1 Department of Microbiology and Immunobiology, School of Medicine, Queen's University, Grosvenor Road, Belfast BT12 6BN, UK
2 School of Biology and Biochemistry, Medical Biology Centre, 97 Lisburn Road, Queen's University, Belfast BT9 7BL, UK
3 QUESTOR Centre, Queen's University, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK
4 Corixa Corporation, Infectious Disease Institute, Seattle, WA 98104, USA
Correspondence
Sheila Patrick
s.patrick{at}qub.ac.uk
![]() |
ABSTRACT |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
The GenBank/EMBL/DDBJ accession numbers for the CAMP factor sequences of P. acnes strains NCTC 737 (IA), KPA171202 (IB), NCTC 10390 (II) and SG2 (II) are given in Table 3.
Present address: Institute of Medical Technology, University of Tampere, Finland.
Present address: Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, UK.
Present address: School of Pharmacy, Queen's University, Belfast, UK.
||Present address: Withers Orthopaedic Unit, Musgrave Park Hospital, Belfast, UK.
![]() |
INTRODUCTION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Studies by Johnson & Cummins (1972) first revealed two distinct phenotypes of P. acnes, known as types I and II, based on serological agglutination tests and cell-wall sugar analysis. Recently, recA-based sequence analysis has revealed that P. acnes types I and II represent phylogenetically distinct groups (McDowell et al., 2005
). Furthermore, a small subgroup of phylogenetically distinct type I strains with atypical mAb labelling characteristics, which we now designate type IB to distinguish them from other type I strains, designated type IA, were also described. The observation that the phenotypic differences between strains of the various P. acnes types reflect deeper differences in their phylogeny raises the possibility that they may also display variation in their expression of putative virulence factors.
P. acnes produces a co-haemolytic reaction with both sheep and human erythrocytes (Choudhury, 1978) similar to the ChristieAtkinsMunch-Petersen (CAMP) reaction first demonstrated in 1944 (Christie et al., 1944
). The CAMP reaction describes the synergistic haemolysis of sheep erythrocytes by the CAMP factor from Streptococcus agalactiae and the
-toxin (sphingomyelinase C) from Staphylococcus aureus, with the CAMP factor demonstrating non-enzymic affinity for ceramide (Bernheimer et al., 1979
). Examination of sphingomyelinase-treated sheep erythrocytes has revealed the formation of discrete membrane pores by recombinant Streptococcus agalactiae CAMP factor (Lang & Palmer, 2003
). In addition to the extensive study of the CAMP factor of Streptococcus agalactiae (Bernheimer et al., 1979
; Brown et al., 1974
; Jurgens et al., 1985
, 1987
; Ruhlmann et al., 1988
; Skalka et al., 1980
), a number of other Gram-positive and Gram-negative bacteria are known to produce a positive CAMP reaction, including Pasteurella haemolytica (Fraser, 1962
), Aeromonas species (Figura & Guglielmetti, 1987
), some Vibrio species (Kohler, 1988
) and group G streptococci (Soedermanto & Lammler, 1996
). Some of these species can also use phospholipase C (
-toxin) from Clostridium perfringens or phospholipase D from Corynebacterium pseudotuberculosis as a co-factor for haemolysis in addition to the Staphylococcus aureus
-toxin (Frey et al., 1989
). The CAMP factor genes of Actinobacillus pleuropneumoniae and Streptococcus uberis have also been identified, cloned and expressed in Escherichia coli (Frey et al., 1989
; Jiang et al., 1996
).
The precise role of the CAMP molecule in bacterial virulence remains unclear. It is likely that the co-haemolytic reaction represents a laboratory phenotype, or epiphenomenon, that is convenient for CAMP factor detection, but which may not be directly related to the role of the molecule in colonization and pathogenesis. The CAMP factor from Streptococcus agalactiae binds to the Fc region of IgG and IgM molecules, similar to the binding of IgG by Staphylococcus aureus protein A (Jurgens et al., 1987), and partial amino acid sequence similarity between the CAMP factor protein of Streptococcus agalactiae and Staphylococcus aureus protein A has been demonstrated (Ruhlmann et al., 1988
). We now present evidence of differences amongst P. acnes types IA, IB and II in the expression of proteins with sequence similarity to the CAMP co-haemolysin.
