scholarly journals Clinical and Microbiological Characteristics of Mycobacterium kansasii Pulmonary Infections in China

Author(s):  
Yinjuan Guo ◽  
Yanhua Cao ◽  
Haican Liu ◽  
Jinghui Yang ◽  
Weiping Wang ◽  
...  

M. kansasii type I is the main genotype spreading worldwide. The molecular history of the global spread of type I isolates remains largely unclear. We conducted a detailed analysis of genomic evolution of global M. kansasii isolates. Our results suggest that M. kansasii isolates exhibit greater genetic diversity globally.

mBio ◽  
2018 ◽  
Vol 9 (4) ◽  
Author(s):  
Edward W. Davis ◽  
Javier F. Tabima ◽  
Alexandra J. Weisberg ◽  
Lucas Dantas Lopes ◽  
Michele S. Wiseman ◽  
...  

ABSTRACTRathayibacter toxicusis a species of Gram-positive, corynetoxin-producing bacteria that causes annual ryegrass toxicity, a disease often fatal to grazing animals. A phylogenomic approach was employed to model the evolution ofR. toxicusto explain the low genetic diversity observed among isolates collected during a 30-year period of sampling in three regions of Australia, gain insight into the taxonomy ofRathayibacter, and provide a framework for studying these bacteria. Analyses of a data set of more than 100 sequencedRathayibactergenomes indicated thatRathayibacterforms nine species-level groups.R. toxicusis the most genetically distant, and evidence suggested that this species experienced a dramatic event in its evolution. Its genome is significantly reduced in size but is colinear to those of sister species. Moreover,R. toxicushas low intergroup genomic diversity and almost no intragroup genomic diversity between ecologically separated isolates.R. toxicusis the only species of the genus that encodes a clustered regularly interspaced short palindromic repeat (CRISPR) locus and that is known to host a bacteriophage parasite. The spacers, which represent a chronological history of infections, were characterized for information on past events. We propose a three-stage process that emphasizes the importance of the bacteriophage and CRISPR in the genome reduction and low genetic diversity of theR. toxicusspecies.IMPORTANCERathayibacter toxicusis a toxin-producing species found in Australia and is often fatal to grazing animals. The threat of introduction of the species into the United States led to its inclusion in the Federal Select Agent Program, which makesR. toxicusa highly regulated species. This work provides novel insights into the evolution ofR. toxicus.R. toxicusis the only species in the genus to have acquired a CRISPR adaptive immune system to protect against bacteriophages. Results suggest that coexistence with the bacteriophage NCPPB3778 led to the massive shrinkage of theR. toxicusgenome, species divergence, and the maintenance of low genetic diversity in extant bacterial groups. This work contributes to an understanding of the evolution and ecology of an agriculturally important species of bacteria.


2014 ◽  
Vol 81 (4) ◽  
pp. 1520-1529 ◽  
Author(s):  
Sujan Timilsina ◽  
Mustafa O. Jibrin ◽  
Neha Potnis ◽  
Gerald V. Minsavage ◽  
Misrak Kebede ◽  
...  

ABSTRACTFourXanthomonasspecies are known to cause bacterial spot of tomato and pepper, but the global distribution and genetic diversity of these species are not well understood. A collection of bacterial spot-causing strains from the Americas, Africa, Southeast Asia, and New Zealand were characterized for genetic diversity and phylogenetic relationships using multilocus sequence analysis of six housekeeping genes. By examining strains from different continents, we found unexpected phylogeographic patterns, including the global distribution of a single multilocus haplotype ofX. gardneri, possible regional differentiation inX. vesicatoria, and high species diversity on tomato in Africa. In addition, we found evidence of multiple recombination events betweenX. euvesicatoriaandX. perforans.Our results indicate that there have been shifts in the species composition of bacterial spot pathogen populations due to the global spread of dominant genotypes and that recombination between species has generated genetic diversity in these populations.


2013 ◽  
Vol 79 (22) ◽  
pp. 6903-6910 ◽  
Author(s):  
Joseph R. Loquasto ◽  
Rodolphe Barrangou ◽  
Edward G. Dudley ◽  
Buffy Stahl ◽  
Chun Chen ◽  
...  

