Response of sweet potato cultivars to Bacillus velezensis T149-19 and Bacillus safensis T052-76 used as biofertilizers

The global market of sweet potato (Ipomoea batatas (L.) Lam.) is continuously growing and, consequently, demands greater productivity from the agricultural sector. The use of biofertilizers facilitates plant growth by making essential nutrients available to crops or providing resistance against different abiotic and biotic factors. The strains Bacillus safensis T052-76 and Bacillus velezensis T149-19 have previously been inoculated in the sweet potato cultivar Ourinho, showing positive effects on plant shoot growth and inhibiting the phytopathogen Plenodomus destruens. To elucidate the effects of these strains on sweet potato growth, four different cultivars of sweet potato were selected: Capivara, IAPAR 69, Rosinha de Verdan and Roxa. The plants were grown in pots in a greenhouse and inoculated with the combined strains according to a randomized block design. A control (without the inoculation of both strains) was also used. A slight positive effect of the inoculation of the two Bacillus strains was observed on the aerial parts of some of the cultivars. An increase in the fresh weight of the sweet potatoes of the inoculated plants was obtained, varying from 2.7 to 11.4 %. The number of sweet potatoes obtained from the inoculated cultivars IAPAR 69 and Roxa increased 15.2 % and 16.7 %, respectively. The rhizosphere soil of each cultivar was further sampled for DNA extraction, and the 16S rRNA gene metabarcoding technique was used to determine how the introduction of these Bacillus strains influenced the rhizosphere bacterial community. The bacterial communities of the four different cultivars were dominated by Actinobacteria, Proteobacteria and Firmicutes. Nonmetric multidimensional scaling (NMDS) revealed that the rhizosphere bacterial communities of plants inoculated with Bacillus strains were more similar to each other than to the bacterial communities of uninoculated plants. This study highlights the contribution of these Bacillus strains to the promotion of sweet potato growth.

Harnessing the potential of microbial keratinases for bioconversion of keratin waste

The increasing global consumption of poultry meat has led to the generation of a vast quantity of feather keratin waste daily, posing significant environmental challenges due to improper disposal methods. A growing focus is on utilizing keratinous polymeric waste, amounting to millions of tons annually. Keratins are biochemically rigid, fibrous, recalcitrant, physiologically insoluble, and resistant to most common proteolytic enzymes. Microbial biodegradation of feather keratin provides a viable solution for augmenting feather waste's nutritional value while mitigating environmental contamination. This approach offers an alternative to traditional physical and chemical treatments. This review focuses on the recent findings and work trends in the field of keratin degradation by microorganisms (bacteria, actinomycetes, and fungi) via keratinolytic and proteolytic enzymes, as well as the limitations and challenges encountered due to the low thermal stability of keratinase, and degradation in the complex environmental conditions. Therefore, recent biotechnological interventions such as designing novel keratinase with high keratinolytic activity, thermostability, and binding affinity have been elaborated here. Enhancing protein structural rigidity through critical engineering approaches, such as rational design, has shown promise in improving the thermal stability of proteins. Concurrently, metagenomic annotation offers insights into the genetic foundations of keratin breakdown, primarily predicting metabolic potential and identifying probable keratinases. This may extend the understanding of microbial keratinolytic mechanisms in a complex community, recognizing the significance of synergistic interactions, which could be further utilized in optimizing industrial keratin degradation processes.

Draft genome sequence data on Bacillus safensis U41 isolated from soils of Santiniketan, India

The draft genome sequence of an isolate of Bacillus safensis U41 from the soils of Santiniketan (23040'12″ N and 87039'52″ E) is reported here. Bacillus safensis is a bacterium that produces cellulases, which is essential for the breakdown of plant biomass. As such, it is a valuable source of digestive enzymes from plant biomass, especially cellulases. The genomic DNA was extracted from a single colony using a QIAgen Blood and Tissue kit (QIAgen Inc., Canada). Sequencing was performed via Illumina HiSeq X using 2 × 150 paired-end chemistry, generating 7,352,576 reads with sequence coverage of 509x. The assembly produced 20 contigs over 200 base pairs (bp) in length, with an N50 value of 901304 and an L50 of 2. The genome size was 3,732,407 bp, and the average GC content was 41.43 %. Genome annotation and gene predictions were performed using Prokka v.1.14.6, which identified 3783 coding sequences, 64 tRNA genes, and 3 rRNA genes.

Development of functional consortia for the pretreatment of compostable lignocellulosic waste: A simple and effective solution to a large-scale problem

Microorganisms drive the degradation of organic matter thanks to their enzymatic versatility. However, the structure of lignocellulose poses a great challenge for the microbiota inhabiting a compost pile. Our purpose was to increase the biodegradability of vegetable waste in the early stages of the composting process by applying a microbial consortium with lignocelllulolytic capacity. For this, a previous screening was performed among the culturable microbiota from different composting processes to find inoculants with ligninocellulolytic activity. Selected strains were applied as a pure culture and as a microbial consortium. The starting material was composed of tomato plant and pruning remains mixed in a ratio (50:50 v/v), whose humidity was adjusted to around 65%. To determine the ability of both treatments to activate the biodegradation of the mixtures, moisture, organic matter, ash, C/N ratio, 4-day cumulative respirometric index (AT4) and degradation rates of cellulose, hemicellulose and lignin were evaluated. Subsequently, a real composting process was developed in which the performance of the microbial consortium was compared with the composting process without inoculum (control). According to our tests, three microbial strains (Bacillus safensis, Bacillus licheniformis and Fusarium oxysporum) were selected. The results showed that the application of the bacteria strains at low doses (104 CFU g-1 on the complete residual material of the pile) resulted in higher rates of lignocelullose degradation after 10 days of treatment compared to that observed after application of the fungus in pure culture or untreated controls. The implementation of the strategy described in this work resulted in obtaining compost with better agronomic quality than the uninoculated controls. Therefore, the application of this consortium could be considered as an interesting tool for bioactivation of lignocellulosic waste prior to the composting process.

