scholarly journals Effect of Incubation Temperature on the Detection of Thermophilic Campylobacter Species from Freshwater Beaches, Nearby Wastewater Effluents, and Bird Fecal Droppings

2013 ◽  
Vol 79 (24) ◽  
pp. 7639-7645 ◽  
Author(s):  
Izhar U. H. Khan ◽  
Stephen Hill ◽  
Eva Nowak ◽  
Thomas A. Edge
Keyword(s):  
Surface Water ◽  
Large Scale ◽  
Incubation Temperature ◽  
Its Region ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
C 32 ◽  
Species Specific ◽  
Incubation Temperatures

ABSTRACTThis large-scale study compared incubation temperatures (37°C versus 42°C) to study the detection of thermophilicCampylobacterspecies, includingCampylobacter jejuni,C. coli, andC. lari, in various surface water samples and bird fecal droppings around Hamilton Harbor, Lake Ontario. The putative culture isolates obtained from incubation temperatures of 37 and 42°C were confirmed byCampylobactergenus- and species-specific triplex PCR assays targeting the 16S rRNA gene and the 16S-23S rRNA gene internal transcribed spacer (ITS) region. A total of 759 water, wastewater, and bird fecal dropping samples were tested. Positive amplification reactions for the genusCampylobacterwere found for 454 (60%) samples incubated at 37°C, compared to 258 (34%) samples incubated at 42°C.C. jejuni(16%) andC. lari(12%) were detected significantly more frequently at the 42°C incubation temperature than at 37°C (8% and 5%, respectively). In contrast, significantly higher rates ofC. coli(14%) and otherCampylobacterspp. (36%) were detected at the 37°C incubation temperature than at 42°C (8% and 7%, respectively). These results were consistent across surface water, wastewater, and bird fecal dropping samples. At times,Campylobacterspp. were recovered and detected at 37°C (3% forC. jejuni, 10% forC. coli, and 3% forC. lari) when the same samples incubated at 42°C were negative. A significantly higher rate of otherCampylobacterspp. was detected only at 37°C (32%) than only at 42°C (3%). These results indicate that incubation temperature can significantly influence the culturability and detection of thermophilic and other fastidiousCampylobacterspp. and that a comprehensive characterization of theCampylobacterspp. in surface water, wastewaters, or bird fecal droppings will require incubation at both 37 and 42°C.

scholarly journals Comparison of Genospecies and Antimicrobial Resistance Profiles of Isolates in the Acinetobacter calcoaceticus-Acinetobacter baumannii Complex from Various Clinical Specimens

2012 ◽  
Vol 56 (12) ◽  
pp. 6267-6271 ◽  
Author(s):  
Ni Tien ◽  
Bang-Jau You ◽  
Hui-Lan Chang ◽  
Hsiu-Shen Lin ◽  
Chin-Yi Lee ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Acinetobacter Baumannii ◽  
Restriction Analysis ◽  
Acinetobacter Calcoaceticus ◽  
Its Region ◽  
Clinical Isolates ◽  
23S Rrna ◽  
Rrna Gene ◽  
Genotype 3 ◽  
Content Type

ABSTRACTThis study was conducted to compare the prevalences of antimicrobial resistance profiles of clinical isolates in theAcinetobacter calcoaceticus-Acinetobacter baumanniicomplex from sterile and nonsterile sites and to further study the relationship of antimicrobial resistance profiles and genospecies by amplified rRNA gene restriction analysis (ARDRA). A total of 1,381 isolates were tested with 12 different antibiotics to show their antimicrobial susceptibility profiles. A total of 205 clinical isolates were further analyzed by ARDRA of the intergenic spacer (ITS) region of the 16S-23S rRNA gene. It was found that the overall percentage of isolates from nonsterile sites (urine, sputum, pus, or catheter tip) that were resistant to the 12 antibiotics tested was significantly higher than that of isolates from sterile sites (cerebrospinal fluid [CSF], ascites fluid, and bloodstream) (46% versus 22%;P< 0.05). After ARDRA, it was found that 97% of the 62 isolates resistant to all antibiotics tested were theA. baumanniigenospecies, which was identified in only 31% of the isolates susceptible to all antibiotics tested. More genospecies diversity was identified in the isolates susceptible to all antibiotics tested, including genospecies of 13TU (34%), genotype 3 (29%), andA. calcoaceticus(5%). Furthermore, as 91% (10/11) of the isolates from CSF were susceptible to all antibiotics tested, theA. calcoaceticus-A. baumanniicomplex isolates with multidrug resistance could be less invasive than the more susceptible isolates. This study also indicated current emergence of carbapenem-, fluoroquinolone-, aminoglycoside-, and cephalosporin-resistantA. calcoaceticus-A. baumanniicomplex isolates in Taiwan.

