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Friedrich Götz - One of the best experts on this subject based on the ideXlab platform.

  • Epidermin and gallidermin: Staphylococcal lantibiotics.
    International journal of medical microbiology : IJMM, 2013
    Co-Authors: Friedrich Götz, Silvana Perconti, Peter Popella, Rolf G. Werner, Martin Schlag
    Abstract:

    The Staphylococcus epidermidis derived Epidermin was the first lantibiotic that has been shown to be ribosomally synthesized and posttranslationally modified. Together with gallidermin, produced by Staphylococcus gallinarum, they belong to the large class of cationic antimicrobial peptides (CAMPs) that act against a broad spectrum of Gram-positive bacteria. Here we describe the genetic organization, biosynthesis and modification, excretion, extracellular activation of the modified pre-peptide by proteolytic processing, self-protection of the producer, gene regulation, structure, and the mode of action of gallidermin and Epidermin. We also address mechanisms of bacterial tolerance to these lantibiotics and other CAMPs. Particularly gallidermin has a high potential for therapeutic application, as it is active against methicillin-resistant Staphylococcus aureus strains (MRSA) and as it is able to prevent biofilm formation at sublethal concentrations.

  • Control of antimicrobial peptide synthesis by the agr quorum sensing system in Staphylococcus epidermidis: activity of the lantibiotic Epidermin is regulated at the level of precursor peptide processing.
    Peptides, 2003
    Co-Authors: Stefanie Kies, Cuong Vuong, Matthias Hille, Andreas Peschel, Cornelia Meyer, Friedrich Götz, Michael Otto
    Abstract:

    The accessory gene regulator (agr) quorum sensing system in staphylococci is responsible for the regulation of surface proteins and exoproteins, including many virulence factors in the pathogenic species Staphylococcus aureus and S. epidermidis. Strain S. epidermidis Tu3298 produces the lantibiotic Epidermin. An isogenic agr deletion mutant of this strain showed a strong reduction of Epidermin production. Detailed analysis of the impact of agr on Epidermin biosynthesis revealed that agr does not interfere with the transcription of Epidermin biosynthetic genes, but controls the extracellular processing of the N-terminal leader peptide by the EpiP protease.

  • Producer self-protection against the lantibiotic Epidermin by the ABC transporter EpiFEG of Staphylococcus epidermidis Tü3298
    FEMS microbiology letters, 1998
    Co-Authors: Michael Otto, Andreas Peschel, Friedrich Götz
    Abstract:

    Self-protection of the Epidermin-producing strain Staphylococcus epidermidis Tu3298 against the pore-forming lantibiotic Epidermin is mediated by an ABC transporter composed of the EpiF, EpiE, and EpiG proteins. We developed a sensitive assay based on HPLC analysis to investigate the capacity of the EpiFEG transporter to release Epidermin and analogues from the cell surface to the external fluid. Our results indicate that the EpiFEG transporter works by expelling the lantibiotic from the cytoplasmic membrane into the surrounding medium. Analysis of transporter efficacy using nisin and gallidermin derivatives as substrates revealed a high substrate specificity. Furthermore, we showed that the activity of the gallidermin derivative L6G is enhanced by the presence of EpiE.

  • Secretion of the lantibiotics Epidermin and gallidermin: sequence analysis of the genes gdmT and gdmH, their influence on Epidermin production and their regulation by EpiQ.
    Molecular & general genetics : MGG, 1997
    Co-Authors: Andreas Peschel, Matthias Hille, Norbert Schnell, K. D. Entian, Friedrich Götz
    Abstract:

