scholarly journals Cultivation-Dependant Assessment, Diversity, and Ecology of Haloalkaliphilic Bacteria in Arid Saline Systems of Southern Tunisia

2013 ◽  
Vol 2013 ◽  
pp. 1-15 ◽  
Author(s):  
Darine El Hidri ◽  
Amel Guesmi ◽  
Afef Najjari ◽  
Hanen Cherif ◽  
Besma Ettoumi ◽  
...  
Keyword(s):  
16S Rrna ◽  
Internal Transcribed Spacers ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Ecological Niches ◽  
Desert Plant ◽  
Gram Positive ◽  
Southern Tunisia ◽  
Haloalkaliphilic Bacteria

Haloalkaliphiles are polyextremophiles adapted to grow at high salt concentrations and alkaline pH values. In this work, we isolated 122 haloalkaliphilic bacteria upon enrichments of 23 samples from 5 distinct saline systems of southern Tunisia, growing optimally in media with 10% salt and at pH 10. The collection was classified into 44 groups based on the amplification of the 16S–23S rRNA internal transcribed spacers (ITS-PCR). Phylogenetic analysis and sequencing of the 16S rRNA genes allowed the identification of 13 genera and 20 distinct species. Three gram-positive isolates showing between 95 and 96% of 16S rRNA sequence homology with Bacillus saliphilus could represent new species or genus. Beside the difference in bacterial diversity between the studied sites, several species ecological niches correlations were demonstrated such asOceanobacillusin salt crust,Nesterenkoniain sand, andSalinicoccusin the rhizosphere of the desert plantSalicornia. The collection was further evaluated for the production of extracellular enzymes. Activity tests showed that gram-positive bacteria were mostly active, particularly for protease, lipase, DNase, and amylase production. Our overall results demonstrate the huge phenotypic and phylogenetic diversity of haloalkaliphiles in saline systems of southern Tunisia which represent a valuable source of new lineages and metabolites.

scholarly journals Cultivation-Independent Examination of Horizontal Transfer and Host Range of an IncP-1 Plasmid among Gram-Positive and Gram-Negative Bacteria Indigenous to the Barley Rhizosphere

2006 ◽  
Vol 72 (10) ◽  
pp. 6687-6692 ◽  
Author(s):  
Sanin Musovic ◽  
Gunnar Oregaard ◽  
Niels Kroer ◽  
Søren J. Sørensen
Keyword(s):  
16S Rrna ◽  
Host Range ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Gram Positive ◽  
Gram Negative ◽  
Indigenous Bacteria ◽  
Transfer Frequency

ABSTRACTThe host range and transfer frequency of an IncP-1 plasmid (pKJK10) among indigenous bacteria in the barley rhizosphere was investigated. A new flow cytometry-based cultivation-independent method for enumeration and sorting of transconjugants for subsequent 16S rRNA gene classification was used. Indigenous transconjugant rhizosphere bacteria were collected by fluorescence-activated cell sorting and identified by cloning and sequencing of 16S rRNA genes from the sorted cells. The host range of the pKJK10 plasmid was exceptionally broad, as it included not only bacteria belonging to the alpha, beta, and gamma subclasses of theProteobacteria, but alsoArthrobactersp., a gram-positive member of theActinobacteria. The transfer frequency (transconjugants per donor) from thePseudomonas putidadonor to the indigenous bacteria was 7.03 × 10−2± 3.84 × 10−2. This is the first direct documentation of conjugal transfer between gram-negative donor and gram-positive recipient bacteria in situ.

scholarly journals Phylogenetic relationships within the family Halomonadaceae based on comparative 23S and 16S rRNA gene sequence analysis

2010 ◽  
Vol 60 (4) ◽  
pp. 737-748 ◽  
Author(s):  
Rafael R. de la Haba ◽  
David R. Arahal ◽  
M. Carmen Márquez ◽  
Antonio Ventosa
Keyword(s):  
16S Rrna ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Rrna Gene ◽  
Gene Sequences ◽  
The Family ◽  
23S Rrna Gene ◽  
Group 2 ◽  
Group 1

