Phosphorylation of the pyruvate dehydrogenase complex isolated from Ascaris suum

Conference · Fri May 01 04:00:00 EDT 1987 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6023696

Thissen, J; Komuniecki, R

The pyruvate dehydrogenase complex (PDC) from body wall muscle of the porcine nematode, Ascaris suum, plays a pivotal role in anaerobic mitochondrial metabolism. As in mammalian mitochondria, PDC activity is inhibited by the phosphorylation of the ..cap alpha..PDH subunit, catalyzed by an associated PDH/sub a/ kinase. However, in contrast to PDC's isolated from all other eukaryotic sources, phosphorylation decreases the mobility of the ..cap alpha..PDH subunit on SDS-PAGE and permits the separation of the phosphorylated and nonphosphorylated ..cap alpha..PDH's. Phosphorylation and the inactivation of the Ascaris PDC correspond directly, and the additional phosphorylation that occurs after complete inactivation in mammalian PDC's is not observed. The purified ascarid PDC incorporates 10 nmoles /sup 32/P/mg P. Autoradiography of the radiolabeled PDC separated by SDS-PAGE yields a band which corresponds to the phosphorylated ..cap alpha..PDH and a second, faint band which is present only during the first three minutes of PDC inactivation, intermediate between the phosphorylated and nonphosphorylated ..cap alpha..PDH subunit. Tryptic digests of the /sup 32/P-PDC yields one major phosphopeptide, when separated by HPLC, and its amino acid sequence currently is being determined.

• Research Organization: Univ. of Toledo, OH
• OSTI ID: 6023696
• Report Number(s): CONF-870644-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 46:6
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ASCARIDAE
ASCARIS
ASCHELMINTHES
AUTORADIOGRAPHY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CELL CONSTITUENTS
CHEMICAL REACTIONS
DAYS LIVING RADIOISOTOPES
ELECTROPHORESIS
ENZYME ACTIVITY
ENZYMES
HELMINTHS
ISOTOPES
LIGHT NUCLEI
MITOCHONDRIA
MUSCLES
NEMATODES
NUCLEI
ODD-ODD NUCLEI
ORGANOIDS
OXIDOREDUCTASES
PARASITES
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PHOSPHORYLATION
RADIOISOTOPES