Production, Characterization, and Molecular Phylogenetic Analysis of Phytase from Aspergillus niger Isolates of an Indonesia Origin

Abstract

This research aimed at analyzing the phytase from fungal isolates SB1, SB2, BS, and WF produced in cornstarch with glucose medium (CS+Glu) as carbon sources and Potatoes dextrose broth (PDB). The activity of phytase from isolates SB1, SB2, BS, and WF produced in CS+Glu medium was 2.97 UmL^-1, 2.87 UmL^-1, 3.18 UmL^-1, and 4.37 UmL^-1, respectively, while the activity of phytases was 2.07 UmL^-1, 2.17 UmL^-1, 2.22 UmL^-1, and 2.78 UmL^-1 respectively in PDB medium. The optimal temperature of SB1 and WF phytase was 40°C, while SB2 and BS were 50°C and 60°C, respectively. The optimal pH of SB1 and WF phytase was 5.0, while SB2 and BS phytase were 6.0, and 4.0 respectively. 18S rRNA gene analysis revealed that SB1 was 99% identical to Aspergillus niger ANTS (KY825168.1), SB2, BS, and WF were 99% identical to A. niger Moriga leaf (MG889596.1). Multiple sequences and phylogenetic analysis of phytase gene showed that phyA_SB1 and phyA_SB2 were 98% homology with A. ficuum (AAB26466), 97% with A. niger (ADP05107) while phyA_WF was 99% with A. ochraceoroseus (PLB29348), 98% with A. niger (ADP05105). The deduced proteins contain conserved motifs RHGARYPTD at N-terminal while lacking HD motif at C-terminal. These phytases were in the same cluster with Aspergillus sp. phytase A indicating that they belong to Histidine Acid Phosphatases (HAP) family.