Carnitine palmitoyl transferase activity in Morris Hepatoma 7777 mitochondria and its sensitivity to malonyl CoA inhibition

Conference · Thu May 01 04:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5122147

Woldegiorgis, G; Shrago, E

Earlier reports in the literature have indicated no detectable Carnitine Palymitoyl Transferase (CPT) activity in homogenates prepared from Morris Hepatoma 7777. In its study CPT activity in isolated mitochondria (mito) was measured by butanol extraction of the (/sup 3/H)palmitoyl carnitine formed as outlined by Bremer et al. Contrary to the earlier work where no appreciable activity of CPT was observed the authors find significant levels of CPT (2.6 nMol/min/mg protein) in isolated mito from Morris Hepatoma 7777 (MH 7777). The level of CPT activity observed in MH 7777 mito was, however, 36% lower compared to the host liver CPT activity (4.1 nMol/min/mg protein). The enzyme in MH 7777 mito showed 83% inhibition in the presence of 10 ..mu..M malonyl CoA, in agreement with the degree of sensitivity observed with the host liver isolated mito. On freeze thawing host mito, total CPT activity increased and the sensitivity of the enzyme to malonyl CoA decreased. Frozen thawed MH 7777 mito showed a similar response to malonyl CoA but no change in the total CPT level was observed. The authors results establish for the first time the presence of a malonyl CoA sensitive CPT in MH 7777 mito, which may have slightly different properties from normal due to the membrane environment of the enzyme.

• Research Organization: Univ. of Wisconsin, Madison
• OSTI ID: 5122147
• Report Number(s): CONF-8606151-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:6
• Country of Publication: United States
• Language: English

Related Subjects

550901* -- Pathology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
BODY
CARBOXYLIC ACIDS
CARNITINE
CELL CONSTITUENTS
COENZYMES
DIGESTIVE SYSTEM
DISEASES
ENZYME ACTIVITY
ENZYMES
FREEZING
GLANDS
HEPATOMAS
HYDROXY ACIDS
INHIBITION
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LIVER
MITOCHONDRIA
NEOPLASMS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANOIDS
ORGANS
SENSITIVITY
THAWING
TRACER TECHNIQUES
TRANSFERASES
TRITIUM COMPOUNDS
VITAMIN B GROUP
VITAMINS