scholarly journals Whole-Genome Phylogenomic Heterogeneity of Neisseria gonorrhoeae Isolates with Decreased Cephalosporin Susceptibility Collected in Canada between 1989 and 2013

2014 ◽  
Vol 53 (1) ◽  
pp. 191-200 ◽  
Author(s):  
Walter Demczuk ◽  
Tarah Lynch ◽  
Irene Martin ◽  
Gary Van Domselaar ◽  
Morag Graham ◽  
...  
Keyword(s):  
Neisseria Gonorrhoeae ◽  
Large Scale ◽  
Epidemiological Studies ◽  
23S Rrna ◽  
Genome Comparison ◽  
Whole Genome ◽  
Content Type ◽  
Genomic Epidemiology ◽  
High Level ◽  
Sequence Types

A large-scale, whole-genome comparison of CanadianNeisseria gonorrhoeaeisolates with high-level cephalosporin MICs was used to demonstrate a genomic epidemiology approach to investigate strain relatedness and dynamics. Although current typing methods have been very successful in tracing short-chain transmission of gonorrheal disease, investigating the temporal evolutionary relationships and geographical dissemination of highly clonal lineages requires enhanced resolution only available through whole-genome sequencing (WGS). Phylogenomic cluster analysis grouped 169 Canadian strains into 12 distinct clades. While someN. gonorrhoeaemultiantigen sequence types (NG-MAST) agreed with specific phylogenomic clades or subclades, other sequence types (ST) and closely related groups of ST were widely distributed among clades. Decreased susceptibility to extended-spectrum cephalosporins (ESC-DS) emerged among a group of diverse strains in Canada during the 1990s with a variety of nonmosaicpenAalleles, followed in 2000/2001 with thepenAmosaic X allele and then in 2007 with ST1407 strains with thepenAmosaic XXXIV allele. Five genetically distinct ESC-DS lineages were associated withpenAmosaic X, XXXV, and XXXIV alleles and nonmosaic XII and XIII alleles. ESC-DS with coresistance to azithromycin was observed in 5 strains with 23S rRNA C2599T or A2143G mutations. As the costs associated with WGS decline and analysis tools are streamlined, WGS can provide a more thorough understanding of strain dynamics, facilitate epidemiological studies to better resolve social networks, and improve surveillance to optimize treatment for gonorrheal infections.

scholarly journals Multipartner Symbiosis across Biological Domains: Looking at the Eukaryotic Associations from a Microbial Perspective

mSystems ◽  
2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Marta Turon ◽  
Maria J. Uriz ◽  
Daniel Martin
Keyword(s):  
Bacterial Communities ◽  
High Throughput Sequencing ◽  
Marine Invertebrates ◽  
Single Species ◽  
Rrna Gene ◽  
Polychaete Species ◽  
Content Type ◽  
Symbiotic Relationships ◽  
Host Sponge ◽  
Species Specific

