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# Copyright 2000 by Jeffrey Chang, Brad Chapman. All rights reserved.
# Copyright 2006-2011 by Peter Cock. All rights reserved.
# This code is part of the Biopython distribution and governed by its
# license. Please see the LICENSE file that should have been included
# as part of this package.
"""Code to work with GenBank formatted files.
Rather than using Bio.GenBank, you are now encouraged to use Bio.SeqIO with
the "genbank" or "embl" format names to parse GenBank or EMBL files into
SeqRecord and SeqFeature objects (see the Biopython tutorial for details).
Using Bio.GenBank directly to parse GenBank files is only useful if you want
to obtain GenBank-specific Record objects, which is a much closer
representation to the raw file contents that the SeqRecord alternative from
the FeatureParser (used in Bio.SeqIO).
To use the Bio.GenBank parser, there are two helper functions:
read Parse a handle containing a single GenBank record
as Bio.GenBank specific Record objects.
parse Iterate over a handle containing multiple GenBank
records as Bio.GenBank specific Record objects.
The following internal classes are not intended for direct use and may
be deprecated in a future release.
Classes:
Iterator Iterate through a file of GenBank entries
ErrorFeatureParser Catch errors caused during parsing.
FeatureParser Parse GenBank data in SeqRecord and SeqFeature objects.
RecordParser Parse GenBank data into a Record object.
Exceptions:
ParserFailureError Exception indicating a failure in the parser (ie.
scanner or consumer)
LocationParserError Exception indiciating a problem with the spark based
location parser.
"""
import re
# other Biopython stuff
from Bio import SeqFeature
# other Bio.GenBank stuff
from utils import FeatureValueCleaner
from Scanner import GenBankScanner
#Constants used to parse GenBank header lines
GENBANK_INDENT = 12
GENBANK_SPACER = " " * GENBANK_INDENT
#Constants for parsing GenBank feature lines
FEATURE_KEY_INDENT = 5
FEATURE_QUALIFIER_INDENT = 21
FEATURE_KEY_SPACER = " " * FEATURE_KEY_INDENT
FEATURE_QUALIFIER_SPACER = " " * FEATURE_QUALIFIER_INDENT
#Regular expresions for location parsing
_solo_location = r"[<>]?\d+"
_pair_location = r"[<>]?\d+\.\.[<>]?\d+"
_between_location = r"\d+\^\d+"
_within_position = r"\(\d+\.\d+\)"
_re_within_position = re.compile(_within_position)
_within_location = r"([<>]?\d+|%s)\.\.([<>]?\d+|%s)" \
% (_within_position,_within_position)
assert _re_within_position.match("(3.9)")
assert re.compile(_within_location).match("(3.9)..10")
assert re.compile(_within_location).match("26..(30.33)")
assert re.compile(_within_location).match("(13.19)..(20.28)")
_oneof_position = r"one\-of\(\d+(,\d+)+\)"
_re_oneof_position = re.compile(_oneof_position)
_oneof_location = r"([<>]?\d+|%s)\.\.([<>]?\d+|%s)" \
% (_oneof_position,_oneof_position)
assert _re_oneof_position.match("one-of(6,9)")
assert re.compile(_oneof_location).match("one-of(6,9)..101")
assert re.compile(_oneof_location).match("one-of(6,9)..one-of(101,104)")
assert re.compile(_oneof_location).match("6..one-of(101,104)")
assert not _re_oneof_position.match("one-of(3)")
assert _re_oneof_position.match("one-of(3,6)")
assert _re_oneof_position.match("one-of(3,6,9)")
_simple_location = r"\d+\.\.\d+"
_re_simple_location = re.compile(r"^%s$" % _simple_location)
_re_simple_compound = re.compile(r"^(join|order|bond)\(%s(,%s)*\)$" \
% (_simple_location, _simple_location))
_complex_location = r"([a-zA-z][a-zA-Z0-9_]*(\.[a-zA-Z0-9]+)?\:)?(%s|%s|%s|%s|%s)" \
% (_pair_location, _solo_location, _between_location,
_within_location, _oneof_location)
_re_complex_location = re.compile(r"^%s$" % _complex_location)
_possibly_complemented_complex_location = r"(%s|complement\(%s\))" \
% (_complex_location, _complex_location)
_re_complex_compound = re.compile(r"^(join|order|bond)\(%s(,%s)*\)$" \
% (_possibly_complemented_complex_location,
_possibly_complemented_complex_location))
assert _re_simple_location.match("104..160")
assert not _re_simple_location.match("68451760..68452073^68452074")
assert not _re_simple_location.match("<104..>160")
assert not _re_simple_location.match("104")
assert not _re_simple_location.match("<1")
assert not _re_simple_location.match(">99999")
assert not _re_simple_location.match("join(104..160,320..390,504..579)")
assert not _re_simple_compound.match("bond(12,63)")
assert _re_simple_compound.match("join(104..160,320..390,504..579)")
assert _re_simple_compound.match("order(1..69,1308..1465)")
assert not _re_simple_compound.match("order(1..69,1308..1465,1524)")
assert not _re_simple_compound.match("join(<1..442,992..1228,1524..>1983)")
assert not _re_simple_compound.match("join(<1..181,254..336,422..497,574..>590)")
assert not _re_simple_compound.match("join(1475..1577,2841..2986,3074..3193,3314..3481,4126..>4215)")
assert not _re_simple_compound.match("test(1..69,1308..1465)")
assert not _re_simple_compound.match("complement(1..69)")
assert not _re_simple_compound.match("(1..69)")
assert _re_complex_location.match("(3.9)..10")
assert _re_complex_location.match("26..(30.33)")
assert _re_complex_location.match("(13.19)..(20.28)")
assert _re_complex_location.match("41^42") #between
assert _re_complex_location.match("AL121804:41^42")
assert _re_complex_location.match("AL121804:41..610")
assert _re_complex_location.match("AL121804.2:41..610")
assert _re_complex_location.match("one-of(3,6)..101")
assert _re_complex_compound.match("join(153490..154269,AL121804.2:41..610,AL121804.2:672..1487)")
assert not _re_simple_compound.match("join(153490..154269,AL121804.2:41..610,AL121804.2:672..1487)")
assert _re_complex_compound.match("join(complement(69611..69724),139856..140650)")
#Trans-spliced example from NC_016406, note underscore in reference name:
assert _re_complex_location.match("NC_016402.1:6618..6676")
assert _re_complex_location.match("181647..181905")
assert _re_complex_compound.match("join(complement(149815..150200),complement(293787..295573),NC_016402.1:6618..6676,181647..181905)")
assert not _re_complex_location.match("join(complement(149815..150200),complement(293787..295573),NC_016402.1:6618..6676,181647..181905)")
assert not _re_simple_compound.match("join(complement(149815..150200),complement(293787..295573),NC_016402.1:6618..6676,181647..181905)")
assert not _re_complex_location.match("join(complement(149815..150200),complement(293787..295573),NC_016402.1:6618..6676,181647..181905)")
assert not _re_simple_location.match("join(complement(149815..150200),complement(293787..295573),NC_016402.1:6618..6676,181647..181905)")
def _pos(pos_str, offset=0):
"""Build a Position object (PRIVATE).
