scholarly journals Infection Dynamics of Coexisting Beta- and Gammaproteobacteria in the Nested Endosymbiotic System of Mealybugs

2008 ◽  
Vol 74 (13) ◽  
pp. 4175-4184 ◽  
Author(s):  
Marie Kono ◽  
Ryuichi Koga ◽  
Masakazu Shimada ◽  
Takema Fukatsu
Keyword(s):  
Population Dynamics ◽  
Phylogenetic Analyses ◽  
Reproductive Activity ◽  
Adult Males ◽  
Female Development ◽  
Male Development ◽  
Infection Dynamics ◽  
Molecular Phylogenetic ◽  
Pseudococcus Comstocki

ABSTRACT We investigated the infection dynamics of endosymbiotic bacteria in the developmental course of the mealybugs Planococcus kraunhiae and Pseudococcus comstocki. Molecular phylogenetic analyses identified a betaproteobacterium and a gammaproteobacterium from each of the mealybug species. The former bacterium was related to the β-endosymbionts of other mealybugs, i.e., “Candidatus Tremblaya princeps,” and formed a compact clade in the Betaproteobacteria. Meanwhile, the latter bacterium was related to the γ-endosymbionts of other mealybugs but belonged to distinct clades in the Gammaproteobacteria. Whole-mount in situ hybridization confirmed the peculiar nested formation in the endosymbiotic system of the mealybugs: the β-endosymbiont cells were present in the cytoplasm of the bacteriocytes, and the γ-endosymbiont cells were located in the β-endosymbiont cells. In nymphal and female development, a large oval bacteriome consisting of a number of bacteriocytes was present in the abdomen, wherein the endosymbionts were harbored. In male development, strikingly, the bacteriome progressively degenerated in prepupae and pupae and became almost unrecognizable in adult males. In the degeneration process, the γ-endosymbionts disappeared more rapidly than the β-endosymbionts did. Quantitative PCR analyses revealed that (i) the population dynamics of the endosymbionts in female development reflected the reproductive activity of the insects, (ii) the population dynamics of the endosymbionts were strikingly different between female development and male development, (iii) the endosymbiont populations drastically decreased in male development, and (iv) the γ-endosymbiont populations decreased more rapidly than the β-endosymbiont populations in male development. Possible mechanisms underlying the uncoupled regulation of the β- and γ-endosymbiont populations are discussed in relation to the establishment and evolution of this unique prokaryote-prokaryote endosymbiotic system.

scholarly journals The metagenomics of biosilicification: causes and effects

2008 ◽  
Vol 72 (1) ◽  
pp. 221-225 ◽  
Author(s):  
L. G. Benning ◽  
D. J. Tobler
Keyword(s):  
Microbial Diversity ◽  
Bacterial Communities ◽  
Phylogenetic Diversity ◽  
Hot Springs ◽  
Phylogenetic Analyses ◽  
Geochemical Parameters ◽  
Molecular Phylogenetic ◽  
Geothermal Environments

AbstractIn order to determine the links between geochemical parameters controlling the formation of silica sinter in hot springs and their associated microbial diversity, a detailed characterisation of the waters and ofin situ-grown silica sinters was combined with molecular phylogenetic analyses of the bacterial communities in Icelandic geothermal environments. At all but one site, the microorganisms clearly affected, and in part controlled, the formation of the macroscopic textures and structures of silica sinter edifices. In addition, the class and genera level phylogenetic diversity and distribution appeared to be closely linked to variations in temperature, salinity and pH regimes.