![]() |
METHODS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Bacterial culture.
All anaerobic strains were grown on anaerobic blood agar (ABA) (CM0972; Oxoid) or in brain heart infusion (BHI) (CM225; Oxoid) broth. Cultures were incubated at 37 °C in an anaerobic cabinet (MACS MG 1000; Don Whitley Scientific), in an atmosphere of 80 % N2, 10 % CO2 and 10 % H2. All Staphylococcus and Streptococcus strains were also grown at 37 °C on blood agar (BA). E. coli DH5 was grown aerobically on LuriaBertani agar plates at 37 °C. Isolates of P. acnes were routinely identified using the API 20A multitest identification system (bioMérieux) in accordance with the manufacturer's instructions.
Co-haemolysis assay.
Co-haemolytic activity was monitored by a modification of the classical co-haemolysis reaction on sheep BA plates as originally described (Christie et al., 1944). Briefly, the Staphylococcus aureus strain ATCC 25923 was streaked vertically onto sheep BA and the test strain was then streaked horizontally outwards from either side, starting close to, but not touching, the Staphylococcus aureus streak. Plates were incubated anaerobically at 37 °C for 48 h. A butterfly-shaped zone of lysis at the junction of the streaks was caused by the co-effect of diffusing Staphylococcus aureus
-toxin and co-haemolytic factor.
Production of mAb and rabbit polyclonal antisera.
The mAb QUBPa4 was generated using the protocol described previously (Harlow & Lane, 1988; Tunney et al., 1999a
). Four BALB/c mice were immunized with killed whole cells (108 c.f.u. ml1) of P. acnes. The hybridoma cell line producing QUBPa4 was then cloned by limiting dilution (Harlow & Lane, 1988
).
Rabbit polyclonal antisera were prepared against the five CAMP proteins using recombinant products expressed in E. coli. CAMP genes were amplified from P. acnes NCTC 737 genomic DNA and subcloned into the plasmid vector pET17b (Stratagene). Ligation products were first transformed into E. coli XL-1 Blue competent cells (Stratagene) and the plasmid DNA isolated from XL-1 Blue transformants was subsequently transformed into E. coli BL21 (DE3) pLysE or pLysS host cells (Novagen). The recombinant proteins were expressed in E. coli with a poly-histidine tag at the N terminus and were purified from IPTG-induced batch cultures, in the presence of 8 M urea, by affinity chromatography using the one-step QIAexpress Ni-NTA agarose matrix (Qiagen). Purity of the recombinant proteins was assessed by SDS-PAGE, followed by Coomassie brilliant blue staining and N-terminal sequencing using Edman chemistry with a Procise 494 protein sequencer (Perkin-Elmer Applied Biosystems). All recombinant proteins were assayed for endotoxin contamination using the Limulus amoebocyte assay (BioWhittaker) and shown to contain less than 50 endotoxin units mg1. Polyclonal rabbit antiserum was raised against all recombinant proteins by injecting New Zealand white rabbits (R&R rabbitry) with 200 µg purified recombinant protein in incomplete Freund's adjuvant (IFA) plus 100 µg muramyl dipeptide (Sigma). Serum was collected following two subsequent boosts separated by 3 weeks with 100 µg protein in IFA. As a result of problems with stability of the CAMP factor 1 and 5 recombinant proteins, only an N-terminal fragment of the CAMP 1 protein and N-terminal and C-terminal fragments of the CAMP 5 protein were used for immunization.
Patient serum.
Serum was prepared from venous blood (10 ml) taken pre-operatively from patients about to undergo either primary or revision total hip arthroplasty at Musgrave Park Hospital, Belfast, and from acne patients attending a Dermatology outpatients clinic in the Royal Victoria Hospital, Belfast. These procedures were approved by the local ethical committee and all patients gave full consent.
Immunofluorescence microscopy (IFM).
