www.gusucode.com > bioinfo 案例源码程序 matlab代码 > bioinfo/CleaveASequenceExample.m
%% Cleave a sequence % This example shows how to cleave a sequence using trypsin. % Copyright 2015 The MathWorks, Inc. %% % Retrieve a protein sequence from the GenPept database. S = getgenpept('AAA59174'); %% % Cleave the sequence using trypsin's cleavage rules and all known % exceptions. parts = cleave(S.Sequence,'trypsin'); %% % Display the first ten fragments. parts(1:10) %% % Cleave the sequence using trypsin's cleavage rules and a single specific % exception rule. parts = cleave(S.Sequence,'trypsin','exception','KD'); parts(1:10) %% % Cleave the sequence using one of trypsin's cleavage rules, which is to % cleave after K or R when the next residue is not P. [parts, sites, lengths] = cleave(S.Sequence,'[KR](?!P)',1); for i = 1:10 fprintf('%5d%5d %s\n',sites(i),lengths(i),parts{i}) end %% % Cut the sequence using trypsin, allowing for 1 missed cleavage site. [parts2, sites2, lengths2, missed] = cleave(S.Sequence,'trypsin','missedsites',1); %% % Display the first 10 fragments that have 1 missed cleavage site. idx = find(missed); for i = 1:10 fprintf('%5d%5d %s\n',sites2(idx(i)),lengths2(idx(i)),parts2{idx(i)}) end