Tripartite organization of the ancestral chordate brain and the antiquity of placodes: insights from ascidian Pax-2/5/8, Hox and Otx genes

Development ◽  
1998 ◽  
Vol 125 (6) ◽  
pp. 1113-1122 ◽  
Author(s):  
H. Wada ◽  
H. Saiga ◽  
N. Satoh ◽  
P.W. Holland
Keyword(s):  
Neural Tube ◽  
Hox Genes ◽  
Phylogenetic Analyses ◽  
Nervous Systems ◽  
Vertebrate Brain ◽  
Molecular Phylogenetic ◽  
Central Nervous Systems ◽  
Single Precursor ◽  
In Situ Hybridizations

Ascidians and vertebrates belong to the Phylum Chordata and both have dorsal tubular central nervous systems. The structure of the ascidian neural tube is extremely simple, containing less than 400 cells, among which less than 100 cells are neurons. Recent studies suggest that, despite its simple organization, the mechanisms patterning the ascidian neural tube are similar to those of the more complex vertebrate brain. Identification of homologous regions between vertebrate and ascidian nervous systems, however, remains to be resolved. Here we report the expression of HrPax-258 gene: an ascidian homologue of vertebrate Pax-2, Pax-5 and Pax-8 genes. Molecular phylogenetic analyses indicate that HrPax-258 is descendant from a single precursor gene that gave rise to the three vertebrate genes. The expression pattern of HrPax-258 suggests that this subfamily of Pax genes has conserved roles in regional specification of the brain. Comparison with expression of ascidian Otx (Hroth) and a Hox gene (HrHox1) by double-staining in situ hybridizations indicate that the ascidian brain region can be subdivided into three regions; the anterior region marked by Hroth probably homologous to the vertebrate forebrain and midbrain, the middle region marked by HrPax-258 probably homologous to the vertebrate anterior hindbrain (and maybe also midbrain) and the posterior region marked by Hox genes which is homologous to the vertebrate hindbrain and spinal cord. Later expression of HrPax-258 in atrial primordia implies that basal chordates such as ascidians have already acquired a sensory organ that develops from epidermal thickenings (placodes) and expresses HrPax-258; we suggest it is homologous to the vertebrate ear. Therefore, placodes are not likely to be a newly acquired feature in vertebrates, but may have already been possessed by the earliest chordates.

scholarly journals A new species of the Asian leaf litter toad genus Leptobrachella (Amphibia, Anura, Megophryidae) from southwest China

ZooKeys ◽  
2020 ◽  
Vol 943 ◽  
pp. 91-118 ◽  
Author(s):  
Shi-Ze Li ◽  
Jing Liu ◽  
Gang Wei ◽  
Bin Wang
Keyword(s):  
New Species ◽  
Leaf Litter ◽  
Phylogenetic Analyses ◽  
Small Body ◽  
The Body ◽  
Guizhou Province ◽  
Rrna Gene ◽  
Adult Males ◽  
Molecular Phylogenetic ◽  
A New Species

A new species of the Asian leaf litter toad genus Leptobrachella from Guizhou Province, China is described based on molecular phylogenetic analyses, morphological comparisons, and bioacoustics data. Phylogenetic analyses based on the mitochondrial 16S rRNA gene sequences supported the new species as an independent clade nested into the Leptobrachella clade and sister to L. bijie. The new species could be distinguished from its congeners by a combination of the following characters: small body size (SVL 30.8–33.4 mm in seven adult males, and 34.2 mm in one adult female); dorsal skin shagreened, some of the granules forming longitudinal short skin ridges; tympanum distinctly discernible, slightly concave; internasal distance longer than interorbital distance; supra-axillary, femoral, pectoral and ventrolateral glands distinctly visible; absence of webbing and lateral fringes on fingers; toes with rudimentary webbing and shallow lateral fringes, relative finger lengths II < IV < I < III; heels overlapped when thighs are positioned at right angles to the body; and tibia-tarsal articulation reaches the tympanum.

scholarly journals A new species of the Asian leaf litter toad genus Leptobrachella Smith, 1925 (Anura, Megophryidae) from northwest Guizhou Province, China

