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Ammonium Formate (ammonium + formate)
Terms modified by Ammonium Formate Selected AbstractsChemInform Abstract: Synthesis of Indolones and Quinolones by Reductive Cyclization of o-Nitroaryl Acids Using Zinc Dust and Ammonium Formate.CHEMINFORM, Issue 46 2008Bhima Reddy Dinesh Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Mild and Efficient Deprotection of Allyl Ethers of Phenols and Hydroxycoumarins Using a Palladium on Charcoal Catalyst and Ammonium Formate.CHEMINFORM, Issue 47 2006Nemai C. Ganguly Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] ChemInform Abstract: Catalytic Transfer Hydrogenation of Aromatic Nitro Compounds by Employing Ammonium Formate and 5% Platinum on Carbon.CHEMINFORM, Issue 1 2001D. Channe Gowda Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Simultaneous determination of six non-polar heterocyclic amines in meat samples by supercritical fluid extraction,capillary electrophoresis under fluorimetric detectionELECTROPHORESIS, Issue 13 2010Fernando De Andrés Abstract A novel, sensitive and selective method for the separation and quantification of a group of non-polar heterocyclic amines (9H-pyrido-[3,4-b] indole, norharmane; 1-methyl-9H-pyrido-[3,4-b] indole, harmane; 2-amino-9H-pyrido-[2,3-b] indole, A,C; 2-amino-3-methyl-9H-pyrido-[2,3-b] indole, MeA,C; 3-amino-1,4-dimethyl-5H-pyrido-[4,3-b] indole, Trp-P-1 and 3-amino-1-methyl-5H-pyrido-[4,3-b] indole, Trp-P-2) in commercial meat samples has been developed. This methodology is faster than others previously described. The method is based on the combination of a supercritical fluid extraction procedure, followed by the analysis of the extracted plug by CE with fluorescence detection. The supercritical fluid extraction procedure was optimized for the clean-up of the samples and the extraction of the analytes. For the electrophoretic separation, the effect of composition, pH and concentration of buffer, organic modifier content, pressure and time of injection, capillary temperature and voltage applied were studied. A 10,mmol/L formic acid,ammonium formate,ACN (10%, v/v) solution at pH 1.5 was selected as the running electrolyte. With 5-s hydrodynamic injection, linear responses in the range from 100 to 1000,ng/mL and detection limits ranging from 15.9 to 28.1,ng/mL were obtained for different amines in less than 13,min. ACN,water (1:1 in volume) was used as a sample solvent. Fluorescence detection enhances the sensitivity and avoids interferences coming from non-fluorescent compounds present in the matrices of the sample extracts. [source] Heart-cutting 2D-CE with on-line preconcentration for the chiral analysis of native amino acidsELECTROPHORESIS, Issue 6 2010Suzanne Anouti Abstract The use of transient moving chemical reaction boundary (tMCRB) was investigated for the on-line preconcentration of native amino acids in heart-cutting 2D-CE with multiple detection points using contactless conductivity detection. The tMCRB focusing was obtained by using ammonium formate (pH 8.56) as sample matrix and acetic acid (pH 2.3) as a BGE in the first dimension of the heart-cutting 2D-CE. Different experimental parameters such as the injected volume and the concentration in ammonium formate were optimized for improving the sensitivity of detection. A stacked fraction from the first dimension was selected, isolated in the capillary, and then separated in the second dimension in the presence of a chiral selector ((+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid). This on-line tMCRB preconcentration coupled with heart-cutting 2D-CE was applied with success to the chiral separation of D,L -phenylalanine, and D,L -threonine in a mixture of 22 native amino acids. The sample mixture was diluted in 0.8,M of ammonium formate, and injected at a concentration of 2.5,,M for each enantiomer with a volume corresponding to 10% of the total capillary volume. An LOD (S/N=3) of 2,,M was determined for L -threonine. [source] Analyses of alkaloids in different products by NACE-MSELECTROPHORESIS, Issue 22 2007Chen-Wen Chiu Abstract A simple method for the separation and characterization of five nicotine-related alkaloids by NACE employing UV and MS detections is described