Characterization of Streptomyces venezuelae ATCC 10595 rRNA gene clusters and cloning of rrnA.

The Amazon region contains a great diversity of species, and the Amazon River basin accounts for almost 20% of all the freshwater in the world. Despite the favorable environmental conditions in this region, little is known about the cyanobacterial diversity of this waterbody, especially at the mouth of the river. In this paper, we used the polyphasic approach to identify 14 cyanobacterial strains isolated in the Amazon River on the inlet site from a drinking water supply located close to the river mouth. The isolated strains were characterized based on morphology, behavior in culture, 16S rRNA gene sequencing, phylogenetic analysis and potential for toxin production. The isolated strains belong to seven different genera, namely, Alkalinema, Cephalothrix, Limnothrix, Leptolyngbya, Phormidium, Pseudanabaena and an unidentified Nostocales taxa that may represent a new genus. Strikingly, there were no new species, nor detection of gene clusters associated with cyanotoxin production. However, the phylogenetic placements of the Amazonian strains of Limnothrix and Pseudanabaena provide new insight into the taxonomy of these genera, reinforcing the need for taxonomic revision.

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Bioinformatics-assisted characterization of the ITS1-5·8S-ITS2 segments of nuclear rRNA gene clusters, and its exploitation in molecular diagnostics of European crop-parasitic nematodes of the genus Ditylenchus

Plant Pathology ◽

10.1111/j.1365-3059.2010.02322.x ◽

2010 ◽

Vol 59 (5) ◽

pp. 931-943 ◽

Cited By ~ 19

Author(s):

M. Marek ◽

M. Zouhar ◽

O. Douda ◽

J. Mazakova ◽

P. Rysanek

Keyword(s):

Molecular Diagnostics ◽

Gene Clusters ◽

Parasitic Nematodes ◽

Rrna Gene

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Characterization of the ribosomal RNA gene clusters in Halobacterium cutirubrum.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(20)71184-1 ◽

1985 ◽

Vol 260 (2) ◽

pp. 899-906

Author(s):

I Hui ◽

P P Dennis

Keyword(s):

Ribosomal Rna ◽

Gene Clusters ◽

Ribosomal Rna Gene

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Molecular characterization of a ceftriaxone-resistant Neisseria gonorrhoeae strain found in Switzerland: a case report

Annals of Clinical Microbiology and Antimicrobials ◽

10.1186/s12941-021-00456-5 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Konrad Egli ◽

Anna Roditscheff ◽

Ursula Flückiger ◽

Martin Risch ◽

Lorenz Risch ◽

...

Keyword(s):

Neisseria Gonorrhoeae ◽

23S Rrna ◽

Rrna Gene ◽

Limited Information ◽

Specific Pcr ◽

Appropriate Treatment ◽

23S Rrna Gene ◽

Allele Type ◽

Ciprofloxacin Resistance

Abstract Background The resistance of Neisseria gonorrhoeae to ceftriaxone is unusual in Switzerland. The underlying genotype responsible for resistance is suspected to be novel. Generally, resistance in Neisseria gonorrhoeae (Ng) involves a comprehensive set of genes with many different mutations leading to resistance to different β-lactams and fluoroquinolones. Case presentation A patient had a positive result from specific PCR for Ng. We routinely culture all clinical specimens with a positive NG-PCR. In this particular case, we isolated a strain with resistance to ceftriaxone in Switzerland. A total of seven different genes (penA, ponA, porinB, mtr, gyrA, parC, 23S rRNA gene) in this strain were partially sequenced for comparison with phenotypic susceptibility testing. Interestingly, two different mutations in the porinB gene were observed, and data on this gene are limited. Information on the identified allele type of the penA gene is very limited as well. Three different mutations of parC and gyrA that correlate with ciprofloxacin resistance were found. The combination of ceftriaxone and ciprofloxacin resistance makes an appropriate treatment difficult to obtain due to multidrug resistance. Conclusion The combined results for all genes show the appearance of new mutations in central Europe either due to worldwide spread or the emergence of new genetic combinations of mutations.