ZooKeys ◽  
2021 ◽  
Vol 1021 ◽  
pp. 81-107
Author(s):  
Yan-Lin Cheng ◽  
Sheng-Chao Shi ◽  
Jiaqi Li ◽  
Jing Liu ◽  
Shi-Ze Li ◽  
...  
Keyword(s):  
New Species ◽  
Leaf Litter ◽  
Phylogenetic Analyses ◽  
Morphological Characters ◽  
The Body ◽  
Guizhou Province ◽  
Adult Males ◽  
Dorsal Skin ◽  
Molecular Phylogenetic ◽  
A New Species

A new species of the Asian leaf litter toad genus Leptobrachella is described from Guizhou Province, China. Molecular phylogenetic analyses support the new species as an independent lineage deeply nested in the Leptobrachella clade. The new species is distinguished from its congeners by a combination of the following morphological characters: body size medium (SVL 29.7–31.2 mm in five adult males); dorsal skin shagreened, some of the granules forming longitudinal short skin ridges; tympanum distinctly discernible, slightly concave; supra-axillary, femoral, pectoral and ventrolateral glands distinctly visible; absence of webbing and lateral fringes on fingers; toes with narrow lateral fringes but without webbing; heels overlapping when thighs are positioned at right angles to the body; tibia-tarsal articulation reaching the middle of eye when leg stretched forward. The discovery highlighted the underestimated species diversity in the Leptobrachella toads in southwestern China.

scholarly journals A new species of the genus Rana sensu lato Linnaeus, 1758 (Anura, Ranidae) from Wuyi Mountain, Fujian Province, China

ZooKeys ◽  
2021 ◽  
Vol 1065 ◽  
pp. 101-124
Author(s):  
Yanqing Wu ◽  
Shengchao Shi ◽  
Huiguang Zhang ◽  
Weicai Chen ◽  
Bin Cai ◽  
...  
Keyword(s):  
New Species ◽  
Body Size ◽  
Phylogenetic Analyses ◽  
Dorsal Surface ◽  
Adult Males ◽  
Fujian Province ◽  
Closely Related Species ◽  
Adult Females ◽  
Molecular Phylogenetic ◽  
A New Species

A new species of the frog genus Rana sensu lato from Wuyi Mountain, Fujian Province, China is described. Molecular phylogenetic analyses clustered the new species into the R. johnsi group and indicated that it was genetically divergent from its closely related species. The new species could be distinguished from its congeners by a combination of the following characters: body size medium, SVL 41.4–45.6 mm (42.9 ± 1.9 mm, n = 4) in adult males and 47.6–50.3 mm (n = 2) in adult females; adult male with a pair of internal subgular vocal sacs; lateroventral grooves present on tip of toes; webbing on fourth toes reaching the tip of toe; transverse skin ridges distinctly present on the dorsal surface of thigh and tibia, the number large (mean 26.5 ± 2.7, range 22–29, n = 6); breeding males possess creamy white nuptial pad with tiny velvety spines on the dorsal surface of the first finger, divided into three parts.

scholarly journals Aerobic Biodegradation of Methyltert-Butyl Ether by Aquifer Bacteria from Leaking Underground Storage Tank Sites

2001 ◽  
Vol 67 (12) ◽  
pp. 5824-5829 ◽  
Author(s):  
S. R. Kane ◽  
H. R. Beller ◽  
T. C. Legler ◽  
C. J. Koester ◽  
H. C. Pinkart ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Butyl Alcohol ◽  
Water Soluble ◽  
Aerobic Biodegradation ◽  
Butyl Ether ◽  
Degrading Bacterium ◽  
In Situ Conditions ◽  
Molecular Phylogenetic ◽  
Mtbe Degradation