here for the first time. Several factors, including NACE parameters (compositions of running solution) and MS parameters (such as nature and flow rate of sheath liquid, pressure of nebulization gas, and flow rate of dry gas), were optimized in order to obtain both an adequate CE separation and high MS signals for the alkaloid compounds used in this study. A reliable CE separation of five alkaloids was achieved in 50,mM ammonium formate that was dissolved in an ACN/methanol mixture (50:50, v/v) of pH*,4.0 (apparent pH 4.0). The optimal electrospray MS measurement was carried out in the positive ionization mode using a coaxial sheath liquid composed of isopropyl alcohol and water in the ratio of 80:20 v/v at a flow rate of 180,,L/h. In addition, the proposed NACE method was also applied in the analyses of alkaloids in several products including chewing gums, beverages, and tobaccos. This NACE-MS method was found to provide a better detection ability and separation resolution for the analysis of nicotine alkaloids when compared to other aqueous CE-MS reports. [source] Validation of an LC,MS Method for the Detection and Quantification of BZP and TFMPP and their Hydroxylated Metabolites in Human Plasma and its Application to the Pharmacokinetic Study of TFMPP in Humans,JOURNAL OF FORENSIC SCIENCES, Issue 5 2010Ushtana Antia M.Sc. Abstract:, An LC,MS method was developed for benzylpiperazine (BZP) and trifluoromethylphenylpiperazine (TFMPP), constituents of "party pills" or "legal herbal highs," and their metabolites in human blood plasma. Compounds were resolved using a mixture of ammonium formate (pH 4.5, 0.01 M) and acetonitrile (flow rate of 1.0 mL/min) with a C18 column. Calibration curves were linear from 1 to 50 ng/mL (R2 > 0.99); the lower limit of quantification (LLOQ) was 5 ng/mL; the accuracy was >90%; the intra- and interday relative standard deviations (R.S.D) were <5% and <10%, respectively. Human plasma concentrations of TFMPP were measured in blood samples taken from healthy adults (n = 6) over 24 h following a 60-mg oral dose of TFMPP: these peaked at 24.10 ng/mL (±1.8 ng/mL) (Cmax) after 90 min (Tmax). Plasma concentrations of 1-(3-trifluoromethyl-4-hydroxyphenyl) piperazine peaked at 20.2 ng/mL (±4.6 ng/mL) after 90 min. TFMPP had two disposition phases (t½ = 2.04 h (±0.19 h) and 5.95 h (±1.63 h). Apparent clearance (Cl/F) was 384 L/h (±45 L/h). [source] Screening, library-assisted identification and validated quantification of 23 benzodiazepines, flumazenil, zaleplone, zolpidem and zopiclone in plasma by liquid chromatography/mass spectrometry with atmospheric pressure chemical ionizationJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 8 2004Carsten Kratzsch Abstract A liquid chromatographic/mass spectrometric assay with atmospheric pressure chemical ionization (LC/APCI-MS) is presented for fast and reliable screening and identification and also for precise and sensitive quantification in plasma of the 23 benzodiazepines alprazolam, bromazepam, brotizolam, camazepam, chlordiazepoxide, clobazam, clonazepam, diazepam, flunitrazepam, flurazepam, desalkylflurazepam, lorazepam, lormetazepam, medazepam, metaclazepam, midazolam, nitrazepam, nordazepam, oxazepam, prazepam, temazepam and tetrazepam, triazolam, their antagonist flumazenil and the benzodiazepine BZ1 (omega 1) receptor agonists zaleplone, zolpidem and zopiclone. It allows confirmation of the diagnosis of an overdose situation and monitoring of psychiatric patients' compliance. The analytes were isolated from plasma using liquid,liquid extraction and were separated on a Merck LiChroCART column with Superspher 60 RP Select B as the stationary phase. Gradient elution was performed using aqueous ammonium formate and acetonitrile. After screening and identification in the scan mode using the authors' LC/MS library, the analytes were quantified in the selected-ion monitoring mode. The quantification assay was fully validated. It was found to be selective proved to be linear from sub-therapeutic to over therapeutic concentrations for all analytes, except bromazepam. The corresponding reference levels the assay's accuracy and precision data for all studied substances are listed. The accuracy and precision data were within the