scholarly journals Improving Characterization of Understudied Human Microbiomes Using Targeted Phylogenetics

mSystems ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Bruce A. Rosa ◽  
Kathie Mihindukulasuriya ◽  
Kymberlie Hallsworth-Pepin ◽  
Aye Wollam ◽  
John Martin ◽  
...  

ABSTRACT Whole-genome bacterial sequences are required to better understand microbial functions, niche-specific bacterial metabolism, and disease states. Although genomic sequences are available for many of the human-associated bacteria from commonly tested body habitats (e.g., feces), as few as 13% of bacterium-derived reads from other sites such as the skin map to known bacterial genomes. To facilitate a better characterization of metagenomic shotgun reads from underrepresented body sites, we collected over 10,000 bacterial isolates originating from 14 human body habitats, identified novel taxonomic groups based on full-length 16S rRNA gene sequences, clustered the sequences to ensure that no individual taxonomic group was overselected for sequencing, prioritized bacteria from underrepresented body sites (such as skin and respiratory and urinary tracts), and sequenced and assembled genomes for 665 new bacterial strains. Here, we show that addition of these genomes improved read mapping rates of Human Microbiome Project (HMP) metagenomic samples by nearly 30% for the previously underrepresented phylum Fusobacteria, and 27.5% of the novel genomes generated here had high representation in at least one of the tested HMP samples, compared to 12.5% of the sequences in the public databases, indicating an enrichment of useful novel genomic sequences resulting from the prioritization procedure. As our understanding of the human microbiome continues to improve and to enter the realm of therapy developments, targeted approaches such as this to improve genomic databases will increase in importance from both an academic and a clinical perspective. IMPORTANCE The human microbiome plays a critically important role in health and disease, but current understanding of the mechanisms underlying the interactions between the varying microbiome and the different host environments is lacking. Having access to a database of fully sequenced bacterial genomes provides invaluable insights into microbial functions, but currently sequenced genomes for the human microbiome have largely come from a limited number of body sites (primarily feces), while other sites such as the skin, respiratory tract, and urinary tract are underrepresented, resulting in as little as 13% of bacterium-derived reads mapping to known bacterial genomes. Here, we sequenced and assembled 665 new bacterial genomes, prioritized from a larger database to select underrepresented body sites and bacterial taxa in the existing databases. As a result, we substantially improve mapping rates for samples from the Human Microbiome Project and provide an important contribution to human bacterial genomic databases for future studies.

2019 ◽  
Author(s):  
Bruce A Rosa ◽  
Kathie Mihindukulasuriya ◽  
Kymberlie Hallsworth-Pepin ◽  
Aye Wollam ◽  
John Martin ◽  
...  

AbstractWhole genome bacterial sequences are required to better understand microbial functions, niches-pecific bacterial metabolism, and disease states. Although genomic sequences are available for many of the human-associated bacteria from commonly tested body habitats (e.g. stool), as few as 13% of bacterial-derived reads from other sites such as the skin map to known bacterial genomes. To facilitate a better characterization of metagenomic shotgun reads from under-represented body sites, we collected over 10,000 bacterial isolates originating from 14 human body habitats, identified novel taxonomic groups based on full length 16S rRNA sequences, clustered the sequences to ensure that no individual taxonomic group was over-selected for sequencing, prioritized bacteria from under-represented body sites (such as skin, respiratory and urinary tract), and sequenced and assembled genomes for 665 new bacterial strains. Here we show that addition of these genomes improved read mapping rates of HMP metagenomic samples by nearly 30% for the previously under-represented phylum Fusobacteria, and 27.5% of the novel genomes generated here had high representation in at least one of the tested HMP samples, compared to 12.5% of the sequences in the public databases, indicating an enrichment of useful novel genomic sequences resulting from the prioritization procedure. As our understanding of the human microbiome continues to improve and to enter the realm of therapy developments, targeted approaches such as this to improve genomic databases will increase in importance from both an academic and clinical perspective.ImportanceThe human microbiome plays a critically important role in health and disease, but current understanding of the mechanisms underlying the interactions between the varying microbiome and the different host environments is lacking. Having access to a database of fully sequenced bacterial genomes provides invaluable insights into microbial functions, but currently sequenced genomes for the human microbiome have largely come from a limited number of body sites (primarily stool), while other sites such as the skin, respiratory tract and urinary tracts are under-represented, resulting in as little as 13% of bacterial-derived reads mapping to known bacterial genomes. Here, we sequenced and assembled 665 new bacterial genomes, prioritized from a larger database to select under-represented body sites and bacterial taxa in the existing databases. As a result, we substantially improve mapping rates for samples from the Human Microbiome Project and provide an important contribution to human bacterial genomic databases for future studies.


