@article{RemesBerghoffFoerstneretal.2014,
  author    = {Remes, Bernhard and Berghoff, Bork A. and F{\"o}rstner, Konrad U. and Klug, Gabriele},
  title     = {Role of oxygen and the OxyR protein in the response to iron limitation in Rhodobacter sphaeroides},
  series = {BMC Genomics},
  volume    = {15},
  journal   = {BMC Genomics},
  number    = {794},
  issn      = {1471-2164},
  doi       = {10.1186/1471-2164-15-794},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115357},
  year      = {2014},
  abstract  = {Background: High intracellular levels of unbound iron can contribute to the production of reactive oxygen species (ROS) via the Fenton reaction, while depletion of iron limits the availability of iron-containing proteins, some of which have important functions in defence against oxidative stress. Vice versa increased ROS levels lead to the damage of proteins with iron sulphur centres. Thus, organisms have to coordinate and balance their responses to oxidative stress and iron availability. Our knowledge of the molecular mechanisms underlying the co-regulation of these responses remains limited. To discriminate between a direct cellular response to iron limitation and indirect responses, which are the consequence of increased levels of ROS, we compared the response of the alpha-proteobacterium Rhodobacter sphaeroides to iron limitation in the presence or absence of oxygen. Results: One third of all genes with altered expression under iron limitation showed a response that was independent of oxygen availability. The other iron-regulated genes showed different responses in oxic or anoxic conditions and were grouped into six clusters based on the different expression profiles. For two of these clusters, induction in response to iron limitation under oxic conditions was dependent on the OxyR regulatory protein. An OxyR mutant showed increased ROS production and impaired growth under iron limitation. Conclusion: Some R. sphaeroides genes respond to iron limitation irrespective of oxygen availability. These genes therefore reflect a "core iron response" that is independent of potential ROS production under oxic, iron-limiting conditions. However, the regulation of most of the iron-responsive genes was biased by oxygen availability. Most strikingly, the OxyR-dependent activation of a subset of genes upon iron limitation under oxic conditions, including many genes with a role in iron metabolism, revealed that elevated ROS levels were an important trigger for this response. OxyR thus provides a regulatory link between the responses to oxidative stress and to iron limitation in R. sphaeroides.},
  language  = {en}
}
@article{YuVogelFoerstner2018,
  author    = {Yu, Sung-Huan and Vogel, J{\"o}rg and F{\"o}rstner, Konrad U.},
  title     = {ANNOgesic: a Swiss army knife for the RNA-seq based annotation of bacterial/archaeal genomes},
  series = {GigaScience},
  volume    = {7},
  journal   = {GigaScience},
  doi       = {10.1093/gigascience/giy096},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-178942},
  year      = {2018},
  abstract  = {To understand the gene regulation of an organism of interest, a comprehensive genome annotation is essential. While some features, such as coding sequences, can be computationally predicted with high accuracy based purely on the genomic sequence, others, such as promoter elements or noncoding RNAs, are harder to detect. RNA sequencing (RNA-seq) has proven to be an efficient method to identify these genomic features and to improve genome annotations. However, processing and integrating RNA-seq data in order to generate high-resolution annotations is challenging, time consuming, and requires numerous steps. We have constructed a powerful and modular tool called ANNOgesic that provides the required analyses and simplifies RNA-seq-based bacterial and archaeal genome annotation. It can integrate data from conventional RNA-seq and differential RNA-seq and predicts and annotates numerous features, including small noncoding RNAs, with high precision. The software is available under an open source license (ISCL) at https://pypi.org/project/ANNOgesic/.},
  language  = {en}
}
@article{EskenGorisGadkarietal.2020,
  author    = {Esken, Jens and Goris, Tobias and Gadkari, Jennifer and Bischler, Thorsten and F{\"o}rstner, Konrad U. and Sharma, Cynthia M. and Diekert, Gabriele and Schubert, Torsten},
  title     = {Tetrachloroethene respiration in Sulfurospirillum species is regulated by a two-component system as unraveled by comparative genomics, transcriptomics, and regulator binding studies},
  series = {MicrobiologyOpen},
  volume    = {9},
  journal   = {MicrobiologyOpen},
  number    = {12},
  doi       = {10.1002/mbo3.1138},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225754},
  year      = {2020},
  abstract  = {Energy conservation via organohalide respiration (OHR) in dehalogenating Sulfurospirillum species is an inducible process. However, the gene products involved in tetrachloroethene (PCE) sensing and signal transduction have not been unambiguously identified. Here, genome sequencing of Sulfurospirillum strains defective in PCE respiration and comparative genomics, which included the PCE-respiring representatives of the genus, uncovered the genetic inactivation of a two-component system (TCS) in the OHR gene region of the natural mutants. The assumption that the TCS gene products serve as a PCE sensor that initiates gene transcription was supported by the constitutive low-level expression of the TCS operon in fumarate-adapted cells of Sulfurospirillum multivorans. Via RNA sequencing, eight transcriptional units were identified in the OHR gene region, which includes the TCS operon, the PCE reductive dehalogenase operon, the gene cluster for norcobamide biosynthesis, and putative accessory genes with unknown functions. The OmpR-family response regulator (RR) encoded in the TCS operon was functionally characterized by promoter-binding assays. The RR bound a cis-regulatory element that contained a consensus sequence of a direct repeat (CTATW) separated by 17 bp. Its location either overlapping the -35 box or 50 bp further upstream indicated different regulatory mechanisms. Sequence variations in the regulator binding sites identified in the OHR gene region were in accordance with differences in the transcript levels of the respective gene clusters forming the PCE regulon. The results indicate the presence of a fine-tuned regulatory network controlling PCE metabolism in dehalogenating Sulfurospirillum species, a group of metabolically versatile organohalide-respiring bacteria.},
  language  = {en}
}