9 7 g 4
Home About us MoEF Contact us Sitemap Tamil Website  
About Envis
Whats New
Research on Microbes
Microbiology Experts
Online Submission
Access Statistics

Site Visitors

blog tracking

Biochemistry and Biophysics Reports
Volume 14, 2018, Pages 35-42

Isolation, identification and in silico analysis of alpha-amylase gene of Aspergillus niger strain CSA35 obtained from cassava undergoing spoilage

Oghenetega J.Avwiorokoa, Akpovwehwee A.Anigborob, Nnanna N.Unachukwuc, Nyerhovwo J.Tonukarib

Biochemistry Division, Department of Chemical Sciences, College of Natural Sciences, Redeemer's University, Ede, Osun State, Nigeria.


In this investigation, a gene (CDF_Amyl) encoding extracellular α-amylase in Aspergillus niger strain CSA35 associated with cassava spoilage was amplified using specific primers and characterized in silico. The gene had a partial nucleotide sequence of 968 bp and encoded a protein of 222 aa residues with a molecular weight and isoelectric point of 25.13 kDa and 4.17, respectively. Its catalytic site was located in the active site domain. BLASTp analysis showed that the protein primary sequence of the α-amylase gene had 98% and 99% homologies with the α-amylase of A. niger and A. oryzae RIB40, respectively. The gene is more closely related to α-amylase genes from fungi than to bacterial, plant, or animal α-amylase genes. Restriction mapping of the gene showed it can be digested with restriction enzymes like NcoI, PstI, SmaI, and BcLI among others but not with EcoRI and EcoRV. Its protein product had a hydrophobicity score of − 0.43 but no transmembrane helix. The CDF_Amyl protein was subcellularly localized in the secretory pathway, an indication of its release into extracellular space after secretion. Also, the 3D structure of the CDF-Amyl protein was barrel-shaped with domains characteristic of α-amylases. The encoded α-amylase Vmax is 6.90 U/mg protein and Km is 6.70 mg/ml. It was concluded that the unique characteristics of the CDF_Amyl gene and its deduced protein could find applications in biotechnological, food and pharmaceutical industries where cloning and further modification of this gene would be required for product development and improvement.

Keywords: Aspergillus niger, Alpha-amylase gene, Bioinformatics characterisation, Restriction enzymes, Phylogenetics, evolution.

Copyright © 2005 ENVIS Centre ! All rights reserved
This site is optimized for 1024 x 768 screen resolution