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Hans-georg Sahl - One of the best experts on this subject based on the ideXlab platform.
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Proteomic Response of Bacillus subtilis to Lantibiotics Reflects Differences in Interaction with the Cytoplasmic Membrane
2016Co-Authors: Hans-georg Sahl, Julia E. BAbstract:Mersacidin, gallidermin, and nisin are lantibiotics, antimicrobial peptides containing lanthionine. They show potent antibacte-rial activity. All three interfere with cell wall biosynthesis by binding lipid II, but they display different levels of interaction with the cytoplasmic membrane. On one end of the spectrum, Mersacidin interferes with cell wall biosynthesis by binding lipid II without integrating into bacterial membranes. On the other end of the spectrum, nisin readily integrates into membranes, where it forms large pores. It destroys the membrane potential and causes leakage of nutrients and ions. Gallidermin, in an intermedi-ate position, also readily integrates into membranes. However, pore formation occurs only in some bacteria and depends on membrane composition. In this study, we investigated the impact of nisin, gallidermin, andMersacidin on cell wall integrity, membrane pore formation, and membrane depolarization in Bacillus subtilis. The impact of the lantibiotics on the cell envelope was correlated to the proteomic response they elicit in B. subtilis. By drawing on a proteomic response library, including other envelope-targeting antibiotics such as bacitracin, vancomycin, gramicidin S, or valinomycin, YtrE could be identified as the most reliable marker protein for interfering with membrane-bound steps of cell wall biosynthesis. NadE and PspA were identified as markers for antibiotics interacting with the cytoplasmic membrane. Over the last decades, bacteria have demonstrated their im-pressive ability to adapt to changing environmental condi-tions by rapidly developing and accumulating antibiotic resis-tances. Helped by an extensive use of antibiotics in health care an
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Pseudomycoicidin, a Class II Lantibiotic from Bacillus pseudomycoides
Applied and environmental microbiology, 2015Co-Authors: Shradha Basi-chipalu, Hans-georg Sahl, Jasmin Dischinger, Christiane Szekat, Michaele Josten, Annegret Zweynert, Gabriele BierbaumAbstract:Lantibiotics are ribosomally synthesized antimicrobial peptides with substantial posttranslational modifications. They are characterized by the unique amino acids lanthionine and methyllanthionine, which are introduced by dehydration of Ser/Thr residues and linkage of the resulting dehydrated amino acids with Cys residues. BLAST searches using the Mersacidin biosynthetic enzyme (MrsM) in the NCBI database revealed a new class II lantibiotic gene cluster in Bacillus pseudomycoides DSM 12442. Production of an antimicrobial substance with activity against Gram-positive bacteria was detectable in a cell wash extract of this strain. The substance was partially purified, and mass spectrometric analysis predicted a peptide of 2,786 Da in the active fraction. In order to characterize the putative lantibiotic further, heterologous expression of the predicted biosynthetic genes was performed in Escherichia coli. Coexpression of the prepeptide (PseA) along with the corresponding modification enzyme (PseM) resulted in the production of a modified peptide with the corresponding mass, carrying four out of eight possible dehydrations and supporting the presence of four thioether and one disulfide bridge. After the proteolytic removal of the leader, the core peptide exhibited antimicrobial activity. In conclusion, pseudomycoicidin is a novel lantibiotic with antimicrobial activity that was heterologously produced in E. coli.
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The (partial) Mersacidin biosynthesis gene clusters of the Mersacidin producer B. sp. HIL Y-85,54728, B. amyloliquefaciens FZB42 and its derivatives.
