scholarly journals Multilocus Sequence-Typing of Anthrax Microbe Strains Isolated in Russia and Neighboring Countries

Author(s):  
Yu. O. Goncharova ◽  
I. V. Bakhteeva ◽  
R. I. Mironova ◽  
A. G. Bogun ◽  
K. V. Khlopova ◽  
...  

Objective – genotyping by multilocus sequence-typing (MLST) and phylogenetic analysis of 40 Bacillus anthracis strains isolated in Russia and neighboring countries.Materials and methods. In this study, the sequences of seven housekeeping genes of B. anthracis strains were assembled based on the data of a whole genome new generation sequencing, after which the identified mutations and their coordinates were described. The obtained sequences were used for genotyping of the investigated sample using the MLST method. The results are compared with the data presented in PubMLST database. A phylogenetic analysis was performed for the in silico fused sequences of the seven loci of the identified sequence types. The MEGA 7.0 software package was used to build the dendrograms.Results and discussion. Two sequence types (ST) have been found in the examined sample: 35 strains belong to ST-1, and five strains that differed by one common mutation at the glpF locus – to ST-3 (according to PubMLST coding), which emphasizes the genetic separation of this group of strains. One strain has a unique mutation in the gmk gene located outside the region used for MLST. 

2007 ◽  
Vol 56 (11) ◽  
pp. 1460-1466 ◽  
Author(s):  
Seon Young Choi ◽  
Yoon-Seong Jeon ◽  
Je Hee Lee ◽  
Boram Choi ◽  
Sun Hwa Moon ◽  
...  

The multilocus sequence typing scheme used previously for phylogenetic analysis of Escherichia coli was applied to 107 clinical isolates of Shigella flexneri. DNA sequencing of 3423 bp throughout seven housekeeping genes identified eight new allele types and ten new sequence types among the isolates. S. flexneri serotypes 1–5, X and Y were clustered together in a group containing many allelic variants while serotype 6 formed a distinct group, as previously established.


Author(s):  
А.Т. ДАУГАЛИЕВА ◽  
С.Т. ДАУГАЛИЕВА ◽  
Б.С. АРЫНГАЗИЕВ ◽  
Т.А. ЛАВРЕНТЬЕВА

Целью исследования было определение таксономической структуры микробиома кишечника крупного рогатого скота породы Абердин-Ангус с помощью технологии секвенирования нового поколения. 16S метагеномный анализ, позволил определить микробный состав содержимого кишечника, минуя стадию культивирования на питательных средах. Проведена генетическая идентификация и получен таксономический профиль всех присутствующих бактерий, в том числе и некультивируемых форм. The aim of the study was to determine the taxonomic structure of the intestinal microbiome of Aberdeen Angus cattle using a new generation sequencing technology. 16S metagenomic analysis made it possible to determine the microbial composition of the intestinal contents bypassing the stage of cultivation on nutrient media. Genetic identification was carried out and a taxonomic profile of all bacteria present, including non-cultivated forms, was obtained. Key words: microbiome, cattle, Aberdeen Angus, next generation sequencing.


2018 ◽  
Vol 85 (4) ◽  
Author(s):  
Sara Kovanen ◽  
Mirko Rossi ◽  
Mari Pohja-Mykrä ◽  
Timo Nieminen ◽  
Mirja Raunio-Saarnisto ◽  
...  

