scholarly journals Characterization of Diazotrophs Containing Mo-Independent Nitrogenases, Isolated from Diverse Natural Environments

2008 ◽  
Vol 74 (11) ◽  
pp. 3471-3480 ◽  
Author(s):  
Doris A. Betancourt ◽  
Telisa M. Loveless ◽  
James W. Brown ◽  
Paul E. Bishop
Keyword(s):  
Azotobacter Vinelandii ◽  
Wood Chip ◽  
Pcr Amplification ◽  
Rrna Gene ◽  
Natural Environments ◽  
Gene Sequence Analysis ◽  
Nitrogenase Genes ◽  
Free Media ◽  
Aerobic And Anaerobic

ABSTRACT Molybdenum-independent nitrogenases were first described in the nitrogen-fixing bacterium Azotobacter vinelandii and have since been described in other diazotrophic bacteria. Previously, we reported the isolation of seven diazotrophs with Mo-independent nitrogenases from aquatic environments. In the present study, we extend these results to include diazotrophs isolated from wood chip mulch, soil, “paraffin dirt,” and sediments from mangrove swamps. Mo-deficient, N-free media under both aerobic and anaerobic conditions were used for the isolations. A total of 26 isolates were genetically and physiologically characterized. Their phylogenetic placement was determined using 16S rRNA gene sequence analysis. Most of the isolates are members of the gamma subdivision of the class Proteobacteria and appear to be specifically related to fluorescent pseudomonads and azotobacteria. Two other isolates, AN1 and LPF4, are closely related to Enterobacter spp. and Paenibacillus spp., respectively. PCR and/or Southern hybridization were used to detect the presence of nitrogenase genes in the isolates. PCR amplification of vnfG and anfG was used to detect the genetic potential for the expression of the vanadium-containing nitrogenase and the iron-only nitrogenase in the isolates. This study demonstrates that diazotrophs with Mo-independent nitrogenases can be readily isolated from diverse natural environments.

scholarly journals Taxonomic characterization of nine strains isolated from clinical and environmental specimens, and proposal of Corynebacterium tuberculostearicum sp. nov.

2004 ◽  
Vol 54 (4) ◽  
pp. 1055-1061 ◽  
Author(s):  
Carole Feurer ◽  
Dominique Clermont ◽  
François Bimet ◽  
Adina Candréa ◽  
Mary Jackson ◽  
...  
Keyword(s):  
Gene Sequence ◽  
Fatty Acid Content ◽  
Food Samples ◽  
Cell Protein ◽  
Rrna Gene ◽  
Biochemical Tests ◽  
Taxonomic Analysis ◽  
Gene Sequence Analysis ◽  
Taxonomic Characterization

Nine unidentified Gram-positive, lipophilic corynebacteria were isolated from clinical and food samples and subjected to a polyphasic taxonomic analysis. The bacteria were distinguished from Corynebacterium species with validly published names by biochemical tests, fatty acid content and whole-cell protein analysis. Comparative 16S rRNA gene sequence analysis demonstrated unambiguously that the nine strains were related phylogenetically to the species ‘Corynebacterium tuberculostearicum’ and represented a distinct subline within the genus Corynebacterium. On the basis of both phenotypic and phylogenetic evidence, the formal description of Corynebacterium tuberculostearicum sp. nov. is proposed. The type strain of C. tuberculostearicum is Medalle XT (=LDC-20T=CIP 107291T=CCUG 45418T=ATCC 35529T).

IDENTIFICATION AND CHARACTERIZATION OF PIGMENTED BACTERIA ISOLATED FROM MALAYSIAN SEAWATER

2019 ◽  
Vol 7 (4) ◽  
pp. 01-08
Author(s):  
Nur Afifah Mursyida Zaujan ◽  
Mohamad Zohdi Othman ◽  
Fatin Najihah Mohd Lutfi ◽  
Kamarul Rahim Kamarudin ◽  
Hanina Mohd Noor ◽  
...  
Keyword(s):  
Human Health ◽  
Pcr Amplification ◽  
Fluorescent Light ◽  
Rrna Gene ◽  
Yellow Orange ◽  
Exiguobacterium Profundum ◽  
The Stability ◽  
Antimicrobial Metabolites ◽  
Pigmented Bacteria