2013Co-Authors: Anna Maria Herzner, Hans-georg Sahl, Jasmin Dischinger, Christiane Szekat, Michaele Josten, Stephanie Schmitz, Anja Yakéléba, Ricarda Reinartz, Andrea Jansen, Jörn PielAbstract:The Mersacidin gene cluster of the original producer strain B. sp. HIL Y-85,54728 (A) consists of the immunity genes mrsFGE (green colors), the structural gene mrsA (light blue), the modification enzymes mrsD and mrsM (dark blue colors), the exporter containing a protease domain mrsT (purple) and the regulatory genes mrsR1, mrsR2 and mrsK2 (yellow and orange colors). The genome of B. amyloliquefaciens FZB42 (B) harbors a partial Mersacidin gene cluster consisting of the immunity genes mrsFGE and the regulatory genes mrsK2 and mrsR2. The genes are found at the same site as in the original producer strain, i. e. between ycdJ and fbaB. In the mutant strain B. amyloliquefaciens mrs1 (C), a partial completion of the Mersacidin gene cluster was reached by competence transformation using genomic DNA of a Mersacidin deletion mutant (B. sp. HIL Y-85,54728 Rec1). An erythromycin resistance (ermB) cassette substituting mrsA served as selection marker. mrsR1 is most probably not transcribed in this mutant because of a polar effect. The completion of the Mersacidin gene cluster in B. amyloliquefaciens mrs1 pPAR1 (D) was achieved in trans by transformation with the plasmid pPAR1, carrying the structural gene mrsA and mrsR1, yielding B. amyloliquefaciens mrs1 pPAR1.
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MALDI-TOF mass spectra of pure Mersacidin and culture supernatants of B. amyloliquefaciens clones.
2013Co-Authors: Anna Maria Herzner, Hans-georg Sahl, Jasmin Dischinger, Christiane Szekat, Michaele Josten, Stephanie Schmitz, Anja Yakéléba, Ricarda Reinartz, Andrea Jansen, Jörn PielAbstract:Panel (A) shows pure Mersacidin (control). The spectra of culture supernatants of B. amyloliquefaciens FZB42 (B) as well as of B. amyloliquefaciens mrs1 (C), which harbor only a part of the Mersacidin gene cluster or miss the structural gene mrsA, respectively, show no Mersacidin production. In contrast, the culture supernatant of B. amyloliquefaciens mrs1 pPAR1 (D) is characterized by the presence of the typical Mersacidin-related mass signals [1826 Da: Mersacidin + H, 1848 Da: Mersacidin + Na and 1864 Da: Mersacidin + K] which demonstrate the production of Mersacidin by this strain.
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Amino acid alignments of two-peptide lantibiotics.
2013Co-Authors: Jasmin Dischinger, Hans-georg Sahl, Christiane Szekat, Michaele Josten, Gabriele BierbaumAbstract:(A) Amino acid sequence alignment of the LicA1 propeptide with the LanA1 propeptides of the two-peptide lantibiotics plantaricin (PlwA1, AAG02567), staphylococcin C55 (SacA1, BAB78438), lacticin 3147 (LtnA1, O87236), haloduracin (HalA1, BAB04173), BHT (BhtA1, AAZ76603) and Smb (SmbA1, BAD72777) and, for comparison, the propeptide of Mersacidin (MrsA, Z47559). Amino acid identities of the LanA1 propeptides are highlighted in green (100%), pink (75%) and blue (35%). The thioether bridging pattern represents that of the Halα and Plwα peptide. (B) Amino acid sequence alignment of the LicA2 propeptide with the Lanβ/LanA2 propeptides of the two-peptide lantibiotics plantaricin (PlwA2, AAG02566), staphylococcin C55 (SacA2, BAB78439), lacticin 3147 (LtnA2, O87237), haloduracin (HalA2, BAB04172), BHT (BhtA2, AAZ76602) and Smb (SmbA2, BAD72776). Amino acid identities are highlighted in green (100%), pink (75%) and blue (35%). The thioether bridging pattern represents that of the Halβ and Plwβ peptides.
Gabriele Bierbaum - One of the best experts on this subject based on the ideXlab platform.
