Further taxonomic characterization of the genus Bdellovibrio

Cultures of Bdellovibrio isolated from different geographic locations have been studied in terms of deoxyribonucleic acid analysis (% G + C, genome size, and DNA hybridization), cytochrome spectrum, and host range. Isolates of the genus exhibit a broad range of % G + C ranging from 37 to 51% and the genome sizes extend from 1300 × 106 to 1700 × 106 daltons. DNA hybridization continues to reveal a high level of genetic heterogeneity. Bdellovibrio 3294 exhibits 32% relative reassociation to Bdellovibrio W, 37% to Bdellovibrio stolpii Uki2, and an undetectible level to Bdellovibrio starrii A3.12. Bdellovibrio W is 23% related to B. starrii A3.12 and 28.5%to B. stolpii Uki2. For the first time differential absorption techniques have revealed peaks of cytochrome b. The analysis of the cytochrome spectrum seems to be limited as a taxonomic tool since most of the recent isolates studied share a common cytochrome spectrum. Host-range studies have been found to be dependent on the experimental conditions, and with the exception of one isolate (B. starrii A3.12) the taxonomic significance of such techniques must be taken with caution.

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Host Range of Streptomycete Strains Causing Common Scab

Plant Disease ◽

10.1094/pdis.1997.81.8.901 ◽

1997 ◽

Vol 81 (8) ◽

pp. 901-904 ◽

Cited By ~ 51

Author(s):

Claudia Goyer ◽

Carole Beaulieu

Keyword(s):

Host Range ◽

Daucus Carota ◽

Dna Hybridization ◽

Common Scab ◽

Genetic Cluster ◽

Dna Relatedness ◽

Physiological Characterization ◽

Genetic Clusters ◽

High Level

Ten Streptomyces isolates from common scab lesions on carrots (Daucus carota) were characterized. Morphological and physiological characterization of the carrot isolates established that they were closely related to S. scabies. DNA-DNA hybridization studies were carried out between DNA from the carrot isolates and DNA from two potato strains belonging to the two genetic clusters of S. scabies. Most of the carrot isolates exhibited a high level of DNA relatedness (average of 90%) to strain EF-54, which belongs to genetic cluster 1 of S. scabies. Three carrot isolates could not be included in either S. scabies genetic cluster 1 or 2. The pathogenicity of six S. scabies isolates from potato or carrot, two isolates of S. caviscabies, and one isolate of S. acidiscabies was determined on potato, carrot, radish, beet, turnip, and parsnip. All S. scabies isolates were pathogenic on carrot and radish, but pathogenicity on beet, parsnip, turnip, and potato was variable. Even though S. acidiscabies and S. caviscabies until now have been isolated only from potato, we demonstrated that isolates of these species also could infect other crops, such as radish, carrot, parsnip, and turnip.

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A Novel Genotype and First Record of Trypanosoma lainsoni in Argentina

Pathogens ◽

10.3390/pathogens9090731 ◽

2020 ◽

Vol 9 (9) ◽

pp. 731

Author(s):

Anahí G. Díaz ◽

Paula G. Ragone ◽

Fanny Rusman ◽

Noelia Floridia-Yapur ◽

Rubén M. Barquez ◽

...

Keyword(s):

Host Range ◽

First Record ◽

Morphological Characterization ◽

Pairwise Identity ◽

Wild Mammals ◽

Transmission Electron ◽

Chaco Region ◽

Veterinary Importance ◽

First Time

Trypanosomes are a group of parasitic flagellates with medical and veterinary importance. Despite many species having been described in this genus, little is known about many of them. Here, we report a genetic and morphological characterization of trypanosomatids isolated from wild mammals from the Argentine Chaco region. Parasites were morphologically and ultrastructurally characterized by light microscopy and transmission electron microscopy. Additionally, 18s rRNA and gGAPDH genes were sequenced and analyzed using maximum likelihood and Bayesian inference. Morphological characterization showed clear characteristics associated with the Trypanosoma genus. The genetic characterization demonstrates that the studied isolates have identical sequences and a pairwise identity of 99% with Trypanosoma lainsoni, which belongs to the clade of lizards and snakes/rodents and marsupials. To date, this species had only been found in the Amazon region. Our finding represents the second report of T. lainsoni and the first record for the Chaco region. Furthermore, we ultrastructurally described for the first time the species. Finally, the host range of T. lainsoni was expanded (Leopardus geoffroyi, Carenivora, Felidae; and Calomys sp., Rodentia, Cricetidae), showing a wide host range for this species.

