Molecular identification of pufferfish species using PCR amplification and restriction analysis of a segment of the 16S rRNA gene

Author(s):  
Shoichiro Ishizaki ◽  
Yasuhiro Yokoyama ◽  
Naomasa Oshiro ◽  
Natsuko Teruya ◽  
Yuji Nagashima ◽  
...  
2002 ◽  
Vol 68 (8) ◽  
pp. 4130-4131 ◽  
Author(s):  
John E. Moore ◽  
Mark McCalmont ◽  
Jiru Xu ◽  
B. Cherie Millar ◽  
Neville Heaney

ABSTRACT A gram-negative bacillus was isolated from a batch of fruit-flavored bottled water, which had spoiled as a result of bacterial overgrowth (>106 CFU/ml). The spoilage organism was extremely difficult to identify phenotypically and was poorly identified as Pasturella sp. (78.7% identification profile) employing the API 20NE identification scheme, which gave the profile 5040000. Molecular identification through PCR amplification of a partial region of the 16S rRNA gene followed by direct automated sequencing of the PCR amplicon allowed identification of the organism. Due to the sequence identity (100%) between the spoilage organism and a reference strain in GenBank, the spoilage isolate was considered to be an Asaia sp., a recently described genus and member of the acetic acid bacteria. This is the first report of Asaia sp. causing spoilage of a foodstuff and highlights the benefits of molecular identification techniques based on 16S rRNA gene sequences in the identification of unusual spoilage organisms.


2002 ◽  
Vol 68 (8) ◽  
pp. 3818-3829 ◽  
Author(s):  
Christopher Rösch ◽  
Alexander Mergel ◽  
Hermann Bothe

ABSTRACT Isolated soil DNA from an oak-hornbeam forest close to Cologne, Germany, was suitable for PCR amplification of gene segments coding for the 16S rRNA and nitrogenase reductase (NifH), nitrous oxide reductase (NosZ), cytochrome cd 1-containing nitrite reductase (NirS), and Cu-containing nitrite reductase (NirK) of denitrification. For each gene segment, diverse PCR products were characterized by cloning and sequencing. None of the 16S rRNA gene sequences was identical to any deposited in the data banks, and therefore each of them belonged to a noncharacterized bacterium. In contrast, the analyzed clones of nifH gave only a few different sequences, which occurred many times, indicating a low level of species richness in the N2-fixing bacterial population in this soil. Identical nifH sequences were also detected in PCR amplification products of DNA of a soil approximately 600 km distant from the Cologne area. Whereas biodiversity was high in the case of nosZ, only a few different sequences were obtained with nirK. With respect to nirS, cloning and sequencing of the PCR products revealed that many false gene segments had been amplified with DNA from soil but not from cultured bacteria. With the 16S rRNA gene data, many sequences of uncultured bacteria belonging to the Acidobacterium phylum and actinomycetes showed up in the PCR products when isolated DNA was used as the template, whereas sequences obtained for nifH and for the denitrification genes were closely related to those of the proteobacteria. Although in such an experimental approach one has to cope with the enormous biodiversity in soils and only a few PCR products can be selected at random, the data suggest that denitrification and N2 fixation are not genetic traits of most of the uncultured bacteria.


2007 ◽  
Vol 45 (4) ◽  
pp. 1376-1377 ◽  
Author(s):  
A. D. Raut ◽  
B. P. Kapadnis ◽  
R. Shashidhar ◽  
J. R. Bandekar ◽  
P. Vaishampayan ◽  
...  

2020 ◽  
Vol 13 (1) ◽  
pp. 10-18
Author(s):  
Mochamad Untung Kurnia - Agung ◽  
Agus Tri Askar ◽  
Yuli Andriani ◽  
Lintang Permatasari Yuliadi