A phylogenetic study of the family Halomonadaceae was carried out based on complete 16S rRNA and 23S rRNA gene sequences. Several 16S rRNA genes of type strains were resequenced, and 28 new sequences of the 23S rRNA gene were obtained. Currently, the family includes nine genera (Carnimonas, Chromohalobacter, Cobetia, Halomonas, Halotalea, Kushneria, Modicisalibacter, Salinicola and Zymobacter). These genera are phylogenetically coherent except Halomonas, which is polyphyletic. This genus comprises two clearly distinguished clusters: group 1 includes Halomonas elongata (the type species) and the species Halomonas eurihalina, H. caseinilytica, H. halmophila, H. sabkhae, H. almeriensis, H. halophila, H. salina, H. organivorans, H. koreensis, H. maura and H. nitroreducens. Group 2 comprises the species Halomonas aquamarina, H. meridiana, H. axialensis, H. magadiensis, H. hydrothermalis, H. alkaliphila, H. venusta, H. boliviensis, H. neptunia, H. variabilis, H. sulfidaeris, H. subterranea, H. janggokensis, H. gomseomensis, H. arcis and H. subglaciescola. Halomonas salaria forms a cluster with Chromohalobacter salarius and the recently described genus Salinicola, and their taxonomic affiliation requires further study. More than 20 Halomonas species are phylogenetically not within the core constituted by the Halomonas sensu stricto cluster (group 1) or group 2 and, since their positions on the different phylogenetic trees are not stable, they cannot be recognized as additional groups either. In general, there is excellent agreement between the phylogenies based on the two rRNA gene sequences, but the 23S rRNA gene showed higher resolution in the differentiation of species of the family Halomonadaceae.

scholarly journals rDNA analyses of planktonic heterocystous cyanobacteria, including members of the genera Anabaenopsis and Cyanospira The GenBank accession numbers of the 16S rDNA gene sequences reported in this paper are AY038032–AY038037.

Microbiology ◽  
2002 ◽  
Vol 148 (2) ◽  
pp. 481-496 ◽  
Author(s):  
Isabelle Iteman ◽  
Rosmarie Rippka ◽  
Nicole Tandeau de Marsac ◽  
Michael Herdman
Keyword(s):  
16S Rrna ◽  
16S Rdna ◽  
Genomic Sequence ◽  
Sequence Similarity ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Phylogenetic Position ◽  
Rrna Gene ◽  
Heterocystous Cyanobacteria

The taxonomic coherence and phylogenetic relationships of 11 planktonic heterocystous cyanobacterial isolates were examined by investigating two areas of the rRNA operon, the 16S rRNA gene (rrnS) and the internal transcribed spacer (ITS) located between the 16S rRNA and 23S rRNA genes. The rrnS sequences were determined for five strains, including representatives of Anabaena flos-aquae, Aphanizomenon flos-aquae, Nodularia sp. and two alkaliphilic planktonic members of the genera Anabaenopsis and Cyanospira, whose phylogenetic position was previously unknown. Comparison of the data with those previously published for individual groups of planktonic heterocystous cyanobacteria showed that, with the exception of members assigned to the genus Cylindrospermopsis, all the planktonic strains form a distinct subclade within the monophyletic clade of heterocystous cyanobacteria. Within this subclade five different phylogenetic clusters were distinguished. The phylogenetic groupings of Anabaena and Aphanizomenon strains within three of these clusters were not always consistent with their generic or specific assignments based on classical morphological definitions, and the high degree of sequence similarity between strains of Anabaenopsis and Cyanospira suggests that they may be assignable to a single genus. Ribotyping and additional studies performed on PCR amplicons of the 16S rDNA or the ITS for the 11 planktonic heterocystous strains demonstrated that they all contain multiple rrn operons and ITS regions of variable size. Finally, evidence is provided for intra-genomic sequence heterogeneity of the 16S rRNA genes within most of the individual isolates.

scholarly journals Mycoplasma anserisalpingitidis sp. nov., isolated from European domestic geese (Anser anser domesticus) with reproductive pathology

2020 ◽  
Vol 70 (4) ◽  
pp. 2369-2381 ◽  
Author(s):  
Dmitriy V. Volokhov ◽  
Dénes Grózner ◽  
Miklós Gyuranecz ◽  
Naola Ferguson-Noel ◽  
Yamei Gao ◽  
...  
Keyword(s):  
16S Rrna ◽  
Type Strain ◽  
Type Species ◽  
Novel Species ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type

