Characterization of a mitochondrion-like organelle inCryptosporidium parvum

Parasitology ◽  
2004 ◽  
Vol 129 (1) ◽  
pp. 1-18 ◽  
Author(s):  
L. PUTIGNANI ◽  
A. TAIT ◽  
H. V. SMITH ◽  
D. HORNER ◽  
J. TOVAR ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Protozoan Parasite ◽  
Diarrhoeal Disease ◽  
Morphological Description ◽  
Detailed Knowledge ◽  
Degenerate Primers ◽  
Energy Filtering ◽  
Partial Cdna Sequence ◽  
Genes Encoding

Cryptosporidium parvumis a protozoan parasite that causes widespread diarrhoeal disease in humans and other animals and is responsible for large waterborne outbreaks of cryptosporidiosis. Unlike many organisms belonging to the phylum Apicomplexa, such asPlasmodiumspp. andToxoplasma gondii, there is no clinically proven drug treatment against this parasite. Aspects of the basic biology ofC. parvumremain poorly understood, including a detailed knowledge of key metabolic pathways, its genome organization and organellar complement. Previous studies have proposed thatC. parvumlacks a relic plastid organelle, or ‘apicoplast’, but that it may possess a mitochondrion. Here we characterize a mitochondrion-like organelle inC. parvumby (i) ultrastructural and morphological description (ii) localization of heterologous mitochondrial chaperonin antibody probes (iii) phylogenetic analysis of genes encoding mitochondrial transport proteins (iv) identification and analysis of mitochondrion-associated gene sequences. Our descriptive morphological analysis was performed by energy-filtering transmission electron microscopy (EFTEM) ofC. hominisandC. parvum. The ‘mitochondrion-like’ organelle was characterized by labelling the structure with a heterologous mitochondrial chaperonin probe (hsp60) both in immunoelectron microscopy (IMEM) and immunofluorescence (IMF). Phylogenetic analysis of the mitochondrial import system and housekeeping components (hsp60 and hsp70-dnaK) suggested that theC. parvummitochondrion-like organelle is likely to have descended from a common ancestral apicomplexan mitochondrion. We also identified a partial cDNA sequence coding for an alternative oxidase (AOX) gene, a component of the electron transport chain which can act as an alternative to the terminal mitochondrial respiratory complexes III and IV, which has not yet been reported in any other member of this phylum. Degenerate primers developed to identify selected mitochondrial genes failed to identify either cytochrome oxidase subunit I, or cytochrome b. Taken together, our data aim to provide new insights into the characterization of thisCryptosporidiumorganelle and a logical framework for future functional investigation.

scholarly journals New Strategy for Identification of Novel cry-Type Genes from Bacillus thuringiensis Strains

2005 ◽  
Vol 71 (2) ◽  
pp. 761-765 ◽  
Author(s):  
Corina M. Berón ◽  
Leonardo Curatti ◽  
Graciela L. Salerno
Keyword(s):  
Bacillus Thuringiensis ◽  
Phylogenetic Distance ◽  
Cloning And Sequencing ◽  
Degenerate Primers ◽  
Dna Templates ◽  
Cry Proteins ◽  
New Strategy ◽  
Genes Encoding ◽  
Encoding Protein

ABSTRACT We designed five degenerate primers for detection of novel cry genes from Bacillus thuringiensis strains. An efficient strategy was developed based on a two-step PCR approach with these primers in five pair combinations. In the first step, only one of the primer pairs is used in the PCR, which allows amplification of DNA fragments encoding protein regions that include consensus domains of representative proteins belonging to different Cry groups. A second PCR is performed by using the first-step amplification products as DNA templates and the set of five primer combinations. Cloning and sequencing of the last-step amplicons allow both the identification of known cry genes encoding Cry proteins covering a wide phylogenetic distance and the detection and characterization of cry-related sequences from novel B. thuringiensis isolates.

scholarly journals Identification of Streptococci to Species Level by Sequencing the Gene Encoding the Manganese-Dependent Superoxide Dismutase

1998 ◽  
Vol 36 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Claire Poyart ◽  
Gilles Quesne ◽  
Stephane Coulon ◽  
Patrick Berche ◽  
Patrick Trieu-Cuot
Keyword(s):  
Superoxide Dismutase ◽  
Pcr Assay ◽  
Degenerate Primers ◽  
Gene Encoding ◽  
Genes Encoding ◽  
Type Strains ◽  
Internal Fragment ◽  
Rrna Sequences ◽  
16S Rrna Sequences

