Biomaterial Database

Phosphatase localization in the endomembrane system of the dinoflagellate Crypthecodinium cohnii. 1986

S B Barlow, and R E Triemer

The distribution of four enzymes within the endomembrane system of the protist Crypthecodinium cohnii has been determined using cytochemical localizations with lead as a capture agent. Nucleoside diphosphatase (NDPase) activity, using inosine diphosphate (IDP) and thiamine pyrophosphate (TPP) as substrates, was observed in the Golgi apparatus, with a gradient of increasing reaction product noted in some cells from the cis to trans cisternae. Tubules and vesicles associated with the trans cisternae also contained reaction product. The endoplasmic reticulum exhibited a high activity of glucose-6-phosphatase [with glucose-6-phosphate (G-6-P) as substrate]. Traces of reaction product were also observed in the cis-most and trans-most cisternae of the dictyosomes. Activity of acid phosphatase (AcPase) was observed in Golgi cisternae as well as in associated cytoplasmic vesicles. Heaviest deposition was localized in medial and trans dictyosome cisternae. The cytoplasmic system of flattened vesicles subtending the surface membranes in these cells did not exhibit reactivity with any of the substrates used. The distribution of these enzymes in this algal cell appears similar to that observed in animal cells and suggests that these enzymes may represent markers for algal cell endomembrane compartments.

UI	MeSH Term	Description	Entries
D010744	Phosphoric Monoester Hydrolases	A group of hydrolases which catalyze the hydrolysis of monophosphoric esters with the production of one mole of orthophosphate.	Phosphatase,Phosphatases,Phosphohydrolase,Phosphohydrolases,Phosphomonoesterase,Phosphomonoesterases,Phosphoric Monoester Hydrolase,Hydrolase, Phosphoric Monoester,Hydrolases, Phosphoric Monoester,Monoester Hydrolase, Phosphoric
D004141	Dinoflagellida	Flagellate EUKARYOTES, found mainly in the oceans. They are characterized by the presence of transverse and longitudinal flagella which propel the organisms in a rotating manner through the water. Dinoflagellida were formerly members of the class Phytomastigophorea under the old five kingdom paradigm.	Amphidinium,Dinoflagellata,Dinophyceae,Dinophycidae,Dinophyta,Dinophytes,Gambierdiscus toxicus,Gonyaulax,Gymnodinium,Peridinium,Pyrrhophyta,Pyrrophyta,Dinoflagellates
D004721	Endoplasmic Reticulum	A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)	Ergastoplasm,Reticulum, Endoplasmic
D005952	Glucose-6-Phosphatase	An enzyme that catalyzes the conversion of D-glucose 6-phosphate and water to D-glucose and orthophosphate. EC 3.1.3.9.	Glucosephosphatase,Glucose 6-Phosphatase,Glucose-6-Phosphate Phosphohydrolase,Glucose 6 Phosphatase
D006056	Golgi Apparatus	A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)	Golgi Complex,Apparatus, Golgi,Complex, Golgi
D000135	Acid Phosphatase	An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.2.	Acid beta-Glycerophosphatase,Acid beta Glycerophosphatase
D013834	Thiamine Pyrophosphatase	An enzyme that hydrolyzes thiamine pyrophosphate to thiamine monophosphate plus inorganic phosphate. EC 3.6.1.-.	TPPase,Thiamine Pyrophosphate Phosphohydrolase,Phosphohydrolase, Thiamine Pyrophosphate,Pyrophosphatase, Thiamine,Pyrophosphate Phosphohydrolase, Thiamine
D017766	Acid Anhydride Hydrolases	A group of enzymes that catalyze the hydrolysis of diphosphate bonds in compounds such as nucleoside di- and tri-phosphates, and sulfonyl-containing anhydrides such as adenylylsulfate. (Enzyme Nomenclature, 1992) EC 3.6.	Anhydride Hydrolases, Acid,Hydrolases, Acid Anhydride