scholarly journals Hypervirulent Klebsiella pneumoniae of Lineage ST66-K2 Caused Tonsillopharyngitis in a German Patient

2021 ◽  
Vol 9 (1) ◽  
pp. 133
Author(s):  
Kathleen Klaper ◽  
Sebastian Wendt ◽  
Christoph Lübbert ◽  
Norman Lippmann ◽  
Yvonne Pfeifer ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Genomic Analysis ◽  
Comparative Genomic ◽  
Snp Analysis ◽  
Whole Genome ◽  
Single Nucleotide ◽  
German Patient ◽  
Genome Data ◽  
Genome Analyses ◽  
Clinical Awareness

Hypervirulent Klebsiella pneumoniae (hvKp) is a novel pathotype that has been rarely described in Europe. This study characterizes a hvKp isolate that caused a community-acquired infection. The hypermucoviscous Klebsiella pneumoniae (K. pneumoniae) strain 18-0005 was obtained from a German patient with tonsillopharyngitis in 2017. Antibiotic susceptibility testing was performed and the genome was sequenced by Illumina and Nanopore technology. Whole genome data were analyzed by conducting core genome multilocus sequence typing (cgMLST) and single nucleotide polymorphism (SNP) analysis. Virulence genes were predicted by applying Kleborate. Phenotypic and whole genome analyses revealed a high similarity of the study isolate 18-0005 to the recently reported antibiotic-susceptible hvKp isolate SB5881 from France and the “ancestral” strain Kp52.145; both were assigned to the ST66-K2 lineage. Comparative genomic analysis of the three plasmids showed that the 18-0005 plasmid II differs from SB5881 plasmid II by an additional 3 kb integrated fragment of plasmid I. Our findings demonstrate the genetic flexibility of hvKp and the occurrence of a strain of the clonal group CG66-K2 in Germany. Hence, it emphasizes the need to improve clinical awareness and infection monitoring of hvKp.

scholarly journals It Is Not All about Single Nucleotide Polymorphisms: Comparison of Mobile Genetic Elements and Deletions in Listeria monocytogenes Genomes Links Cases of Hospital-Acquired Listeriosis to the Environmental Source

2015 ◽  
Vol 53 (11) ◽  
pp. 3492-3500 ◽  
Author(s):  
Qinning Wang ◽  
Nadine Holmes ◽  
Elena Martinez ◽  
Peter Howard ◽  
Grant Hill-Cawthorne ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Genomic Analysis ◽  
Comparative Genomic ◽  
Snp Analysis ◽  
Nucleotide Polymorphisms ◽  
Environmental Isolates ◽  
Single Nucleotide ◽  
Content Type ◽  
Serotype 1 ◽  
Hospital Acquired

The control of food-borne outbreaks caused byListeria monocytogenesin humans relies on the timely identification of food or environmental sources and the differentiation of outbreak-related isolates from unrelated ones. This study illustrates the utility of whole-genome sequencing for examining the link between clinical and environmental isolates ofL. monocytogenesassociated with an outbreak of hospital-acquired listeriosis in Sydney, Australia. Comparative genomic analysis confirmed an epidemiological link between the three clinical and two environmental isolates. Single nucleotide polymorphism (SNP) analysis showed that only two SNPs separated the three human outbreak isolates, which differed by 19 to 20 SNPs from the environmental isolates and 71 to >10,000 SNPs from sporadicL. monocytogenesisolates. The chromosomes of all human outbreak isolates and the two suspected environmental isolates were syntenic. In contrast to the genomes of background sporadic isolates, all epidemiologically linked isolates contained two novel prophages and a previously unreported clustered regularly interspaced short palindromic repeat (CRISPR)-associated (Cas) locus subtype sequence. The mobile genetic element (MGE) profile of these isolates was distinct from that of the other serotype 1/2b reference strains and sporadic isolates. The identification of SNPs and clonally distinctive MGEs strengthened evidence to distinguish outbreak-related isolates ofL. monocytogenesfrom cocirculating endemic strains.

scholarly journals Whole-Genome Single-Nucleotide-Polymorphism Analysis for Discrimination of Clostridium botulinum Group I Strains

