Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.7.1.1 (
nitrate reductase
)
3,728
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Corynebacterium diphtheriae
is the etiological agent of diphtheria, a disease caused by the presence of the diphtheria toxin. However, an increasing number of records report non-toxigenic
C. diphtheriae
infections. Here, a
C. diphtheriae
strain was recovered from a patient with a past history of bronchiectasis who developed a severe tracheo-
bronchitis
with multiple whitish lesions of the distal trachea and the mainstem bronchi. Whole-genome sequencing (WGS), performed in parallel with PCR targeting the toxin gene and the Elek test, provided clinically relevant results in a short turnaround time, showing that the isolate was non-toxigenic. A comparative genomic analysis of the new strain (CHUV2995) with 56 other publicly available genomes of
C. diphtheriae
revealed that the strains CHUV2995, CCUG 5865 and CMCNS703 share a lower average nucleotide identity (ANI) (95.24 to 95.39%) with the
C. diphtheriae
NCTC 11397
T
reference genome than all other
C. diphtheriae
genomes (>98.15%). Core genome phylogeny confirmed the presence of two monophyletic clades. Based on these findings, we propose here two new
C. diphtheriae
subspecies to replace the lineage denomination used in previous multilocus sequence typing studies:
C. diphtheriae
subsp.
lausannense
subsp. nov. (instead of lineage-2), regrouping strains CHUV2995, CCUG 5865, and CMCNS703, and
C. diphtheriae
subsp.
diphtheriae
subsp. nov, regrouping all other
C. diphtheriae
in the dataset (instead of lineage-1). Interestingly, members of subspecies
lausannense
displayed a larger genome size than subspecies
diphtheriae
and were enriched in COG categories related to transport and metabolism of lipids (I) and inorganic ion (P). Conversely, they lacked all genes involved in the synthesis of pili (SpaA-type, SpaD-type and SpaH-type), molybdenum cofactor and of the
nitrate reductase
. Finally, the CHUV2995 genome is particularly enriched in mobility genes and harbors several prophages. The genome encodes a type II-C CRISPR-Cas locus with 2 spacers that lacks
csn2
or
cas4
, which could hamper the acquisition of new spacers and render strain CHUV2995 more susceptible to bacteriophage infections and gene acquisition through various mechanisms of horizontal gene transfer.
...
PMID:Distinct Genomic Features Characterize Two Clades of
Corynebacterium diphtheriae
: Proposal of
Corynebacterium diphtheriae
Subsp.
diphtheriae
Subsp. nov. and
Corynebacterium diphtheriae
Subsp.
lausannense
Subsp. nov. 3017 53
