The Alternating Growth of Bacteria within a Consortium During Desulfurization of Coal

Efforts to reduce organic sulfur in coal are taken through biodesulfurization by using desulfurization bacteria to release covalently-bound sulfur from the coal matrix. Coal is a complex hydrocarbon material that requires collaboration from more than one type of bacteria in a consortium for desulfurization. The current study shows how the individual members of a bacterial consortium obtained directly from coal samples grew on the coal. Mineral medium containing sub-bituminous coal with a concentration of 10%, 15%, and 20% served as a carbon source and the only sulfur to support the consortium's growth. The examination included growth patterns, concentrations of dibenzothiophene as an organic sulfur representative, pH, and sulfate concentration as the sulfur product released into the medium. The growth of individual members of the consortium was observed for 336 h. The consortium grew in all three coal concentrations with slightly different cell growth patterns and the release of dibenzothiophene. Members of the consortium grew alternately and overlapped, which showed possible linkages or dependence on products and existence from the growth of other members. The existence of the primary strain Moraxella osloensis COK1 indicated that they played a role in the activities and growth of other members. The alternating growth is discussed to produce a hypothetical illustration of how several other members play in using sulfur in a well-known desulfurization pathway. In conclusion, this study provides a deeper insight into the value of consortium members individually but growing together while swarming coal as a complex resource to become low-sulfur coal.

Antimicrobial Resistance Profiling and Phylogenetic Analysis of Neisseria gonorrhoeae Clinical Isolates From Kenya in a Resource-Limited Setting

BackgroundAfrica has one of the highest incidences of gonorrhea. Neisseria gonorrhoeae is gaining resistance to most of the available antibiotics, compromising treatment across the world. Whole-genome sequencing (WGS) is an efficient way of predicting AMR determinants and their spread in the population. Recent advances in next-generation sequencing technologies like Oxford Nanopore Technology (ONT) have helped in the generation of longer reads of DNA in a shorter duration with lower cost. Increasing accuracy of base-calling algorithms, high throughput, error-correction strategies, and ease of using the mobile sequencer MinION in remote areas lead to its adoption for routine microbial genome sequencing. To investigate whether MinION-only sequencing is sufficient for WGS and downstream analysis in resource-limited settings, we sequenced the genomes of 14 suspected N. gonorrhoeae isolates from Nairobi, Kenya.MethodsUsing WGS, the isolates were confirmed to be cases of N. gonorrhoeae (n = 9), and there were three co-occurrences of N. gonorrhoeae with Moraxella osloensis and N. meningitidis (n = 2). N. meningitidis has been implicated in sexually transmitted infections in recent years. The near-complete N. gonorrhoeae genomes (n = 10) were analyzed further for mutations/factors causing AMR using an in-house database of mutations curated from the literature.ResultsWe observe that ciprofloxacin resistance is associated with multiple mutations in both gyrA and parC. Mutations conferring tetracycline (rpsJ) and sulfonamide (folP) resistance and plasmids encoding beta-lactamase were seen in all the strains, and tet(M)-containing plasmids were identified in nine strains. Phylogenetic analysis clustered the 10 isolates into clades containing previously sequenced genomes from Kenya and countries across the world. Based on homology modeling of AMR targets, we see that the mutations in GyrA and ParC disrupt the hydrogen bonding with quinolone drugs and mutations in FolP may affect interaction with the antibiotic.ConclusionHere, we demonstrate the utility of mobile DNA sequencing technology in producing a consensus genome for sequence typing and detection of genetic determinants of AMR. The workflow followed in the study, including AMR mutation dataset creation and the genome identification, assembly, and analysis, can be used for any clinical isolate. Further studies are required to determine the utility of real-time sequencing in outbreak investigations, diagnosis, and management of infections, especially in resource-limited settings.

Enhanced Nitrogen Removal of Wastewater at Low Temperature by Iterative Screening of Cold-Tolerant Denitrifying Bacteria

The biological denitrification for wastewater treatment in winter is often seriously compromised due to the effects of low-temperature (<13 °C) on metabolic activity of microorganism. In this study, an excellent cold-tolerant denitrifying bacterium, Moraxella osloensis LT-01 was isolated by iterative domestication. The strain LT-01 retained about 60% maximal growth activity at 10 °C. Under initial concentrations of 100 mg/L, average ammonium, nitrate and nitrite removal efficiencies for domestic wastewater (C/N 4:1) at 10 °C were 70.35%, 65.39% and 61.74% in 24 h, respectively. Nitrogen balance analysis showed that about 46% of TN was directed toward in the dissimilation form of gas, and 16% of TN was assimilated for cell growth. Key genes hydroxylamine reductase gene (HAO) and nitrite reductase (NirS) involved in nitrification and denitrification processes were identified by gene-specific PCR, indicating that strain LT-01 perform nitrogen removal efficiently via unique simultaneous nitrification and denitrification. These results suggest the bacterium LT-01 has great potential as an effective performer for treating domestic wastewater in winter.

