Identification of complex III, NQR and SDH as pharmacologic targets in non-multiplying Pseudomonas aeruginosa cultured in urine-like conditions
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Q Exactive HF
ORGANISM(S): Pseudomonas Aeruginosa Pao1 (ncbitaxon:208964)
SUBMITTER: 
Oscar Juarez
PROVIDER: MSV000093610 | MassIVE | Fri Dec 08 11:09:00 GMT 2023
SECONDARY ACCESSION(S): PXD047660
REPOSITORIES: MassIVE
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Project description:Female Sprague-Dawley rats were randomly separated into two groups: i) trained (Ex group) and ii) sedentary (Cont group). Animals from the Ex group were adapted to treadmill exercise for two consecutive weeks, involving a gradual increase in the running time till 60 min/day at 20 m/min, 0% grade, 5 days/week. This exercise program remained constant until the end of the 54 weeks. Mitochondria isolation from 10 animals (5 Ex group and 5 Cont group) was performed using the conventional methods of differential centrifugation. Mitochondrial protein extracts were reduced with dithiothreitol, alkylated with iodoacetamide and digested with trypsin using the FASP procedure (18). Briefly, each sample was solubilized in 4 % SDS, 0.1 M DTT, 0.1 M HEPES and incubated for 30 min at 60 C. Then, samples were mixed with 0.2 mL of a solution of 8 M Urea, 0.1 M HEPES, pH 8.5 (UH solution), loaded into the filtration devices (3k Microcon, Millipore), centrifuged at 14,000 g for 20 min, and washed twice with UH solution. After centrifugation, the concentrates were alkylated with 50 mM iodoacetamide in UH solution (dark, 25 C, 20 min), and washed twice with UH solution. The concentrate was diluted with 0.1 mL of 50 mM ammonium bicarbonate (ABC) and digested overnight (37 C) with the addition of 2 ug of trypsin diluted in 30 uL of 50 mM ABC. The resulting tryptic peptides were collected by centrifugation and the filter were washed twice with 50 uL of 50 mM ABC. Eluted peptides were acidified with 10 uL of formic acid and cleaned up on a homemade Empore C18 column (3M, St. Paul, MN, USA) (ref) for subsequent phospho-enrichment and/or analysis by LC-MS/MS. The dried protein digest was dissolved with 10 uL (3 % ACN, 0.1 % TFA), diluted 1:5 with loading buffer (1 M glycolic acid, 5 % TFA, 80 % ACN) and phosphopeptides were enriched on TiO2-beads as previously described (19). Briefly 5 mg of "Titansphere TiO2 5 um" were suspended in 100 uL of 100 % ACN, immobilized in a pipette-column and washed using 5 uL of loading buffer. Each sample was loaded in each pipette-column and then washed with 30 uL of washing buffer (1 % TFA, 80 % ACN). Phosphopeptides were eluted from the beads with 25 uL of 25 % ACN (v/v) containing 25 % NH4OH (m/v), acidified with 10 uL of 10 % TFA and vacuum- concentrated to approximately 4 uL. Samples were finally diluted to 10 uL with H2O + 0.1% formic acid prior to injection. The peptides mixtures were analyzed by online nanoflow liquid chromatography tandem mass spectrometry (nanoLC-MS/MS) on an EASY-nLC system (Proxeon Biosystems, Odense, Denmark) connected to the LTQ Orbitrap Velos instrument (Thermo Fisher Scientific, Bremen, Germany) through a nanoelectrospray ion source. Six microliters of the peptide mixture were auto-sampled directly onto the analytical HPLC column (120 mm x75 um I.D., 3 um particle size (Nikkyo Technos Co., Ltd.) with a 120-min gradient from 5 % to 50 % ACN in 0.1 % FA. The effluent from the HPLC column was directly electrosprayed into the mass spectrometer. The LTQ Orbitrap Velos instrument was operated in data-dependent acquisition mode to automatically switch between full scan MS and MS/MS acquisition. The MS survey scan was performed in the FT cell recording a window between 350 and 2000 m/z. The resolution was set to 60 000, and the automatic gain control was set to 1,000,000 ions with a maximal acquisition time of 400 ms. The 20 most intense peptide ions with charge states great than or equal to 2 were sequentially isolated to a target value of 5,000 and fragmented in the high-pressure linear ion trap by low-energy CID with normalized collision energy of 35% Q value of 0.25, and an activation time of 10 ms. Raw files were processed using Proteome Discoverer version 1.3 (Thermo Fisher Scientific, Bremen). Peak lists were searched using Mascot software version 2.3 (Matrix Science, UK) against a SwissProt database containing entries corresponding to Rattus norvegicus (version of July 2012), a list of common contaminants, and all the corresponding decoy entries. Trypsin was chosen as enzyme and a maximum of two miscleavages were allowed. Carbamidomethylation (C) was set as a fixed modification, whereas oxidation (M) and phosphorylation (STY) were used as variable modifications. Searches were performed using a peptide tolerance of 7 ppm, a product ion tolerance of 0.5 Da. Resulting data files were filtered for FDR less than 1 % at peptide level.
