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In this study, the intracellular β-galactosidases of Bacillus subtilis 4NK and Bacillus paralicheniformis 5NK isolated from Bingöl Binkap hot spring was partially purified and characterized. As a result of purification, the yield of the enzyme for B. subtilis 4NK was 85.2% and the purification fold was 2.8. The yield for B. paralicheniformis 5NK was 76.8% and the purification fold was 2.0. The optimum temperature of the enzyme was determined as 45 oC for B. subtilis 4NK and 55 oC for B. paralicheniformis 5NK and the optimum pH was 6.0 for both. In addition, in the thermal stability experiments even at the end of 120 min both enzymes were stable at 50 oC. It was determined that the partially purified enzyme activity increased in the presence of iodoacetamide and phenylmethylsulfonylfluoride for B. subtilis 4NK, dithiothreitol, N-ethylenemaleimide and phenylmethylsulfonylfluoride for B. paralicheniformis 5NK. The metals were found to activate the enzyme at low concentrations of Co2+, Cd2+ and Mn2+ for B. subtilis 4NK, Cu2+ and Cd2+ were found to inhibit the enzyme at high rates for B. paralicheniformis 5NK. Km and Vmax values for 4NK and 5NK, respectively; 23.80 mM, 1.978 μmol/min and 5.61 mM, 1.869 μmol/min.

The fossil fuel or petroleum derived plastics are applied in our routine life because of their easy availability. Distribution and contamination of the plastics in the landfills are the major reasons for these biodegradation study. This current study reveals the biodegradation of polypropylene films and the growth of Bacillus paralicheniformis and Lysinibacillus fusiformis isolated from plastic contaminated soil collected from municipality solid waste management site. The degradation rate of PP films was confirmed by the results of biodegradation analysis. The growth of Bacillus paralicheniformis and Lysinibacillus fusiformis had shown OD values at 600nm after the degradation period of 4 weeks increasing from 0.131 to 0.334 and 0.148 to 0.213 respectively. The viable cell count increased from 8×104cells/ml to 12×104cells/ml and 10.1×104 cells/ml to 15.2×104 cells/ml respectively. The physical and chemical changes of PP films were confirmed by FT-IR and XRD analysis. These analysis confirmed that the bacterial strains have the ability to change the chemical and physical nature of PP films and can utilize the PP films as sole carbon source.

As a prerequisite for probiotics to establish and settle in the host intestine, adhesion is an essential criterion for probiotic screening. However, adhesion of probiotics in the intestines of one of the most important cultured fish species globally, the grass carp Ctenopharyngodon idellus, remains understudied. Here, we assessed the adhesion properties of a novel potentially probiotic bacterial strain isolated from the grass carp intestine: Bacillus paralicheniformis FA6 (henceforth FA6). To indirectly determine the adhesion, we compared the hydrophobicity of FA6 with eight other bacterial strains, and found that FA6 had comparatively high hydrophobicity. To assess adhesion directly, we supplemented the feed with FA6 for 2 weeks, and then used immunofluorescence to study the dynamics of FA6 for 220 days after discontinuing the supplementation. The FA6 fluorescence signal plateaued between days 40 and 60, and remained visible in the grass carp guts until day 80. In addition, FA6 was re-isolated on day 220 from intestinal contents. Our results suggest that FA6 has high adhesion ability, and can colonize the grass carp intestine for long periods of time. This research provides a promising foundation for the application of FA6 in aquaculture.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Thermophilic bacteria, especially from the genus Bacillus, constitute a huge potential source of novel enzymes that could be relevant for biotechnological applications. In this work, we described the cellulose and hemicellulose-related enzymatic activities of the hot spring Bacillus aerius CCMM B940 from the Moroccan Coordinated Collections of Microorganisms (CCMM), and revealed its potential for hemicellulosic biomass utilization. Indeed, B940 was able to degrade complex polysaccharides such as xylan and lichenan and exhibited activity towards carboxymethylcellulose. The strain was also able to grow on agriculture waste such as orange and apple peels as the sole carbon source. Whole-genome sequencing allowed the reclassification of CCMM B940 previously known as B. aerius into Bacillus paralicheniformis since the former species name has been rejected. The draft genome reported here is composed of 38 contigs resulting in a genome of 4,315,004 bp and an average G + C content of 45.87%, and is an important resource for illuminating the molecular mechanisms of carbohydrate metabolism. The annotated genomic sequences evidenced more than 52 genes encoding glycoside hydrolases and pectate lyases belonging to 27 different families of CAZymes that are involved in the degradation of plant cell wall carbohydrates. Genomic predictions in addition to in vitro experiments have revealed broad hydrolytic capabilities of the strain, thus reinforcing its relevance for biotechnology applications.

