Functional demonstrations of starch binding domains present in Ostreococcus tauri starch synthases isoforms

Barchiesi, Julieta; Hedín, Nicolás; Gómez-Casati, Diego F.; Ballícora, Miguel A.; Busi, María V.

doi:10.1186/s13104-015-1598-6

Cited by 15 publications

(24 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Three SS subfamilies were reported in O. tauri consisting of one SSI, one SSII and three SSIIIs isoforms; all of them remaining uncharacterized to date. The conservation throughout the evolution of the three SSIII isoforms and the absence of an SSIV isoform could be related to the presence of a single starch granule in this alga, which has similar composition that those starch granules found in higher plants but with a particular partitioning and propagation mechanism [6,7]. In plants, the N-terminal region of the SSIII isoform contains three in tandem starch binding domains (SBDs), belonging to the carbohydrate binding module 53 (CBM53) family [3,8].…”

Section: Introductionmentioning

confidence: 91%

“…reinhardtii [8,28,29]. As mentioned above, C. reinhardtii presents two starch synthases III [30], containing two and three SBDs [6], that are structurally more similar to OsttaSSIII-A, OsttaSSIII-B, and ArathSSIII rather than OsttaSSIII-C. However, to date, only one C.…”

Section: Kinetic Characterization Of Osttassiii-cmentioning

confidence: 99%

“…We have previously shown that SSIII isoforms from algae present a variable number of SBDs in their N-terminal region [6]. The model green algae Chlamydomonas reinhardtii for example, presents two SSIII isoforms, containing two and three SBDs respectively.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Identification of a novel starch synthase III from the picoalgae Ostreococcus tauri

et al. 2017

Self Cite

View full text Add to dashboard Cite

Hydrosoluble glycogen is the major energy storage compound in bacteria, archaea, fungi, and animal cells. In contrast, photosynthetic eukaryotes have evolved to build a highly organized semicrystalline granule of starch. Several enzymes are involved in polysaccharide synthesis, among which glycogen or starch synthase catalyze the elongation of the α-1,4-glucan chain. Ostreococcus tauri, accumulates a single starch granule and contains three starch synthase III (SSIII) isoforms, known as OsttaSSIII-A, OsttaSSIII-B and OsttaSSIII-C. After amino acids sequence analysis we found that OsttaSSIII-C lacks starch-binding domains, being 49% identical to the catalytic region of the SSIII from Arabidopsis thaliana and 32% identical to the entire Escherichia coli glycogen synthase. The recombinant, highly purified OsttaSSIII-C exhibited preference to use as a primer branched glycans (such as rabbit muscle glycogen and amylopectin), rather than amylose. Also, the enzyme displayed a high affinity toward ADP-glucose. We found a marked conservation of the amino acids located in the catalytic site, and specifically determined the role of residues R270, K275 and E352 by site-directed mutagenesis. Results show that these residues are important for OsttaSSIII-C activity, suggesting a strong similarity between the active site of the O. tauri SSIII-C isoform and other bacterial glycogen synthases.

show abstract

Section: Introductionmentioning

confidence: 91%

Section: Kinetic Characterization Of Osttassiii-cmentioning

confidence: 99%

See 1 more Smart Citation

Identification of a novel starch synthase III from the picoalgae Ostreococcus tauri

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…Fig. (3A) shows in magenta the position of this putative CBM from OsttaISA1, and it can be clearly observed that it comprises six ß-strands forming the classical CBM ß-sandwich folding [27,29]. The central part of the protein is composed of the Catalytic Domain (CD), which is also conserved among the α-amylase family, and belongs to the family 13 of glycoside hydrolase from the CAZY database [51,61].…”

Section: Homology Modeling Of Osttaisa1mentioning

confidence: 99%

Functional and Structural Characterization of a Novel Isoamylase from Ostreococcus tauri and Role of the N-Terminal Domain

Hedín¹,

Barchiesi²,

Gómez-Casati³

et al. 2020

TOBIOTJ

Self Cite

View full text Add to dashboard Cite

Background: The debranching starch enzymes, isoamylase 1 and 2 are well-conserved enzymes present in almost all the photosynthetic organisms. These enzymes are involved in the crystallization process of starch and are key components which remove misplaced α-1,6 ramifications on the final molecule. Aim: In this work, we performed a functional and structural study of a novel isoamylase from Ostreococcus tauri. Methods: We identified conserved amino acid residues possibly involved in catalysis. We also identified a region at the N-terminal end that resembles a Carbohydrate Binding Domain (CBM), which is more related to the family CBM48, but has no spatial conservation of the residues involved in carbohydrate binding. Results: The cloning, expression and biochemical characterization of this N-terminal region confirmed that it binds to polysaccharides, showing greater capacity for binding to amylopectin rather than total starch or amylose. Conclusion: This module could be a variant of the CBM48 family or it could be classified within a new CBM family.

show abstract

“…Among CBMs, we can highlight the Starch Binding Domains (SBDs), which have acquired the evolutionary advantage of being capable of disrupting the surface of their substrate due to the presence of two binding sites [26][27][28]. These domains are distributed in twelve CBM families; 20,21,25,26,34,41,45,48,53,58, 68 and 69 and they are found in archaea, bacteria, and eukaryotes [29] (http://www.cazy.org/).…”

Section: Introductionmentioning

confidence: 99%

Identification and characterization of a novel starch branching enzyme from the picoalgae Ostreococcus tauri

Hedín

Barchiesi

Gómez-Casati

et al. 2017

Archives of Biochemistry and Biophysics

Self Cite

View full text Add to dashboard Cite

Starch branching enzyme is a highly conserved protein from plants to algae. This enzyme participates in starch granule assembly by the addition of α-1,6-glucan branches to the α-1,4-polyglucans. This modification determines the structure of amylopectin thus arranging the final composition of the starch granule. Herein, we describe the function of the Ot01g03030 gene from the picoalgae Ostreococcus tauri. Although in silico analysis suggested that this gene codes for a starch debranching enzyme, our biochemical studies support that this gene encodes a branching enzyme (BE). The resulting 1058 amino acids protein has two in tandem carbohydrate binding domains (CBMs, from the CBM41 and CBM48 families) at the N-terminal (residues 64-403) followed by the C-terminal catalytic domain (residues 426-1058). Analysis of the BE truncated isoforms show that the CBMs bind differentially to whole starch, amylose or amylopectin. Furthermore, both CBMs seem to be essential for BE activity, as no catalytic activity was detected in the truncated enzyme comprising only by the catalytic domain. Our results suggest that the Ot01g03030 gene codifies for a functional BE containing two CBMs from CBM41 and CBM48 families which are critical for enzyme function and regulation.

show abstract

Functional demonstrations of starch binding domains present in Ostreococcus tauri starch synthases isoforms

Cited by 15 publications

References 63 publications

Identification of a novel starch synthase III from the picoalgae Ostreococcus tauri

Identification of a novel starch synthase III from the picoalgae Ostreococcus tauri

Functional and Structural Characterization of a Novel Isoamylase from Ostreococcus tauri and Role of the N-Terminal Domain

Identification and characterization of a novel starch branching enzyme from the picoalgae Ostreococcus tauri

Contact Info

Product

Resources

About