Purpose of study: Bacteria can naturally produce pigments that can be useful for various applications as they possess antimicrobial metabolites among other numerous benefits towards the human health. This study was carried out to identify the species of marine bacterial isolates PMA, PM3C1 and PM5C1 exhibiting yellow, orange and green colors respectively. Methodology: The current study is using Polymerase Chain Reaction (PCR) amplification and sequence analysis of their 16S rRNA gene. The stability of pigments extracted from the bacterial samples was also analyzed against different temperature and light conditions. Main Findings: Sequence alignment using BLAST revealed that the yellow, orange, and green-pigmented bacteria have 84% similarity with Staphylococcus aureus, 85% similarity with Exiguobacterium profundum and 95% similarity with Pseudomonas aeruginosa respectively. The green pigment showed major changes in color following exposure to sunlight and fluorescent light, and when incubated at 24°C and 50°C. Exposure to direct sunlight also results in the reduction of color for the yellow and orange extracts, while no effect was observed for both pigments under fluorescent light. Incubation at 50°C results in the reduction of the orange color, while the yellow pigment was observed to be unaffected suggesting its stability at high temperature. Implications: Natural pigments production can provide many advantages including reduction of pollution generation, ease of disposal and other benefits to the human health.

Detection and Characterization of a Multi-drug and Multi-metal Resistant Enterobacterium Pantoea sp. from Tannery Wastewater after Secondary Treatment Process

2016 ◽  
Vol 2 (1 and 2) ◽  
pp. 37-42 ◽  
Author(s):  
Ashutosh Yadav ◽  
Abhay Raj ◽  
Ram Naresh Bharagava
Keyword(s):  
Toxic Metal ◽  
Tannery Wastewater ◽  
Contaminated Sites ◽  
Diffusion Method ◽  
Rrna Gene ◽  
Disk Diffusion Method ◽  
Gene Sequence Analysis ◽  
Nutrient Agar Medium ◽  
The 16S Rrna Gene

In this study, an enterobacterium was isolated from treated tannery wastewater and characterized as gram-negative, rod shaped, motile, and lactose fermenting bacterium. Further, based on the 16S rRNA gene sequence analysis, the bacterium was identified as Pantoea sp. with accession number The antibiotic and heavy KJ576899. metal resistant property of isolated bacterium was investigated by the disk diffusion method on Muller-Hinton and nutrient agar medium amended with the increasing concentrations of various toxic metal ions, respectively. Results showed that the isolated bacterium was sensitive for amikacin, ampicillin, cefepime, cetriaxone, chloramphenicol, levofloxacin, meropenem, nalidixic acid, piperacillin and tobramycin, resistant for aztreonam, carbenicillin, cefotaxime, ceftazidime, ciprofloxacin, cotrimoxazole, imepenam, moxifloxacin, streptomycin and tetracycline, but intermediate for amoxicillin and gentamicin. In addition, the bacterium also showed the Minimum Inhibitory Concentration (MIC) values of 250, 500, 160, 190, 600, 700, 500, 380, 600 and 350 μg ml-1 forCu, Cr, Cd, Co, Zn, Fe, Ni, Pb, Mo and As, respectively with a plasmid DNA of 33.5 kb. This multi-drug and multi-metal resistant bacterium can be used as a potential agent for the bioremediation of metal contaminated sites.

scholarly journals Geobacillus lituanicus sp. nov.

