Sergey Malanin

K19 capsular polysaccharide of Acinetobacter baumannii is produced via a Wzy polymerase encoded in a small genomic island rather than the KL19 capsule gene cluster.

Polymerization of the oligosaccharides (K units) of complex capsular polysaccharides (CPSs) requires a Wzy polymerase, which is usually encoded in the gene cluster that directs K unit synthesis. Here, a gene cluster at the Acinetobacter K locus (KL) that lacks a wzy gene, KL19, was found in Acinetobacter baumannii ST111 isolates 28 and RBH2 recovered from hospitals in the Russian Federation and Australia, respectively. However, these isolates produced long-chain capsule, and a wzy gene was found in a 6.1 kb genomic island (GI) located adjacent to the cpn60 gene. The GI also includes an acetyltransferase gene, atr25, which is interrupted by an insertion sequence (IS) in RBH2. The capsule structure from both strains was →3)-α-d-GalpNAc-(1→4)-α-d-GalpNAcA-(1→3)-β-d-QuipNAc4NAc-(1→, determined using NMR spectroscopy. Biosynthesis of the K unit was inferred to be initiated with QuiNAc4NAc, and hence the Wzy forms the β-(1→3) linkage between QuipNAc4NAc and GalpNAc. The GalpNAc residue is 6-O-acetylated in isolate 28 only, showing that atr25 is responsible for this acetylation. The same GI with or without an IS in atr25 was found in draft genomes of other KL19 isolates, as well as ones carrying a closely related CPS gene cluster, KL39, which differs from KL19 only in a gene for an acyltransferase in the QuiNAc4NR synthesis pathway. Isolates carrying a KL1 variant with the wzy and atr genes each interrupted by an ISAba125 also have this GI. To our knowledge, this study is the first report of genes involved in capsule biosynthesis normally found at the KL located elsewhere in A. baumannii genomes.

Links of gut microbiota composition with alcohol dependence syndrome and alcoholic liver disease

BackgroundAlcohol abuse has deleterious effects on human health by disrupting the functions of many organs and systems. Gut microbiota has been implicated in the pathogenesis of alcohol-related liver diseases, with its composition manifesting expressed dysbiosis in patients suffering from alcoholic dependence. Due to its inherent plasticity, gut microbiota is an important target for prevention and treatment of these diseases. Identification of the impact of alcohol abuse with associated psychiatric symptoms on the gut community structure is confounded by the liver dysfunction. In order to differentiate the effects of these two factors, we conducted a comparative “shotgun” metagenomic survey of 99 patients with the alcohol dependence syndrome represented by two cohorts—with and without liver cirrhosis. The taxonomic and functional composition of the gut microbiota was subjected to a multifactor analysis including comparison with the external control group.ResultsAlcoholic dependence and liver cirrhosis were associated with profound shifts in gut community structures and metabolic potential across the patients. The specific effects on species-level community composition were remarkably different between cohorts with and without liver cirrhosis. In both cases, the commensal microbiota was found to be depleted. Alcoholic dependence was inversely associated with the levels of butyrate-producing species from the Clostridiales order, while the cirrhosis—with multiple members of the Bacteroidales order. The opportunist pathogens linked to alcoholic dependence included pro-inflammatory Enterobacteriaceae, while the hallmarks of cirrhosis included an increase of oral microbes in the gut and more frequent occurrence of abnormal community structures. Interestingly, each of the two factors was associated with the expressed enrichment in many Bifidobacterium and Lactobacillus—but the exact set of the species was different between alcoholic dependence and liver cirrhosis. At the level of functional potential, the patients showed different patterns of increase in functions related to alcohol metabolism and virulence factors, as well as pathways related to inflammation.ConclusionsMultiple shifts in the community structure and metabolic potential suggest strong negative influence of alcohol dependence and associated liver dysfunction on gut microbiota. The identified differences in patterns of impact between these two factors are important for planning of personalized treatment and prevention of these pathologies via microbiota modulation. Particularly, the expansion of Bifidobacterium and Lactobacillus suggests that probiotic interventions for patients with alcohol-related disorders using representatives of the same taxa should be considered with caution. Taxonomic and functional analysis shows an increased propensity of the gut microbiota to synthesis of the toxic acetaldehyde, suggesting higher risk of colorectal cancer and other pathologies in alcoholics.

