Enhanced catalytic activity of Bacillus aryabhattai P1 protease by modulation with nanoactivator

Biocatalytic Profiling of Free and Immobilized Partially Purified Alkaline Protease from an Autochthonous Bacillus aryabhattai Ab15-ES

Partially purified alkaline protease produced by an indigenous bacterial strain, Bacillus aryabhattai Ab15-ES, was insolubilized in alginate beads using an entrapment technique. Maximum entrapped enzyme activities of 68.76% and 71.06% were recorded at optimum conditions of 2% (w/v) sodium alginate and 0.3 M calcium chloride. Biochemical profiling of free and immobilized proteases was investigated by determining their activity and stability as well as kinetic properties. Both enzyme preparations exhibited maximum activity at the optimum pH and temperature of 8.0 and 50 °C, respectively. However, in comparison to the free enzyme, the immobilized protease showed improved pH stability at 8.0–9.0 and thermal stability at 40–50 °C. In addition, the entrapped protease exhibited a higher Vmax and increased affinity to the substrate (1.65-fold) than the soluble enzyme. The immobilized protease was found to be more stable than the free enzyme, retaining 80.88% and 38.37% of its initial activity when stored at 4 °C and 25 °C, respectively, for 30 d. After repeated use seven times, the protease entrapped in alginate beads maintained 32.93% of its original activity. These findings suggest the efficacy and sustainability of the developed immobilized catalytic system for various biotechnological applications.

Isolation and characterization of potential multiple extracellular enzyme-producing bacteria from waste dumping area in Addis Ababa

Extremozymes are innovative and robust biocatalysts produced by various microorganisms from harsh environments. As thermophilic organisms can only develop in a few places, studying them in geothermal environments has provided new insights into the origins and evolution of early life and access to significant bio-resources with potential biotechnology applications. The work aimed to isolate and identify likely multiple extracellular enzyme-producing thermophilic bacteria from an Addis Ababa landfill (Qoshe). The streaking approach was used to purify 102 isolates acquired by serial dilution and spread plate method. The isolates were morphologically and biochemically characterized. Thirty-five cellulases, 22 amylase, 17 protease, and nine lipase-producing bacteria were identified using primary screening methods. Further secondary screening using Strain safety evaluation; two bacterial strains (TQ11 and TQ46) were identified. Based on morphological and biochemical tests, they were found to be gram-positive and rod-shaped. Furthermore, molecular identification and phylogenic analysis of selected promising isolates confirmed the identity of the isolates, Paenibacillus dendritiformis (TQ11) and Anoxybacillus flavithermus (TQ46). The results indicated that, multiple extracellular enzyme-producing thermophilic bacteria isolated from a waste dumping area in Addis Ababa offer useful features for environmental sustainability in a wide range of industrial applications due to their biodegradability and specialized stability under extreme conditions, increased raw material utilization, and decreased waste.

Cloning, Expression and Biochemical Characterization of the Recombinant α-amylase from Bacillus subtilis YX48

Background:

Amylase used in the market is mostly medium-temperature enzyme or high-temperature enzyme and has poor enzyme activity under low-temperature environment. Acid α-amylase can be used to develop digestion additives in the pharmaceutical and healthcare industries. The amino acid sequence and structural differences among α-amylases obtained from various organisms are high enough to confer interesting biochemical diversity to the enzymes. However, low- temperature (0-50°C) amylase, with an optimum temperature and heat sensitivity, has a greater potential value than medium (50-80°C) and high (80-110°C) temperature amylases.

Methodology:

The gene amy48 from encoding extracellular α-amylase in Bacillus subtilis YX48 was successfully cloned into the pET30a (+) vector and expressed in Escherichia coli BL21 (DE3) for biochemical characterization.

Results and Conclusion:

The molecular weight of α-amylase was 75 kDa. The activity of α-amylase was not affected by Ca2+, and Amy48 had the best activity at pH 5.0 and 37°C. AMY48 has high stability over a narrow pH and temperature range (5.0-8.0 and 30-45°C). Amylase activity was strongly inhibited by Zn2+, Mn2+, Cu2+, and Fe2+ ions, but Na+, K+, and Co2+ ions stimulate its activity slightly. The purified enzyme showed gradually reduced activity in the presence of detergents. However, it was remarkably stable against EDTA and urea.

Overview of fermentation process: structure-function relationship on protein quality and non-nutritive compounds of plant-based proteins and carbohydrates

Demands for high nutritional value-added food products and plant-based proteins have increased over the last decade, in line with the growth of the human population and consumer health awareness. The quality of the plant-based proteins depends on their digestibility, amino acid content, and residues of non-nutritive compounds, such as phenolic compounds, anti-nutritional compounds, antioxidants, and saponins. The presence of these non-nutritive compounds could have detrimental effects on the quality of the proteins. One of the solutions to address these shortcomings of plant-based proteins is fermentation, whereby enzymes that present naturally in microorganisms used during fermentation are responsible for the cleavage of the bonds between proteins and non-nutritive compounds. This mechanism has pronounced effects on the non-nutritive compounds, resulting in the enhancement of protein digestibility and functional properties of plant-based proteins. We assert that the types of plant-based proteins and microorganisms used during fermentation must be carefully addressed to truly enhance the quality, functional properties, and health functionalities of plant-based proteins.Supplemental data for this article is available online at here. show.