Protein Sequence Culling Server

The Protein Sequence Culling Server (PISCES) is a database with a simple filter-and-download interface created to produce lists of sequences from the Protein Data Bank (PDB) using a number of entry- and chain-specific criteria and mutual sequence identity. The purpose of the database is to provide the longest list possible of the highest resolution structures that fulfil certain sequence identity and structural quality cut-offs. It uses a combination of PSI-BLAST and structure-based alignments to determine sequence identities. PISCES has two ways of producing subsets of sequences from larger sets: 1. Subsets of protein chains and sequences culled from the entire PDB according to structure quality and maximum mutual sequence identity, and 2. Subsets of protein chains and sequences culled from a list of PDB chains or PDB entries input by the user, according to structure quality and maximum mutual sequence identity蛋白质序列筛选服务器（Protein Sequence Culling Server，PISCES）是一款内置简洁筛选与下载界面的数据库，旨在依据多项条目与链特异性筛选标准及两两序列同一性阈值，从蛋白质数据银行（Protein Data Bank，PDB）中生成序列列表。该数据库的核心目标是，在满足特定序列同一性与结构质量截止阈值的前提下，提供尽可能长的高分辨率结构序列列表。该数据库结合使用PSI-BLAST与基于结构的比对方法来确定序列同一性。PISCES支持两种方式从更大的序列集合中生成序列子集：1. 依据结构质量与最大两两序列同一性阈值，从完整PDB数据库中筛选得到的蛋白质链与序列子集；2. 依据结构质量与最大两两序列同一性阈值，从用户输入的PDB链或PDB条目列表中筛选得到的蛋白质链与序列子集。

搜集汇总

背景与挑战

背景概述

PISCES是一个蛋白质序列筛选服务器，用于从蛋白质数据库（PDB）中根据结构质量和最大序列相似性标准生成高质量序列子集。它提供两种筛选模式：基于整个PDDB的自动筛选和基于用户自定义列表的筛选，并支持多种结构类型和质量评估选项。