in all strains at a ratio of 1:1. The few clostridia investigated proved more resistant to both compounds. Dihydrofolate reductases from B. fragilis, C. perfringens, and some other anaerobic species were isolated. Inhibition profiles with six structurally different inhibitors revealed major differences in all enzymes. For 50% inhibition, the enzyme from B. fragilis and all clostridia required concentrations of TMP which were between several hundredfold and 1,000-fold higher than those required for the enzyme of Escherichia coli, whereas the enzyme from Propionibacterium acnes only needed a threefold higher concentration. In vitro activities of TMP were seen to correspond to the activity at the enzymatic level in B. fragilis and P. acnes, but correspond to a much lesser extent to the activity at the enzymatic level in clostridia, where a poor penetration is assumed to be involved. Dihydrofolate reductase inhibitors other than TMP were found to be as active as TMP both at the enzyme and in vitro. In B. fragilis, higher concentrations of exogenous thymidine were required for increasing the minimal inhibitory concentration of TMP than in E. coli and probably also in C. perfringens.

Electrophoretic protein patterns and enzyme mobilities in anaerobic coryneforms

The soluble protein patterns and electrophoretic mobilities of malate and succinate dehydrogenases and catalase have been examined in 25 strains of Propionibacterium acnes, P. granulosum, and P. avidum. A distinctive protein pattern for each species was found, and it was possible also to distinguish the serotypes within P. acnes and P. avidum. Strains of P. acnes, P. granulosum, and P. avidum could be differentiated by the mobilities of their malate dehydrogenases. Catalase activity was detected in the soluble fractions of all strains. Catalases from P. acnes and P. avidum strains had the same mobility, whereas that from P. granulosum was slightly slower. Under the conditions used, succinate dehydrogenase activity could be detected, but the patterns were not distinctive.

Enzymatic and hemolytic properties of Propionibacterium acnes and related bacteria

The production of chondroitin sulfatase, hyaluronidase, deoxyribonuclease, gelatinase, phosphatase, lecithinase, and hemolysins was examined in 95 strains of Propionibacterium acnes and four related species of anaerobic, respectively, microaerophilic coryneform bacteria (P. avidum, P. lymphophilum, P. granulosum, and Corynebacterium minutissimum). All enzymes could be demonstrated in at least one representative of the species tested. Those Propionibacterium species most frequently found in acne vulgaris lesions, i.e., P. acnes and P. granulosum, proved to be the most active organisms concerning the production of the enzymes tested. P. avidum, on the other hand, showed the highest rate of hemolytic activity.