required limits with the exception of those for bromazepam. The analytes were stable in frozen plasma for at least 1 month. The validated assay was successfully applied to several authentic plasma samples from patients treated or intoxicated with various benzodiazepines or with zaleplone, zolpidem or zopiclone. It has proven to be appropriate for the isolation, separation, screening, identification and quantification of the drugs mentioned above in plasma for clinical toxicology, e.g. in cases of poisoning, and forensic toxicology, e.g. in cases of driving under the influence of drugs. Copyright © 2004 John Wiley & Sons, Ltd. [source] Validated assay for quantification of oxcarbazepine and its active dihydro metabolite 10-hydroxycarbazepine in plasma by atmospheric pressure chemical ionization liquid chromatography/mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 7 2002Hans H. Maurer Abstract Oxcarbazepine (OX), a new antiepileptic, may lead to unwanted side-effects or even life-threatening intoxications after overdose. Therefore, a validated liquid chromatographic/mass spectrometric (LC/MS) assay was developed for the quantification of OX and its pharmacologically active dihydro metabolite (dihydrooxcarbazepine, DOX, often named 10-hydroxycarbazepine). OX and DOX were extracted from plasma by the authors' standard liquid/liquid extraction and were separated on a Merck LiChroCART column with Superspher 60 RP Select B as the stationary phase. Gradient elution was performed using aqueous ammonium formate and acetonitrile. The compounds were quantified in the selected-ion monitoring mode using atmospheric pressure chemical ionization electrospray LC/MS. The assay was fully validated. It was found to be selective. The calibration curves were linear from 0.1 to 50 mg l,1 for OX and DOX. Limits of quantification were 0.1 mg l,1 for OX and DOX. The absolute recoveries were between 60 and 86%. The accuracy and precision data were within the required limits. The analytes in frozen plasma samples were stable for at least 1 month. The method was successfully applied to several authentic plasma samples from patients treated or intoxicated with OX. The measured therapeutic plasma levels ranged from 1 to 2 mg l,1 for OX and from 10 to 40 mg l,1 for DOX. The validated LC/MS assay proved to be appropriate for quantification of OX and DOX in plasma for clinical toxicology and therapeutic drug monitoring purposes. The assay is part of a general analysis procedure for the isolation, separation and quantification of various drugs and for their full-scan screening and identification. Copyright © 2002 John Wiley & Sons, Ltd. [source] Analysis of S -adenosylmethionine and related sulfur metabolites in bacterial isolates of Pseudomonas aeruginosa (BAA-47) by liquid chromatography/electrospray ionization coupled to a hybrid linear quadrupole ion trap and Fourier transform ion cyclotron resonance mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 21 2009Tommaso R. I. Cataldi A comprehensive and highly selective method for detecting in bacterial supernatants a modified sulfur nucleoside, S -adenosyl-L-methionine (SAM), and its metabolites, i.e., S -adenosylhomocysteine (SAH), adenosine (Ado), 5,-deoxy-5,-methylthioadenosine (MTA), adenine (Ade), S -adenosyl-methioninamine (dcSAM), homocysteine (Hcy) and methionine (Met), was developed. The method is based on reversed-phase liquid chromatography with positive electrospray ionization (ESI+) coupled to a hybrid linear quadrupole ion trap (LTQ) and 7-T Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS). A gradient elution was employed with a binary solvent of 0.05,M ammonium formate at pH 4 and acetonitrile. The assay involves a simultaneous cleanup of cell-free bacterial broths by solid-phase extraction and trace enrichment of metabolites with a 50-fold concentration factor by using immobilized phenylboronic and anion-exchange cartridges. While the quantitative determination of SAM was performed using stable-isotope-labeled SAM-d3 as an internal standard, in the case of Met and Ade, Met- 13C and Ade- 15N2 were employed as isotope-labeled internal standards, respectively. This method enabled the identification of SAM and its metabolites in cell-free culture