putida and P. alcaligenes but forms an individual Selleckchem PLX3397 branch. The other two Proteobacteria identified pure cultures belonged to the genera Variovorax (SMX332) and Brevundimonas (SMXB12). The isolated Variovorax SMX332 fell into the Variovorax paradoxus/boronicumulans group with a sequence similarity >99% to V. paradoxus (EU169152). The Brevundimonas
sp. SMXB12 was clearly separated from its closest relatives Brevundimonas basaltis and B. lenta and formed its own branch. Both Actinobacteria affiliated pure cultures were identified as Microbacterium spp. and were embedded in a new phylogenetic tree as their phylogenetic position was too far from the other isolates (Figure 1B). The two isolated species were affiliated to two different clades clearly separated from M. lacus and M. aurum. Microbacterium sp. SMXB24 fell into the same group
as Microbacterium sp. 7 1 K and M. hatatonis but the branch length clearly showed separation. Microbacterium sp. SMX348 was closely related with a sequence similarity of >99% to Microbacterium sp. BR1 which was found to biodegrade SMX in an acclimated membrane bioreactor [29]. SMX biodegradation studies with check details pure cultures Setups with sterile biomass (heat-killed) and without biomass (abiotic control) proved SMX to be stable under the operating conditions. Therefore sorption onto biomass or other materials was shown to be negligible. Photodegradation was excluded by performing all experiments in the dark. To characterize biodegradation ability and rate and evaluate an optimal nutrient environment for SMX utilization of the isolated and identified 9 pure cultures, subsequent experiments were performed. In the presence of readily degradable carbon and/or nitrogen sources (Figures 2 and 3) SMX was faster biodegraded compared to setups with SMX as sole carbon/nitrogen source (Figure 3). 54 setups (three media for each of the 9 cultures in duplicate setups) with different nutrient compositions were set up and SMX biodegradation rates were evaluated using UV-AM values (Table 2). Different SMX biodegradation
patterns were observed Cell Penetrating Peptide proving that the presence or absence of readily degradable and complex nutrients significantly influenced biodegradation. Figure 2 Aerobic SMX biodegradation patterns of pure cultures in MSM-CN media. A, B) measured with UV-AM, initial SMX concentration 10 mg L-1. C, D) LC-UV analyses of SMX concentrations in the used pure cultures in MSM-CN. Determination was performed at experimental startup, after 4 and 10 days to verify UV-AM values. Asterisks indicate measured values below limit of Tipifarnib datasheet detection. Shown are mean values of SMX absorbance in duplicate experiments. Standard deviations were too low to be shown (<1%). Figure 3 Aerobic SMX biodegradation patterns of pure cultures in MSM media. A, B) measured with UV-AM, initial SMX concentration 10 mg L-1.