scholarly journals Isolation and molecular identification of Acanthamoeba spp. from hot springs in Mazandaran province, northern Iran

2018 ◽  
Vol 16 (5) ◽  
pp. 807-813 ◽  
Author(s):  
Samira Dodangeh ◽  
Elham Kialashaki ◽  
Ahmad Daryani ◽  
Mehdi Sharif ◽  
Shahabeddin Sarvi ◽  
...  

Abstract Acanthamoeba is a free-living protozoan that can be found in natural and artificial environments such as hot tubs, surface water and springs and can cause severe diseases including amoebic keratitis and granulomatous amoebic encephalitis. The present study was conducted owing to the lack of research regarding genotypes of Acanthamoeba in hot springs of Mazandaran province in northern Iran. Twenty-four water samples were collected from all hot springs in Mazandaran province. After filtration through nitrocellulose membrane, samples were cultured on non-nutrient agar medium enriched with TYIS-33. The cultures were microscopically examined for the presence of Acanthamoeba. Positive cultures were analysed by polymerase chain reaction (PCR) and genotypes were determined by targeting the 18 S rRNA gene. The pathogenic potential of all positive isolates was identified using thermotolerance and osmotolerance tests. Eleven (47.8%) samples were positive for Acanthamoeba. Based on sequencing analysis, 100% of isolates belonged to the T4 genotype. Thermo- and osmo-tolerance tests showed that four (36.3%) Acanthamoeba strains were highly pathogenic. According to our research, the occurrence of Acanthamoeba in recreational hot springs could be a hazard for high risk persons. Posting warning signs and regular monitoring of these waters by health planners may therefore be useful for decreasing Acanthamoeba spp. infections.

2016 ◽  
Vol 144 (11) ◽  
pp. 2456-2461 ◽  
Author(s):  
A. R. LATIFI ◽  
M. NIYYATI ◽  
J. LORENZO-MORALES ◽  
A. HAGHIGHI ◽  
S. J. SEYYED TABAEI ◽  
...  

SUMMARYBalamuthia mandrillaris is an opportunistic free-living amoeba that has been reported to cause cutaneous lesions and Balamuthia amoebic encephalitis. The biology and environmental distribution of B. mandrillaris is still poorly understood and isolation of this pathogen from the environment is a rare event. Previous studies have reported that the presence of B. mandrillaris in the environment in Iran may be common. However, no clinical cases have been reported so far in this country. In the present study, a survey was conducted in order to evaluate the presence of B. mandrillaris in hot-spring samples of northern Iran. A total of 66 water samples were analysed using morphological and molecular tools. Positive samples by microscopy were confirmed by performing PCR amplification of the 16S rRNA gene of B. mandrillaris. Sequencing of the positive amplicons was also performed to confirm morphological data. Two of the 66 collected water samples were positive for B. mandrillaris after morphological and molecular identification. Interestingly, both positive hot springs had low pH values and temperatures ranging from 32 °C to 42 °C. Many locals and tourists use both hot springs due to their medicinal properties and thus contact with water bodies containing the organism increases the likelihood of infection. To the best of our knowledge, this is the first report on the isolation of B. mandrillaris from hot-spring sources related to human activity. Therefore, B. mandrillaris should be considered as a possible causative agent if cases of encephalitis are suspected following immersion in hot springs in addition to Acanthamoeba and Naegleria.


2015 ◽  
Vol 8s1 ◽  
pp. MBI.S24099 ◽  
Author(s):  
Maryam Niyyati ◽  
Zohreh Lasgerdi ◽  
Jacob Lorenzo-Morales

Amoebic keratitis, a sight-threatening corneal infection, mainly occurs in contact lens wearers who wash their eyes with tap water. The present research was conducted to identify the occurrence of potentially pathogenic free-living amoebae (FLA) in tap water sources on Kish Island, a tourist region in Iran. Amoebae were detected using a culture-enriched method and by polymerase chain reaction (PCR)/sequencing of the diagnostic fragment 3 region of the 18S rRNA gene of Acanthamoeba. In the case of other free-living amoebae species, PCR/sequencing analysis of the 18S rDNA was conducted. Results of this study showed the presence of Acanthamoeba belonging to T3, T4, T5, and T11 genotypes in tap water sources. Additionally, Vermamoebae vermiformis was detected in three water samples. This is the first report of the Acanthamoeba genotypes T3, T4, T5, and T11 and V. vermiformis species in tap water sources in a tourist region in Iran.