For an end position, leave offset as zero (default):
>>> _pos("5")
ExactPosition(5)
For a start position, set offset to minus one (for Python counting):
>>> _pos("5", -1)
ExactPosition(4)
This also covers fuzzy positions:
>>> p = _pos("<5")
>>> p
BeforePosition(5)
>>> print p
<5
>>> int(p)
5
>>> _pos(">5")
AfterPosition(5)
By default assumes an end position, so note the integer behaviour:
>>> p = _pos("one-of(5,8,11)")
>>> p
OneOfPosition(11, choices=[ExactPosition(5), ExactPosition(8), ExactPosition(11)])
>>> print p
one-of(5,8,11)
>>> int(p)
11
>>> _pos("(8.10)")
WithinPosition(10, left=8, right=10)
Fuzzy start positions:
>>> p = _pos("<5", -1)
>>> p
BeforePosition(4)
>>> print p
<4
>>> int(p)
4
Notice how the integer behaviour changes too!
>>> p = _pos("one-of(5,8,11)", -1)
>>> p
OneOfPosition(4, choices=[ExactPosition(4), ExactPosition(7), ExactPosition(10)])
>>> print(p)
one-of(4,7,10)
>>> int(p)
4
"""
if pos_str.startswith("<"):
return SeqFeature.BeforePosition(int(pos_str[1:])+offset)
elif pos_str.startswith(">"):
return SeqFeature.AfterPosition(int(pos_str[1:])+offset)
elif _re_within_position.match(pos_str):
s,e = pos_str[1:-1].split(".")
s = int(s) + offset
e = int(e) + offset
if offset == -1:
default = s
else:
default = e
return SeqFeature.WithinPosition(default, left=s, right=e)
elif _re_oneof_position.match(pos_str):
assert pos_str.startswith("one-of(")
assert pos_str[-1]==")"
parts = [SeqFeature.ExactPosition(int(pos)+offset) \
for pos in pos_str[7:-1].split(",")]
if offset == -1:
default = min(int(pos) for pos in parts)
else:
default = max(int(pos) for pos in parts)
return SeqFeature.OneOfPosition(default, choices=parts)
else:
return SeqFeature.ExactPosition(int(pos_str)+offset)
def _loc(loc_str, expected_seq_length, strand):
"""FeatureLocation from non-compound non-complement location (PRIVATE).
Simple examples,
>>> _loc("123..456", 1000, +1)
FeatureLocation(ExactPosition(122), ExactPosition(456), strand=1)
>>> _loc("<123..>456", 1000, strand = -1)
FeatureLocation(BeforePosition(122), AfterPosition(456), strand=-1)
A more complex location using within positions,
>>> _loc("(9.10)..(20.25)", 1000, 1)
FeatureLocation(WithinPosition(8, left=8, right=9), WithinPosition(25, left=20, right=25), strand=1)
Notice how that will act as though it has overall start 8 and end 25.
Zero length between feature,
>>> _loc("123^124", 1000, 0)
FeatureLocation(ExactPosition(123), ExactPosition(123), strand=0)
The expected sequence length is needed for a special case, a between
position at the start/end of a circular genome:
>>> _loc("1000^1", 1000, 1)
FeatureLocation(ExactPosition(1000), ExactPosition(1000), strand=1)
Apart from this special case, between positions P^Q must have P+1==Q,
>>> _loc("123^456", 1000, 1)
Traceback (most recent call last):
...
ValueError: Invalid between location '123^456'
"""
try:
s, e = loc_str.split("..")
except ValueError:
assert ".." not in loc_str
if "^" in loc_str:
#A between location like "67^68" (one based counting) is a
#special case (note it has zero length). In python slice
#notation this is 67:67, a zero length slice. See Bug 2622
#Further more, on a circular genome of length N you can have
#a location N^1 meaning the junction at the origin. See Bug 3098.
#NOTE - We can imagine between locations like "2^4", but this
#is just "3". Similarly, "2^5" is just "3..4"
s, e = loc_str.split("^")
if int(s)+1==int(e):
pos = _pos(s)
elif int(s)==expected_seq_length and e=="1":
pos = _pos(s)
else:
raise ValueError("Invalid between location %s" % repr(loc_str))
return SeqFeature.FeatureLocation(pos, pos, strand)
else:
#e.g. "123"
s = loc_str
e = loc_str
return SeqFeature.FeatureLocation(_pos(s,-1), _pos(e), strand)
def _split_compound_loc(compound_loc):
"""Split a tricky compound location string (PRIVATE).
