The role of conserved non-aromatic residues in the Lactobacillus amylovorus α-amylase CBM26-starch interaction
| Autor: | Silvia Moreno-Mendieta, Nancy O. Pulido, Amelia Farrés, Sergio Sánchez, Romina Rodríguez-Sanoja, Zaira Sánchez-Cuapio, Karen Manoutcharian, Silvia Armenta, Alejandra Hernández-Santoyo, Maria Elena Munguia |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Starch
02 engineering and technology Biochemistry 03 medical and health sciences chemistry.chemical_compound Residue (chemistry) Protein Domains Structural Biology Aromatic amino acids Point Mutation Amylase Amino Acid Sequence Molecular Biology Protein secondary structure Glucans Conserved Sequence 030304 developmental biology 0303 health sciences Binding Sites biology Sequence Homology Amino Acid Chemistry Point mutation General Medicine 021001 nanoscience & nanotechnology Glutamine Lactobacillus acidophilus Mutagenesis biology.protein Carbohydrate-binding module alpha-Amylases 0210 nano-technology Protein Binding |
| Zdroj: | International journal of biological macromolecules. 121 |
| ISSN: | 1879-0003 |
| Popis: | It is generally accepted that carbohydrate binding modules (CBMs) recognize their carbohydrate ligands by hydrophobic and CH-π interactions. Point mutations of one CBM26 of the Lactobacillus amylovorus α-amylase starch-binding domain (LaCBM26) showed that conserved non-aromatic residue are essential in the starch recognition function of the domain, as the mutation of a single glutamine (Q68L) eliminates binding to starch and β-cyclodextrin, even in the presence of aromatic amino acids necessary for ligand binding. The secondary structure of mutated proteins was verified and showed no differences from the wild-type domain. However, random mutations of five residues involved in binding (Y18, Y20, Q68, E74, and F77) did cause change in the secondary structure of the protein, which also causes loss of function. Much of the diversity introduced in the LaCBM26 was probably incompatible with the appropriate folding of these proteins, suggesting that the domain has little tolerance to change. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect