scholarly journals Sequence and Phylogenetic Analysis of SSU rRNA Gene of Five Microsporidia

2009 ◽  
Vol 60 (1) ◽  
pp. 30-37 ◽  
Author(s):  
ShiNan Dong ◽  
ZhongYuan Shen ◽  
Li Xu ◽  
Feng Zhu
Diversity ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 198 ◽  
Author(s):  
Alexandra Y. Beliavskaia ◽  
Alexander V. Predeus ◽  
Sofya K. Garushyants ◽  
Maria D. Logacheva ◽  
Jun Gong ◽  
...  

Holospora-like bacteria (HLB) are obligate intracellular Alphaproteobacteria, inhabiting nuclei of Paramecium and other ciliates such as “Candidatus Hafkinia” is in Frontonia. The HLB clade is comprised of four genera, Holospora, Preeria, “Candidatus Gortzia”, and “Candidatus Hafkinia”. These bacteria have a peculiar life cycle with two morphological forms and some degree of specificity to the host species and the type of nucleus they inhabit. Here we describe a novel species of HLB—“Candidatus Gortzia yakutica” sp. nov.—a symbiont from the macronucleus of Paramecium putrinum, the first described HLB for this Paramecium species. The new endosymbiont shows morphological similarities with other HLB. The phylogenetic analysis of the SSU rRNA gene places it into the “Candidatus Gortzia” clade.


2008 ◽  
Vol 74 (12) ◽  
pp. 3710-3717 ◽  
Author(s):  
Jennifer J. Joyner ◽  
R. Wayne Litaker ◽  
Hans W. Paerl

ABSTRACT Dense blooms of the cyanobacterium Lyngbya wollei are increasingly responsible for declining water quality and habitat degradation in numerous springs, rivers, and reservoirs. This research represents the first molecular phylogenetic analysis of L. wollei in comparison with the traditional morphological characterization of this species. Specimens were collected from several springs in Florida and a reservoir in North Carolina. Segments of the small-subunit (SSU) rRNA and nifH genes were PCR amplified, cloned, and sequenced. The phylogenetic analysis of the SSU rRNA gene revealed sequences that fell into three distinct subclusters, each with >97% sequence similarity. These were designated operational taxonomic unit 1 (OTU1), OTU2, and OTU3. Similarly, the nifH sequences fell into three distinct subclusters named S1, S2, and S3. When either bulk samples or individual filaments were analyzed, we recovered OTU1 with S1, OTU2 with S2, and OTU3 with S3. The coherence between the three SSU rRNA gene and nifH subclusters was consistent with genetically distinct strains or species. Cells associated with subclusters OTU3 and S3 were significantly wider and longer than those associated with other subclusters. The combined molecular and morphological data indicate that the species commonly identified as L. wollei in the literature represents two or possibly more species. Springs containing OTU3 and S3 demonstrated lower ion concentrations than other collection sites. Geographical locations of Lyngbya subclusters did not correlate with residual dissolved inorganic nitrogen or phosphorus concentrations. This study emphasizes the need to complement traditional identification with molecular characterization to more definitively detect and characterize harmful cyanobacterial species or strains.


2007 ◽  
Vol 54 (4) ◽  
pp. 277-282 ◽  
Author(s):  
Anders Jorgensen ◽  
Anders Alfjorden ◽  
Kristin Henriksen ◽  
Erik Sterud

2013 ◽  
Vol 63 (Pt_12) ◽  
pp. 4669-4674 ◽  
Author(s):  
Véronique Guérin-Faublée ◽  
Jean-Pierre Flandrois ◽  
Catherine Pichat ◽  
Maria Laura Boschiroli ◽  
Brigitte Lamy