IFM was carried out as described previously (Patrick et al., 1995) with minor modification. Briefly, bacterial cultures were grown on ABA or BA and a suspension of 108 c.f.u. ml1 was prepared in 0·01 M PBS (0·15 M NaCl, 0·0075 M Na2HPO4, 0·0025 M NaH2PO4.2H2O; pH 7·4). Samples (10 µl) were then applied to multiwell slides, air-dried and fixed in 100 % methanol for 10 min at 20 °C. Undiluted hybridoma cell culture supernatant containing mAb QUBPa4 (30 µl) was added to each well of the slides and incubated for 45 min at 37 °C. After washing in 0·01 M PBS for 20 min at room temperature, a 1 : 100 dilution of a fluorescein isothiocyanate (FITC)-conjugated goat anti-mouse antibody (Sigma) in PBS containing 0·1 % (w/v) Evans Blue (Merck Sharp & Dome) counterstain (30 µl) was applied to each well and incubated for 45 min at 37 °C. Control wells in which primary antibody was replaced with PBS were routinely included to monitor non-specific binding of the secondary antibody. Slides were then washed and mounted in glycerol-PBS, containing an anti-photobleaching agent (Citifluor; Agar Scientific), and examined using a Leitz Dialux 20 fluorescence microscope.
Preparation of bacterial extracts.
To obtain efficient extraction and reproducible recovery of loosely cell-associated and secreted CAMP factor 1, standardized whole cell bacterial preparations of 1x1010 c.f.u. ml1 were obtained by suspending a culture grown for 6 days on ABA directly into PBS, such that a 1 : 100 dilution had an OD600 of 0·3. Cells were then disrupted by ultrasound (Soniprep 150; 26 µm amplitude) for 5 min at 4 °C. The sonicated suspension was brought to room temperature and Tween 20 (Bio-Rad) was added to a final concentration of 2 mM. The sample was then centrifuged and the resulting pellet discarded. Sodium azide was added to the supernatant (final concentration 0·02 % v/v) before storage at 20 °C.
To investigate the presence of secreted CAMP factor 1 protein in culture supernatant, bacteria were grown in BHI broth for 24 h and then centrifuged at 2370 g for 30 min (Mistral; MSE) at room temperature and the supernatant retained. An equal volume of ice-cold ethanol was then added to the supernatant followed by overnight incubation at 4 °C. The precipitated material was recovered by centrifugation at 12 000 g for 30 min (Sorvall) and the pellet was resuspended in 500 µl distilled water.
SDS-PAGE and immunoblotting.
Bacterial extracts, prepared as detailed above, were analysed using 9 % SDS-PAGE gels (Laemmli, 1970) and the resolved proteins were visualized using a silver staining kit (Amersham Pharmacia Biotech). To afford standardization and comparison of different P. acnes isolates for CAMP factor 1 expression, the colour development was carried out for between 110 and 120 s. Gels were washed three times for 5 min each in distilled water, placed in a drying solution [30 % (v/v) ethanol, 5·3 % (v/v) glycerol] for two periods of 30 min and preserved between cellophane sheets. The gels were then photographed using a Kodak DC290 digital camera fitted on a Kodak EDAS290 gel imaging hood and images were analysed using Kodak IK image analysis software version 3.5. Known positive and negative strains were included in each experiment as internal controls and indicated that the experimental system was reproducible.
Immunoblotting was carried out as described previously with a minor modification (Patrick & Lutton, 1990). In brief, nitrocellulose was blocked with 0·01 M PBS containing 0·05 % (v/v) Tween 20 (PBST) and 5 % (w/v) non-fat milk powder (Marvel; Premier brands). After washing with PBST, the nitrocellulose was incubated in undiluted mAb supernatant or an appropriate dilution of polyclonal antiserum in PBS. The nitrocellulose was then washed in PBST before incubation with alkaline phosphatase-conjugated goat anti-human IgG (H), anti-mouse IgG (H+L) or anti-rabbit IgG (H+L) (Sigma). Controls in which the primary antibody was replaced by PBS were routinely included to monitor non-specific binding of the secondary antibody. Bound antibodies were detected using an alkaline phosphatase conjugate substrate kit containing nitroblue tetrazolium and 5-bromo-4-chloro-3-indolyl phosphate (Bio-Rad).
Purification and analysis of CAMP factor 1 protein.