    The closely related lantibiotics Epidermin and gallidermin are produced by Staphylococcus epidermidis Tu3298 and S. gallinarum Tu3928, respectively. The Epidermin biosynthetic genes involved in maturation, regulation, and immunity have been identified previously. How Epidermin or gallidermin is secreted, however, has remained unclear. Here, we characterize two additional genes, epiH and epiT, as well as the homologous gallidermin genes gdmH and gdmT. EpiT and GdmT are similar to one-component ABC transporters that are involved in the secretion of proteins or peptides. EpiH and GdmH are hydrophobic proteins without conspicuous similarities to other proteins. Comparison of the gene sequences revealed that epiT is incomplete, having an internal deletion that causes a frame shift and a second deletion at the 3′-end, while gdmT is intact. Introduction of epiT and epiH into the heterologous host S. carnosus (pTepi14) bearing the maturation and regulation genes had no significant effect on the rather low level of Epidermin production. The presence of the homologous gdmT and gdmH, however, resulted in a strong increase (seven- to tenfold) in the production level, which is very likely to be due to increased efficiency of Epidermin secretion. Both gdmT and gdmH were necessary for this effect, indicating that the two gene products cooperate in some way. In the Epidermin-producing wild-type strain Tu3298, which contains epiH and the disrupted epiT, the addition of gdmT alone led to a two-fold increase in Epidermin production. Both gdmT and gdmH and the corresponding epi genes were activated by the transcriptional regulator EpiQ; this is in accordance with the presence of putative EpiQ operator sites in the promoter regions.

  • Serine Protease EpiP from Staphylococcus epidermidis Catalyzes the Processing of the Epidermin Precursor Peptide
    1995
    Co-Authors: Friedrich Götz, F Götz, S Geissler, T Kupke, J. Bacteriol, Thomas Kupke
    Abstract:

    of the Epidermin precursor peptide

Andreas Peschel - One of the best experts on this subject based on the ideXlab platform.

  • Control of antimicrobial peptide synthesis by the agr quorum sensing system in Staphylococcus epidermidis: activity of the lantibiotic Epidermin is regulated at the level of precursor peptide processing.
    Peptides, 2003
    Co-Authors: Stefanie Kies, Cuong Vuong, Matthias Hille, Andreas Peschel, Cornelia Meyer, Friedrich Götz, Michael Otto
    Abstract:

    The accessory gene regulator (agr) quorum sensing system in staphylococci is responsible for the regulation of surface proteins and exoproteins, including many virulence factors in the pathogenic species Staphylococcus aureus and S. epidermidis. Strain S. epidermidis Tu3298 produces the lantibiotic Epidermin. An isogenic agr deletion mutant of this strain showed a strong reduction of Epidermin production. Detailed analysis of the impact of agr on Epidermin biosynthesis revealed that agr does not interfere with the transcription of Epidermin biosynthetic genes, but controls the extracellular processing of the N-terminal leader peptide by the EpiP protease.

  • Producer self-protection against the lantibiotic Epidermin by the ABC transporter EpiFEG of Staphylococcus epidermidis Tü3298
    FEMS microbiology letters, 1998
    Co-Authors: Michael Otto, Andreas Peschel, Friedrich Götz
    Abstract:

    Self-protection of the Epidermin-producing strain Staphylococcus epidermidis Tu3298 against the pore-forming lantibiotic Epidermin is mediated by an ABC transporter composed of the EpiF, EpiE, and EpiG proteins. We developed a sensitive assay based on HPLC analysis to investigate the capacity of the EpiFEG transporter to release Epidermin and analogues from the cell surface to the external fluid. Our results indicate that the EpiFEG transporter works by expelling the lantibiotic from the cytoplasmic membrane into the surrounding medium. Analysis of transporter efficacy using nisin and gallidermin derivatives as substrates revealed a high substrate specificity. Furthermore, we showed that the activity of the gallidermin derivative L6G is enhanced by the presence of EpiE.

