Synthetic Biology and the United Nations Lai, Hung-En; Canavan, Caoimhe; Cameron, Loren ...
Trends in biotechnology (Regular ed.),
11/2019, Letnik:
37, Številka:
11
Journal Article
Recenzirano
Odprti dostop
Synthetic biology is a rapidly emerging interdisciplinary field of science and engineering that aims to redesign living systems through reprogramming genetic information. The field has catalysed ...global debate among policymakers and publics. Here we describe how synthetic biology relates to these international deliberations, particularly the Convention on Biological Diversity (CBD).
As a result of migrations and globalization, people may face a possible increase in the incidence of central nervous system rickettsial infections (CNS R). These diseases, caused by Rickettsia ...species and transmitted to humans by arthropod bites, are putatively lethal. However, the diagnosis of CNS R is challenging and often delayed due to their nonspecific clinical presentation and the strict intracellular nature of rickettsiae. Furthermore, transfer of rickettsiae to the brain parenchyma is not yet understood. The aim of this review is to analyze and summarize the features and correlated findings of CNS R in order to focus attention on these intriguing but frequently neglected illnesses. We also incorporated data on CNS infections caused by Rickettsia-related microorganisms.
Arsenophonus nasoniae, a male-killing endosymbiont of chalcid wasps, was recently detected in several hard tick species. Following the hypothesis that its presence in ticks may not be linked to the ...direct occurrence of bacteria in tick's organs, we identified A. nasoniae in wasps emerging from parasitised nymphs. We confirmed that 28.1% of Ixodiphagus hookeri wasps parasitizing Ixodes ricinus ticks were infected by A. nasoniae. Moreover, in examined I. ricinus nymphs, A. nasoniae was detected only in those, which were parasitized by the wasp. However, in part of the adult wasps as well as in some ticks that contained wasp's DNA, we did not confirm A. nasoniae. We also found, that in spite of reported male-killing, some newly emerged adult wasp males were also infected by A. nasoniae. Additionally, we amplified the DNA of Rickettsia helvetica and Rickettsia monacensis (known to be Ixodes ricinus-associated bacteria) in adult parasitoid wasps. This may be related either with the digested bacterial DNA in wasp body lumen or with a role of wasps in circulation of rickettsiae among tick vectors.
Culture Isolate of Rickettsia felis from a Tick Danchenko, Monika; Benada, Oldřich; Škultéty, Ľudovít ...
International journal of environmental research and public health,
04/2022, Letnik:
19, Številka:
7
Journal Article
Recenzirano
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Although the cat flea,
, has been identified as the primary vector of
, additional flea, tick, mite, and louse species have also been associated with this bacterium by molecular means; however, the ...role of these arthropods in the transmission of
has not been clarified. Here, we succeeded in culture isolation of
from a host-seeking castor bean tick,
, the most common tick in Slovakia. The bacterial isolation was performed on XTC-2 cells at 28 °C using the shell-vial technique. An evaluation of the growth properties was performed for both the XTC-2 and Vero cell lines. We observed
in the infected host cells microscopically by Gimenez staining and immunofluorescence assay. The
isolate was purified by gradient ultracentrifugation and visualized by electron microscopy. Fragments of the genes
A,
A,
B,
A,
B,
4,
E, and
were amplified and compared with the corresponding sequences of the type strain URRWXCal2 and other
culture -isolated strains. We did not detect any nucleotide polymorphisms; however, plasmid pRFδ, characteristic of the standard strain, was absent in our isolate. Herein, we describe the first successful isolation and characterization of a tick-derived
strain "Danube", obtained from an
nymph.
The objective was to investigate fixative solutions: 3.7% formaldehyde, 4% paraformaldehyde, 4% paraformaldehyde in the cytoskeletal buffer and 4% paraformaldehyde in PHEM buffer (containing PIPES, ...HEPES, EGTA and MgCl
), applicable for immunofluorescence assay.
Herein we optimized this serological technique, testing four fixative solutions, for the sensitive detection of rickettsial antigens, and preservation of intracellular structures of the host cells, particularly filamentous actin. Rickettsial antigens were presented equally well both with formaldehyde and all paraformaldehyde-based fixations, but only protocol with 4% paraformaldehyde in PHEM buffer allowed accurate imaging of actin filaments, and simultaneously allows monitoring of rickettsiae using actin-based motility during infection inside the host cells.
Ticks are vector arthropods responsible for the transmission of several pathogenic agents that affect both human and animal health worldwide. In this study our objective was to analyse, using ...molecular tools, the bacterial community of
Dermacentor reticulatus
and
Haemaphysalis inermis
ticks collected in south-eastern Slovakia. Using real-time PCR, we identified the presence of
Rickettsia
spp. DNA at levels of 14/59 (23.72 %) and 29/173 (16.76 %) in
D. reticulatus
and
H. inermis
, respectively. In addition, using standard PCR and sequencing, we identified the presence of
Rickettsia raoultii
DNA in 13 ticks belonging to the two investigated species.
