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The effects of cyclopropenoid fatty acids on structural components of microsomal membranes

Studies were conducted to determine the effects of cyclopropenoid
fatty acids (CPFA) on the microsomal membrane of livers of rainbow
trout (Salmo gairdneri). Slab and tube gel electrophoresis of
microsomes from trout fed a CPFA diet (CPFA-microsomes) for varying
time periods showed a decrease in the number of protein bands resolved
in the high molecular weight region. This disappearance of
high molecular weight proteins was not due to increased proteolysis
in the CPFA-microsomes.
Antibodies against whole microsomal protein from livers of
trout fed 300 ppm CPFA were produced in rabbits. Microsomal proteins
were first separated by polyacrylamide gel electrophoresis
(PAGE), transferred to nitrocellulose sheets (NC) and analyzed by
the peroxidase-antiperoxidase (PAP) immunochemical staining procedure.
Immunoabsorption of antisera directed against CPFA-microsomes
by control-microsomes did not reveal any new proteins induced
by the CPFA diets. However, the intensity of PAP staining was much
greater in CPFA microsomes after immunoabsorption.
Hydrolysis of phospholipids in the microsomal membrane by
phospholipase A₂ failed to reveal any differences between control
and CPFA fed trout. Proteolysis of microsomal membrane proteins
had similar effects on NADPH cytochrome reductase and cytochrome
P-450 activity on fish fed the different diets. PAGE analysis of
these digests did show some differences in digested proteins between the control and CPFA group. These results may reflect a possible
change in orientation of microsomal membrane proteins brought
about by CPFA in the diet. Additional evidence for altered orientation
of proteins was found with PAGE analysis of trypsin-digested
microsomes. Moreover incubation of trypsin-digested microsomes
with antisera and stained with PAP showed that proteolytic attack
was different between control and CPFA microsomes. A final study
with incubation of transferred proteins from control and CPFA-microsomes
with antisera directed against purified cytochrome P-450
(P-450) and cytochrome P-448 (P-448) showed that CPFA had an effect
on the concentration of P-448 but not P-450. / Graduation date: 1983

Identiferoai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/27449
Date14 December 1982
CreatorsMorrissey, Michael Thomas
ContributorsSelivonchick, Daniel P.
Source SetsOregon State University
Languageen_US
Detected LanguageEnglish
TypeThesis/Dissertation

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