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High Current Density Chronopotentiometric Electrosynthesis and SEM Characterization of Hexanethiol-Monolayer-Protected Silver Planar Nanotriangles (Ag@C6SH)

Journal of Nanomaterials ◽

10.1155/2016/5042670 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12

Author(s):

DJafar Vatan Khah Dowlat Sara ◽

Ahmad Rouhollahi ◽

Seied Mahdi Pourmortazavi ◽

Mojtaba Shamsipur

Keyword(s):

Current Density ◽

High Current Density ◽

Average Particle Size ◽

Average Particle ◽

Nonaqueous Media ◽

Experimental Conditions ◽

Vis Spectroscopy ◽

Optimized Conditions ◽

First Time

This work reports for the first time electrosynthesis of hexanethiol capped silver nanotriangles cores (Ag@C6SH NCs) by a rapid, clean, and simple Double Pulse Chronopotentiometric (DCP) method in nonaqueous media, using a Taguchi orthogonal arrayL8design to identify the optimized experimental conditions. It was found that the size and shape of the product could be tuned by the current density, electrolysis time, electrode distance, and amount of NaBH4% used. The Ag@C6SH NCs in different shapes and sizes (in the range of 30 to 44 nm as an average estimation) were synthesized, under different experimental conditions. Finally, the as-prepared nanoclusters electrosynthesized at optimized conditions were characterized by SEM, XRD, and UV-Vis spectroscopy. The average particle size of the triangular/pyramidal shape (Ag@C6SH NCs), obtained under optimized experimental conditions, was30.5±2.0 nm but the majority of nanoparticles in TC3SEM are so much finer.

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Psychroserpens mesophilus sp. nov., a mesophilic marine bacterium belonging to the family Flavobacteriaceae isolated from a young biofilm

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijs.0.64171-0 ◽

2006 ◽

Vol 56 (5) ◽

pp. 1055-1058 ◽

Cited By ~ 24

Author(s):

Kae Kyoung Kwon ◽

Soon Jae Lee ◽

Jae Hyun Park ◽

Tae-Young Ahn ◽

Hong Kum Lee

Keyword(s):

Marine Bacterium ◽

Methyl Esters ◽

Rrna Gene ◽

Respiratory Quinone ◽

The Family ◽

Major Respiratory Quinone ◽

Dominant Fatty Acid ◽

High Level ◽

Taxonomic Characterization

A number of marine bacteria isolated from young biofilms were characterized as belonging to the family Flavobacteriaceae. The taxonomic characterization of strain KOPRI 13649T, which was isolated from an acrylic surface at the seashore at Gangneung, Korea, is reported here. The nearly complete 16S rRNA gene sequence of strain KOPRI 13649T was determined and was found to have a high level of similarity with that of Psychroserpens burtonensis (95.0–95.6 %). In addition, phylogenetic analysis and comparison with closely related strains confirmed that the strain represented a novel member of the genus Psychroserpens. The major respiratory quinone of strain KOPRI 13649T was MK-6 and the DNA G+C content was 29.8 mol%. The dominant fatty acid methyl esters were i-15 : 0, a-15 : 0, i-16 : 0, i-15 : 1ω10, 16 : 1ω7 and 15 : 0. Growth was observed at 10–34 °C (optimum 30 °C), at pH 6–9 (optimum 6.5–8.0) and with 0.5–4 % NaCl (optimum 1 %). On the basis of the polyphasic taxonomic evidence presented, strain KOPRI 13649T (=KCCM 42261T=JCM 13413T) should be classified as the type strain of a novel species in the genus Psychroserpens, for which the name Psychroserpens mesophilus sp. nov. is proposed.

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Emergence of Proteus mirabilis HarboringblaKPC-2andqnrDin a Chinese Hospital

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05519-11 ◽

2012 ◽

Vol 56 (5) ◽

pp. 2278-2282 ◽

Cited By ~ 30

Author(s):

Yan-yan Hu ◽

Jia-chang Cai ◽

Rong Zhang ◽

Hong-wei Zhou ◽

Qian Sun ◽

...

Keyword(s):

Proteus Mirabilis ◽

Dna Hybridization ◽

Gel Electrophoresis ◽

Pulsed Field Gel Electrophoresis ◽

Quinolone Resistance ◽

Pfge Analysis ◽

Content Type ◽

High Level ◽

First Time ◽

Conjugation Experiment

ABSTRACTNineteen carbapenem-nonsusceptibleProteus mirabilisisolates were recovered from intensive care units in the Second Affiliated Hospital of Zhejiang University during a 3-month period. The isolates showed a high level of resistance against ciprofloxacin, in addition to their resistance against the carbapenems. Pulsed-field gel electrophoresis (PFGE) analysis showed that these isolates belonged to three clonal strains. PCRs and DNA sequence analysis of the carbapenemase and other β-lactamase genes indicated that all the isolates harbored theblaKPC-2gene. Twelve of 19 isolates harbored the plasmid-mediated quinolone resistance (PMQR) genes, both theqnrDandaac(6′)-Ib-crgenes. Eight representative isolates with high levels of quinolone resistance carried the similar mutation profiles of S83I ingyrA, E466D ingyrB, and S80I inparC. Reduced carbapenem susceptibility was transferred toEscherichia coli(EC600) in a conjugation experiment, while the quinolone resistance was not. DNA hybridization showed thatqnrDwas located on a plasmid of approximately 4.5 kb. In summary, large clonally related isolates of KPC-2-producingP. mirabilisemerged in a Chinese hospital, andqnrDwas detected in KPC-producingP. mirabilisfor the first time.