2019 ◽  
Vol 17 (5) ◽  
pp. 813-825 ◽  
Author(s):  
Rosnani Hanim Mohd Hussain ◽  
Ahmad Razali Ishak ◽  
Mohamed Kamel Abdul Ghani ◽  
Naveed Ahmed Khan ◽  
Ruqaiyyah Siddiqui ◽  
...  

Abstract This study aimed to identify the Acanthamoeba genotypes and their pathogenic potential in five recreational hot springs in Peninsular Malaysia. Fifty water samples were collected between April and September 2018. Physical parameters of water quality were measured in situ while chemical and microbiological analyses were performed in the laboratory. All samples were filtered through the nitrocellulose membrane and tested for Acanthamoeba using both cultivation and polymerase chain reaction (PCR) by targeting the 18S ribosomal RNA gene. The pathogenic potential of all positive isolates was identified using thermo- and osmotolerance tests. Thirty-eight (76.0%) samples were positive for Acanthamoeba. Water temperature (P = 0.035), chemical oxygen demand (P = 0.026), sulphate (P = 0.002) and Escherichia coli (P < 0.001) were found to be significantly correlated with the presence of Acanthamoeba. Phylogenetic analysis revealed that 24 samples belonged to genotype T4, nine (T15), two (T3) and one from each genotype T5, T11 and T17. Thermo- and osmotolerance tests showed that 6 (15.79%) of the Acanthamoeba strains were highly pathogenic. The existence of Acanthamoeba in recreational hot springs should be considered as a health threat among the public especially for high-risk people. Periodic surveillance of hot spring waters and posting warning signs by health authorities is recommended to prevent disease related to pathogenic Acanthamoeba.


Author(s):  
Asal Tanzifi ◽  
Yousef Moghaddam ◽  
Samira Dodangeh ◽  
Ahmad Daryani ◽  
Shahabeddin Sarvi ◽  
...  

Background: Free-living amoeba (FLA) belonging to Acanthamoeba spp., Naegleria, and Balamuthia mandrillaris are the soil-born protozoa. This study aimed to survey the occurrence of FLA, including Acanthamoeba spp., B. mandrillaris, Vermamoeba spp., and Naegleria spp., in soil samples collected from various districts of Mazandaran Province (Northern Iran) from July to December 2018. Methods: Overall, 118 soil samples from the recreational and public places were surveyed for the existence of Acanthamoeba spp., Vermamoeba, Naegleria, and B. mandrillaris using both morphological key and molecular tools with genus-specific primers of JDP1, NA, ITS1, and Bal, respectively. To verify the taxonomic status of isolated amoeba, the phylogenetic tree was made based on sequences of 18S rRNA by MEGA (5.05) software with the maximum likelihood model. Results: Overall, 61/118 samples (51.6%) were contaminated with FLA, and based on the sequencing data, 29 isolates were successfully sequenced. Among the samples, all isolated Acanthamoeba (52.4%) belonged to the T4 genotype with amplification of the DF3 region (18S rRNA gene). Internal transcribed spacer (ITS) sequencing revealed the presence of one strain of Naegleria americana. Twenty-eight V. vermiformis were also confirmed based on Nuclear SSU rDNA. Morphological survey and PCR assay did not show any positive samples for B. mandrillaris. Conclusion: The present study indicates the occurrence of FLA in soil sources of the recreational and public places in Mazandaran province that it can be a severe risk to human health. Thus, more studies are expected to survey the infection source in patients with FLA-related diseases.


2021 ◽  
Vol 9 (6) ◽  
pp. 1307
Author(s):  
Sebastian Böttger ◽  
Silke Zechel-Gran ◽  
Daniel Schmermund ◽  
Philipp Streckbein ◽  
Jan-Falco Wilbrand ◽  
...  

