Alderwick

Alison M. Smith

Arias

Ball

Birte Svensson

Boos

Cantarel

Cheng

Chia

Christian Ruzanski

Ciucanu

Critchley

Darrell Cockburn

Deschamps

Dippel

Fettke

Gillespie

Henriette L. Pedersen

Julia Smirnova

Kartal

Lengsfeld

Lloyd

Malinova

Marilyn Pike

Martin Rejzek

Martin Steup

Mason

Moller

Oliver Ebenhöh

Oxley

Palmer

Park

Pedersen

Pereira

Robert A. Field

Schupp

Smith

Steichen

Sørensen

William G.T. Willats

Zeeman

Journal of Biological Chemistry

PubMed

Crossref

A Bacterial Glucanotransferase Can Replace the Complex Maltose Metabolism Required for Starch to Sucrose Conversion in Leaves at Night

Controlled conversion of leaf starch to sucrose at night is essential for the normal growth of Arabidopsis. The conversion involves the cytosolic metabolism of maltose to hexose phosphates via an unusual, multidomain protein with 4-glucanotransferase activity, DPE2, believed to transfer glucosyl moieties to a complex heteroglycan prior to their conversion to hexose phosphate via a cytosolic phosphorylase. The significance of this complex pathway is unclear; conversion of maltose to hexose phosphate in bacteria proceeds via a more typical 4-glucanotransferase that does not require a heteroglycan acceptor. It has recently been suggested that DPE2 generates a heterogeneous series of terminal glucan chains on the heteroglycan that acts as a "glucosyl buffer" to ensure a constant rate of sucrose synthesis in the leaf at night. Alternatively, DPE2 and/or the heteroglycan may have specific properties important for their function in the plant. To distinguish between these ideas, we compared the properties of DPE2 with those of the Escherichia coli glucanotransferase MalQ. We found that MalQ cannot use the plant heteroglycan as an acceptor for glucosyl transfer. However, experimental and modeling approaches suggested that it can potentially generate a glucosyl buffer between maltose and hexose phosphate because, unlike DPE2, it can generate polydisperse malto-oligosaccharides from maltose. Consistent with this suggestion, MalQ is capable of restoring an essentially wild-type phenotype when expressed in mutant Arabidopsis plants lacking DPE2. In light of these findings, we discuss the possible evolutionary origins of the complex DPE2-heteroglycan pathway

Ruzanski, C

Smirnova, J

Rejzek, M

Cockburn, D

Pedersen, HL

Pike, M

Willats, WG

Svensson, B

Steup, M

Ebenhöh, O

Smith, AM

Field, RA

The University of Manchester - Institutional Repository

A bacterial glucanotransferase can replace the complex maltose metabolism required for starch to sucrose conversion in leaves at night.

Controlled conversion of leaf starch to sucrose at night is essential for the normal growth of Arabidopsis. The conversion involves the cytosolic metabolism of maltose to hexose phosphates via an unusual, multidomain protein with 4-glucanotransferase activity, DPE2, believed to transfer glucosyl moieties to a complex heteroglycan prior to their conversion to hexose phosphate via a cytosolic phosphorylase. The significance of this complex pathway is unclear; conversion of maltose to hexose phosphate in bacteria proceeds via a more typical 4-glucanotransferase that does not require a heteroglycan acceptor. It has recently been suggested that DPE2 generates a heterogeneous series of terminal glucan chains on the heteroglycan that acts as a “glucosyl buffer” to ensure a constant rate of sucrose synthesis in the leaf at night. Alternatively, DPE2 and/or the heteroglycan may have specific properties important for their function in the plant. To distinguish between these ideas, we compared the properties of DPE2 with those of the Escherichia coli glucanotransferase MalQ. We found that MalQ cannot use the plant heteroglycan as an acceptor for glucosyl transfer. However, experimental and modeling approaches suggested that it can potentially generate a glucosyl buffer between maltose and hexose phosphate because, unlike DPE2, it can generate polydisperse malto-oligosaccharides from maltose. Consistent with this suggestion, MalQ is capable of restoring an essentially wild-type phenotype when expressed in mutant Arabidopsis plants lacking DPE2. In light of these findings, we discuss the possible evolutionary origins of the complex DPE2-heteroglycan pathway

Ruzanski, Christian

Smirnova, Julia

Rejzek, Martin

Cockburn, Darrell

Pedersen, Henriette L.

Pike, Marilyn

Willats, William George Tycho

Svensson, Birte

Steup, Martin

Ebenhöh, Oliver

Smith, Alison M.

Field, Robert A.

Online Research Database In Technology

Pedersen, Henriette L

Willats, William G T

Ebenhoeh, Oliver

Smith, Alison M

Field, Robert A

Aberdeen University Research

English

A critical role for disproportionating enzyme in starch breakdown is revealed by a knock-out mutation in Arabidopsis. Plant

Alterations in cytosolic glucose-phosphate metabolism affect structural features and biochemical properties of starch-related heteroglycans.

Early gene duplication within Chloroplastida and its correspondence with relocation of starch metabolism to chloroplasts.

Eukaryotic starch degradation: integration of plastidial and cytosolic pathways.

Identification, subcellular localization, and biochemical characterization of water-soluble heteroglycans (SHG) in leaves of Arabidopsis thaliana L. Distinct SHG reside in the cytosol and in the apoplast.

Metabolic symbiosis and the birth of the plant kingdom.

P.,andSteup,M.(2005)Analysisofcytosolicheteroglycansfromleavesof transgenic potato (Solanum tuberosum L.) plants that under- or overexpressthePho2phosphorylaseisozyme.PlantCellPhysiol.46,1987–2004 10.

Role of maltose enzymes in glycogen synthesis by Escherichia coli.

Starch in the Arabidopsis plant. Starch-Sta ¨rke 61,

Starch. Its metabolism, evolution, and biotechnological modification in plants.

The maltodextrin system of Escherichia coli.

The relocation of starch metabolism to

A bacterial glucanotransferase can replace the complex maltose metabolism required for starch to sucrose conversion in leaves at night

http://dx.doi.org/10.1074/jbc.M113.497867

A Bacterial Glucanotransferase Can Replace the Complex Maltose Metabolism Required for Starch to Sucrose Conversion in Leaves at Night

Abstract

Similar works

Full text

Available Versions

Crossref

The University of Manchester - Institutional Repository

Online Research Database In Technology

Aberdeen University Research