Endophytic Bacillus vallismortis and Bacillus tequilensis bacteria isolated from medicinal plants enhance phosphorus acquisition and fortify Brassica napus L. vegetative growth and metabolic content

Phosphorus fertilization imposes critical limitations on crop productivity and soil health. The aim of the present work is to explore the potential of two phosphate solubilizing bacteria (PSB) species in phosphorus supplementation of canola (Brassica napus L.). Out of 38 bacterial isolates obtained from nine medicinal plants, two bacterial strains (20P and 28P) were proved as the most potent for the in-vitro tricalcium phosphate solubilization test. These isolates verified their activity toward different enzymes as nitrogenase and alkaline phosphatase. Also, 20P and 28P gave a high amount of indole-3-acetic acid, 34.16 μg/ml and 35.20 μg/ml, respectively, and were positive for siderophores production as they detected moderate affinity for iron chelation. Molecular identification confirmed that strain 20P was Bacillus vallismortis and strain 28P was Bacillus tequilensis. A pot experiment was conducted to study the effect of four different phosphorus concentrations (0%, 50%, 75%, and 100% P) each alone and/or in combination with B. vallismortis, B. tequilensis, or both bacterial isolates on the vegetative growth and some physiological parameters of canola. The combined treatment of 50% phosphorus + (B. vallismortis + B. tequilensis) was generally the most effective with respect to shoot height, shoot dry mass, leaf area, photosynthetic pigment fractions, total sugar content, and accumulated NPK content. In contrast, the rhizosphere pH reached the minimum value under the same treatment. These findings highlighted the potential use of PSB (B. vallismortis and B. tequilensis) along with phosphorus fertilization as a safe sustainable tactic.

A scientific version of understanding "Why did the chickens cross the road"? - A guided journey through Bacillus spp. towards sustainable agriculture, circular economy and biofortification

The world, a famished planet with an overgrowing population, requires enormous food crops. This scenario compelled the farmers to use a high quantity of synthetic fertilizers for high food crop productivity. However, prolonged usage of chemical fertilizers results in severe adverse effects on soil and water quality. On the other hand, the growing population significantly consumes large quantities of poultry meats. Eventually, this produces a mammoth amount of poultry waste, chicken feathers. Owing to the protein value of the chicken feathers, these wastes are converted into protein hydrolysate and further extend their application as biostimulants for sustained agriculture. The protein profile of chicken feather protein hydrolysate (CFPH) produced through Bacillus spp. was the maximum compared to physical and chemical protein extraction methods. Several studies proved that the application of CFPH and active Bacillus spp. culture to soil and plants results in enhanced plant growth, phytochemical constituents, crop yield, soil nutrients, fertility, microbiome and resistance against diverse abiotic and biotic stresses. Overall, "CFPH - Jack of all trades" and "Bacillus spp. - an active camouflage to the surroundings where they applied showed profound and significant benefits to the plant growth under the most adverse conditions. In addition, Bacillus spp. coheres the biofortification process in plants through the breakdown of metals into metal ions that eventually increase the nutrient value of the food crops. However, detailed information on them is missing. This can be overcome by further real-world studies on rhizoengineering through a multi-omics approach and their interaction with plants. This review has explored the best possible and efficient strategy for managing chicken feather wastes into protein-rich CFPH through Bacillus spp. bioconversion and utilizing the CFPH and Bacillus spp. as biostimulants, biofertilizers, biopesticides and biofortificants. This paper is an excellent report on organic waste management, circular economy and sustainable agriculture research frontier.

Microbial and Qualitative Traits of Quinoa and Amaranth Seeds from Experimental Fields in Southern Italy

Quinoa and amaranth are of special interest since they are increasingly used for the development of new bakery products with enhanced nutritional value. The aim of the study was to evaluate the agronomic, microbiological, and nutritional characteristics of quinoa and amaranth seeds grown in Southern Italy. For this reason, quinoa Titicaca and three amaranth accessions (5, 12, and 14) were cultivated in different experimental fields in the Campania Region and analyzed for the cultivation aspects, chemical composition, and microbiological quality of the seeds. All seeds showed a good adaptability to cultivation in the experimental areas of the Mediterranean basin. Quinoa seeds were characterized by their higher protein, fat, and ash content than the amaranth seeds, which were characterized by their higher value in dietary fiber. All seeds, regardless of the geographical area of production, were contaminated with yeasts, moulds, and spore-forming bacteria, mainly Bacillus cereus, B. licheniformis, B. safensis and B. subtilis, as identified by 16S rRNA sequencing analysis. So, the detection of Bacillus spp. must be strongly monitored, as quinoa and amaranth seeds could be used in bread production, where they can cause ropiness, resulting in great economic losses for the industries.