>>> list(_split_compound_loc("123..145"))
['123..145']
>>> list(_split_compound_loc("123..145,200..209"))
['123..145', '200..209']
>>> list(_split_compound_loc("one-of(200,203)..300"))
['one-of(200,203)..300']
>>> list(_split_compound_loc("complement(123..145),200..209"))
['complement(123..145)', '200..209']
>>> list(_split_compound_loc("123..145,one-of(200,203)..209"))
['123..145', 'one-of(200,203)..209']
>>> list(_split_compound_loc("123..145,one-of(200,203)..one-of(209,211),300"))
['123..145', 'one-of(200,203)..one-of(209,211)', '300']
>>> list(_split_compound_loc("123..145,complement(one-of(200,203)..one-of(209,211)),300"))
['123..145', 'complement(one-of(200,203)..one-of(209,211))', '300']
>>> list(_split_compound_loc("123..145,200..one-of(209,211),300"))
['123..145', '200..one-of(209,211)', '300']
>>> list(_split_compound_loc("123..145,200..one-of(209,211)"))
['123..145', '200..one-of(209,211)']
>>> list(_split_compound_loc("complement(149815..150200),complement(293787..295573),NC_016402.1:6618..6676,181647..181905"))
['complement(149815..150200)', 'complement(293787..295573)', 'NC_016402.1:6618..6676', '181647..181905']
"""
if "one-of(" in compound_loc:
#Hard case
while "," in compound_loc:
assert compound_loc[0] != ","
assert compound_loc[0:2] != ".."
i = compound_loc.find(",")
part = compound_loc[:i]
compound_loc = compound_loc[i:] #includes the comma
while part.count("(") > part.count(")"):
assert "one-of(" in part, (part, compound_loc)
i = compound_loc.find(")")
part += compound_loc[:i+1]
compound_loc = compound_loc[i+1:]
if compound_loc.startswith(".."):
i = compound_loc.find(",")
if i==-1:
part += compound_loc
compound_loc = ""
else:
part += compound_loc[:i]
compound_loc = compound_loc[i:] #includes the comma
while part.count("(") > part.count(")"):
assert part.count("one-of(") == 2
i = compound_loc.find(")")
part += compound_loc[:i+1]
compound_loc = compound_loc[i+1:]
if compound_loc.startswith(","):
compound_loc = compound_loc[1:]
assert part
yield part
if compound_loc:
yield compound_loc
else:
#Easy case
for part in compound_loc.split(","):
yield part
class Iterator(object):
"""Iterator interface to move over a file of GenBank entries one at a time (OBSOLETE).
This class is likely to be deprecated in a future release of Biopython.
Please use Bio.SeqIO.parse(..., format="gb") or Bio.GenBank.parse(...)
for SeqRecord and GenBank specific Record objects respectively instead.
"""
def __init__(self, handle, parser = None):
"""Initialize the iterator.
Arguments:
o handle - A handle with GenBank entries to iterate through.
o parser - An optional parser to pass the entries through before
returning them. If None, then the raw entry will be returned.
"""
self.handle = handle
self._parser = parser
def next(self):
"""Return the next GenBank record from the handle.
Will return None if we ran out of records.
"""
if self._parser is None:
lines = []
while True:
line = self.handle.readline()
if not line : return None #Premature end of file?
lines.append(line)
if line.rstrip() == "//" : break
return "".join(lines)
try:
return self._parser.parse(self.handle)
except StopIteration:
return None
def __iter__(self):
return iter(self.next, None)
class ParserFailureError(Exception):
"""Failure caused by some kind of problem in the parser.
"""
pass
class LocationParserError(Exception):
"""Could not Properly parse out a location from a GenBank file.
"""
pass
class FeatureParser(object):
"""Parse GenBank files into Seq + Feature objects (OBSOLETE).
Direct use of this class is discouraged, and may be deprecated in
a future release of Biopython.
Please use Bio.SeqIO.parse(...) or Bio.SeqIO.read(...) instead.
"""
def __init__(self, debug_level = 0, use_fuzziness = 1,
feature_cleaner = FeatureValueCleaner()):
"""Initialize a GenBank parser and Feature consumer.
Arguments:
o debug_level - An optional argument that species the amount of
debugging information the parser should spit out. By default we have
no debugging info (the fastest way to do things), but if you want
you can set this as high as two and see exactly where a parse fails.
o use_fuzziness - Specify whether or not to use fuzzy representations.
The default is 1 (use fuzziness).
o feature_cleaner - A class which will be used to clean out the
values of features. This class must implement the function
clean_value. GenBank.utils has a "standard" cleaner class, which
is used by default.
"""
self._scanner = GenBankScanner(debug_level)
self.use_fuzziness = use_fuzziness
self._cleaner = feature_cleaner
def parse(self, handle):
"""Parse the specified handle.
"""
self._consumer = _FeatureConsumer(self.use_fuzziness,
self._cleaner)
self._scanner.feed(handle, self._consumer)
return self._consumer.data
class RecordParser(object):
"""Parse GenBank files into Record objects (OBSOLETE).
Direct use of this class is discouraged, and may be deprecated in
a future release of Biopython.
Please use the Bio.GenBank.parse(...) or Bio.GenBank.read(...) functions
instead.
"""
def __init__(self, debug_level = 0):
"""Initialize the parser.
Arguments:
o debug_level - An optional argument that species the amount of
debugging information the parser should spit out. By default we have
no debugging info (the fastest way to do things), but if you want
you can set this as high as two and see exactly where a parse fails.
"""
self._scanner = GenBankScanner(debug_level)
def parse(self, handle):
"""Parse the specified handle into a GenBank record.
"""
self._consumer = _RecordConsumer()
self._scanner.feed(handle, self._consumer)
return self._consumer.data
class _BaseGenBankConsumer(object):
"""Abstract GenBank consumer providing useful general functions (PRIVATE).
