Example 66
The activity of SYN-PKU-2002 was assessed in vivo. To prepare the cells for the study, SYN-PKU901 and SYN-PKU-2002 overnight cultures were each used to inoculate 4 2 L flasks containing 500 mL of LB with DAP100 ug/mL. These cultures were grown for 1 hr and 45 min and then moved to the anaerobic chamber supplying 90% N2, 5% CO2, and 5% H2 for 4 hours. Cells were then spun down at 4600×G for 12 min and resuspended in 10 mL of formulation buffer (Glycerol: 15% (v/v), Sucrose: 10% (w/v) (100 g/L), MOPS: 10 mM (2.1 g/L), NaCl: 25 mM (1.46 g/L)). Several 40 ul aliquots were removed to be used for cell counting and activity determination. The viability as determined by cellometer count (in quadruplicate) 6.94e10 cfu/ml (+/−5.78e9).
Activity was determined using a plate based assay. Briefly, 1×108 cfu as determined by cellometer were added to 1 ml of prewarmed assay buffer (1× M9 minimal media containing 0.5% glucose, 50 mM MOPS, and 50 mM phenylalanine) in a microfuge tube, vortexed briefly, and immediately placed in a heat block or water bath at 37 degrees Celsius for static incubation (t=0). Supernatant samples from cells re-suspended in assay buffer were analyzed for the abundance of TCA over several time points using spectrophotometer at an absorbance of 290 nm. The accurate OD290 window for TCA detection occurs in a relatively narrow concentration range. For this reason, supernatant samples were diluted to ensure that the absorbance measurement fell into the linear range for detection. Measurements were compared to a TCA standard curve. Activity was determined to be 2.72 umol/hr/le9 cfu (+/−0.15 umol/hr/le9 cfu).
Beginning 4 days prior to the study (i.e., Days −4-1), Pah ENU2/2 mice (˜11-15 weeks of age) were maintained on phenylalanine-free chow and water that was supplemented with 0.5 grams/L phenylalanine. On the day of the study, mice were randomized into treatment groups according to weight as follows: Group 1: SYN-PKU901 (n=9); Group 2: Group 2: SYN-PKU-2002 (n=9). Blood samples were collected by sub-mandibular skin puncture to determine baseline phenylalanine levels. Mice were then administered single dose of phenylalanine by subcutaneous injection at 0.1 mg per gram body weight, according to the average group weight. At 1, 2 and 3 h post Phe challenge, the bacteria (or water) were administered to mice by oral gavage (3×250 ul). Whole blood was collected via submandibular bleed at each time point. Urine collection in metabolic caging commenced immediately after the 1st bacterial dose and continued to be collected for the duration of the study (4 hours).
Blood samples were kept on ice until processing for plasma in a centrifuge (2000 g for 10 min at 4 C) within 20 min of collection. Plasma was then transferred into a 96-well plate for MS analysis. Urine was collected in 5 mL tubes and volumes were recorded before transferring samples to MS for analysis. Results are shown in