ABSTRACTSponges establish tight associations with both micro- and macroorganisms. However, while studies on sponge microbiomes are numerous, nothing is currently known about the microbiomes of sponge-associated polychaetes and their relationships with those of their host sponges. We analyzed the bacterial communities of symbiotic polychaetes (Haplosyllisspp.) and their host sponges (Clathria reinwardti,Amphimedon paraviridis,Neofibularia hartmani, andAaptos suberitoides) to assess the influence of the sponges on the polychaete microbiomes. We identified both eukaryote partners by molecular (16S and COI genes) and morphological features, and we identified their microbial communities by high-throughput sequencing of the 16S rRNA gene (V4 region). We unravel the existence of sixHaplosyllisspecies (five likely undescribed) associated at very high densities with the study sponge species in Nha Trang Bay (central Vietnam). A single polychaete species inhabitedA. paraviridisand was different from the single species that inhabitedA. suberitoides. Conversely, two different polychaete species were found inC. reinwardtiandN. hartmani, depending on the two host locations. Regardless of the host sponge, polychaete microbiomes were species specific, which is a widespread feature in marine invertebrates. More than half of the polychaete bacteria were also found in the host sponge microbiome but at contrasting abundances. Thus, the associated polychaetes seemed to be able to select, incorporate, and enrich part of the sponge microbiome, a selection that appears to be polychaete species specific. Moreover, the bacterial diversity is similar in both eukaryotic partners, which additionally confirms the influence of food (host sponge) on the structure of the polychaete microbiome.IMPORTANCEThe symbiotic lifestyle represents a fundamental cryptic contribution to the diversity of marine ecosystems. Sponges are ideal targets to improve understanding the symbiotic relationships from evolutionary and ecological points of view, because they are the most ancient metazoans on earth, are ubiquitous in the marine benthos, and establish complex symbiosis with both prokaryotes and animals, which in turn also harbor their own bacterial communities. Here, we study the microbiomes of sponge-polychaete associations and confirm that polychaetes feed on their host sponges. The study worms select and enrich part of the sponge microbiome to shape their own species-specific bacterial communities. Moreover, worm microbiome diversity runs parallel to that of its food host sponge. Considering our results on symbiotic polychaetes and previous studies on fishes and mammals, diet appears to be an important source of bacteria for animals to shape their species-specific microbiomes.

scholarly journals Recommendations To Address the Difficulties Encountered When Determining Linezolid Resistance from Whole-Genome Sequencing Data

2018 ◽  
Vol 62 (8) ◽  
Author(s):  
Alicia G. Beukers ◽  
Henrik Hasman ◽  
Kristin Hegstad ◽  
Sebastiaan J. van Hal
Keyword(s):  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
23S Rrna ◽  
Whole Genome Sequencing Data ◽  
Rrna Gene ◽  
Whole Genome ◽  
Sequencing Data ◽  
Content Type ◽  
Numbering System ◽  
Linezolid Resistance

ABSTRACT Mutations associated with linezolid resistance within the V domain of 23S rRNA are annotated using an Escherichia coli numbering system. The 23S rRNA gene varies in length, nucleotide sequence, and copy number among bacterial species. Consequently, this numbering system is not intuitive and can lead to confusion when mutation sites are being located using whole-genome sequencing data. Using the mutation G2576T as an example, we demonstrate the difficulties associated with using the E. coli numbering system.

scholarly journals Mobile Elements in a Single-Filament Orange Guaymas Basin Beggiatoa (“Candidatus Maribeggiatoa”) sp. Draft Genome: Evidence for Genetic Exchange with Cyanobacteria

2013 ◽  
Vol 79 (13) ◽  
pp. 3974-3985 ◽  
Author(s):  
Barbara J. MacGregor ◽  
Jennifer F. Biddle ◽  
Andreas Teske
Keyword(s):  
Gulf Of California ◽  
Bacterial Species ◽  
Draft Genome ◽  
Genetic Exchange ◽  
23S Rrna ◽  
Rrna Gene ◽  
Homing Endonucleases ◽  
Guaymas Basin ◽  
Content Type ◽  
Group I

ABSTRACTThe draft genome sequence of a single orangeBeggiatoa(“CandidatusMaribeggiatoa”) filament collected from a microbial mat at a hydrothermal site in Guaymas Basin (Gulf of California, Mexico) shows evidence of extensive genetic exchange with cyanobacteria, in particular for sensory and signal transduction genes. A putative homing endonuclease gene and group I intron within the 23S rRNA gene; several group II catalytic introns; GyrB and DnaE inteins, also encoding homing endonucleases; multiple copies of sequences similar to thefdxNexcision elements XisH and XisI (required for heterocyst differentiation in some cyanobacteria); and multiple sequences related to an open reading frame (ORF) (00024_0693) of unknown function all have close non-Beggiatoaceaematches with cyanobacterial sequences. Sequences similar to the uncharacterized ORF and Xis elements are found in otherBeggiatoaceaegenomes, a variety of cyanobacteria, and a few phylogenetically dispersed pleiomorphic or filamentous bacteria. We speculate that elements shared among filamentous bacterial species may have been exchanged in microbial mats and that some of them may be involved in cell differentiation.

scholarly journals Correlating Microbial Diversity Patterns with Geochemistry in an Extreme and Heterogeneous Environment of Mine Tailings

