2DCSi利用核磁共振化學位移(NMR chemical shifts)，包含1Hα、1HN、13Cα、13C’、15NH等原子相對於13Cβ原子的二維叢集分析(2D cluster analyses)，來預測20種胺基酸的二級結構，與胱胺酸(Cysteine，Cys)的氧化還原態(redox states)。
我們從BioMagResBank (BMRB)資料庫提供的檔案中擷取每一個胺基酸的1Hα、1HN、13Cα、13C’、15NH、13Cβ原子的化學位移，建立計分矩陣(scoring matrix)，以此計分矩陣為基礎，使用者可利用我們架設之2DCSi伺服器，輸入胺基酸化學位移資料、或上傳BMRB檔案，來預測其二級結構與胱胺酸之氧化還原狀態。
2DCSi server網址：http://ncku.2dsci.idv.tw。

2DCSi predicts the secondary structures of 20 amino acids and the redox states of cysteine residues in proteins by using their NMR chemical shifts.
We use 2D cluster analyses of 1Hα, 1HN, 13Cα, 13C’, and 15NH versus 13Cβ NMR chemical shifts which were constructed from BioMagResBank (BMRB) entries. A database of 20 amino acids’ 1Hα, 1HN, 13Cα, 13C’, 15NH, and 13Cβ NMR chemical shifts were obtained and then used to produce the scoring matrices. Applying the prediction rules, the 2DCSi server enables users to submit NMR chemical shifts data and to request protein secondary structure assignments and the redox states of cysteine residues.
2DCSi server is available at http://ncku.2dsci.idv.tw.

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