  • ABC transporter EpiFEG of Staphylococcus epidermidis Tii3298
    1998
    Co-Authors: Michael Otto, Andreas Peschel
    Abstract:

    Self-protection of the Epidermin-producing strain Staphylococcus epidermidis Tii3298 against the pore-forming lantibiotic Epidermin is mediated by an ABC transporter composed of the EpiF, EpiE, and EpiG proteins. We developed a sensitive assay based on HPLC analysis to investigate the capacity of the EpiFEG transporter to release Epidermin and analogues from the cell surface to the external fluid. Our results indicate that the EpiFEG transporter works by expelling the lantibiotic from the cytoplasmic membrane into the surrounding medium. Analysis of transporter efficacy using nisin and gallidertnin derivatives as substrates revealed a high substrate specificity. Furthermore, we showed that the activity of the gallidermin derivative L6G is enhanced by the presence of EpiE. 0 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

  • Secretion of the lantibiotics Epidermin and gallidermin: sequence analysis of the genes gdmT and gdmH, their influence on Epidermin production and their regulation by EpiQ.
    Molecular & general genetics : MGG, 1997
    Co-Authors: Andreas Peschel, Matthias Hille, Norbert Schnell, K. D. Entian, Friedrich Götz
    Abstract:

    The closely related lantibiotics Epidermin and gallidermin are produced by Staphylococcus epidermidis Tu3298 and S. gallinarum Tu3928, respectively. The Epidermin biosynthetic genes involved in maturation, regulation, and immunity have been identified previously. How Epidermin or gallidermin is secreted, however, has remained unclear. Here, we characterize two additional genes, epiH and epiT, as well as the homologous gallidermin genes gdmH and gdmT. EpiT and GdmT are similar to one-component ABC transporters that are involved in the secretion of proteins or peptides. EpiH and GdmH are hydrophobic proteins without conspicuous similarities to other proteins. Comparison of the gene sequences revealed that epiT is incomplete, having an internal deletion that causes a frame shift and a second deletion at the 3′-end, while gdmT is intact. Introduction of epiT and epiH into the heterologous host S. carnosus (pTepi14) bearing the maturation and regulation genes had no significant effect on the rather low level of Epidermin production. The presence of the homologous gdmT and gdmH, however, resulted in a strong increase (seven- to tenfold) in the production level, which is very likely to be due to increased efficiency of Epidermin secretion. Both gdmT and gdmH were necessary for this effect, indicating that the two gene products cooperate in some way. In the Epidermin-producing wild-type strain Tu3298, which contains epiH and the disrupted epiT, the addition of gdmT alone led to a two-fold increase in Epidermin production. Both gdmT and gdmH and the corresponding epi genes were activated by the transcriptional regulator EpiQ; this is in accordance with the presence of putative EpiQ operator sites in the promoter regions.

  • Analysis of the Staphylococcus epidermidis genes epiF, -E, and -G involved in Epidermin immunity.
    Journal of bacteriology, 1996
    Co-Authors: Andreas Peschel, F Götz
    Abstract:

    The lantibiotic Epidermin is produced by Staphylococcus epidermidis Tu3298. The known genes involved in Epidermin biosynthesis and regulation are organized as operons (epiABCD and epiQP) that are encoded on the 54-kb plasmid pTu32. Here we describe the characterization of a DNA region that mediates immunity and increased Epidermin production, located upstream of the structural gene epiA. The sequence of a 2.6-kb DNA fragment revealed three open reading frames, epiF, -E, and -G, which may form an operon. In the cloning host Staphylococcus carnosus, the three genes mediated an increased tolerance to Epidermin, and the highest level of immunity (sevenfold) was achieved with S. carnosus carrying epiFEG and epiQ. The promoter of the first gene, epiF, responded to the activator protein EpiQ and contained a palindromic sequence similar to the EpiQ binding site of the epiA promoter, which is also activated by EpiQ. Inactivation of epiF, -E, or -G resulted in the complete loss of the immunity phenotype. An Epidermin-sensitive S. epidermidis Tu3298 mutant was complemented by a DNA fragment containing all three genes. When the epiFEG genes were cloned together with plasmid pTepi14, containing the biosynthetic genes epiABCDQP, the level of Epidermin production was approximately fivefold higher. The proteins EpiF, -E, and -G are similar in deduced sequence and proposed structure to the components of various ABC transporter systems. EpiF is a hydrophilic protein with conserved ATP-binding sites, while EpiE and -G have six alternating hydrophobic regions and very likely constitute the integral membrane domains. When EpiF was overproduced in S. carnosus, it was at least partially associated with the cytoplasmic membrane. A potential mechanism for how EpiFEG mediates immunity is discussed.

