KINETIC AND ALLOSTERIC COOPERATIVITY IN L-ADENOSINE TRANSPORT IN CHROMAFFIN CELLS - A MNEMONICAL TRANSPORTER

被引:26
作者
CASILLAS, T
DELICADO, EG
GARCIACARMONA, F
MIRASPORTUGAL, MT
机构
[1] UNIV COMPLUTENSE MADRID,FAC VET,DEPT BIOQUIM,MADRID 3,SPAIN
[2] UNIV MURCIA,FAC BIOL,DEPT BIOQUIM,MURCIA,SPAIN
关键词
D O I
10.1021/bi00214a020
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
In cultured chromaffin cells and plasma membrane vesicles from chromaffin tissue, the transport of D-[H-3]adenosine followed Michaelis-Menten saturation kinetics, with K(m) values of 1.5 +/- 0.3 muM and 1.9 +/- 0.2 muM, respectively. The transport of the isomer, L-[H-3]adenosine, showed sigmoidal kinetics in both preparations. In plasma membrane vesicles the S0.5 was 2.5 +/- 0.2 muM with a Hill coefficient of 2.8 and the V(max) value of 0.26 +/- 0.01 pmol s-1 (mg of protein)-1. In cultured chromaffin cells the kinetic parameters for L-[H-3]adenosine were S0.5 = 6.2 +/- 0.2 muM and a V(max) 19.7 +/- 0.5 pmol/min per 10(6) cells, with a pronounced positive cooperativity. The Hill coefficient was 4.9. The transport of the L-isomer in cultured cells followed Michaelis-Menten kinetics at the lowest concentrations employed, below 2 muM. On the basis of these results, we propose a kinetic model whereby the adenosine transporter functions mnemonically.
引用
收藏
页码:14203 / 14209
页数:7
相关论文
共 39 条
[1]   SYNTHESIS OF L-RIBOFURANOSE + L-ADENOSINE [J].
ACTON, EM ;
RYAN, KJ ;
GOODMAN, L .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1964, 86 (23) :5352-&
[2]   SEQUENCE, STRUCTURE AND ACTIVITY OF PHOSPHOGLYCERATE KINASE - POSSIBLE HINGE-BENDING ENZYME [J].
BANKS, RD ;
BLAKE, CCF ;
EVANS, PR ;
HASER, R ;
RICE, DW ;
HARDY, GW ;
MERRETT, M ;
PHILLIPS, AW .
NATURE, 1979, 279 (5716) :773-778
[3]  
BLASYNSKI C, 1991, NEUROSCI LETT, V121, P1
[4]  
BRADFORD MM, 1976, ANAL BIOCHEM, V72, P248, DOI 10.1016/0003-2697(76)90527-3
[5]  
CASILLAS T, 1992, REV ESP FISIOL, V48, P1
[6]   GLUCOSE TRANSPORTERS IN CHROMAFFIN CELLS - SUBCELLULAR-DISTRIBUTION AND CHARACTERIZATION [J].
DELICADO, EG ;
TORRES, M ;
MIRASPORTUGAL, MT .
FEBS LETTERS, 1988, 229 (01) :35-39
[7]   EFFECTS OF PHORBOL ESTERS AND SECRETAGOGUES ON NITROBENZYLTHIOINOSINE BINDING TO NUCLEOSIDE TRANSPORTERS AND NUCLEOSIDE UPTAKE IN CULTURED CHROMAFFIN CELLS [J].
DELICADO, EG ;
SEN, RP ;
MIRASPORTUGAL, MT .
BIOCHEMICAL JOURNAL, 1991, 279 :651-655
[8]   EFFECT OF 5'-(N-ETHYLCARBOXAMIDO)ADENOSINE ON ADENOSINE TRANSPORT IN CULTURED CHROMAFFIN CELLS [J].
DELICADO, EG ;
RODRIGUES, A ;
SEN, RP ;
SEBASTIAO, AM ;
RIBEIRO, JA ;
MIRASPORTUGAL, MT .
JOURNAL OF NEUROCHEMISTRY, 1990, 54 (06) :1941-1946
[9]   LONG-TERM REGULATION OF NUCLEOSIDE TRANSPORT BY THYROID-HORMONE (T3) IN CULTURED CHROMAFFIN CELLS [J].
FIDEU, MD ;
MIRASPORTUGAL, MT .
NEUROCHEMICAL RESEARCH, 1992, 17 (11) :1099-1104
[10]   PHOTOAFFINITY-LABELING OF A NITROBENZYLTHIOINOSINE-BINDING POLYPEPTIDE FROM CULTURED NOVIKOFF HEPATOMA-CELLS [J].
GATI, WP ;
BELT, JA ;
JAKOBS, ES ;
YOUNG, JD ;
JARVIS, SM ;
PATERSON, ARP .
BIOCHEMICAL JOURNAL, 1986, 236 (03) :665-670