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In this study, we used a multifaceted approach to select robust bioaugmentation candidates for enhancing biogas production and to demonstrate the usefulness of a genome-centric approach for strain selection for specific bioaugmentation purposes. We also investigated the influence of the isolation source of bacterial strains on their metabolic potential and their efficiency in enhancing anaerobic digestion. Whole genome sequencing, metabolic pathway reconstruction, and physiological analyses, including phenomics, of phylogenetically diverse strains, Rummeliibacillus sp. POC4, Ochrobactrum sp. POC9 (both isolated from sewage sludge) and Brevundimonas sp. LPMIX5 (isolated from an agricultural biogas plant) showed their diverse enzymatic activities, metabolic versatility and ability to survive under varied growth conditions. All tested strains display proteolytic, lipolytic, cellulolytic, amylolytic, and xylanolytic activities and are able to utilize a wide array of single carbon and energy sources, as well as more complex industrial by-products, such as dairy waste and molasses. The specific enzymatic activity expressed by the three strains studied was related to the type of substrate present in the original isolation source. Bioaugmentation with sewage sludge isolates–POC4 and POC9–was more effective for enhancing biogas production from sewage sludge (22% and 28%, respectively) than an approach based on LPMIX5 strain (biogas production boosted by 7%) that had been isolated from an agricultural biogas plant, where other type of substrate is used. [ABSTRACT FROM AUTHOR]

Bordetella bronchiseptica, an emerging zoonotic pathogen, infects a broad range of mammalian hosts. B. bronchiseptica-associated atrophic rhinitis incurs substantial losses to the pig breeding industry. The true burden of human disease caused by B. bronchiseptica is unknown, but it has been postulated that some hypervirulent B. bronchiseptica isolates may be responsible for undiagnosed respiratory infections in humans. B. bronchiseptica was shown to acquire antibiotic resistance genes from other bacterial genera, especially Escherichia coli. Here, we present a new B. bronchiseptica lytic bacteriophage—vB_BbrP_BB8—of the Podoviridae family, which offers a safe alternative to antibiotic treatment of B. bronchiseptica infections. We explored the phage at the level of genome, physiology, morphology, and infection kinetics. Its therapeutic potential was investigated in biofilms and in an in vivoGalleria mellonella model, both of which mimic the natural environment of infection. The BB8 is a unique phage with a genome structure resembling that of T7-like phages. Its latent period is 75 ± 5 min and its burst size is 88 ± 10 phages. The BB8 infection causes complete lysis of B. bronchiseptica cultures irrespective of the MOI used. The phage efficiently removes bacterial biofilm and prevents the lethality induced by B. bronchiseptica in G. mellonella honeycomb moth larvae. [ABSTRACT FROM AUTHOR]

Recycling of waste electrical and electronic equipment including spent batteries focuses on maximizing the material recovery efficiency (of metals, polymers, or solvents) and decreasing the negative environmental impact of leachates that remain after the treatment (i.e. the secondary wastes). The major aim of this study was to develop a novel, low-cost biochemical treatment technology for the management of effluents generated during sulfuric acid–based hydrometallurgical recycling of spent alkaline batteries. We explored the use of various chemical reagents (40% NaOH, 20% Na 2 CO 3 , and 1% NH 3(aq)) and biogenic ammonia produced by urea-degrading bacteria to increase the pH of the effluents (from pH 0.5 to pH 5.0) and prepare them for further treatment by sulfate-reducing bacteria. Comparisons of the pretreatment efficiency and metal and sulfate removal yields, as well as the characterization of the neutralization products (sediments and effluents) showed that the most promising results were obtained when the raw leachates were treated with 40% NaOH (to reach pH 3.5), followed by the addition of biogenic ammonia (to reach pH 5.0). Sulfate-reducing bacteria (SRB) activity led to a further pH increase (up to ~7.3), almost complete (99%) sulfate removal and metal sulfide (ZnS, MnS) precipitation, as up to ~99% of Zn and Mn were removed in SRB cultures to which appropriately diluted pretreated leachates had been added. The presented study indicated that the pretreatment and neutralization of hydrometallurgical effluents based on the use of urea-degrading and sulfate-reducing bacteria could be an attractive alternative to conventional chemical treatment. • Gradual acidic leachate pretreatment with sodium hydroxide and biogenic ammonia. • Biogenic ammonia synthesized by urea-degrading bacteria. • Combined biological and chemical pretreatment promotes the growth and activity of SRB. • Sulfates and metals were almost completely removed and metal sulfides precipitated. [ABSTRACT FROM AUTHOR]