Johannes Augustin - One of the best experts on this subject based on the ideXlab platform.

  • Regulation of Epidermin biosynthetic genes by EpiQ
    Molecular microbiology, 1993
    Co-Authors: Andreas Peschel, Johannes Augustin, Thomas Kupke, Stefan Stevanovic, Friedrich Götz
    Abstract:

    Summary We investigated the role of epiQ in the biosynthesis of the lantibiotic Epidermin. epiQ was essential for Epidermin production. It was shown that EpiQ controls Epidermin production by transcriptionally activating the epiA promoter, used for transcription of most of the Epidermin biosynthetic genes. Additional copies of epiQ increased Epidermin production in the Epidermin-producing wild-type strain Staphylococcus epidermidis Tu3298. The epiA promoter region was characterized by primer extension analysis. Two inverted repeats, putative operator sites for EpiQ binding, are located upstream of the −35 region and one is localized downstream of the-10 region. Crude protein extracts from S. epidermidis Tu3298 and epiQ expressing Escherichia coli cells led to gel mobility shifts of a DNA fragment bearing the inverted repeat which is located immediately upstream of the -35 region. DNA fragments bearing the other two inverted repeats were not shifted. The epiQ gene product could be detected by overexpression in the E. coli T7 system using antiserum raised against synthetic pep-tides of EpiQ. Furthermore, EpiQ, like other DNA-binding proteins, was shown to bind strongly to heparin sepharose.

  • Genetic analysis of Epidermin biosynthetic genes and Epidermin‐negative mutants of Staphylococcus epidermidis
    European journal of biochemistry, 1992
    Co-Authors: Johannes Augustin, Germar Dr Engelke, Ralf Rosenstein, Karl-dieter Entian, Wieland Bernd, Uschi Schneider, Schnell Norbert, Friedrich Götz
    Abstract:

    Epidermin is produced by Staphylococcus epidermidis Tu3298 which harbors the 54-kb plasmid, pTu32. The plasmid contains not only the Epidermin structural gene epiA, but also a flanking DNA region which is necessary for Epidermin biosynthesis. The DNA sequence of this region revealed, in addition to epiA, five additional open reading frames, epiB, C, D, Q and P [Schnell, N., Engelke, G., Augustin J., Rosenstein, R., Ungermann, V., Gotz, F. & Entian, K.-D. (1992) Eur. J. Biochem. 204, 57-68]. We isolated a number of stable mutants from strain Tu3298 which are unable to produce biologically active Epidermin. Complementation studies using the newly constructed staphylococcal plasmid vectors pT181mcs and pCU1 led to their classification as epiA, epiB, epiC or epiD mutants. Furthermore, evidence is presented that epiB lacks its own promoter and is co-transcribed from the epiA promoter. There is evidence that epiC and D possess their own promoters. Although epiQ and epiP mutants were not isolated, it could be shown by heterologous gene expression in S. carnosus and S. xylosus that the corresponding DNA region is involved in Epidermin biosynthesis. We can not exclude the possibility that, in addition to the four open reading frames, epiA, B, C, D, and the DNA region comprising epiQ and P, host-encoded functions are necessary for Epidermin production. Thus, the genetic information for Epidermin biosynthesis in S. carnosus and S. xylosus is located on an 8-kb DNA fragment of pTu32. A further characterization of the two epiA mutants revealed that in both mutants, the preEpidermin nucleotide sequence was changed. In one mutant, the mutation led to a substitution of Ser3 by Asn; in the other of Gly10 by Glu.