This just helps to eliminate some duplication in things that most
GenBank consumers want to do.
"""
# Special keys in GenBank records that we should remove spaces from
# For instance, \translation keys have values which are proteins and
# should have spaces and newlines removed from them. This class
# attribute gives us more control over specific formatting problems.
remove_space_keys = ["translation"]
def __init__(self):
pass
def _unhandled(self, data):
pass
def __getattr__(self, attr):
return self._unhandled
def _split_keywords(self, keyword_string):
"""Split a string of keywords into a nice clean list.
"""
# process the keywords into a python list
if keyword_string == "" or keyword_string == ".":
keywords = ""
elif keyword_string[-1] == '.':
keywords = keyword_string[:-1]
else:
keywords = keyword_string
keyword_list = keywords.split(';')
clean_keyword_list = [x.strip() for x in keyword_list]
return clean_keyword_list
def _split_accessions(self, accession_string):
"""Split a string of accession numbers into a list.
"""
# first replace all line feeds with spaces
# Also, EMBL style accessions are split with ';'
accession = accession_string.replace("\n", " ").replace(";"," ")
return [x.strip() for x in accession.split() if x.strip()]
def _split_taxonomy(self, taxonomy_string):
"""Split a string with taxonomy info into a list.
"""
if not taxonomy_string or taxonomy_string==".":
#Missing data, no taxonomy
return []
if taxonomy_string[-1] == '.':
tax_info = taxonomy_string[:-1]
else:
tax_info = taxonomy_string
tax_list = tax_info.split(';')
new_tax_list = []
for tax_item in tax_list:
new_items = tax_item.split("\n")
new_tax_list.extend(new_items)
while '' in new_tax_list:
new_tax_list.remove('')
clean_tax_list = [x.strip() for x in new_tax_list]
return clean_tax_list
def _clean_location(self, location_string):
"""Clean whitespace out of a location string.
The location parser isn't a fan of whitespace, so we clean it out
before feeding it into the parser.
"""
#Originally this imported string.whitespace and did a replace
#via a loop. It's simpler to just split on whitespace and rejoin
#the string - and this avoids importing string too. See Bug 2684.
return ''.join(location_string.split())
def _remove_newlines(self, text):
"""Remove any newlines in the passed text, returning the new string.
"""
# get rid of newlines in the qualifier value
newlines = ["\n", "\r"]
for ws in newlines:
text = text.replace(ws, "")
return text
def _normalize_spaces(self, text):
"""Replace multiple spaces in the passed text with single spaces.
"""
# get rid of excessive spaces
text_parts = text.split(" ")
text_parts = filter(None, text_parts)
return ' '.join(text_parts)
def _remove_spaces(self, text):
"""Remove all spaces from the passed text.
"""
return text.replace(" ", "")
def _convert_to_python_numbers(self, start, end):
"""Convert a start and end range to python notation.
In GenBank, starts and ends are defined in "biological" coordinates,
where 1 is the first base and [i, j] means to include both i and j.
In python, 0 is the first base and [i, j] means to include i, but
not j.
So, to convert "biological" to python coordinates, we need to
subtract 1 from the start, and leave the end and things should
be converted happily.
"""
new_start = start - 1
new_end = end
return new_start, new_end
class _FeatureConsumer(_BaseGenBankConsumer):
"""Create a SeqRecord object with Features to return (PRIVATE).
Attributes:
o use_fuzziness - specify whether or not to parse with fuzziness in
feature locations.
o feature_cleaner - a class that will be used to provide specialized
cleaning-up of feature values.
"""
def __init__(self, use_fuzziness, feature_cleaner = None):
from Bio.SeqRecord import SeqRecord
_BaseGenBankConsumer.__init__(self)
self.data = SeqRecord(None, id = None)
self.data.id = None
self.data.description = ""
self._use_fuzziness = use_fuzziness
self._feature_cleaner = feature_cleaner
self._seq_type = ''
self._seq_data = []
self._cur_reference = None
self._cur_feature = None
self._expected_size = None
def locus(self, locus_name):
"""Set the locus name is set as the name of the Sequence.
"""
self.data.name = locus_name
def size(self, content):
"""Record the sequence length."""
self._expected_size = int(content)
def residue_type(self, type):
"""Record the sequence type so we can choose an appropriate alphabet.
"""
self._seq_type = type
def data_file_division(self, division):
self.data.annotations['data_file_division'] = division
def date(self, submit_date):
self.data.annotations['date'] = submit_date
def definition(self, definition):
"""Set the definition as the description of the sequence.
"""
if self.data.description:
#Append to any existing description
#e.g. EMBL files with two DE lines.
self.data.description += " " + definition
else:
self.data.description = definition
def accession(self, acc_num):
"""Set the accession number as the id of the sequence.
If we have multiple accession numbers, the first one passed is
used.
"""
new_acc_nums = self._split_accessions(acc_num)
#Also record them ALL in the annotations
try:
#On the off chance there was more than one accession line:
for acc in new_acc_nums:
#Prevent repeat entries
if acc not in self.data.annotations['accessions']:
self.data.annotations['accessions'].append(acc)
except KeyError:
self.data.annotations['accessions'] = new_acc_nums
# if we haven't set the id information yet, add the first acc num
if not self.data.id:
if len(new_acc_nums) > 0:
#self.data.id = new_acc_nums[0]
#Use the FIRST accession as the ID, not the first on this line!
self.data.id = self.data.annotations['accessions'][0]
def wgs(self, content):
self.data.annotations['wgs'] = content.split('-')
def add_wgs_scafld(self, content):
self.data.annotations.setdefault('wgs_scafld',[]).append(content.split('-'))
def nid(self, content):
self.data.annotations['nid'] = content
def pid(self, content):
self.data.annotations['pid'] = content
def version(self, version_id):
#Want to use the versioned accession as the record.id
#This comes from the VERSION line in GenBank files, or the
#obsolete SV line in EMBL. For the new EMBL files we need
#both the version suffix from the ID line and the accession
#from the AC line.
if version_id.count(".")==1 and version_id.split(".")[1].isdigit():
self.accession(version_id.split(".")[0])
self.version_suffix(version_id.split(".")[1])
elif version_id:
#For backwards compatibility...
self.data.id = version_id
def project(self, content):
"""Handle the information from the PROJECT line as a list of projects.
e.g.
