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https://www.readbyqxmd.com/read/28340309/analytical-techniques-in-lipidomics-state-of-the-art
#1
Kamil Jurowski, Kamila Kochan, Justyna Walczak, Małgorzata Barańska, Wojciech Piekoszewski, Bogusław Buszewski
Current studies related to lipid identification and determination, or lipidomics in biological samples, are one of the most important issues in modern bioanalytical chemistry. There are many articles dedicated to specific analytical strategies used in lipidomics in various kinds of biological samples. However, in such literature, there is lack of articles dedicated to a comprehensive review of the actual analytical methodologies used in lipidomics. The aim of this article is to characterize the lipidomics methods used in modern bioanalysis according to the methodological point of view: 1) chromatography/separation methods, 2) spectroscopic methods and 3) mass spectrometry and also hyphenated methods...
March 24, 2017: Critical Reviews in Analytical Chemistry
https://www.readbyqxmd.com/read/28339481/proteomic-analysis-of-injured-storage-roots-in-cassava-manihot-esculenta-crantz-under-postharvest-physiological-deterioration
#2
Yuling Qin, Astride Stéphanie Mouafi Djabou, Feifei An, Kaimian Li, Zhaogui Li, Long Yang, Xiaojing Wang, Songbi Chen
Postharvest physiological deterioration (PPD) is a global challenge in the improvement of cassava value chain. However, how to reduce cassava spoilage and reveal the mechanism of injured cassava storage roots in response to PPD were poorly understood. In the present study, we investigated the activities of antioxidant enzymes of cassava injured storage roots in PPD-susceptible (SC9) and PPD-tolerant (QZ1) genotypes at the time-points from 0h to 120h, and further analyzed their proteomic changes using two-dimensional electrophoresis (2-DE) in combination with MALDI-TOF-MS/MS...
2017: PloS One
https://www.readbyqxmd.com/read/28335581/biosynthesis-of-oligomeric-anthocyanins-from-grape-skin-extracts
#3
Jin-Woo Hwang, Sithranga Boopathy Natarajan, Yon-Suk Kim, Eun-Kyung Kim, Jae Woong Lee, Sang-Ho Moon, Byong-Tae Jeon, Pyo-Jam Park
We synthesized oligomeric anthocyanins from grape skin-derived monomeric anthocyanins such as anthocyanidin and proanthocyanidin by a fermentation technique using Aspergillus niger, crude enzymes and glucosidase. The biosyntheses of the oligomeric anthocyanins carried out by the conventional method using Aspergillus niger and crude enzymes were confirmed by ESI-MS. The molecular weight of the synthesized anthocyanin oligomers was determined using MALDI-MS. The yield of anthocyanin oligomers using crude enzymes was higher than that of the synthesis using Aspergillus fermentation...
March 21, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28333435/laser-desorption-ionization-coupled-to-ft-icr-mass-spectrometry-for-studies-of-natural-organic-matter
#4
John W T Blackburn, Will Kew, Margaret C Graham, Dusan Uhrin
Laser desorption/ionization (LDI) was investigated as an ionization method for Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) studies of natural organic matter (NOM). Using International Humic Substances Society standards, Suwannee River fulvic acid (SRFA) and Suwannee River natural organic matter (SRNOM), LDI was found to ionize very similar set of compounds (> 90 % of molecular formulae identity) to the matrix assisted laser desorption/ionization (MALDI), while producing higher quality spectra...
March 23, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28333351/ecological-impact-of-ciprofloxacin-on-commensal-enterococci-in-healthy-volunteers
#5
Victoire de Lastours, Elena Maugy, Vincent Mathy, Françoise Chau, Benjamin Rossi, François Guérin, Vincent Cattoir, Bruno Fantin
Background: The ecological impact of ciprofloxacin on commensal enterococci is unknown. Methods: Forty-eight healthy volunteers received ciprofloxacin from day (D) 0 to D14; stools were collected on D7, D14 and D42. Fluoroquinolone-susceptible and -resistant enterococci (FQ-SE and FQ-RE) were detected and quantified by culture, and identified by MALDI-TOF MS. The relative abundance of FQ-RE over FQ-SE was determined. The genetic basis of fluoroquinolone resistance was deciphered by partial sequencing of gyrA and parC genes...
March 4, 2017: Journal of Antimicrobial Chemotherapy
https://www.readbyqxmd.com/read/28332030/molecular-cloning-expression-and-characterization-of-pectin-methylesterase-ctpme-from-clostridium-thermocellum
#6
Vikky Rajulapati, Arun Goyal
Many phytopathogenic micro-organisms such as bacteria and fungi produce pectin methylesterases (PME) during plant invasion. Plants and insects also produce PME to degrade plant cell wall. In the present study, a thermostable pectin methylesterase (CtPME) from Clostridium thermocellum belonging to family 8 carbohydrate esterase (CE8) was cloned, expressed and purified. The amino acid sequence of CtPME exhibited similarity with pectin methylesterase from Erwinia chrysanthemi with 38% identity. The gene encoding CtPME was cloned into pET28a(+) vector and expressed using Escherichia coli BL21(DE3) cells...