  • genetic analysis of Epidermin biosynthetic genes and Epidermin negative mutants of staphylococcus epidermidis
    FEBS Journal, 1992
    Co-Authors: Johannes Augustin, Ralf Rosenstein, Karl-dieter Entian, Wieland Bernd, Uschi Schneider, Schnell Norbert, Germar Engelke, Friedrich Götz
    Abstract:

    Epidermin is produced by Staphylococcus epidermidis Tu3298 which harbors the 54-kb plasmid, pTu32. The plasmid contains not only the Epidermin structural gene epiA, but also a flanking DNA region which is necessary for Epidermin biosynthesis. The DNA sequence of this region revealed, in addition to epiA, five additional open reading frames, epiB, C, D, Q and P [Schnell, N., Engelke, G., Augustin J., Rosenstein, R., Ungermann, V., Gotz, F. & Entian, K.-D. (1992) Eur. J. Biochem. 204, 57-68]. We isolated a number of stable mutants from strain Tu3298 which are unable to produce biologically active Epidermin. Complementation studies using the newly constructed staphylococcal plasmid vectors pT181mcs and pCU1 led to their classification as epiA, epiB, epiC or epiD mutants. Furthermore, evidence is presented that epiB lacks its own promoter and is co-transcribed from the epiA promoter. There is evidence that epiC and D possess their own promoters. Although epiQ and epiP mutants were not isolated, it could be shown by heterologous gene expression in S. carnosus and S. xylosus that the corresponding DNA region is involved in Epidermin biosynthesis. We can not exclude the possibility that, in addition to the four open reading frames, epiA, B, C, D, and the DNA region comprising epiQ and P, host-encoded functions are necessary for Epidermin production. Thus, the genetic information for Epidermin biosynthesis in S. carnosus and S. xylosus is located on an 8-kb DNA fragment of pTu32. A further characterization of the two epiA mutants revealed that in both mutants, the preEpidermin nucleotide sequence was changed. In one mutant, the mutation led to a substitution of Ser3 by Asn; in the other of Gly10 by Glu.

  • Analysis of genes involved in the biosynthesis of lantibiotic Epidermin.
    European journal of biochemistry, 1992
    Co-Authors: Norbert Schnell, Friedrich Götz, Johannes Augustin, Germar Dr Engelke, Ralf Rosenstein, V. Ungermann, Karl-dieter Entian
    Abstract:

    The structural gene of the lanthionine-containing peptide antibiotic Epidermin is located on a 54-kb plasmid of Staphylococcus epidermidis [Schnell et al. (1988) Nature 333, 276-278]. A 13.5-kb DNA region neighbouring the Epidermin structural gene (epiA) was subcloned and its sequencing revealed five additional open reading frames. Three of these reading frames, epiB, epiC and epiD shared no homology with previously described proteins stored in data bases. They were located 3' adjacent to epiA. Using epiB as a probe, a 5-kb mRNA was identified indicating that three or all four reading frames are transcribed as an operon. Additionally, a 0.3-kb mRNA specific for epiA was identified. Two open reading frames (epiP and epiQ) were located 3' to epiA, epiB, epiC and epiD, but in the reverse orientation. The epiQ gene product shows similarity to the positive regulatory factor PhoB. This might indicate a regulatory function of epiQ in Epidermin biosynthesis. The epiP gene product shows striking similarity to several serine proteases which makes epiP a likely candidate for processing the Epidermin prepeptide. Heterologous Epidermin synthesis in the non-producing organism Staphylococcus carnosus finally proved that these reading frames are necessary for Epidermin biosynthesis.

Karl-dieter Entian - One of the best experts on this subject based on the ideXlab platform.