of Pseudomonasaeruginosa grown in Davis minimal broth (formulation without sulphur organic compounds), with routine sub-ppm mass accuracies (,0.27,±,0.68,ppm). The resulting contents of SCSS -SAM, SS -dcSAM, MTA, Ado and Met in the free-cell supernatant of P. aeruginosa was 56.4,±,2.1,nM, 32.2,±,2.2,nM, 0.91,±,0.10,nM, 19.6,±,1.2,nM and 1.93,±,0.02,µM (mean,±,SD, n,=,4 extractions), respectively. We report also the baseline separation (Rs ,1.5) of both diastereoisomeric forms of SAM (SCSS and SCRS) and dcSAM (SS and RS), which can be very useful to establish the relationship between the biologically active versus the inactive species, SCSS/SCRS and SS/RS of SAM and dcSAM, respectively. An additional confirmation of SAM-related metabolites was accomplished by a systematic study of their MS/MS spectra. Copyright © 2009 John Wiley & Sons, Ltd. [source] Determination of paclitaxel in human plasma following the administration of Genaxol or Genetaxyl by liquid chromatography/tandem mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 14 2006Erin R. Gardner A sensitive and specific assay for paclitaxel in plasma has been developed to overcome limitations in previously published assays, using liquid chromatography with tandem mass spectrometric detection. Plasma samples (100,µL) were subjected to liquid-liquid extraction with 1-chlorobutane/acetonitrile (4:1, v/v), with [2H5]paclitaxel employed as the internal standard. Chromatography was carried out with a Waters SymmetryShield C8 column (50,×,2.1 mm, 3.5,µm). The total run time, including equilibration, was 8 min, using a gradient of acetonitrile and 10,mM ammonium formate, pH 4.0. The assay is accurate and precise over the range of 2,2500,ng/mL and has been successfully applied to study the clinical pharmacokinetics of two formulations of paclitaxel, Genaxol and Genetaxyl, given orally and intravenously. Copyright © 2006 John Wiley & Sons, Ltd. [source] Utility of nonaqueous capillary electrophoresis for the determination of lidocaine and its metabolites in human plasma: a comparison of ultraviolet and mass spectrometric detectionRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 22 2004Magnus S. Anderson A nonaqueous capillary electrophoresis/electrospray mass spectrometry method for the separation of lidocaine (LID) and two of its metabolites, monoethylglycinexylidide (MEGX) and glycinexylidide (GX), has been developed. The separation medium was: 70,mM ammonium formate and 2.0,M formic acid in acetonitrile/methanol (60:40 v/v). With a sheath liquid of methanol/water (80:20 v/v) containing 2% formic acid and positive ion detection, reproducible determinations (8,11% relative standard deviation (RSD)) of lidocaine and its metabolites were performed in spiked human plasma. The limits of detection (LODs) were between 69.1 and 337,nM. The influences of sheath liquid composition, nebulizing gas pressure and drying gas temperature on the separation were examined. Copyright © 2004 John Wiley & Sons, Ltd. [source] Analysis of pyridoquinoline derivatives by liquid chromatography/atmospheric pressure chemical ionization mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2001Y. Picó A method using liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCI-MS) has been developed for the characterization and determination of pyridoquinoline derivatives 4,6-bis(dimethylaminoethylamino)-2,8,10-trimethylpyrido[3,2-g]quinoline, 4,6-bis(dimethylaminoethoxy)-2,8,10-trimethylpyrido[3,2-g]quinoline and 4,6-bis[(dimethylaminoethyl)thio]-2,8,10-trimethylpyrido[3,2-g] quinoline, all with potential antitumor properties. LC separation was performed on a conventional C18 column using a binary mobile phase composed of acetonitrile and 50,mM aqueous ammonium formate at pH 3. The APCI mass spectra obtained showed that proton addition giving [M,+,H]+ was the common mode of ionization to the amino- and thiopyridoquinolines, whereas the alkoxypyridoquinoline was identified by the main formation of the [M,,,(C2H3)N(CH3)2,+,H]+, followed by the [M,+,H]+ ion. The LC separation conditions and MS detection parameters were optimized for the determination. The analytical method was also applied to the determination of these pyridoquinoline derivatives in fetal calf serum using