2017 ◽  
Author(s):  
Victoria Cepeda ◽  
Bo Liu ◽  
Mathieu Almeida ◽  
Christopher M. Hill ◽  
Sergey Koren ◽  
...  

ABSTRACTMetagenomic studies have primarily relied on de novo approaches for reconstructing genes and genomes from microbial mixtures. While database driven approaches have been employed in certain analyses, they have not been used in the assembly of metagenomes. Here we describe the first effective approach for reference-guided metagenomic assembly of low-abundance bacterial genomes that can complement and improve upon de novo metagenomic assembly methods. When combined with de novo assembly approaches, we show that MetaCompass can generate more complete assemblies than can be obtained by de novo assembly alone, and improve on assemblies from the Human Microbiome Project (over 2,000 samples).


2007 ◽  
Vol 57 (8) ◽  
pp. 1815-1818 ◽  
Author(s):  
Kiyoung Lee ◽  
Yoe-Jin Choo ◽  
Stephen J. Giovannoni ◽  
Jang-Cheon Cho

Gram-negative, facultatively aerobic, chemoheterotrophic, short rod-shaped marine bacterial strains HTCC2662T and HTCC2663, isolated from the Sargasso Sea by using a dilution-to-extinction culturing method, were investigated to determine their taxonomic position. Characterization of the two strains by phenotypic and phylogenetic analyses revealed that they belonged to the same species. The DNA G+C content of strain HTCC2662T was 58.4 mol% and the predominant cellular fatty acids were C18 : 1 ω7c (52.5 %), C16 : 0 2-OH (13.5 %) and C18 : 1 11-methyl ω7c (12.2 %). Phylogenetic analysis of the 16S rRNA gene sequences showed that the strains represented a distinct line of descent within the genus Ruegeria, with highest sequence similarities to Ruegeria atlantica DSM 5823T (97.2 %), Ruegeria lacuscaerulensis DSM 11314T (96.5 %) and Ruegeria pomeroyi DSM 15171T (95.6 %). Several phenotypic characteristics, including facultatively requiring NaCl and oxygen for growth, together with the cellular fatty acid composition, differentiated strain HTCC2662T from other members of the genus Ruegeria. Based on phenotypic, chemotaxonomic and phylogenetic traits, it is suggested that strains HTCC2662T and HTCC2663 represent a novel species of the genus Ruegeria, for which the name Ruegeria pelagia sp. nov. is proposed. The type strain is HTCC2662T (=KCCM 42378T=NBRC 102038T).


2022 ◽  
Vol 23 (1) ◽  
pp. 483
Author(s):  
Vasily A. Popkov ◽  
Anastasia A. Zharikova ◽  
Evgenia A. Demchenko ◽  
Nadezda V. Andrianova ◽  
Dmitry B. Zorov ◽  
...  

Uremic retention solutes are the compounds that accumulate in the blood when kidney excretory function is impaired. Some of these compounds are toxic at high concentrations and are usually known as “uremic toxins”. The cumulative detrimental effect of uremic toxins results in numerous health problems and eventually mortality during acute or chronic uremia, especially in end-stage renal disease. More than 100 different solutes increase during uremia; however, the exact origin for most of them is still debatable. There are three main sources for such compounds: exogenous ones are consumed with food, whereas endogenous ones are produced by the host metabolism or by symbiotic microbiota metabolism. In this article, we identify uremic retention solutes presumably of gut microbiota origin. We used database analysis to obtain data on the enzymatic reactions in bacteria and human organisms that potentially yield uremic retention solutes and hence to determine what toxins could be synthesized in bacteria residing in the human gut. We selected biochemical pathways resulting in uremic retention solutes synthesis related to specific bacterial strains and revealed links between toxin concentration in uremia and the proportion of different bacteria species which can synthesize the toxin. The detected bacterial species essential for the synthesis of uremic retention solutes were then verified using the Human Microbiome Project database. Moreover, we defined the relative abundance of human toxin-generating enzymes as well as the possibility of the synthesis of a particular toxin by the human metabolism. Our study presents a novel bioinformatics approach for the elucidation of the origin of both uremic retention solutes and uremic toxins and for searching for the most likely human microbiome producers of toxins that can be targeted and used for the therapy of adverse consequences of uremia.


