scholarly journals Domain Organization and Evolution of Multifunctional Autoprocessing Repeats-in-Toxin (MARTX) Toxin inVibrio vulnificus

2010 ◽  
Vol 77 (2) ◽  
pp. 657-668 ◽  
Author(s):  
Francisco J. Roig ◽  
Fernando González-Candelas ◽  
Carmen Amaro
Keyword(s):  
Evolutionary History ◽  
Vibrio Vulnificus ◽  
Rho Gtpase ◽  
Type Ii ◽  
Protease Domain ◽  
Domain Organization ◽  
Different Types ◽  
Domain Of Unknown Function ◽  
History Of ◽  
Cysteine Protease Domain

ABSTRACTThe objective of this study was to analyze multifunctional autoprocessing repeats-in-toxin (MARTX) toxin domain organization within the aquatic speciesVibrio vulnificusas well as to study the evolution of thertxA1gene. The species is subdivided into three biotypes that differ in host range and geographical distribution. We have found three different types (I, II, and III) ofV. vulnificusMARTX (MARTXVv) toxins with common domains (an autocatalytic cysteine protease domain [CPD], an α/β-hydrolase domain, and a domain resembling that of the LifA protein ofEscherichia coliO127:H6 E2348/69 [Efa/LifA]) and specific domains (a Rho-GTPase inactivation domain [RID], a domain of unknown function [DUF],a domain resembling that of thertxAprotein ofPhotorhabdus asymbiotica[rtxAPA], and an actin cross-linking domain [ACD]). Biotype 1 isolates harbor MARTXVvtoxin types I and II, biotype 2 isolates carry MARTXVvtoxin type III, and biotype 3 isolates have MARTXVvtoxin type II. The analyzed biotype 2 isolates harbor two identical copies ofrtxA1, one chromosomal and the other plasmidic. The evolutionary history of the gene demonstrates that MARTXVvtoxins are mosaics, comprising pieces with different evolutionary histories, some of which have been acquired by intra- or interspecific horizontal gene transfer. Finally, we have found evidence that the evolutionary history of thertxA1gene for biotype 2 differs totally from the gene history of biotypes 1 and 3.

Molecular phylogeny of diploid Hordeum species and incongruence between chloroplast and nuclear datasets

Genome ◽  
2011 ◽  
Vol 54 (12) ◽  
pp. 986-992 ◽  
Author(s):  
Huan Wang ◽  
Dongfa Sun ◽  
Genlou Sun
Keyword(s):  
Evolutionary History ◽  
Nuclear Gene ◽  
Intergenic Spacer ◽  
Molecular Data ◽  
Genome Species ◽  
Different Types ◽  
History Of ◽  
Morphological And Molecular Data ◽  
Hordeum Species ◽  
Eurasian Species

The phylogeny of diploid Hordeum species has been studied using both chloroplast and nuclear gene sequences. However, the studies of different nuclear datasets of Hordeum species often arrived at similar conclusions, whereas the studies of different chloroplast DNA data generally resulted in inconsistent conclusions. Although the monophyly of the genus is well supported by both morphological and molecular data, the intrageneric phylogeny is still a matter of controversy. To better understand the evolutionary history of Hordeum species, two chloroplast gene loci (trnD-trnT intergenic spacer and rps16 gene) and one nuclear marker (thioreoxin-like gene (HTL)) were used to explore the phylogeny of Hordeum species. Two obviously different types of trnD-trnT sequences were observed, with an approximately 210 base pair difference between these two types: one for American species, another for Eurasian species. The trnD-trnT data generally separated the diploid Hordeum species into Eurasian and American clades, with the exception of Hordeum marinum subsp. gussoneanum. The rps16 data also grouped most American species together and suggested that Hordeum flexuosum has a different plastid type from the remaining American species. The nuclear gene HTL data clearly divided Hordeum species into two clades: the Xu + H genome clade and the Xa + I genome clade. Within clades, H genome species were well separated from the Xu species, and the I genome species were well separated from the Xa genome species. The incongruence between chloroplast and nuclear datasets was found and discussed.

scholarly journals Unusual presentation of vitamin D3-dependent rickets type II in a kitten

2020 ◽  
Vol 6 (1) ◽  
pp. 205511692091027
Author(s):  
Florent Duplan ◽  
Christina Maunder
Keyword(s):  
Vitamin D ◽  
Positive Response ◽  
Abdominal Distension ◽  
Response To Treatment ◽  
Type I ◽  
Type Ii ◽  
Different Types ◽  
History Of ◽  
Radiographic Changes

Case summary A 15-week-old kitten presented with a 1-month history of intermittent generalised tremors and abdominal distension. Hypocalcaemia associated with increased 1,25-vitamin D3 was consistent with vitamin D3-dependent rickets type II. The bone appearance on CT scan was most consistent with the changes typically seen with nutritional secondary hyperparathyroidism and less typical of the changes seen with rickets. Our patient had a positive response to high vitamin D3 therapy as it remained normocalcaemic 16 months after diagnosis, supporting the diagnosis of rickets. Relevance and novel information This case report is an unusual and interesting presentation of rickets in a kitten. Despite the characteristic vitamin D3 disturbance for rickets type II, the atypical radiographic changes have not been previously reported. In the literature, a positive response to treatment is not commonly seen or follow-up is short. Our case responded well to treatment and was followed for 16 months from the time of diagnosis. This emphasises that the pathophysiology of the condition is not well understood, and that different types of vitamin D3-dependent rickets type II may exist. Although the genetic defects responsible for some cases of rickets type I have been identified, this has still not been determined for rickets type II.

