Ultrasensitive glycogen synthesis in Cyanobacteria

被引：20

作者：

Casati, DFG ^{[1
]}

Aon, MA ^{[1
]}

Iglesias, AA ^{[1
]}

机构：

[1] Inst Tecnol Chascomus, INTECH CONICET, RA-7130 Chascomus, Argentina

来源：

FEBS LETTERS | 1999年 / 446卷 / 01期

关键词：

ADPglucose pyrophosphorylase; glycogen and starch biosynthesis; enzyme regulation; molecular crowding; Anabaena PCC 7120;

D O I：

10.1016/S0014-5793(99)00201-X

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：

Cyanobacter ADPglucose pyrophosphorylase exhibits a ultrasensitive response in activity towards its allosteric effector 3-phosphoglycerate, elicited by orthophosphate and polyethyleneglycol-induced molecular crowding, The ultrasensitive response was observed either when the enzyme operates in the zero or first order region for its physiological substrates, The ultrasensitivity exhibited maximal amplification factors of 15-19-fold with respect to 1% of the maximal system velocity. Only a 2.4-3.8-fold increase in 3PGA concentration was necessary to augment the flux from 10% to 90% through AGPase as compared with 200-fold required for the control. The results are discussed in terms of finely tuned regulatory mechanisms of polysaccharide synthesis in oxygenic photosynthetic organisms. (C) 1999 Federation of European Biochemical Societies.

引用

页码：117 / 121

页数：5

共 24 条

[1] [Anonymous], 1991, OXFORD SURVEYS PLANT
[2] Aon M. A., 1997, DYNAMIC BIOL ORG FUN
[3] Aon MA, 1996, J CELL BIOCHEM, V60, P271, DOI 10.1002/(SICI)1097-4644(19960201)60:2<271::AID-JCB11>3.0.CO
[4] 2-Q
[5] AON MA, 1996, MODELS CYTOPLASMIC S, P195
[6] AON MA, 1998, UNPUB CELL BIOL INT
[7] BROOKS SPJ, 1992, BIOTECHNIQUES, V13, P906
[8] CASATI DFG, 1998, IN PRESS P 11 INT C
[9] CHARNG YY, 1994, J BIOL CHEM, V269, P24107
[10] MOLECULAR-CLONING AND EXPRESSION OF THE GENE ENCODING ADP-GLUCOSE PYROPHOSPHORYLASE FROM THE CYANOBACTERIUM ANABAENA-SP STRAIN PCC7120
CHARNG, YY
KAKEFUDA, G
IGLESIAS, AA
BUIKEMA, WJ
PREISS, J
[J]. PLANT MOLECULAR BIOLOGY, 1992, 20 (01) : 37 - 47

← 1 2 3 →