Applied Biosystems

About: Applied Biosystems is a based out in . It is known for research contribution in the topics: Mass spectrometry & Capillary electrophoresis. The organization has 1521 authors who have published 1579 publications receiving 285423 citations.

Imaging as a tool for improving length and accuracy of sequence analysis in automated fluorescence-based DNA sequencing.

Abstract: A new method of signal analysis for automated fluorescence-based DNA sequencing is presented. Signal resolution is a limiting factor in obtaining accurate sequence information beyond 400-450 nucleotides per gel lane. We have developed a computer program for the imaging of DNA bands in sequencing gels. The image analysis shows that distortions in the shapes of the bands decrease resolution of peaks observed served in the standard data plots. Reconstruction of the undistorted band shape prior to signal analysis substantially improves the resolution of peaks and may improve the accuracy and length of the contiguous sequence read. Image analysis identified other factors limiting the accuracy and length of automated DNA sequence analysis and provided a tool for evaluating various remedies. Our techniques should also be applicable in other systems, for example, in gel electrophoresis of proteins and DNA restriction fragments, and in scranning densitometry.

Method of mass analysis of target molecules in complex mixtures

Abstract: The present invention is a method for performing a mass spectrometric analysis of analytes in a complex mixture. In particular, samples containing unknown analytes are analyzed by MS/MS to identify portions of a molecule of interest that has been labeled with a selected isotope. Ionization and detection identify a characteristic isotope shift in real time based on a selective precursor ion scan that in turn identifies precursor masses that also contain the isotopic shift. From the precursor ion scan, precursor masses are identified for further mass spectrometric analyses. The method of the invention is preferably performed in real time such that the precursor ion scan simultaneously identifies target precursor ions and identifies precursor masses for further analyses.

Neuropeptide schistosomin inhibits hormonally-induced ovulation in the freshwater snail Lymnaea stagnalis.

Abstract: This study examines the interaction between the caudodorsal cell hormone (CDCH) and schistosomin, a peptide secreted by the central nervous system of the snail (Lymnaea stagnalis) infected with the avain schistosome Trichobilharzia ocellata. Non-infected snails were injected with synthetic as well as native CDCH in the absence or presence of purified schistosomin. The response to 2 pmol of synthetic CDCH was blocked for 90% by coinjection with 3.5 pmol of schistosomin. The ovulation-inducing activity of extracts of cerebral commissures (the storage area of native CDCH) was also blocked by schistosomin. The degree of inhibition (65%), however, was less than that observed with synthetic CDCH. These results show that schistosomin inhibits ovulation and egg laying in Lymnaea. This explains the decrease or absence of egg laying in schistosome-infected freshwater snails.