In 1983, Mycoplasma sp. strain 1220 was isolated in Hungary from the phallus lymph of a gander with phallus inflammation. Between 1983 and 2017, Mycoplasma sp. 1220 was also identified and isolated from the respiratory tract, liver, ovary, testis, peritoneum and cloaca of diseased geese in several countries. Seventeen studied strains produced acid from glucose and fructose but did not hydrolyse arginine or urea, and all grew under aerobic, microaerophilic and anaerobic conditions at 35 to 37 ˚C in either SP4 or pleuropneumonia-like organism medium supplemented with glucose and serum. Colonies on agar showed a typical fried-egg appearance and transmission electron microscopy revealed a typical mycoplasma cellular morphology. Molecular characterization included analysis of the following genetic loci: 16S rRNA, 23S rRNA, 16S–23S rRNA ITS, rpoB, rpoC, rpoD, uvrA, parC, topA, dnaE, fusA and pyk. The genome was sequenced for type strain 1220T. The 16S rRNA gene sequences of studied strains of Mycoplasma sp. 1220 shared 99.02–99.19 % nucleotide similarity with M. anatis strains but demonstrated ≤95.00–96.70 % nucleotide similarity to the 16S rRNA genes of other species of the genus Mycoplasma . Phylogenetic, average nucleotide and amino acid identity analyses revealed that the novel species was most closely related to Mycoplasma anatis . Based on the genetic data, we propose a novel species of the genus Mycoplasma , for which the name Mycoplasma anserisalpingitidis sp. nov. is proposed with the type strain 1220T (=ATCC BAA-2147T=NCTC 13513T=DSM 23982T). The G+C content is 26.70 mol%, genome size is 959110 bp.

scholarly journals Reassessment of the phylogenetic relationships of Thiomonas cuprina

2007 ◽  
Vol 57 (11) ◽  
pp. 2720-2724 ◽  
Author(s):  
Donovan P. Kelly ◽  
Yoshihito Uchino ◽  
Harald Huber ◽  
Ricardo Amils ◽  
Ann P. Wood
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Rrna Gene ◽  
Significant Similarity ◽  
23S Rrna Gene ◽  
The 16S Rrna Gene

The published sequence of the 16S rRNA gene of Thiomonas cuprina strain Hö5 (=DSM 5495T) (GenBank accession no. U67162) was found to be erroneous. The 16S rRNA genes from the type strain held by the DSMZ since 1990 (DSM 5495T =NBRC 102145T) and strain Hö5 maintained frozen in the Universität Regensburg for 23 years (=NBRC 102094) were sequenced and found to be identical, but to show no significant similarity to the U67162 sequence. This also casts some doubt on the previously published 5S and 23S rRNA gene sequences (GenBank accession nos U67171 and X75567). The correct 16S rRNA gene sequence showed 99.8 % identity to those from Thiomonas delicata NBRC 14566T and ‘Thiomonas arsenivorans’ DSM 16361. The properties of these three species are re-evaluated, and emended descriptions are provided for the genus Thiomonas and the species Thiomonas cuprina.

scholarly journals Relationships of Bradyrhizobia from the LegumesApios americana and Desmodium glutinosum

1999 ◽  
Vol 65 (11) ◽  
pp. 4914-4920 ◽  
Author(s):  
Matthew A. Parker
Keyword(s):  
16S Rrna ◽  
Root Nodule ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Enzyme Electrophoresis ◽  
Nodule Bacteria ◽  
Root Nodule Bacteria ◽  
Rrna Sequences ◽  
16S Rrna Sequences

ABSTRACT Multilocus enzyme electrophoresis, partial 23S rRNA sequences, and nearly full-length 16S rRNA sequences all indicated high genetic similarity among root-nodule bacteria associated with Apios americana, Desmodium glutinosum, andAmphicarpaea bracteata, three common herbaceous legumes whose native geographic ranges in eastern North America overlap extensively. A total of 19 distinct multilocus genotypes (electrophoretic types [ETs]) were found among the 35 A. americana and 33 D. glutinosum isolates analyzed. Twelve of these ETs (representing 78% of all isolates) were either identical to ETs previously observed in A. bracteatapopulations, or differed at only one locus. Within both 23S and 16S rRNA genes, several isolates from A. americana and D. glutinosum were either identical to A. bracteataisolates or showed only single nucleotide differences. Growth rates and nitrogenase activities of A. bracteata plants inoculated with isolates from D. glutinosum were equivalent to levels found with native A. bracteata bacterial isolates, but none of the three A. americana isolates tested had high symbiotic effectiveness on A. bracteata. Phylogenetic analysis of both 23S and 16S rRNA sequences indicated that bothA. americana and D. glutinosum harbored rare bacterial genotypes similar to Bradyrhizobium japonicumUSDA 110. However, the predominant root nodule bacteria on both legumes were closely related to Bradyrhizobium elkanii.