The mAb QUBPa4 was purified using a HiTrap protein G column (Amersham Biosciences), concentrated by ultrafiltration and immobilized on CNBr-activated agarose (Sigma). The antibody gel was packed into a column and equilibrated with PBS. Extracts of ABA-grown P. acnes (isolate SG2), prepared as detailed above, were diluted in PBS and recycled through the column overnight. The bound antigen was released with 100 mM glycine/HCl buffer, pH 2·7, and immediately neutralized with 1 M Tris before storage at 20 °C. For trypsin digestion, the eluted fractions from the affinity chromatography column, containing approximately 120 µg purified protein, were pooled and dialysed against distilled water at 4 °C overnight. The sample was then lyophilized using a Speed-Vac (Savant), the precipitate dissolved in 20 µl 8 M urea, 0·4 M NH4CO3 and the pH adjusted to between 7·5 and 8. DTT (0·25 µmol) was added and the suspension was incubated at 50 °C for 15 min. After cooling to room temperature, iodoacetic acid (0·5 µmol) was added and the suspension was incubated at room temperature for a further 15 min. The final concentration of urea was then reduced to 2 M (final volume of digest 80 µl) by the addition of 50 µl distilled water. Trypsin (2·5 mg ml1; Roche) was added in a 1 : 25 ratio to the CAMP factor 1 protein (w/w) and the mixture was incubated at 37 °C for 24 h. Digestion was stopped by freezing the sample at 20 °C. Purified antigen and its fragments were subjected to SDS-PAGE and electroblotted onto PVDF membrane (Bio-Rad). The bands were stained with Coomassie brilliant blue, excised and sequenced by Edman chemistry at the Babraham Institute (Cambridge, UK).
PCR amplification and sequencing.
PCR was used to detect the five CAMP factor homologue genes in a selection of P. acnes strains. CAMP factor genes were amplified using primers directed to downstream and upstream flanking sequences of each ORF (based on the P. acnes NCTC 737 genome sequence), thus facilitating accurate sequence determination of the 5' and 3' ends of each ORF. Preparation of bacterial genomic DNA and PCR amplifications were carried out essentially as described previously (McDowell et al., 2005). PCR samples contained 1x PCR buffer, 200 µM of each dNTP (Amersham Pharmacia Biotech), 200 µM of each appropriate CAMP factor oligonucleotide primer (Table 1
), 1·5 mM MgCl2, 1·25 U Platinum Taq DNA polymerase (Invitrogen Life Technologies) and 2·5 µl bacterial lysate, in a total volume of 25 µl. Samples were initially heated at 95 °C for 3 min, followed by 35 cycles of 1 min at 95 °C, 30 s at the appropriate annealing temperature (Table 1
) and 1 min at 72 °C. The PCR was completed with a final extension step at 72 °C for 10 min. A negative water control was included in all experiments. All PCR products were analysed as described before (McDowell et al., 2005
). Sequencing reactions were performed using ABI PRISM Ready Reaction Terminator cycle sequencing kits (Perkin Elmer Applied Biosystems) according to the manufacturer's instructions. Samples were analysed on an ABI PRISM 3100 DNA sequencer (Perkin Elmer Applied Biosystems).
|
![]() |
RESULTS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
|
|
|
|
|
|
Differences in CAMP factor protein expression between P. acnes types I and II
Expression of the five CAMP factor proteins by type I and II isolates was investigated by immunoblotting with rabbit polyclonal antisera raised against recombinant forms of each NCTC 737 CAMP factor protein, as well as a mouse mAb specific for CAMP factor 1. Representative immunoblots of NCTC 737 (type IA) and the prosthetic hip joint isolate SG2 (type II) are presented in Fig. 3. Labelled bands were observed in the correct region for the predicted molecular mass of the proteins, minus the signal sequence. Bands of lower molecular mass than that of the predicted secreted protein were sometimes observed and are believed to relate to degradation of a predicted labile N-terminal region. Isolates of P. acnes type II were found to produce large amounts of CAMP factor 1 compared with type IA strains. A corresponding abundant protein band was also observed on silver-stained SDS-PAGE gels of P. acnes type II, but was absent in type IA isolates (Fig. 4
) and NCTC 10390 (type II; data not shown). Larger quantities of CAMP 2, however, were detectable in type IA isolates compared with type II by immunoblotting, although levels of the protein were still considerably less than CAMP factor 1 production (Fig. 3
). Analysis of strains of P. acnes type IB by immunoblotting and silver staining of SDS-PAGE gels revealed a pattern of CAMP factor expression similar to that of type II organisms, with the production of large amounts of CAMP factor 1 and reduced expression of CAMP factor 2 compared with type IA strains (data not shown). Nucleotide sequences immediately upstream of the CAMP genes were compared to determine whether sequence differences in these regions could be influencing expression. Analysis revealed conservation of putative core ShineDalgarno sequences amongst the different P. acnes types for CAMP factors 1, 2, 3 and 5, but one base difference in the CAMP factor 1 ShineDalgarno sequence of NCTC 10390 was observed. The upstream sequences of CAMP factor 4 were more variable. The CAMP factor 4 gene for all isolates examined had a GTG start codon, whereas the start codon for all other CAMP factors was ATG (Fig. 5
).
