Microbial degradation of myo-inositol hexakisphosphate (IP6): specificity, kinetics, and simulation

Abstract

Microbial degradation of -inositol hexakisphosphate (IP6) is crucial to deal with nutritional problems in monogastric animals as well as to prevent environmental phosphate pollution. The present study deals with the degradation of IP6 by microorganisms such as spp. and. These microbes were screened for phytase production under laboratory conditions. The specificity of the enzyme was tested for various phosphorylated substrates such as sodium phytate (IP6), sodium hexametaphosphate, phenyl phosphate, α-d-glucose-6 phosphate, inosine 5' monophosphate and pyridoxal 5' phosphate. These enzymes were highly specific to IP6. The influence of modulators such as phytochemicals and metal ions on the enzymatic activity was assessed. These modulators in different concentrations had varying effect on microbial phytases. Calcium (in optimal concentration of 0.5 M) played an important role in enzyme activation. The enzymes were then characterized based on their molecular weight 41~43 kDa. The phytase-producing microbes were assessed for IP6 degradation in a simulated intestinal setup. Among the selected microbes, hydrolyzed IP6 effectively, as confirmed by colorimetric time-based analysis.

Characterization of a putative metal-dependent PTP-like phosphatase from Lactobacillus helveticus 2126

“…Phytate induced the production of extracellular phytase within 24 h of incubation in the present study. A similar result was obtained for other bacterial phytases reported in Priyodip and Balaji ( 2018 ). However, most of the bacterial phytase activities reported to date were observed after a longer incubation.…”

“…This was proved by the lowest Michaelis-Menten constant (K m ) value of 299.50 ± 4.95 μM in comparison with 320.54 ± 12.03 μM obtained for sodium hexametaphosphate, 2011.89 ± 123.85 μM for phenyl phosphate, 875.19 ± 82.77 μM for α-D-glucose-6 phosphate, 343.02±10.06 μM for Inosine 5′ monophosphate, and 1124.39 ± 77.01 μM for pyridoxal 5′ phosphate. Similar phytate-specific bacterial phytases were reported for Bacillus subtilis with K m 293 μM (Jain et al 2018 ), Sporosarcina globispora with K m 254.90 ± 8.52 μM (Priyodip and Balaji 2018 ), Bacillus amyloliquefaciens with K m 550 μM (Kim et al 1998 ), Bacillus spp. with K m 50 μM (Choi et al 2001 ), and Escherichia coli with K m 130 μM (Greiner et al 1993 ), respectively.…”

“…The bacterium was grown in a phosphatase screening medium (PSM) (Priyodip and Balaji 2018 ). In this study, phytate was used as the sole carbon source in place of dextrose.…”

Protein composition and nutritional aspects of pea protein fractions obtained by a modified isoelectric precipitation method using fermentation

“…Sumengen et al (109) reported high intra-and extra-cellular phytase activity for L. plantarum. A high phytase activity was also reported for S. thermophilus by Priyodip and Balaji (110,111). However, in the present study, no significant differences were observed between the strains, which could suggest the similar activity of phytase among ST and LP.…”

Lactic Fermentation as a Strategy to Improve the Nutritional and Functional Values of Pseudocereals

“…Recent studies showed that phytate degradation by recombinant probiotic LAB could provide a solution for phosphate utilization in humans (254, 255). Regarding this topic, Vasudevan et al (247) reviewed the contributions of recombinant technology to phytase research during the last decade with specific emphasis on new generation phytases.…”