PROJECT GenomeProject:28471
or:
PROJECT GenomeProject:13543 GenomeProject:99999
This is stored as dbxrefs in the SeqRecord to be consistent with the
projected switch of this line to DBLINK in future GenBank versions.
Note the NCBI plan to replace "GenomeProject:28471" with the shorter
"Project:28471" as part of this transition.
"""
content = content.replace("GenomeProject:", "Project:")
self.data.dbxrefs.extend([p for p in content.split() if p])
def dblink(self, content):
"""Store DBLINK cross references as dbxrefs in our record object.
This line type is expected to replace the PROJECT line in 2009. e.g.
During transition:
PROJECT GenomeProject:28471
DBLINK Project:28471
Trace Assembly Archive:123456
Once the project line is dropped:
DBLINK Project:28471
Trace Assembly Archive:123456
Note GenomeProject -> Project.
We'll have to see some real examples to be sure, but based on the
above example we can expect one reference per line.
Note that at some point the NCBI have included an extra space, e.g.
DBLINK Project: 28471
"""
#During the transition period with both PROJECT and DBLINK lines,
#we don't want to add the same cross reference twice.
while ": " in content:
content = content.replace(": ", ":")
if content.strip() not in self.data.dbxrefs:
self.data.dbxrefs.append(content.strip())
def version_suffix(self, version):
"""Set the version to overwrite the id.
Since the verison provides the same information as the accession
number, plus some extra info, we set this as the id if we have
a version.
"""
#e.g. GenBank line:
#VERSION U49845.1 GI:1293613
#or the obsolete EMBL line:
#SV U49845.1
#Scanner calls consumer.version("U49845.1")
#which then calls consumer.version_suffix(1)
#
#e.g. EMBL new line:
#ID X56734; SV 1; linear; mRNA; STD; PLN; 1859 BP.
#Scanner calls consumer.version_suffix(1)
assert version.isdigit()
self.data.annotations['sequence_version'] = int(version)
def db_source(self, content):
self.data.annotations['db_source'] = content.rstrip()
def gi(self, content):
self.data.annotations['gi'] = content
def keywords(self, content):
self.data.annotations['keywords'] = self._split_keywords(content)
def segment(self, content):
self.data.annotations['segment'] = content
def source(self, content):
#Note that some software (e.g. VectorNTI) may produce an empty
#source (rather than using a dot/period as might be expected).
if content == "":
source_info = ""
elif content[-1] == '.':
source_info = content[:-1]
else:
source_info = content
self.data.annotations['source'] = source_info
def organism(self, content):
self.data.annotations['organism'] = content
def taxonomy(self, content):
"""Records (another line of) the taxonomy lineage.
"""
lineage = self._split_taxonomy(content)
try:
self.data.annotations['taxonomy'].extend(lineage)
except KeyError:
self.data.annotations['taxonomy'] = lineage
def reference_num(self, content):
"""Signal the beginning of a new reference object.
"""
# if we have a current reference that hasn't been added to
# the list of references, add it.
if self._cur_reference is not None:
self.data.annotations['references'].append(self._cur_reference)
else:
self.data.annotations['references'] = []
self._cur_reference = SeqFeature.Reference()
def reference_bases(self, content):
"""Attempt to determine the sequence region the reference entails.
Possible types of information we may have to deal with:
(bases 1 to 86436)
(sites)
(bases 1 to 105654; 110423 to 111122)
1 (residues 1 to 182)
"""
# first remove the parentheses or other junk
ref_base_info = content[1:-1]
all_locations = []
# parse if we've got 'bases' and 'to'
if 'bases' in ref_base_info and 'to' in ref_base_info:
# get rid of the beginning 'bases'
ref_base_info = ref_base_info[5:]
locations = self._split_reference_locations(ref_base_info)
all_locations.extend(locations)
elif 'residues' in ref_base_info and 'to' in ref_base_info:
residues_start = ref_base_info.find("residues")
# get only the information after "residues"
ref_base_info = ref_base_info[(residues_start + len("residues ")):]
locations = self._split_reference_locations(ref_base_info)
all_locations.extend(locations)
# make sure if we are not finding information then we have
# the string 'sites' or the string 'bases'
elif (ref_base_info == 'sites' or
ref_base_info.strip() == 'bases'):
pass
# otherwise raise an error
else:
raise ValueError("Could not parse base info %s in record %s" %
(ref_base_info, self.data.id))
self._cur_reference.location = all_locations
def _split_reference_locations(self, location_string):
"""Get reference locations out of a string of reference information
The passed string should be of the form:
1 to 20; 20 to 100
This splits the information out and returns a list of location objects
based on the reference locations.