|
|
|
Immunofluorescence labelling of CAMP factor 1 on whole cells of P. acnes
IFM with mAb QUBPa4 indicated that the CAMP factor 1 protein was both cell-associated and secreted (Fig. 6a). Mouse mAbs of the same isotype as QUBPa4, specific for cell-surface components of P. acnes I and II, respectively, did not label extracellular material by IFM (Fig. 6b, c
). A centrifugation wash in PBS of bacteria harvested from agar plates was sufficient to remove most of the CAMP factor 1 protein (Fig. 6d, e
). In addition, we also found that the protein could be obtained from broth culture after 50-fold concentration by ethanol precipitation. P. acnes type II strain NCTC 10390, which did not react with QUBPa4 by immunoblotting, was also non-reactive by IFM. IFM revealed no reactivity of QUBPa4 with P. granulosum, P. acidipropionici, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus agalactiae (data not shown). Although A. israelii and A. naeslundii showed no reaction with QUBPa4 by IFM, reactivity was observed after SDS-PAGE and immunoblotting (data not shown).
|
![]() |
DISCUSSION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Analysis of CAMP factor protein expression by immunoblotting and silver staining of SDS-PAGE gels revealed an abundance of CAMP factor 1 production by type II and type IB isolates, but not IA organisms. The type II strain NCTC 10390, however, was an exception, as abundant CAMP factor 1 protein was not detected. As the genes for all five CAMP factors are present in all three P. acnes groups, observed differences reflected different levels of expression rather than missing genes. One factor amongst many that could influence expression levels is the interaction between a ShineDalgarno ribosome-binding site and 16S rRNA. Strong ShineDalgarno sequences (e.g. GGAG, GAGG or AGGA) are associated with genes that are predicted to be highly expressed (Karlin & Mrazek, 2000). Interestingly, we identified a base difference in the putative ShineDalgarno sequence associated with the CAMP factor 1 gene of NCTC 10390, a type II strain that lacks abundant CAMP factor 1 production and is not reactive with our specific mAb by IFM. Whether or not this reduces the efficiency of interaction with the 16S ribosomal subunit, and therefore the level of expression of the protein, remains to be determined. The observation that NCTC 10390 differs from other type II organisms with respect to CAMP factor 1 production indicates that it is not the most appropriate representative strain of P. acnes type II.
Immunoblotting also revealed that type IA isolates express greater quantities of CAMP factor 2 compared with type II and type IB isolates; however, neither this nor the other CAMP factors were produced in quantity by IA strains, as the abundant protein band was not detectable by SDS-PAGE and silver staining. The putative ShineDalgarno sequences of CAMP factors 1 and 2 are conserved for all three phylogenetic groups; therefore, this cannot explain the differences in expression. No striking differences were observed with respect to the expression of CAMP factor proteins 3, 4 and 5, although CAMP factor 4 reacted only weakly in immunoblotting experiments with type IA and II isolates. The putative ShineDalgarno sequences upstream of the CAMP factor 4 genes were more varied amongst the three phylogenetic groupings, but comparison with the ShineDalgarno sequences of the other CAMP genes did not reveal any clear relationship that could explain the different expression levels. CAMP factor 4 does, however, have a GTG start codon, which is reported to be a weaker translational initiator than ATG (Ringquist et al., 1992).