  • Genetic analysis of Epidermin biosynthetic genes and Epidermin‐negative mutants of Staphylococcus epidermidis
    European journal of biochemistry, 1992
    Co-Authors: Johannes Augustin, Germar Dr Engelke, Ralf Rosenstein, Karl-dieter Entian, Wieland Bernd, Uschi Schneider, Schnell Norbert, Friedrich Götz
    Abstract:

    Epidermin is produced by Staphylococcus epidermidis Tu3298 which harbors the 54-kb plasmid, pTu32. The plasmid contains not only the Epidermin structural gene epiA, but also a flanking DNA region which is necessary for Epidermin biosynthesis. The DNA sequence of this region revealed, in addition to epiA, five additional open reading frames, epiB, C, D, Q and P [Schnell, N., Engelke, G., Augustin J., Rosenstein, R., Ungermann, V., Gotz, F. & Entian, K.-D. (1992) Eur. J. Biochem. 204, 57-68]. We isolated a number of stable mutants from strain Tu3298 which are unable to produce biologically active Epidermin. Complementation studies using the newly constructed staphylococcal plasmid vectors pT181mcs and pCU1 led to their classification as epiA, epiB, epiC or epiD mutants. Furthermore, evidence is presented that epiB lacks its own promoter and is co-transcribed from the epiA promoter. There is evidence that epiC and D possess their own promoters. Although epiQ and epiP mutants were not isolated, it could be shown by heterologous gene expression in S. carnosus and S. xylosus that the corresponding DNA region is involved in Epidermin biosynthesis. We can not exclude the possibility that, in addition to the four open reading frames, epiA, B, C, D, and the DNA region comprising epiQ and P, host-encoded functions are necessary for Epidermin production. Thus, the genetic information for Epidermin biosynthesis in S. carnosus and S. xylosus is located on an 8-kb DNA fragment of pTu32. A further characterization of the two epiA mutants revealed that in both mutants, the preEpidermin nucleotide sequence was changed. In one mutant, the mutation led to a substitution of Ser3 by Asn; in the other of Gly10 by Glu.

  • genetic analysis of Epidermin biosynthetic genes and Epidermin negative mutants of staphylococcus epidermidis
    FEBS Journal, 1992
    Co-Authors: Johannes Augustin, Ralf Rosenstein, Karl-dieter Entian, Wieland Bernd, Uschi Schneider, Schnell Norbert, Germar Engelke, Friedrich Götz
    Abstract:

    Epidermin is produced by Staphylococcus epidermidis Tu3298 which harbors the 54-kb plasmid, pTu32. The plasmid contains not only the Epidermin structural gene epiA, but also a flanking DNA region which is necessary for Epidermin biosynthesis. The DNA sequence of this region revealed, in addition to epiA, five additional open reading frames, epiB, C, D, Q and P [Schnell, N., Engelke, G., Augustin J., Rosenstein, R., Ungermann, V., Gotz, F. & Entian, K.-D. (1992) Eur. J. Biochem. 204, 57-68]. We isolated a number of stable mutants from strain Tu3298 which are unable to produce biologically active Epidermin. Complementation studies using the newly constructed staphylococcal plasmid vectors pT181mcs and pCU1 led to their classification as epiA, epiB, epiC or epiD mutants. Furthermore, evidence is presented that epiB lacks its own promoter and is co-transcribed from the epiA promoter. There is evidence that epiC and D possess their own promoters. Although epiQ and epiP mutants were not isolated, it could be shown by heterologous gene expression in S. carnosus and S. xylosus that the corresponding DNA region is involved in Epidermin biosynthesis. We can not exclude the possibility that, in addition to the four open reading frames, epiA, B, C, D, and the DNA region comprising epiQ and P, host-encoded functions are necessary for Epidermin production. Thus, the genetic information for Epidermin biosynthesis in S. carnosus and S. xylosus is located on an 8-kb DNA fragment of pTu32. A further characterization of the two epiA mutants revealed that in both mutants, the preEpidermin nucleotide sequence was changed. In one mutant, the mutation led to a substitution of Ser3 by Asn; in the other of Gly10 by Glu.