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Pseudomycoicidin, a Class II Lantibiotic from Bacillus pseudomycoides
Applied and environmental microbiology, 2015Co-Authors: Shradha Basi-chipalu, Hans-georg Sahl, Jasmin Dischinger, Christiane Szekat, Michaele Josten, Annegret Zweynert, Gabriele BierbaumAbstract:Lantibiotics are ribosomally synthesized antimicrobial peptides with substantial posttranslational modifications. They are characterized by the unique amino acids lanthionine and methyllanthionine, which are introduced by dehydration of Ser/Thr residues and linkage of the resulting dehydrated amino acids with Cys residues. BLAST searches using the Mersacidin biosynthetic enzyme (MrsM) in the NCBI database revealed a new class II lantibiotic gene cluster in Bacillus pseudomycoides DSM 12442. Production of an antimicrobial substance with activity against Gram-positive bacteria was detectable in a cell wash extract of this strain. The substance was partially purified, and mass spectrometric analysis predicted a peptide of 2,786 Da in the active fraction. In order to characterize the putative lantibiotic further, heterologous expression of the predicted biosynthetic genes was performed in Escherichia coli. Coexpression of the prepeptide (PseA) along with the corresponding modification enzyme (PseM) resulted in the production of a modified peptide with the corresponding mass, carrying four out of eight possible dehydrations and supporting the presence of four thioether and one disulfide bridge. After the proteolytic removal of the leader, the core peptide exhibited antimicrobial activity. In conclusion, pseudomycoicidin is a novel lantibiotic with antimicrobial activity that was heterologously produced in E. coli.
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Amino acid alignments of two-peptide lantibiotics.
2013Co-Authors: Jasmin Dischinger, Hans-georg Sahl, Christiane Szekat, Michaele Josten, Gabriele BierbaumAbstract:(A) Amino acid sequence alignment of the LicA1 propeptide with the LanA1 propeptides of the two-peptide lantibiotics plantaricin (PlwA1, AAG02567), staphylococcin C55 (SacA1, BAB78438), lacticin 3147 (LtnA1, O87236), haloduracin (HalA1, BAB04173), BHT (BhtA1, AAZ76603) and Smb (SmbA1, BAD72777) and, for comparison, the propeptide of Mersacidin (MrsA, Z47559). Amino acid identities of the LanA1 propeptides are highlighted in green (100%), pink (75%) and blue (35%). The thioether bridging pattern represents that of the Halα and Plwα peptide. (B) Amino acid sequence alignment of the LicA2 propeptide with the Lanβ/LanA2 propeptides of the two-peptide lantibiotics plantaricin (PlwA2, AAG02566), staphylococcin C55 (SacA2, BAB78439), lacticin 3147 (LtnA2, O87237), haloduracin (HalA2, BAB04172), BHT (BhtA2, AAZ76602) and Smb (SmbA2, BAD72776). Amino acid identities are highlighted in green (100%), pink (75%) and blue (35%). The thioether bridging pattern represents that of the Halβ and Plwβ peptides.
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Dissecting Structural and Functional Diversity of the Lantibiotic Mersacidin
Chemistry & biology, 2009Co-Authors: Antony N. Appleyard, Gabriele Bierbaum, Shaila Choi, Daniel M. Read, Ann Lightfoot, Steven Boakes, Anja Hoffmann, Ian Chopra, Brian A.m. Rudd, Michael J. DawsonAbstract:Mersacidin is a tetracyclic lantibiotic with antibacterial activity against Gram-positive pathogens. To probe the specificity of the biosynthetic pathway of Mersacidin and obtain analogs with improved antibacterial activity, an efficient system for generating variants of this lantibiotic was developed. A saturation mutagenesis library of the residues of Mersacidin not involved in cycle formation was constructed and used to validate this system. Mersacidin analogs were obtained in good yield in approximately 35% of the cases, producing a collection of 82 new compounds. This system was also used for the production of deletion and insertion mutants of Mersacidin. The outcome of these studies suggests that this system can be extended to produce Mersacidin variants with multiple changes that will allow a full investigation of the potential use of modified Mersacidins as therapeutic agents.