ABSTRACTMany strains ofBifidobacterium animalissubsp.lactisare considered health-promoting probiotic microorganisms and are commonly formulated into fermented dairy foods. Analyses of previously sequenced genomes ofB. animalissubsp.lactishave revealed little genetic diversity, suggesting that it is a monomorphic subspecies. However, during a multilocus sequence typing survey ofBifidobacterium, it was revealed thatB. animalissubsp.lactisATCC 27673 gave a profile distinct from that of the other strains of the subspecies. As part of an ongoing study designed to understand the genetic diversity of this subspecies, the genome of this strain was sequenced and compared to other sequenced genomes ofB. animalissubsp.lactisandB. animalissubsp.animalis. The complete genome of ATCC 27673 was 1,963,012 bp, contained 1,616 genes and 4 rRNA operons, and had a G+C content of 61.55%. Comparative analyses revealed that the genome of ATCC 27673 contained six distinct genomic islands encoding 83 open reading frames not found in other strains of the same subspecies. In four islands, either phage or mobile genetic elements were identified. In island 6, a novel clustered regularly interspaced short palindromic repeat (CRISPR) locus which contained 81 unique spacers was identified. This type I-E CRISPR-cassystem differs from the type I-C systems previously identified in this subspecies, representing the first identification of a different system inB. animalissubsp.lactis. This study revealed that ATCC 27673 is a strain ofB. animalissubsp.lactiswith novel genetic content and suggests that the lack of genetic variability observed is likely due to the repeated sequencing of a limited number of widely distributed commercial strains.


2019 ◽  
Vol 85 (24) ◽  
Author(s):  
Maryam Ansari ◽  
S. Mohsen Taghavi ◽  
Habiballah Hamzehzarghani ◽  
Miryam Valenzuela ◽  
María Ines Siri ◽  
...  

ABSTRACT Tomato bacterial canker caused by Clavibacter michiganensis subsp. michiganensis is one of the most important seed-borne tomato diseases around the globe. The disease was initially reported in 1993 in Iran, and it became a rising threat for the multibillion dollar tomato industry of the country during the last decade. In this study, using phylogeographic analyses, we determined genetic diversity and geographic distribution of C. michiganensis subsp. michiganensis in Iran. Our field surveys showed that the pathogen is expanding into the southern and eastern areas of the country. Furthermore, multilocus sequence analysis and typing (MLSA/MLST) using the sequences of five housekeeping genes (atpD, gyrB, ppk, recA, and rpoB) revealed that 37 C. michiganensis subsp. michiganensis strains isolated in Iran had high genetic diversity and placed in 15 sequence types (STs), while all the available 184 worldwide C. michiganensis subsp. michiganensis sequences were placed in 43 STs. MLSA divided the worldwide C. michiganensis subsp. michiganensis strains into two phylogroups (I and II). Among the 37 strains isolated in Iran, 30 strains clustered in phylogroup I, while 7 strains clustered in phylogroup II. Phylogeographic data inferred from the allelic profile of the five housekeeping genes suggested multiple introductions of C. michiganensis subsp. michiganensis inoculum into Iran, while the geographic origin of the Iranian C. michiganensis subsp. michiganensis strains remains undetermined. Further analyses using higher numbers of strains are warranted to decipher the evolutionary history of C. michiganensis subsp. michiganensis in Iran. Additionally, stricter seed/transplant inspections are recommended to reduce the risk of pathogen expansion to areas with no history of the disease. IMPORTANCE Clavibacter michiganensis subsp. michiganensis, the causal agent of tomato bacterial canker disease, is one of the economically important pathogens of solanaceous crops (e.g., eggplant, pepper, and tomato) around the world. The disease occurs in many countries, with a particular importance in regions characterized by high precipitation and humid environmental conditions. As a seed-borne pathogen, C. michiganensis subsp. michiganensis is included in the A2 (high risk) list of quarantine pathogens by the European and Mediterranean Plant Protection Organization (EPPO). Bacterial canker disease was reported for the first time in 1993 in Iran, while the geographic distribution, genetic diversity, and phylogenetic position of the causal agent remain undetermined. In this study, using the multilocus sequence analysis and typing (MLSA/MLST) approach, we provided a phylogeographic scheme for the C. michiganensis subsp. michiganensis strains isolated in Iran. Furthermore, global-scale phylogenetic analyses led to determination of phylogenetic position of Iranian C. michiganensis subsp. michiganensis strains among worldwide population of the pathogen. Based on diversity parameters and population structure, we suggest relatively higher genetic diversity of the bacterial canker pathogen in Iran than has so far been observed in the other areas of the world. Results obtained in this study provide a novel insight into the genetic diversity and population structure of the bacterial canker pathogen on a global scale.


Author(s):  
M. B. Prentice ◽  
S. R. Vye ◽  
S. R. Jenkins ◽  
P. W. Shaw ◽  
J. E. Ironside

AbstractIntroductions of invasive, non-native species in the marine environment are increasing as human activity within coastal areas rises. Genetic datasets are useful tools to identify source populations, track routes of invasions, and illuminate the role of genetic variation in the establishment and subsequent spread of novel introductions. Here, a microsatellite dataset is used to estimate the genetic diversity and population structure of 7 introduced Didemnum vexillum populations in Britain and Ireland, 4 of which are associated with aquaculture and 3 with marinas. Genetic differentiation observed between these populations indicates human-mediated transport as the main mechanism underlying the population structure of D. vexillum in Britain and Ireland. In addition to elucidating patterns of population structure we found that aquaculture sites showed significantly higher genetic diversity (measured as allelic richness) in comparison to the marina sites. We discuss these findings in relation to the history of each invasion, the complex life history of D. vexillum, and available evidence of the relative invasiveness of these populations. Our results show numerous interesting patterns which highlight further research avenues to elucidate the complex factors underlying the global spread of this successful invader.


