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MALDI and matrix

Caiyun He, Guori Gao, Jianguo Zhang, Aiguo Duan, Hongmei Luo
BACKGROUND: Low temperature is one of the crucial environmental factors limiting the productivity and distribution of plants. Sea buckthorn (Hippophae rhamnoides L.), a well recognized multipurpose plant species, live successfully in in cold desert regions. But their molecular mechanisms underlying cold tolerance are not well understood. METHODS: Physiological and biochemical responses to low-temperature stress were studied in seedlings of sea buckthorn. Differentially expressed protein spots were analyzed using multiplexing fluorescent two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with matrix-assisted laser desorption/ionization (MALDI) time-of-flight/time-of-flight (TOF/TOF) mass spectrometry (MS), the concentration of phytohormone was measured using enzyme-linked immunosorbent assay, and a spectrophotometric assay was used to measure enzymatic reactions...
2016: Proteome Science
Katia Roberta A Belaz, Alessandra Tata, Moana R França, Maressa I Santos da Silva, Pedro Henrique Vendramini, Anna Maria A P Fernandes, Fábio L D'Alexandri, Marcos N Eberlin, Mario Binelli
Phospholipid metabolism and signaling influences on early pregnancy events in cattle are unknown. This study aimed to characterize global phospholipid composition of oviduct and uterus during early diestrus in a model of contrasting embryo receptivity. Beef cows were treated to ovulate a larger (LF-LCL group, associated with greater receptivity) or smaller follicle (SF-SCL group) and, consequently, to present greater or smaller plasma concentrations of estradiol during proestrus-estrus as well as progesterone during early diestrus...
October 19, 2016: Biology of Reproduction
T Banach, M Bochniarz, P Łyp, Ł Adaszek, W Wawron, B Furmaga, M Skrzypczak, J Ziętek, S Winiarczyk
The aim of this study was to use matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of coagulase-negative staphylococci (CNS) isolated from the milk of cows with subclinical mastitis. The study material consisted of 33 isolates of CNS, identified by the results of API Staph tests, obtained from the milk of cows with subclinical mastitis. Based on the spectra analyses, MALDI-TOF MS tests of 33 bacterial samples allowed identification of the microorganisms in 27 cases (81...
September 1, 2016: Polish Journal of Veterinary Sciences
Rima Ait-Belkacem, Marialaura Dilillo, Davide Pellegrini, Avinash Yadav, Erik L de Graaf, Liam A McDonnell
Atmospheric pressure MALDI on a Q-Exactive instrument was optimized for in-source decay and pseudo-MS(3). The dependence of AP-MALDI ISD on the MALDI liquid matrix was investigated for peptides and proteins. The liquid matrices enabled long-life ISD signal, and exhibited high fragment ion yield and signal stability. Extensive a-, b-, c-, y-, and z-type fragment series were observed depending on the matrix used but were most extensive with 2,5-DHB. Complete sequence coverage of small peptide and intact protein-terminus sequence tags were obtained and confirmed using HCD as a pseudo-MS(3) method...
October 17, 2016: Journal of the American Society for Mass Spectrometry
Jun Hwa Lee, Byong Chul Yoo, Yun Hwan Kim, Sun-A Ahn, Seung-Gu Yeo, Jae Youl Cho, Kyung-Hee Kim, Seung Cheol Kim
BACKGROUND: A low-mass-ion discriminant equation (LOME) was constructed to investigate whether systematic low-mass-ion (LMI) profiling could be applied to ovarian cancer (OVC) screening. RESULTS: Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry was performed to obtain mass spectral data on metabolites detected as LMIs up to a mass-to-charge ratio (m/z) of 2500 for 1184 serum samples collected from healthy individuals and patients with OVC, other types of cancer, or several types of benign tumor...
2016: BioData Mining
Syed Ghulam Musharraf, Mariam Ameer, Arslan Ali
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) being soft ionization technique, has become a method of choice for high-throughput analysis of proteins and peptides. In this study, we have explored the potential of atypical anti-psychotic drug olanzapine (OLZ) as a matrix for MALDI-MS analysis of peptides aided with the theoretical studies. Seven small peptides were employed as target analytes to check performance of olanzapine and compared with conventional MALDI matrix α-cyano-4-hydroxycinnamic acid (HCCA)...