ABSTRACT The potential for aerobic methyl tert-butyl ether (MTBE) degradation was investigated with microcosms containing aquifer sediment and groundwater from four MTBE-contaminated sites characterized by oxygen-limited in situ conditions. MTBE depletion was observed for sediments from two sites (e.g., 4.5 mg/liter degraded in 15 days after a 4-day lag period), whereas no consumption of MTBE was observed for sediments from the other sites after 75 days. For sediments in which MTBE was consumed, 43 to 54% of added [U-14C]MTBE was mineralized to14CO2. Molecular phylogenetic analyses of these sediments indicated the enrichment of species closely related to a known MTBE-degrading bacterium, strain PM1. At only one site, the presence of water-soluble gasoline components significantly inhibited MTBE degradation and led to a more pronounced accumulation of the metabolite tert-butyl alcohol. Overall, these results suggest that the effects of oxygen and water-soluble gasoline components on in situ MTBE degradation will vary from site to site and that phylogenetic analysis may be a promising predictor of MTBE biodegradation potential.

Two Intracellular Symbiotic Bacteria from the Mulberry Psyllid Anomoneura mori (Insecta, Homoptera)

1998 ◽  
Vol 64 (10) ◽  
pp. 3599-3606 ◽  
Author(s):  
Takema Fukatsu ◽  
Naruo Nikoh
Keyword(s):  
In Situ Hybridization ◽  
16S Rdna ◽  
Phylogenetic Analyses ◽  
Symbiotic Bacteria ◽  
Polymorphism Analysis ◽  
16S Rdna Sequence ◽  
Rdna Sequences ◽  
16S Rdna Sequences ◽  
Molecular Phylogenetic

ABSTRACT We characterized the intracellular symbiotic bacteria of the mulberry psyllid Anomoneura mori by performing a molecular phylogenetic analysis combined with in situ hybridization. In its abdomen, the psyllid has a large, yellow, bilobed mycetome (or bacteriome) which consists of many round uninucleated mycetocytes (or bacteriocytes) enclosing syncytial tissue. The mycetocytes and syncytium harbor specific intracellular bacteria, the X-symbionts and Y-symbionts, respectively. Almost the entire length of the bacterial 16S ribosomal DNA (rDNA) was amplified and cloned from the whole DNA ofA. mori, and two clones, the A-type and B-type clones, were identified by restriction fragment length polymorphism analysis. In situ hybridization with specific oligonucleotide probes demonstrated that the A-type and B-type 16S rDNAs were derived from the X-symbionts and Y-symbionts, respectively. Molecular phylogenetic analyses of the 16S rDNA sequences showed that these symbionts belong to distinct lineages in the γ subdivision of the Proteobacteria. No 16S rDNA sequences in the databases were closely related to the 16S rDNA sequences of the X- and Y-symbionts. However, the sequences that were relatively closely related to them were the sequences of endosymbionts of other insects. The nucleotide compositions of the 16S rDNAs of the X- and Y-symbionts were highly AT biased, and the sequence of the X-symbiont was the most AT-rich bacterial 16S rDNA sequence reported so far.

A new species of the genus Megophrys (Amphibia: Anura: Megophryidae) from Hunan, China

Zootaxa ◽  
2019 ◽  
Vol 4695 (4) ◽  
pp. 301-330 ◽  
Author(s):  
LU WANG ◽  
XUEJIAN DENG ◽  
YONG LIU ◽  
QIANQIAN WU ◽  
ZHAO LIU
Keyword(s):  
New Species ◽  
Southern China ◽  
Phylogenetic Analyses ◽  
Small Body ◽  
Morphological Characters ◽  
Hunan Province ◽  
Rrna Gene ◽  
Adult Males ◽  
Molecular Phylogenetic ◽  
A New Species

We describe a new species of Megophryidae frog, Megophrys shunhuangensis sp. nov., from Hunan Province, Southern China. It can be distinguished from other known species in the subgenus Panophrys by morphological characters, bioacoustic data and a molecular divergence in the mitochondrial 16S rRNA gene similar to that found among other species of Panophrys. M. shunhuangensis sp. nov. is characterized by a relatively small body size, with adult females measuring 37.6 mm and adult males measuring 30.3–33.6 mm in snout to vent length; maxillary teeth present, vomerine teeth absent; tongue smooth, not notched behind; hindlimb slender, heels overlapping, tibio-tarsal articulation reaches forward between the nasal and tip of snout. Molecular phylogenetic analyses also show that M. sp. 6 from (Mao’er Shan, China) from Chen et al. (2017) and M. sp. 24 (Anjiangping and Mao’er Shan, China) from Liu et al. (2018) may be the same species as M. shunhuangensis sp. nov., we consequently speculate that the new species also distributed in Anjiangping and Mao’er Shan, China. At present, the genus Megophrys contains 85 species of which 48 species are distributed in China, and 30 belong to the subgenus Panophrys. 