2015 ◽  
pp. 151-158
Author(s):  
A. Zaostrovtsev

The review considers the first attempt in the history of Russian economic thought to give a detailed analysis of informal institutions (IF). It recognizes that in general it was successful: the reader gets acquainted with the original classification of institutions (including informal ones) and their genesis. According to the reviewer the best achievement of the author is his interdisciplinary approach to the study of problems and, moreover, his bias on the achievements of social psychology because the model of human behavior in the economic mainstream is rather primitive. The book makes evident that namely this model limits the ability of economists to analyze IF. The reviewer also shares the author’s position that in the analysis of the IF genesis the economists should highlight the uncertainty and reject economic determinism. Further discussion of IF is hardly possible without referring to this book.


Author(s):  
Tupitsyn V.V. ◽  
Bataev Kh.M. ◽  
Men’shikova A.N. ◽  
Godina Z.N.

Relevance. Information about the cardiovascular diseases risk factors (CVD RF) for in men with chronic lung inflam-matory pathology (CLID) is contradictory and requires clarification. Aim. To evaluate the peculiarities of CVD RF in men under 60 years of age with CLID in myocardial infarction (MI) to improve prevention. Material and methods. The study included men aged 19-60 years old with type I myocardial infarction. Patients are divided into two age-comparable groups: I - the study group, with CLID - 142 patients; II - control, without it - 424 patients. A comparative analysis of the frequency of observation of the main and additional cardiovascular risk fac-tors in groups was performed. Results. In patients of the study group, more often than in the control group we observed: hereditary burden of is-chemic heart disease (40.8 and 31.6%, respectively; p = 0.0461) and arterial hypertension (54.2 and 44.6%; p = 0.0461), frequent colds (24.6 and 12.0%; p = 0.0003), a history of extrasystoles (19.7 and 12.7%; p = 0.04); chronic foci of infections of internal organs (75.4 and 29.5%; p˂0.0001), non-ulcer lesions of the digestive system (26.1 and 14.6%; p = 0.007), smoking (95.1 and 66.3%; p˂0.0001), MI in winter (40.8 and 25.9%; p = 0.006). Less commonly were observed: oral cavity infections (9.2 and 23.6%; p˂0.0001); hypodynamia (74.5 and 82.5%; p = 0.0358), over-weight (44.4 and 55.2%; p = 0.0136), a subjective relationship between the worsening of the course of coronary heart disease and the season of the year (43.7 and 55.2%; p = 0.0173) and MI - in the autumn (14.1 and 21.9%; p = 0.006) period. Conclusions. The structure of CVD RF in men under 60 years of age with CLID with MI is characterized by the pre-dominance of smoking, non-ulcer pathology of the digestive system, frequent pro-student diseases, meteorological dependence, a history of cardiac arrhythmias and foci of internal organ infections. It is advisable to use the listed factors when planning preventive measures in such patients.


2015 ◽  
Vol 13 (1) ◽  
pp. 39-57 ◽  
Author(s):  
Caroline Robion-Brunner ◽  
Anne Haour ◽  
Marie-Pierre Coustures ◽  
Louis Champion ◽  
Didier Béziat

In the context of the “Crossroads of Empires” project led by Anne Haour, one strand of enquiry aims to understand the history of blacksmith groups and the development of iron production in Dendi country, in the northern Republic of Benin. Numerous remains of iron production have been discovered, showing a great variability in furnace design and waste assemblages. At least three smelting traditions can be distinguished. In this paper, we present the smelting site of Kompa Moussékoubou (10th/11th c. AD) which has been investigated by archaeological and archaeometric methods. Beyond the archaeometallurgical results, the excavation of a 1 x 2 m trench on a settlement mound nearby and survey work, which place the site within its wider context, are also discussed. In particular, we offer a detailed analysis of the ceramics recovered during test pitting and within one of the furnaces itself. This paper thus offers a rare opportunity to combine archaeometallurgical and ceramics data.


2006 ◽  
Vol 194 (5) ◽  
pp. 552-560 ◽  
Author(s):  
Elizabeth Margaret Maloney ◽  
Yoshihisa Yamano ◽  
Paul C. VanVeldhuisen ◽  
Takashi Sawada ◽  
Norma Kim ◽  
...  

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