Li Long, Kresh Joshua A, Karabacak N Murat, Cobb Jennifer S, Agar Jeffrey N, Hong Pengyu
Department of Chemistry and Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454, USA.
J Am Soc Mass Spectrom. 2008 Dec;19(12):1867-74. doi: 10.1016/j.jasms.2008.08.008. Epub 2008 Aug 15.
This article presents a memory efficient algorithm for accurately calculating the isotopic fine structures of molecules. Treating individual isotopic species of a molecule as different mass states, we introduce the concept of transitions between mass states and represent all mass states of the molecule in a hierarchical structure. We show that there exists a simple relationship between two different mass states at two different levels of the hierarchical structure. This allows us to efficiently and accurately compute both the mass and the abundance of every mass state of a small to medium-sized molecule, whose gross structures include small number of fine structures. A truncated calculation of this algorithm can be applied to calculate a majority of isotopic species (99.99% of cumulative abundance) of a large molecule.
本文提出了一种内存高效算法，用于精确计算分子的同位素精细结构。将分子的各个同位素种类视为不同的质量状态，我们引入了质量状态之间跃迁的概念，并以层次结构表示分子的所有质量状态。我们表明，在层次结构的两个不同级别上的两个不同质量状态之间存在简单关系。这使我们能够高效且准确地计算中小分子每个质量状态的质量和丰度，这些小分子的总体结构包含少量精细结构。该算法的截断计算可用于计算大分子的大多数同位素种类（累积丰度的99.99%）。