Mustard seed–associated endophytes suppress Sclerotinia sclerotiorum causing Sclerotinia rot in mustard crop

Mustard-rapeseed cultivation is affected by Sclerotinia sclerotiorum resulting in loss of oil yield and degradation of crop quality. This study adopted an environment friendly biocontrol approach of screening mustard endophytes against the pathogen. Two bacterial isolates, Bacillus safensis (TS46 bac4) and Bacillus australimaris (SM2) showed potential biocontrol activity under both in vitro and in vivo conditions. Dual culture assay reported 90% inhibition of fungal growth. The bacterial cell free supernatant of isolate SM2 showed 52.89% inhibition and the other isolate TS46 bac4 showed 57.97% inhibition. The crude (10 mg/ml) and purified (10 mg/ml) metabolite extract of SM2 showed 100% and 97% inhibition respectively. Both crude (10 mg/ml) and purified (7.5 mg/ml) metabolite extract of TS46 bac4 exhibited 99% inhibition of the pathogen. Antifungal lipopeptides: surfactin, iturin and fengycin were identified in bacterial metabolite extract of the isolates. Both strains promoted healthy germination and prevented the formation of any disease symptoms in seedling. The selected Bacillus strains applied by spray method showed better results against fungal infection on mustard leaf and stem. Microscopic studies revealed degradation of fungal mycelial growth by both isolates. These findings support the employment of the bacterial strains as potential biocontrol agents to reduce the effects of S. sclerotiorum in mustard-rapeseed.

Genomic analysis of two Bacillus safensis isolated from Merzouga desert reveals desert adaptive and potential plant growth-promoting traits

Deserts represent extreme environments for microorganisms, and conditions such as high soil salinity, nutrient deficiency, and increased levels of UV radiation make desert soil communities of high biotechnological potential. In this study, we isolated, sequenced, and assembled the genomes of Bacillus safensis strains BcP62 and Bcs93, to which we performed comparative genome analyses. Using the DDH and ANI of both strains with the available B. safensis genomes, we identified three potential subspecies within this group. Intra-species core genome phylogenetic analysis did not result in clustering genomes by niche type, with some exceptions. This study also revealed that the genomes of the analyzed strains possessed plant growth-promoting characteristics, most of which were conserved in all B. safensis strains. Furthermore, we highlight the genetic features of B. safensis BcP62 and Bcs93 related to survival in the Merzouga desert in Morocco. These strains could be potentially used in agriculture as PGPB in extreme environments, given their high tolerability to unfavorable conditions.

Larvicidal, antioxidant and biotoxicity assessment of (2-(((2-ethyl-2 methylhexyl)oxy)carbonyl)benzoic acid isolated from Bacillus pumilus against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus

Mosquitoes are a vector for many dreadful diseases known for their public health concern. The continued use of synthetic insecticides against vector control has led to serious environmental impacts, human health problems, and the development of insect resistance. Hence, alternative mosquito control methods are needed to protect the environment and human health. In the present study, the bioefficacy of (2-(((2-ethyl-2 methylhexyl)oxy)carbonyl) benzoic acid isolated from Bacillus pumilus were tested against Aedes aegypti, Culex quinquefasciatus and Anopheles stephensi. The isolated bioactive compound was characterized through thin layer chromatography (TLC), UV-visible spectroscopy (UV), Fourier-transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, and gas chromatography-mass spectrometry analysis. The pure compound caused a high percent mortality rate in a dose-dependent manner, the obtained values were 96, 82, 69, 50 and 34%; 86, 72, 56, 43, and 44%; 100, 90, 83, 70 and 56% against Ae. aegypti, Cx. quinquefasciatus, and An. stephensi respectively. The effective lethal concentration values (LC₅₀) were 13.65, 14.90 and 9.64 ppm against Ae. aegypti, Cx. quinquefasciatus, An. Stephensi, respectively. The effect of (2-(((2-ethyl-2 methylhexyl)oxy)carbonyl) benzoic acid significantly increased the superoxide dismutase, catalase, α, β esterase and Glutathione-S-transferase level after 24 h of the treatment period. The comet assay confirmed that isolated compound causes DNA damage in all tested insects. Histopathological examinations of treated larvae showed shrunken body posture, damaged epithelial cells and microvillus as compared to control organisms. The biosafety of the isolated compound was assessed against G. affinis and did not produce mortality which confirmed that the activity of the isolated compound is species specific. The current study concludes that the critical success factors of new insecticidal agent development are based on the eco-compatibility and alternative tools for the pesticide producing industry.

Gut Bacterial Flora of Open Nested Honeybee, Apis florea

Honeybees are eusocial insects with close interaction with their surrounding environment. Gut microbiota in honeybees play a significant role in host health, biology, and interaction behavior with the surrounding environment. Apis florea, a wild bee, is the most primitive among all honeybees and is indigenous to the Indian subcontinent. Previous reports on reared honeybee species provide information on the gut microbiome. No such studies are reported on the gut microbiota of the wild honeybee species. This study aimed at studying the gut microbiome of the wild honeybee species, A. florea. The study reports the analysis and the identification of gut bacteria in the wild honeybee species, A. florea, employing culture-based and culture-independent methods. Cultured bacteria were identified and characterized by MALDI-TOF MS and 16S rRNA sequencing. A comprehensive analysis and identification of non-culturable bacteria were performed by 16S rRNA amplicon next-generation sequencing. This approach splits gut bacteria into four bacterial phyla, four families, and 10 genera in major. The dominant taxa identified in A. florea belonged to the family Enterobacteriaceae (79.47%), Lactobacillaceae (12.75%), Oxalobacteraceae (7.45%), and Nocardiaceae (0.13%). The prevailing bacteria belonged to Enterobacter, Lactobacillus, Escherichia-Shigella, Massilia, Klebsiella, Citrobacter, Pantoea, Serratia, Rhodococcus, and Morganella genera, belonging to phyla Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes. This study observed the occurrence of a few bacteria that are not previously reported for their occurrence in other species of the Apis genus, making this investigation highly relevant with regard to the bee microbiome.