Draft Whole-Genome Sequence of Bacillus altitudinis Strain B-388, a Producer of Extracellular RNase

ABSTRACT Here, we present a draft genome sequence of Bacillus altitudinis strain B-388, including a putative plasmid. The strain was isolated from the intestine of Indian meal moth, a common pest of stored grains, and it is characterized by the production of extracellular RNase, similar to binase, which is of interest for comparative studies and biotechnology.

Data on gut metagenomes of the patients with alcoholic dependence syndrome and alcoholic liver cirrhosis

Alcoholism is associated with significant changes in gut microbiota composition. Metagenomic sequencing allows to assess the altered abundance levels of bacterial taxa and genes in a culture-independent way. We collected 99 stool samples from the patients with alcoholic dependence syndrome (n=72) and alcoholic liver cirrhosis (n=27). Each of the samples was surveyed using “shotgun” (whole-genome) sequencing on SOLiD platform. The reads are deposited in the ENA (project ID: PRJEB18041).

Shifts in the gut microbiota structure caused by Helicobacter pylori eradication therapy

The human gut microbiome plays an important role both in health and disease. The use of antibiotics can alter gut microbiota composition, which can cause complications of various kinds. Here we report a whole genome sequencing metagenomic study of the intestinal microbiota changes caused by Helicobacter pylori eradication therapy. We have found the decrease in taxonomic alpha-diversity due to the therapy. The changes observed were more extensive for patients with duodenal ulcer and female ones. As well across the patients under the therapy we have detected the shifts in the metabolic potential and resistome. Seven KEGG pathways associated with quorum sensing, genetic Information processing and environmental Information processing were increased, while metabolic pathways related with metabolism of cofactors and vitamins and glycan biosynthesis and metabolism decreased. Changes in the resistome profile have also been identified. We observed perturbations in intraspecies structures, which were higher in group of patients under the therapy than in control group of people without treatment. The Eubacterium rectale pangenome extracted from metagenomic data were changed. We also isolated and sequenced Enterococcus faecium strains from two patients before and after eradication therapy. After the therapy this bacterium increased as the antibiotic resistance in vitro, as well the number of ARGs to macrolides and tetracyclines and metagenomic relative abundance in comparison with strains before therapy. In summary, microbial community demonstrated shift to reduce metabolic potential and to increased mechanisms, which mediate more survival condition through intraspecies perturbations. Importance The human gut microbiome plays an important role both in health and disease. The use of antibiotics can alter gut microbiota composition, which can cause complications of various kinds. H. pylori eradication therapy causes multiple shifts and alterations (including intraspecies changes) of the intestinal microbiota structure and leads to the accumulation of genes which determine resistance to macrolides. Since these changes are not the same for patients with various diseases, patients with duodenal ulcer may be further paid special attention for reducing side effects, such as antibiotic-induced dysbiosis. Also, study of antibiotic treatment in terms of its impact upon the human gut microbiota allows shedding light on of the complex processes that cause accumulation and spread of antibiotic resistance. An identification and understanding of these complicated processes may help to constrain antibiotic resistance spread, which is of great importance for human health care.