Three independent strains of a rapidly growing, non-chromogenic member of the genus Mycobacterium were isolated from lymph nodes of French cattle. Identification of the isolates was carried out using a polyphasic approach. The nearly complete SSU rRNA gene sequences (>1200 bp) of the strains MLB-A23, MLB-A30 and MLB-A84T were identical. A phylogenetic analysis of these unique SSU rRNA gene sequences showed that these strains were most closely related to Mycobacterium intermedium . Further phylogenetic analysis based on concatenated sequences (2854 bp) of four housekeeping genes (hsp65, rpoB, sodA and tuf), the transfer–messenger RNA (tmRNA) and SSU rRNA genes indicated that these three strains represented a distinct species that shares a common ancestor with M. intermedium . Phylogenetic and phenotypic data strongly indicate that the strains MLB-A23, MLB-A30 and MLB-A84T belong to a novel mycobacterial species for which the name Mycobacterium bourgelatii sp. nov. is proposed. The type strain is MLB-A84T ( = CIP 110557T = DSM 45746T).


Parasitology ◽  
2004 ◽  
Vol 130 (4) ◽  
pp. 405-412 ◽  
Author(s):  
W. C. GIBSON ◽  
J. LOM ◽  
H. PECKOVÁ ◽  
V. R. FERRIS ◽  
P. B. HAMILTON

The taxonomy and phylogenetic relationships of fish trypanosomes are uncertain. A collection of 22 cloned trypanosome isolates from 14 species of European freshwater fish and 1 species of African freshwater fish were examined by molecular phylogenetic analysis. The small subunit ribosomal RNA (ssu rRNA) genes of 8 clones were sequenced and compared with ssu rRNA gene sequences from a wider selection of vertebrate trypanosome isolates by phylogenetic analysis. All trypanosomes from freshwater fish fell in a single clade, subdivided into 3 groups. This clade sits within a larger, robust clade containing trypanosomes from marine fish and various amphibious vertebrates. All 22 trypanosome clones were analysed by random amplification of polymorphic DNA. The resulting dendrogram shows 3 groups, which are congruent with the groups identified in the ssu rRNA gene phylogeny. Two of the groups contain the majority of trypanosome isolates and within-group variation is slight. These groups do not separate purported trypanosome species distinguished by morphology or host origin, and thus these criteria do not appear to be reliable guides to genetic relationships among fish trypanosomes. However, we suggest that the 2 groups themselves may represent different species of fish trypanosomes. The polymorphic DNA markers we have identified will facilitate future comparisons of the biology of these 2 groups of fish trypanosomes.


2020 ◽  
Author(s):  
Joshua Ang Xin De ◽  
Khamisah Abdul Kadir ◽  
Dayang Shuaisah Awang Mohamad ◽  
Asmad Matusop ◽  
Paul Cliff Simon Divis ◽  
...  

Abstract Background: Plasmodium knowlesi is a significant cause of human malaria in Sarawak, Malaysian Borneo. Only one study has been previously undertaken in Sarawak to identify vectors of P. knowlesi , where Anopheles latens was incriminated as the vector in Kapit, central Sarawak. A study was therefore undertaken to identify malaria vectors in a different location in Sarawak. Methods: Mosquitoes found landing on humans and resting on leaves over a 5-day period at two sites in the Lawas District of northern Sarawak were collected and identified. DNA samples extracted from salivary glands of Anopheles mosquitoes were subjected to nested PCR malaria-detection assays. The small subunit ribosomal RNA ( SSU rRNA) gene of Plasmodium was sequenced, and the internal transcribed spacer 2 (ITS2) and mitochondrial cytochrome c oxidase subunit 1 ( cox 1) gene of the mosquitoes were sequenced from the Plasmodium -positive samples for phylogenetic analysis. Results: Totals of 65 anophelines and 127 culicines were collected. By PCR, 6 An. balabacensis and 5 An. donaldi were found to have single P. knowlesi infections while 3 other An. balabacensis had either single, double or triple infections with P. inui , P. fieldi , P. cynomolgi and P. knowlesi . Phylogenetic analysis of the Plasmodium SSU rRNA gene confirmed 3 An. donaldi and 3 An. balabacensis with single P. knowlesi infections, while 3 other An. balabacensis had two or more Plasmodium species of P. inui , P. knowlesi , P. cynomolgi and some species of Plasmodium that could not be conclusively identified. Phylogenies inferred from the ITS2 and/or cox 1 sequences of An. balabacensis and An. donaldi indicate that they are genetically indistinguishable from An. balabacensis and An. donaldi , respectively, found in Sabah, Malaysian Borneo. Conclusions: Previously An. latens was identified as the vector for P. knowlesi in Kapit, central Sarawak, Malaysian Borneo, and now An. balabacensis and An. donaldi have been incriminated as vectors for zoonotic malaria in Lawas, northern Sarawak.