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Native graS mutation supports the susceptibility of Staphylococcus aureus strain SG511 to antimicrobial peptides.
International journal of medical microbiology : IJMM, 2009Co-Authors: Peter Sass, Gabriele BierbaumAbstract:Staphylococcus aureus strain SG511-Berlin has been used as a standard strain for antimicrobial susceptibility testing and basic research since the first half of the last century. This study aimed at the identification of features of S. aureus SG511-Berlin that contribute to its high susceptibility to antimicrobial peptides (AMPs) in order to give insights into the mechanisms that S. aureus uses to counteract antimicrobials and to evaluate the role of S. aureus SG511-Berlin as a standard test strain. Comparative transcriptional profiling of S. aureus SG511-Berlin versus the more resistant S. aureus SA137/93A revealed a divergent regulation of the dltB, mprF, and vraFG genes, which are under the control of the two-component regulatory system (TCRS) GraRS. These gene transcripts showed significantly lower abundance in strain SG511-Berlin. Sequence analysis of graS in strain SG511-Berlin revealed a native nucleotide insertion that generates a stop codon at position 64 of the sensor histidine kinase GraS, thereby deleting the entire cytoplasmic part of the protein. Quantitative RT-PCR and determination of the whole-cell surface charge of graS complemented S. aureus SG511-Berlin directly linked its decreased dltB transcript level and the resulting increased negative cell surface charge to the nucleotide insertion in graS. Further MIC testings identified the GraRS TCRS as a resistance determinant to the lantibiotics Mersacidin, nisin, and Pep5. Due to these findings, the use of S. aureus SG511-Berlin for research purposes should be carefully considered, since this strain does not reflect the normal response of S. aureus against antibiotics.
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The lantibiotic Mersacidin is a strong inducer of the cell wall stress response of Staphylococcus aureus
BMC microbiology, 2008Co-Authors: Peter Sass, Hans-georg Sahl, Christiane Szekat, Andrea Jansen, Vera Sass, Gabriele BierbaumAbstract:Background The lantibiotic Mersacidin is an antimicrobial peptide of 20 amino acids that is ribosomally produced by Bacillus sp. strain HIL Y-85,54728. Mersacidin acts by complexing the sugar phosphate head group of the peptidoglycan precursor lipid II, thereby inhibiting the transglycosylation reaction of peptidoglycan biosynthesis.
Rainer Borriss - One of the best experts on this subject based on the ideXlab platform.
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The Genome of Plant Growth-Promoting Bacillus amyloliquefaciens subsp. plantarum Strain YAU B9601-Y2 Contains a Gene Cluster for Mersacidin Synthesis
Journal of bacteriology, 2012Co-Authors: Kun Hao, Jochen Blom, Christian Rueckert, Zichao Mao, Rainer BorrissAbstract:The genome of rhizobacterium Bacillus amyloliquefaciens subsp. plantarum YAU B9601-Y2 was 4.24 Mb in size and harbored 3,991 coding sequences (CDS). Giant gene clusters were dedicated to nonribosomal synthesis of antimicrobial lipopeptides and polyketides. Remarkably, CAU B946 possessed a gene cluster involved in synthesis of Mersacidin.
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Gene Cluster for Mersacidin Synthesis plantarum Strain YAU B9601-Y2 Contains a Bacillus amyloliquefaciens subsp. The Genome of Plant Growth-Promoting
2012Co-Authors: Zichao Mao, Kun Hao, Jochen Blom, Rainer Borriss, Christian RueckertAbstract:(3). The strain suppresses a broad spectrum of patho-genicfungi;promotesgrowthandrootingofcropsandvegetables;improves the drought tolerance of wheat, corn, and broad bean;and reduces the number of nematodes at tomato and tobaccoroots (Y. He, unpublished data).Genomic DNA prepared from YAU B9601-Y2 was used forconstruction of a 3-kb-long paired-end library with a GS FLXlibrary preparation kit in combination with GS FLX paired-endadaptors (both Roche, Mannheim, Germany) according to themanufacturer’s protocol. The reads were assembled using the GS
Kun Hao - One of the best experts on this subject based on the ideXlab platform.