All of the CAMP factor sequences contain a putative signal sequence cleavage site (Table 2) and molecular mass comparison of the proteins by SDS-PAGE and immunoblotting was in keeping with the loss of this signal sequence. IFM analysis and detection in ethanol-precipitated supernatant from broth culture confirmed that the CAMP factor 1 protein was secreted, although it was also detected on the surface of the P. acnes cells. Studies with Streptococcus agalactiae similarly detected CAMP factor protein in the external milieu, as well as on the cell surface (Jurgens et al., 1987
). None of the CAMP factor homologues from P. acnes or Streptococcus agalactiae contain a C-terminal Leu-Pro-X-Thr-Gly (LPXTG) motif, although 25 genes encoding other proteins with an LPXTG motif have been described in the genome of P. acnes strain KPA171202 (Bruggemann et al., 2004
).
Despite our observations of differential expression of the five CAMP factor homologues amongst P. acnes types IA, IB and II, all isolates from both groups were positive for the co-haemolytic phenotype. The P. acnes co-haemolytic reaction is therefore likely to be mediated by more than one CAMP factor protein. We are currently addressing the relationship between individual CAMP factors and the co-haemolytic phenotype. In our studies, some sequence identity between the P. acnes CAMP factor 1 and 3 proteins and Staphylococcus aureus protein A was demonstrated within the Fc-binding region, suggesting they may have immunoglobulin-binding activity. Interestingly, the percentage identities were greater than those of the Streptococcus agalactiae CAMP factor, which has been shown to bind IgG (Jurgens et al., 1987). It may be that the multiple P. acnes CAMP factors have arisen from divergence of a replicated common ancestral gene and now have divergent functions.
In addition to the P. acnes isolates studied, A. israelii and A. naeslundii produced a co-haemolytic reaction whereas P. granulosum did not. It would be interesting to determine whether this difference reflects the relative pathogenic potential of these organisms. The positive reaction between purified CAMP factor 1 protein and human sera obtained from patients with acne, as well as those undergoing primary or revision hip arthroplasty, indicates that the protein is expressed by P. acnes during human colonization. Whether its production relates to virulence remains to be determined, as the serum samples used were from a single time point and therefore give no indication of rising titre.
In conclusion, we have identified five genes with sequence identity to the co-haemolytic CAMP factor of Streptococcus agalactiae in strains of P. acnes types IA, IB and II. Differential protein expression of the CAMP factors amongst the various P. acnes phylogenetic groupings was observed; in particular, the extracellular and cell-associated CAMP factor 1 protein was produced in striking abundance by type IB and type II isolates. The observation of differential expression of putative virulence determinants amongst the various P. acnes types will have important consequences. In particular, it will impact on our interpretation of previously published virulence data that have been based on the study of only one isolate type, such as NCTC 737, which has often been used as a model organism for studies of P. acnes virulence (Roszkowski et al., 1980; Webster et al., 1985
). More generally, such data, in combination with the recent demonstration that P. acnes is genetically heterogeneous, will serve to challenge our current understanding of the virulence and pathogenic potential of clinical isolates of P. acnes.
![]() |
ACKNOWLEDGEMENTS |
---|
![]() |
REFERENCES |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Aldave, A. M., Stein, J. D., Deramo, V. A., Shah, G. K., Fischer, D. H. & Maguire, J. I. (1999). Treatment strategies for postoperative Propionibacterium acnes endophthalmitis. Ophthalmology 106, 23952401.[CrossRef][Medline]
Bernheimer, A. W., Linder, A. & Avigad, S. A. (1979). Nature and mechanism of action of the CAMP protein of group B streptococci. Infect Immun 23, 838844.[Medline]
Brook, I. & Frazier, E. H. (1991). Infections caused by Propionibacterium species. Rev Infect Dis 13, 819822.[Medline]
Brown, J., Farnsworth, R., Wannamaker, L. W. & Johnson, D. W. (1974). CAMP factor of group B streptococci: production, assay, and neutralization by sera from immunized rabbits and experimentally infected cows. Infect Immun 9, 377383.[Medline]
Bruggemann, H., Henne, A., Hoster, F., Liesegang, H., Wiezer, A., Strittmatter, A., Hujer, S., Durre, P. & Gottschalk, G. (2004). The complete genome sequence of Propionibacterium acnes, a commensal of human skin. Science 305, 671673.
Choudhury, T. K. (1978). Synergistic lysis of erythrocytes by Propionibacterium acnes. J Clin Microbiol 8, 238241.[Medline]
Christie, R., Atkins, N. E. & Munch-Petersen, E. (1944). A note on a lytic phenomenon shown by group B streptococci. Aust J Exp Biol Med Sci 22, 197200.