liquid-liquid extraction with dichloromethane. Acceptable recovery values were obtained, ranging between 45 and 98%. Copyright © 2001 John Wiley & Sons, Ltd. [source] Determination and toxicokinetics comparison of ketamine and S(+)-ketamine in dog plasma by HPLC-MS methodBIOMEDICAL CHROMATOGRAPHY, Issue 3 2010Yu-xin Sheng Abstract ;A simple and reproducible method was developed for the quantification of ketamine and S(+)-ketamine in dog plasma using a high-performance liquid chromatography system coupled to a positive ion electrospray mass spectrometric analysis. Solid-phase extraction was used for extracting analytes from dog plasma samples. The analytes were separated on a Zorbax SB C18 column (100 × 2.1 mm, 3.5 ,m) with acetonitrile,formate buffer (10 mM ammonium formate and 0.3% formic acid) (17 : 83, v/v) as mobile phase at a flow-rate of 0.2 mL/min. Detection was operated under selected ion monitoring mode. [M + H]+ at m/z 238 for ketamine and S(+)-ketamine and [M + H]+ at m/z 180 for phenacetin (internal standard) were selected as detecting ions, respectively. The method was linear in the concentration range 51.6,2580 ng/mL. The intra- and inter-day precisions (RSD %) were within 11.3% and the assay accuracies ranged from 80.0 to 101.4%. Their average recoveries were greater than 91.1% at all test concentrations. The analytes were proved to be stable during all sample storage, preparation and analysis procedures. The method was successfully applied to the toxicokinetics study and comparison of ketamine and S (+)-ketamine following intravenous administration to dogs. Copyright © 2009 John Wiley & Sons, Ltd. [source] Development and validation of a highly sensitive and robust LC-ESI-MS/MS method for simultaneous quantitation of simvastatin acid, amlodipine and valsartan in human plasma: application to a clinical pharmacokinetic study,BIOMEDICAL CHROMATOGRAPHY, Issue 6 2009Addepalli V. Ramani Abstract A high-throughput, simple, highly sensitive and specific LC-MS/MS method has been developed for simultaneous estimation of simvastatin acid (SA), amlodipine (AD) and valsartan (VS) with 500 µL of human plasma using deuterated simvastatin acid as an internal standard (IS). The API-4000 LC-MS/MS was operated under the multiple reaction-monitoring mode (MRM) using electrospray ionization. The assay procedure involved precipitation of SA, AD, VS and IS from plasma with acetonitrile. The total run time was 2.8 min and the elution of SA, AD, VS and IS occurred at 1.81, 1.12, 1.14 and 1.81 min, respectively; this was achieved with a mobile phase consisting of 0.02 m ammonium formate (pH 4.5):acetonitrile (20:80, v/v) at a flow rate of 0.50 mL/min on an X-Terra C18 column. A linear response function was established for the range of concentrations 0.5,50 ng/mL (r > 0.994) for VS and 0.2,50 ng/mL (r > 0.996) for SA and AD. The method validation parameters for all three analytes met the acceptance as per FDA guidelines. This novel method has been applied to human pharmacokinetic study. Copyright © 2009 John Wiley & Sons, Ltd. [source] Multiresidue analysis of 47 pesticides in cooked wheat flour and polished rice by liquid chromatography with tandem mass spectrometry ,BIOMEDICAL CHROMATOGRAPHY, Issue 4 2009Sung Jung Lee Abstract Liquid chromatography in conjunction with tandem mass spectrometry was used to directly quantify of 47 pesticide residues from cooked wheat flour and polished rice, which are the most widely consumed cereals in the Republic of Korea. The sample clean-up was carried out according to the method established by the Korea Food and Drug Administration. The mobile phase for liquid chromatograpy separation consisted of water and 5 mm methanolic ammonium formate. Tandem mass spectroscopy experiments were performed in electrospray ionization positive mode and the multiple reaction monitoring mode. The matrix effects estimated for the 47 pesticides had a mean value of 99% and ranged from 45 to 147%. High recoveries (70,140%) and relative standard deviations (,20%) were achieved for most of the pesticides tested. The method used in this study allowed for rapid quantification and identification of low levels of pesticides in cooked wheat flour and polished rice samples. Of the screened