**160**wrote:

I found that Biostars is very helpful!. The following new question puzzles me these days. I can see the genome features and its sequences from NCBI benbank (link) for access Id: DS264095, but Entriz could not retrieve the sequence. The output of the following code shows all Ns in sequence, but with the length that matches the size of the genome (1030563bp). I retrieve the corresponding gbk file, the gbk file just contains the features and CONTIGs, without actual genome sequence. Would you have any suggestions? Thank you!

```
from Bio import SeqIO
from Bio import Entrez
#https://www.ncbi.nlm.nih.gov/nuccore/147747968?report=genbank
handle = Entrez.efetch(db='nuccore', rettype='gb', id='DS264095',retmode='text')
for seqRecord in SeqIO.parse(handle, 'genbank'):
seq=seqRecord.seq
print('seq:',seq[0:100])
print('len:',len(seq))
```

```
#The outputs:
seq:
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
len: 1030563
The retrieved gbk file is as follows, which has different content than the data shown in NCBI site.
LOCUS DS264095 1030563 bp DNA linear CON 18-MAY-2007
DEFINITION Burkholderia mallei FMH scf_1099471655815 genomic scaffold, whole
genome shotgun sequence.
ACCESSION DS264095 AAIQ02000000
VERSION DS264095.1
DBLINK BioProject: PRJNA13987
BioSample: SAMN02435848
KEYWORDS WGS.
SOURCE Burkholderia mallei FMH
ORGANISM Burkholderia mallei FMH
Bacteria; Proteobacteria; Betaproteobacteria; Burkholderiales;
Burkholderiaceae; Burkholderia; pseudomallei group.
REFERENCE 1 (bases 1 to 1030563)
AUTHORS DeShazer,D., Woods,D.E. and Nierman,W.C.
TITLE Direct Submission
JOURNAL Submitted (06-MAR-2007) The Institute for Genomic Research, 9712
Medical Center Drive, Rockville, MD 20850, USA
FEATURES Location/Qualifiers
source 1..1030563
/organism="Burkholderia mallei FMH"
/mol_type="genomic DNA"
/strain="FMH"
/db_xref="taxon:334802"
CONTIG join(AAIQ02000135.1:1..8136,gap(457),AAIQ02000043.1:1..44311,
gap(1031),AAIQ02000166.1:1..3120,gap(1729),AAIQ02000194.1:1..761,
gap(36),AAIQ02000039.1:1..45955,gap(118),AAIQ02000068.1:1..28166,
gap(192),AAIQ02000195.1:1..749,gap(685),AAIQ02000204.1:1..289,
gap(154),AAIQ02000163.1:1..3538,gap(375),AAIQ02000123.1:1..10313,
gap(588),AAIQ02000142.1:1..7218,gap(466),AAIQ02000021.1:1..68386,
gap(239),AAIQ02000069.1:1..27890,gap(395),AAIQ02000099.1:1..17802,
gap(481),AAIQ02000038.1:1..45969,gap(717),AAIQ02000152.1:1..6039,
gap(100),AAIQ02000162.1:1..3813,gap(349),AAIQ02000130.1:1..9302,
gap(951),AAIQ02000104.1:1..15966,gap(744),AAIQ02000082.1:1..23397,
gap(2853),AAIQ02000178.1:1..2005,gap(36),AAIQ02000189.1:1..1160,
gap(36),AAIQ02000120.1:1..10635,gap(36),AAIQ02000184.1:1..1724,
gap(489),AAIQ02000121.1:1..10540,gap(720),AAIQ02000055.1:1..34907,
gap(378),AAIQ02000117.1:1..11883,gap(254),AAIQ02000033.1:1..54313,
gap(288),AAIQ02000137.1:1..7858,gap(863),AAIQ02000115.1:1..12452,
gap(592),AAIQ02000009.1:1..106604,gap(722),AAIQ02000149.1:1..6242,
gap(593),AAIQ02000186.1:1..1381,gap(36),AAIQ02000169.1:1..2881,
gap(468),AAIQ02000148.1:1..6247,gap(437),AAIQ02000164.1:1..3492,
gap(464),AAIQ02000126.1:1..10017,gap(636),AAIQ02000141.1:1..7280,
gap(731),AAIQ02000174.1:1..2399,gap(36),AAIQ02000173.1:1..2519,
gap(246),AAIQ02000013.1:1..98333,gap(237),AAIQ02000168.1:1..2885,
gap(278),AAIQ02000106.1:1..15267,gap(583),AAIQ02000177.1:1..2034,
gap(495),AAIQ02000183.1:1..1748,gap(804),AAIQ02000046.1:1..41423,
gap(357),AAIQ02000167.1:1..3108,gap(36),AAIQ02000171.1:1..2650,
gap(36),AAIQ02000087.1:1..22096,gap(728),AAIQ02000199.1:1..476,
gap(199),AAIQ02000180.1:1..1969,gap(36),AAIQ02000205.1:1..262,
gap(262),AAIQ02000129.1:1..9762,gap(590),AAIQ02000160.1:1..4201,
gap(473),AAIQ02000150.1:1..6226,gap(1027),AAIQ02000176.1:1..2096,
gap(279),AAIQ02000032.1:1..57068,gap(491),AAIQ02000094.1:1..18896,
gap(669),AAIQ02000058.1:1..33027,gap(36),AAIQ02000201.1:1..386,
gap(625),AAIQ02000125.1:1..10029)
//
```

Please format your post appropriately in the future.

27kSure, I will make sure the future posts are well formatted. Thanks Ram.

160