October 5, 2016: Journal of Pharmaceutical and Biomedical Analysis
Guangming Gong, Wenya Liu, Shudong Wang
This study aimed to reduce the cytotoxicity and improve the targeting of aclacinomycin (ACM) by covalently coupling it with amino-oxyacetic acid (AOA) to generate an active intermediate, AOA-ACM. AOA-ACM was conjugated with self-assembled human serum albumin (HSA) nanoparticles constructed using tris(2-carboxyethyl)phosphine (TCEP) as disulfide bond breaking molecules in an 'opening stage-intermediate-closing stage' route, in which the hydrophobic interaction, interchange of sulfhydryl and hydrogen bond may be the key factors in the assembling process...
October 17, 2016: Nanotechnology
Xin Zhou, Ping Wang, Ying-Jian Zhang, Jin-Jin Xu, La-Mei Zhang, Lin Zhu, Li-Ping Xu, Xiao-Min Liu, Huan-Huan Su
The present study aimed to investigate the proteomic difference between melanosis coli (MC) alone and melanosis coli with colon cancer (MCCC). Protein expression in patients with different diseases was analyzed using two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/TOF-MS). A total of 14 protein differences with a confidence level of >95% were found. There were six differences between MC and normal tissues, in which two proteins exhibited upregulated expression levels and four proteins exhibited downregulated expression levels in MC...
October 17, 2016: Oncology Reports
Hai-Long Liu, Yu-Jie Chang, Ting Fan, Zhi-Yuan Gu
Stable 2-D metal-organic framework nanosheets were utilized as a superior clean-background matrix for MALDI-TOF MS analysis of small biomolecules and pollutants in both positive and negative ion modes. The matrix could unusually afford up to 1000 mM of the salt concentrations in the monitoring of the enzymatic hydrolysis of neurotransmitter acetylcholine.
October 17, 2016: Chemical Communications: Chem Comm
Didrik Hjertaker Grevskott, Cecilie Smith Svanevik, Astrid Louise Wester, Bjørn Tore Lunestad
Continuous European Union programmes with specified methods for enumeration of Escherichia coli in bivalves for human consumption are currently running. The objective of this research was to examine the species accuracy of the five times three tube Most Probable Number (MPN) EU reference method used for detection of E. coli in marine bivalves. Among 549 samples of bivalves harvested from Norwegian localities during 2014 and 2015, a total number of 200 bacterial isolates were prepared from randomly selected culture-positive bivalves...
October 13, 2016: Journal of Microbiological Methods
M Mulet, M Gomila, A Ramírez, S Cardew, E R B Moore, J Lalucat, E García-Valdés
Fifty-two Pseudomonas strains that were difficult to identify at the species level in the phenotypic routine characterizations employed by clinical microbiology laboratories were selected for genotypic-based analysis. Species level identifications were done initially by partial sequencing of the DNA dependent RNA polymerase sub-unit D gene (rpoD). Two other gene sequences, for the small sub-unit ribosonal RNA (16S rRNA) and for DNA gyrase sub-unit B (gyrB) were added in a multilocus sequence analysis (MLSA) study to confirm the species identifications...
October 15, 2016: European Journal of Clinical Microbiology & Infectious Diseases
Alba Hykollari, Katharina Paschinger, Barbara Eckmair, Iain B H Wilson
N-glycans from invertebrates and protists have often unusual structures which present analytical challenges. Both core and antennal modifications can be quite different from the more familiar vertebrate glycan motifs; thereby, contrary to the concept that "simple" organisms have "simple" N-glycans, rather complex oligosaccharides structures, including zwitterionic and anionic ones, have been found in a range of species. Thus, to facilitate the optimized elucidation of the maximal possible range of structures, the analytical workflow for glycomics of these organisms should include sequential release and fractionation steps...
2017: Methods in Molecular Biology
Noortje de Haan, Karli R Reiding, Manfred Wuhrer
Matrix-assisted laser desorption/ionization (MALDI)-time-of-flight (TOF)-mass spectrometry (MS) is a highly suitable method for the rapid analysis of IgG glycopeptides, providing a wealth of structural information. A limitation of this approach is that it generates a bias when analyzing sialylated species due to the labile nature of sialic acid glycosidic linkages. One way to overcome this problem is by chemical derivatization of the sialic acids. The method presented here results in both the stabilization of the sialic acids, as well as the differentiation of α2,3- and α2,6-linked sialic acids by mass...
