18 Matching Annotations
  1. Jun 2019
    1. with the plunger of a Hamilton syringe. The tube was centrifuged at room temperature at 14,000 rpm for 30 min. The above process of gel-disruption and centrifugation was repeated twice subsequent to which the oil layer was aspirated and suitable aliquots from the supernatant were taken for estimation of Csat by Drabkin' s reagent (Goldberg eta!, 1977).
    2. he gelation concentrations of HbS constructs were determined by the dextran-Csat method of Bookchin et a! (Bookchin et a!, 1999). This method allows measurement of Csat under near-physiological conditions and at much lower concentration of HbS (about 5-fold or less) than that required in standard Csat assays, but essentially provides the same information. Briefly, a suitable aliquot of a concentrated solution of hemoglobin in potassium phosphate buffer (0.05 M, pH 7.50) was taken in a 1.5 ml micro-centrifuge tube. A concentrated dextran (70 kDa) solution prepared in the same buffer was added to it and mixed well. This mixture was overlaid with 0.5 ml of mineral oil, chilled on ice bath and deoxygenated with an anaerobically prepared dithionite solution through an airtight Hamilton syringe. The final concentrations of dextran and dithionite in the mixture were 120 mg/ml and 0.05 M respectively. The deoxygenated sample above was allowed to polymerize at 37°C for 30 min after which the gel under the oil layer was disrupted
  2. May 2019
    1. For clonogenic assays, 1x103 (A549) or 2x103 (E-10) cells were seeded per well of a six well tissue culture plate and grown for 15 days. For identification of signaling pathways various inhibitors were used viz, PI3K inhibitor LY294002 (10μM), MEK inhibitor PD98059 (10μM) or p38 inhibitor SB203580 (10μM). Cells were grown in the presence of inhibitor for seven days following which fresh medium was added. For staining, cells were washed twice with PBS and fixed in 10% formalin for 10 minutes, washed extensively with water and stained with 0.25% crystal violet prepared in 25% methanol for 4hrs at 4°C. Plates were then washed with milli Q water and dried before scanning
    1. the membrane and sandwiched between 1 piece of buffer-soaked Whatman paper from Biorad on each side. The sandwich was placed between graphite electrodes with the membrane towards the anode. The transfer was done for 12-16 hr using a voltage of 40 V in the cold room. Protein transfer was viwed using Ponceau S staining. Blot was dipped in the Ponceau S stain under shaking and washed using PBST. After transfer, the membrane was blocked with 5% non-fat milk in PBST (1X PBS with 0.1% Tween-20) for 2 hr at room temperature. The membrane was then washed thrice with PBST under shaking and incubated with the primary antibody (1:1000 dilution in PBST) for 12-16 hr. The membrane was again washed thrice under shaking with PBST and incubated with 1:20000 dilution alkaline phosphatase conjugated anti-goat IgG secondary antibody (in PBST) for 2 hr. The membrane was once again washed thrice as described above and the signal developed using ECL kit from Amersham on X-ray films in a dark room. The reactive protein bands appeared as black bands upon gentle shaking at room temperature in 1X developer solution. The reaction was stopped by dipping and shaking the film in 1X Fixer solution followed by washing in water
    2. The protein samples separated on SDS-PAGE were transferred to PVDF (polyvinyledene difluoride) membrane (Amersham, Buckinghamshire, UK) electrophoretically by a semi-dry method using BioRad apparatus. The gel and the membrane (pre-wetted with methanol) were wetted with transfer and the gel was placed in contact with
    3. Obtaining transpositions near a gene of interest was achieved in a two-step procedure. The population (pool) of cells carrying random transpositions (described in the previous Section) at different places on the chromosome was used to prepare a P1 phage lysate. This lysate was then used to infect a suitable recipient strain and transductants were sought in a simultaneous (double) selection for two markers, namely the antibiotic marker on the mini-transposon and selection for the phenotype of the gene or mutation which was intended to be linked with the antibiotic marker. The transductants so isolated were purified and further P1 phage preparations were made on these individual clones. By retransducing with these lysates into the same recipient cells and observing the segregation of phenotypes after selection for the transposon marker, the cotransduction values were obtained between the transposon insertion and the gene (or mutation) of interest