2014 ◽  
Vol 80 (12) ◽  
pp. 3677-3686 ◽  
Author(s):  
Jun Liu ◽  
Zheng-Shuang Hua ◽  
Lin-Xing Chen ◽  
Jia-Liang Kuang ◽  
Sheng-Jin Li ◽  
...  
Keyword(s):  
Microbial Diversity ◽  
Community Composition ◽  
Environmental Conditions ◽  
Mine Tailings ◽  
Large Scale ◽  
Hot Springs ◽  
Mine Drainage ◽  
Rrna Gene ◽  
Content Type ◽  
Geochemical Parameters

ABSTRACTRecent molecular surveys have advanced our understanding of the forces shaping the large-scale ecological distribution of microbes in Earth's extreme habitats, such as hot springs and acid mine drainage. However, few investigations have attempted dense spatial analyses of specific sites to resolve the local diversity of these extraordinary organisms and how communities are shaped by the harsh environmental conditions found there. We have applied a 16S rRNA gene-targeted 454 pyrosequencing approach to explore the phylogenetic differentiation among 90 microbial communities from a massive copper tailing impoundment generating acidic drainage and coupled these variations in community composition with geochemical parameters to reveal ecological interactions in this extreme environment. Our data showed that the overall microbial diversity estimates and relative abundances of most of the dominant lineages were significantly correlated with pH, with the simplest assemblages occurring under extremely acidic conditions and more diverse assemblages associated with neutral pHs. The consistent shifts in community composition along the pH gradient indicated that different taxa were involved in the different acidification stages of the mine tailings. Moreover, the effect of pH in shaping phylogenetic structure within specific lineages was also clearly evident, although the phylogenetic differentiations within theAlphaproteobacteria,Deltaproteobacteria, andFirmicuteswere attributed to variations in ferric and ferrous iron concentrations. Application of the microbial assemblage prediction model further supported pH as the major factor driving community structure and demonstrated that several of the major lineages are readily predictable. Together, these results suggest that pH is primarily responsible for structuring whole communities in the extreme and heterogeneous mine tailings, although the diverse microbial taxa may respond differently to various environmental conditions.

scholarly journals Neisseria oralis sp. nov., isolated from healthy gingival plaque and clinical samples

2013 ◽  
Vol 63 (Pt_4) ◽  
pp. 1323-1328 ◽  
Author(s):  
William J. Wolfgang ◽  
Teresa V. Passaretti ◽  
Reashma Jose ◽  
Jocelyn Cole ◽  
An Coorevits ◽  
...  
Keyword(s):  
Type Strain ◽  
Type Species ◽  
Novel Species ◽  
Sequence Similarity ◽  
23S Rrna ◽  
Clinical Samples ◽  
Rrna Gene ◽  
The Novel ◽  
Content Type ◽  
Link Type

A polyphasic analysis was undertaken of seven independent isolates of Gram-negative cocci collected from pathological clinical samples from New York, Louisiana, Florida and Illinois and healthy subgingival plaque from a patient in Virginia, USA. The 16S rRNA gene sequence similarity among these isolates was 99.7–100 %, and the closest species with a validly published name was Neisseria lactamica (96.9 % similarity to the type strain). DNA–DNA hybridization confirmed that these isolates are of the same species and are distinct from their nearest phylogenetic neighbour, N. lactamica . Phylogenetic analysis of 16S and 23S rRNA gene sequences indicated that the novel species belongs in the genus Neisseria . The predominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C18 : 1ω7c. The cellular fatty acid profile, together with other phenotypic characters, further supports the inclusion of the novel species in the genus Neisseria . The name Neisseria oralis sp. nov. (type strain 6332T  = DSM 25276T  = LMG 26725T) is proposed.

scholarly journals Clostridium huakuii sp. nov., an anaerobic, acetogenic bacterium isolated from methanogenic consortia

2014 ◽  
Vol 64 (Pt_12) ◽  
pp. 4027-4032 ◽  
Author(s):  
Zhiyong Ruan ◽  
Yanwei Wang ◽  
Chi Zhang ◽  
Jinlong Song ◽  
Yi Zhai ◽  
...  
Keyword(s):  
Type Species ◽  
Large Scale ◽  
Rrna Gene ◽  
Respiratory Quinone ◽  
Content Type ◽  
Link Type ◽  
Gram Staining ◽  
Acetogenic Bacterium ◽  
Clostridium Subterminale ◽  
The 16S Rrna Gene

