Interaction of spinach leaf adenosine diphosphate glucose α-1,4-glucan α-4-glucosyl transferase and α-1,4-glucan, α-1,4-glucan-6-glycosyl transferase in synthesis of branched α-glucan

Hawker, J. S.; Ozbun, J. L.; Ozaki, Hachiro; Greenberg, Elaine; Preiss, Jack

doi:10.1016/0003-9861(74)90430-5

Cited by 195 publications

(99 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In cereals, the SBEII class is subdivided into two distinct gene products, SBEIIa and SBEIIb, each with different kinetic characteristics and tissue expression patterns. SBEII isoforms transfer shorter chains (DP [6][7][8][9][10][11][12][13][14] and prefer amylopectin as a substrate (29). These characteristics have also been shown in a variety of other plant species, for example, rice (Oryza sativa L.; ref.…”

Section: Mode Of Action and Properties Of Sbesmentioning

confidence: 83%

“…In addition, SS activity can be stimulated in the presence of SBEs, particularly when there is no added primer (see ref. 6, and references therein). SBEs are catalytically active as monomeric proteins.…”

Section: Mode Of Action and Properties Of Sbesmentioning

confidence: 99%

“…Citrate can activate SS activity, by lowering the K m for the a-glucan primer, and can stimulate both spinach leaf (Spinacia oleracea L.) and bean (Phaseolus vulgaris) SBEs (6,26). The activity of a number of starch biosynthetic enzymes has been shown to be modified by redox state, and activities of Arabidopsis SBE 2.1 and 2.2 were enhanced under reducing conditions (10).…”

Section: Figmentioning

confidence: 99%

See 2 more Smart Citations

A review of starch‐branching enzymes and their role in amylopectin biosynthesis

2014

View full text Add to dashboard Cite

Starch-branching enzymes (SBEs) are one of the four major enzyme classes involved in starch biosynthesis in plants and algae, and their activities play a crucial role in determining the structure and physical properties of starch granules. SBEs generate a-1,6-branch linkages in a-glucans through cleavage of internal a-1,4 bonds and transfer of the released reducing ends to C-6 hydroxyls. Starch biosynthesis in plants and algae requires multiple isoforms of SBEs and is distinct from glycogen biosynthesis in both prokaryotes and eukaryotes which uses a single branching enzyme (BE) isoform. One of the unique characteristics of starch structure is the grouping of a-1,6-branch points in clusters within amylopectin. This is a feature of SBEs and their interplay with other starch biosynthetic enzymes, thus facilitating formation of the compact water-insoluble semicrystalline starch granule. In this respect, the activity of SBE isoforms is pivotal in starch granule assembly. SBEs are structurally related to the aamylase superfamily of enzymes, sharing three domains of secondary structure with prokaryotic Bes: the central (b/a) 8 -barrel catalytic domain, an NH 2 -terminal domain involved in determining the size of a-glucan chain transferred, and the C-terminal domain responsible for catalytic capacity and substrate preference. In addition, SBEs have conserved plant-specific domains, including phosphorylation sites which are thought to be involved in regulating starch metabolism. SBEs form heteromeric protein complexes with other SBE isoforms as well as other enzymes involved in starch synthesis, and assembly of these protein complexes is regulated by protein phosphorylation. Phosphorylated SBEIIb is found in multienzyme complexes with isoforms of glucan-elongating starch synthases, and these protein complexes are implicated in amylopectin cluster formation. This review presents a comparative overview of plant SBEs and includes a review of their properties, structural and functional characteristics, and recent developments on their posttranslational regulation.

show abstract

Section: Mode Of Action and Properties Of Sbesmentioning

confidence: 83%

Section: Mode Of Action and Properties Of Sbesmentioning

confidence: 99%

Section: Figmentioning

confidence: 99%

See 1 more Smart Citation

A review of starch‐branching enzymes and their role in amylopectin biosynthesis

2014

View full text Add to dashboard Cite

show abstract

“…Isoforms of SBE have been purified from leaves of spinach [2], maize endosperm [3], sorghum seeds [4], developing embryo of pea [5] and developing rice endosperm 161. Differences in the catalytic properties between the SBE isoforms from pea [5] as well as from maize [7] have been reported.…”

Section: N-terminal Sequencing Of Sbementioning

confidence: 99%

Characterization of the 97 and 103 kDa forms of starch branching enzyme from potato tubers