We have used a PCR assay based on the use of degenerate primers in order to characterize an internal fragment (sodAint ) representing approximately 85% of the genes encoding the manganese-dependent superoxide dismutase in various streptococcal type strains (S. acidominimus,S. agalactiae, S. alactolyticus, S. anginosus, S. bovis, S. constellatus,S. canis, S. cricetus, S. downei,S. dysgalactiae, S. equi subsp.equi, S. equi subsp. zooepidemicus,S. equinus, S. gordonii, S. iniae,S. intermedius, S. mitis, S. mutans, S. oralis, S. parasanguis,S. pneumoniae, S. porcinus, S. pyogenes, S. salivarius, S. sanguis,S. sobrinus, S. suis, S. thermophilus, and S. vestibularis). Phylogenetic analysis of these sodAint fragments yields an evolutionary tree having a topology similar to that of the tree constructed with the 16S rRNA sequences. We have shown that clinical isolates could be identified by determining the positions of theirsodAint fragments on the phylogenetic tree of the sodAint fragments of the type species. We propose this method for the characterization of strains that cannot be assigned to a species on the basis of their conventional phenotypic reactions.

scholarly journals Characterization of actin genes in Bonamia ostreae and their application to phylogeny of the Haplosporidia

Parasitology ◽  
2007 ◽  
Vol 134 (14) ◽  
pp. 1941-1948 ◽  
Author(s):  
I. LÓPEZ-FLORES ◽  
V. N. SUÁREZ-SANTIAGO ◽  
D. LONGET ◽  
D. SAULNIER ◽  
B. CHOLLET ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Protozoan Parasite ◽  
Ostrea Edulis ◽  
Coding Region ◽  
Actin Genes ◽  
Bonamia Ostreae ◽  
Flat Oyster ◽  
Primer Sets ◽  
Systemic Infections

SUMMARYBonamia ostreae is a protozoan parasite that infects the European flat oyster Ostrea edulis, causing systemic infections and resulting in massive mortalities in populations of this valuable bivalve species. In this work, we have characterized B. ostreae actin genes and used their sequences for a phylogenetic analysis. Design of different primer sets was necessary to amplify the central coding region of actin genes of B. ostreae. Characterization of the sequences and their amplification in different samples demonstrated the presence of 2 intragenomic actin genes in B. ostreae, without any intron. The phylogenetic analysis placed B. ostreae in a clade with Minchinia tapetis, Minchinia teredinis and Haplosporidium costale as its closest relatives, and demonstrated that the paralogous actin genes found in Bonamia resulted from a duplication of the original actin gene after the Bonamia origin.

scholarly journals Polycyclic Aromatic Hydrocarbon Degradation by a New Marine Bacterium, Neptunomonas naphthovorans gen. nov., sp. nov

1999 ◽  
Vol 65 (1) ◽  
pp. 251-259 ◽  
Author(s):  
Brian P. Hedlund ◽  
Allison D. Geiselbrecht ◽  
Timothy J. Bair ◽  
James T. Staley
Keyword(s):  
Phylogenetic Analysis ◽  
Amino Acid ◽  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Puget Sound ◽  
Amino Acid Sequences ◽  
Genotypic Differences ◽  
Degenerate Primers ◽  
Genes Encoding ◽  
Polycyclic Aromatic

ABSTRACT Two strains of bacteria were isolated from creosote-contaminated Puget Sound sediment based on their ability to utilize naphthalene as a sole carbon and energy source. When incubated with a polycyclic aromatic hydrocarbon (PAH) compound in artificial seawater, each strain also degraded 2-methylnaphthalene and 1-methylnaphthalene; in addition, one strain, NAG-2N-113, degraded 2,6-dimethylnaphthalene and phenanthrene. Acenaphthene was not degraded when it was used as a sole carbon source but was degraded by both strains when it was incubated with a mixture of seven other PAHs. Degenerate primers and the PCR were used to isolate a portion of a naphthalene dioxygenase iron-sulfur protein (ISP) gene from each of the strains. A phylogenetic analysis of PAH dioxygenase ISP deduced amino acid sequences showed that the genes isolated in this study were distantly related to the genes encoding naphthalene dioxygenases of Pseudomonas andBurkholderia strains. Despite the differences in PAH degradation phenotype between the new strains, the dioxygenase ISP deduced amino acid fragments of these organisms were 97.6% identical. 16S ribosomal DNA-based phylogenetic analysis placed these bacteria in the gamma-3 subgroup of the Proteobacteria, most closely related to members of the genus Oceanospirillum. However, morphologic, physiologic, and genotypic differences between the new strains and the oceanospirilla justify the creation of a novel genus and species, Neptunomonas naphthovorans. The type strain ofN. naphthovorans is strain NAG-2N-126.