    1. Quantitative measurement of periplasmic acid phosphatase activity in phosphate-starved C. glabratacells was performedas mentioned previously (Orkwis et al., 2010). A total of 0.5 OD600YNB-grown and phosphate-starved cells were collected, washed thrice with cold water and oncewith cold 0.1 M sodium acetatebuffer (pH 4.2). Washed cells were resuspendedin 500 μl sodium acetate (0.1 M)and incubated at 30 ̊C with constant stirring. After 10 min incubation, 500 μl freshly-prepared solution of 20 mM p-nitrophenyl phosphate in 0.1 M sodium acetate(pH 4.2) was added to the cell suspension. Enzymatic activity was stopped after incubation at 25 ̊C for 20 min by addition of 250 μl sodium carbonate (1 M)tothe reaction mix. Resultant colour change was measured by monitoring absorbance at 400 nm. Acid phosphatase activity was expressed as a ratio of OD400to OD600 to normalize against cell density
    2. Determination of acid phosphatase activity
    1. C. glabratacells grown either in RPMI medium or harvested from THP-1 macrophages were collected, washed with DEPC treated water and were disrupted with glass beads in trizol. Total RNA was isolated using acid phenol extraction method and frozen at -80C. Quality of RNA was examined by determiningtheRNAintegrity number (RIN) before microarrayanalysis.Microarray experiments wereperformed atOcimum Biosolutions Ltd., Hyderabad (http://www.ocimumbio.com). Briefly, a4x44K GE Agilent array comprised of 10,408 probes representing 5,205 ORFs of C. glabratawas used wherein average number of replicates for each probe was four to five. Feature Extraction software version (Agilent) and Quantile normalization was used for data analysis. Hierarchical clustering was performed using Complete Linkage methodwith Euclidean Distance as distance measure. Data arethe average of two hybridizations from biological replicates ofeach sample and raw data sets for this study areavailable at the Gene Expression Omnibus database(Accession number -GSE38953)
    2. E. coliDH5α strain was transformed with plasmids carrying appropriate inserts to clone and generatedeletion strains of C. glabrataORFs(Sambrook, 2001). Ultracompetentcells stored at -70⁰C were thawed on icefor 5-10 min. 5 μlligated plasmid was added to100 μlultracompetent cells andcells were incubatedon ice. After 30 min, competent cells were subjected to heat shock at 42⁰C for 90 seconds. Cells were immediately transferredtoicefor 2-3min. Next, 800 μlSOC (or LB) medium was added and cells were allowed to recover for 45 minon a shaker incubator set at 37⁰C.After the recovery, cells were centrifuged at 2,500g for 4 min. Medium supernatant was discarded and cells were resuspended in 200 μlfresh sterile LBmedium. Cells were plated on LB agar medium containing appropriate antibiotics. Plates wereincubatedat37⁰C for 12-16 h
    1. Uniquitination assay was performed as described by Choo and Zhang, 2009. Ubiquitination is an enzymatic process of the covalent attachment of polypeptide ubiquitin on specific lysine residuesof protein, which is thendegraded by proteasome complex. MG132 (carbobenzoxy-Leu-Leu-Leucinal), a proteolytic activity inhibitor of proteasome complex, is widely used to assess the stability of protein in vivo. Briefly, parental and profilin-stable cells were treated with 10 μM MG132 for 6 h. The whole cell extracts prepared in NTEN lysis buffer were then subjected to immunoprecipitation with anti-ubiquitin antibody. The analysis of ubiquitination was performed by immunoblotting with anti-PTEN antibody
    1. Cellswere grown in YPD to an OD600of 0.5-0.7. Cells equivalent to 1OD600were washed with synthetic complete medium without uacil twice and suspended in SC-Ura containing 3 μCi/mLof [14C]uracil for 5 min. Cells were pelleted and washed with SC-Ura medium twice and suspended in 0.5 mLof AE solution(Section 1OD600of this cell suspension was counted in a liquid scintillation counter (Perkin Elmer-Tricarb 2900). The cpm values obtained were and converted into moles based on thespecific activity of [14C] uracil and plotted using GraphPad Prism5
    1. Cells were grown overnight on coverslips and transfected with various combinations of plasmids. Post 24 hrs. of transfection, cells were washed with PBS and then fixed in 3% w/v paraformaldehyde in 1X PBS containing 50 mM sucrose for 15 minutes at room temperature. Cells were permeabilized with permeabilization buffer i.e. 0.5% Triton X-100 buffer containing20mM HEPES at pH 7.4, 50mM NaCl, 3mM MgCl2 and 300mM sucrose and were incubated for 5 min.at room temperature.Cells were washed twice with 1X PBS and blocked with 3% BSA/PBS for 30 minutes. Cells were incubated with specificprimary antibody diluted in the blocking buffer. After 2 hours of incubation, cells were washed thrice with 1X PBS (each washfor 5 minutes). The 1X PBS was removed,and the cellswere incubatedwith specific FITC or Rhodamine-conjugated secondary antibodyat 37°C for 30 min.To visualize nuclei, cells were co-stained with DAPI (10 μg/ml). Cellswere washed thrice with 1X PBS and after final wash, coverslips containing cell weremounted on the slidesusing glycerine containing paraphenylenediamine. The cells were analyzed using confocal microscopy facility at CDFD