ABSTRACTPoultry are considered a major reservoir and source of human campylobacteriosis, but the roles of environmental reservoirs, including wild birds, have not been assessed in depth. In this study, we isolated and characterizedCampylobacter jejunifrom western jackdaws (n= 91, 43%), mallard ducks (n= 82, 76%), and pheasants (n= 9, 9%). Most of the western jackdaw and mallard duckC. jejuniisolates represented multilocus sequence typing (MLST) sequence types (STs) that diverged from those previously isolated from human patients and various animal species, whereas all pheasant isolates represented ST-19, a common ST among human patients and other hosts worldwide. Whole-genome MLST revealed that mallard duck ST-2314 and pheasant ST-19 isolates represented bacterial clones that were genetically highly similar to human isolates detected previously. Further analyses revealed that in addition to a divergent ClonalFrame genealogy, certain genomic characteristics of the western jackdawC. jejuniisolates, e.g., a novelcdtABCgene cluster and the type VI secretion system (T6SS), may affect their host specificity and virulence. Game birds may thus pose a risk for acquiring campylobacteriosis; therefore, hygienic measures during slaughter and meat handling warrant special attention.IMPORTANCEThe roles of environmental reservoirs, including wild birds, in the molecular epidemiology ofCampylobacter jejunihave not been assessed in depth. Our results showed that game birds may pose a risk for acquiring campylobacteriosis, because they hadC. jejunigenomotypes highly similar to human isolates detected previously. Therefore, hygienic measures during slaughter and meat handling warrant special attention. On the contrary, a unique phylogeny was revealed for the western jackdaw isolates, and certain genomic characteristics identified among these isolates are hypothesized to affect their host specificity and virulence. Comparative genomics within sequence types (STs), using whole-genome multilocus sequence typing (wgMLST), and phylogenomics are efficient methods to analyze the genomic relationships ofC. jejuniisolates.


2017 ◽  
Vol 62 (1) ◽  
Author(s):  
Tse H. Koh ◽  
Nurdyana Binte Abdul Rahman ◽  
Jeanette W. P. Teo ◽  
My-Van La ◽  
Balamurugan Periaswamy ◽  
...  

ABSTRACT Whole-genome sequencing was performed on 16 isolates of the carbapenemase-producing Enterobacter cloacae complex to determine the flanking regions of bla IMI-type genes. Phylogenetic analysis of multilocus sequence typing (MLST) targets separated the isolates into 4 clusters. The bla IMI-type genes were all found on Xer-dependent integrative mobile elements (IMEX). The IMEX elements of 5 isolates were similar to those described in Canada, while the remainder were novel. Five isolates had IMEX elements lacking a resolvase and recombinase.


2011 ◽  
Vol 57 (12) ◽  
pp. 982-986 ◽  
Author(s):  
Michelle L. Shuel ◽  
Kathleen E. Karlowsky ◽  
Dennis K.S. Law ◽  
Raymond S.W. Tsang

Population biology of Haemophilus influenzae can be studied by multilocus sequence typing (MLST), and isolates are assigned sequence types (STs) based on nucleotide sequence variations in seven housekeeping genes, including fucK. However, the ST cannot be assigned if one of the housekeeping genes is absent or cannot be detected by the current protocol. Occasionally, strains of H. influenzae have been reported to lack the fucK gene. In this study, we examined the prevalence of this mutation among our collection of H. influenzae isolates. Of the 704 isolates studied, including 282 encapsulated and 422 nonencapsulated isolates, nine were not typeable by MLST owing to failure to detect the fucK gene. All nine fucK-negative isolates were nonencapsulated and belonged to various biotypes. DNA sequencing of the fucose operon region confirmed complete deletion of genes in the operon in seven of the nine isolates, while in the remaining two isolates, some of the genes were found intact or in parts. The significance of these findings is discussed.


Author(s):  
Roberto Tuberosa ◽  
◽  
Elisabetta Frascaroli ◽  
Marco Maccaferri ◽  
Silvio Salvi ◽  
...  

This chapter illustrates how genomics and other -omics approaches coupled with new-generation sequencing (NGS) platforms have been deployed to dissect the genetic make-up of RSA traits and better understand their functions, particularly under environmentally constrained conditions that commonly occur in most farmed soils. The major emphasis is devoted to studies during the past two decades in crops and only occasional reference is provided to the vast literature from RSA studies conducted in Arabidopsis and other model plants. The chapter also provides examples on how, in some cases, this knowledge is already benefiting farmers and how it can help in reducing the environmental impact of agriculture worldwide.