Keratinase, a protease was produced from keratinolytic bacterium, Bacillus paralicheniformis MKU3, using poultry feather as substrate. Statistical analyses were carried out to enhance the activity of keratinase produced as a result of which enzyme activity was improved 6-fold yielding a maximum of 1872.5 U/ml and a specific activity of 1143.19 U/mg in 72 h. The keratinase produced was used to hydrolyze poultry feather waste which resulted in an almost 90% degradation by measurement of dry weight. Large scale production of keratinase was performed from 5-L to 500-L and it has been observed that an increase in the volume of bioreactor greatly improved the rate of production of keratinase along with a sharp decrease in production time. The keratinase produced was used to study dehairing on sheepskin and the efficiency was observed to be 100%. SEM and histochemical analysis on the skin confirmed efficient dehairing. The processed leather crust was further tested for physical strength and histochemistry wherein it has been proved that the quality of the leather crust produced is good. The environmental impact of the effluent produced as a result of dehairing was also assessed.

The inorganic selenium is absorbed and utilized inefficiently, and the range between toxicity and demand is narrow, so the application is strictly limited. Selenium nanoparticles have higher bioactivity and biosafety properties, including increased antioxidant and anticancer properties. Thus, producing and applying eco-friendly, non-toxic selenium nanoparticles in feed additives is crucial. Bacillus paralicheniformis Y4 was investigated for its potential ability to produce selenium nanoparticles and the activity of carboxymethyl cellulases. The selenium nanoparticles were characterized using zeta potential analyses, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). Additionally, evaluations of the anti-α-glucosidase activity and the antioxidant activity of the selenium nanoparticles and the ethyl acetate extracts of Y4 were conducted. B. paralicheniformis Y4 exhibited high selenite tolerance of 400 mM and the selenium nanoparticles had an average particle size of 80 nm with a zeta potential value of −35.8 mV at a pH of 7.0, suggesting that the particles are relatively stable against aggregation. After 72 h of incubation with 5 mM selenite, B. paralicheniformis Y4 was able to reduce it by 76.4%, yielding red spherical bio-derived selenium nanoparticles and increasing the carboxymethyl cellulase activity by 1.49 times to 8.96 U/mL. For the first time, this study reports that the carboxymethyl cellulase activity of Bacillus paralicheniforis was greatly enhanced by selenite. The results also indicated that B. paralicheniformis Y4 could be capable of ecologically removing selenite from contaminated sites and has great potential for producing selenium nanoparticles as feed additives to enhance the added value of agricultural products.

To meet the present and forecasted market demand, bacterial alkaline phosphatase (ALP) production must be increased through innovative and efficient production strategies. Using sugarcane molasses and biogenic apatite as low-cost and easily available raw materials, this work demonstrates the scalability of ALP production from a newfound Bacillus paralicheniformis strain APSO isolated from a black liquor sample. Mathematical experimental designs including sequential Plackett–Burman followed by rotatable central composite designs were employed to select and optimize the concentrations of the statistically significant media components, which were determined to be molasses, (NH4)2NO3, and KCl. Batch cultivation in a 7-L stirred-tank bioreactor under uncontrolled pH conditions using the optimized medium resulted in a significant increase in both the volumetric and specific productivities of ALP; the alkaline phosphatase throughput 6650.9 U L−1, and µ = 0.0943 h−1; respectively, were obtained after 8 h that, ameliorated more than 20.96, 70.12 and 94 folds compared to basal media, PBD, and RCCD; respectively. However, neither the increased cell growth nor enhanced productivity of ALP was present under the pH-controlled batch cultivation. Overall, this work presents novel strategies for the statistical optimization and scaling up of bacterial ALP production using biogenic apatite.

