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1.
Using a biolistic device built here and based on the principle of the device described by Klein et al. (1987). we have reproducibly obtained transformants of Chlamydomonas reinhardtii . The reproducibility of the method has allowed us to examine the maintenance and expression of cloned DNA fragments introduced into C. Reinhardtii .  相似文献   
2.
Group-wise diversity of sediment methylotrophs of Chilika lake (Lat. 19°28′–19°54′N; Long. 85°06′–85°35′E) Odisha, India at various identified sites was studied. Both the culturable and unculturable (metagenome) methylotrophs were investigated in the lake sediments employing both mxaF and 16S rRNA genes as markers. ARDRA profiling, 16S rRNA gene sequencing, PAGE profiling of HaeIII, EcoRI restricted mxaF gene and the mxaF gene sequences using culture-dependent approach revealed the relatedness of α-proteobacteria and Methylobacterium, Hyphomicrobium and Ancyclobacter sp. The total viable counts of the culturable aerobic methylotrophs were relatively higher in sediments near the sea mouth (S3; Panaspada), also demonstrated relatively high salinity (0.1 M NaCl) tolerance. Metagenomic DNA from the sediments, amplified using GC clamp mxaF primers and resolved through DGGE, revealed the diversity within the unculturable methylotrophic bacterium Methylobacterium organophilum, Ancyclobacter aquaticus, Burkholderiales and Hyphomicrobium sp. Culture-independent analyses revealed that up to 90 % of the methylotrophs were unculturable. The study enhances the general understandings of the metagenomic methylotrophs from such a special ecological niche.

Electronic supplementary material

The online version of this article (doi:10.1007/s12088-015-0510-3) contains supplementary material, which is available to authorized users.  相似文献   
3.
Iodide is actively concentrated in the thyroid gland for thyroid hormone biosynthesis. Excess iodine has been observed to induce apoptosis in thyrocytes and mammary cells. The mechanism of iodine induced apoptosis is poorly understood. Among various cell organelles, mitochondria is known to provide conducive environment for the organification of iodine, i.e. iodination of different proteins. Mitochondria also play a central role in execution of apoptosis. To study the role of mitochondria in iodine induced apoptosis, we investigated the direct interaction of iodine and human breast mitochondria vis-a-vis its role in the initiation of apoptosis in vitro. We observed that mitochondria isolated from the tumor (TT) and extra-tumoral tissue (ET) of human breast display significant uptake of iodine. Mitochondrial proteins were observed to be predominantly iodinated in ET but not in TT mitochondria. Treatment with iodine showed an increase in mitochondrial permeability transition of TT and decrease in ET. Iodine induced released factor(s) other than cytochrome c from tumor mitochondria initiate(s) apoptosis in vitro, while those from ET mitochondria were non-apoptogenic in nature. To our knowledge, this is first report demonstrating that iodine acts differentially on mitochondria of tumor and extratumoral origin to release apoptogenic proteins from TT and has a protective effect on ET.  相似文献   
4.
    