2014-02-14 | PXD000354 | Pride
Project description:Flag-YBX1 overexpressed T24 cells pellets were resuspended with 2 volume of lysis buffer (150 mM KCl, 10 mM HEPES pH 7.6, 2 mM EDTA, 0.5% NP-40, 0.5 mM DTT, 1:100 protease inhibitor cocktail, 400 U/ml RNase inhibitor), and incubated at 4 °C for 30 min with rotation. Then the lysate was centrifuged at 15 000 g for 20 min. Before incubating the lysate with Flag beads, 100ul were taken as input. The anti-Flag M2 magnetic beads (Sigma, 10 μl per mg lysate) were washed with NT2 buffer (200 mM NaCl, 50 mM HEPES pH 7.6, 2 mM EDTA, 0.05% NP-40, 0.5 mM DTT, 200 U/ml RNase inhibitor) four times. Cell lysate was mixed with M2 beads and incubated at 4 °C for 4 h with rotation. The beads were washed two times with 1 ml ice-cold NT2 buffer. Then the beads were subject to Micrococal nuclease (NEB) digestion (1:1 000 000 dilution) for 8 min at 37 °C. The beads were cooled on ice immediately for 5 min and washed two times with 1 ml ice-cold 1× PNK+EGTA buffer (50 mM Tris-HCl pH 7.5, 20 mM EDTA, 0.05% NP-40, 200 U/ml RNase inhibitor) and two times with 1 ml ice-cold 1× PK buffer (50 mM NaCl, 100 mM Tris-HCl pH 7.5, 10 mM EDTA, 0.2% SDS, 200 U/ml RNase inhibitor). Then the beads were digested with 200 μl pre-heated (20 min at 50 °C) Proteinase K and RNAs were extracted with an equal volume of Acid-Phenol: Chloroform, pH 4.5 (Ambion). The RNAs were subjected to rRNA removal and Bisseq. The libraries were sequenced on the Illumina HiSeq X-Ten platform at Novogene (Tianjin, CA) with paired-end 150 bp read length.The m5C sites were called using meRanCall from meRanTK (FDR < 0.01).