Khoshnoodi

Rask

et al. 1993

FEBS Letters

View full text Add to dashboard Cite

Terminal analysis, peptide mapping and partial peptide sequencing of the 97 and 103 kDa forms of starch branching enzyme from potato tubers showed that the two forms are highly related. A comparison with sequence data in the literature showed that these forms belong to the starch branching enzyme isofonn I family. An internal cDNA fragment was obtained using PCR technology on potato tuber RNA with two oligonucleotide primers constructed from the peptide sequence data. Southern blot analysis using the PCR fragment as probe showed that there is only one gene locus encoding this isofonn of the enzyme in Solarturn tuberosum as well as in Solanum commersonii.

show abstract

“…16 23) In past BE investigations, the activity has been assayed mainly using three methods 18,24) ; Firstly, the phosphorylase a stimulation assay, which is based on the extent of stimulation of the activity of rabbit muscle phosphorylase a by BE, 18 24) secondly, the iodine stain assay, which is based on monitoring the decrease in absorbance of the glucan iodine complex catalyzed with the addition of BE, 24,25) and thirdly, the branching linkage assay (BL assay) based on the direct measurement of number of branched linkages introduced in glucan substrate by BE. 17) Although the phosphorylase a stimulation assay and the iodine stain assay have been most conventionally used, these methods are basically non quantitative.…”

mentioning

confidence: 99%

Quantitative Assay Method for Starch Branching Enzyme with Bicinchoninic Acid by Measuring the Reducing Terminals of Glucans

Utsumi¹,

Yoshida²,

Francisco³

et al. 2009

J. Appl. Glycosci.

View full text Add to dashboard Cite

Starch is a glucose polymer with two α glucosidic linkages, and linearly linked α 1,4 glucosidic chains are branched by α 1,6 glucosidic linkages. Starch is composed of linear or fewly branched amylose and highly branched amylopectin. Amylopectin has a distinct highly ordered structure called "tandem cluster structure", in which most side chains are arranged in parallel and pairs of neighboring chains form double helices 1) when linear portions of these chains reach the length equivalent to degree of polymerization (DP) > 10. 2 5) The formation of double helices in the amylopectin cluster dramatically induces its hydrophobicity and crystallinity. These specific features of amylopectin fine structure are enabled by the localization of position of branches in the cluster. 6) The starch synthesis system has developed during the process of evolution of plants, 6,7) and key enzymes involved in the construction of amylopectin tandem cluster structure have differentiated into multiple isozymes with distinct functions whereas in glycogen synthesizing organisms such as bacteria and animals no such functional differentiations in glycogen synthesis enzymes have occurred. 8,9) Starch branching enzyme (BE) plays an important part in the formation of branches in amylopectin molecules. Green plants are known to have two types of BE isozymes, BEI and BEII. In addition, BEII is further differentiated into BEIIa and BEIIb isoforms in cereals although BEIIb is usually specifically expressed in endosperm while BEIIa is ubiquitously present in every tissue. 10 13) Our biochemical studies on three mutants of rice which are defective in BEI, BEIIa and BEIIb, respectively, strongly suggest that the role of BEIlb is most specific in synthesizing branches located on the basal portion of the crystal zone (referred to as the crystal lamellae) of the cluster because BEI and BEIIa can hardly complement its role in its absence. 8,14) On the other hand, BEI plays an important part in forming branches which are positioned at the basal part of the cluster in the less crystalline zone (referred to as the amorphous lamellae), and those which link the clusters, but its role can be largely complemented by BEIIb and BEIIa in the BEI mutant. 15) Although the activity of BEIIa accounts for about 20% of the total BE activity in rice endosperm, the specificity of its function must be poor because no significant changes in the structure of amylopectin or the physicochemical properties of starch granules are found in the BEIIa mutant (Nishi et al ., unpublished data).In vitro studies using purified BE isozymes revealed that BEI and BEII differ in terms of specificity for glucans, amylose or amylopectin, and the length of glucan chains transferred; BEI prefers to attack amylose to amlopectin and preferentially transfers various glucan chains with DP values greater than 6, whereas BEII prefers to use amylopectin to amylose, and preferentially transfers short chains with DP6 in addition to DP7. 16 23) In past BE investigations, the activity has been assaye...

show abstract

Interaction of spinach leaf adenosine diphosphate glucose α-1,4-glucan α-4-glucosyl transferase and α-1,4-glucan, α-1,4-glucan-6-glycosyl transferase in synthesis of branched α-glucan

Cited by 195 publications

References 35 publications

A review of starch‐branching enzymes and their role in amylopectin biosynthesis

A review of starch‐branching enzymes and their role in amylopectin biosynthesis

Characterization of the 97 and 103 kDa forms of starch branching enzyme from potato tubers

Quantitative Assay Method for Starch Branching Enzyme with Bicinchoninic Acid by Measuring the Reducing Terminals of Glucans

Contact Info

Product

Resources

About