示例#1
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def bioPython_default_local_aligner(a, b):
    aligner = PairwiseAligner()
    aligner.mode = 'local'
    aligner.match_score = 2
    aligner.mismatch_score = -3
    aligner.open_gap_score = -7
    aligner.extend_gap_score = -2

    sequence1 = SeqIO.read('./resource/fasta' + str(a) + '.fasta', 'fasta')
    sequence2 = SeqIO.read('./resource/fasta' + str(b) + '.fasta', 'fasta')
    alignments = aligner.align(sequence1.seq, sequence2.seq)
示例#2
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                    type=str,
                    required=True)

parser.add_argument('-r',
                    '--reference',
                    help='Reference to be aligned to',
                    type=str,
                    required=True)

parser.add_argument('-n',
                    '--seq_name',
                    help='Name of the aligned sequence',
                    type=str,
                    required=True)

args = parser.parse_args()

aligner = PairwiseAligner()
aligner.mode = 'global'
aligner.match_score = 1
aligner.mismatch_score = 0
aligner.open_gap_score = -2
aligner.extend_gap_score = -1

ref = SeqIO.read(args.reference, "fasta")
ref.seq = str(ref.seq.upper()).replace('-', 'N')
cons = SeqIO.read(args.infile, "fasta")
aln = aligner.align(ref.seq, cons.seq)
with open(args.outfile, 'w') as out:
    print(">", args.seq_name, file=out)
    print(str(aln[0]).strip().split('\n')[2], file=out)
示例#3
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parser = argparse.ArgumentParser(description='Computes a pairwise similarity matrix from a fasta file.')
parser.add_argument('-f',help='name of the fasta file',required=True)
parser.add_argument('-s',help='name of subsitution matrix from BioPython',required=True,choices=MatrixInfo.available_matrices)
parser.add_argument('-go',help='gap opening score',type=float,required=True)
parser.add_argument('-ge',help='gap extension score',type=float,required=True)
args = parser.parse_args()

# Parse fasta file #
seqs = list(SeqIO.parse(args.f,'fasta'))

# Get substitution matrix 
substitution_matrix = getattr(MatrixInfo,args.s)

#Pairwise alignment 
aligner = PairwiseAligner()
aligner.open_gap_score, aligner.extend_gap_score  = args.go, args.ge
aligner.substitution_matrix = substitution_matrix

# Align sequences and build matrix
def similarity_matrix(seqs,n=len(seqs)):
  similarity_matrix = np.zeros([n,n])
	for i in range(len(seqs)):
    for j in range(len(seqs)):
			alignment = aligner.align(seqs[i].seq,seqs[j].seq)
			similarity_matrix[i][j] = alignment.score
	return similarity_matrix

m = similarity_matrix(seqs)

def print_matrix(m):
	for i in m:
    aligners['global'].substitution_matrix = sub_matrix
    if not args.open_gap_score:
        args.open_gap_score = -11
    if not args.extend_gap_score:
        args.extend_gap_score = -1
aligners['global'].open_gap_score = args.open_gap_score
aligners['global'].extend_gap_score = args.extend_gap_score
if args.sim_algo == 'smith-waterman':
    aligners['local'] = PairwiseAligner()
    aligners['local'].mode = 'local'
    if args.seq_type in ('dna', 'rna'):
        aligners['local'].match = args.match_score
        aligners['local'].mismatch = args.mismatch_score
    else:
        aligners['local'].substitution_matrix = sub_matrix
    aligners['local'].open_gap_score = args.open_gap_score
    aligners['local'].extend_gap_score = args.extend_gap_score

# Karlin-Altschul parameter values
if args.seq_type in ('dna', 'rna'):
    if ((args.match_score, args.mismatch_score) in KA_PARAMS['na']
            and (abs(args.open_gap_score), abs(args.extend_gap_score))
            in KA_PARAMS['na'][(args.match_score, args.mismatch_score)]):
        args.ka_gapped_l = KA_PARAMS['na'][(args.match_score,
                                            args.mismatch_score)][(
                                                abs(args.open_gap_score),
                                                abs(args.extend_gap_score))][0]
        args.ka_gapped_k = KA_PARAMS['na'][(args.match_score,
                                            args.mismatch_score)][(
                                                abs(args.open_gap_score),
                                                abs(args.extend_gap_score))][1]