Biomaterial Database

Protection of phenylalanine ammonia-lyase from proteolytic attack. 1985

H J Gilbert, and M Tully

Phenylalanine ammonia-lyase contained within permeabilized cells of Rhodosporidium toruloides was protected from proteolytic attack by trypsin, chymotrypsin and duodenal juice. The inactivation by the proteases was biphasic. The enzyme contained within the yeast cells had a similar Km for phenylalanine and Ki for cinnamic acid to the protein in free solution. Phenylalanine ammonia-lyase present in the yeast depleted duodenal juice of free phenylalanine, while the enzyme in free solution did not. The possibility of using permeabilized cells of R. toruloides as a vehicle for protecting orally ingested therapeutic enzymes from proteolytic inactivation is discussed.

UI	MeSH Term	Description	Entries
D007419	Intestinal Secretions	Fluids originating from the epithelial lining of the intestines, adjoining exocrine glands and from organs such as the liver, which empty into the cavity of the intestines.	Intestinal Secretion,Secretion, Intestinal,Secretions, Intestinal
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010447	Peptide Hydrolases	Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.	Peptidase,Peptidases,Peptide Hydrolase,Protease,Proteases,Proteinase,Proteinases,Proteolytic Enzyme,Proteolytic Enzymes,Esteroproteases,Enzyme, Proteolytic,Hydrolase, Peptide
D010649	Phenylalanine	An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.	Endorphenyl,L-Phenylalanine,Phenylalanine, L-Isomer,L-Isomer Phenylalanine,Phenylalanine, L Isomer
D010650	Phenylalanine Ammonia-Lyase	An enzyme that catalyzes the deamination of PHENYLALANINE to form trans-cinnamate and ammonia.	Phenylalanine-Tyrosine Ammonia-lyase,Ammonia-Lyase, Phenylalanine,Ammonia-lyase, Phenylalanine-Tyrosine,Phenylalanine Ammonia Lyase,Phenylalanine Tyrosine Ammonia lyase
D002463	Cell Membrane Permeability	A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.	Permeability, Cell Membrane
D002918	Chymotrypsin	A serine endopeptidase secreted by the pancreas as its zymogen, CHYMOTRYPSINOGEN and carried in the pancreatic juice to the duodenum where it is activated by TRYPSIN. It selectively cleaves aromatic amino acids on the carboxyl side.	Alpha-Chymotrypsin Choay,Alphacutanée,Avazyme
D002934	Cinnamates	Derivatives of cinnamic acid (the structural formula: phenyl-HC	Cinnamate
D004386	Duodenum	The shortest and widest portion of the SMALL INTESTINE adjacent to the PYLORUS of the STOMACH. It is named for having the length equal to about the width of 12 fingers.	Duodenums
D000642	Ammonia-Lyases	Enzymes that catalyze the formation of a carbon-carbon double bond by the elimination of AMMONIA. EC 4.3.1.	Ammonia Lyase,Ammonia-Lyase,Ammonia Lyases,Lyase, Ammonia