A study was conducted to identify common arbuscular mycorrhizal (AM) fungi present in rhizosphere of Jatropha curcas L., an important bio-diesel crop, from different arid and semi arid regions of India viz., Jodhpur (Rajasthan), Hissar (Haryana), Jhansi and Lalitpur (Uttar Pradesh) and Hyderabad (Andhra Pradesh). A total of 20 AM species were recorded, which consisted of two species of Acaulospora and 18 species of Glomus. The highest frequency of occurrence was recorded for Glomus intraradix (100%), followed by Acaulospora scrobiculata (83%), G. etunicatum (50%) and Glomus 1 (50%). Maximum species richness was recorded at Jodhpur, followed by Jhansi, Hissar, Hyderabad and Lalitpur. The results seem to suggest that species richness was more in arid regions as compared to semi arid areas.  相似文献   
5.
We have previously established mouse genetic models and identified the genetic components of quantitative trait loci (QTL) on mouse chromosomes that contribute to phenotypes such as bone size, bone density, and bone's anabolic response to mechanical loading. However, these regions contain dozens of unknown genes that are needed for functional testing. In this study, we provided a protocol of nucleoporation with high efficiency by using a commercial nucleofection buffer and Gene Pulser to deliver a test gene into bone cells for functional studies. We cloned an osteoblast differentiation-specific geneosterix (Osx) from a mouse bone cDNA library into a pHGCX expression vector and used nucleoporation to deliver pHGCX/Flag-Osx into the nuclei of MC3T3-E1 cells. We then examined the transfection efficiency transgene expression, and function. Our results have demonstrated that nucleoporation can deliver a transgene into MC3T3-E1 osteoblast cells with approx 94% transfection efficiency, and express a functional Flag-Osx fusion protein capable of inducing cell differentiation as measured by an incease in alkaline phosphatase (ALP) activity. Therefore, this experimental system provides a rapid, safe, and efficient cell-based model of high-throughput phenotypic screening to identify candidate genes from physically mapped regions that are important for osteoblast differentiation.  相似文献   
6.
The effect of methanol extract of whole plants of Trichodesma indicum R. Br. has been investigated on sulphur dioxide (SO2) induced cough reflex in Swiss albino mice. The extract has demonstrated significant (p < 0.001) inhibition in frequency of cough in all the tested doses when compared with untreated control group. The effect persisted up to 90 min of its oral administration and also comparable to that of the effect exhibited by the standard drug (Codeine phosphate). This study confirmed the traditional use of this plant in the treatment of cough. Determination of underlying mechanism of beneficial effect is major topic requiring further comprehensive investigation.  相似文献   
7.
Eosinophilic esophagitis (EoE) is an emerging chronic esophageal disease. Despite the increasing diagnosis of EoE globally, the causes of EoE and other esophageal eosinophilic disorders are not clearly understood. EoE pathology includes accumulation of inflammatory cells (e.g., eosinophils, mast cells), characteristic endoscopic features (e.g., furrows, the formation of fine concentric mucosal rings, exudates), and functional impairments (e.g., esophageal stricture, dysmotility). We hypothesized that the esophageal structural pathology and functional impairments of EoE develop as a consequence of the effector functions of the accumulated inflammatory cells. We analyzed eosinophils (anti-major basic protein immunostaining), esophageal stricture (X-ray barium swallowing), and esophageal motility (isometric force) in two established transgenic murine models of EoE (CD2-IL-5 and rtTA-CC10-IL-13) and a novel eosinophil-deficient model (ΔdblGATA/CD2-IL-5). Herein, we show the following: 1) CD2-IL-5 and doxycycline (DOX)-induced rtTA-CC10-IL-13 mice have chronic eosinophilic and mast cell esophageal inflammation; 2) eosinophilic esophageal inflammation promotes esophageal stricture in both transgenic murine models; 3) the eosinophil-deficient ΔdblGATA/CD-2-IL-5 mice were protected from the induction of stricture, whereas the eosinophil-competent CD2-IL-5 mice develop esophageal stricture; 4) esophageal stricture is not reversible in DOX-induced rtTA-CC10-IL-13 mice (8 wk DOX followed by 8 wk no-DOX); and 5) IL-5 transgene-induced (CD2-IL-5) EoE evidences esophageal dysmotility (relaxation and contraction) that is independent of the eosinophilic esophageal inflammation: CD2-IL-5 and ΔdblGATA/CD2-IL-5 mice have comparable esophageal dysmotility. Collectively, our present study directly implicates chronic eosinophilic inflammation in the development of the esophageal structural impairments of experimental EoE.  相似文献   
8.
9.
The mesophilic strains Aspergillus flavus CFR 10 and Fusarium oxysporum CFR 8 are potent producers of extracellular thermoactive chitinases (endo-chitinase and β-N-acetylhexosaminidase). Chitinases have a wide range of applications in many areas including reclamation of seafood processing chitinous by-products. In the present study, the interactive effects of four fermentation conditions on thermoactive chitinase production by solid state fermentation (SSF) using commercial wheat bran (CWB) was investigated employing response surface methodology (RSM). Further, these chitinases were applied for the preparation of N-acetyl chitooligosaccharides from shrimp chitin. Statistical optimization resulted in the production (unit/g initial dry substrate, U/g IDS) of 19.8 endo-chitinase and 649.0 β-N-acetylhexosaminidase activity by A. flavus CFR 10, and 17.5 endo-chitinase and 319.9 β-N-acetylhexosaminidase activity by F. oxysporum CFR 8. Activity of crude endo-chitinase and β-N-acetylhexosaminidase were found to be optimum at 62?±?1 °C in a wide pH range. Hydrolysis of colloidal chitin with crude chitinases produced the maximum N-acetyl chitooligosaccharides yield (mmol/l) of 10.4?±?0.28 at 6 h and 10.2?±?0.01 at 30 h post-reaction initiation, respectively, by the enzymes of A. flavus CFR 10 and F. oxysporum CFR 8. HPLC analysis revealed the presence of N-acetyl chitooligosaccharides with N-acetyl chitotriose as the main end product of the colloidal chitin hydrolysis. These results indicate the potential of mesophilic A. flavus CFR 10 and F. oxysporum CFR 8 in the production of thermoactive chitinases employing the economical SSF process using CWB as an ideal substrate, as well as the potential of these chitinases for the reclamation of abundant shrimp processing by-products and production of defined N-acetyl chitooligosaccharides.  相似文献   
10.
Procedure for the Agrobacterium tumefaciens mediated T-DNA delivery into the elite clone(s) of Eucalyptus tereticornis using leaf explants from microshoots has been developed. Amongst two strains of A. tumefaciens namely, EHA105 and LBA4404 (harbouring pBI121 plasmid), strain EHA105 was found to be more efficient. Pre-culturing of tissue (2 days) on medium supplemented with 100 μM acetosyringone, before bacterial infection significantly increased transient expression of reporter gene (GUS). Co-cultivation period of 2 days and a bacterial density of 0.8 OD600 resulted in higher transient GUS expression. Method of injury to tissue, presence of acetosyringone in co-cultivation medium and photoperiod during co-cultivation also influenced the expression of transient GUS activity. Amongst the three clones tested, maximum transient GUS activity was recorded in clone ‘CE2’ followed by clone ‘T1’. Regeneration of transformed shoots was achieved on modified Murashige and Skoog medium (potassium nitrate was replaced with 990 mg/l potassium sulphate and ammonium nitrate with 392 mg/l ammonium sulphate, and mesoinositol concentration was increased to 200 mg/l). Stable transformation was confirmed on the basis of GUS activity and PCR amplification of DNA fragments specific to uidA and nptII genes. The absence of bacteria in the stable transformed tissues was confirmed by PCR amplification of fragment specific to 16S rRNA of bacteria.  相似文献   
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