@article{FalkenbergVossBottetal.2023,
  author    = {Falkenberg, Fabian and Voß, Leonie and Bott, Michael and Bongaerts, Johannes and Siegert, Petra},
  title     = {New robust subtilisins from halotolerant and halophilic Bacillaceae},
  series = {Applied Microbiology and Biotechnology},
  volume    = {107},
  journal   = {Applied Microbiology and Biotechnology},
  publisher = {Springer Nature},
  address   = {Berlin},
  issn      = {1432-0614},
  doi       = {10.1007/s00253-023-12553-w},
  pages     = {3939 -- 3954},
  year      = {2023},
  abstract  = {The aim of the present study was the characterisation of three true subtilisins and one phylogenetically intermediate subtilisin from halotolerant and halophilic microorganisms. Considering the currently growing enzyme market for efficient and novel biocatalysts, data mining is a promising source for novel, as yet uncharacterised enzymes, especially from halophilic or halotolerant Bacillaceae, which offer great potential to meet industrial needs. Both halophilic bacteria Pontibacillus marinus DSM 16465ᵀ and Alkalibacillus haloalkaliphilus DSM 5271ᵀ and both halotolerant bacteria Metabacillus indicus DSM 16189 and Litchfieldia alkalitelluris DSM 16976ᵀ served as a source for the four new subtilisins SPPM, SPAH, SPMI and SPLA. The protease genes were cloned and expressed in Bacillus subtilis DB104. Purification to apparent homogeneity was achieved by ethanol precipitation, desalting and ion-exchange chromatography. Enzyme activity could be observed between pH 5.0-12.0 with an optimum for SPPM, SPMI and SPLA around pH 9.0 and for SPAH at pH 10.0. The optimal temperature for SPMI and SPLA was 70 °C and for SPPM and SPAH 55 °C and 50 °C, respectively. All proteases showed high stability towards 5\% (w/v) SDS and were active even at NaCl concentrations of 5 M. The four proteases demonstrate potential for future biotechnological applications.},
  language  = {en}
}
@article{FalkenbergKohnBottetal.2023,
  author    = {Falkenberg, Fabian and Kohn, Sophie and Bott, Michael and Bongaerts, Johannes and Siegert, Petra},
  title     = {Biochemical characterisation of a novel broad pH spectrum subtilisin from Fictibacillus arsenicus DSM 15822ᵀ},
  series = {FEBS Open Bio},
  volume    = {13},
  journal   = {FEBS Open Bio},
  number    = {11},
  publisher = {Wiley},
  address   = {Hoboken, NJ},
  issn      = {2211-5463},
  doi       = {10.1002/2211-5463.13701},
  pages     = {2035 -- 2046},
  year      = {2023},
  abstract  = {Subtilisins from microbial sources, especially from the Bacillaceae family, are of particular interest for biotechnological applications and serve the currently growing enzyme market as efficient and novel biocatalysts. Biotechnological applications include use in detergents, cosmetics, leather processing, wastewater treatment and pharmaceuticals. To identify a possible candidate for the enzyme market, here we cloned the gene of the subtilisin SPFA from Fictibacillus arsenicus DSM 15822ᵀ (obtained through a data mining-based search) and expressed it in Bacillus subtilis DB104. After production and purification, the protease showed a molecular mass of 27.57 kDa and a pI of 5.8. SPFA displayed hydrolytic activity at a temperature optimum of 80 °C and a very broad pH optimum between 8.5 and 11.5, with high activity up to pH 12.5. SPFA displayed no NaCl dependence but a high NaCl tolerance, with decreasing activity up to concentrations of 5 m NaCl. The stability enhanced with increasing NaCl concentration. Based on its substrate preference for 10 synthetic peptide 4-nitroanilide substrates with three or four amino acids and its phylogenetic classification, SPFA can be assigned to the subgroup of true subtilisins. Moreover, SPFA exhibited high tolerance to 5\% (w/v) SDS and 5\% H₂O₂ (v/v). The biochemical properties of SPFA, especially its tolerance of remarkably high pH, SDS and H₂O₂, suggest it has potential for biotechnological applications.},
  language  = {en}
}