Biosafe Management of Botrytis Grey Mold of Strawberry Fruit by Novel Bioagents

Recently, there have been urgent economic and scientific demands to decrease the use of chemical fungicides during the treatment of phytopathogens, due to their human health and environmental impacts. This study explored the biocontrol efficacy of novel and eco-friendly preen (uropygial) oil and endophytic Bacillus safensis in managing postharvest Botrytis grey mold in strawberry fruit. The preen oil (25 μL/mL) showed high antifungal activity against B. cinerea Str5 in terms of the reduction in the fungal radial growth (41.3%) and the fungal colony-forming units (28.6%) compared to the control. A new strain of Bacillus safensis B3 had a good potential to produce chitinase enzymes (3.69 ± 0.31 U/mL), hydrolytic lipase (10.65 ± 0.51 U/mL), and protease enzymes (13.28 ± 0.65 U/mL), which are responsible for the hydrolysis of the B. cinerea Str5 cell wall and, consequently, restrict fungal growth. The in vivo experiment on strawberry fruit showed that preen (uropygial) oil reduced the disease severity by 87.25%, while the endophytic bacteria B. safensis B3 reduced it by 86.52%. This study reports the efficiency of individually applied bioagents in the control of phytopathogenic fungi for the first time and, consequently, encourages their application as a new and innovative strategy for prospective agricultural technology and food safety.

Indian oil sardine (Sardinella longiceps) gut derived Bacillus safensis SDG14 with enhanced probiotic competence for food and feed applications

Probiotics are considered as functional food as they provide health benefits along with traditional nutrition. Spore forming probiotic Bacillus are of commercial interest than Lactic Acid Bacillus due to their relatively lower cost of production and higher survivability. In the present study we identified the bacterial strain SDG14 isolated from Indian oil Sardine by Average Nucleotide Identity of whole genome sequence. The whole genome of SDG14 was also explored for pathogenicity, the presence of genes responsible for probiotic traits such as spore formation, resistance to host gastrointestinal tract conditions, adhesion to intestinal mucosa, interference in pathogen survival, expression of bacteriocins, oxidative and other stress responses, absorption of nutrition, production of essential amino acids and vitamins. Wet lab experiments for probiotic characterization were also conducted. The organism was confirmed to be Bacillus safensis SDG14. The possible pathogenicity of the organism was also ruled out by in silico analysis. Bacillus safensis SDG14 was able to survive at pH 3 and bile salt concentration of 0.5% (w/v). The adhesion index of Bacillus safensis SDG14 on HEp-2 was 36.82 ± 5.93 and 45.54 ± 9.55 respectively after 60 and 90 min of incubation and self aggregation percentage was 18.4 ± 0.48% after 3 h. Bacillus safensis SDG14 produced bacteriocin and co-aggregated with E. coli, Salmonella Typhimurium and Pseudomonas aeruginosa. The genomic data supported the findings of wet lab study and vice versa. Bacillus safensis SDG14 was proved to be a non-pathogenic, spore forming, pH and bile salt resistant, bacteriocin, amino acid and vitamin producing probiotic with proposed food and feed applications.

Probiotic Bacillus safensis NPUST1 Administration Improves Growth Performance, Gut Microbiota, and Innate Immunity against Streptococcus iniae in Nile tilapia (Oreochromis niloticus)

Probiotics are considered ecofriendly alternatives to antibiotics as immunostimulants against pathogen infections in aquaculture. In the present study, protease-, amylase-, cellulase-, and xylanase-producing Bacillus safensis NPUST1 were isolated from the gut of Nile tilapia, and the beneficial effects of B. safensis NPUST1 on growth, innate immunity, disease resistance and gut microbiota in Nile tilapia were evaluated by feeding tilapia a basal diet or basal diet containing 105 and 106-107 CFU/g for 8 weeks. The results showed that the weight gain, feed efficiency and specific growth rate were significantly increased in tilapia fed a diet containing 106 CFU/g and 107 CFU/g B. safensis NPUST1. Intestinal digestive enzymes, including protease, amylase and lipase, and hepatic mRNA expression of glucose metabolism and growth-related genes, such as GK, G6Pase, GHR and IGF-1, were also significantly increased in the 106 CFU/g and 107 CFU/g B. safensis NPUST1 treated groups. Immune parameters such as phagocytic activity, respiratory burst and superoxide dismutase activity in head kidney leukocytes, serum lysozyme, and the mRNA expression of IL-1β, IL-8, TNF-α and lysozyme genes were significantly induced in the head kidney and spleen of 106 CFU/g and 107 CFU/g B. safensis NPUST1 treated fish. The cumulative survival rate was significantly increased in fish fed a diet containing 106 CFU/g and 107 CFU/g B. safensis NPUST1 after challenge with Streptococcus iniae. Dietary supplementation with B. safensis NPUST1 improves the gut microbiota of Nile tilapia, which increases the abundance of potential probiotics and reduces the abundance of pathogenic pathogens. The present study is the first to report the use of B. safensis as a potential probiotic in aquaculture, and a diet containing 106 CFU/g B. safensis NPUST1 is adequate for providing beneficial effects on growth performance and health status in tilapia.