March 22, 2017: Molecular Biotechnology
https://www.readbyqxmd.com/read/28330235/antimicrobial-activities-of-a-promising-glycolipid-biosurfactant-from-a-novel-marine-staphylococcus-saprophyticus-sbps-15
#7
P Mani, G Dineshkumar, T Jayaseelan, K Deepalakshmi, C Ganesh Kumar, S Senthil Balan
Biosurfactants have gained a renewed interest in the recent years for their commercial application in diverse research areas. Recent evidences suggest that the antimicrobial activities exhibited by biosurfactants make them promising molecules for the application in the field of therapeutics. Marine microbes are well known for their unique metabolic and functional properties; however, few reports are available till date regarding their biosurfactant production and antimicrobial potential. In an ongoing survey for bioactive microbial metabolites from microbes isolated from diverse ecological niches, a marine Staphylococcus saprophyticus SBPS 15 isolated from the petroleum hydrocarbon contaminated coastal site, Puducherry, India, was identified as a promising biosurfactant producer based on multiple screening methods...
December 2016: 3 Biotech
https://www.readbyqxmd.com/read/28330155/purification-and-characterization-of-rga2-a-rho2-gtpase-activating-protein-from-tinospora-cordifolia
#8
Mohd Amir, Mohammad Aasif Dar, Wahiduzzaman, Asimul Islam, Faizan Ahmad, Md Imtaiyaz Hassan
Rho GTPases activating protein 2 (RGA2) is primarily involved in the modulation of numerous morphological events in eukaryotes. It protects plants by triggering the defense system which restricts the pathogen growth. This is the first report on the isolation, purification and characterization of RGA2 from the stems of Tinospora cordifolia, a medicinal plant. The RGA2 was purified using simple two-step process using DEAE-Hi-Trap FF and Superdex 200 chromatography columns, with a high yield. The purity of RGA2 was confirmed by SDS-PAGE and identified by MALDI-TOF/MS...
June 2016: 3 Biotech
https://www.readbyqxmd.com/read/28330122/production-purification-and-characterization-of-a-thermotolerant-alkaline-serine-protease-from-a-novel-species-bacillus-caseinilyticus
#9
Thirumala Mothe, Vishnuvardhan Reddy Sultanpuram
Alkaline proteases are important enzymes in many industrial applications, especially as additives in laundry detergent industry. Though there are a number of Bacillus species which are reported to be producing proteases, the efficiency of a protease produced by a novel strain has to be studied in comparison to the others. Hence, in this study, an alkaline serine protease produced by a novel species Bacillus caseinilyticus was purified and characterized for its possible usage in detergent industry. Ammonium sulphate, dialysis and DEAE column chromatographic methods were used for purification of the isolated alkaline protease...
June 2016: 3 Biotech
https://www.readbyqxmd.com/read/28330086/cloning-expression-purification-and-characterization-of-human-mitochondrial-carbonic-anhydrase-va
#10
Danish Idrees, Sudhir Kumar, Syed Abdul Arif Rehman, Samudrala Gourinath, Asimul Islam, Faizan Ahmad, Md Imtaiyaz Hassan
Carbonic anhydrase VA (CAVA) is a mitochondrial enzyme that catalyzes the reversible hydration of CO2 to produce HCO3(-) and proton. CAV is primarily involved in several biosynthetic processes such as ureagenesis, gluconeogenesis and lipogenesis by providing bicarbonate ion. Here, we report a new strategy for cloning, expression and purification for CAVA in the bacterial system followed by its biophysical characterization. The cDNA of CAVA, a 801 nucleotide long that encodes a 267-amino acid polypeptide of molecular mass of 30-kDa (excluding signal peptide), was sub-cloned in the expression vector pET21c and transformed into Escherichia coli strain BL21 (DE3) for expression...