Clark, W. L., Kaiser, P. K., Flynn, H. W., Jr, Belfort, A., Miller, D. & Meisler, D. M. (1999). Treatment strategies and visual acuity outcomes in chronic postoperative Propionibacterium acnes endophthalmitis. Ophthalmology 106, 16651670.[CrossRef][Medline]
Debelian, G. J., Olsen, I. & Tronstad, L. (1992). Profiling of Propionibacterium acnes recovered from root canal and blood during and after endodontic treatment. Endod Dent Traumatol 8, 248254.[Medline]
Eady, E. A. & Ingham, E. (1994). Propionibacterium acnes friend or foe? Rev Med Microbiol 5, 163173.
Figura, N. & Guglielmetti, P. (1987). Differentiation of motile and mesophilic Aeromonas strains into species by testing for a CAMP-like factor. J Clin Microbiol 25, 13411342.[Medline]
Fraser, G. (1962). The hemolysis of animal erythrocytes by Pasteurella haemolytica produced in conjunction with certain staphylococcal toxins. Res Vet Sci 3, 104110.
Frey, J., Perrin, J. & Nicolet, J. (1989). Cloning and expression of a cohemolysin, the CAMP factor of Actinobacillus pleuropneumoniae. Infect Immun 57, 20502056.[Medline]
Funke, G., von Graevenitz, A., Clarridge, J. E., III & Bernard, K. A. (1997). Clinical microbiology of coryneform bacteria. Clin Microbiol Rev 10, 125159.[Abstract]
Glaser, P., Rusniok, C., Buchrieser, C. & 9 other authors (2002). Genome sequence of Streptococcus agalactiae, a pathogen causing invasive neonatal disease. Mol Microbiol 45, 14991513.[CrossRef][Medline]
Harlow, E. & Lane, D. (1988). Antibodies: a Laboratory Manual. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory.
Jiang, M., Babiuk, L. A. & Potter, A. A. (1996). Cloning, sequencing and expression of the CAMP factor gene of Streptococcus uberis. Microb Pathog 20, 297307.[CrossRef][Medline]
Johnson, J. L. & Cummins, C. S. (1972). Cell wall composition and deoxyribonucleic acid similarities among anaerobic coryneforms, classical propionibacteria, and strains of Arachnia propionica. J Bacteriol 109, 10471066.[Medline]
Jurgens, D., Shalaby, F. Y. Y. I. & Fehrenbach, F. J. (1985). Purification and characterization of CAMP-factor from Streptococcus agalactiae by hydrophobic interaction chromatography and chromatofocusing. J Chromatogr 348, 363370.[CrossRef][Medline]
Jurgens, D., Sterzik, B. & Fehrenbach, F. J. (1987). Unspecific binding of group B streptococcal cocytolysin (CAMP factor) to immunoglobulins and its possible role in pathogenicity. J Exp Med 165, 720732.
Karlin, S. & Mrazek, J. (2000). Predicted highly expressed genes of diverse prokaryotic genomes. J Bacteriol 182, 52385250.
Kohler, W. (1988). CAMP-like phenomena of vibrios. Zentralbl Bakteriol Mikrobiol Hyg A 270, 3540.[Medline]
Laemmli, U. K. (1970). Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227, 680685.[Medline]
Lang, S. & Palmer, M. (2003). Characterization of Streptococcus agalactiae CAMP factor as a pore-forming toxin. J Biol Chem 278, 3816738173.
Le Goff, A., Bunetel, L., Mouton, C. & Bonnaure-Mallet, M. (1997). Evaluation of root canal bacteria and their antimicrobial susceptibility in teeth with necrotic pulp. Oral Microbiol Immunol 12, 318322.[Medline]
Leyden, J. J., McGinley, K. J. & Vowels, B. (1998). Propionibacterium acnes colonization in acne and nonacne. Dermatology 196, 5558.[CrossRef][Medline]
McDowell, A., Valanne, S., Ramage, G. & 8 other authors (2005). Propionibacterium acnes types I and II represent phylogenetically distinct groups. J Clin Microbiol 43, 326334.