Contamination of coliform bacteria in benthic foraminifera has been reported due to pollution of organic wastes in the aquatic environment around coral reef ecosystems and this event was known to interfere the process of foraminifera shell formation which in turn resulted the disruption of the role of foraminifera in the process of formation of coral reef bottom sediments. The aim of this research is to identify the isolates of culturable coliform bacteria that contaminate foraminifera Calcarina species isolated from the waters of the Pramuka Island, the Seribu Island district, Jakarta Province using the 16S rRNA gene markers. Foraminifera sampling was carried out in the waters of Pramuka Island, the Seribu Island district, Jakarta Province in 5 (five) stations, while the process of bacterial isolation and molecular identification were carried out at the Laboratory of Microbiology and Molecular Biotechnology (MICROMOL), Faculty of Fisheries and Marine Sciences (FPIK), University Padjadjaran. Molecular identification was carried out using the Polymerase Chain Reaction (PCR) method based on the 16S rRNA gene markers. Sequencing is done by sending PCR results to 1st Base, sequencing service company, in Singapore and then, the aligning of sequencing results with databases in genBank was done using  the Basic Local Alignment Search Tool (BLASTTM) program available on the National Center for Biotechnology Information (NCBI) website. The results of 16S rRNA gene amplification from the five isolates produced amplicons of ± 1400 bp length with concentrations ranging from 157.5 µg / mL-230 µg / mL and with a purity ratio ranging from 1.477-1.769. While the results of BLAST and phylogenetic analysis showed that the five isolates were closely related to the isolate Eschericia coli strain inspire99 (Acc No. JQ315935.1), which was isolated from the waters of the Bay of Bengal, India. These results also indicate the existence of ecological connectivity between the waters of the Bay of Bengal in India and the waters of Pramuka Island in Indonesia.


2005 ◽  
Vol 55 (5) ◽  
pp. 1857-1862 ◽  
Author(s):  
Diva do Carmo Teixeira ◽  
Colette Saillard ◽  
Sandrine Eveillard ◽  
Jean Luc Danet ◽  
Paulo Inácio da Costa ◽  
...  

Symptoms of huanglongbing (HLB) were reported in São Paulo State (SPS), Brazil, in March 2004. In Asia, HLB is caused by ‘Candidatus Liberibacter asiaticus' and in Africa by ‘Candidatus Liberibacter africanus’. Detection of the liberibacters is based on PCR amplification of their 16S rRNA gene with specific primers. Leaves with blotchy mottle symptoms characteristic of HLB were sampled in several farms of SPS and tested for the presence of liberibacters. ‘Ca. L. asiaticus' was detected in a small number of samples but most samples gave negative PCR results. Therefore, a new HLB pathogen was suspected. Evidence for an SPS-HLB bacterium in symptomatic leaves was obtained by PCR amplification with universal primers for prokaryotic 16S rRNA gene sequences. The amplified 16S rRNA gene was cloned and sequenced. Sequence analysis and phylogeny studies showed that the 16S rRNA gene possessed the oligonucleotide signatures and the secondary loop structure characteristic of the α-Proteobacteria, including the liberibacters. The 16S rRNA gene sequence phylogenetic tree showed that the SPS-HLB bacterium clustered within the α-Proteobacteria, the liberibacters being its closest relatives. For these reasons, the SPS-HLB bacterium is considered a member of the genus ‘Ca. Liberibacter’. However, while the 16S rRNA gene sequences of ‘Ca. L. asiaticus' and ‘Ca. L. africanus' had 98·4 % similarity, the 16S rRNA gene sequence of the SPS-HLB liberibacter had only 96·0 % similarity with the 16S rRNA gene sequences of ‘Ca. L. asiaticus' or ‘Ca. L. africanus’. This lower similarity was reflected in the phylogenetic tree, where the SPS-HLB liberibacter did not cluster within the ‘Ca. L asiaticus’/‘Ca. L. africanus group’, but as a separate branch. Within the genus ‘Candidatus Liberibacter’ and for a given species, the 16S/23S intergenic region does not vary greatly. The intergenic regions of three strains of ‘Ca. L. asiaticus’, from India, the People's Republic of China and Japan, were found to have identical or almost identical sequences. In contrast, the intergenic regions of the SPS-HLB liberibacter, ‘Ca. L. asiaticus' and ‘Ca. L. africanus' had quite different sequences, with similarity between 66·0 and 79·5 %. These results confirm that the SPS-HLB liberibacter is a novel species for which the name ‘Candidatus Liberibacter americanus' is proposed. Like the African and the Asian liberibacters, the ‘American’ liberibacter is restricted to the sieve tubes of the citrus host. The liberibacter could also be detected by PCR amplification of the 16S rRNA gene in Diaphorina citri, the psyllid vector of ‘Ca. L. asiaticus’, suggesting that this psyllid is also a vector of ‘Ca. L. americanus' in SPS. ‘Ca. L. americanus' was detected in 216 of 218 symptomatic leaf samples from 47 farms in 35 municipalities, while ‘Ca. L. asiaticus' was detected in only 4 of the 218 samples, indicating that ‘Ca. L. americanus' is the major cause of HLB in SPS.


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