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Genome sequence of the plant growth promoting strain Bacillus amyloliquefaciens subsp. plantarum B9601-Y2 and expression of Mersacidin and other secondary metabolites.
Journal of biotechnology, 2012Co-Authors: Kun Hao, Jochen Blom, Zichao Mao, Christian Rückert, Joachim Vater, Mingsheng Hou, He PengboAbstract:The plant-associated Bacillus amyloliquefaciens subsp. plantarum strain B9601-Y2, isolated from wheat rhizosphere, is a powerful plant growth-promoting rhizobacterium. Its relative large genome size of 4.24Mbp, exceeding that of other representatives of the B. amyloliquefaciens subsp. plantarum taxon, is mainly due to the presence of 18 DNA-islands containing remnants of phages, a unique restriction modification system, a gene cluster for Mersacidin synthesis, and an orphan gene cluster devoted to non-ribosomal synthesis of an unidentified peptide. Like other members of the taxon, the Y2 genome contains giant gene clusters for non-ribosomal synthesis of the polyketides macrolactin, difficidin, and bacillaene, the antifungal lipopeptides bacillomycin D, and fengycin, the siderophore bacillibactin, and the dipeptide bacilysin. A gene cluster encoding enzymes for a degradative pathway with 2-keto-3-deoxygluconate and 2-keto-3-deoxy-phosphogluconate as intermediates was explored by genome mining and found as being a unique feature for representatives of the plantarum subspecies. A survey of the Y2 genome against other B. amyloliquefaciens genomes revealed 130 genes only occurring in subsp. plantarum but not in subsp. amyloliquefaciens. Notably, the surfactin gene cluster is not functional due to a large deletion removing parts of the Srf synthetases B and C. Expression of polyketides, lipopeptides, Mersacidin, and of the growth hormone indole-3-acetic acid in Y2 was demonstrated by matrix-assisted laser desorption ionization-time of flight mass spectroscopy and high-performance liquid chromatography, respectively.
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The Genome of Plant Growth-Promoting Bacillus amyloliquefaciens subsp. plantarum Strain YAU B9601-Y2 Contains a Gene Cluster for Mersacidin Synthesis
Journal of bacteriology, 2012Co-Authors: Kun Hao, Jochen Blom, Christian Rueckert, Zichao Mao, Rainer BorrissAbstract:The genome of rhizobacterium Bacillus amyloliquefaciens subsp. plantarum YAU B9601-Y2 was 4.24 Mb in size and harbored 3,991 coding sequences (CDS). Giant gene clusters were dedicated to nonribosomal synthesis of antimicrobial lipopeptides and polyketides. Remarkably, CAU B946 possessed a gene cluster involved in synthesis of Mersacidin.
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Gene Cluster for Mersacidin Synthesis plantarum Strain YAU B9601-Y2 Contains a Bacillus amyloliquefaciens subsp. The Genome of Plant Growth-Promoting
2012Co-Authors: Zichao Mao, Kun Hao, Jochen Blom, Rainer Borriss, Christian RueckertAbstract:(3). The strain suppresses a broad spectrum of patho-genicfungi;promotesgrowthandrootingofcropsandvegetables;improves the drought tolerance of wheat, corn, and broad bean;and reduces the number of nematodes at tomato and tobaccoroots (Y. He, unpublished data).Genomic DNA prepared from YAU B9601-Y2 was used forconstruction of a 3-kb-long paired-end library with a GS FLXlibrary preparation kit in combination with GS FLX paired-endadaptors (both Roche, Mannheim, Germany) according to themanufacturer’s protocol. The reads were assembled using the GS
Zichao Mao - One of the best experts on this subject based on the ideXlab platform.
