Enhanced production and organic solvent stability of a protease from Brevibacillus laterosporus strain PAP04

Partitioning purification, biochemical characterization, and milk coagulation efficiency of protease from a newly Streptomyces sp. isolate

An actinobacteria strain was isolated from an olive waste mill and tested for protease production on skimmed milk media. The strain identification was achieved through both 16 S rDNA sequencing and phenotypic characterization. The enzyme was purified using the ammonium sulfate/t-butanol three-phase partitioning (TPP) method, followed by characterization to investigate the effect of pH, temperature, and various chemical agents. Subsequently, the enzyme was assessed for its milk coagulation activity. The strain belonging to the Streptomyces genera, exhibits significant phylogenetic and phenotypic differences from the aligned species, suggesting its novelty as a new strain. The enzyme was best separated in the TPP aqueous phase with a 5.35 fold and 56.25% yield. Optimal activity was observed at pH 9.0 and 60 °C, with more than half of the activity retained within the pH range of 7-10 over one hour. The protease demonstrated complete stability between 30 and 60 °C. While metallic ions enhanced enzyme activity, EDTA acted as an inhibitor. The enzyme displayed resistance to H2O2, SDS, Tween 80, and Triton X-100. Notably, it was activated in organic solvents (ethyl acetate, petroleum ether, and xylene), maintaining > 75% of its original activity in butanol, ethanol, and methanol. Additionally, the enzyme yielded high milk coagulant activity of 11,478 SU/mL. The new Streptomyces sp. protease revealed high activity and stability under a wide range of biochemical conditions. Its use in the dairy industry appears particularly promising. Further industrial process investigations will be valuable in determining potential uses for this enzyme.

Evaluation of probiotic properties of a Brevibacillus laterosporus strain

Brevibacillus laterosporus is a strain of probiotic bacteria that has been widely used in pest control, cash crop, and other production areas. However, few studies have been conducted on its use as a feed additive in animals. Therefore, the probiotic potential of B. laterosporus PBC01 was evaluated by characterizing hydrophobicity, auto-aggregation activity, bile salt and simulated gastrointestinal fluid tolerance, bienzymatic, and antibacterial activity. Antibiotic susceptibility, hemolysis assays, and supplemental feeding of mice were also performed to evaluate safety features. Our results showed that B. laterosporus PBC01 had moderate hydrophobicity, high auto-agglutination ability. Meanwhile, B. laterosporus PBC01 had good tolerance to bile salt and simulated gastrointestinal fluid. It had the ability to secrete protease, cellulase, and to inhibit various pathogens. In addition, B. laterosporus PBC01 was sensitive to many antibiotics, and did not produce hemolysin. In the safety assessment of mice, it did not cause any deaths, nor did it affect the cell components of blood, antioxidant capacity, and reproductive health. The study indicated the great probiotic characteristics and safety of B. laterosporus PBC01. This may provide a theoretical basis for the clinical application and development of probiotic-based feed additives.

Isolation, screening, and identification of chitinase-producing bacterial strains from riverbank soils at Ambo, Western Ethiopia

Chitinases are hydrolytic enzymes that dissolve the glycosidic linkages in chitin. Chitin is a cell wall component of fungi and fund in exoskeleten of worms and arthropods. Chitinase has been applied in agriculture, as a biopesticide for the control of plant fungal infections, in medicine, and in waste management. This research aimed to isolate, screen, and identification of chitinase-producing bacteria from riverbank soils. Twenty nine chitinolytic bacteria were isolated from the river bank soil samples, from which 9 of them had strong chitinolytic properties. Chitinase production was determined by zones of hydrolysis produced after 96 h of incubation at 37 °C. The different bacterial isolates were characterized morphologically, microscopically, and biochemically and finally eight strain were identified at species level by Matrix Assisted Laser Desorption Ionization - Time of Flight Mass Spectrometry (MALDI-TOF MS). From the eight, bacterial isolates investigated in this study Stenotrophomonas maltophilia showed the highest chitinase enzyme activity (625 μg/mL) followed by Pseudomonas putida with the enzyme activity of (553 μg/mL) and the least enzyme activity was recorded for Lilliottia amnigena (80 μg/mL). An incubation temperature of 45 °C, neutral pH and an incubation period of 96 h are found to be the optimum condition for the chitinase enzyme production from Stenotrophomonas maltophilia. The results of this study indicated the possibility of the production of chitinase from the chitinolytic bacterial isolates, which was highly useful for a variety of applications, including biocontrol of harmful insects and pathogenic fungi as well as in the biochemical, pharmaceutical, and medical sectors.