"""
# split possibly multiple locations using the ';'
all_base_info = location_string.split(';')
new_locations = []
for base_info in all_base_info:
start, end = base_info.split('to')
new_start, new_end = \
self._convert_to_python_numbers(int(start.strip()),
int(end.strip()))
this_location = SeqFeature.FeatureLocation(new_start, new_end)
new_locations.append(this_location)
return new_locations
def authors(self, content):
if self._cur_reference.authors:
self._cur_reference.authors += ' ' + content
else:
self._cur_reference.authors = content
def consrtm(self, content):
if self._cur_reference.consrtm:
self._cur_reference.consrtm += ' ' + content
else:
self._cur_reference.consrtm = content
def title(self, content):
if self._cur_reference is None:
import warnings
from Bio import BiopythonParserWarning
warnings.warn("GenBank TITLE line without REFERENCE line.",
BiopythonParserWarning)
elif self._cur_reference.title:
self._cur_reference.title += ' ' + content
else:
self._cur_reference.title = content
def journal(self, content):
if self._cur_reference.journal:
self._cur_reference.journal += ' ' + content
else:
self._cur_reference.journal = content
def medline_id(self, content):
self._cur_reference.medline_id = content
def pubmed_id(self, content):
self._cur_reference.pubmed_id = content
def remark(self, content):
"""Deal with a reference comment."""
if self._cur_reference.comment:
self._cur_reference.comment += ' ' + content
else:
self._cur_reference.comment = content
def comment(self, content):
try:
self.data.annotations['comment'] += "\n" + "\n".join(content)
except KeyError:
self.data.annotations['comment'] = "\n".join(content)
def features_line(self, content):
"""Get ready for the feature table when we reach the FEATURE line.
"""
self.start_feature_table()
def start_feature_table(self):
"""Indicate we've got to the start of the feature table.
"""
# make sure we've added on our last reference object
if self._cur_reference is not None:
self.data.annotations['references'].append(self._cur_reference)
self._cur_reference = None
def feature_key(self, content):
# start a new feature
self._cur_feature = SeqFeature.SeqFeature()
self._cur_feature.type = content
self.data.features.append(self._cur_feature)
def location(self, content):
"""Parse out location information from the location string.
This uses simple Python code with some regular expressions to do the
parsing, and then translates the results into appropriate objects.
"""
# clean up newlines and other whitespace inside the location before
# parsing - locations should have no whitespace whatsoever
location_line = self._clean_location(content)
# Older records have junk like replace(266,"c") in the
# location line. Newer records just replace this with
# the number 266 and have the information in a more reasonable
# place. So we'll just grab out the number and feed this to the
# parser. We shouldn't really be losing any info this way.
if 'replace' in location_line:
comma_pos = location_line.find(',')
location_line = location_line[8:comma_pos]
cur_feature = self._cur_feature
#Handle top level complement here for speed
if location_line.startswith("complement("):
assert location_line.endswith(")")
location_line = location_line[11:-1]
strand = -1
elif 'DNA' in self._seq_type.upper() or 'RNA' in self._seq_type.upper():
#Nucleotide
strand = 1
else:
#Protein
strand = None
#Special case handling of the most common cases for speed
if _re_simple_location.match(location_line):
#e.g. "123..456"
s, e = location_line.split("..")
cur_feature.location = SeqFeature.FeatureLocation(int(s)-1,
int(e),
strand)
return
if _re_simple_compound.match(location_line):
#e.g. join(<123..456,480..>500)
i = location_line.find("(")
cur_feature.location_operator = location_line[:i]
#we can split on the comma because these are simple locations
for part in location_line[i+1:-1].split(","):
s, e = part.split("..")
f = SeqFeature.SeqFeature(SeqFeature.FeatureLocation(int(s)-1,
int(e),
strand),
location_operator=cur_feature.location_operator,
type=cur_feature.type)
cur_feature.sub_features.append(f)
s = cur_feature.sub_features[0].location.start
e = cur_feature.sub_features[-1].location.end
cur_feature.location = SeqFeature.FeatureLocation(s,e, strand)
return
#Handle the general case with more complex regular expressions
if _re_complex_location.match(location_line):
#e.g. "AL121804.2:41..610"
if ":" in location_line:
location_ref, location_line = location_line.split(":")
cur_feature.location = _loc(location_line, self._expected_size, strand)
cur_feature.location.ref = location_ref
else:
cur_feature.location = _loc(location_line, self._expected_size, strand)
return
if _re_complex_compound.match(location_line):
i = location_line.find("(")
cur_feature.location_operator = location_line[:i]
#Can't split on the comma because of positions like one-of(1,2,3)
for part in _split_compound_loc(location_line[i+1:-1]):
if part.startswith("complement("):
assert part[-1]==")"
part = part[11:-1]
assert strand != -1, "Double complement?"
part_strand = -1
else:
part_strand = strand
if ":" in part:
ref, part = part.split(":")
else:
ref = None
try:
loc = _loc(part, self._expected_size, part_strand)
except ValueError, err:
print location_line
print part
raise err
f = SeqFeature.SeqFeature(location=loc, ref=ref,
location_operator=cur_feature.location_operator,
type=cur_feature.type)
cur_feature.sub_features.append(f)
# Historically a join on the reverse strand has been represented
# in Biopython with both the parent SeqFeature and its children
# (the exons for a CDS) all given a strand of -1. Likewise, for
# a join feature on the forward strand they all have strand +1.
# However, we must also consider evil mixed strand examples like
# this, join(complement(69611..69724),139856..140087,140625..140650)
strands = set(sf.strand for sf in cur_feature.sub_features)
if len(strands)==1:
strand = cur_feature.sub_features[0].strand
else:
strand = None # i.e. mixed strands
s = cur_feature.sub_features[0].location.start
e = cur_feature.sub_features[-1].location.end
cur_feature.location = SeqFeature.FeatureLocation(s, e, strand)
return
#Not recognised
if "order" in location_line and "join" in location_line:
#See Bug 3197
msg = 'Combinations of "join" and "order" within the same ' + \
'location (nested operators) are illegal:\n' + location_line
raise LocationParserError(msg)
#This used to be an error....
cur_feature.location = None
import warnings
from Bio import BiopythonParserWarning
warnings.warn(BiopythonParserWarning("Couldn't parse feature location: %r" \
% (location_line)))
def feature_qualifier(self, key, value):
"""When we get a qualifier key and its value.
