@article{GutschmannSimoesSchieweetal.2022,
  author    = {Gutschmann, Bj{\"o}rn and Sim{\~o}es, Matilde Maldonado and Schiewe, Thomas and Schr{\"o}ter, Edith S. and M{\"u}nzberg, Marvin and Neubauer, Peter and Bockisch, Anika and Riedel, Sebastian Lothar Stefan},
  title     = {Continuous feeding strategy for polyhydroxyalkanoate production from solid waste animal fat at laboratory- and pilot-scale},
  series = {Microbial biotechnology / Society for Applied Microbiology},
  journal   = {Microbial biotechnology / Society for Applied Microbiology},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1751-7915},
  doi       = {10.1111/1751-7915.14104},
  pages     = {12},
  year      = {2022},
  abstract  = {Bioconversion of waste animal fat (WAF) to polyhydroxyalkanoates (PHAs) is an approach to lower the production costs of these plastic alternatives. However, the solid nature of WAF requires a tailor-made process development. In this study, a double-jacket feeding system was built to thermally liquefy the WAF to employ a continuous feeding strategy. During laboratory-scale cultivations with Ralstonia eutropha Re2058/pCB113, 70\% more PHA (45 g(PHA) L-1) and a 75\% higher space-time yield (0.63 g(PHA) L-1 h(-1)) were achieved compared to previously reported fermentations with solid WAF. During the development process, growth and PHA formation were monitored in real-time by in-line photon density wave spectroscopy. The process robustness was further evaluated during scale-down fermentations employing an oscillating aeration, which did not alter the PHA yield although cells encountered periods of oxygen limitation. Flow cytometry with propidium iodide staining showed that more than two-thirds of the cells were viable at the end of the cultivation and viability was even little higher in the scale-down cultivations. Application of this feeding system at 150-L pilot-scale cultivation yielded in 31.5 g(PHA) L-1, which is a promising result for the further scale-up to industrial scale.},
  language  = {en}
}
@article{AvcilarKucukgozeBartholomaeusVarelaetal.2016,
  author    = {Avcilar-Kucukgoze, Irem and Bartholom{\"a}us, Alexander and Varela, Juan A. Cordero and Kaml, Robert Franz-Xaver and Neubauer, Peter and Budisa, Nediljko and Ignatova, Zoya},
  title     = {Discharging tRNAs: a tug of war between translation and detoxification in Escherichia coli},
  series = {Nucleic acids research},
  volume    = {44},
  journal   = {Nucleic acids research},
  publisher = {Oxford Univ. Press},
  address   = {Oxford},
  issn      = {0305-1048},
  doi       = {10.1093/nar/gkw697},
  pages     = {8324 -- 8334},
  year      = {2016},
  abstract  = {Translation is a central cellular process and is optimized for speed and fidelity. The speed of translation of a single codon depends on the concentration of aminoacyl-tRNAs. Here, we used microarray-based approaches to analyze the charging levels of tRNAs in Escherichia coli growing at different growth rates. Strikingly, we observed a non-uniform aminoacylation of tRNAs in complex media. In contrast, in minimal medium, the level of aminoacyl-tRNAs is more uniform and rises to approximately 60\%. Particularly, the charging level of tRNA(Ser), tRNA(Cys), tRNA(Thr) and tRNA(His) is below 50\% in complex medium and their aminoacylation levels mirror the degree that amino acids inhibit growth when individually added to minimal medium. Serine is among the most toxic amino acids for bacteria and tRNAs(Ser) exhibit the lowest charging levels, below 10\%, at high growth rate although intracellular serine concentration is plentiful. As a result some serine codons are among the most slowly translated codons. A large fraction of the serine is most likely degraded by L-serine-deaminase, which competes with the seryl-tRNA-synthetase that charges the tRNAs(Ser). These results indicate that the level of aminoacylation in complex media might be a competition between charging for translation and degradation of amino acids that inhibit growth.},
  language  = {en}
}