Modification of amino acid and sugar transport in uncoupler-adapted Euglena gracilis.
Uncoupler-adapted Euglena gracilis have a greatly impaired capacity to take up and incorporate some exogenously supplied amino acids and sugars. The degree of inhibition varies widely from >90% in the case of valine or glucose to none in the case of histidine. The inhibition is due to a decreased activity of the transport mechanism itself and is not due to either a lesion in the control mechanism for endogenous amino acid or sugar synthesis nor to a direct inhibition of the transport mechanism by uncouplers. No preferential labeling of mitochondrial membranes by [14C]amino acids occurs during the process of adaptation, a time when no cell division occurs. Apparently, during the long time required for adaptation, there occurs no major modification of mitochondrial proteins which could explain the subsequent resistance to uncouplers.
Kahn
J S
JS
Department of Biochemistry, North Carolina State University, Raleigh, North Carolina 27607, USA.
McConnell
R T
RT
D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport / Q000502:physiology; D050260:Carbohydrate Metabolism / Q000502:physiology*; D002250:Carbon Radioisotopes / Q000378:metabolism; D005056:Euglena gracilis / Q000235:genetics / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism*; D009154:Mutation / Q000235:genetics
D000596:Amino Acids; D002250:Carbon Radioisotopes; D024101:Mitochondrial Proteins