A Gram-staining-positive, spore-forming, obligately anaerobic, acetogenic bacterium, designated LAM1030T, was isolated from methanogenic consortia enriched from biogas slurry collected from the large-scale anaerobic digester of Modern Farming Corporation in Hebei Province, China. Cells of strain LAM1030T were motile, straight or spiral-rod-shaped. Strain LAM1030T could utilize glucose, fructose, maltose, galactose, lactose, sucrose, cellobiose, mannitol, pyruvate, succinic acid and tryptophan as the sole carbon source. Acetic acid, isovaleric acid and butanoic acid were the main products of glucose fermentation. Sodium sulfite was used as an electron acceptor. Growth of strain LAM1030T was completely inhibited by the addition of ampicillin, tetracycline, gentamicin or erythromycin at a concentration of 20 µg ml−1. The main polar lipids of strain LAM1030T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, 11 unknown glycolipids and two unknown phospholipids. No respiratory quinone was detected. The major fatty acids of strain LAM1030T were C16 : 0 (21.1 %), C14 : 0 (10.3 %), summed feature 9 (including C16:0 10-methyl and/or iso-C17:1 ω9c) (11.3% ), summed feature 3 (including C16:1 ω7c and/or C16:1 ω6c) (10.6% ) and iso-C15 : 0 (6.6 %). Analysis of the 16S rRNA gene sequence indicated that strain LAM1030T belonged to the genus Clostridium and was most closely related to Clostridium subterminale DSM 6970T, Clostridium thiosulfatireducens DSM 13105T and Clostridium sulfidigenes DSM 18982T, with 97.0, 96.9 and 96.8 % similarity, respectively. The G+C content of the genomic DNA of strain LAM1030T was 31.2±0.3 mol%. On the basis of its phenotypic, phylogenetic and chemotaxonomic characterization, strain LAM1030T is suggested to represent a novel species of the genus Clostridium , for which the name Clostridium huakuii sp. nov. is proposed. The type strain is LAM1030T ( = ACCC 00698T = JCM 19186T).

scholarly journals Genome sequence analyses show that Neisseria oralis is the same species as ‘ Neisseria mucosa var. heidelbergensis’

2013 ◽  
Vol 63 (Pt_10) ◽  
pp. 3920-3926 ◽  
Author(s):  
Julia S. Bennett ◽  
Keith A. Jolley ◽  
Martin C. J. Maiden
Keyword(s):  
Genome Sequence ◽  
Type Species ◽  
Whole Genome Sequence ◽  
23S Rrna ◽  
Rrna Gene ◽  
Whole Genome ◽  
Content Type ◽  
Link Type ◽  
The Family ◽  
Neisseria Mucosa

Phylogenies generated from whole genome sequence (WGS) data provide definitive means of bacterial isolate characterization for typing and taxonomy. The species status of strains recently defined with conventional taxonomic approaches as representing Neisseria oralis was examined by the analysis of sequences derived from WGS data, specifically: (i) 53 Neisseria ribosomal protein subunit (rps) genes (ribosomal multi-locus sequence typing, rMLST); and (ii) 246 Neisseria core genes (core genome MLST, cgMLST). These data were compared with phylogenies derived from 16S and 23S rRNA gene sequences, demonstrating that the N. oralis strains were monophyletic with strains described previously as representing ‘ Neisseria mucosa var. heidelbergensis’ and that this group was of equivalent taxonomic status to other well-described species of the genus Neisseria . Phylogenetic analyses also indicated that Neisseria sicca and Neisseria macacae should be considered the same species as Neisseria mucosa and that Neisseria flavescens should be considered the same species as Neisseria subflava . Analyses using rMLST showed that some strains currently defined as belonging to the genus Neisseria were more closely related to species belonging to other genera within the family; however, whole genome analysis of a more comprehensive selection of strains from within the family Neisseriaceae would be necessary to confirm this. We suggest that strains previously identified as representing ‘ N. mucosa var. heidelbergensis’ and deposited in culture collections should be renamed N. oralis . Finally, one of the strains of N. oralis was able to ferment lactose, due to the presence of β-galactosidase and lactose permease genes, a characteristic previously thought to be unique to Neisseria lactamica , which therefore cannot be thought of as diagnostic for this species; however, the rMLST and cgMLST analyses confirm that N. oralis is most closely related to N. mucosa .

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