Novel metabolites from Bacillus safensis and their antifungal property against Alternaria alternata

Plant growth promoting rhizobacteria offer an effective and eco-sustainable solution to protect crops against phytopathogens. In the present study, Bacillus safensis STJP (NAIMCC-B-02323) from the rhizospheric soil of Stevia rebaudiana showed strong biocontrol activity against phytopathogen, Alternaria alternata. B. safensis STJP produced antifungal volatile organic compounds (AVOC). In the presence of AVOC, there was no conidia germination, mycelium growth was inhibited, and hyphae ruptured as observed by scanning electron microscopy. When mycelium of the fungus from bacterial treated plate was transferred into fresh potato dextrose agar plate, A. alternata could not grow. Extracted AVOC from B. safensis STJP were identified by thin-layer chromatography (TLC), Fourier-transform-infrared (FTIR) spectroscopy and gas-chromatography-mass spectrometry (GC-MS). In total 25 bacterial metabolites were identified by GC-MS analysis having alcohol, alkane, phenol, alkyl halide and aromatic compounds. Five of these (phenol, 2,4-bis (1,1-dimethylethyl)-, 3-hexadecanol, pyrrolo(1,2-a)pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl)-, 5,10-diethoxy-2,3,7,8-tetrahydro-1H,6H-dipyrrolo(1,2-a:1',2'-d)pyrazine and hexadecanoic acid) inhibited the mycelium growth, controlling spore formation and conidia germination of A. alternata. This study concluded that AVOC producing B. safensis can be used as a green-fungicide against A. alternata. Bacterial metabolites could pave the way for the development of next generation biopesticides. This can be a reliable technology to enhance the quality and reliability of biopesticides.

Isolation, identification and reviewing the health effect of HPC bacteria in household point-of-use (PoU) water treatment devices: a case study, Ahvaz, Iran

In Ahwaz, a city in west southern Iran, the majority of households are using Point of Use (PoU) water treatment units. The heterotrophic plate count (HPC) bacteria were isolated from these units while they were mounted on water distribution system in order to determine the variations in HPC and diversity of the bacterial population using polymerase chain reaction (PCR). Results showed that bacterial population regrowth in PoU units could increase HPC exceeding the limit of the 500 CFU/mL in outlet water. In around 70% of the input water samples, the HPC was less than 500 CFU/ml with a mean of 226.7 (CI 95%: 28.1-425.3). HPC in output treated water samples had an increasing trend from the start of the unit operation with a mean of 2416.4 (CI 95%: 1074.9-3757.9). Out of 49 detected bacterial strains, 20 strains were Gram-negative and 29 Gram-positive. Bacillus was the most frequent genes detected in inlet and outlet water samples. Most of the identified bacterial strains were opportunistic pathogens potentially dangerous for immunocompromised population. HPC population in PoU units significantly can be increased during a one-month period of operation, so replacement of the filters must be done regularly.

A magainin-2 like bacteriocin BpSl14 with anticancer action from fish gut Bacillus safensis SDG14

Bacteriocins are gaining utmost importance in antimicrobial and chemotherapy due to their diverse structure and activity. This study centres on magainin-2 like bacteriocin with anticancer action, produced by Bacillus safensis strain SDG14 isolated from gut of marine fish Sardinella longiceps. The purified bacteriocin designated as BpSl14 was thermostable and pH tolerant. The molecular weight of BpS114 was estimated to be 6061.2 Da using MALDI-ToF MS. The partial primary sequence was elucidated by peptide mass fingerprinting using MALDI MS/MS. The tertiary structure of the partial sequence was similar to that of two magainin-2 α-helices joined together by extended indolicidin. The BpSl14 protein inhibited the cells of lung carcinoma, one of the deadliest cancers. Docking studies conducted with DR5 and TGF-β, two of the most prominent apoptotic receptors in adenocarcinoma, also proved the anti-apoptotic action of BpSl14.

Complete Genome Sequence of Bacillus safensis Strain 3A, a Heavy Metal-Resistant Bacterium Isolated from Contaminated Estuarine Sediment in Brazil

Bacillus safensis 3A was isolated from a contaminated estuarine sediment sample with mine tailing from the Samarco dam disaster, which occurred in 2015 in Minas Gerais State, Brazil. We report here a draft genome sequence (3.6 Mb) of this bacterial strain. B. safensis exhibited strong resistance to heavy metals.

Antifungal potential against Sclerotinia sclerotiorum (Lib.) de Bary and plant growth promoting abilities of Bacillus isolates from canola (Brassica napus L.) roots

Endophytic bacteria show important abilities in promoting plant growth and suppressing phytopathogens, being largely explored in agriculture as biofertilizers or biocontrol agents. Bacteria from canola roots were isolated and screened for different plant growth promotion (PGP) traits and biocontrol of Sclerotinia sclerotiorum. Thirty isolates belonging to Bacillus, Paenibacillus, Lysinibacillus, and Microbacterium genera were obtained. Several isolates produced auxin, siderophores, hydrolytic enzymes, fixed nitrogen and solubilized phosphate. Five isolates presented antifungal activity against S. sclerotiorum by the dual culture assay and four of them also inhibited fungal growth by volatile organic compounds production. All antagonistic isolates belonged to the Bacillus genus, and had their genomes sequenced for the search of biosynthetic gene clusters (BGC) related to antimicrobial metabolites. These isolates were identified as Bacillus safensis (3), Bacillus pumilus (1), and Bacillus megaterium (1), using the genomic metrics ANI and dDDH. Most strains showed several common BGCs, including bacteriocin, polyketide synthase (PKS), and non-ribosomal peptide synthetase (NRPS), related to pumilacidin, bacillibactin, bacilysin, and other antimicrobial compounds. Pumilacidin-related mass peaks were detected in acid precipitation extracts through MALDI-TOF analysis. The genomic features demonstrated the potential of these isolates in the suppression of plant pathogens; however, some aspects of plant-bacterial interactions remain to be elucidated.