scholarly journals Comparative Study of PCR-Based Approaches for the Genetic Characterization of Three Strains of Acidithiobacillus caldus Isolated from Different Sites in China

2013 ◽  
Vol 62 (4) ◽  
pp. 351-358
Author(s):  
Xueling Wu ◽  
Hong Duan ◽  
Hongwei Fan ◽  
Zhenzhen Zhang ◽  
Lili Liu
Keyword(s):  
16S Rrna ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Rrna Gene ◽  
Sequencing Analysis ◽  
Intergenic Spacers ◽  
Acidithiobacillus Caldus ◽  
Pcr Fingerprinting ◽  
23S Rrna Gene

Comparative study of the genetic characteristics among three Acidithiobacillus caldus strains isolated from different typical environments in China was performed using a combination of molecular methods, namely sequencing analysis of PCR-amplified 16S rRNA genes and 16S-23S rRNA gene intergenic spacers (ITS), repetitive element PCR (rep-PCR), arbitrarily primed PCR (AP-PCR) fingerprinting and random amplified polymorphic DNA (RAPD). Both of the 16S rRNA gene and 16S-23S rRNA gene intergenic spacers sequences of the three strains exhibited small variations, with 99.9-100%, 99.7-100% identity respectively. In contrast, according to the analysis of bacterial diversity based on rep-PCR and AP-PCR fingerprinting, they produced highly discriminatory banding patterns, and the similarity values between them varied from 61.97% to 71.64%. RAPD analysis showed that banding profiles of their genomic DNA exhibited obvious differences from each other with 53.44-75% similarity. These results suggested that in contrast to 16S rRNA genes and 16S-23S rRNA gene intergenic spacers sequencing analysis, rep-PCR, AP-PCR fingerprinting and RAPD analysis possessed higher discriminatory power in identifying these closely related strains. And they could be used as rapid and highly discriminatory typing techniques in studying bacterial diversity, especially in differentiating bacteria within Acidithiobacillus caldus.

scholarly journals Species-Specific PCR for Identification of Common Contaminant Mollicutes in Cell Culture

2001 ◽  
Vol 67 (7) ◽  
pp. 3195-3200 ◽  
Author(s):  
Fanrong Kong ◽  
Gregory James ◽  
Susanna Gordon ◽  
Anna Zelynski ◽  
Gwendolyn L. Gilbert
Keyword(s):  
16S Rrna ◽  
Cell Cultures ◽  
Bacterial Species ◽  
Intergenic Spacer ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Rrna Gene ◽  
Specific Pcr ◽  
Species Specific

ABSTRACT Mycoplasma arginini, M. fermentans, M. hyorhinis, M. orale, and Acholeplasma laidlawii are the members of the class Mollicutes most commonly found in contaminated cell cultures. Previous studies have shown that the published PCR primer pairs designed to detect mollicutes in cell cultures are not entirely specific. The 16S rRNA gene, the 16S-23S rRNA intergenic spacer region, and the 5′ end of the 23S rRNA gene, as a whole, are promising targets for design of mollicute species-specific primer pairs. We analyzed the 16S rRNA genes, the 16S-23S rRNA intergenic spacer regions, and the 5′ end of the 23S rRNA genes of these mollicutes and developed PCR methods for species identification based on these regions. Using high melting temperatures, we developed a rapid-cycle PCR for detection and identification of contaminant mollicutes. Previously published, putative mollicute-specific primers amplified DNA from 73 contaminated cell lines, but the presence of mollicutes was confirmed by species-specific PCR in only 60. Sequences of the remaining 13 amplicons were identified as those of gram-positive bacterial species. Species-specific PCR primers are needed to confirm the presence of mollicutes in specimens and for identification, if required.

