Expression and purification of B2036-Alkyne evaluated by SDS-PAGE with Coomassie staining. (A) OD600 normalized crude cell lysates were evaluated for full-length expression of TRX-B2036-Y35pglY in the presence or absence of isopropyl-β-D-thiogalactopyranoside (IPTG) and propargyl tyrosine (pglY). (B) TRX-B2036-Alkyne purified by immobilized metal affinity chromatography (IMAC). (C) Pure B2036-Alkyne following Tobacco Etch Virus (TEV) protease digestion and inverse IMAC. Lanes were loaded as follows: lane 1: protein standards, lane 2: crude cell lysate without IPTG and without pglY, lane 3: crude cell lysate with both IPTG and pglY, lane 4: crude cell lysate with IPTG and without pglY, lane 5: purified TRX-B2036-Alkyne with TRX-B2036 truncation product as indicated, lane 6: pure B2036-Alkyne; loading was normalized to 1.00 OD600/ml for lanes 2–4; expected TRX-B2036-Alkyne MW = 33 kDa and truncation product = 15 kDa.