    1. CFUs/ml) onto fully expanded leaf, and pricking with sterile needle to facilitate the entry of bacteria inside the leaves through wound. To detrmine the growth of bacteria inside leaves, 1 cm2 leaf area surrounding the inoculation site was cut at regular time intervals, surface sterilized by dipping in 2% (vol/vol) sodium hypochlorite for 2 min, and washed twice in sterile water. For getting the CFUs, leaves were crushed using mortar and pestle, serially diluted, and plated on PSA medium containing appropriate antibiotics
    2. Exogenous iron supplementation was performed as described previously (Chatterjee and Sonti, 2002). Briefly, leaves of 40-day-old greenhouse-grown rice plants of the susceptible rice cultivar Taichung Native-1 (TN-1) were cut with scissors 2 cm above the junction of the leaf blade and leaf sheath. These cut leaves (25 leaves per flasks) were dipped in 250 ml conical flasks containing 200 ml 1μg/mlof Benzyl amino purine (BAP) in double distilled water. BAP (a cytokine hormone) maintain the detached rice leaves in fresh condition for longer period. For iron supplementation, FeCl3 was added to a final concentration of 50 μM (stock-10 mM). Prior to inoculation with different strains of Xanthomonas oryzaepv. oryzicola, the leaves were maintained overnight on a laboartory bench top. Strains were inoculated into the leaves by needle pricking method by dropping 20μl of bacterial suspension (approx. 1 × 108bacterial
    1. using the GENESPRING GX (Version 12.0) software,normalized to 75 percentile shift and represent the average of two hybridizations from biological replicates for each sample. Functional annotation of differentially regulated gene set(≥1.5 Fold change with p≤0.05)was performed using the GENESPRING GX (Version 12.0) softwareand GO terms with p<0.05 were considered as statistically significant. Using the REVIGO tool(http://revigo.irb.hr), redundant and significantly overlapping GO terms were removed and summarized. In REVIGO analysis, S. cerevisiaedatabase was chosen for GOterm sizes andtheallowed similarity value was set to 0.5(small).Additionally, to identify the overlap among differentially expressed genes, functional category analysis was performed usingthefungal specific annotation tool FUNGIFUN (https://sbi.hki-jena.de/FungiFun/FungiFun.cgi). Significantly enriched FunCat (Functional Catalogue) associated pathways were extracted usingthewhole C. glabratagenome as background and compared across differentially regulated gene sets. The parameters used for FUNGIFUN analysis were cut-off p=0.05; Fisher’s exact test; FunCatlevel 3. Raw data sets for this study are available attheGene Expression Omnibus database (http://www.ncbi.nlm. nih.gov/geo; accession no. GSE60741
    2. Log-phase C. glabratacells were grown either in YNB or YNB medium supplemented witheither50 μMBPS(iron limiting) or 500 μMferric chloride (iron excess) for 2 h. Cells were spun down at 4,000 rpm for 5 min and washed twice with ice-cold DEPC-treated water. Total RNA was extracted usingtheacid phenolisolationmethod, resuspended in nuclease-free water and stored at -80°C. The frozen RNA samples were sent to Genotypic Technology Ltd., Bangalore (http://www.genotypic.co.in) wherein quality of RNA samples wasdetermined by examining the RNA integrity number (RIN) before performing microarray analysis. Next, the 8x15 GE Agilent array,comprised of 60mer oligonucleotides representing a total of 5,503 C. glabrataORFs (three replicates of each probe on average),was used for single colour microarray experiments.Datawereextracted
    1. Cell adhesion assayswereperformed as described previously (Hockinget al., 1998)withslight modifications. Fibronectin coating was done overnight at 4°C. 5×104 cells were seeded per well onto fibronectin (2 μg/mL) coated 24 well platesin triplicates. Cells were allowed to adhere for different time periods. At each time point, unadhered cells were washed away with PBS; adhered cells were trypsinized and counted with a hemocytometer. Percentage of adhesion was calculated by normalizing total number of adhered cells at each time point to number of cells adhered after 5 h