Amicon stirred cell concentrators

Chemicals, biochemicals, and buffers were purchased from Sigma-Aldrich Chemical Co. (St. Louis, MO), Fisher Scientific, Inc. (Pittsburgh, PA), EMD Millipore, Inc. (Billerica, MA) or Bio-Rad Laboratories, Inc. (Hercules, CA), unless otherwise noted below. Phenylenolpyruvate (PP) was purchased from Fluka Chemical Corp. (Milwaukee, WI) as the crystalline free acid, which exists in the enol form. 2-Oxo-3-pentynoate (2-OP) was synthesized, as described elsewhere.^{21 (link)} The compounds in the substrate library were obtained from sources reported elsewhere.²³ The DEAE-Sepharose fast flow resin and the PD-10 Sephadex G-25M buffer-exchange columns were obtained from GE Healthcare Bio-Sciences (Pittsburgh, PA). The Econo-Column chromatography columns (used for the DEAE-Sepharose columns) were obtained from Bio-Rad Laboratories, Inc. (Hercules, CA). The Amicon stirred cell concentrators and the ultrafiltration membranes (10000 Da, MW cutoff) were purchased from EMD Millipore Inc. (Billerica, MA). InstantBlue for staining sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels was obtained from C.B.S. Scientific Company, Inc. (Del Mar, CA).

Chemicals, biochemicals, buffers, and solvents were purchased from Sigma-Aldrich Chemical Co. (St. Louis, MO), Fisher Scientific Inc. (Pittsburgh, PA), Fluka Chemical Corp. (Milwaukee, WI), or EMD Millipore, Inc. (Billerica, MA). Sodium phosphate buffer salts were at least 99.99% pure or greater, as indicated by the manufacturer. Propiolic acid (98%, 8) and 2-butynoate (10) were purchased from Sigma- Aldrich. Both were purified further prior to use by distillation (8) or recrystallization (10). 2,3-Butadienoate (9) was synthesized according to published methods.¹⁴ The DEAE- Sepharose and Phenyl-Sepharose 6 Fast Flow resins used for protein purification were obtained from Sigma-Aldrich Chemical Co. (St Louis, MO). The Econo-Column chroma- tography columns were obtained from BioRad (Hercules, CA). The Amicon stirred cell concentrators and the ultrafiltration membranes (10000 Da, MW cutoff) were purchased from EMD Millipore Inc. Malonate semialdehyde decarboxylase (MSAD) was purified as described previously.^{10 (link)}

Chemicals, biochemicals, buffers, and solvents were purchased from Sigma-Aldrich Chemical Co. (St. Louis, MO), Fisher Scientific Inc. (Pittsburgh, PA), Fluka Chemical Corp. (Milwaukee, WI), or EMD Millipore, Inc. (Billerica, MA). 2-Carboxybenzaldehyde (10) was obtained from Sigma-Aldrich Chemical Co. Phenyl-Sepharose 6 Fast Flow resin was obtained from GE Healthcare Bio-sciences (Pittsburgh, PA). The Econo-Column^® chromatography columns were obtained from BioRad (Hercules, CA). The Amicon stirred cell concentrators and the ultrafiltration membranes (10,000 Da, MW cutoff) were purchased from EMD Millipore Inc. Oligonucleotide primers were synthesized by Sigma-Aldrich.