6GNE

Catalytic domain of Starch Synthase IV from Arabidopsis thaliana bound to ADP and acarbose

Summary for 6GNE

• Entry DOI: 10.2210/pdb6gne/pdb
• Related PRD ID: PRD_900001 PRD_900007
• Descriptor: Probable starch synthase 4, chloroplastic/amyloplastic, 4,6-dideoxy-4-{[(1S,4R,5S,6S)-4,5,6-trihydroxy-3-(hydroxymethyl)cyclohex-2-en-1-yl]amino}-alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose, alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose, ... (5 entities in total)
• Functional Keywords: glycosyl transferase, starch synthase, acarbose, adp, transferase
• Biological source: Arabidopsis thaliana (thale cress)
• Total number of polymer chains: 2
• Total formula weight: 117081.54

Authors

Cuesta-Seijo, J.A.,Ruzanski, C.,Krucewicz, K.,Striebeck, A.,Palcic, M.M. (deposition date: 2018-05-30, release date: 2018-07-25, Last modification date: 2024-01-17)

Primary citation

Nielsen, M.M.,Ruzanski, C.,Krucewicz, K.,Striebeck, A.,Cenci, U.,Ball, S.G.,Palcic, M.M.,Cuesta-Seijo, J.A.
Crystal Structures of theCatalyticDomain ofArabidopsis thalianaStarch Synthase IV, of Granule Bound Starch Synthase From CLg1 and of Granule Bound Starch Synthase I ofCyanophora paradoxaIllustrate Substrate Recognition in Starch Synthases.
Front Plant Sci, 9:1138-1138, 2018

PubMed Abstract: Starch synthases (SSs) are responsible for depositing the majority of glucoses in starch. Structural knowledge on these enzymes that is available from the crystal structures of rice granule bound starch synthase (GBSS) and barley SSI provides incomplete information on substrate binding and active site architecture. Here we report the crystal structures of the catalytic domains of SSIV from , of GBSS from the cyanobacterium CLg1 and GBSSI from the glaucophyte , with all three bound to ADP and the inhibitor acarbose. The SSIV structure illustrates in detail the modes of binding for both donor and acceptor in a plant SS. CLg1GBSS contains, in the same crystal structure, examples of molecules with and without bound acceptor, which illustrates the conformational changes induced upon acceptor binding that presumably precede catalytic activity. With structures available from several isoforms of plant and non-plant SSs, as well as the closely related bacterial glycogen synthases, we analyze, at the structural level, the common elements that define a SS, the elements that are necessary for substrate binding and singularities of the GBSS family that could underlie its processivity. While the phylogeny of the SSIII/IV/V has been recently discussed, we now further report the detailed evolutionary history of the GBSS/SSI/SSII type of SSs enlightening the origin of the GBSS enzymes used in our structural analysis.

PubMed: 30123236
DOI: 10.3389/fpls.2018.01138

Experimental method

X-RAY DIFFRACTION (2.55 Å)