June 2016: 3 Biotech
https://www.readbyqxmd.com/read/28329870/application-of-imaging-techniques-to-cases-of-drug-induced-crystal-nephropathy-in-preclinical-studies
#11
B Lenz, A Brink, M Siam, A De Paepe, S Bassett, A Eichinger-Chapelon, P Maliver, R Neff, U Niederhauser, B Steinhuber, R Zurbach, T Singer, C Funk, F Schuler, M Albassam, S Schadt
A number of drugs can cause precipitates within renal tubules leading to crystal nephropathy. Crystal nephropathy is usually an exposure-related finding and is not uncommon in preclinical studies, where high doses are tested. An understanding of the nature of precipitates is important for human risk assessment and further development. Our aim was to investigate the ability of various imaging techniques to detect the presence of drugs or metabolites in renal crystals. We applied matrix-assisted laser desorption/ionization - Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) imaging, Raman and infrared microspectroscopy, scanning electron microscopy coupled with energy dispersive X-ray (SEM/EDX) spectroscopy and standard histopathology to cases of drug-induced crystal nephropathy, induced in rodents and primates by four compounds...
February 27, 2017: Toxicological Sciences: An Official Journal of the Society of Toxicology
https://www.readbyqxmd.com/read/28328038/superbasic-alkyl-substituted-bisphosphazene-proton-sponges-a-new-class-of-deprotonating-matrices-for-negative-ion-matrix-assisted-ionization-laser-desorption-mass-spectrometry-of-low-molecular-weight-hardly-ionizable-analytes
#12
C D Calvano, T R I Cataldi, J F Kögel, A Monopoli, F Palmisano, J Sundermeyer
RATIONALE: Here hardly ionizable and low molecular weight compounds are detected in negative ion mode by using novel superbasic proton sponges based on 1,8-bisphosphazenylnaphthalene (PN) as MALDI matrices. Among the selected proton sponges, 1,8-bis(trispyrrolidinophosphazenyl)naphthalene (TPPN) has shown the best behaviour as matrix since it allows the direct detection of intact cholesterol without derivatization also in real challenging samples. METHODS: Very weakly acidic compounds such as sterols, steroids, fatty alcohols and saccharides were detected in reflectron negative ion mode by a MALDI TOF/TOF system equipped with a neodymium-doped yttrium lithium fluoride (Nd:YLF) laser (345 nm) with typical mass accuracy of 10 ppm...
July 30, 2016: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28328033/effects-of-molecular-weight-and-cationization-agent-on-the-sensitivity-of-bi-cluster-secondary-ion-mass-spectrometry
#13
Makiko Fujii, Rie Shishido, Takaya Satoh, Shigeru Suzuki, Jiro Matsuo
RATIONALE: Bi cluster secondary ion mass spectrometry (SIMS) is one of the most promising tools for precise analysis of synthetic polymers. However, the sensitivity in the high-mass region is still insufficient compared with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). Accordingly, the effects of metal assistance (cationization agents) were investigated in this study. METHODS: To investigate the effects caused by varying the ionization agent, three different polyethylene glycol (PEG) samples were prepared, one with an Ag-deposited film, and two others mixed with Ag and Na, respectively...
July 30, 2016: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28328023/identification-of-microorganisms-in-biofluids-of-individuals-with-periodontitis-and-chronic-kidney-disease-using-matrix-assisted-laser-desorption-ionization-time-of-flight-mass-spectrometry
#14
Levy Anderson César Alves, Rafael Celestino Souza, Taciana Mara Couto da Silva, Andreia Watanabe, Meriellen Dias, Maria Anita Mendes, Ana Lídia Ciamponi
RATIONALE: Chronic kidney disease (CKD) and periodontitis (PD) are important health issues. There is a large variety of microorganisms related to the pathogenesis of periodontitis, and optimising the time and the cost of laboratory assays to detect these organisms is highly valuable in the medical field. METHODS: Bacteria were isolated from saliva and oral biofilm of 30 adolescents and young adults with definite medical and dental diagnosis of CKD and PD, respectively, and proteins were extracted for microorganism identification by means of the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) technique...
May 30, 2016: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28328018/abundance-correction-for-mass-discrimination-effects-in-polymer-mass-spectra
#15
Martin S Engler, Sarah Crotty, Markus J Barthel, Christian Pietsch, Ulrich S Schubert, Sebastian Böcker
RATIONALE: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) is frequently used to analyze homo- and copolymers, i.e. for computing copolymer fingerprints. However, the oligomer abundances are influenced by mass discrimination, i.e. mass- and composition-dependent ionization. We have developed a computational method to correct the abundance bias caused by the mass discrimination. METHODS: MALDI-TOFMS in combination with computational methods was used to investigate three random copolymers with different ratios of styrene and isoprene...