2019-07-02 | GSE133625 | GEO
Project description:MicroPoly(A)Pure kits (Ambion) were used to prepare mRNA from P. salmonis-infected and control Atlantic salmon head kidney. Head kidney mRNA samples were prepared from pooled (n = 10) infected or control kidney. Approximately 200 ng of infected or control head kidney mRNA was used as template in aRNA synthesis reactions. Two infected head kidney samples were pooled to yield 8.9 ug of aRNA, and a single control head kidney sample contained 8.4 ug of aRNA. Infected and control head kidney aRNA samples were visualized on agarose gels to check quality and quantity (data not shown). Except for the amounts of aRNA and reverse transcription (RT) primer used, head kidney target labeling reactions and microarray hybridizations were identical. Head kidney target syntheses used 2 ug of aRNA and 2 ug of random primers (Roche). RT primers were mixed with aRNA samples, and nuclease-free H2O (Invitrogen) was added to make 10 ul total volume. Samples were incubated at 70 degrees C for 4 min, then placed on ice. RT reactions included 50 mM Tris HCl pH 8.3, 75 mM KCl, 3 mM MgCl2, 10 mM DTT, 0.5 mM each dATP, dCTP, and dGTP, 0.2 mM dTTP, 0.05 mM Cy3-dUTP or Cy5-dUTP (Amersham), 40U RNAguard ribonuclease inhibitor (Amersham), and 400U Superscript II Rnase H- reverse transcriptase (Invitrogen). RT reactions were incubated at 42 degrees C for 2.5 h, followed by addition of 0.025U RNase A (Sigma) and 1.5U RNase H (New England BioLabs) and incubation at 37 degrees C for 30 min. Labeled targets were cleaned using the Qiaquick PCR purification kit (Qiagen) and precipitated, with 300 mM sodium acetate, 1 ul of 20 ug/ul glycogen (Invitrogen), and 2.5 volumes of 100% ethanol, at -20 degrees C overnight. Each labeled target was recovered by centrifugation (14,000 rpm, 4 degrees C, 1 h), washed in 70% ethanol, air-dried, and resuspended in 60 ul of hybridization buffer: 50% deionized formamide, 5X SSC, 0.1% SDS, 5 ul of 5 ug/ul oligo dT (5’T18[Q-N]3’), 5 ul of 2 ug/ul BSA (Pierce), and 2 ul of 10 ug/ul sonicated human placental DNA (Sigma). Targets were incubated at 96 degrees C for 3 min, and then at 65 degrees C until applied to microarrays. Microarrays were prepared for hybridization by washing 2 X 5 min in 0.1% SDS, washing 5 X 1 min in MilliQ H2O, immersing 3 min in 95 degrees C MilliQ H2O, and drying by centrifugation (2000 rpm, 5 min, in 50 ml conical tube). Microarray hybridizations were run in the dark under HybriSlips hybridization covers (Grace Biolabs) in slide hybridization chambers (Corning) submerged in a 45 degrees C water bath for 16 h. Coverslips were floated off in 45 degrees C (1X SSC, 0.2% SDS), and arrays were washed 1 X 10 min in 45 degrees C (1X SSC, 0.2% SDS), 3 X 4 min in room temperature (0.1X SSC, 0.1% SDS), and 4 X 4 min in room temperature 0.1X SSC. Slides were dried by centrifugation as before. Fluorescent images of hybridized arrays were acquired immediately at 10 um resolution using ScanArray Express (PerkinElmer). The Cy3 and Cy5 cyanine fluors were excited at 543 nm and 633 nm respectively, and the same laser power (90%) and photomultiplier tube (PMT) settings were used for all slides in a study (PMT 75 Cy3, PMT 63 or 64 Cy5 for head kidney study). Fluorescent intensity data were extracted from TIF images using Imagene 5.5 software (Biodiscovery). Keywords: other
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2004-02-11 | GSE1012 | GEO
Project description:The chromatin fraction was isolated from 5x107 HeLa cells. Chromatin was digested in 100 mL of MNase (40 units/ mL ) reaction buffer for 3 min at 37 °C in a thermomixer (1,400 rpm). After addition of 10 L EGTA (25mM) to inactivate MNase, soluble digested chromatin was collected by 13,000 rpm centrifuge for 5 min. 10 mg of Pol II antibody was conjugated to magnetic protein A beads. The supernatant was diluted with 400 mL of NET-2 buffer and pSer2-Pol II antibody-conjugated beads were added. Incubated the IP reaction at 4 °C for 1 hr. The beads were washed with 1 mL of NET-2 buffer six times and 100 mL of 1xPNKT (1xPNK buffer and 0.05% Triton X-100) buffer once. Washed beads were incubated in 50 mL PNK reaction mix (1xPNKT, 1 mM ATP and 0.05 U/ml T4 PNK (NEB)) in Thermomixer at 37 °C, 1,400 rpm for 6 min. Beads were washed with 1 mL of NET-2 buffer once and RNA was extracted with Trizol reagent. RNA was suspended in urea Dye (7M Urea, 1xTBE, 0.1% BPB and 0.1% XC) and resolved on 6% TBU gel (Invitrogen) at 200 V for 5 min. Gels with 30-160 nt RNAs were collected. 0.2 mL tube was prepared with holes made with 25G needle and placed in a 1.5 mL tube. Gel fragments were placed in the layered tube and broken down by centrifugation at 12,000 rpm for 1 min. The small RNAs were eluted from gel using RNA elution buffer (1 M NaOAc and 1 mM EDTA) at 25 °C for 1 hr in Thermomixer (900 rpm). Eluted RNA was purified with SpinX column (Coster) with 2 glass filters (Millipore) and the flow-through RNA was ethanol precipitated.
