zoukankan      html  css  js  c++  java
  • Biopython

    Introduction

    From the biopython website their goal is to “make it as easy as possible to use Python for bioinformatics by creating high-quality, reusable modules and scripts.” These modules use the biopython tutorial as a template for what you will learn here.  Here is a list of some of the most common data formats in computational biology that are supported by biopython.

    UsesNote
    Blast finds regions of local similarity between sequences
    ClustalW multiple sequence alignment program
    GenBank NCBI sequence database
    PubMed and Medline Document database
    ExPASy SIB resource portal (Enzyme and Prosite)
    SCOP Structural Classification of Proteins (e.g. ‘dom’,’lin’)
    UniGene computationally identifies transcripts from the same locus
    SwissProt annotated and non-redundant protein sequence database

    Some of the other principal functions of biopython.

    • A standard sequence class that deals with sequences, ids on sequences, and sequence features.
    • Tools for performing common operations on sequences, such as translation, transcription and weight calculations.
    • Code to perform classification of data using k Nearest Neighbors, Naive Bayes or Support Vector Machines.
    • Code for dealing with alignments, including a standard way to create and deal with substitution matrices.
    • Code making it easy to split up parallelizable tasks into separate processes.
    • GUI-based programs to do basic sequence manipulations, translations, BLASTing, etc.

    Getting started

    >>> import Bio
    >>> Bio.__version__
    '1.58'
    

    Some examples will also require a working internet connection in order to run.

    >>> from Bio.Seq import Seq
    >>> my_seq = Seq("AGTACACTGGT")
    >>> my_seq
    Seq('AGTACACTGGT', Alphabet())
    >>> aStringSeq = str(my_seq)
    >>> aStringSeq
    'AGTACACTGGT'
    >>> my_seq_complement = my_seq.complement()
    >>> my_seq_complement
    Seq('TCATGTGACCA', Alphabet())
    >>> my_seq_reverse = my_seq.reverse()
    >>> my_seq_rc = my_seq.reverse_complement()
    >>> my_seq_rc
    Seq('ACCAGTGTACT', Alphabet())
    

    There is so much more, but first before we get into it we should figure out how to get sequences in and out of python.

    File download

    FASTA formats are the standard format for storing sequence data.  Here is a little reminder about sequences.

    Nucleic acid codeNoteNucleic acid codeNote
    A adenosine K G/T (keto)
    T thymidine M A/C (amino)
    C cytidine R G/A (purine)
    G guanine S G/C (strong)
    N A/G/C/T (any) W A/T (weak)
    U uridine B G/T/C
    D G/A/T Y T/C (pyrimidine)
    H A/C/T V G/C/A

    Here is quickly a bit about how biopython works with sequences

    >>> for seq_record in SeqIO.parse(os.path.join("data","ls_orchid.fasta"), "fasta"):
    ...     print seq_record.id
    ...     print repr(seq_record.seq)
    ...     print len(seq_record)
    ...
    gi|2765658|emb|Z78533.1|CIZ78533
    Seq('CGTAACAAGGTTTCCGTAGGTGAACCTGCGGAAGGATCATTGATGAGACCGTGG...CGC', SingleLetterAlphabet())
    740
    
  • 相关阅读:
    Linux系统学习之网络管理
    EntityFramework 6.1.2-beta2
    微软开源的30个基础设施项目-C#
    vs2015 Android SDK
    批量删除空的文件夹
    统一者管理员指南(Unifier Administration Guide)中文
    XXX全球 IP 地址库
    mssql2008R2 RCU-6083:ALTER database FWC SET READ_COMMITTED_SNAPSHOT ON
    ORA-01843: 无效的月份,执行sql语句更改为美国语言后仍然失败的解决办法
    Win7如何安装IIS来浏览ASP网站
  • 原文地址:https://www.cnblogs.com/pennyy/p/4119574.html
Copyright © 2011-2022 走看看