In Vitro Preformed Biofilms of Bacillus safensis Inhibit the Adhesion and Subsequent Development of Listeria monocytogenes on Stainless-Steel Surfaces

Listeria monocytogenes continues to be one of the most important public health challenges for the meat sector. Many attempts have been made to establish the most efficient cleaning and disinfection protocols, but there is still the need for the sector to develop plans with different lines of action. In this regard, an interesting strategy could be based on the control of this type of foodborne pathogen through the resident microbiota naturally established on the surfaces. A potential inhibitor, Bacillus safensis, was found in a previous study that screened the interaction between the resident microbiota and L. monocytogenes in an Iberian pig processing plant. The aim of the present study was to evaluate the effect of preformed biofilms of Bacillus safensis on the adhesion and implantation of 22 strains of L. monocytogenes. Mature preformed B. safensis biofilms can inhibit adhesion and the biofilm formation of multiple L. monocytogenes strains, eliminating the pathogen by a currently unidentified mechanism. Due to the non-enterotoxigenic properties of B. safensis, its presence on certain meat industry surfaces should be favored and it could represent a new way to fight against the persistence of L. monocytogenes in accordance with other bacterial inhibitors and hygiene operations.

Novel keratinolytic enzymes, discovered from a talented and efficient bacterial keratin degrader

Huge quantities of keratinaceous waste are a substantial and almost totally unexploited protein resource which could be upgraded for use as high value-added products by efficient keratinolytic enzymes. In this study, we found that Bacillus sp. 8A6 can efficiently degrade chicken feather after 24 h growth. According to phylogenetic analysis, the strain (formerly identified as Bacillus pumilus 8A6) belongs to the B. pumilus species clade but it is more closely related to B. safensis. Hotpep predicted 233 putative proteases from Bacillus sp. 8A6 genome. Proteomic analysis of culture broths from Bacillus sp. 8A6 cultured on chicken feathers or on a mixture of bristles and hooves showed high abundance of proteins with functions related to peptidase activity. Five proteases (one from family M12, one from family S01A, two from family S08A and one from family T3) and four oligopeptide and dipeptide binding proteins were highly expressed when Bacillus sp. 8A6 was grown in keratin media compared to LB medium. This study is the first to report that bacterial proteases in families M12, S01A and T3 are involved in keratin degradation together with proteases from family S08.

Whole-Genome Sequences of an Abortive Bacillus safensis Strain Isolated from a Mare's Uterus

This is a report of two Bacillus safensis genomes sequenced from separate cultures isolated from the uterus of a 16-year-old Westphalian mare that aborted a dead fetus. This strain represents the first case of a B. safensis-associated equine abortion and the first case of infection caused by this bacterium.

Compost Tea Reduces the Susceptibility of Pinus radiata to Fusarium circinatum in Nursery Production

Nutrition is one of the factors that most limits forestry plant growth; thus, current production in nurseries is based on conventional fertilization focused on enhancing vigor. However, an excessive intake of mineral nitrogen can cause morphological imbalances and the formation of more succulent tissues which, consequently, increase susceptibility to plant pathogens. Fusarium circinatum is the causal agent of pitch canker in plants of the Pinus genus, with Pinus radiata being the species most susceptible to this disease. This study compares the response of P. radiata seedlings to infection by F. circinatum as influenced by two fertilizers-conventional and aerated compost tea (ACT)-applied during the nursery phase. The potential of ACT against F. circinatum was first tested in vitro, where it was found to inhibit the pathogen's mycelial growth and conidial germination. In the greenhouse, infected plants fertilized with ACT exhibited less severe internal and external symptoms of pitch canker and lower levels of pathogen colonization of both stems and needles than with conventional fertilizer. An analysis of the hormone content and defense-related gene expression shows greater salicylic acid production and phenylalanine ammonium-lyase and chalcone synthase expression in ACT-fertilized pine. All of the parameters assessed are consistent in showing that biofertilization with ACT reduces the susceptibility of pine seedlings to the disease compared with conventional fertilization.

Screening of bacterial strains from the gut of Pacific White Shrimp (Litopenaeus vannamei) and their efficiencies in improving the fermentation of soybean meal

Microbial fermentation is an efficient, economical and eco-friendly approach to overcome the limitations in soybean meal replacement of fish meal in aquaculture. However, little research focused on the development of shrimp-derived strains for fermentation of SBM. In this study, Bacillus sanfensis (SQVG18) and Bacillus stratosphericus (SQVG22) were screened from shrimp intestine for fermentation according to the activities of protease, cellulase and phytase. The optimized fermentation conditions of SQVG18 and SQVG22 were as follow: fermentation temperature (40°C vs 35°C), fermentation time (48h both), inoculation amount [4% both (v/m)], solid-liquid ratio [1:1.2 vs 1:1 (g/ml)]. After 48 h fermentation, SQVG18 and SQVG22 increased crude protein content by 6.93% and 5.95%, respectively; degraded most of macromolecular proteins to micromolecular proteins (< 20 kDa); improved amino acids profiles, like lysine and methionine in particular; significantly decreased the anti-nutritional factors such as trypsin inhibitor, glycinin and β-conglycinin (P < 0.05). In addition, both strains were observed no hemolytic activity, less antibiotic resistance genes and definite inhibition to common shrimp pathogens of Vibrio alginolyticus sp. and Vibrio parahaemolyticus sp. These results indicated that both strains could improve nutrition values of soybean meal effectively and have potential applications in shrimp culture.