scholarly journals Influence of Molecular Resolution on Sequence-Based Discovery of Ecological Diversity amongSynechococcusPopulations in an Alkaline Siliceous Hot Spring Microbial Mat

2010 ◽  
Vol 77 (4) ◽  
pp. 1359-1367 ◽  
Author(s):  
Melanie C. Melendrez ◽  
Rachel K. Lange ◽  
Frederick M. Cohan ◽  
David M. Ward
Keyword(s):  
16S Rrna ◽  
Internal Transcribed Spacer ◽  
Microbial Mats ◽  
Hot Spring ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Ecological Diversity ◽  
Protein Encoding ◽  
Internal Transcribed Spacer Sequences

ABSTRACTPrevious research has shown that sequences of 16S rRNA genes and 16S-23S rRNA internal transcribed spacer regions may not have enough genetic resolution to define all ecologically distinctSynechococcuspopulations (ecotypes) inhabiting alkaline, siliceous hot spring microbial mats. To achieve higher molecular resolution, we studied sequence variation in three protein-encoding loci sampled by PCR from 60°C and 65°C sites in the Mushroom Spring mat (Yellowstone National Park, WY). Sequences were analyzed using the ecotype simulation (ES) and AdaptML algorithms to identify putative ecotypes. Between 4 and 14 times more putative ecotypes were predicted from variation in protein-encoding locus sequences than from variation in 16S rRNA and 16S-23S rRNA internal transcribed spacer sequences. The number of putative ecotypes predicted depended on the number of sequences sampled and the molecular resolution of the locus. Chao estimates of diversity indicated that few rare ecotypes were missed. Many ecotypes hypothesized by sequence analyses were different in their habitat specificities, suggesting different adaptations to temperature or other parameters that vary along the flow channel.

Epibacterium ulvae gen. nov., sp. nov., epibiotic bacteria isolated from the surface of a marine alga

2013 ◽  
Vol 63 (Pt_5) ◽  
pp. 1589-1596 ◽  
Author(s):  
Anahit Penesyan ◽  
Sven Breider ◽  
Peter Schumann ◽  
Brian J. Tindall ◽  
Suhelen Egan ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Type Species ◽  
Marine Alga ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type

Two Gram-reaction-negative, rod-shaped, motile bacteria, designated strains U82 and U95T, were isolated from the marine alga Ulva australis collected at Sharks Point, Clovelly, a rocky intertidal zone near Sydney, Australia. Both strains were oxidase- and catalase-positive, formed brown- to black-pigmented colonies and required NaCl for growth. Phylogenetic analysis based on nearly complete 16S rRNA gene sequences revealed that these strains belong to the Roseobacter clade within the Alphaproteobacteria . The 16S rRNA genes of both strains were identical across the sequenced 1326 nt, but showed differences in the intergenic spacer region (ITS) between the 16S and the 23S rRNA genes. At the genomic level the DNA G+C contents of strains U82 and U95T were identical (52.6 mol%) and they had a DNA–DNA hybridization value of 83.7 %, suggesting that these strains belong to the same species. The closest described phylogenetic neighbour to strains U82 and U95T was Thalassobius aestuarii DSM 15283T with 95.8 % 16S rRNA gene sequence similarity. Other close relatives include further species of the genera Thalassobius and Shimia . Strains U82 and U95T were negative for bacteriochlorophyll a production, showed antibacterial activity towards other marine bacteria, were resistant to the antibiotics gentamicin and spectinomycin and were unable to hydrolyse starch or gelatin. The major fatty acids (>1 %) were 18 : 1ω7c, 16 : 0, 18 : 2, 10 : 0 3-OH, 12 : 0, 20 : 1 2-OH and 18 : 0. The polar lipid pattern indicated the presence of phosphatidylglycerol, phosphatidylcholine, two unidentified aminolipids and four unidentified phospholipids. Both strains produced ubiquinone 10 (Q-10) as the sole respiratory lipoquinone. Based on their phenotypic and phylogenetic characteristics, it is suggested that strains U82 and U95T are members of a novel species within a new genus for which the name Epibacterium ulvae gen. nov., sp. nov. is proposed. The type strain of the type species is U95T ( = DSM 24752T = LMG 26464T).

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