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Characterization of symbiotic and associated bacteria from entomopathogenic nematode Heterorhabditis sp. (nematode: Heterorhabditidae) isolated from India

Egyptian Journal of Biological Pest Control ◽

10.1186/s41938-020-00343-9 ◽

2020 ◽

Vol 30 (1) ◽

Author(s):

Rashid Pervez ◽

Showkat Ahmad Lone ◽

Sasmita Pattnaik

Keyword(s):

Insect Pests ◽

Entomopathogenic Nematode ◽

Alcaligenes Faecalis ◽

Symbiotic Bacteria ◽

Rrna Gene ◽

Main Body ◽

Associated Bacteria ◽

Molecular Approaches

Abstract Background Entomopathogenic nematodes (EPNs) harboring symbiotic bacteria are one of the safest alternatives to the chemical insecticides for the control of various insect pests. Infective juveniles of EPNs locate a target insect, enter through the openings, and reach the hemocoel, where they release the symbiotic bacteria and the target gets killed by the virulence factors of the bacteria. Photorhabdus with Heterorhabditis spp. are well documented; little is known about the associated bacteria. Main body In this study, we explored the presence of symbiotic and associated bacteria from Heterorhabditis sp. (IISR-EPN 09) and characterized by phenotypic, biochemical, and molecular approaches. Six bacterial isolates, belonging to four different genera, were recovered and identified as follows: Photorhabdus luminescens, one each strain of Providencia vermicola, Pseudomonas entomophila, Alcaligenes aquatilis, and two strains of Alcaligenes faecalis based on the phenotypic, biochemical criteria and the sequencing of 16S rRNA gene. Conclusion P. luminescens is symbiotically associated with Heterorhabditis sp. (IISR-EPN 09), whereas P. vermicola, P. entomophila, A. aquatilis, and A. faecalis are the associated bacteria. Further studies are needed to determine the exact role of the bacterial associates with the Heterorhabditis sp.

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Identification and Characterization of Inorganic Pyrophosphatase and PAP Phosphatase from Thermococcus onnurineus NA1

Journal of Bacteriology ◽

10.1128/jb.01699-08 ◽

2009 ◽

Vol 191 (10) ◽

pp. 3415-3419 ◽

Cited By ~ 4

Author(s):

Hyun Sook Lee ◽

Yun Jae Kim ◽

Jung-Hyun Lee ◽

Sung Gyun Kang

Keyword(s):

Gene Clusters ◽

Inorganic Pyrophosphatase ◽

Thermococcus Onnurineus Na1 ◽

First Report ◽

Activation System ◽

Sulfate Activation ◽

Pyrococcus Abyssi ◽

Identification And Characterization ◽

Hypothetical Genes

ABSTRACT Two hypothetical genes were functionally verified to be a pyrophosphatase and a PAP phosphatase in Thermococcus onnurineus NA1. This is the first report of the pyrophosphatases and the PAP phosphatases being organized in the gene clusters of the sulfate activation system only in T. onnurineus NA1 and “Pyrococcus abyssi.”

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Molecular characterization of the bacterial communities present in sheep's milk and cheese produced in South Brazilian Region via 16S rRNA gene metabarcoding sequencing

LWT ◽

10.1016/j.lwt.2021.111579 ◽

2021 ◽

Vol 147 ◽

pp. 111579

Author(s):

Creciana M. Endres ◽

Ícaro Maia S. Castro ◽

Laura D. Trevisol ◽

Juliana M. Severo ◽

Michele B. Mann ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Molecular Characterization ◽

Bacterial Communities ◽

Rrna Gene

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Nanopore-Sequencing Characterization of the Gut Microbiota of Melolontha melolontha Larvae: Contribution to Protection against Entomopathogenic Nematodes?

