TY  - JOUR
A1  - Cheenakula, Dheeraja
A1  - Paulsen, Svea
A1  - Ott, Fabian
A1  - Grömping, Markus
T1  - Operational window of a deammonifying sludge for mainstream application in a municipal wastewater treatment plant
JF  - Water and Environment Journal
N2  - The present work aimed to study the mainstream feasibility of the deammonifying sludge of side stream of municipal wastewater treatment plant (MWWTP) in Kaster, Germany. For this purpose, the deammonifying sludge available at the side stream was investigated for nitrogen (N) removal with respect to the operational factors temperature (15–30°C), pH value (6.0–8.0) and chemical oxygen demand (COD)/N ratio (≤1.5–6.0). The highest and lowest N-removal rates of 0.13 and 0.045 kg/(m³ d) are achieved at 30 and 15°C, respectively. Different conditions of pH and COD/N ratios in the SBRs of Partial nitritation/anammox (PN/A) significantly influenced both the metabolic processes and associated N-removal rates. The scientific insights gained from the current work signifies the possibility of mainstream PN/A at WWTPs. The current study forms a solid basis of operational window for the upcoming semi-technical trails to be conducted prior to the full-scale mainstream PN/A at WWTP Kaster and WWTPs globally.
KW  - Anammox
KW  - Mainstream
KW  - Nitrogen removal
KW  - Partial nitritation
KW  - Wastewater
Y1  - 2023
U6  - https://doi.org/10.1111/wej.12898
SN  - 1747-6593
N1  - Corresponding author: Dheeraja Cheenakula
VL  - 38
IS  - 1
SP  - 59
EP  - 70
PB  - Wiley
CY  - Chichester
ER  - 
TY  - JOUR
A1  - Haeger, Gerrit
A1  - Probst, Johanna
A1  - Jaeger, Karl-Erich
A1  - Bongaerts, Johannes
A1  - Siegert, Petra
T1  - Novel aminoacylases from Streptomyces griseus DSM 40236 and their recombinant production in Streptomyces lividans
JF  - FEBS Open Bio
N2  - Amino acid-based surfactants are valuable compounds for cosmetic formulations. The chemical synthesis of acyl-amino acids is conventionally performed by the Schotten-Baumann reaction using fatty acyl chlorides, but aminoacylases have also been investigated for use in biocatalytic synthesis with free fatty acids. Aminoacylases and their properties are diverse; they belong to different peptidase families and show differences in substrate specificity and biocatalytic potential. Bacterial aminoacylases capable of synthesis have been isolated from Burkholderia, Mycolicibacterium, and Streptomyces. Although several proteases and peptidases from S. griseus have been described, no aminoacylases from this species have been identified yet. In this study, we investigated two novel enzymes produced by S. griseus DSM 40236ᵀ . We identified and cloned the respective genes and recombinantly expressed an α-aminoacylase (EC 3.5.1.14), designated SgAA, and an ε-lysine acylase (EC 3.5.1.17), designated SgELA, in S. lividans TK23. The purified aminoacylase SgAA was biochemically characterized, focusing on its hydrolytic activity to determine temperature- and pH optima and stabilities. The aminoacylase could hydrolyze various acetyl-amino acids at the Nα -position with a broad specificity regarding the sidechain. Substrates with longer acyl chains, like lauroyl-amino acids, were hydrolyzed to a lesser extent. Purified aminoacylase SgELA specific for the hydrolysis of Nε -acetyl-L-lysine was unstable and lost its enzymatic activity upon storage for a longer period but could initially be characterized. The pH optimum of SgELA was pH 8.0. While synthesis of acyl-amino acids was not observed with SgELA, SgAA catalyzed the synthesis of lauroyl-methionine.
KW  - Streptomyces lividans
KW  - recombinant expression
KW  - Streptomyces griseus
KW  - ε-lysine acylase
KW  - α-aminoacylase
Y1  - 2023
U6  - https://doi.org/10.1002/2211-5463.13723
SN  - 2211-5463
N1  - Corresponding author: Petra Siegert
VL  - 13
IS  - 12
SP  - 2224
EP  - 2238
PB  - Wiley
CY  - Hoboken, NJ
ER  -