1999 ◽  
Vol 35 (3) ◽  
pp. 458-465 ◽  
Author(s):  
Joon-seok Chae ◽  
Suryakant D. Waghela ◽  
Thomas M. Craig ◽  
Alan A. Kocan ◽  
Gerald G. Wagner ◽  
...  

2013 ◽  
Vol 60 (3) ◽  
pp. 135-148 ◽  
Author(s):  
Ioannis A. Papaioannou ◽  
Chrysoula D. Dimopoulou ◽  
Milton A. Typas

2018 ◽  
Author(s):  
Jeffrey S. McLean ◽  
Batbileg Bor ◽  
Thao T. To ◽  
Quanhui Liu ◽  
Kristopher A. Kerns ◽  
...  

ABSTRACTRecently, we discovered that a member of the Saccharibacteria/TM7 phylum (strain TM7x) isolated from the human oral cavity, has an ultra-small cell size (200-300nm), a highly reduced genome (705 Kbp) with limited de novo biosynthetic capabilities, and a very novel lifestyle as an obligate epibiont on the surface of another bacterium 1. There has been considerable interest in uncultivated phyla, particularly those that are now classified as the proposed candidate phyla radiation (CPR) reported to include 35 or more phyla and are estimated to make up nearly 15% of the domain Bacteria. Most members of the larger CPR group share genomic properties with Saccharibacteria including reduced genomes (<1Mbp) and lack of biosynthetic capabilities, yet to date, strain TM7x represents the only member of the CPR that has been cultivated and is one of only three CPR routinely detected in the human body. Through small subunit ribosomal RNA (SSU rRNA) gene surveys, members of the Saccharibacteria phylum are reported in many environments as well as within a diversity of host species and have been shown to increase dramatically in human oral and gut diseases. With a single copy of the 16S rRNA gene resolved on a few limited genomes, their absolute abundance is most often underestimated and their potential role in disease pathogenesis is therefore underappreciated. Despite being an obligate parasite dependent on other bacteria, six groups (G1-G6) are recognized using SSU rRNA gene phylogeny in the oral cavity alone. At present, only genomes from the G1 group, which includes related and remarkably syntenic environmental and human oral associated representatives1, have been uncovered to date. In this study we systematically captured the spectrum of known diversity in this phylum by reconstructing completely novel Class level genomes belonging to groups G3, G6 and G5 through cultivation enrichment and/or metagenomic binning from humans and mammalian rumen. Additional genomes for representatives of G1 were also obtained from modern oral plaque and ancient dental calculus. Comparative analysis revealed remarkable divergence in the host-associated members across this phylum. Within the human oral cavity alone, variation in as much as 70% of the genes from nearest oral clade (AAI 50%) as well as wide GC content variation is evident in these newly captured divergent members (G3, G5 and G6) with no environmental relatives. Comparative analyses suggest independent episodes of transmission of these TM7 groups into humans and convergent evolution of several key functions during adaptation within hosts. In addition, we provide evidence from in vivo collected samples that each of these major groups are ultra-small in size and are found attached to larger cells.


Sign in / Sign up

Export Citation Format

Share Document