McGinley, K. J., Webster, G. F. & Leyden, J. J. (1978). Regional variations of cutaneous propionibacteria. Appl Environ Microbiol 35, 6266.[Medline]
Patrick, S. & Lutton, D. A. (1990). Outer membrane proteins of Bacteroides fragilis grown in vivo. FEMS Microbiol Lett 59, 14.[CrossRef][Medline]
Patrick, S., Stewart, L. D., Damani, N., Wilson, K. G., Lutton, D. A., Larkin, M. J., Poxton, I. & Brown, R. (1995). Immunological detection of Bacteroides fragilis in clinical samples. J Med Microbiol 43, 99109.[Abstract]
Ringquist, S., Shinedling, S., Barrick, D., Green, L., Binkley, J., Stormo, G. D. & Gold, L. (1992). Translation initiation in Escherichia coli: sequences within the ribosome-binding site. Mol Microbiol 6, 12191229.[Medline]
Roszkowski, W., Szmigielski, S., Ko, H. L., Janiak, M., Wrembel, J. K., Pulverer, G. & Jeljaszewicz, J. (1980). Effect of three strains of propionibacteria (P. granulosum, P. avidum, P. acnes) and cell-wall preparations on lymphocytes and macrophages. Zentralbl Bakteriol A 246, 393404.[Medline]
Ruhlmann, J., Wittmann-Liebold, B., Jurgens, D. & Fehrenbach, F. J. (1988). Complete amino acid sequence of protein B. FEBS Lett 235, 262266.[CrossRef][Medline]
Schaeverbeke, T., Lequen, L., de Barbeyrac, B., Labbe, L., Bebear, C. M., Morrier, Y., Bannwarth, B., Bebear, C. & Dehais, J. (1998). Propionibacterium acnes isolated from synovial tissue and fluid in a patient with oligoarthritis associated with acne and pustulosis. Arthritis Rheum 41, 18891893.[CrossRef][Medline]
Skalka, B., Smola, J. & Pillich, J. (1980). Comparison of some properties of the CAMP-factor from Streptococcus agalactiae with the haemolytically latent active exosubstance from Streptococcus uberis. Zentralbl Veterinarmed B 27, 559566.[Medline]
Soedermanto, I. & Lammler, C. (1996). Comparative studies on streptococci of serological group G isolated from various origins. Zentralbl Veterinarmed B 43, 513523.[Medline]
Tancrede, C. (1992). Role of human microflora in health and disease. Eur J Clin Microbiol Infect Dis 11, 10121015.[Medline]
Tasaka, S., Ishizaka, A., Sayama, K. & 9 other authors (1996). Heat-killed Corynebacterium parvum enhances endotoxin lung injury with increased TNF production in guinea pigs. Am J Respir Crit Care Med 153, 10471055.[Abstract]
Thompson, J. D., Higgins, D. G. & Gibson, T. J. (1994). CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. Nucleic Acids Res 22, 46734680.[Abstract]
Tunney, M. M., Patrick, S., Gorman, S. P., Nixon, J. R., Anderson, N., Davis, R. I., Hanna, D. & Ramage, G. (1998). Improved detection of infection in hip replacements. A currently underestimated problem. J Bone Joint Surg Br 80, 568572.[CrossRef][Medline]
Tunney, M. M., Patrick, S., Curran, M. D., Ramage, G., Anderson, N., Davis, R. I., Gorman, S. P. & Nixon, J. R. (1999a). Detection of prosthetic joint biofilm infection using immunological and molecular techniques. Methods Enzymol 310, 566576.[Medline]
Tunney, M. M., Patrick, S., Curran, M. D., Ramage, G., Hanna, D., Nixon, J. R., Gorman, S. P., Davis, R. I. & Anderson, N. (1999b). Detection of prosthetic hip infection at revision arthroplasty by immunofluorescence microscopy and PCR amplification of the bacterial 16S rRNA gene. J Clin Microbiol 37, 32813290.
Webster, G. F., Leyden, J. J., Musson, R. A. & Douglas, S. D. (1985). Susceptibility of Propionibacterium acnes to killing and degradation by human neutrophils and monocytes in vitro. Infect Immun 49, 116121.[Medline]
Received 25 November 2004;
revised 11 February 2005;
accepted 16 February 2005.
HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
INT J SYST EVOL MICROBIOL | MICROBIOLOGY | J GEN VIROL |
J MED MICROBIOL | ALL SGM JOURNALS |