Can receive None, since you can have valueless keys such as /pseudo
"""
# Hack to try to preserve historical behaviour of /pseudo etc
if value is None:
if key not in self._cur_feature.qualifiers:
self._cur_feature.qualifiers[key] = [""]
return
value = value.replace('"', '')
if self._feature_cleaner is not None:
value = self._feature_cleaner.clean_value(key, value)
# if the qualifier name exists, append the value
if key in self._cur_feature.qualifiers:
self._cur_feature.qualifiers[key].append(value)
# otherwise start a new list of the key with its values
else:
self._cur_feature.qualifiers[key] = [value]
def feature_qualifier_name(self, content_list):
"""Use feature_qualifier instead (OBSOLETE)."""
raise NotImplementedError("Use the feature_qualifier method instead.")
def feature_qualifier_description(self, content):
"""Use feature_qualifier instead (OBSOLETE)."""
raise NotImplementedError("Use the feature_qualifier method instead.")
def contig_location(self, content):
"""Deal with CONTIG information."""
#Historically this was stored as a SeqFeature object, but it was
#stored under record.annotations["contig"] and not under
#record.features with the other SeqFeature objects.
#
#The CONTIG location line can include additional tokens like
#Gap(), Gap(100) or Gap(unk100) which are not used in the feature
#location lines, so storing it using SeqFeature based location
#objects is difficult.
#
#We now store this a string, which means for BioSQL we are now in
#much better agreement with how BioPerl records the CONTIG line
#in the database.
#
#NOTE - This code assumes the scanner will return all the CONTIG
#lines already combined into one long string!
self.data.annotations["contig"] = content
def origin_name(self, content):
pass
def base_count(self, content):
pass
def base_number(self, content):
pass
def sequence(self, content):
"""Add up sequence information as we get it.
To try and make things speedier, this puts all of the strings
into a list of strings, and then uses string.join later to put
them together. Supposedly, this is a big time savings
"""
assert ' ' not in content
self._seq_data.append(content.upper())
def record_end(self, content):
"""Clean up when we've finished the record.
"""
from Bio import Alphabet
from Bio.Alphabet import IUPAC
from Bio.Seq import Seq, UnknownSeq
#Try and append the version number to the accession for the full id
if not self.data.id:
assert 'accessions' not in self.data.annotations, \
self.data.annotations['accessions']
self.data.id = self.data.name #Good fall back?
elif self.data.id.count('.') == 0:
try:
self.data.id+='.%i' % self.data.annotations['sequence_version']
except KeyError:
pass
# add the sequence information
# first, determine the alphabet
# we default to an generic alphabet if we don't have a
# seq type or have strange sequence information.
seq_alphabet = Alphabet.generic_alphabet
# now set the sequence
sequence = "".join(self._seq_data)
if self._expected_size is not None \
and len(sequence) != 0 \
and self._expected_size != len(sequence):
import warnings
from Bio import BiopythonParserWarning
warnings.warn("Expected sequence length %i, found %i (%s)." \
% (self._expected_size, len(sequence), self.data.id),
BiopythonParserWarning)
if self._seq_type:
# mRNA is really also DNA, since it is actually cDNA
if 'DNA' in self._seq_type.upper() or 'MRNA' in self._seq_type.upper():
seq_alphabet = IUPAC.ambiguous_dna
# are there ever really RNA sequences in GenBank?
elif 'RNA' in self._seq_type.upper():
#Even for data which was from RNA, the sequence string
#is usually given as DNA (T not U). Bug 2408
if "T" in sequence and "U" not in sequence:
seq_alphabet = IUPAC.ambiguous_dna
else:
seq_alphabet = IUPAC.ambiguous_rna
elif 'PROTEIN' in self._seq_type.upper():
seq_alphabet = IUPAC.protein # or extended protein?
# work around ugly GenBank records which have circular or
# linear but no indication of sequence type
elif self._seq_type in ["circular", "linear", "unspecified"]:
pass
# we have a bug if we get here
else:
raise ValueError("Could not determine alphabet for seq_type %s"
% self._seq_type)
if not sequence and self.__expected_size:
self.data.seq = UnknownSeq(self._expected_size, seq_alphabet)
else:
self.data.seq = Seq(sequence, seq_alphabet)
class _RecordConsumer(_BaseGenBankConsumer):
"""Create a GenBank Record object from scanner generated information (PRIVATE).
"""
def __init__(self):
_BaseGenBankConsumer.__init__(self)
import Record
self.data = Record.Record()
self._seq_data = []
self._cur_reference = None
self._cur_feature = None
self._cur_qualifier = None
def wgs(self, content):
self.data.wgs = content.split('-')
def add_wgs_scafld(self, content):
self.data.wgs_scafld.append(content.split('-'))
def locus(self, content):
self.data.locus = content
def size(self, content):
self.data.size = content
def residue_type(self, content):
# Be lenient about parsing, but technically lowercase residue types are malformed.
if 'dna' in content or 'rna' in content:
import warnings
from Bio import BiopythonParserWarning
warnings.warn("Invalid seq_type (%s): DNA/RNA should be uppercase." % content,
BiopythonParserWarning)
self.data.residue_type = content
def data_file_division(self, content):
self.data.data_file_division = content
def date(self, content):
self.data.date = content
def definition(self, content):
self.data.definition = content
def accession(self, content):
for acc in self._split_accessions(content):
if acc not in self.data.accession:
self.data.accession.append(acc)
def nid(self, content):
self.data.nid = content
def pid(self, content):
self.data.pid = content
def version(self, content):
self.data.version = content
def db_source(self, content):
self.data.db_source = content.rstrip()
def gi(self, content):
self.data.gi = content
def keywords(self, content):
self.data.keywords = self._split_keywords(content)
def project(self, content):
self.data.projects.extend([p for p in content.split() if p])
def dblink(self, content):
self.data.dblinks.append(content)
def segment(self, content):
self.data.segment = content
def source(self, content):
self.data.source = content
def organism(self, content):
self.data.organism = content
def taxonomy(self, content):
self.data.taxonomy = self._split_taxonomy(content)
def reference_num(self, content):
"""Grab the reference number and signal the start of a new reference.