2019 ◽  
Vol 14 (15) ◽  
pp. 1281-1292 ◽  
Author(s):  
Giovanni Lorenzin ◽  
Erika Scaltriti ◽  
Franco Gargiulo ◽  
Francesca Caccuri ◽  
Giorgio Piccinelli ◽  
...  

Aim: This study aims to characterize clinical strains of Acinetobacter baumannii with an extensively drug-resistant phenotype. Methods: VITEK® 2, Etest® method and broth microdilution method for colistin were used. PCR analysis and multilocus sequence typing Pasteur scheme were performed to identify bla-OXA genes and genetic relatedness, respectively. Whole-genome sequencing analysis was used to characterize three isolates. Results: All the isolates were susceptible only to polymyxins. blaOXA-23-like gene was the only acquired carbapenemase gene in 88.2% of the isolates. Multilocus sequence typing identified various sequence types: ST2, ST19, ST195, ST577 and ST632. Two new sequence types, namely, ST1279 and ST1280, were detected by whole-genome sequencing. Conclusion: This study showed that carbapenem-resistant A. baumannii isolates causing infections in intensive care units almost exclusively produce OXA-23, underlining their frequent spread in Italy.


Microbiology ◽  
2010 ◽  
Vol 156 (7) ◽  
pp. 2035-2045 ◽  
Author(s):  
Claudia Picozzi ◽  
Gaia Bonacina ◽  
Ileana Vigentini ◽  
Roberto Foschino

Lactobacillus sanfranciscensis is a lactic acid bacterium that characterizes the sourdough environment. The genetic differences of 24 strains isolated in different years from sourdoughs, mostly collected in Italy, were examined and compared by PFGE and multilocus sequence typing (MLST). The MLST scheme, based on the analysis of six housekeeping genes (gdh, gyrA, mapA, nox, pgmA and pta) was developed for this study. PFGE with the restriction enzyme ApaI proved to have higher discriminatory power, since it revealed 22 different pulsotypes, while 19 sequence types were recognized through MLST analysis. Notably, restriction profiles generated from three isolates collected from the same firm but in three consecutive years clustered in a single pulsotype and showed the same sequence type, emphasizing the fact that the main factors affecting the dominance of a strain are correlated with processing conditions and the manufacturing environment rather than the geographical area. All results indicated a limited recombination among genes and the presence of a clonal population in L. sanfranciscensis. The MLST scheme proposed in this work can be considered a useful tool for characterization of isolates and for in-depth examination of the strain diversity and evolution of this species.


2009 ◽  
Vol 75 (18) ◽  
pp. 5853-5862 ◽  
Author(s):  
K. Liu ◽  
S. J. Knabel ◽  
E. G. Dudley

ABSTRACT DNA sequence-based molecular subtyping methods such as multilocus sequence typing (MLST) are commonly used to generate phylogenetic inferences for monomorphic pathogens. The development of an effective MLST scheme for subtyping Escherichia coli O157:H7 has been hindered in the past due to the lack of sequence variation found within analyzed housekeeping and virulence genes. A recent study suggested that rhs genes are under strong positive selection pressure, and therefore in this study we analyzed these genes within a diverse collection of E. coli O157:H7 strains for sequence variability. Eighteen O157:H7 strains from lineages I and II and 15 O157:H7 strains from eight clades were included. Examination of these rhs genes revealed 44 polymorphic loci (PL) and 10 sequence types (STs) among the 18 lineage strains and 280 PL and 12 STs among the 15 clade strains. Phylogenetic analysis using rhs genes generally grouped strains according to their known lineage and clade classifications. These findings also suggested that O157:H7 strains from clades 6 and 8 fall into lineage I/II and that strains of clades 1, 2, 3, and 4 fall into lineage I. Additionally, unique markers were found in rhsA and rhsJ that might be used to define clade 8 and clade 6. Therefore, rhs genes may be useful markers for phylogenetic analysis of E. coli O157:H7.


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