Metagenomic insights into the variation of bacterial communities and potential pathogenic bacteria in drinking water treatment and distribution systems

High-throughput sequencing of 16S rRNA gene amplicons was conducted to characterize the changing patterns of bacterial community and potential pathogens in full-scale drinking water treatment and distribution systems.Results showed that Actinobacteria was the predominant phylum in source water,while Proteobacteria dominated after chlorine disinfection and its relative abundance increased from 40.88%±9.45%to 67.86%±27.10%.The genera Pseudarthrobacter,Arenimonas,and Limnohabitans were effectively removed by chlorination,while Phreatobacter,Undibacterium,Pseudomonas,and Sphingomonas within the Proteobacteria phylum were greatly enriched after chlorination.Metagenomic analyses revealed the occurrence of 56 species of potential pathogenic bacteria within 17 genera in drinking water,mainly including Pseudomonas fluorescens and five mycobacteria species,which were also persistent in tap water samples.The bacteria were found to be involved in various pathways,among which considerable groups were related to human diseases,including infectious diseases and even cancers.

Study of pathogenic genes in a pedigree with familial dilated cardiomyopathy

BACKGROUND Dilated cardiomyopathy(DCM)is a genetically heterogeneous cardiac disorder characterized by left ventricular dilation and contractile dysfunction.The substantial genetic heterogeneity evident in patients with DCM contributes to variable disease severity and complicates overall prognosis,which can be very poor.AIM To identify pathogenic genes in DCM through pedigree analysis.METHODS Our research team identified a patient with DCM in the clinic.Through invest-igation,we found that the family of this patient has a typical DCM pedigree.High-throughput sequencing technology,next-generation sequencing,was used to sequence the whole exomes of seven samples in the pedigree.RESULTS A novel and potentially pathogenic gene mutation-ANK2p.F3067L-was discovered.The mutation was completely consistent with the clinical information for this DCM pedigree.Sanger sequencing was used to further verify the locus of the mutation in pedigree samples.These results were consistent with those of high-throughput sequencing.CONCLUSIONS ANK2p.F3067L is considered a novel and potentially pathogenic gene mutation in DCM.

Effects of ex situ conservation on diversity and function of the gut microbiota of the Tibetan wild ass(Equus kiang)

Ex situ conservation is the main method for the protection of endangered wildlife.To explore the effect of ex situ conservation on the gut microbiota of the kiang(Equus kiang),metagenomic sequencing combined with bioinformatics analysis was used to investigate the composition and function of the gut microbiota of the kiang.The results showed that ex situ conservation not only protected wildlife,but also affected the composition and function of gut microbiota,as well as the health of animals.In the zoo,the ratio of the relative abundance of Firmicutes to that of Bacteroidetes(F/B)is higher,clusters of potentially pathogenic bacteria(such as Catonella,Catonella,and Mycoplasma)are more numerous,the abundance of resistance genes is higher,and the abundance of metabolic functions is increased.The dynamic changes of the gut microbiota also played an important role in the nutritional absorption,energy metabolism,and environmental adaptation of the kiang.Improving the rearing environment and increasing food diversity play important roles for increasing the diversity of gut microbiota,reducing the spread of potentially pathogenic bacteria,and reducing diseases.In the wild,especially in winter and in food-deficient areas,food supplementation can enhance the gut microbial homeostasis of wild animals and reduce the impact of crises.In depth studies of the gut microbial function of wildlife have important implications for improving ex situ conservation.