2004 ◽  
Vol 54 (6) ◽  
pp. 1991-1995 ◽  
Author(s):  
Nomeda Kuisiene ◽  
Juozas Raugalas ◽  
Donaldas Chitavichius
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Novel Species ◽  
Sequence Similarity ◽  
Rrna Gene ◽  
The Novel ◽  
Gene Sequence Analysis ◽  
Pcr Rflp ◽  
Group 5

Obligately thermophilic, aerobic, proteolytic, endospore-forming strain N-3T was isolated from a high-temperature oilfield in Lithuania. 16S rRNA gene sequence analysis placed this strain in genetic group 5 of the endospore formers. Geobacillus thermoleovorans appeared to be the closest phylogenetic neighbour (99·4 % sequence similarity). The G+C content of strain N-3T was 52·5 mol% and matched the range established for the genus Geobacillus. Studies of DNA–DNA relatedness and morphological and physiological analyses enabled strain N-3T to be described as a member of the genus Geobacillus, but could not assign this strain to any other known species of this genus. Results of this polyphasic study allowed characterization of strain N-3T as a novel species in the genus Geobacillus – Geobacillus lituanicus sp. nov. This species can be distinguished from G. thermoleovorans and Geobacillus stearothermophilus on the basis of 16S rRNA gene PCR-RFLP assays with the restriction endonucleases AluI, HaeIII and TaqI. The type strain of the novel species is N-3T (=DSM 15325T=VKM B-2294T).

scholarly journals Genetic characterization of Blastocystis from wild animals in Sichuan Wolong National Natural Reserve, southwestern of China-Zoonotic potential

2021 ◽  
Author(s):  
Shanyu Chen ◽  
Wangyu Meng ◽  
Ziyao Zhou ◽  
Lei Deng ◽  
Xiaogang Shi ◽  
...  
Keyword(s):  
Pcr Amplification ◽  
Human Infection ◽  
Rrna Gene ◽  
Zoonotic Potential ◽  
Wild Animals ◽  
Genetic Characteristics ◽  
Natural Reserve ◽  
Faecal Samples ◽  
Wide Range

Abstract Background Blastocystis, a highly prevalent eukaryotic parasite, has been identified in a wide range of hosts, including humans, domestic and wild animals. Many animals are potential sources of Blastocystis infection for humans, while few information about the prevalence of Blastocystis in wild animals have being documented. Therefore, the present study was designed to investigate the prevalence and subtypes of Blastocystis in wild animals of Sichuan Wolong National Natural Reserve, southwestern of China, so as to assess the zoonotic potential of these animals. Methods A total of 300 faecal samples were collected from 27 wildlife species in three areas of Sichuan Wolong National Natural Reserve in southwestern China. The subtype (ST) genetic characteristics and prevalence of Blastocystis were determined by PCR amplification of the barcode region (a fragment of ∼600 bp) of the SSU rRNA gene, and phylogenetic analysis were further performed to determine the genetic characteristics of Blastocystis subtypes. Results 30 of 300 faecal samples (10.0%) were Blastocystis-positive. The highest prevalence of Blastocystis was found in Yinchanggou (18.3%), which was significantly higher than that in Niutoushan (7.5%), and Genda (5.5%) (P < 0.05). Specifically, the highest prevalence of Blastocystis was found in primates (20.0%, 1/5), followed by rodentia 14.3% (1/7), artiodactyla 13.1% (26/198), carnivora 2.3% (2/87), galliformes 0% (0/3). Sequence analysis showed 5 subtypes (ST1, ST3, ST5, ST13, and ST14), with ST13 and ST14 as the predominant subtype (33.3%, 10/30), followed by ST1 (20.0%, 6/30). Conclusions To the best of our knowledge, this is the first molecular investigation on Blastocystis infection in wild animals in southwestern of China. ST1, ST3, and ST5 were identified in both humans and wild animals, suggesting that these wild animals may be potential reservoirs of Blastocystis for human infection.

scholarly journals Identification and molecular characterization of Wolbachia strains in natural populations of Aedes albopictus in China

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Yaping Hu ◽  
Zhiyong Xi ◽  
Xiaobo Liu ◽  
Jun Wang ◽  
Yuhong Guo ◽  
...  
Keyword(s):  
Aedes Albopictus ◽  
Dengue Infection ◽  
Natural Populations ◽  
Pcr Amplification ◽  
Surface Protein ◽  
Multiple Infection ◽  
Rrna Gene ◽  
Dengue Outbreaks ◽  
Surface Protein Gene