Moraxella osloensis as a part of genital tract microbiota in infertility: incidental findings or pathology markers?

Aim. To assess the potential role of M. osloensis in genital microbiota of infertile males and females..Materials and methods. Samples from men’s urethra and women’s posterior vaginal fornix in barren couples of the reproductive age were examined. Cultivation was carried out using elective culture media with subsequent identification of strains by biochemical properties. A metagenomic study of 16S ribosomal RNA samples was performed on the Illumina MiSeq platform using the MiSeq Reagent Kits v3 kit (600-Cycle Kit).Results. Metagenomic study of samples from genital tracts of barren married couples, as well as from patients with suspected «acute genital gonococcal infection» demonstrated that all samples (100%) contained fragments of the Moraxella spp. genome, mostly in a huge amount, among which M. osloensis occupied leading positions. In women, the proportion of M. osloensis was twice as large as in men (25.3 ± 9.0 and 11.7 ± 9.3%, respectively). A high frequency of association of M. osloensis with other opportunistic pathogens, G. vaginalis and E. faecalis in particular, was established. It appears that M. osloensis can contribute to development of asymptomatic inflammatory process. Moreover, the constant presence of moraxellas in the microbiota during gonococcal infection may indicate their certain pathogenetic activity, and the synergistic nature of the relationship between M. osloensis and N. gonorrhoeae.Conclusion. We assume that it is M. osloensis that forms the consortia determining pathosymbiocenosis in the reproductive organs. In this context, we propose to consider a decrease in fertility with a steadily established symbiocenosis, including moraxella, as an indicative condition for this pathology, and M. osloensis as its marker.

Characterization of the human skin resistome and identification of two microbiota cutotypes

Background The human skin microbiota is considered to be essential for skin homeostasis and barrier function. Comprehensive analyses of its function would substantially benefit from a catalog of reference genes derived from metagenomic sequencing. The existing catalog for the human skin microbiome is based on samples from limited individuals from a single cohort on reference genomes, which limits the coverage of global skin microbiome diversity. Results In the present study, we have used shotgun metagenomics to newly sequence 822 skin samples from Han Chinese, which were subsequently combined with 538 previously sequenced North American samples to construct an integrated Human Skin Microbial Gene Catalog (iHSMGC). The iHSMGC comprised 10,930,638 genes with the detection of 4,879,024 new genes. Characterization of the human skin resistome based on iHSMGC confirmed that skin commensals, such as Staphylococcus spp, are an important reservoir of antibiotic resistance genes (ARGs). Further analyses of skin microbial ARGs detected microbe-specific and skin site-specific ARG signatures. Of note, the abundance of ARGs was significantly higher in Chinese than Americans, while multidrug-resistant bacteria (“superbugs”) existed on the skin of both Americans and Chinese. A detailed analysis of microbial signatures identified Moraxella osloensis as a species specific for Chinese skin. Importantly, Moraxella osloensis proved to be a signature species for one of two robust patterns of microbial networks present on Chinese skin, with Cutibacterium acnes indicating the second one. Each of such “cutotypes” was associated with distinct patterns of data-driven marker genes, functional modules, and host skin properties. The two cutotypes markedly differed in functional modules related to their metabolic characteristics, indicating that host-dependent trophic chains might underlie their development. Conclusions The development of the iHSMGC will facilitate further studies on the human skin microbiome. In the present study, it was used to further characterize the human skin resistome. It also allowed to discover the existence of two cutotypes on the human skin. The latter finding will contribute to a better understanding of the interpersonal complexity of the skin microbiome.

Microbiological investigations of two thermal baths in Budapest, Hungary. Report: effect of bathing and pool operation type on water quality

In Hungary, which is famous for its thermal baths, according to the regulations, waters are investigated in hygienic aspects with standard cultivation methods. In the present study, two thermal baths were investigated (the well and three different pool waters in both) using cultivation methods, taxon-specific polymerase chain reactions (PCRs), multiplex PCRs and next-generation amplicon sequencing. Mainly members of the natural microbial community of the well waters and bacteria originating from the environment were detected but several opportunistic pathogenic taxa, e.g., Pseudomonas aeruginosa, P. stutzeri, Acinetobacter johnsoni, Acinetobacter baumanni, Moraxella osloensis, Microbacterium paraoxydans, Legionella spp., Stenotrophomonas maltophilia and Staphylococcus aureus were revealed by the applied methods. Pools with charging-unloading operation had higher microscopic cell counts, colony-forming unit (CFU) counts, number of cocci, P. aeruginosa and S. aureus compared to the recirculation systems. Bacteria originating from human sources (e.g., skin) were identified in the pool waters with less than 1% relative abundance, and their presence was sporadic in the pools. Comparing the microbiological quality of the pools based on the first sampling time and the following four months' period it was revealed that recirculation operation type has better water quality than the charging-unloading pool operation from a hygienic point of view.