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Genome sequence of the plant growth promoting strain Bacillus amyloliquefaciens subsp. plantarum B9601-Y2 and expression of Mersacidin and other secondary metabolites.
Journal of biotechnology, 2012Co-Authors: Kun Hao, Jochen Blom, Zichao Mao, Christian Rückert, Joachim Vater, Mingsheng Hou, He PengboAbstract:The plant-associated Bacillus amyloliquefaciens subsp. plantarum strain B9601-Y2, isolated from wheat rhizosphere, is a powerful plant growth-promoting rhizobacterium. Its relative large genome size of 4.24Mbp, exceeding that of other representatives of the B. amyloliquefaciens subsp. plantarum taxon, is mainly due to the presence of 18 DNA-islands containing remnants of phages, a unique restriction modification system, a gene cluster for Mersacidin synthesis, and an orphan gene cluster devoted to non-ribosomal synthesis of an unidentified peptide. Like other members of the taxon, the Y2 genome contains giant gene clusters for non-ribosomal synthesis of the polyketides macrolactin, difficidin, and bacillaene, the antifungal lipopeptides bacillomycin D, and fengycin, the siderophore bacillibactin, and the dipeptide bacilysin. A gene cluster encoding enzymes for a degradative pathway with 2-keto-3-deoxygluconate and 2-keto-3-deoxy-phosphogluconate as intermediates was explored by genome mining and found as being a unique feature for representatives of the plantarum subspecies. A survey of the Y2 genome against other B. amyloliquefaciens genomes revealed 130 genes only occurring in subsp. plantarum but not in subsp. amyloliquefaciens. Notably, the surfactin gene cluster is not functional due to a large deletion removing parts of the Srf synthetases B and C. Expression of polyketides, lipopeptides, Mersacidin, and of the growth hormone indole-3-acetic acid in Y2 was demonstrated by matrix-assisted laser desorption ionization-time of flight mass spectroscopy and high-performance liquid chromatography, respectively.
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The Genome of Plant Growth-Promoting Bacillus amyloliquefaciens subsp. plantarum Strain YAU B9601-Y2 Contains a Gene Cluster for Mersacidin Synthesis
Journal of bacteriology, 2012Co-Authors: Kun Hao, Jochen Blom, Christian Rueckert, Zichao Mao, Rainer BorrissAbstract:The genome of rhizobacterium Bacillus amyloliquefaciens subsp. plantarum YAU B9601-Y2 was 4.24 Mb in size and harbored 3,991 coding sequences (CDS). Giant gene clusters were dedicated to nonribosomal synthesis of antimicrobial lipopeptides and polyketides. Remarkably, CAU B946 possessed a gene cluster involved in synthesis of Mersacidin.
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Gene Cluster for Mersacidin Synthesis plantarum Strain YAU B9601-Y2 Contains a Bacillus amyloliquefaciens subsp. The Genome of Plant Growth-Promoting
2012Co-Authors: Zichao Mao, Kun Hao, Jochen Blom, Rainer Borriss, Christian RueckertAbstract:(3). The strain suppresses a broad spectrum of patho-genicfungi;promotesgrowthandrootingofcropsandvegetables;improves the drought tolerance of wheat, corn, and broad bean;and reduces the number of nematodes at tomato and tobaccoroots (Y. He, unpublished data).Genomic DNA prepared from YAU B9601-Y2 was used forconstruction of a 3-kb-long paired-end library with a GS FLXlibrary preparation kit in combination with GS FLX paired-endadaptors (both Roche, Mannheim, Germany) according to themanufacturer’s protocol. The reads were assembled using the GS