Fig 2. MetC purification.

(A) A schematic illustration of a recombinant construct for MetC. The protein was N-terminally tagged with TEE-6×His-TF. After thrombin digestion, MetC was obtained. (B) Commassie Brilliant Blue R 250-stained SDS-PAGE analysis of the samples was performed following the expression and purification of MetC. Lane 1, the bacterial protein fraction; lane 2, the soluble protein fraction; lane 3, the fraction containing proteins not bound to the Co²⁺-TALON resin; lane 4, proteins washed from the Co²⁺-TALON resin with buffer B; lane 5, the combined fractions after elution with buffer C; lane 6, molecular mass standards; lane 7, protein after digestion with thrombin; lane 8, the combined MetC fractions after ion-exchange chromatography; lane 9, purified MetC after dialysis against buffer F. (C) A schematic of the MetC expression and purification process. For more details, see the Materials and Methods section.