2014 ◽  
Vol 80 (7) ◽  
pp. 2125-2132 ◽  
Author(s):  
Narjol Gonzalez-Escalona ◽  
Ruth Timme ◽  
Brian H. Raphael ◽  
Donald Zink ◽  
Shashi K. Sharma
Keyword(s):  
Single Nucleotide Polymorphism ◽  
Clostridium Botulinum ◽  
Toxin Gene ◽  
Polymorphism Analysis ◽  
Snp Analysis ◽  
Whole Genome ◽  
Nucleotide Polymorphism ◽  
Single Nucleotide ◽  
Content Type ◽  
Group I

ABSTRACTClostridium botulinumis a genetically diverse Gram-positive bacterium producing extremely potent neurotoxins (botulinum neurotoxins A through G [BoNT/A-G]). The complete genome sequences of three strains harboring only the BoNT/A1 nucleotide sequence are publicly available. Although these strains contain a toxin cluster (HA+OrfX−) associated with hemagglutinin genes, little is known about the genomes of subtype A1 strains (termed HA−OrfX+) that lack hemagglutinin genes in the toxin gene cluster. We sequenced the genomes of three BoNT/A1-producingC. botulinumstrains: two strains with the HA+OrfX−cluster (69A and 32A) and one strain with the HA−OrfX+cluster (CDC297). Whole-genome phylogenic single-nucleotide-polymorphism (SNP) analysis of these strains along with other publicly availableC. botulinumgroup I strains revealed five distinct lineages. Strains 69A and 32A clustered with theC. botulinumtype A1 Hall group, and strain CDC297 clustered with theC. botulinumtype Ba4 strain 657. This study reports the use of whole-genome SNP sequence analysis for discrimination ofC. botulinumgroup I strains and demonstrates the utility of this analysis in quickly differentiatingC. botulinumstrains harboring identical toxin gene subtypes. This analysis further supports previous work showing that strains CDC297 and 657 likely evolved from a common ancestor and independently acquired separate BoNT/A1 toxin gene clusters at distinct genomic locations.

scholarly journals High-Level Aminoglycoside Resistance in Human Clinical Klebsiella pneumoniae Complex Isolates and Characteristics of armA-Carrying IncHI5 Plasmids

2021 ◽  
Vol 12 ◽  
Author(s):  
Xueya Zhang ◽  
Qiaoling Li ◽  
Hailong Lin ◽  
Wangxiao Zhou ◽  
Changrui Qian ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Resistance Genes ◽  
Genomic Analysis ◽  
Comparative Genomic Analysis ◽  
Conjugative Plasmid ◽  
Comparative Genomic ◽  
Aminoglycoside Resistance ◽  
Life Threatening ◽  
Aminoglycoside Resistance Genes ◽  
High Level

Aminoglycosides are important options for treating life-threatening infections. However, high levels of aminoglycoside resistance (HLAR) among Klebsiella pneumoniae isolates have been observed to be increasing frequently. In this study, a total of 292 isolates of the K. pneumoniae complex from a teaching hospital in China were analyzed. Among these isolates, the percentage of HLAR strains was 13.7% (40/292), and 15 aminoglycoside resistance genes were identified among the HLAR strains, with rmtB being the most dominant resistance gene (70%, 28/40). We also described an armA-carrying Klebsiella variicola strain KP2757 that exhibited a high-level resistance to all aminoglycosides tested. Whole-genome sequencing of KP2757 demonstrated that the strain contained one chromosome and three plasmids, with all the aminoglycoside resistance genes (including two copies of armA and six AME genes) being located on a conjugative plasmid, p2757-346, belonging to type IncHI5. Comparative genomic analysis of eight IncHI5 plasmids showed that six of them carried two copies of the intact armA gene in the complete or truncated Tn1548 transposon. To the best of our knowledge, for the first time, we observed that two copies of armA together with six AME genes coexisted on the same plasmid in a strain of K. variicola with HLAR. Comparative genomic analysis of eight armA-carrying IncHI5 plasmids isolated from humans and sediment was performed, suggesting the potential for dissemination of these plasmids among bacteria from different sources. These results demonstrated the necessity of monitoring the prevalence of IncHI5 plasmids to restrict their worldwide dissemination.

scholarly journals Mechanism of PQQ and CoQ10 overproduction in Methylobacterium as revealed by comparative genomic analysis between mutant and wild-type strains