scholarly journals Symbiotic Bacteria Associated with Stomach Discs of Human Lice

2006 ◽  
Vol 72 (11) ◽  
pp. 7349-7352 ◽  
Author(s):  
Kayoko Sasaki-Fukatsu ◽  
Ryuichi Koga ◽  
Naruo Nikoh ◽  
Kazunori Yoshizawa ◽  
Shinji Kasai ◽  
...  
Keyword(s):  
Ventral Side ◽  
Nucleotide Composition ◽  
Posterior Pole ◽  
Symbiotic Bacteria ◽  
Rrna Gene ◽  
Adult Males ◽  
Large Aggregate ◽  
Molecular Phylogenetic ◽  
Female Specific

ABSTRACT The symbiotic bacteria associated with the stomach disc, a large aggregate of bacteriocytes on the ventral side of the midgut, of human body and head lice were characterized. Molecular phylogenetic analysis of 16S rRNA gene sequences showed that the symbionts formed a distinct and well-defined clade in the Gammaproteobacteria. The sequences exhibited AT-biased nucleotide composition and accelerated molecular evolution. In situ hybridization revealed that in nymphs and adult males, the symbiont was localized in the stomach disc, while in adult females, the symbiont was not in the stomach disc but in the lateral oviducts and the posterior pole of the oocytes due to female-specific symbiont migration. We propose the designation “Candidatus Riesia pediculicola” for the louse symbionts.

scholarly journals Rodent host population dynamics drive zoonotic Lyme Borreliosis and Orthohantavirus infections in humans in Northern Europe

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mahdi Aminikhah ◽  
Jukka T. Forsman ◽  
Esa Koskela ◽  
Tapio Mappes ◽  
Jussi Sane ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Lyme Borreliosis ◽  
Bank Vole ◽  
Myodes Glareolus ◽  
Northern Europe ◽  
Time Lags ◽  
Rodent Population ◽  
Vole Cycles ◽  
Infection Dynamics ◽  
Abundance Fluctuations

AbstractZoonotic diseases, caused by pathogens transmitted between other vertebrate animals and humans, pose a major risk to human health. Rodents are important reservoir hosts for many zoonotic pathogens, and rodent population dynamics affect the infection dynamics of rodent-borne diseases, such as diseases caused by hantaviruses. However, the role of rodent population dynamics in determining the infection dynamics of rodent-associated tick-borne diseases, such as Lyme borreliosis (LB), caused by Borrelia burgdorferi sensu lato bacteria, have gained limited attention in Northern Europe, despite the multiannual abundance fluctuations, the so-called vole cycles, that characterise rodent population dynamics in the region. Here, we quantify the associations between rodent abundance and LB human cases and Puumala Orthohantavirus (PUUV) infections by using two time series (25-year and 9-year) in Finland. Both bank vole (Myodes glareolus) abundance as well as LB and PUUV infection incidence in humans showed approximately 3-year cycles. Without vector transmitted PUUV infections followed the bank vole host abundance fluctuations with two-month time lag, whereas tick-transmitted LB was associated with bank vole abundance ca. 12 and 24 months earlier. However, the strength of association between LB incidence and bank vole abundance ca. 12 months before varied over the study years. This study highlights that the human risk to acquire rodent-borne pathogens, as well as rodent-associated tick-borne pathogens is associated with the vole cycles in Northern Fennoscandia, yet with complex time lags.

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