"""
# check if we have a reference to add
if self._cur_reference is not None:
self.data.references.append(self._cur_reference)
import Record
self._cur_reference = Record.Reference()
self._cur_reference.number = content
def reference_bases(self, content):
self._cur_reference.bases = content
def authors(self, content):
self._cur_reference.authors = content
def consrtm(self, content):
self._cur_reference.consrtm = content
def title(self, content):
if self._cur_reference is None:
import warnings
from Bio import BiopythonParserWarning
warnings.warn("GenBank TITLE line without REFERENCE line.",
BiopythonParserWarning)
return
self._cur_reference.title = content
def journal(self, content):
self._cur_reference.journal = content
def medline_id(self, content):
self._cur_reference.medline_id = content
def pubmed_id(self, content):
self._cur_reference.pubmed_id = content
def remark(self, content):
self._cur_reference.remark = content
def comment(self, content):
self.data.comment += "\n".join(content)
def primary_ref_line(self,content):
"""Data for the PRIMARY line"""
self.data.primary.append(content)
def primary(self,content):
pass
def features_line(self, content):
"""Get ready for the feature table when we reach the FEATURE line.
"""
self.start_feature_table()
def start_feature_table(self):
"""Signal the start of the feature table.
"""
# we need to add on the last reference
if self._cur_reference is not None:
self.data.references.append(self._cur_reference)
def feature_key(self, content):
"""Grab the key of the feature and signal the start of a new feature.
"""
# first add on feature information if we've got any
self._add_feature()
import Record
self._cur_feature = Record.Feature()
self._cur_feature.key = content
def _add_feature(self):
"""Utility function to add a feature to the Record.
This does all of the appropriate checking to make sure we haven't
left any info behind, and that we are only adding info if it
exists.
"""
if self._cur_feature is not None:
# if we have a left over qualifier, add it to the qualifiers
# on the current feature
if self._cur_qualifier is not None:
self._cur_feature.qualifiers.append(self._cur_qualifier)
self._cur_qualifier = None
self.data.features.append(self._cur_feature)
def location(self, content):
self._cur_feature.location = self._clean_location(content)
def feature_qualifier(self, key, value):
self.feature_qualifier_name([key])
if value is not None:
self.feature_qualifier_description(value)
def feature_qualifier_name(self, content_list):
"""Deal with qualifier names
We receive a list of keys, since you can have valueless keys such as
/pseudo which would be passed in with the next key (since no other
tags separate them in the file)
"""
import Record
for content in content_list:
# the record parser keeps the /s -- add them if we don't have 'em
if not content.startswith("/"):
content = "/%s" % content
# add on a qualifier if we've got one
if self._cur_qualifier is not None:
self._cur_feature.qualifiers.append(self._cur_qualifier)
self._cur_qualifier = Record.Qualifier()
self._cur_qualifier.key = content
def feature_qualifier_description(self, content):
# if we have info then the qualifier key should have a ='s
if '=' not in self._cur_qualifier.key:
self._cur_qualifier.key = "%s=" % self._cur_qualifier.key
cur_content = self._remove_newlines(content)
# remove all spaces from the value if it is a type where spaces
# are not important
for remove_space_key in self.__class__.remove_space_keys:
if remove_space_key in self._cur_qualifier.key:
cur_content = self._remove_spaces(cur_content)
self._cur_qualifier.value = self._normalize_spaces(cur_content)
def base_count(self, content):
self.data.base_counts = content
def origin_name(self, content):
self.data.origin = content
def contig_location(self, content):
"""Signal that we have contig information to add to the record.
"""
self.data.contig = self._clean_location(content)
def sequence(self, content):
"""Add sequence information to a list of sequence strings.
This removes spaces in the data and uppercases the sequence, and
then adds it to a list of sequences. Later on we'll join this
list together to make the final sequence. This is faster than
adding on the new string every time.
"""
assert ' ' not in content
self._seq_data.append(content.upper())
def record_end(self, content):
"""Signal the end of the record and do any necessary clean-up.
"""
# add together all of the sequence parts to create the
# final sequence string
self.data.sequence = "".join(self._seq_data)
# add on the last feature
self._add_feature()
def parse(handle):
"""Iterate over GenBank formatted entries as Record objects.
>>> from Bio import GenBank
>>> handle = open("GenBank/NC_000932.gb")
>>> for record in GenBank.parse(handle):
... print record.accession
['NC_000932']
>>> handle.close()
To get SeqRecord objects use Bio.SeqIO.parse(..., format="gb")
instead.
"""
return iter(Iterator(handle, RecordParser()))
def read(handle):
"""Read a handle containing a single GenBank entry as a Record object.
>>> from Bio import GenBank
>>> handle = open("GenBank/NC_000932.gb")
>>> record = GenBank.read(handle)
>>> print record.accession
['NC_000932']
>>> handle.close()
To get a SeqRecord object use Bio.SeqIO.read(..., format="gb")
instead.
"""
iterator = parse(handle)
try:
first = iterator.next()
except StopIteration:
first = None
if first is None:
raise ValueError("No records found in handle")
try:
second = iterator.next()
except StopIteration:
second = None
if second is not None:
raise ValueError("More than one record found in handle")
return first
def _test():
"""Run the Bio.GenBank module's doctests."""
import doctest
import os
if os.path.isdir(os.path.join("..","..","Tests")):
print "Running doctests..."
cur_dir = os.path.abspath(os.curdir)
os.chdir(os.path.join("..","..","Tests"))
doctest.testmod()
os.chdir(cur_dir)
del cur_dir
print "Done"
elif os.path.isdir(os.path.join("Tests")):
print "Running doctests..."
cur_dir = os.path.abspath(os.curdir)
os.chdir(os.path.join("Tests"))
doctest.testmod()
os.chdir(cur_dir)
del cur_dir
print "Done"
if __name__ == "__main__":
_test()
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