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Biochemical Changes in Nostoc linckia Associated with Selenium Nanoparticles Biosynthesis

Ecological Chemistry and Engineering S ◽

10.1515/eces-2016-0039 ◽

2016 ◽

Vol 23 (4) ◽

pp. 559-569 ◽

Cited By ~ 3

Author(s):

Inga Zinicovscaia ◽

Liudmila Rudi ◽

Ana Valuta ◽

Liliana Cepoi ◽

Konstantin Vergel ◽

...

Keyword(s):

Nanoparticle Synthesis ◽

Selenium Nanoparticles ◽

Experimental Conditions ◽

Biochemical Component ◽

Nostoc Linckia ◽

Component Content ◽

Amorphous Nanoparticles ◽

First Time ◽

Total Selenium

Abstract The cyanobacterium Nostoc linckia was used to study the biotechnology of selenium nanoparticles synthesis for the first time. The experimental conditions of the nanoparticle production by the studied cyanobacteria in aqueous cobalt selenite solutions were examined. Neutron activation analysis allowed characterization of the dynamics of accumulation of the total selenium quantity by Nostoc linckia. Scanning Electron Microscope images demonstrated extracellular formation of amorphous nanoparticles. Released selenium nanoparticles ranged in size from 10 to 80 nm. The changes of essential parameters of biomass (proteins, lipids, carbohydrates, and phycobilin) content during the nanoparticle formation were assessed. During the first 24 h of nanoparticle synthesis, a slight decline of proteins, lipids and carbohydrates content in the biomass was observed. The most extensive was the process of phycobilin degradation. Furthermore, all biochemical component content as well as an antioxidant activity of the biomass extracts significantly decreased. The obtained substance of Nostoc biomass with selenium nanoparticles may be used for medical, pharmaceutical and technological purposes.

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The nucleotide sequence homologies of unique DNA's of some cultivated and wild mushrooms

Canadian Journal of Microbiology ◽

10.1139/m84-088 ◽

1984 ◽

Vol 30 (5) ◽

pp. 587-593 ◽

Cited By ~ 15

Author(s):

Paul A. Horgen ◽

Richard Arthur ◽

Olia Davy ◽

Ann Moum ◽

Frank Herr ◽

...

Keyword(s):

Dna Hybridization ◽

Schizophyllum Commune ◽

Unique Sequence ◽

The Other ◽

Dna Duplexes ◽

Sequence Homologies ◽

Agaricus Bitorquis ◽

The Stability ◽

First Time

The unique sequence DNA's of several wild and cultivated fungi including Agaricus brunnescens (=Agaricus bisporus), Agaricus bitorquis, Amanita muscaria, Amanita phalloides, Pleurotus ostreatus, Lentinus edodes, and Schizophyllum commune were compared by DNA–DNA hybridization. In addition, the characterization of a number of fungal DNA's are reported for the first time. Unique sequence DNA from Agaricus brunnescens and P. ostreatus was labeled by nick translation and each was hybridized with an excess of unlabeled driver DNA. Unique sequence DNA from two different isolates of Agaricus brunnescens showed nearly complete homology with one another, while only 56% of the unique sequence DNA from Agaricus bitorquis hybridized with the same Agaricus brunnescens DNA. Furthermore, very little sequence homology existed between Agaricus brunnescens DNA and the DNA's of the other mushrooms studied. Similarly, very little hybridization occurred between P. ostreatus labeled DNA and the DNA's of the other species. The stability of the DNA duplexes was examined by thermal elution. The Tm of Agaricus brunnescens:Agaricus bitorquis duplexes was 7.7 °C lower than Agaricus brunnescens:Agaricus brunnescens duplexes. This indicated a 7.7–11.6% mismatch between the unique DNA's of these two species.

