scholarly journals Modified nucleotides m2G966/m5C967 of Escherichia coli 16S rRNA are required for attenuation of tryptophan operon

2013 ◽  
Vol 3 (1) ◽  
Author(s):  
Irina V. Prokhorova ◽  
Ilya A. Osterman ◽  
Dmitry E. Burakovsky ◽  
Marina V. Serebryakova ◽  
Maria A. Galyamina ◽  
...  
1997 ◽  
Vol 179 (14) ◽  
pp. 4457-4463 ◽  
Author(s):  
G A Cangelosi ◽  
W H Brabant

1981 ◽  
Vol 9 (24) ◽  
pp. 6647-6668 ◽  
Author(s):  
C. Yanofsky ◽  
T. Platt ◽  
I.P. Crawford ◽  
B.P. Nichols ◽  
G.E. Christie ◽  
...  

2020 ◽  
Author(s):  
Liu Wen-qiang ◽  
Xia Nan ◽  
Zhang Jing-wen ◽  
Wang Ren-hu ◽  
Jiang Gui-miao

ABSTRACTObjectiveThe aim of this study was to identify the biological features, influence factor and Genome-wide properties of pathogenic donkey Escherichia coli (DEC) isolates associated with severe diarrhea in Northern China.MethodsThe isolation and identification of DEC isolates were carried out by the conventional isolation、automatic biochemical analysis system、serotype identification、16S rRNA test、animal challenge and antibiotics sensitivity examination. The main virulence factors were identified by PCR. The complete genomic re-sequence and frame-sequence were analyzed.Results216 strains of DEC were isolated from diarrhea samples, conforming to the bacterial morphology and biochemical characteristics of E.coli. The average size of the pure culture was 329.4 nm×223.5 nm. Agglutination test showed that O78 (117/179, 65.4%) was the dominant serotype and ETEC(130/216, 60.1%) was the dominant pathogenic type. Noticeable pathogenic were observed in 9 of 10 (90%) randomly selected DEC isolates caused the death of test mice (100%, 5/5) within 6h∼48h, 1 of 10 (10%) isolates caused the death of test mice (40%, 2/5) within 72h. Our data confirmed that DEC plays an etiology role in dirarrea/death case of donkey foal. Antibiotics sensitivity test showed significant susceptibility to DEC isolates were concentrated in Nor、EFT、ENR、CIP and AMK,while the isolates with severe antibiotic resistance was AM、TE、APR、FFC、RL and CN. Multi-drug resistance was also observed. A total of 15 virulence gene fragments were determined from DEC(n=30) including OMPA (73%), safD (77%), traTa (73%), STa(67%), EAST1 (67%), astA (63%), kspII (60%), irp2 (73%), iucD (57%), eaeA (57%), VAT (47%), iss (33%), cva (27%), ETT2 (73%) and K88 (60%) respectively. More than 10 virulence genes from 9 of 30(30%) DEC strains were detected, while 6 of 30(20%) DEC strains detected 6 virulence factors. phylogenetic evolutionary tree of 16S rRNA gene from different isolates shows some variability. The original data volume obtained from the genome re-sequencing of DEC La18 was 2.55G and Genome framework sequencing was carried out to demonstrate the predicted functions and evolutionary direction and genetic relationships with other animal E.coli.ConclusionsThese findings provide firstly fundamental data that might be useful in further study of the role of DEC and provide a new understanding of the hazards of traditional colibacillosis due to the appear of new production models.


2003 ◽  
Vol 254 (1) ◽  
pp. 115-123 ◽  
Author(s):  
José M. Igual ◽  
Angel Valverde ◽  
Raúl Rivas ◽  
Pedro F. Mateos ◽  
C. Rodríguez-Barrueco ◽  
...  

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5470 ◽  
Author(s):  
Elif Bozcal ◽  
Vahap Eldem ◽  
Sohret Aydemir ◽  
Mikael Skurnik

Background Extraintestinal pathogenic Escherichia coli (ExPEC) is an important bacterium and responsible for many bloodstream infections, including urinary tract infections and even fatal bacteremia. The aim of this research was to investigate whether ExPEC strains isolated from Turkish blood cultures have a relationship between 16S rRNA based phylogenetic clusters and antibiotic resistance profiles, virulence factors or clonal lineages. Methods Phenotypically identified ExPEC blood culture isolates (n = 104) were included in this study. The 16S rRNA partial sequence analysis was performed for genotypic identification of ExPEC isolates. Antibiotic susceptibility and Extended-Spectrum β-Lactamase testing of isolates were performed. Phylogenetic classification (A, B1, B2 and D), Multi Locus Sequence Typing analysis and virulence-associated genes were investigated. Results Based on 16S rRNA partial sequence analysis, 97 out of 104 (93.26%) ExPEC isolates were confirmed as E. coli. Ampicillin (74.22%) and cefuroxime axetil (65.97%) resistances had the highest frequencies among the ExPEC isolates. In terms of phylogenetic classification of ExPEC, D (38.14%, 37/97) was the most prevalent group after A (29.89%, 29/97), B2 (20.61%, 20/97), and B1 (11.34%, 11/97). The sequence types of the 20 ExPEC isolates belonging to the B2 phylogenetic group were analyzed by Multi Locus Sequence Typing. Ten isolates out of 20 (50.0%) were identified as ST131. The other STs were ST95 (n = 1), ST14 (n = 1), ST10 (n = 1), ST69 (n = 1), ST1722 (n = 2), ST141 (n = 1), ST88 (n = 1), ST80 (n = 1), and ST998 (n = 1). Of the ST131 strains, six (60%, 6/10) represented serogroup O25. The most common virulence factor genes were serum resistance factor gene, traT (55.7%) aerobactin siderophore receptor and yersiniabactin encoding genes iutA (45.3%) and fyuA (50.5%), respectively. In addition, PAI (41.2%), iroN (23.7%), hlyA (15.4%), kpsII (13.4%), ompT (13.4%), papG (12.4%), iss (9.3%), cnf1 (7.2%), ibeA (2.06%), and sfaS (2.06%) genes were present in the ExPEC isolates. Conclusion The 16S rRNA-based phylogenetic relationship tree analysis showed that a large cluster was present among 97 ExPEC isolates along with related reference strains. There were 21 main clusters with 32 closely related subclusters. Based on our findings, different clonal lineages of ExPEC can display different antibiotic susceptibilities and virulence properties. We also concluded that virulence factors were not distributed depending on phylogenetic groups (A, B1, B2, and D). The ExPEC isolates belonging to the same phylogenetic group and sequence type could display different resistance and virulence characteristics.


2003 ◽  
pp. 115-123
Author(s):  
José M. Igual ◽  
Angel Valverde ◽  
Raúl Rivas ◽  
Pedro F. Mateos ◽  
C. Rodríguez-Barrueco ◽  
...  

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