Electrostatic channeling between citrate synthase ics and malate dehydrogenase (MDH) fusion proteins

K. Shatalin, I. Morgunov, P. Srere

Research output: Contribution to journalArticle

Abstract

The enzymes of the Krebs TCA cycle may form a multienzyme complex, creating channels through which substrates and intermediates may be transported between enzymes. To test this model, we constructed two fusion proteins containing yeast mitochondrial CS (CS1) and MDH (MDH1) moieties. In both fusion proteins the C terminus of CS1 is connected to the Ntenninus of MDH 1 either by a linker of 3 or 10 a.a. These fusion proteins show channeling activity in competition reactions not shown by a mixture of free CS1 and MDH1. These results confirm a recent model of electrostatic interactions of these enzymes (Elcock tk McCammon, Biochem, 1996)and an earlier prediction trom this laboratory (Lindbladh rl at. Bincheni 1994). The model predicts the formation of an electropositive channel for transport oi'the intermediate oxalacetate from the active site of one enzyme to the active site oi another. To test this hypothesis we studied the influence oi ionic strength on the function of fusion proteins in a <ompetition reaction. An increase in ionic strength results in the decrease of channeling activity of fusion proteins in competition reactions to the level of activity of a mixture of free enzymes. Thus, high ionic strength caused the disruption of the channel. These observations support the model of formation of an electrostatic channel which can transport intermediate substrates from one enzyme active site to another.

Original languageEnglish
JournalFASEB Journal
Volume11
Issue number9
Publication statusPublished - 1997

Fingerprint

Citrate (si)-Synthase
Malate Dehydrogenase
citrate (si)-synthase
malate dehydrogenase
Static Electricity
Electrostatics
Fusion reactions
Enzymes
ionic strength
enzymes
Ionic strength
active sites
Osmolar Concentration
Catalytic Domain
Proteins
proteins
multienzyme complexes
Multienzyme Complexes
Fungal Proteins
Citric Acid Cycle

ASJC Scopus subject areas

  • Agricultural and Biological Sciences (miscellaneous)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Biochemistry
  • Cell Biology

Cite this

Electrostatic channeling between citrate synthase ics and malate dehydrogenase (MDH) fusion proteins. / Shatalin, K.; Morgunov, I.; Srere, P.

In: FASEB Journal, Vol. 11, No. 9, 1997.

Research output: Contribution to journalArticle

@article{deeb5a1f80224fa7b19e9deedc81a9a6,
title = "Electrostatic channeling between citrate synthase ics and malate dehydrogenase (MDH) fusion proteins",
abstract = "The enzymes of the Krebs TCA cycle may form a multienzyme complex, creating channels through which substrates and intermediates may be transported between enzymes. To test this model, we constructed two fusion proteins containing yeast mitochondrial CS (CS1) and MDH (MDH1) moieties. In both fusion proteins the C terminus of CS1 is connected to the Ntenninus of MDH 1 either by a linker of 3 or 10 a.a. These fusion proteins show channeling activity in competition reactions not shown by a mixture of free CS1 and MDH1. These results confirm a recent model of electrostatic interactions of these enzymes (Elcock tk McCammon, Biochem, 1996)and an earlier prediction trom this laboratory (Lindbladh rl at. Bincheni 1994). The model predicts the formation of an electropositive channel for transport oi'the intermediate oxalacetate from the active site of one enzyme to the active site oi another. To test this hypothesis we studied the influence oi ionic strength on the function of fusion proteins in a",
author = "K. Shatalin and I. Morgunov and P. Srere",
year = "1997",
language = "English",
volume = "11",
journal = "FASEB Journal",
issn = "0892-6638",
publisher = "FASEB",
number = "9",

}

TY - JOUR

T1 - Electrostatic channeling between citrate synthase ics and malate dehydrogenase (MDH) fusion proteins

AU - Shatalin, K.

AU - Morgunov, I.

AU - Srere, P.

PY - 1997

Y1 - 1997

N2 - The enzymes of the Krebs TCA cycle may form a multienzyme complex, creating channels through which substrates and intermediates may be transported between enzymes. To test this model, we constructed two fusion proteins containing yeast mitochondrial CS (CS1) and MDH (MDH1) moieties. In both fusion proteins the C terminus of CS1 is connected to the Ntenninus of MDH 1 either by a linker of 3 or 10 a.a. These fusion proteins show channeling activity in competition reactions not shown by a mixture of free CS1 and MDH1. These results confirm a recent model of electrostatic interactions of these enzymes (Elcock tk McCammon, Biochem, 1996)and an earlier prediction trom this laboratory (Lindbladh rl at. Bincheni 1994). The model predicts the formation of an electropositive channel for transport oi'the intermediate oxalacetate from the active site of one enzyme to the active site oi another. To test this hypothesis we studied the influence oi ionic strength on the function of fusion proteins in a

AB - The enzymes of the Krebs TCA cycle may form a multienzyme complex, creating channels through which substrates and intermediates may be transported between enzymes. To test this model, we constructed two fusion proteins containing yeast mitochondrial CS (CS1) and MDH (MDH1) moieties. In both fusion proteins the C terminus of CS1 is connected to the Ntenninus of MDH 1 either by a linker of 3 or 10 a.a. These fusion proteins show channeling activity in competition reactions not shown by a mixture of free CS1 and MDH1. These results confirm a recent model of electrostatic interactions of these enzymes (Elcock tk McCammon, Biochem, 1996)and an earlier prediction trom this laboratory (Lindbladh rl at. Bincheni 1994). The model predicts the formation of an electropositive channel for transport oi'the intermediate oxalacetate from the active site of one enzyme to the active site oi another. To test this hypothesis we studied the influence oi ionic strength on the function of fusion proteins in a

UR - http://www.scopus.com/inward/record.url?scp=33750154391&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33750154391&partnerID=8YFLogxK

M3 - Article

VL - 11

JO - FASEB Journal

JF - FASEB Journal

SN - 0892-6638

IS - 9

ER -