Additional file 11: Table S10. of Links of gut microbiota composition with alcohol dependence syndrome and alcoholic liver disease

Gene groups related to alcohol metabolism differentially abundant in the metagenomes of ALC and ADS patients in comparison with the control group. The table contains the mean and the standard deviation of the relative abundance of KEGG Orthology Groups. (XLSX 9 kb)

The Influence of Helicobacter Pylori Eradication Therapy on Intestinal Microbiota

H. pylori eradication therapy including antibiotics as well as H. pylori itself can influence the normal intestinal microbiota content. The aim of the study was to describe the gut microbiota composition in H. pylori-positive and H. pylori-negative patients as well as the influence of eradication therapy on gut microbiota. 198 stool samples were taken for analysis: 74 samples from H. pylori-positive patients before eradication therapy, 74 from the same patients after eradication, 50 from H. pylori-negative patients (control group). Total DNA was isolated from the stool samples and subjected to whole-genome sequencing on SOLiD 5500 Wildfire platform. Intestinal microbiota was evaluated based on number of species, qualitative composition, Shannon diversity index and Bray-Curtis metrics. Results. Bacterial community was quite similar in all groups: Bacteroides, Prevotella, Eubacterium, Roseburia, Faecalibacterium and Clostridium genera were predominant in all samples. The spread in variations of the prevailing Firmicutes and Bacteroides phyla was wider after the treatment than in control samples. In about half of patients eradication therapy led to the decrease of both the number of species and the Shannon index indicating a decrease in the overall bacterial diversity with a possible predominance of individual species. Eradication therapy resulted in the reduction of the relative representation of Bifidobacterium, Collinsella, Coprococcus genera, accompanied with the increase of Clostridium, Bacteroides, Coprobacillus and Flavonifractor genera. Evaluation of taxonomic diversity changes based on Shannon index and Bray-Curtis metrics allows to differentiate patients into the groups with mild, moderate and severe changes. In 82% of cases mild and moderate changes in microbial community content were found increased level of Bacteroides genus, decreasing levels of Bifidobacterium and Eubacterium genus, simultaneously. Escherichia genus had the increased abundance in the majority of patients with severe microbial shifts after eradication therapy. Changes in the composition of intestinal microbiota after H. pylori eradication therapy depend mostly on the initial content of the intestinal microbiota: the closer initial microbial state of H. pylori-positive patients to the control samples is, the milder changes could be detected after eradication therapy. Gene-centric analysis of the functional composition in paired samples taken before and after therapy showed an increase of the relative abundance of genes conferring antibiotic resistance. Conclusions. Evaluation of intestinal microflora content prior to treatment can probably predict the incidence of side effects related to changes in microbial composition. This work was financially supported by the Ministry of Education and Science of Russian Federation (agreement #14.575.21.0076, ID RFMEFI575I4X0076).

Shotgun metagenomic data on the human stool samples to characterize shifts of the gut microbial profile after the Helicobacter pylori eradication therapy

The shotgun sequencing data presented in this report are related to the research article named “Gut microbiome shotgun sequencing in assessment of microbial community changes associated with H. pylori eradication therapy” (Khusnutdinova et al., 2016) [1]. Typically, the H. pylori eradication protocol includes a prolonged two-week use of the broad-spectrum antibiotics. The presented data on the whole-genome sequencing of the total DNA from stool samples of patients before the start of the eradication, immediately after eradication and several weeks after the end of treatment could help to profile the gut microbiota both taxonomically and functionally. The presented data together with those described in Glushchenko et al. (2017) [2] allow researchers to characterize the metagenomic profiles in which the use of antibiotics could result in dramatic changes in the intestinal microbiota composition. We perform 15 gut metagenomes from 5 patients with H. pylori infection, obtained through the shotgun sequencing on the SOLiD 5500 W platform. Raw reads are deposited in the ENA under project ID PRJEB21338.

Draft Genome Sequence of Agreia bicolorata Strain AC-1804, a Producer of Large Amounts of Carotenoid Pigments, Isolated from Narrow Reed Grass Infected by the Phytoparasitic Nematode

ABSTRACT Here, we report the draft genome sequence of Agreia bicolorata strain AC-1804, isolated from narrow reed grass galls induced by a plant-parasitic nematode which is able to produce large amounts of carotenoid pigments. The draft genome sequence of 3,919,485 bp provides a resource for carotenoid pathway research.