4.4. O-acetyl-l-serine(thiol)lyase (OAS-TL) Enzymatic Activities and Protein Determination

One gram of fresh leaves and roots of P. maritimum was crushed by mortar in liquid nitrogen, and to the powder, 2 mL of lysis buffer (50 mM phosphate-buffer pH 7.5, 10 μM pyridoxal-5′-phosphate, and 1 mM dithiothreitol) were added. Lysates were cleared by centrifugation at 12000× g for 15 min at 4 °C. The supernatant represented the crude extract. The enzymatic activity of OAS-TL was measured according to Carfagna et al. [20]. The OAS-TL activity was related to the total soluble protein content of the samples. Protein amounts were determined using the reagent Protein Assay (Bio-Rad Laboratories GmbH, Vienna, Austria) based on the Bradford method [52] with bovine serum albumin as the standard.