Rickettsia raoultii
blast results revealed an average identification percentage of 99.62 %. Following the results of this molecular study there is a possibility that
D. reticulatus
and
H. inermis
play a potential role in the transmission of
R. raoultii
. To prove the possibility of validity of this hypothesis, we suggest performing experimental models in future studies. Our results can serve as preliminary data for future transmission models.
Eighty Ixodes ricinus ticks collected in the Rovinka forest in Slovakia were tested by real-time and routine single-step PCR for the presence of different pathogenic and endosymbiotic bacteria. No ...evidence of Coxiella burnetii, Diplorickettsia massiliensis, or Bartonella spp. was found. However, we identified, as the pathogenic bacteria, Anaplasma phagocytophilum in 8%, Rickettsia helvetica in 11%, Borrelia afzelii in 9%, Bo. garinii in 8%, Bo. burgdorferi sensu stricto in 5%, Bo. valaisiana in 3%, and Bo. miyamotoi in 1% of ticks. Other bacteria with unknown or suspected pathogenicity for humans were also identified: Arsenophonus nasoniae in 25%, Spiroplasma ixodetis in 3%, Candidatus Midichloria mitochondrii in 4%, Wolbachia aff. pipientis in 14%, and Ehrlichia muris in 3% of ticks. A. nasoniae was found almost exclusively in nymphs, and E. muris was only found in adult ticks. In total, 65% of ticks contained at least one species of bacteria, and 16% contained 2 or more species.
Obligate intracellular bacteria of arthropods often exhibit a significant role in either human health or arthropod ecology.
An obligate intracellular gamma-proteobacterium was isolated from the ...actively questing hard tick Ixodes ricinus using mammalian and amphibian cell lines. Transmission electron microscopy revealed a unique morphology of the bacterium, including intravacuolar localization of bacteria grouped predominantly in pairs and internal structures composed of electron-dense crystal-like structures and regular multilayer sheath-like structures. The isolate 20B was characterized to determine its taxonomic position using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that this strain belongs to the family Coxiellaceae, order Legionellales of Gamma-proteobacteria, and the closest relatives are different Rickettsiella spp. The level of 16S rRNA gene sequence similarity between strain 20B and other recognized species of the family was below 94.5%. Partial sequences of the rpoB, parC and ftsY genes confirmed the phylogenetic position of the new isolate. The G+C content estimated on the basis of whole genome analysis of strain 20B was 37.88%. On the basis of its phenotypic and genotypic properties, together with phylogenetic distinctiveness, we propose that strain 20B to be classified in the new genus Diplorickettsia as the type strain of a novel species named Diplorickettsia massiliensis sp. nov.
Considering the source of its isolation (hard tick, often biting humans) the role of this bacterium in the pathology of humans, animals and ticks should be further investigated.
Rickettsial infections of the central nervous system (CNS) are manifested by severe neurological symptoms and represent a serious life-threatening condition. Despite the considerable health danger, ...only a few studies have been conducted focusing on the pathogenesis induced by
sp. in CNS. To investigate the signaling pathways associated with the neurotoxic effects of rickettsiae, we employed an experimental model of cerebrocortical neurons combined with molecular profiling and comprehensive bioinformatic analysis. The cytopathic effect induced by
and
was demonstrated by decreased neuronal viability, structural changes in cell morphology, and extensive fragmentation of neurites in vitro. Targeted profiling revealed the deregulation of genes involved in the neuroinflammatory and neurotoxic cell response pathways. Although quantitative analysis showed differences in gene expression response, functional annotation revealed that the biological processes are largely shared between both
species. The identified enriched pathways are associated with cytokine signaling, chemotaxis of immune cells, responses to infectious agents, interactions between neurons, endothelial and glial cells, and regulation of neuronal apoptotic processes. The findings of our study provide new insight into the etiopathogenesis of CNS infection and further expand the understanding of molecular signaling associated with neuroinvasive
species.
Coxiella burnetii is a strict intracellular bacterium with potential as a bioterrorism agent. To characterize different isolates of C. burnetii at the molecular level, we performed multispacer ...sequence typing (MST). MST is based on intergenic region sequencing. These regions are potentially variable since they are subject to lower selection pressure than the adjacent genes. We screened 68 spacers in 14 isolates and selected the 10 that exhibited the most variation. These spacers were then tested in 159 additional isolates obtained from different geographic areas or different hosts or were implicated in different manifestations of human disease caused by C. burnetii. The sequence analysis yielded 30 different allelic combinations. Phylogenic analysis showed 3 major clusters. MST allows easy comparison and exchange of results obtained in different laboratories and could be a useful tool for identifying bacterial strains.
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