Development of Bacillus safensis-based liquid bioformulation to augment growth, stevioside content, and nutrient uptake in Stevia rebaudiana

The application of chemical fertilizers to enhance crop production is a major concern due to associated environmental pollution and health hazards. Hence, there is an urgent need to develop an eco-friendly solution to improve crop production and promote sustainable agriculture simultaneously. Stevia rebaudiana is an important medicinal crop being substitute for sugar, superior flavor outline, extensive medicinal properties, and also of agronomic interest. In the present study, bacterium STJP isolated from the rhizospheric soil of S. rebaudiana and identified as Bacillus safensis on the basis of 16S rRNA gene sequencing, showed good amount of zinc (4.4 mg/L) and potassium (5.4 mg/L) solubilization. Paneer-whey (a dairy waste) based bioformulation (P-WBF) was developed utilizing isolate B. safensis STJP (accession number NAIMCC TB-2833) and inspected for the quality and ability to enhance the growth, nutrients uptake, and stevioside content in S. rebaudiana. The application of P-WBF displayed a significantly higher concentration (153.12%) of stevioside in S. rebaudiana as compared to control. P-WBF treated Stevia plants showed significantly higher fresh and dry weight as well (as compared to control). Further, enhancement of phosphorous, nitrogen, potassium, and zinc uptake in plant tissue was also recorded by application of P-WBF. This study suggests the use of P-WBF based biofertilizer using B. safensis STJP to increase stevioside content in Stevia plant by a nutrient(s) linked mechanism. This novel approach can also be beneficial for utilization of a dairy waste in preparation of bioformulation and, for enhancement of crop yield by an ecofriendly manner leading to sustainable agriculture.

Draft Genome Sequence of Bacillus safensis Strain Sami, Isolated from Leaf Veins of Ficus religiosa

Here, I report the draft genome sequence of a novel Bacillus safensis strain, Sami, isolated from leaf veins of Ficus religiosa F. religiosa is a large tree native to the Indian subcontinent and Indochina. The draft genome of B. safensis is 3.67 Mb.

Biotechnological Potential of Bacteria Isolated from the Sea Cucumber Holothuria leucospilota and Stichopus vastus from Lampung, Indonesia

In order to minimize re-discovery of already known anti-infective compounds, we focused our screening approach on understudied, almost untapped marine environments including marine invertebrates and their associated bacteria. Therefore, two sea cucumber species, Holothuria leucospilota and Stichopus vastus, were collected from Lampung (Indonesia), and 127 bacterial strains were identified by partial 16S rRNA-gene sequencing analysis and compared with the NCBI database. In addition, the overall bacterial diversity from tissue samples of the sea cucumbers H. leucospilota and S. vastus was analyzed using the cultivation-independent Illumina MiSEQ analysis. Selected bacterial isolates were grown to high densities and the extracted biomass was tested against a selection of bacteria and fungi as well as the hepatitis C virus (HCV). Identification of putative bioactive bacterial-derived compounds were performed by analyzing the accurate mass of the precursor/parent ions (MS1) as well as product/daughter ions (MS2) using high resolution mass spectrometry (HRMS) analysis of all active fractions. With this attempt we were able to identify 23 putatively known and two previously unidentified precursor ions. Moreover, through 16S rRNA-gene sequencing we were able to identify putatively novel bacterial species from the phyla Actinobacteria, Proteobacteria and also Firmicutes. Our findings suggest that sea cucumbers like H. leucospilota and S. vastus are promising sources for the isolation of novel bacterial species that produce compounds with potentially high biotechnological potential.

Fungal xylanases-mediated synthesis of silver nanoparticles for catalytic and biomedical applications

Green synthesis of nanoparticles has fuelled the use of biomaterials to synthesise a variety of metallic nanoparticles. The current study investigates the use of xylanases of Aspergillus niger L3 (NEA) and Trichoderma longibrachiatum L2 (TEA) to synthesise silver nanoparticles (AgNPs). Characterisation of AgNPs was carried out using UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy, while their effectiveness as antimicrobial, antioxidant, catalytic, anticoagulant, and thrombolytic agents were determined. The colloidal AgNPs was brownish with surface plasmon resonance at 402.5 and 410 nm for NEA-AgNPs and TEA-AgNPs, respectively; while FTIR indicated that protein molecules were responsible for the capping and stabilisation of the nanoparticles. The spherical nanoparticles had size of 15.21-77.49 nm. The nanoparticles significantly inhibited the growth of tested bacteria (63.20-88.10%) and fungi (82.20-86.10%), and also scavenged DPPH (37.48-79.42%) and hydrogen peroxide (20.50-96.50%). In addition, the AgNPs degraded malachite green (78.97%) and methylene blue (25.30%). Furthermore, the AgNPs displayed excellent anticoagulant and thrombolytic activities using human blood. This study has demonstrated the potential of xylanases to synthesise AgNPs which is to the best of our knowledge the first record of such. The present study underscores the relevance of xylanases in nanobiotechnology.

Phosphate-solubilizing Bacillus sp. enhances growth, phosphorus uptake and oil yield of Mentha arvensis L

In the present study, phosphate solubilizing rhizobacterial isolate STJP from the rhizosphere of Stevia rebaudiana was identified as a Bacillus sp. on the basis of phenotypic, biochemical, and 16S rRNA gene sequencing. In addition to phosphate solubilization ability, isolate Bacillus sp. STJP produced a significant quantity of siderophore (16.06 µg/ml) and indole 3-acetic acid (30.59 µg/ml). In the greenhouse experiment, treatment with STJP along with tricalcium phosphate (TCP200) showed significant increase in the plant growth parameters, oil yield and P uptake in M. arvensis as compared to the control plants. Amongst all the treatments, highest oil yield and menthol content were observed when treated with Bacillus sp. STJP + TCP200. Hence, an integrated approach of using Bacillus sp. STJP along with TCP can be used to increase the production of menthol and oil yield of M. arvensis. This approach of using fertilizer along with phosphate solubilizing Bacillus sp. worked very well and was more effective in comparison with individual treatment of fertilizer or plant growth promoting rhizobacteria. A combined use of efficient phosphate solubilising bacteria loaded with plant growth promoting characters along with TCP can thus be far effective way for enhancing the yield of crops in a sustainable manner.