Severe odontogenic abscesses are regularly caused by bacteria of the physiological oral microbiome. However, the culture of these bacteria is often prone to errors and sometimes does not result in any bacterial growth. Furthermore, various authors found completely different bacterial spectra in odontogenic abscesses. Experimental 16S rRNA gene next-generation sequencing analysis was used to identify the microbiome of the saliva and the pus in patients with a severe odontogenic infection. The microbiome of the saliva and the pus was determined for 50 patients with a severe odontogenic abscess. Perimandibular and submandibular abscesses were the most commonly observed diseases at 15 (30%) patients each. Polymicrobial infections were observed in 48 (96%) cases, while the picture of a mono-infection only occurred twice (4%). On average, 31.44 (±12.09) bacterial genera were detected in the pus and 41.32 (±9.00) in the saliva. In most cases, a predominantly anaerobic bacterial spectrum was found in the pus, while saliva showed a similar oral microbiome to healthy individuals. In the majority of cases, odontogenic infections are polymicrobial. Our results indicate that these are mainly caused by anaerobic bacterial strains and that aerobic and facultative anaerobe bacteria seem to play a more minor role than previously described by other authors. The 16S rRNA gene analysis detects significantly more bacteria than conventional methods and molecular methods should therefore become a part of routine diagnostics in medical microbiology.


2021 ◽  
Vol 9 (7) ◽  
pp. 1473
Author(s):  
Ani Saghatelyan ◽  
Armine Margaryan ◽  
Hovik Panosyan ◽  
Nils-Kåre Birkeland

The microbial diversity of high-altitude geothermal springs has been recently assessed to explore their biotechnological potential. However, little is known regarding the microbiota of similar ecosystems located on the Armenian Highland. This review summarizes the known information on the microbiota of nine high-altitude mineralized geothermal springs (temperature range 25.8–70 °C and pH range 6.0–7.5) in Armenia and Nagorno-Karabakh. All these geothermal springs are at altitudes ranging from 960–2090 m above sea level and are located on the Alpide (Alpine–Himalayan) orogenic belt, a seismically active region. A mixed-cation mixed-anion composition, with total mineralization of 0.5 mg/L, has been identified for these thermal springs. The taxonomic diversity of hot spring microbiomes has been examined using culture-independent approaches, including denaturing gradient gel electrophoresis (DGGE), 16S rRNA gene library construction, 454 pyrosequencing, and Illumina HiSeq. The bacterial phyla Proteobacteria, Bacteroidetes, Cyanobacteria, and Firmicutes are the predominant life forms in the studied springs. Archaea mainly include the phyla Euryarchaeota, Crenarchaeota, and Thaumarchaeota, and comprise less than 1% of the prokaryotic community. Comparison of microbial diversity in springs from Karvachar with that described for other terrestrial hot springs revealed that Proteobacteria, Bacteroidetes, Actinobacteria, and Deinococcus–Thermus are the common bacterial groups in terrestrial hot springs. Contemporaneously, specific bacterial and archaeal taxa were observed in different springs. Evaluation of the carbon, sulfur, and nitrogen metabolism in these hot spring communities has revealed diversity in terms of metabolic activity. Temperature seems to be an important factor in shaping the microbial communities of these springs. Overall, the diversity and richness of the microbiota are negatively affected by increasing temperature. Other abiotic factors, including pH, mineralization, and geological history, also impact the structure and function of the microbial community. More than 130 bacterial and archaeal strains (Bacillus, Geobacillus, Parageobacillus, Anoxybacillus, Paenibacillus, Brevibacillus Aeribacillus, Ureibacillus, Thermoactinomyces, Sporosarcina, Thermus, Rhodobacter, Thiospirillum, Thiocapsa, Rhodopseudomonas, Methylocaldum, Desulfomicrobium, Desulfovibrio, Treponema, Arcobacter, Nitropspira, and Methanoculleus) have been reported, some of which may be representative of novel species (sharing 91–97% sequence identity with their closest matches in GenBank) and producers of thermozymes and biomolecules with potential biotechnological applications. Whole-genome shotgun sequencing of T. scotoductus K1, as well as of the potentially new Treponema sp. J25 and Anoxybacillus sp. K1, were performed. Most of the phyla identified by 16S rRNA were also identified using metagenomic approaches. Detailed characterization of thermophilic isolates indicate the potential of the studied springs as a source of biotechnologically valuable microbes and biomolecules.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Takayuki Matsuoka ◽  
Takuya Shimizu ◽  
Tadanori Minagawa ◽  
Wakiko Hiranuma ◽  
Miki Takeda ◽  
...  