Pathogens ◽

10.3390/pathogens10040396 ◽

2021 ◽

Vol 10 (4) ◽

pp. 396

Author(s):

Ewa Sajnaga ◽

Marcin Skowronek ◽

Agnieszka Kalwasińska ◽

Waldemar Kazimierczak ◽

Karolina Ferenc ◽

...

Keyword(s):

Gut Microbiota ◽

Entomopathogenic Nematodes ◽

Bacterial Species ◽

Antagonistic Activity ◽

Rrna Gene ◽

Nanopore Sequencing ◽

Bacterial Phyla ◽

Melolontha Melolontha

This study focused on the potential relationships between midgut microbiota of the common cockchafer Melolontha melolontha larvae and their resistance to entomopathogenic nematodes (EPN) infection. We investigated the bacterial community associated with control and unsusceptible EPN-exposed insects through nanopore sequencing of the 16S rRNA gene. Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes were the most abundant bacterial phyla within the complex and variable midgut microbiota of the wild M. melolontha larvae. The core microbiota was found to include 82 genera, which accounted for 3.4% of the total number of identified genera. The EPN-resistant larvae differed significantly from the control ones in the abundance of many genera belonging to the Actinomycetales, Rhizobiales, and Clostridiales orders. Additionally, the analysis of the microbiome networks revealed different sets of keystone midgut bacterial genera between these two groups of insects, indicating differences in the mutual interactions between bacteria. Finally, we detected Xenorhabdus and Photorhabdus as gut residents and various bacterial species exhibiting antagonistic activity against these entomopathogens. This study paves the way to further research aimed at unravelling the role of the host gut microbiota on the output of EPN infection, which may contribute to enhancement of the efficiency of nematodes used in eco-friendly pest management.

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Characterization of the Aerobic Anoxygenic Phototrophic Bacterium Sphingomonas sp. AAP5

Microorganisms ◽

10.3390/microorganisms9040768 ◽

2021 ◽

Vol 9 (4) ◽

pp. 768

Author(s):

Karel Kopejtka ◽

Yonghui Zeng ◽

David Kaftan ◽

Vadim Selyanin ◽

Zdenko Gardian ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Sequence Similarity ◽

Orthologous Gene ◽

Gene Clusters ◽

Rrna Gene ◽

Unidentified Phospholipid ◽

Respiratory Quinone ◽

Polar Lipid Profile ◽

Close Phylogenetic Relationship

An aerobic, yellow-pigmented, bacteriochlorophyll a-producing strain, designated AAP5 (=DSM 111157=CCUG 74776), was isolated from the alpine lake Gossenköllesee located in the Tyrolean Alps, Austria. Here, we report its description and polyphasic characterization. Phylogenetic analysis of the 16S rRNA gene showed that strain AAP5 belongs to the bacterial genus Sphingomonas and has the highest pairwise 16S rRNA gene sequence similarity with Sphingomonas glacialis (98.3%), Sphingomonas psychrolutea (96.8%), and Sphingomonas melonis (96.5%). Its genomic DNA G + C content is 65.9%. Further, in silico DNA-DNA hybridization and calculation of the average nucleotide identity speaks for the close phylogenetic relationship of AAP5 and Sphingomonas glacialis. The high percentage (76.2%) of shared orthologous gene clusters between strain AAP5 and Sphingomonas paucimobilis NCTC 11030T, the type species of the genus, supports the classification of the two strains into the same genus. Strain AAP5 was found to contain C18:1ω7c (64.6%) as a predominant fatty acid (>10%) and the polar lipid profile contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, six unidentified glycolipids, one unidentified phospholipid, and two unidentified lipids. The main respiratory quinone was ubiquinone-10. Strain AAP5 is a facultative photoheterotroph containing type-2 photosynthetic reaction centers and, in addition, contains a xathorhodopsin gene. No CO2-fixation pathways were found.

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