TY - JOUR

T1 - Unidirectional arginine transport in reconstituted plasma-membrane vesicles from yeast overexpressing CAN1

AU - Opekarová, M

AU - Caspari, Thomas

AU - Tanner, Widmar

PY - 1993/2/1

Y1 - 1993/2/1

N2 - Amino acids are accumulated in Saccharomyces cerevisiae by strictly unidirectional influx systems. To see whether cellular compartmentation causes this unusual amino-acid-transport behaviour, arginine transport was studied in plasma-membrane vesicles. The arginine permease gene CAN1 was overexpressed in S. cerevisiae RH218a and in a permease-deficient mutant RS453 (can1). Reconstituted plasma-membrane vesicles from these transformants, energized by incorporated cytochrome-c oxidase, showed 3-4-fold increased rates of arginine uptake compared to vesicles from wild-type cells. The KT values were 32.5 microM in vesicles from wild-type and 28.6 microM in vesicles from transformed cells; the corresponding in vivo values were 17.5 microM and 11.4 microM, respectively. It could be demonstrated that unidirectional arginine transport and accumulation also exist in vesicles; thus, unidirectional influx is not related to cellular compartmentation.

AB - Amino acids are accumulated in Saccharomyces cerevisiae by strictly unidirectional influx systems. To see whether cellular compartmentation causes this unusual amino-acid-transport behaviour, arginine transport was studied in plasma-membrane vesicles. The arginine permease gene CAN1 was overexpressed in S. cerevisiae RH218a and in a permease-deficient mutant RS453 (can1). Reconstituted plasma-membrane vesicles from these transformants, energized by incorporated cytochrome-c oxidase, showed 3-4-fold increased rates of arginine uptake compared to vesicles from wild-type cells. The KT values were 32.5 microM in vesicles from wild-type and 28.6 microM in vesicles from transformed cells; the corresponding in vivo values were 17.5 microM and 11.4 microM, respectively. It could be demonstrated that unidirectional arginine transport and accumulation also exist in vesicles; thus, unidirectional influx is not related to cellular compartmentation.

KW - Amino Acid Transport Systems

KW - Amino Acid Transport Systems, Basic

KW - Arginine

KW - Biological Transport

KW - Cell Membrane

KW - Gene Expression

KW - Kinetics

KW - Liposomes

KW - Membrane Transport Proteins

KW - Plasmids

KW - Saccharomyces cerevisiae

KW - Saccharomyces cerevisiae Proteins

KW - Transformation, Genetic

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1111/j.1432-1033.1993.tb17596.x

DO - 10.1111/j.1432-1033.1993.tb17596.x

M3 - Article

C2 - 8436127

VL - 211

SP - 683

EP - 688

JO - European Journal of Biochemistry

JF - European Journal of Biochemistry

SN - 0014-2956

IS - 3

ER -