Author(s):  
Natasha R.F. Novaes ◽  
Isabel C. M. Fensterseifer ◽  
José L. R. Martins ◽  
Osmar N. Silva

Forensic Science compounds many study areas in context of solving crimes, one of which is the forensic microbiology. Combined with genomic approaches, microbiology has shown strong performance in studies regarding the relationship between microorganisms present on human skin and environment. The Human Microbiome Project (HMP) has contributed significantly to characterization of microbial complexity and their connection to human being. The purpose of this work consists of a historical overview of scientific articles, demonstrating the growth and possibility of using skin microbiome in forensic identification. Studies about use of cutaneous microbiome in human identification, as well its forensic approaches, were looked into for writing of this review. Comparisons among cutaneous microbial communities and manipulated objects have been tested using 16S rRNA, as well as a thorough sequencing of the bacterial genome. From use of ecological measures of distance to genetic markers with nucleotide variants and predictive algorithms, research has shown promising results for advances in field of forensic identification. The development of metagenomic microbial panel markers, named hidSkinPlax for targeted sequencing has been designed and tested with great results. Research results show satisfactory potential in human identification by cutaneous microbiome and the possibility for contributive use in elucidating crimes.


Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4357
Author(s):  
Michal Styczynski ◽  
Agata Rogowska ◽  
Katarzyna Gieczewska ◽  
Maciej Garstka ◽  
Anna Szakiel ◽  
...  

Antarctic regions are characterized by low temperatures and strong UV radiation. This harsh environment is inhabited by psychrophilic and psychrotolerant organisms, which have developed several adaptive features. In this study, we analyzed two Antarctic bacterial strains, Planococcus sp. ANT_H30 and Rhodococcus sp. ANT_H53B. The physiological analysis of these strains revealed their potential to produce various biotechnologically valuable secondary metabolites, including surfactants, siderophores, and orange pigments. The genomic characterization of ANT_H30 and ANT_H53B allowed the identification of genes responsible for the production of carotenoids and the in silico reconstruction of the pigment biosynthesis pathways. The complex manual annotation of the bacterial genomes revealed the metabolic potential to degrade a wide variety of compounds, including xenobiotics and waste materials. Carotenoids produced by these bacteria were analyzed chromatographically, and we proved their activity as scavengers of free radicals. The quantity of crude carotenoid extracts produced at two temperatures using various media was also determined. This was a step toward the optimization of carotenoid production by Antarctic bacteria on a larger scale.


2007 ◽  
Vol 73 (19) ◽  
pp. 6214-6223 ◽  
Author(s):  
Alejandro Oceguera-Cervantes ◽  
Agustín Carrillo-García ◽  
Néstor López ◽  
Sandra Bolaños-Nuñez ◽  
M. Javier Cruz-Gómez ◽  
...  

ABSTRACT Two bacterial strains (BQ1 and BQ8) were isolated from decomposed soft foam. These were selected for their capacity to grow in a minimal medium (MM) supplemented with a commercial surface-coating polyurethane (PU) (Hydroform) as the carbon source (MM-PUh). Both bacterial strains were identified as Alicycliphilus sp. by comparative 16S rRNA gene sequence analysis. Growth in MM-PUh showed hyperbolic behavior, with BQ1 producing higher maximum growth (17.8 ± 0.6 mg·ml−1) than BQ8 (14.0 ± 0.6 mg·ml−1) after 100 h of culture. Nuclear magnetic resonance, Fourier transform infrared (IR) spectroscopy, and gas chromatography-mass spectrometry analyses of Hydroform showed that it was a polyester PU type which also contained N-methylpyrrolidone (NMP) as an additive. Alicycliphilus sp. utilizes NMP during the first stage of growth and was able to use it as the sole carbon and nitrogen source, with calculated K s values of about 8 mg·ml−1. Enzymatic activities related to PU degradation (esterase, protease, and urease activities) were tested by using differential media and activity assays in cell-free supernatants of bacterial cultures in MM-PUh. Induction of esterase activity in inoculated MM-PUh, but not that of protease or urease activities, was observed at 12 h of culture. Esterase activity reached its maximum at 18 h and was maintained at 50% of its maximal activity until the end of the analysis (120 h). The capacity of Alicycliphilus sp. to degrade PU was demonstrated by changes in the PU IR spectrum and by the numerous holes produced in solid PU observed by scanning electron microscopy after bacterial culture. Changes in the PU IR spectra indicate that an esterase activity is involved in PU degradation.


2011 ◽  
Vol 78 (2) ◽  
pp. 511-518 ◽  
Author(s):  
Yohei Watanabe ◽  
Fumiko Nagai ◽  
Masami Morotomi