Deep-subsurface aquifers, buried thousands of meters down the Earth’s crust, belong to the most underexplored microbial habitats. Although a few studies revealed the existence of microbial life at the depths, the knowledge about the microbial life in the deep hydrosphere is still scarce due to the limited access to such environments. Studying the subsurface microbiome provides unique information on microbial diversity, community structure, and geomicrobiological processes occurring under extreme conditions of the deep subsurface. Our study shows that low-diversity microbial assemblages in subsurface hot brines were dominated by the bacteria involved in biogeochemical cycles of sulfur and nitrogen. Based on genomic and physiological analyses, we found that the Bacillus paralicheniformis isolate obtained from the brine under study differed from the mesophilic species in the presence of specific adaptations to harsh environmental conditions. We indicate that some lineages of B. paralicheniformis are halothermophilic, which was not previously reported., Deep-subsurface hot brines in northwest Poland, extracted through boreholes reaching 1.6 and 2.6 km below the ground surface, were microbiologically investigated using culture-independent and culture-dependent methods. The high-throughput sequencing of 16S rRNA gene amplicons showed a very low diversity of bacterial communities, which were dominated by phyla Proteobacteria and Firmicutes. Bacterial genera potentially involved in sulfur oxidation and nitrate reduction (Halothiobacillus and Methylobacterium) prevailed in both waters over the sulfate reducers (“Candidatus Desulforudis” and Desulfotomaculum). Only one archaeal taxon, affiliated with the order Thermoplasmatales, was detected in analyzed samples. Bacterial isolates obtained from these deep hot brines were closely related to Bacillus paralicheniformis based on the 16S rRNA sequence similarity. However, genomic and physiological analyses made for one of the isolates, Bacillus paralicheniformis strain TS6, revealed the existence of more diverse metabolic pathways than those of its moderate-temperature counterpart. These specific traits may be associated with the ecological adaptations to the extreme habitat, which suggest that some lineages of B. paralicheniformis are halothermophilic. IMPORTANCE Deep-subsurface aquifers, buried thousands of meters down the Earth’s crust, belong to the most underexplored microbial habitats. Although a few studies revealed the existence of microbial life at the depths, the knowledge about the microbial life in the deep hydrosphere is still scarce due to the limited access to such environments. Studying the subsurface microbiome provides unique information on microbial diversity, community structure, and geomicrobiological processes occurring under extreme conditions of the deep subsurface. Our study shows that low-diversity microbial assemblages in subsurface hot brines were dominated by the bacteria involved in biogeochemical cycles of sulfur and nitrogen. Based on genomic and physiological analyses, we found that the Bacillus paralicheniformis isolate obtained from the brine under study differed from the mesophilic species in the presence of specific adaptations to harsh environmental conditions. We indicate that some lineages of B. paralicheniformis are halothermophilic, which was not previously reported.

The objective of this work was to evaluate the effectiveness of the putative biocontrol agents (PBA) Bacillus paralicheniformis and Trichoderma asperelloides in vitro and in vivo to control two of the most important tomato plant diseases: vascular wilt (Fusarium oxysporum) and early blight (Alternaria alternata). The assessment of the in vitro interactions between the PBA and the phytopathogenic fungi was performed by dual confrontation assays. The biocontrol effectiveness of the individual and combined PBA treatments towards individual phytopathogen inoculations was evaluated in tomato plants. T. asperelloides was able to exert an outstanding mycoparasitic effect on both phytopathogenic fungi in the in vitro tests by hyphal strangulation and penetration. In addition, the individual PBA treatments were effective in the biocontrol of A. alternata and F. oxysporum in tomato plants reducing the plant disease severity in more than 53.8 and 66.7% for each of the pathogens, respectively. On the other hand, the combined use of the tested strains showed similar effectiveness in the biocontrol of A. alternata, but no synergism was observed. In addition, it was concluded that B. paralicheniformis protected the plants from the attack of A. alternata through the induction of the systemic resistance of the plant. This study demonstrated the effectiveness of the individual and combined use of the strains tested for the biocontrol of A. alternata and F. oxysporum in tomato plants.