Abstract Background Bacteroides dorei is an anaerobic gram-negative bacterium first described in 2006. Because of the high similarity in mass spectra between B. dorei and Bacteroides vulgatus, discriminating between these species is arduous in clinical practice. In recent decades, 16S rRNA gene sequencing has been a complementary method for distinguishing taxonomically close bacteria, including B. dorei and B. vulgatus, at the genus and species levels. Consequently, B. dorei has been shown to contribute to some diseases, including type 1 autoimmune diabetes mellitus and atherosclerotic diseases. However, there are no reports on invasive infectious diseases caused by B. dorei. This report describes the first case of direct invasion and colonisation of human tissue by B. dorei, thus providing a warning regarding the previously proposed application of B. dorei as a live biotherapeutic for atherosclerotic diseases. Case presentation A 78-year-old Japanese man complained of intermittent chest/back pain and was diagnosed with a mycotic thoracic aortic aneurysm by enhanced computed tomography on admission. Despite strict blood pressure control and empirical antibiotic therapy, the patient’s condition worsened. To prevent aneurysmal rupture and eliminate infectious foci, the patient underwent surgical treatment. The resected specimen was subjected to tissue culture and 16S rRNA gene sequencing analysis to identify pathogenic bacteria. A few days after the surgery, culture and sequencing results revealed that the pathogen was B. dorei/B. vulgatus and B. dorei, respectively. The patient was successfully treated with appropriate antibacterial therapy and after improvement, was transferred to another hospital for rehabilitation on postoperative day 34. There was no recurrence of infection or aneurysm after the patient transfer. Conclusions This report describes the first case of invasive infectious disease caused by B. dorei, casting a shadow over its utilisation as a probiotic for atherosclerotic diseases.


2008 ◽  
Vol 74 (6) ◽  
pp. 1740-1747 ◽  
Author(s):  
Andrew Dopheide ◽  
Gavin Lear ◽  
Rebecca Stott ◽  
Gillian Lewis

ABSTRACT Free-living protozoa are thought to be of fundamental importance in aquatic ecosystems, but there is limited understanding of their diversity and ecological role, particularly in surface-associated communities such as biofilms. Existing eukaryote-specific PCR primers were used to survey 18S rRNA gene sequence diversity in stream biofilms but poorly revealed protozoan diversity, demonstrating a need for protozoan-targeted primers. Group-specific PCR primers targeting 18S rRNA genes of the protozoan phylum Ciliophora were therefore designed and tested using DNA extracted from cultured protozoan isolates. The two most reliable primer combinations were applied to stream biofilm DNA, followed by cloning and sequencing analysis. Of 44 clones derived from primer set 384F/1147R, 86% were of probable ciliate origin, as were 25% of 44 clones detected by primer set 121F/1147R. A further 29% of 121F/1147R-detected clones matched sequences from the closely related phylum Apicomplexa. The highly ciliate-specific primer set 384F/1147R was subsequently used in PCRs on biofilm DNA from four streams exhibiting different levels of human impact, revealing differences in ciliate sequence diversity in samples from each site. Of a total of 240 clones, 73% were of probable ciliate origin; 54 different putative ciliate sequences were detected from throughout seven taxonomic ciliate classes. Sequences from Oligohymenophorea were most commonly detected in all samples, followed by either Spirotrichea or Phyllopharyngea. Restriction fragment length polymorphism profile-based analysis of clones suggested a potentially higher level of diversity than did sequencing. Nevertheless, newly designed PCR primers 384F/1147R were considered to provide an effective molecular basis for characterization of ciliate diversity in stream biofilms.


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