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Molecular characterization of trimethoprim resistance inShigella sonneiin Sicily

Epidemiology and Infection ◽

10.1017/s0950268800047610 ◽

1990 ◽

Vol 105 (1) ◽

pp. 29-40 ◽

Cited By ~ 8

Author(s):

A. Agodi ◽

C. Jones ◽

E. J. Threlfall ◽

M. D'Angelo ◽

M. Marranzano

Keyword(s):

Sri Lanka ◽

Dihydrofolate Reductase ◽

Plasmid Dna ◽

Dna Hybridization ◽

Plasmid Analysis ◽

V Gene ◽

Different Strains ◽

High Level ◽

Type V

SUMMARYDuring the 3-year period 1985–7, all strains ofShigella sonneiisolated in Catania, Sicily, showed a high level of resistance to trimethoprim (Tp) which was invariably associated with resistance to other antibiotics.Plasmid analysis showed 18 different electropherotypes: 35 of 37 strains harboured a plasmid of 70 Megadaltons (MDa), and 29 of 37 strains a plasmid of 130 MDa.Restriction endonuclease fingerprinting of purified 70 MDa plasmid DNA from different strains demonstrated that these plasmids were similar but not identical.In some strains with transferable Tp resistance, DNA hybridization analysis demonstrated the presence of genes coding for the production of dihydrofolate reductase (DHFR) type V. In contrast, there was no detectable hybridization with DNA probes specific for genes coding for DHFR types I, II and IV. This is the first report of the DHFR type V gene outside Sri Lanka.

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Taxonomic studies on species belonging to subgenus Eutricharaea Thomson of the genus Megachile (Hymenoptera: Megachilidae)

Journal of Applied and Natural Science ◽

10.31018/jans.v11i3.2125 ◽

2019 ◽

Vol 11 (3) ◽

pp. 612-618

Author(s):

Priyanka Kumari ◽

Neelima R. Kumar ◽

Avtar K. Sidhu ◽

Kailash Chandra

Keyword(s):

Large Scale ◽

Solitary Bee ◽

Northern Plains ◽

Spatio Temporal ◽

Taxonomic Studies ◽

First Time ◽

Taxonomic Characterization ◽

Different Parts ◽

Conservation Of Biodiversity

Solitary bees belonging to genus Megachile are important pollinators very crucial for the wellbeing of the ecosystem. Large scale surveying will return a wealth of spatio-temporal species data which is critical for systematics, taxonomy and conservation of biodiversity. Detailed taxonomic characterization of solitary bee species belonging to subgenus Eutricharaea collected from the Sutlej basin of Indian northern plains is being described. A total of four species viz. Megachile hera Bingham, M. femorata Smith, M. vera Cameron and M. argentata Cameron belonging to subgenus Eutricharaea with 18 examples were studied. Detailed morphological descriptions, zoogeographic records, specimen examined, floral associations with illustrations and morphological measurements have been provided. Various areas finalised from different parts of Sutlej basin of northern plains were surveyed for the first time for the documentation of Megachile fauna. Hence, all these four species are first records for the studied area.

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Screening and Morphological Characterization of Melons for Resistance to Fusarium oxysporum f.sp. melonis Race 1.2

HortScience ◽

10.21273/hortsci.45.7.1021 ◽

2010 ◽

Vol 45 (7) ◽

pp. 1021-1025 ◽

Cited By ~ 10

Author(s):

Hela Chikh-Rouhou ◽

Rafael González-Torres ◽

José María Alvarez ◽

Ali Oumouloud

Keyword(s):

Fusarium Oxysporum ◽

Partial Resistance ◽

Morphological Characteristics ◽

Morphological Characterization ◽

Sources Of Resistance ◽

Breeding Programs ◽

Commercial Cultivars ◽

High Level ◽

First Time

A total of 110 melon accessions with different geographical origins (18 countries) were screened for resistance to Fusarium oxysporum f.sp. melonis race 1.2 (pathotypes 1.2Y and 1.2W) using two artificial inoculation procedures. Twelve accessions showed some resistance to one or both strains. Three Japanese accessions, Shiro Uri Okayama (var. conomon), Kogane Nashi Makuwa, and C-211 (var. makuwa), and a Portuguese accession, BG-5384 (var. cantalupensis), showed the highest levels of resistance to both strains. The remaining eight accessions (all var. inodorus) had some level of partial resistance to 1.2W only. To our knowledge, this is the first time a high level of resistance to F. oxysporum f.sp. melonis race 1.2 has been identified in melon accessions of Western origin. The morphological traits of the 12 accessions that showed partial resistance were characterized to assess their suitability as resistance sources in melon breeding programs. Because most of the Western commercial cultivars belong to the cantalupensis, reticulatus, or inodorus botanical varieties, the resistant accessions from these varieties seem to be the most useful sources of resistance in breeding programs for developing melon cultivars of these types resistant to fusarium wilt race 1.2. The Portuguese accession BG-5384 had a high level of resistance within the Western types, and its morphological characteristics were fairly similar to some of the Western commercial cultivars.

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