Morphological, histological and molecular characterization of Myxidium cf. rhodei infecting the kidney of Rutilus rutilus

2020 ◽  
Vol 141 ◽  
pp. 39-46
Author(s):  
MD Dorjievna Batueva ◽  
X Pan ◽  
J Zhang ◽  
X Liu ◽  
W Wei ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Molecular Characterization ◽  
Rutilus Rutilus ◽  
Longitudinal Axis ◽  
Suture Line ◽  
Present Species ◽  
Supplementary Data

In the present study, we provide supplementary data for Myxidium cf. rhodei Léger, 1905 based on morphological, histological and molecular characterization. M. cf. rhodei was observed in the kidneys of 918 out of 942 (97%) roach Rutilus rutilus (Linnaeus, 1758). Myxospores of M. cf. rhodei were fusiform with pointed ends, measuring 12.7 ± 0.1 SD (11.8-13.4) µm in length and 4.6 ± 0.1 (3.8-5.4) µm in width. Two similar pear-shaped polar capsules were positioned at either ends of the longitudinal axis of the myxospore: each of these capsules measured 4.0 ± 0.1 (3.1-4.7) µm in length and 2.8 ± 0.1 (2.0-4.0) µm in width. Polar filaments were coiled into 4 to 5 turns. Approximately 18-20 longitudinal straight ridges were observed on the myxospore surface. The suture line was straight and distinctive, running near the middle of the valves. Histologically, the plasmodia of the present species were found in the Bowman’s capsules, and rarely in the interstitium of the host. Phylogenetic analysis revealed that M. cf. rhodei was sister to M. anatidum in the Myxidium clade including most Myxidium species from freshwater hosts.

Isolation and characterization of the genes encoding antimicrobial neutrophil cationic peptides, defensins.

Ensho ◽  
1995 ◽  
Vol 15 (1) ◽  
pp. 33-41
Author(s):  
Isao Nagaoka ◽  
Noriko Ishihara ◽  
Akimasa Someya ◽  
Kazuhisa Iwabuchi ◽  
Shin Yomogida ◽  
...  
Keyword(s):  
Cationic Peptides ◽  
Isolation And Characterization ◽  
Genes Encoding

scholarly journals Protein complex formation in methionine chain-elongation and leucine biosynthesis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Li-Qun Chen ◽  
Shweta Chhajed ◽  
Tong Zhang ◽  
Joseph M. Collins ◽  
Qiuying Pang ◽  
...  
Keyword(s):  
Protein Complexes ◽  
Complete Characterization ◽  
Bimolecular Fluorescence Complementation ◽  
Chain Elongation ◽  
Substrate Channeling ◽  
Leucine Biosynthesis ◽  
Protein Complex Formation ◽  
Genes Encoding ◽  
Isopropylmalate Dehydrogenase

AbstractDuring the past two decades, glucosinolate (GLS) metabolic pathways have been under extensive studies because of the importance of the specialized metabolites in plant defense against herbivores and pathogens. The studies have led to a nearly complete characterization of biosynthetic genes in the reference plant Arabidopsis thaliana. Before methionine incorporation into the core structure of aliphatic GLS, it undergoes chain-elongation through an iterative three-step process recruited from leucine biosynthesis. Although enzymes catalyzing each step of the reaction have been characterized, the regulatory mode is largely unknown. In this study, using three independent approaches, yeast two-hybrid (Y2H), coimmunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC), we uncovered the presence of protein complexes consisting of isopropylmalate isomerase (IPMI) and isopropylmalate dehydrogenase (IPMDH). In addition, simultaneous decreases in both IPMI and IPMDH activities in a leuc:ipmdh1 double mutants resulted in aggregated changes of GLS profiles compared to either leuc or ipmdh1 single mutants. Although the biological importance of the formation of IPMI and IPMDH protein complexes has not been documented in any organisms, these complexes may represent a new regulatory mechanism of substrate channeling in GLS and/or leucine biosynthesis. Since genes encoding the two enzymes are widely distributed in eukaryotic and prokaryotic genomes, such complexes may have universal significance in the regulation of leucine biosynthesis.

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