2020 ◽  
Author(s):  
Changle Zhao ◽  
Yinping Wan ◽  
Xiaojie Cao ◽  
Huili Zhang ◽  
Xin Bao
Keyword(s):  
Mutant Strain ◽  
Type Strain ◽  
Wild Type Strain ◽  
Genomic Analysis ◽  
Comparative Genomic Analysis ◽  
Comparative Genomic ◽  
Regulation Mechanism ◽  
Whole Genome ◽  
Wild Type ◽  
Coq10 Production

Abstract Background The microbial synthesis of pyrroloquinoline quinone (PQQ) and Coenzyme Q10 (CoQ10) remains the most promising industrial production route. Methylobacterium has been used to generate PQQ and other value-added chemicals from cheap carbon feedstocks.However, the low PQQ and CoQ10 production capacity of the Methylobacterium strains is a major limitation The regulation mechanism for PQQ and CoQ10 biosynthesis in this strain has also not been fully elucidated. Results Methylobacterium sp. CLZ strain was isolated from soil contaminated with chemical wastewater, which can simultaneously produce PQQ, CoQ10, and carotenoids by using cheap methanol as carbon source. We investigated a mutant strain NI91, which increased the PQQ and CoQ10 yield by 72.44% and 59.80%, respectively. Whole-genome sequencing of NI91 and wild-type strain CLZ revealed that both contain a 5.28 Mb chromosome. The comparative genomic analysis and validation study revealed that a significant increase in biomass and PQQ production was associated with the base mutations in the methanol dehydrogenase (MDH) synthesis genes, mxaD and mxaJ. The significant increase in CoQ10 production may be associated with the base mutations in dxs gene, a key gene in the MEP/DOXP pathway. Conclusions A PQQ producing strain that simultaneously produces CoQ10 and carotenoids was selected and after ANI analysis, named as Methylobacterium sp. CLZ. After random mutagenesis of this strain, we obtained NI91 strain, which showed increased production of PQQ and CoQ10. Based on comparative genomic analysis of the whole genome of mutant strain NI91 and wild-type strain CLZ, a total of 270 SNPs and InDels events were detected, which provided a reference for subsequent research. The mutations in mxaD, mxaJ and dxs genes may be related to the high yield of PQQ and CoQ10. These findings will enhance our understanding of the PQQ and CoQ10 over-production mechanism in Methylobacterium sp. NI91 at the genomic level. It will also provide useful clues for strain engineering in order to improve the PQQ and CoQ10 production.

Genome typing and epidemiology of human listeriosis in New Zealand 1999-2018

2021 ◽  
Author(s):  
Lucia Rivas ◽  
Shevaun Paine ◽  
Pierre-Yves Dupont ◽  
Audrey Tiong ◽  
Beverley Horn ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
New Zealand ◽  
Epidemiological Data ◽  
Common Source ◽  
Snp Analysis ◽  
Whole Genome ◽  
Single Nucleotide ◽  
Low Genetic Diversity ◽  
Geographical Regions ◽  
Sequence Types

This study describes the epidemiology of listeriosis in New Zealand (NZ) between 1999 and 2018, as well as the retrospective whole genome sequencing (WGS) of 453 Listeria monocytogenes isolates corresponding to 95% of the human cases within this period. The average notified rate of listeriosis was 0.5 cases per 100,000 population and non-pregnancy associated cases were more prevalent than pregnancy-associated cases (average 19 and 5 cases per annum, respectively). Analysis of WGS data was assessed using multi-locus sequencing typing (MLST), including core-genome and whole-genome MLST (cgMLST and wgMLST) and single-nucleotide polymorphism (SNP) analysis. Thirty-nine sequence types (STs) were identified, with the most common being, ST1 (21.9%), ST4 (13.2%), ST2 (11.3%), ST120 (6.1%) and ST155 (6.4%). A total of 291 different cgMLST types were identified, with the majority (n = 243) of types observed as a single isolate, consistent with the observation that listeriosis is predominately sporadic. Amongst the 49 cgMLST types containing two or more isolates, 18 cgMLST types contained 2-4 isolates (50 isolates in total, including three outbreak-associated isolates) that shared low genetic diversity (0-2 whole-genome alleles), some of which were dispersed in time or geographical regions. SNP-analysis also produced comparable results to wgMLST. The low genetic diversity within these clusters suggests a potential common source but incomplete epidemiological data impaired retrospective epidemiological investigations. Prospective use of WGS analysis, together with thorough exposure information from cases will potentially identify future outbreaks more rapidly and possibly those that have been undetected for some time over different geographically regions.

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