Production of proline and protease with different organic wastes in bacteria (Production proline and protease with organic wastes)

In this study, we investigated the proline and protease production of different bacteria in several organic waste materials. Our aim was to produce proline and protease economically in waste that is abundantly available while reducing its environmental impact. 5 ml of different organic waste materials (OWW: Olive waste water; N.B: Nutrient Broth; EW: Eggshell; PBS: PBS buffer; PLW: Peach leaf wastes; TCW: Turkish coffee wastes; TWW: Tea waste water; WCW: Waste cheese whey; WFO: Waste frying oil) were placed in 10 ml grow tubes, inoculated and incubated for 24 h. Phosphate-buffered saline and 10% solutions of different organic wastes were added. These cultures were subsequently incubated at 37°C for 24 h. Cells were harvested at 24 h for L-proline assay. 1 ml of culture was transferred by pipette into an Eppendorf tube and centrifuged at 14,000 rpm for 20 min at room temperature. Cellular debris was removed by centrifuge and the supernatant was used for proline activity assays. Protease activity was determined using a modified method with casein as the substrate. We found that proline and protease can easily be produced economically using Turkish coffee wastes (TCW), Waste cheese whey (WCW) and Olive waste water (OWW) organic waste. We believe that this study will result in similar research leading to the economical use of these waste materials thus reducing their impact on the environment.

Identification of a Novel Thermostable Alkaline Protease from Bacillus megaterium-TK1 for the Detergent and Leather Industry

Simple Summary

In the current investigation, we describe the characteristic features of a novel Bacillus megaterium bacterium-derived protease with excellent thermostable enzyme activity under stringent alkaline conditions. The protease is highly compatible with various detergents and thus appears to be an eco-friendly additive for a variety of industrial applications.

Abstract

An increased need by the green industry for enzymes that can be exploited for eco-friendly industrial applications led us to isolate and identify a unique protease obtained from a proteolytic Bacillus megaterium-TK1 strain from a seawater source. The extracellular thermostable serine protease was processed by multiple chromatography steps. The isolated protease displayed a relative molecular weight (MW) of 33 kDa (confirmed by zymography), optimal enzyme performance at pH 8.0, and maximum enzyme performance at 70 °C with 100% substrate specificity towards casein. The proteolytic action was blocked by phenylmethylsulfonyl fluoride (PMSF), a serine hydrolase inactivator. Protease performance was augmented by several bivalent metal cations. The protease tolerance was studied under stringent conditions with different industrial dispersants and found to be stable with Surf Excel, Tide, or Rin detergents. Moreover, this protease could clean blood-stained fabrics and showed dehairing activity for cow skin with significantly reduced pollution loads. Our results suggest that this serine protease is a promising additive for various eco-friendly usages in both the detergent and leather industries.

A Novel Protein Elicitor PeBL2, from Brevibacillus laterosporus A60, Induces Systemic Resistance against Botrytis cinerea in Tobacco Plant

Here, we reported a novel secreted protein elicitor PeBL2 from Brevibacillus laterosporus A60, which can induce hypersensitive response in tobacco (Nicotiana benthamiana). The ion-exchange chromatography, high-performance liquid chromatography (HPLC) and mass spectrometry were performed for identification of protein elicitor. The 471 bp PeBL2 gene produces a 17.22 kDa protein with 156 amino acids containing an 84-residue signal peptide. Consistent with endogenous protein, the recombinant protein expressed in Escherichia coli induced the typical hypersensitive response (HR) and necrosis in tobacco leaves. Additionally, PeBL2 also triggered early defensive response of generation of reactive oxygen species (H₂O₂ and O₂ ^-) and systemic resistance against of B. cinerea. Our findings shed new light on a novel strategy for biocontrol using B. laterosporus A60.