  • Analysis of genes involved in the biosynthesis of lantibiotic Epidermin.
    European journal of biochemistry, 1992
    Co-Authors: Norbert Schnell, Friedrich Götz, Johannes Augustin, Germar Dr Engelke, Ralf Rosenstein, V. Ungermann, Karl-dieter Entian
    Abstract:

    The structural gene of the lanthionine-containing peptide antibiotic Epidermin is located on a 54-kb plasmid of Staphylococcus epidermidis [Schnell et al. (1988) Nature 333, 276-278]. A 13.5-kb DNA region neighbouring the Epidermin structural gene (epiA) was subcloned and its sequencing revealed five additional open reading frames. Three of these reading frames, epiB, epiC and epiD shared no homology with previously described proteins stored in data bases. They were located 3' adjacent to epiA. Using epiB as a probe, a 5-kb mRNA was identified indicating that three or all four reading frames are transcribed as an operon. Additionally, a 0.3-kb mRNA specific for epiA was identified. Two open reading frames (epiP and epiQ) were located 3' to epiA, epiB, epiC and epiD, but in the reverse orientation. The epiQ gene product shows similarity to the positive regulatory factor PhoB. This might indicate a regulatory function of epiQ in Epidermin biosynthesis. The epiP gene product shows striking similarity to several serine proteases which makes epiP a likely candidate for processing the Epidermin prepeptide. Heterologous Epidermin synthesis in the non-producing organism Staphylococcus carnosus finally proved that these reading frames are necessary for Epidermin biosynthesis.

F Götz - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of the Staphylococcus epidermidis genes epiF, -E, and -G involved in Epidermin immunity.
    Journal of bacteriology, 1996
    Co-Authors: Andreas Peschel, F Götz
    Abstract:

    The lantibiotic Epidermin is produced by Staphylococcus epidermidis Tu3298. The known genes involved in Epidermin biosynthesis and regulation are organized as operons (epiABCD and epiQP) that are encoded on the 54-kb plasmid pTu32. Here we describe the characterization of a DNA region that mediates immunity and increased Epidermin production, located upstream of the structural gene epiA. The sequence of a 2.6-kb DNA fragment revealed three open reading frames, epiF, -E, and -G, which may form an operon. In the cloning host Staphylococcus carnosus, the three genes mediated an increased tolerance to Epidermin, and the highest level of immunity (sevenfold) was achieved with S. carnosus carrying epiFEG and epiQ. The promoter of the first gene, epiF, responded to the activator protein EpiQ and contained a palindromic sequence similar to the EpiQ binding site of the epiA promoter, which is also activated by EpiQ. Inactivation of epiF, -E, or -G resulted in the complete loss of the immunity phenotype. An Epidermin-sensitive S. epidermidis Tu3298 mutant was complemented by a DNA fragment containing all three genes. When the epiFEG genes were cloned together with plasmid pTepi14, containing the biosynthetic genes epiABCDQP, the level of Epidermin production was approximately fivefold higher. The proteins EpiF, -E, and -G are similar in deduced sequence and proposed structure to the components of various ABC transporter systems. EpiF is a hydrophilic protein with conserved ATP-binding sites, while EpiE and -G have six alternating hydrophobic regions and very likely constitute the integral membrane domains. When EpiF was overproduced in S. carnosus, it was at least partially associated with the cytoplasmic membrane. A potential mechanism for how EpiFEG mediates immunity is discussed.

  • Serine Protease EpiP from Staphylococcus epidermidis Catalyzes the Processing of the Epidermin Precursor Peptide
    1995
    Co-Authors: Friedrich Götz, F Götz, S Geissler, T Kupke, J. Bacteriol, Thomas Kupke
    Abstract:

    of the Epidermin precursor peptide