Purification and characterization of cystathionine γ-lyase from Lactobacillus fermentum DT41

• Published in: FEMS microbiology letters 1998-09, Vol.166 (2), p.197-202
• Main Authors: Smacchi, Emanuele, Gobbetti, Marco
• Format: Article
• Language: English
• Subjects: Amino acid catabolism; Amino Acids - analysis; Bacteriology; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; CHEESE; Cheese - microbiology; Cheese ripening; CHEESEMAKING; CISTATIONINA; CYSTATHIONINE; Cystathionine - metabolism; Cystathionine gamma-Lyase - antagonists & inhibitors; Cystathionine gamma-Lyase - isolation & purification; Cystathionine gamma-Lyase - metabolism; Cystathionine γ-lyase; Cysteine - metabolism; Electrophoresis, Polyacrylamide Gel; Enzyme Inhibitors - pharmacology; FABRICACION DEL QUESO; FABRICATION FROMAGERE; Food Microbiology; FROMAGE; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Lactobacillus - enzymology; LACTOBACILLUS FERMENTUM; LIASAS; LYASE; LYASES; MADURAMIENTO; Metabolism. Enzymes; Microbiology; Mission oriented research; MURISSAGE; Physiology and metabolism; QUESO; RIPENING; Substrate Specificity
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1016/S0378-1097(98)00332-2

A homo-tetrameric ca. 140-kDa cystathionine γ-lyase was purified to homogeneity from Lactobacillus fermentum DT41 by four chromatographic steps. This was the first enzyme responsible for amino acid catabolism purified from lactobacilli. The activity is pyridoxal-5′-phosphate dependent and the enzyme catalyzes the α,γ-elimination reaction of l-cystathionine producing l-cysteine, ammonia and α-ketobutyrate. The cystathionine γ-lyase produced a free thiol group, a keto acid component and ammonia from several amino acids, including l-cysteine and methionine, and amino acid derivatives. l-Cystine was the best substrate. The enzyme was stable in the conditions of cheese ripening and may contribute to the biosynthesis of sulfur-containing compounds.