2017: Methods in Molecular Biology
Bin Qi, Shan Wang, Qiu Wang, He Zhang, Xue-Yuan Bai, Hui-Nan He, Wei-Jie Sun, Li Liu, Da-Qing Zhao
ETHNOPHARMACOLOGICAL RELEVANCE: Panax quinquefolius L. has been used as a proverbial tonic in oriental countries for hundreds of years. It is used as a traditional medicinal herb to nourish vitality. AIM OF THE STUDY: The purpose of our study was to inquiry the activation effects on murine peritoneal macrophages of a novel protein separated from the roots of Panax quinquefolius L. MATERIALS AND METHODS: In our work, a novel protein of the roots of American ginseng (AGNP) was separated and purified from the roots of Panax quinquefolius L...
October 11, 2016: Journal of Ethnopharmacology
Natalija Topić Popović, Snježana P Kazazić, Ivančica Strunjak-Perović, Rozelindra Čož-Rakovac
Identification of bacteria in aquatic and environmental applications, for monitoring purposes and research, for health assessments and therapy considerations of farmed and free-living aquatic organisms, still relies on conventional phenotypic and biochemical protocols. Although molecular techniques based on DNA amplification and sequencing are finding ways into diagnostic laboratories, they are time-consuming, costly and difficult in the case of multiplex assays. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) is a rapid and accurate proteomic method reliable for identification of unknown bacteria to the genus and species level...
October 11, 2016: Environmental Research
Yu Tokita, Masaru Katoh, Yoshihiro Ohta, Tsutomu Yokozawa
We have investigated the requirements for efficient Pd-catalyzed Suzuki-Miyaura catalyst-transfer condensation polymerization (Pd-CTCP) reactions of 2-alkoxypropyl-6-(5-bromothiophen-2-yl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (12) as a donor-acceptor (D-A) biaryl monomer. As model reactions, we first carried out the Suzuki-Miyaura coupling reaction of X-Py-Th-X' (Th=thiophene, Py=pyridine, X, X'=Br or I) 1 with phenylboronic acid ester 2 by using tBu3 PPd(0) as the catalyst. Monosubstitution with a phenyl group at Th-I mainly took place in the reaction of Br-Py-Th-I (1 b) with 2, whereas disubstitution selectively occurred in the reaction of I-Py-Th-Br (1 c) with 2, indicating that the Pd catalyst is intramolecularly transferred from acceptor Py to donor Th...
October 14, 2016: Chemistry: a European Journal
Rongpong Plongla, Theofano Panagea, David H Pincus, Melissa C Jones, Peter H Gilligan
Environmental glucose non-fermenting Gram-negative bacilli other than Pseudomonas aeruginosa are frequently isolated from respiratory specimens of patients with cystic fibrosis (CF) (1).….
October 12, 2016: Journal of Clinical Microbiology
A Veloso, J R Leiza
Cross-contamination from the polymeric material of the vial caps used in size exclusion chromatography (SEC) and high-performance liquid chromatography autosamplers in the low molar mass (LMM) range (<2000 Da) of polymer samples was demonstrated with the help of matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) analysis. It is shown that polyethylene (PE) caps, if exposed to either short or long periods in tetrahydrofuran solvent, might extract oligomers that contaminate the LMM end of the SEC chromatograms...
October 12, 2016: Journal of Chromatographic Science
Jari Intra, Roberta Maria Sala, Rosanna Falbo, Fabrizio Cappellini, Paolo Brambilla
Rapid and early identification of microorganisms in blood has a key role in the diagnosis of a febrile patient, in particular, in guiding the clinician to define the correct antibiotic therapy. This study presents a simple and very fast method with high performances for identifying bacteria by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) after only 4 hours of incubation. We used early bacterial growth on PolyViteX chocolate agar plates inoculated with 5 drops of blood-broth medium deposited in the same point and spread with a sterile loop, followed by a direct transfer procedure on MALDI-TOF MS target slides without additional modification...
October 12, 2016: Letters in Applied Microbiology
Cosima Damiana Calvano, Giovanni Ventura, Massimo Trotta, Giuliana Bianco, Tommaso R I Cataldi, Francesco Palmisano
Bacteriochlorophyll a (BChl a), a photosynthetic pigment performing the same functions of chlorophylls in plants, features a bacteriochlorin macrocycle ring (18 π electrons) with two reduced pyrrole rings along with a hydrophobic terpenoid side chain (i.e., the phytol residue). Chlorophylls analysis by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) is not so straightforward since pheophytinization (i.e., release of the central metal ion) and cleavage of the phytol-ester linkage are invariably observed by employing protonating matrices such as 2,5-dihydroxybenzoic acid, sinapinic acid, and α-cyano-4-hydroxycinnamic acid...
October 11, 2016: Journal of the American Society for Mass Spectrometry
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