Abstract Background Aedes albopictus is naturally infected with Wolbachia spp., maternally transmitted bacteria that influence the reproduction of hosts. However, little is known regarding the prevalence of infection, multiple infection status, and the relationship between Wolbachia density and dengue outbreaks in different regions. Here, we assessed Wolbachia infection in natural populations of Ae. albopictus in China and compared Wolbachia density between regions with similar climates, without dengue and with either imported or local dengue. Results To explore the prevalence of Wolbachia infection, Wolbachia DNA was detected in mosquito samples via PCR amplification of the 16S rRNA gene and the surface protein gene wsp. We found that 93.36% of Ae. albopictus in China were positive for Wolbachia. After sequencing gatB, coxA, hcpA, ftsZ, fbpA and wsp genes of Wolbachia strains, we identified a new sequence type (ST) of wAlbB (464/465). Phylogenetic analysis indicated that wAlbA and wAlbB strains formed a cluster with strains from other mosquitoes in a wsp-based maximum likelihood (ML) tree. However, in a ML tree based on multilocus sequence typing (MLST), wAlbB STs (464/465) did not form a cluster with Wolbachia strains from other mosquitoes. To better understand the association between Wolbachia spp. and dengue infection, the prevalence of Wolbachia in Ae. albopictus from different regions (containing local dengue cases, imported dengue cases and no dengue cases) was determined. We found that the prevalence of Wolbachia was lower in regions with only imported dengue cases. Conclusions The natural prevalence of Wolbachia infections in China was much lower than in other countries or regions. The phylogenetic relationships among Wolbachia spp. isolated from field-collected Ae. albopictus reflected the presence of dominant and stable strains. However, wAlbB (464/465) and Wolbachia strains did not form a clade with Wolbachia strains from other mosquitoes. Moreover, lower densities of Wolbachia in regions with only imported dengue cases suggest a relationship between fluctuations in Wolbachia density in field-collected Ae. albopictus and the potential for dengue invasion into these regions.

scholarly journals Prevalence and Genetic Characterization of Cryptosporidium Infection in Java Sparrows (Lonchura oryzivora) in Northern China

2017 ◽  
Vol 2017 ◽  
pp. 1-4 ◽  
Author(s):  
Qiu-Xia Yao ◽  
Xiao-Xuan Zhang ◽  
Kai Chen ◽  
Jian-Gang Ma ◽  
Wen-Bin Zheng ◽  
...  
Keyword(s):  
Pcr Amplification ◽  
Northern China ◽  
Small Subunit ◽  
Rrna Gene ◽  
Ssu Rrna ◽  
Ssu Rrna Gene ◽  
Wide Range ◽  
Baseline Information ◽  
And Control

Cryptosporidiosis is a cosmopolitan parasitosis that affects a wide range of hosts including birds. As information concerning Cryptosporidium in birds is limited, the present study examined the prevalence and genotypes of Cryptosporidium in Java sparrows in Beijing and Shangqiu, northern China. Three hundred and fifty fecal samples were collected from Java sparrows (Lonchura oryzivora, 225 white Java sparrows and 125 gray Java sparrows) in Beijing and Shangqiu in October 2015, and the samples were examined by PCR amplification of the small subunit ribosomal RNA (SSU rRNA) gene. The overall Cryptosporidium prevalence is 13.42% (47/350), with 16.44% (37/225) in white Java sparrows and 8.00% (10/125) in gray Java sparrows. Cryptosporidium prevalence was 9.82% (16/163) in Java sparrows from Beijing and 16.58% (31/187) in Java sparrows from Shangqiu. The prevalence of Cryptosporidium in females and males was 40.63% (26/64) and 7.34% (21/286), respectively. The Cryptosporidium prevalence in Java sparrows of different ages varied from 10.47% to 16.33%. Sequence analysis of the SSU rRNA gene revealed that all the samples represented C. baileyi. This is the first report of Cryptosporidium in gray Java sparrows in China, which extend the host range for C. baileyi. These results provide baseline information for further studies of molecular epidemiology and control of Cryptosporidium infection in poultry in China.

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