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The TAL activity of the DPD5154 strain was analyzed as follows. Fresh colonies were separately inoculated into 5.0 ml of LB medium supplemented with 50 μg/ml spectinomycin and incubated overnight at 37° C. with shaking at 250 rpm. Each culture was then diluted to an optical density (OD600) of 0.02 in the LB medium with 50 μg/ml spectinomycin and grown to an OD600 of 0.4, before being induced with 0.02% L-arabinose. The induced cultures were incubated for 20 hours at 37° C. with shaking at 250 rpm after which the cells were pelleted by centrifugation at 2,300×g, 4° C. for 30 minutes in a Beckman GS-6R (Fullerton, Calif.) centrifuge. The pellets were re-suspended in 2.0 ml of ice cold 50 mM Tris-HCl, pH 8.5 containing the Protease inhibitor cocktail (Roche, Palo Alto, Calif.), transferred to ice cold 15 ml sterile conical tubes and sonicated in a Fisher Sonic Model 300 Dismembrator (Pittsburgh, Pa.) at 50% power repeating four cycles of 30 seconds sonication with 60 seconds rest in between each cycle. The samples were kept in an ice bath during the entire procedure. Each sonicated sample was centrifuged at 15,000×g for 30 minutes at 4° C. to separate the crude cell extracts into soluble (supernatant) and insoluble (pellet) protein fractions. The resulting pellet was re-suspended in 1.0 ml of ice cold 50 mM Tris, pH 8.5 containing the Protease inhibitor cocktail. The protein concentration of each soluble sample was determined using the Bradford protein assay (Bio-Rad, Hercules, Calif.). Each sample was diluted with 50 mM Tris-HCl, pH 8.5 until the optical density (595 nm) was in the linear range of a bovine serum albumin (BSA) standard curve which ranged from 0.125-1.0 mg/ml. The TAL activity was determined for soluble protein samples by measuring production of pHCA from tyrosine. A 1.0 ml reaction containing 40 μg of soluble protein sample, 100 mM CAPS pH10 buffer and 10 mM tyrosine was monitored in a 1.5 ml UV grade disposable cuvette (VWR) for 3 minutes at 35° C. Absorption at λ315 nm was measured using a Perkin-Elmer Lamba20 spectrophotometer (Wellesley, Mass.) and was converted to U/g of TAL activity as follows: Total TAL Activity (μmol/min)=Δ315 nm (/min)×1,000,000 (μM/M)/pHCA extinction coefficient (M−1 cm−1)]=Δ315 nm (/min)×(1,000,000 (μmol/mol)/16,800 mol−1 cm−1) TAL Specific Activity (U/g)=Total TAL Activity (μmol/min)/amount of TAL protein used in rxn=Total TAL Activity (μmol/L/min)/0.040(g/L)=Δ315 nm×1480 (U/g) The TAL activities in the soluble crude extracts of DPD5154 were measured for two clones and results are shown in Table 5. TAL activity was measured in units per gram of soluble proteins as described in General Methods.

1. stirringwith shaking at 250 rpm after which the cells
2. waitwere pelleted by centrifugation at 2,300×g, 4° C. for 30 minutes in a Beckman GS-6R (Fullerton, Calif.) centrifuge
3. additionpH 8.5 containing the Protease inhibitor cocktail (Roche, Palo Alto, Calif.)
4. customsonicated in a Fisher Sonic Model 300 Dismembrator (Pittsburgh, Pa.) at 50% power
5. customfour cycles of 30 seconds sonication with 60 seconds rest in between each cycle
6. customThe samples were kept in an ice bath during the entire procedure
7. waitEach sonicated sample was centrifuged at 15,000×g for 30 minutes at 4° C.
8. customto separate the crude cell extracts into soluble (supernatant) and insoluble (pellet) protein fractions
9. additionpH 8.5 containing the Protease inhibitor cocktail
10. additionEach sample was diluted with 50 mM Tris-HCl, pH 8.5 until the optical density (595 nm)
11. customA 1.0 ml reaction
12. waitwas monitored in a 1.5 ml UV grade disposable cuvette (VWR) for 3 minutes at 35° C
13. customAbsorption at λ315 nm
14. customresults