Draft Genome Sequence of Bacillus safensis Strain JG-B5T, Isolated from a Uranium Mining Waste Pile

Bacillus safensis strain JG-B5T was isolated from soil of the uranium mining waste pile Haberland located near Johanngeorgenstadt, Saxony, Germany. We report here a draft genome sequence (3.7 Mb) of this bacterial strain. The high metal resistance abilities of B. safensis strain JG-B5T can be exploited for bioremediation of metal and metalloid-contaminated environments.

Bacillus safensis with plant-derived smoke stimulates rice growth under saline conditions

Salinity is a worldwide environmental problem of agricultural lands. Smoke and plant growth-promoting bacteria (PGPR) are individually used to improve plant growth, but the combined effects of these have not been studied yet under saline conditions. The combined effect of plant growth-promoting bacteria Bacillus safensis and plant-derived smoke Cymbopogon jwarancusa was studied under different salinity level as 50, 100, and 150 mM on rice (cv. Basmati-385). Smoke dilutions of C. jwarancusa (C-500 and C-1000) and bacterial culture of B. safensis were used to soak seeds for 10 h. It was observed that the salt concentration decreases the germination percentage, vegetative growth, ion contents (K⁺ and Ca²⁺), and photosynthetic pigments (Chl "a," Chl "b," and carotene) while an increase occurred in Na⁺, total soluble protein (TSP), proline, total soluble sugar, catalase (CAT), and peroxidase (POD) contents. The combined effect of B. safensis and smoke primed seeds increased the germination percentage, seedling growth, ion contents (K⁺, Ca²⁺), and photosynthetic pigments (Chl "a," Chl "b," carotene) and reduced the Na⁺ ion content, total soluble protein, proline content, total soluble sugar, CAT, and POD activity by lowering the drastic effect of salt stress. It was concluded that combined effect of smoke and PGPR is more effective than individual effect.

Biotechnological Applications of Marine Enzymes From Algae, Bacteria, Fungi, and Sponges

Diversity is the hallmark of all life forms that inhabit the soil, air, water, and land. All these habitats pose their unique inherent challenges so as to breed the "fittest" creatures. Similarly, the biodiversity from the marine ecosystem has evolved unique properties due to challenging environment. These challenges include permafrost regions to hydrothermal vents, oceanic trenches to abyssal plains, fluctuating saline conditions, pH, temperature, light, atmospheric pressure, and the availability of nutrients. Oceans occupy 75% of the earth's surface and harbor most ancient and diverse forms of organisms (algae, bacteria, fungi, sponges, etc.), serving as an excellent source of natural bioactive molecules, novel therapeutic compounds, and enzymes. In this chapter, we introduce enzyme technology, its current state of the art, unique enzyme properties, and the biocatalytic potential of marine algal, bacterial, fungal, and sponge enzymes that have indeed boosted the Marine Biotechnology Industry. Researchers began exploring marine enzymes, and today they are preferred over the chemical catalysts for biotechnological applications and functions, encompassing various sectors, namely, domestic, industrial, commercial, and healthcare. Next, we summarize the plausible pros and cons: the challenges encountered in the process of discovery of the potent compounds and bioactive metabolites such as biocatalysts/enzymes of biomedical, therapeutic, biotechnological, and industrial significance. The field of Marine Enzyme Technology has recently assumed importance, and if it receives further boost, it could successfully substitute other chemical sources of enzymes useful for industrial and commercial purposes and may prove as a beneficial and ecofriendly option. With appropriate directions and encouragement, marine enzyme technology can sustain the rising demand for enzyme production while maintaining the ecological balance, provided any undesired exploitation of the marine ecosystem is avoided.

Biomedical and Catalytic Applications of Gold and Silver-Gold Alloy Nanoparticles Biosynthesized Using Cell-Free Extract of Bacillus Safensis LAU 13: Antifungal, Dye Degradation, Anti-Coagulant and Thrombolytic Activities

This study investigated the green biosynthesis of gold (Au) and silver-gold alloy (Ag-Au) nanoparticles using cell-free extract of Bacillus safensis LAU 13 strain (GenBank accession No: KJ461434). The biosynthesized AuNPs and Ag-AuNPs were characterized using UV-Vis spectroscopy, Fourier-transform infrared spectroscopy, and transmission electron microscopy. Evaluation of the antifungal activities, degradation of malachite green, anti-coagulation of blood, and thrombolysis of human blood clot by the biosynthesized nanoparticles were investigated. The AuNPs and Ag-AuNPs had maximum absorbance at 561 and 545 nm, respectively. The FTIR peaks at 3318, 2378, 2114, 1998, 1636, 1287, 446, 421 cm^-1 for AuNPs; and 3310, 2345, 2203, 2033, 1636, 1273, 502, 453, 424 cm^-1 for Ag-AuNPs indicated that proteins were the capping and stabilization molecules in the biosynthesized nanoparticles. The particles were fairly spherical in shape with size of 10-45 nm for AuNPs and 13-80 nm for Ag-AuNPs. Moreover, energy dispersive X-ray analysis of AuNPs revealed gold as the most prominent metal in the AuNPs solution, while silver and gold were the most prominent in the case of Ag-AuNPs. Selected area electron diffraction showed the biosynthesized nanoparticles as crystal structures with ring shape pattern. AuNPs and Ag-AuNPs displayed growth inhibitions of 66.67-90.78% against strains of Aspergillus fumigatus and A. niger at concentration of 200 μg/ml , and remarkable degradation (> 90%) of malachite green after 48 h. Furthermore, the nanoparticles prevented coagulation of blood, and also completely dissolved blood clots, indicating the biomedical potential of AuNPs and Ag-AuNPs in the management of blood coagulation disorders. This is the first report of the synthesis of AuNPs and Ag-AuNPs using a strain of B. safensis for biomedical and catalytic applications.