Biomaterial Database

Guinea pig liver microsomal UDP-glucuronyltransferase: compartmented or phospholipid-constrained? 1975

C Berry, and A Stellon, and T Hallinan

1. Three mechanical methods for disrupting membranes substantially stimulated two forward reactions and a reverse reaction of UDPglucuronyltransferase (EC 2.4.1.1.7) in guinea-pig liver microsomes. Stimulation of glucuronyltransferase was highly significant and at lease as extensive as that of nucleoside diphosphatase, reportedly a marker intracisternal enzyme. 2. Stimulation of glucuronyltransferase did not appear to be caused by induction of lipid peroxidation or by lipid hydrolysis during membrane disruption. 3. Addition of phospholipid dispersions failed to significantly re-constrain glucuronyltransferase stimulated by mechanical disruption and did not markedly inhibit the enzyme in untreated control microsomes. 4. Compartmentation appears at least as feasible an explanation for the latency of glucuronyltransferase in guinea-pig liver microsomes as is its conformational constraint by membrane phospholipids. Compartmentation of glucuronyltransferase is functionally attractive since it would ensure its effective interaction with nucleoside diphosphatase on the cisternal side of the endoplasmic reticulum. This would tend to make conjugation reactions unidirectional.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D008297	Male		Males
D008566	Membranes	Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.	Membrane Tissue,Membrane,Membrane Tissues,Tissue, Membrane,Tissues, Membrane
D008862	Microsomes, Liver	Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.	Liver Microsomes,Liver Microsome,Microsome, Liver
D010713	Phosphatidylcholines	Derivatives of PHOSPHATIDIC ACIDS in which the phosphoric acid is bound in ester linkage to a CHOLINE moiety.	Choline Phosphoglycerides,Choline Glycerophospholipids,Phosphatidyl Choline,Phosphatidyl Cholines,Phosphatidylcholine,Choline, Phosphatidyl,Cholines, Phosphatidyl,Glycerophospholipids, Choline,Phosphoglycerides, Choline
D010743	Phospholipids	Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.	Phosphatides,Phospholipid
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D006602	Hexosyltransferases	Enzymes that catalyze the transfer of hexose groups. EC 2.4.1.-.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia