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81.
Many arthropods with restricted diets rely on symbiotic associations for full nutrition and fecundity. Tsetse flies (Diptera:
Glossinidae) harbor three symbiotic organisms in addition to the parasitic African trypanosomes they transmit. Two of these microorganisms
reside in different gut cells, while the third organism is harbored in reproductive tissues and belongs to the genus Wolbachia. The primary symbiont (genus Wigglesworthia glossinidia) lives in differentiated epithelial cells (bacteriocytes) which form an organ (bacteriome) in the anterior gut, while the
secondary (S) symbionts are present in midgut cells. Here we have characterized the phylogeny of Wigglesworthia based on their 16S rDNA sequence analysis from eight species representing the three subgenera of Glossina: Austenina (=fusca group), Nemorhina (=palpalis group), and Glossina (=morsitans group). Independently, the ribosomal DNA internal transcribed spacer-2 (ITS-2) regions from these species were analyzed.
The analysis of Wigglesworthia indicated that they form a distinct lineage in the γ subdivision of Proteobacteria and display concordance with their host
insect species. The trees generated by parsimony confirmed the monophyletic taxonomic placement of Glossina, where fusca group species formed the deepest branch followed by morsitans and palpalis groups, respectively. The placement of the species Glossina austeni by both the traditional morphological and biochemical criteria has been controversial. Results presented here, based on both
the ITS-2 and the symbiont 16S rDNA sequence analysis, suggest that Glossina austeni should be placed into a separate fourth subgenus, Machadomyia, which forms a sister-group relationship with the morsitans group species.
Received: 17 March 1998 / Accepted: 1 May 1998 相似文献
82.
Kosar F Sahin I Acikgöz N Aksoy Y Kucukbay Z Cehreli S 《Biological trace element research》2005,107(1):1-10
It is known that certain trace elements can affect various heart diseases. In this study, we aimed to evaluate the changes in concentrations of certain serum trace elements in patients with chronic rheumatic heart disease (RHD). Serum analysis of selenium (Se), zinc (Zn), and copper (Cu) trace elements was assayed by atomic absorption spectrophotometry. RHD patients had significantly lower serum concentrations of Se and Zn than control subjects (p < 0.05 and p < 0.001, respectively). However, the serum Cu concentration was significantly higher in RHD patients than in controls (1.93 +/- 0.59 microg/L vs 1.06 +/- 0.29 microg/L; p < 0.001). Similarly, the Cu/Zn ratio in RHD patients was higher than in control subjects (4.70 +/- 0.92 vs 1.68 +/- 0.45; p < 0.001). Additionally, no significant correlation was found among these trace element concentrations and the functional capacity classes (p > 0.05). RHD patients had decreased serum Se and Zn element concentrations and increased serum Cu element concentration. We suggest that Se and Zn deficiency might be contributory factors in the development of rheumatic heart disease, and a high Cu concentration and a high Cu/Zn ratio might reflect an ongoing inflammatory process in this disease. 相似文献
83.
Influence of Precursor Availability on Alkaloid Accumulation by
Transgenic Cell Line of Catharanthus roseus 总被引:7,自引:0,他引:7 下载免费PDF全文
Serap Whitmer Camilo Canel Didier Hallard Cecilia Gon?alves Robert Verpoorte 《Plant physiology》1998,116(2):853-857
We have used a transgenic cell line of Catharanthus roseus (L.) G. Don to study the relative importance of the supply of biosynthetic precursors for the synthesis of terpenoid indole alkaloids. Line S10 carries a recombinant, constitutively overexpressed version of the endogenous strictosidine synthase (Str) gene. Various concentrations and combinations of the substrate tryptamine and of loganin, the immediate precursor of secologanin, were added to suspension cultures of S10. Our results indicate that high rates of tryptamine synthesis can take place under conditions of low tryptophan decarboxylase activity, and that high rates of strictosidine synthesis are possible in the presence of a small tryptamine pool. It appears that the utilization of tryptamine for alkaloid biosynthesis enhances metabolic flux through the indole pathway. However, a deficiency in the supply of either the iridoid or the indole precursor can limit flux through the step catalyzed by strictosidine synthase. Precursor utilization for the synthesis of strictosidine depends on the availability of the cosubstrate; the relative abundance of these precursors is a cell-line-specific trait that reflects the metabolic status of the cultures. 相似文献
84.
Fatih Mehmet Simsek Celal Ulger Mustafa Muhammed Akiner Serap Senol Tuncay Ferhat Kiremit Fevzi Bardakci 《Biochemical Systematics and Ecology》2011,39(4-6):258-265
The present study was set to identify the members of An. maculipennis complex, which includes effective malaria vectors, throughout the Mediterranean region of Turkey using the second internal transcribed spacer of ribosomal DNA (rDNA-ITS2) sequences from 200 specimens. Resulting sequences of this complex from the Mediterranean region revealed the presence of three species belonging to the An. maculipennis complex, namely An. sacharovi, An. maculipennis s.s. and An. melanoon. The lengths of ITS2 region were 284, 294 and 306 bp in length for An. maculipennis s.s., An. melanoon and An. sacharovi respectively. While no sequence divergence was observed within any species, An. sacharovi was the most distantly related species from An. maculipennis s.s. and An. melanoon with a sequence divergence of 15.1% and 15.4%, respectively. While An. melanoon was the rare species, An. maculipennis s.s., was the most abundant and An. sacharovi was the most wide spread one. 相似文献
85.
86.
Mine Aksoy M. Serhat Ozaslan 《Journal of enzyme inhibition and medicinal chemistry》2016,31(4):546-550
Glutathione S-transferases (GSTs) are an important enzyme family which play a critical role in detoxification system. In our study, GST was purified from muscle tissue of Chalcalburnus tarichii Pallas with 301.5-fold purification and 19.07% recovery by glutathione agarose affinity chromatography. The purity of enzyme was checked by sodium dodecyl sulfate–polyacrylamide gel electrophoresis, showing a two band, because of having heterodimer structure. KM values were 1.59 and 0.53?mM for 1-chloro-2,4-dinitrobenzene (CDNB) and glutathione (GSH), respectively. Vmax values for CDNB and GSH were also determined as 5.58 and 1.88?EU/mL, respectively. In addition, inhibition effects of Ag+, Cu2+, Cd2+, Fe3+, Pb2+, Cr2+, Co2+ and Zn2+ metal ions were investigated on the enzyme activity and IC50, Ki values were calculated for these metal ions. 相似文献
87.
Öztürk Gökçe Zahide Neslihan Aksoy Emre Bakhsh Allah Demirel Ufuk Çalışkan Sevgi Çalışkan Mehmet Emin 《Functional & integrative genomics》2021,21(3-4):489-502
Functional & Integrative Genomics - MicroRNAs are small, non-coding RNAs that are responsible for regulation of gene expression during plant growth and development. Although there are many... 相似文献
88.
89.
Opposing Effects of CREBBP Mutations Govern the Phenotype of Rubinstein-Taybi Syndrome and Adult SHH Medulloblastoma 总被引:1,自引:0,他引:1
Daniel J. Merk Jasmin Ohli Natalie D. Merk Venu Thatikonda Sorana Morrissy Melanie Schoof Susanne N. Schmid Luke Harrison Severin Filser Julia Ahlfeld Serap Erkek Kaamini Raithatha Thomas Andreska Marc Weißhaar Michael Launspach Julia E. Neumann Mehdi Shakarami Dennis Plenker Ulrich Schüller 《Developmental cell》2018,44(6):709-724.e6
90.
Meliha Sengezer Inceli Engin Kaptan Serap Sancar Osman Murathanoglu Songul Suren Castillo 《Biologia》2010,65(1):157-163
The dorsal and ventral skin in amphibians plays an important role in osmoregulation. Prolactin hormone is involved in regulation
of amphibian skin functions, such as water and electrolyte balance. Therefore, amphibians may be useful as a model for determining
the sites of the prolactin receptor. In this study, prolactin receptor was detected in frog dorsal and ventral skin using
immunohistochemical staining method. Prolactin receptor immunoreactivity was localized in all epidermal layers except stratum
corneum of dorsal skin epidermis, stratum germinativum layer of ventral skin epidermis, myoepithelial cells, secretory epithelium
and secretory channel cells of granular glands in both skin regions. The mucous glands and secretory granules of granular
glands did not show immunoreactivity for the prolactin receptor. According to our immunohistochemical results, the more widespread
detection of prolactin receptor in dorsal skin epidermis indicates that prolactin is more effective in dorsal skin. Presence
of prolactin receptors in epidermis points out its possible osmoregulatory effect. Moreover, detection of receptor immunoreactivity
in various elements of poison glands in the dermis of both dorsal and ventral skin regions suggests that prolactin has a regulatory
effect in gland functions. 相似文献