RESEARCH ARTICLE

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

The Open Biotechnology Journal 12 Feb 2020 RESEARCH ARTICLE DOI: 10.2174/1874070702014010001

Abstract

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.

Keywords: Carbohydrate Binding Domain (CBM), Debranching starch enzymes, Amino acid residues, Polysaccharides, Biochemical characterization, Carbohydrates.
Fulltext HTML PDF
1800
1801
1802
1803
1804