scholarly journals Evolutionary history of the MTG gene family in vertebrates

2019 ◽  
Vol 64 (4) ◽  
pp. 391-402
Author(s):  
A. I. Kavaleuskaya ◽  
T. V. Ramanouskaya
Keyword(s):  
Gene Family ◽  
Evolutionary History ◽  
Protein Sequences ◽  
Stem Cell Differentiation ◽  
Gene Products ◽  
Functional Diversification ◽  
Rates Of Evolution ◽  
Different Types ◽  
History Of ◽  
Transcriptional Corepressors

The highly conserved MTG gene family includes three homologs in vertebrates (MTG8, MTGR1, MTG16) encoding transcriptional corepressors, which are important in haemopoiesis, neurogenesis and epithelial stem cell differentiation. These genes are of particular interest because they are involved in translocations, associated with different types of cancer. Looking at how this gene family evolved might provide insights into history of its structural and functional diversification. We have performed a phylogenetic analysis of MTG nucleotide and protein sequences to examine the evolutionary events. The domain organization of MTG gene products was clarified, the mechanism of appearance of the first MTG gene was revealed and the ancestor taxon was determined. Also the mechanism of MTG gene family emergence was established. In addition, analysis of the rates of evolution acting on individual domains was made, and conservative positions within each gene of MTG family were determined.

scholarly journals Exploring the evolutionary history of centrosomes

2014 ◽  
Vol 369 (1650) ◽  
pp. 20130453 ◽  
Author(s):  
Juliette Azimzadeh
Keyword(s):  
Cell Cycle ◽  
Nuclear Envelope ◽  
Evolutionary History ◽  
Structural Diversity ◽  
Structure And Function ◽  
Different Types ◽  
History Of ◽  
Tight Association ◽  
And Function ◽  
Molecular Components

The centrosome is the main organizer of the microtubule cytoskeleton in animals, higher fungi and several other eukaryotic lineages. Centrosomes are usually located at the centre of cell in tight association with the nuclear envelope and duplicate at each cell cycle. Despite a great structural diversity between the different types of centrosomes, they are functionally equivalent and share at least some of their molecular components. In this paper, we explore the evolutionary origin of the different centrosomes, in an attempt to understand whether they are derived from an ancestral centrosome or evolved independently from the motile apparatus of distinct flagellated ancestors. We then discuss the evolution of centrosome structure and function within the animal lineage.

Erythrocyte uroporphyrinogen decarboxylase activity and therapeutic phlebotomy in porphyria cutanea tarda

2000 ◽  
Vol 04 (08) ◽  
pp. 736-738
Author(s):  
FERENC KÓSZÓ ◽  
MÁRTA MORVAY ◽  
ATTILA DOBOZY ◽  
KRISZTINA BODA
Keyword(s):  
Porphyria Cutanea Tarda ◽  
Decarboxylase Activity ◽  
Type I ◽  
Type Ii ◽  
Uroporphyrinogen Decarboxylase ◽  
The Family ◽  
Different Types ◽  
History Of ◽  
A Minor ◽  
Genetically Determined

On the basis of the uroporphyrinogen decarboxylase ( UD ) activity in the erythrocytes, and the family history of the disease, different types of porphyria cutanea tarda ( PCT ) can be distinguished. In some cases, however, the distinction may involve some uncertainty (overlapping of subgroups). The question arises of whether the current erythrocyte UD activities in the different types of PCT are determined merely genetically. The erythrocyte UD activities in 72 unrelated patients with different forms of PCT (62 with type I PCT and 10 with type II PCT ), in different stages of the disease, were measured in order to test whether the activity exhibits any change during the long period of recovery. In both types the activities were faintly but significantly increased, from 94.9% (in PCT I) or 54.3% (in PCT II) up to 98.4% or 56.1% respectively. In both types the lower activity in the untreated condition can be attributed to a combination of several factors, including oxidative damage to UD , which results in a minor additional inhibition of the genetically determined enzyme activities.

scholarly journals Hiding in the swamp: new capillariid nematode parasitizing New Zealand brown mudfish

2017 ◽  
Vol 92 (3) ◽  
pp. 379-386
Author(s):  
F. Jorge ◽  
R.S.A. White ◽  
R.A. Paterson
Keyword(s):  
New Zealand ◽  
Evolutionary History ◽  
Fish Community ◽  
Phylogenetic Position ◽  
Fish Parasite ◽  
Swim Bladder ◽  
Parasite Diversity ◽  
Different Types ◽  
History Of ◽  
Host Parasite