pesticide residues, only tricyclazole and fenobucarb were found in polished rice samples. However, no samples contained residues above the MRL established by the Korea Food and Drug Administration. Copyright © 2008 John Wiley & Sons, Ltd. [source] Effect of chemically bonded stationary phases and mobile phase composition on , -blockers retention in RP-HPLCBIOMEDICAL CHROMATOGRAPHY, Issue 3 2009Boguslaw Buszewski Abstract The effects of stationary and mobile phase on retention of 18 , -adrenolytic drugs (, -blockers) have been studied. Four ,deactivated surface' stationary phases (polar-embedded or end-capped) were examined. Special attention was drawn to the cholesterolic (SG-CHOL) and alkylamide (SG-AP) stationary phases, and their application for analysis of the compounds. The retention of analyzed substances was also examined in terms of mobile phase composition. Sixteen different configurations of mobile phases were prepared, all based on methanol and acetonitrile with ammonium acetate and ammonium formate. The difference in retention between ammonium formate and acetate water solutions, and peak shape changes related to the addition of triethylamine (TEA), were investigated. Principal component analysis was used to find the similarities between stationary phases. Polar-embedded phases synthesized on the same sorbent possess very similar properties. All phases based on silica gel compared with the monolithic column also showed similarities in retention of , -blockers. The addition of TEA to the mobile phase did not influence strongly the retention, and analysis of asymmetry factors showed only a little peak broadening for a few compounds on the monolithic column. Copyright © 2008 John Wiley & Sons, Ltd. [source] Liquid chromatography-tandem mass spectrometry for the determination of a new oxazolidinone antibiotic DA-7867 in human plasmaBIOMEDICAL CHROMATOGRAPHY, Issue 2 2004Hye Young Ji Abstract A liquid chromatography-tandem mass spectrometric (LC/MS/MS) method for the determination of a new ox-azolidinone antibiotic DA-7867, (S)-[N -3-(4-(2-(1-methyl-5-tetrazolyl)-pyridine-5-yl)-3-,uorophenyl)-2-oxo-5-oxazolidinyl]methyl acetamide, in human plasma was developed. DA-7867 and internal standard, linezolid, were extracted from human plasma with ethyl acetate at acidic pH. A reverse-phase LC separation was performed on Luna C8 column with the mixture of acetonitrile,ammonium formate (10 mm, pH 4.5; 35:65, v/v) as mobile phase. The analytes were determined using an electrospray ionization tandem mass spectrometry in the multiple-reaction-monitoring mode. The lower limits of quanti,cation for DA-7867 was 2.5 ng/mL. The single liquid,liquid extraction quantitatively recovered DA-7867 and internal standard from plasma samples at the ranges of 82.2,86.7%. DA-7867 was stable in blank human plasma at room temperature for 24 h and following three freeze,thaw cycles. Copyright © 2003 John Wiley & Sons, Ltd. [source] Purification, crystallization and preliminary structural analysis of nucleoside diphosphate kinase from Bacillus anthracisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 12 2007Gauri Misra Bacillus anthracis nucleoside diphosphate kinase (BaNdk) is an enzyme whose primary function is to maintain deoxynucleotide triphosphate (dNTP) pools by converting deoxynucleotide diphosphates to triphosphates using ATP as the major phosphate donor. Although the structures of Ndks from a variety of organisms have been elucidated, the enzyme from sporulating bacteria has not been structurally characterized to date. Crystals of the B. anthracis enzyme were grown using the vapour-diffusion method from a hanging drop consisting of 2,µl 10,mg,ml,1 protein in 50,mM Tris,HCl pH 8.0, 50,mM NaCl, 5,mM EDTA equilibrated against 500,µl reservoir solution consisting of 2.25,M ammonium formate and 0.1,M HEPES buffer pH 7.25. Diffraction data extending to 2.0,Å were collected at room temperature from a single crystal with unit-cell parameters a = b = 107.53, c = 52.3,Å. The crystals are hexagonal in shape and belong to space group P6322. The crystals contain a monomer in the asymmetric unit, which corresponds to a Matthews coefficient (VM) of 2.1,Å3,Da,1 and a solvent content of about 36.9%. [source] | ||||||||||