To avoid the use of agrochemicals in agriculture, alternative methods are emerging to control plant pathogens. Some plant growth-promoting rhizobacteria (PGPR) can be used as biocontrol agents since they can induce protection against pathogens. The aim of this study was to evaluate the protective effect of several PGPR strains against the main Fusarium species involved in asparagus decline syndrome (ADS): F. proliferatum, F. oxysporum f. sp. asparagi and F. redolens. In vitro antagonism assays showed that all the bacteria inhibited the mycelium growth of the three Fusarium species. The most effective strains (Streptomyces fradiae Hvs6, Bacillus paralicheniformis Hvs2 and Bacillus velezensis FC37) were tested to evaluate their protective effect on asparagus plants inoculated with pathogenic Fusarium isolates. Strains FC37 and Hvs2 were the most effective in controlling pathogenic F. proliferatum and F. oxysporum f. sp. asparagi, but neither could protect against F. redolens isolates. The production of hydrolytic enzymes such as β-glucosidase, amylase and protease by these bacterial strains could be involved in the structural degradation of the fungal cell wall. In addition, the production of toxic volatile compounds, such as hydrogen cyanide, may inhibit the fungal growth, and the production of phosphate solubilizers could be related to the plant growth promotion. These results suggest that strains FC37 and Hvs2 could be used as potential biocontrol agents as a sustainable and environmentally friendly control strategy for ADS-affected fields.

We report the complete genome sequence and annotation of Bacillus paralicheniformis strain CBMAI 1303, a bacterium applied for phytopathogen biocontrol.

Bacillus paralicheniformis MDJK30 was isolated from the rhizosphere of a peony. It could control the pathogen of peony root rot. Here, we report the complete genome sequence of B. paralicheniformis MDJK30. Eleven secondary metabolism gene clusters were predicted.

To effectively protect against oxidative damage, an important trace element, selenium, which was initially described as a toxin and subsequently shown to be an essential antioxidant, came into researchers’ view. Meanwhile, probiotics, as nonpathogenic microorganisms that can resist host small intestinal digestion and reach the colon alive, were reported to exert a myriad of beneficial effects, including balance of intestinal microbiota, improvement of growth, enhancement of immune response and inhibition of some pathogenic bacteria. Thus, selenium-enriched probiotics, which have the advantages of both two of them, have been developed to enhance the body’s antioxidant capability and immune function and protect against various oxidative stresses. However, the potential mechanisms of selenium-enriched probiotics’ functions remain unclear. Therefore, we produced a novel kind of selenium-enriched probiotic called S-BPSR via Bacillus Paralicheniformis SR14. We investigated the antioxidant effects of S-BPSR against oxidative stress and its underlying molecular mechanisms in IPEC-J2 cells. Concretely, we found that S-BPSR had the great abilities on scavenging DPPH, superoxide anion, hydroxyl radical, and could increase cell viability and prevented lactate dehydrogenase release into the medium when prior to H2O2 exposure. H2O2-induced reactive oxygen species and malondialdehyde were remarkably suppressed by S-BPSR, which also effectively attenuated cell apoptosis. Treatment with S-BPSR also separately increased the levels of antioxidant enzymes and promoted the expression of phosphorylation of ERK and p38 MAPK signaling pathways in IPEC-J2 cells. These results suggested that this new form of selenium-enriched probiotic possessed great antioxidant property and cytoprotection and may indeed have broad applications in oxidative stress-related diseases.