ABSTRACTIsolation, cultivation, and characterization of the intestinal microorganisms are important for understanding the comprehensive physiology of the human gastrointestinal (GI) tract microbiota. Here, we isolated two novel bacterial strains, YIT 12067Tand YIT 12068, from the feces of healthy human adults. Phylogenetic analysis indicated that they belonged to the same species and were most closely related toPhascolarctobacterium faeciumACM 3679T, with 91.4% to 91.5% 16S rRNA gene sequence similarities, respectively. Substrate availability tests revealed that the isolates used only succinate; they did not ferment any other short-chain fatty acids or carbohydrates tested. When these strains were cocultured with the xylan-utilizing and succinate-producing bacteriumParaprevotella xylaniphilaYIT 11841T, in medium supplemented with xylan but not succinate, their cell numbers became 2 to 3 orders of magnitude higher than those of the monoculture; succinate became undetectable, and propionate was formed. Database analysis revealed that over 200 uncultured bacterial clones from the feces of humans and other mammals showed high sequence identity (>98.7%) to YIT 12067T. Real-time PCR analysis also revealed that YIT 12067T-like bacteria were present in 21% of human fecal samples, at an average level of 3.34 × 108cells/g feces. These results indicate that YIT 12067T-like bacteria are distributed broadly in the GI tract as subdominant members that may adapt to the intestinal environment by specializing to utilize the succinate generated by other bacterial species. The phylogenetic and physiological properties of YIT 12067Tand YIT 12068 suggest that these strains represent a novel species, which we have designatedPhascolarctobacterium succinatutenssp. nov.


Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Chang Liu ◽  
Meng-Xuan Du ◽  
Rexiding Abuduaini ◽  
Hai-Ying Yu ◽  
Dan-Hua Li ◽  
...  

Abstract Background In gut microbiome studies, the cultured gut microbial resource plays essential roles, such as helping to unravel gut microbial functions and host-microbe interactions. Although several major studies have been performed to elucidate the cultured human gut microbiota, up to 70% of the Unified Human Gastrointestinal Genome species have not been cultured to date. Large-scale gut microbial isolation and identification as well as availability to the public are imperative for gut microbial studies and further characterizing human gut microbial functions. Results In this study, we constructed a human Gut Microbial Biobank (hGMB; homepage: hgmb.nmdc.cn) through the cultivation of 10,558 isolates from 31 sample mixtures of 239 fresh fecal samples from healthy Chinese volunteers, and deposited 1170 strains representing 400 different species in culture collections of the International Depository Authority for long-term preservation and public access worldwide. Following the rules of the International Code of Nomenclature of Prokaryotes, 102 new species were characterized and denominated, while 28 new genera and 3 new families were proposed. hGMB represented over 80% of the common and dominant human gut microbial genera and species characterized from global human gut 16S rRNA gene amplicon data (n = 11,647) and cultured 24 “most-wanted” and “medium priority” taxa proposed by the Human Microbiome Project. We in total sequenced 115 genomes representing 102 novel taxa and 13 previously known species. Further in silico analysis revealed that the newly sequenced hGMB genomes represented 22 previously uncultured species in the Unified Human Gastrointestinal Genome (UHGG) and contributed 24 representatives of potentially “dark taxa” that had not been discovered by UHGG. The nonredundant gene catalogs generated from the hGMB genomes covered over 50% of the functionally known genes (KEGG orthologs) in the largest global human gut gene catalogs and approximately 10% of the “most wanted” functionally unknown proteins in the FUnkFams database. Conclusions A publicly accessible human Gut Microbial Biobank (hGMB) was established that contained 1170 strains and represents 400 human gut microbial species. hGMB expands the gut microbial resources and genomic repository by adding 102 novel species, 28 new genera, 3 new families, and 115 new genomes of human gut microbes.


2018 ◽  
Author(s):  
Qianqian Liu ◽  
Feizhou Zhu ◽  
Liyu Chen ◽  
Meihua Xu ◽  
Jianwei Chen ◽  
...  

The microbiota in the human gut is not only a complicated microecological system but also plays important roles in both health and disease. In order to understand the roles of these gut bacteria, we determined the distribution of microbiota in different regions of the gut by sequencing the 16S rRNA gene V4 region of the bacteria in the saliva, gastric juice, and stool of healthy individuals. The 16S rRNA gene V3-V5 region sequences of saliva and stool microbiota were obtained from Human Microbiome Project (HMP) and the V4 sequence was obtained from the V3-V5 sequences by a program designed by Perl language. We found that the microbiota of the gastric juice is more similar to those in the saliva rather than that in the stool. The frequency of some taxa was significantly different among the three groups with the Streptococcus, Veillonella, Oribacterium, Selenomonas, Actinomyces, and Granulicatella most abundant in the saliva; the Prevotella, Neisseria, Actinobacillus, Treponema, and Helicobacter most abundant in the gastric juice; and the Bacteroides, Parabacteroides, Faecalibacterium, Sutterella, Ruminococcus, Oscillospira and Phascolarctobacterium most abundant in the stool. In addition, results from PICRUSt analyses suggest that the functions of microbiota in the gastric juice are more similar as those in the saliva than in the stool. Moreover, we also found that the membrane transport of the microbiota in the saliva is higher than that in the stool and gastric juice. To our knowledge, this is the first comprehensive comparison of microbiota in the human oral cavity, stomach, and intestine.


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