2019-10-15 | GSE134102 | GEO
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2018-11-23 | PXD009622 | Pride
Project description:Sample preparation: P-AMPK+AMP, P-AMPK+ATPγS, and AMPK+ATPγS protein samples were crosslinked in HBST buffer (25 mM HEPES pH 7.5 at room temperature, 200 mM NaCL, and 1 mM TCEP). Non-crosslinked negative controls were generated using the same procedure without the addition of DSSO. Reactions were initiated by spiking 1 uL of 75 mM DSSO (Thermo-Fisher) in DMSO into a 50 uL solution containing 10 uM protein and mixing. The final molar ratio of crosslinker:protein was 150:1. The reactions were incubated at 25°C for 45 minutes prior to being quenched by the addition of Tris pH 8.0 to a final concentration of 50 mM. Each crosslink reaction was done in triplicate and the reaction replicates were pooled after quenching. 10 μL samples of the pooled samples were loaded for SDS-PAGE analysis with Coomassie staining to confirm the presence of crosslinked protein. The remaining 140 μL of crosslinked and non-crosslinked samples were then acetone precipitated at -20°C overnight and the protein was pelleted by centrifugation at 16,000 rcf for 5 minutes at 4°C. After decanting, the pellets were dried for 15 minutes at room temperature before being resuspended in 12.5 uL of resuspension buffer (50 mM ammonium bicarbonate, 8M urea, pH 8.0). ProteaseMAX (Promega) was added to 0.02% and the solutions were mixed on an orbital shaker operating at 400 RPM for 5 minutes. After resuspension, 87.5 uL of digestion buffer (50 mM ammonium bicarbonate, pH 8.0) was added. Cysteines in the protein samples were reduced and akylated as follows. DTT was added to 5 mM final concentration and the protein solutions were incubated at 56°C in an orbital shaker operating at 400 RPM and for 20 minutes. After reduction, 2.7 uL of 550 mM iodoacetamide was added and the solutions were incubated in the dark at room temperature for 15 minutes. Reduced and alkylated protein solutions were digested using trypsin at a ratio of 1:200 (w/w trypsin:protein) and incubating at 37°C. After overnight incubation at 37°C, the samples were acidified by the addition of trifluoroacetic acid (TFA, Thermo-Fischer) to 1%. Samples were then frozen and stored at -20°C until analysis.
2021-07-08 | PXD019017 | Pride
Project description:Cells were washed with cold PBS twice and scraped from the plates, then centrifuged at 1000 rpm for 5 min to pellet cells. Washed cells were lysed with 400 L of cell lysis buffer (10 mM Tris-HCl pH7.5, 150 mM NaCl, 0.15% NP-40 and proteinase inhibitor cocktail) and incubated on ice for 10 min. The suspension was carefully add at the top of sucrose buffer (10 mM Tris-HCl pH7.5, 150 mM NaCl, 24% sucrose), and centrifuged at 3200g for 10 min to collect nuclear pellets. Pellets were resuspended in 250 L of Glycerol buffer (20 mM Tris-HCl pH7.5, 75 mM NaCl, 0.5 mM EDTA pH8.0, 50% glycerol), then then immediately add 250 μl Nuclear lysis buffer (10 mM Tris-HCl pH7.5, 300 mM NaCl, 7.5 mM MgCl2, 0.2 mM EDTA pH8.0, 1% NP-40, 1M urea). Mix by vortexing for 4 s and incubate on ice for 2 min. Centrifuge the lysate at 13,000 × g for 2 min to precipitate the chromatin–RNA complex. Briefly rinse the chromatin pellets with PBS-EDTA. RNA was extracted with Trizol reagent. RNA libraries were prepared according to manual of SMARTer smRNA-Seq Kit for Illumina (Clontech, 635031).
