An effective technique for the suppression of matrix-related ions in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry have been developed. Using typical organic matrices such as THAP (2,4,6-trihydroxyacetophenone) and CHCA (alpha-cyano-4-hydroxycinnamic acid) in a cyclodextrin cavity, we successfully measured the mass peaks of only protonated matrix ions and significantly s...

C-1 and C-6 hydroxylated bile acid metabolites in various biological specimens from subjects with liver disease (cholestasis, liver cirrhosis, chronic hepatitis, acute hepatitis) were determined by gas-liquid chromatography-mass spectrometry. Five C-1 hydroxylated bile acids and nine C-6 hydroxylated bile acids were identified in the urine studied; 1 beta,3 alpha,12 alpha-trihydroxy-, 1 beta,3 ...

Integrin alpha 3A cytoplasmic tail phosphorylation was mapped to amino acid S1042, as determined by mass spectrometry, and confirmed by mutagenesis. This residue occurs within a "QPSXXE" motif conserved in multiple alpha chains (alpha 3A, alpha 6A, alpha 7A), from multiple species. Phosphorylation of alpha 3A and alpha 6A did not appear to be directly mediated by protein kinase C (PKC) alpha, b...

Twenty different oligosaccharides have been isolated from urine collected from an A, Le(a- b+), secretor woman during her pregnancy and subsequent lactation. Nine of these have been found previously in the milk of Le (a- b+) individuals. Three new fucose-containing oligosaccharides denoted lacto-N-neotrifucoheptaose II (alpha-L-Fuc-(1 leads to 2)-beta-D-Gal-(1 leads to 4)-[alpha-L-Fuc-(1 leads ...

Alpha s1-, alpha s2-, beta- and kappa-caseins from Somali camels (Camelus dromedarius) were purified by acid precipitation at pH 4.4, crudely separated into an alpha-CN and a beta-CN fraction and further purified by reversed-phase HPLC. Fragments of tryptic digests were sequenced. Amino acid patterns obtained were used to screen a cDNA library constructed from mRNA from lactating udder tissue. ...

Two glycosphingolipids, GSL-1 and GSL-3, were isolated from Sphingomonas capsulata and studied by methylation analysis, laser desorption mass spectrometry, and 1H and 13C NMR spectroscopy, including two-dimensional 1H,1H COSY and heteronuclear 13C,1H COSY experiments. GSL-1 and GSL-3 differ in their carbohydrate part, their structures being alpha-D-GlcpA-(1-->1)-Cer and alpha-D-Galp-(1-->6)-alp...

The essential oil composition from the aerial parts of three Anacardiaceae growing in Bahía Blanca, Argentina was studied by gas chromatography and gas chromatography-mass spectrometry. The essential oils of S. longifolia and S. fasciculata have been studied for the first time. The major constituents were alpha-pinene (46.5%), beta-pinene (15.1%) and alpha-phellandrene (10.1%) for S. longifolia...

Secondary organic aerosol (SOA) formation from the photooxidation of an anthropogenic (1,3,5-trimethylbenzene) and a biogenic (alpha-pinene) precursor was investigated at the new PSI smog chamber. The chemistry of the gas phase was followed by proton transfer reaction mass spectrometry, while the aerosol chemistry was investigated with aerosol mass spectrometry, ion chromatography, laser desorp...

An N-linked glycosylation in a novel C-lectin protein from snake venom was observed by Edman degradation and liquid chromatography-electrospray mass spectrometry. The peptides obtained by trypsin cleavage were analyzed to confirm the amino acid sequence and Asn5 was found to be the N-glycosylation site. The result was further confirmed by N-glycosidase digestion. In addition, the protein and tr...

Cassava tubers suffer from postharvest physiological deterioration (PPD) which normally sets in within 72 hours of harvest. This study examines the role scopoletin and carotenoids onset or delay PPD two transgenic varieties EC20-7 EC20-8 compared to a wild variety TME-7. Scopoletin were quantified by liquid chromatography-mass spectrometry. The content (0.10 – 0.20 nmol/g) fresh was n...