Incremented alkyl derivatives enhance collision induced glycosidic bond cleavage in mass spectrometry of disaccharides

Incremented alkyl derivatives enhance collision induced glycosidic bond cleavage in mass spectrometry of disaccharides.

Electrospray ionization and collision induced dissociation on a triple quadrupole mass spectrometer were used to determine the effect of spatial crowding of incremented alkyl groups of two anomeric pairs of peralkylated (methyl to pentyl) disaccharides (maltose/cellobiose and isomaltose/gentiobiose). Protonated molecules were generated which underwent extensive fragmentation under low energy co...

Collision-induced liquid secondary-ion mass spectra of oxytocin derivatives. A study of the influence of modifications in the disulfide bond on the adjacent peptide bond cleavage.

The influence of the inductive effect of modifications in the disulfide bridge in oxytocin analogs on the cleavage of the neighboring peptidic bond was studied. A correlation between the inductive constant of the group in the disulfide bridge and the particular fragment ion abundance was observed.

Rapid identification of disaccharides by tandem mass spectrometry.

Cytotoxicity of alkyl-lysophospholipid derivatives and low-alkyl-cleavage enzyme activities in rat brain tumor cells.

Alkyl-lysophospholipids (ALP) and related derivatives inhibited the in vitro incorporation of [3H]thymidine into seven different permanent cell lines derived from rat brain tumors. The cytostatic effect of ALP was dependent on dosage and incubation time. Naturally occurring 2-lysophosphatidylcholine did not exhibit cytostatic effects; under these conditions, the incorporation rates of [3H]thymi...

Mechanisms for enzymatic cleavage of the N-glycosidic bond in DNA.

DNA glycosylases remove damaged or enzymatically modified nucleobases from DNA, thereby initiating the base excision repair (BER) pathway, which is found in all forms of life. These ubiquitous enzymes promote genomic integrity by initiating repair of mutagenic and/or cytotoxic lesions that arise continuously due to alkylation, deamination, or oxidation of the normal bases in DNA. Glycosylases a...