2019-10-15 | GSE134103 | GEO
Project description:Prefrontal cortex tissue slices from a cognitively and neurpathologically normal human subject were obtained from the University of Pennsylvania (UPenn) Brain Bank. 300-350 mg grey matter was homogenized in 1.5 ml solution A (0.32 M sucrose, 1mM MgCl2 and 0.1mM CaCl2) with a Teflon pestle. ~100 ?l of the homogenate was saved, solubilized with 1% SDS and clarified by centrifugation. To prepare the [13C6]brain ISTD, 400 mg labeled MouseExpress brain tissue (Cambridge Isotopes, MA) was homogenized in 4 ml buffer A as described above, centrifuged at 1,000 x g for 10 min to clarify, agitated on a rocker at 4�C for 30 min, and centrifuged at 10,000 x g for 20 min. The pellet, a crude membrane fraction, was dissolved in 2 ml 20 mM Tris pH 7.4 with 1% SDS. Total protein in all preparations was quantified with the micro BCA assay (Pierce) and all solutions were supplemented with protease and phosphate inhibitor cocktails (Sigma) as well as 1 mM sodium fluoride and sodium orthovanadate (Sigma). Human cortex homogenate was mixed with the [13C6]brain ISTD (1?g/?l) at a ratio of 2:1(?g/?g) and processed for LC-MS/MS: 40 ?l preparations were heated with lithium dodecyl sulfate (LDS) (Invitrogen) buffer at 95�C for 20 min, separated on a 1.5 mm 4-12% Bis-Tris Gel (Invitrogen), cut into five fractions, chopped into ?2 mm cubes, washed in 200 ?l 50% acetonitrile (ACN) containing 25 mM NH4HCO3, reduced in 300 ?l 10 mM DTT, alkylated in 300 ?l 55 mM iodoacetamide (Sigma), and digested with 80-120 ?l trypsin (.025 ?g/?l) (Promega) overnight at 37�C, so that the amount of trypsin was 1:5 of the total protein to be digested by mass. Peptides were recovered from gel cubes into 200 ?l 50/50 H2O/ACN with 3% formic acid by vortex-mixing and sonication for 20 min each, twice. Samples were then evaporated to a 100 ?l volume, brought to 1ml in H20 with 0.1% formic acid, desalted with Oasis� HLB cartridges (Waters), evaporated almost to completion and suspended in ~ 45?l H2O with 0.1% formic acid, and filtered with 0.22 �m Ultra free-MC filter cartridges (Millipore). LC-data dependant -MS/MS analyses were conducted on a Q Exactive (ThermoFisher Scientific) quadrupole orbi-trap hybrid instrument with an Easy nLC-II (ThermoFisher Scientific) nano-pump/autosampler. 3?l peptide sample (~ 1 ug) was loaded and resolved on a 20 cm x 75 �m proteopepII C18 packed tip column over a 90 min gradient at a flow rate of 350 nL/min, 0-35% mobile phase B (ACN, 0.1 formic acid). A data-dependent top 10 method was used to acquire a 70,000 resolution full scan to trigger ten 17,500 resolution HCD scans. Ions were isolated for MS/MS analysis with a 2.0 Da window on the quadrupole. Average cycle times were 1.2 sec. Each sample was analyzed in triplicate. Raw files from triplicate injections were searched together within Proteome Discoverer 1.3 (ThermoFisher Scientific) using SEQUEST and the human refseq. database (release 47, ftp://ftp.ncbi.nih.gov/refseq/H_sapiens/mRNA_Prot/). Search parameters allowed trypsin to cleave after Lysine and Arginine and have 2 missed cleavages. Precursor ion mass tolerance was set to 15 ppm and fragment ion mass tolerance was 20 mmu. The dynamic modification of methionine (oxidation = 15.995 Da) and lysine (13C6 = 6.020 Da), in addition to the static modification of cysteine (carbamidomethylation = 57.021 Da) was accepted on up to 4 residues per peptide. Within the Proteome Discoverer Software, SILAC pairs were identified using the �2 plex� workflow node, and all peptides were rescored using the Percolator algorithm node. Finally, peptides were filtered at 1% false discovery rate (FDR).
2012-12-10 | PXD000004 | Pride