AbstractThe extent of New Zealand's freshwater fish-parasite diversity has yet to be fully revealed, with host–parasite relationships still to be described from nearly half the known fish community. While advances in the number of fish species examined and parasite taxa described are being made, some parasite groups, such as nematodes, remain poorly understood. In the present study we combined morphological and molecular analyses to characterize a capillariid nematode found infecting the swim bladder of the brown mudfish Neochanna apoda, an endemic New Zealand fish from peat-swamp-forests. Morphologically, the studied nematodes are distinct from other Capillariinae taxa by the features of the male posterior end, namely the shape of the bursa lobes, and shape of spicule distal end. Male specimens were classified into three different types according to differences in the shape of the bursa lobes at the posterior end, but only one was successfully characterized molecularly. Molecular analysis indicated that the studied capillariid is distinct from other genera. However, inferences about the phylogenetic position of the capillariid reported here will remain uncertain, due to the limited number of Capillariinae taxa characterized molecularly. The discovery of this new capillariid, which atypically infects the swim bladder of its host, which itself inhabits a very unique ecosystem, underlines the very interesting evolutionary history of this parasite, which for now will remain unresolved.

scholarly journals Distinct Roles of the Repeat-Containing Regions and Effector Domains of the Vibrio vulnificus Multifunctional-Autoprocessing Repeats-in-Toxin (MARTX) Toxin

mBio ◽  
2015 ◽  
Vol 6 (2) ◽  
Author(s):  
Byoung Sik Kim ◽  
Hannah E. Gavin ◽  
Karla J. F. Satchell
Keyword(s):  
Cysteine Protease ◽  
Vibrio Vulnificus ◽  
Terminal Repeat ◽  
Protease Domain ◽  
Content Type ◽  
Effector Domains ◽  
Amino Terminal ◽  
Toxin Secretion ◽  
Cysteine Protease Domain ◽  
Carboxyl Terminal

ABSTRACTVibrio vulnificusis a seafood-borne pathogen that destroys the intestinal epithelium, leading to rapid bacterial dissemination and death. The most important virulence factor is the multifunctional-autoprocessing repeats-in-toxin (MARTX) toxin comprised of effector domains in the center region flanked by long repeat-containing regions which are well conserved among MARTX toxins and predicted to translocate effector domains. Here, we examined the role of the repeat-containing regions using a modifiedV. vulnificusMARTX (MARTXVv) toxin generated by replacing all the internal effector domains with β-lactamase (Bla). Bla activity was detected in secretions from the bacterium and also in the cytosol of intoxicated epithelial cells. The modified MARTXVvtoxin without effector domains retained its necrotic activity but lost its cell-rounding activity. Further, deletion of the carboxyl-terminal repeat-containing region blocked toxin secretion from the bacterium. Deletion of the amino-terminal repeat-containing region had no effect on secretion but completely abolished translocation and necrosis. Neither secretion nor translocation was affected by enzymatically inactivating the cysteine protease domain of the toxin. These data demonstrate that the amino-terminal and carboxyl-terminal repeat-containing regions of the MARTXVvtoxin are necessary and sufficient for the delivery of effector domains and epithelial cell lysisin vitrobut that effector domains are required for other cytopathic functions. Furthermore, Ca2+-dependent secretion of the modified MARTXVvtoxin suggests that nonclassical RTX-like repeats found in the carboxyl-terminal repeat-containing region are functionally similar to classical RTX repeats found in other RTX proteins.IMPORTANCEUp to 95% of deaths from seafood-borne infections in the United States are due solely to one pathogen,V. vulnificus. Among its various virulence factors, the MARTXVvtoxin has been characterized as a critical exotoxin for successful pathogenesis ofV. vulnificusin mouse infection models. Similarly to MARTX toxins of other pathogens, MARTXVvtoxin is comprised of repeat-containing regions, central effector domains, and an autoprocessing cysteine protease domain. Yet how each of these regions contributes to essential activities of the toxins has not been fully identified for any of MARTX toxins. Using modified MARTXVvtoxin fused with β-lactamase as a reporter enzyme, the portion(s) responsible for toxin secretion from bacteria, effector domain translocation into host cells, rapid host cell rounding, and necrotic host cell death was identified. The results are relevant for understanding how MARTXVvtoxin serves as both a necrotic pore-forming toxin and an effector delivery platform.

scholarly journals Populations of X-ray Binaries and the Dynamical History of their Host Galaxies

2001 ◽  
Vol 18 (4) ◽  
pp. 443-450 ◽  
Author(s):  
Kinwah Wu
Keyword(s):  
Evolutionary History ◽  
Host Galaxies ◽  
Host Environment ◽  
X Ray ◽  
Different Types ◽  
History Of ◽  
Nearby Galaxies ◽  
X Ray Binaries ◽  
Birth Death

AbstractThe observed luminosity distributions of X-ray sources indicate the presence of several populations of X-ray binaries in the nearby galaxies. Each population has its formation and evolutionary history, depending on the host environment. The features seen in the log N(>S)–log S curves for different types of galaxies and for different galactic components can be reproduced by a birth–death model, in which the lifespans of the binaries are inversely proportional to their X-ray brightness. Conversely, the dynamical history of a galaxy can be inferred from the luminosity distributions of its X-ray binary populations.

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