May 30, 2016: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28327300/rbaltmip-a-recombinant-alpha-type-myotoxin-inhibitor-from-bothrops-alternatus-rhinocerophis-alternatus-snake-as-a-potential-candidate-to-complement-the-antivenom-therapy
#16
Norival A Santos-Filho, Tiago S Sousa, Johara Boldrini-França, Ludier K Santos-Silva, Danilo L Menaldo, Flávio Henrique-Silva, Adélia C O Cintra, Helen J Laure, Carla C N Mamede, Fábio Oliveira, Thalita B Riul, Marcelo Dias-Baruffi, José C Rosa, Suely V Sampaio
Phospholipase A2 inhibitors (PLIs) are important targets in the search and development of new drugs. This study aimed at evaluating the potential of an alpha-type phospholipase A2 inhibitor from Bothrops alternatus (Rhinocerophis alternatus) snake in its recombinant form (rBaltMIP) to complement the conventional antivenom therapy. Biochemical experiments showed that rBaltMIP presented pI 5.8 and molecular masses of ∼21 kDa by SDS-PAGE and 19.57 kDa by MALDI/TOF MS. After tryptic peptides sequencing, the results were compared with other PLIs available in databases, showing 100% identity between rBaltMIP and its native inhibitor BaltMIP and from 92% to 96% identity with other inhibitors...
December 15, 2016: Toxicon: Official Journal of the International Society on Toxinology
https://www.readbyqxmd.com/read/28326685/hugonella-massiliensis-gen-nov-sp-nov-genome-sequence-and-description-of-a-new-strictly-anaerobic-bacterium-isolated-from-the-human-gut
#17
Ziena Elsawi, Amadou Hamidou Togo, Mamadou Beye, Grégory Dubourg, Claudia Andrieu, Nicholas Armsrtong, Magali Richez, Fabrizio di Pinto, Fadi Bittar, Noémie Labas, Pierre-Edouard Fournier, Didier Raoult, Saber Khelaifia
The human gut is composed of a large diversity of microorganisms, which have been poorly described. Here, using culturomics, a new concept based on the variation in culture conditions and MALDI-TOF MS identification, we proceed to explore the microbial diversity of the complex ecosystem of the human gut. Using this approach, we isolated strain AT8(T) (=CSUR P2118 =  DSM 101782) from stool specimens collected from a 51-year-old obese French woman. Strain AT8(T) is a strictly anaerobic, nonmotile, nonspore-forming gram-positive coccus that do not exhibit catalase and oxidase activities...
March 21, 2017: MicrobiologyOpen
https://www.readbyqxmd.com/read/28326061/come-an-essential-response-regulator-negatively-regulates-the-expression-of-the-capsular-polysaccharide-locus-and-attenuates-the-bacterial-virulence-in-streptococcus-pneumoniae
#18
Yuqiang Zheng, Xuemei Zhang, Xiaofang Wang, Libin Wang, Jinghui Zhang, Yibing Yin
The capsular polysaccharide (CPS) of Streptococcus pneumoniae is the main virulence factors required for effective colonization and invasive disease. The capacity to regulate CPS production at the transcriptional level is critical for the survival of S. pneumoniae in different host niches, but little is known about the transcription regulators of cps locus. In the present study, we isolated and identified the response regulator ComE, the master competence switch in transformation of S. pneumoniae, as a transcriptional regulator of cps locus by DNA affinity chromatography-pulldown, MALDI-TOF mass spectrometry (MS) and electrophoretic mobility shift assay (EMSA)...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28325940/one-pot-synthesis-of-four-coordinate-boron-iii-complexes-by-the-ligand-promoted-organic-group-migration-between-boronic-acids
#19
Venkata S Sadu, Hye-Rin Bin, Do-Min Lee, Kee-In Lee
Multidisciplinary applications of four-coordinate boron(III) complexes make them very attractive and challenging research field in chemistry, biology and material sciences. The dual role played by boron atom in stabilising the chelate ligand and enhancing the π-conjugation makes them very useful as luminescent materials for organic electronics and photonics, and sensing and imaging probes for biomedical purposes. The conventional methods involve the use of diarylborinic acids or anhydrides and triaryl boranes, which are made from organometallic reagents...
March 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28323431/au38-sph-24-au38-protected-with-aromatic-thiolate-ligands
#20
Milan Rambukwella, Shayna Burrage, Marie Neubrander, Oscar Baseggio, Edoardo Aprà, Mauro Stener, Alessandro Fortunelli, Amala Dass
Au38(SR)24 is one of the most extensively investigated gold nanomolecules along with Au25(SR)18 and Au144(SR)60. However, so far it has only been prepared using aliphatic-like ligands, where R = -SC6H13, -SC12H25 and -SCH2CH2Ph. Au38(SCH2CH2Ph)24 when reacted with HSPh undergoes core-size conversion to Au36(SPh)24, and existing literature suggests that Au38(SPh)24 cannot be synthesized. Here, contrary to prevailing knowledge, we demonstrate that Au38(SPh)24 can be prepared if the ligand exchanged conditions are optimized, under delicate conditions, without any formation of Au36(SPh)24...
March 21, 2017: Journal of Physical Chemistry Letters
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