scholarly journals Sequencing of Gliotoxin Genes in Clinical and Environmental Aspergillus fumigatus isolates in Iraq

2018 ◽  
Vol 12 (1) ◽  
pp. 33-39
Author(s):  
Russel S. Abdulhadi ◽  
Nemat J. Abdulbaqi

Gliotoxin is an important virulence factors in Aspergillus fumigatus. The biosynthesis of this mycotoxin is regulated and expressed by the presence of gliP genes. This study aimed to identify Aspergillus fumigatus isolates in clinical and environmental sources with glip genes using conventional PCR and sequence. To achieve this, DNA was isolated from twenty A. fumigatus isolates using commercial kit. The range of the DNA extracted was 65-210 ng/μl with a purity of 1.5-1.9. Species identification of the A. fumigatus isolates was achieved to a high specificity by using tailored primer. The results showed that all isolates had positive results to the primer and all isolates were able to produce gliotoxin. PCR detected the gliotoxin genes, glip in five isolates. The five PCR product samples were sent for sequence analysis and 25 µl (10 pmol) from the forward primer. The results of all the samples  indicated have a  single band of the desired product of gliP gene of A.fumigatus and the samples sent for sequencing related to molecular weight 190 bp.

Virulence ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 818-834
Author(s):  
Marie-Fleur Durieux ◽  
Élise Melloul ◽  
Sana Jemel ◽  
Lolita Roisin ◽  
Marie-Laure Dardé ◽  
...  

2014 ◽  
Vol 80 (8) ◽  
pp. 2484-2492 ◽  
Author(s):  
Hedwig-Annabell Schild ◽  
Sebastian W. Fuchs ◽  
Helge B. Bode ◽  
Bernd Grünewald

ABSTRACTThe spore-forming bacteriumPaenibacillus larvaecauses a severe and highly infective bee disease, American foulbrood (AFB). Despite the large economic losses induced by AFB, the virulence factors produced byP. larvaeare as yet unknown. To identify such virulence factors, we experimentally infected young, susceptible larvae of the honeybee,Apis mellifera carnica, with differentP. larvaeisolates. Honeybee larvae were rearedin vitroin 24-well plates in the laboratory after isolation from the brood comb. We identified genotype-specific differences in the etiopathology of AFB between the tested isolates ofP. larvae, which were revealed by differences in the median lethal times. Furthermore, we confirmed that extracts ofP. larvaecultures contain low-molecular-weight compounds, which are toxic to honeybee larvae. Our data indicate thatP. larvaesecretes metabolites into the medium with a potent honeybee toxic activity pointing to a novel pathogenic factor(s) ofP. larvae. Genome mining ofP. larvaesubsp.larvaeBRL-230010 led to the identification of several biosynthesis gene clusters putatively involved in natural product biosynthesis, highlighting the potential ofP. larvaeto produce such compounds.


2016 ◽  
Vol 473 (9) ◽  
pp. 1203-1213 ◽  
Author(s):  
Yong-Sung Park ◽  
Ju-Yeon Kim ◽  
Cheol-Won Yun

Aspergillus fumigatus is an opportunistic fungal pathogen for immunocompromised patients, and genes involved in siderophore metabolism have been identified as virulence factors. Recently, we identified the membrane transporters sit1 and sit2, which are putative virulence factors of A. fumigatus; sit1 and sit2 are homologous to yeast Sit1, and sit1 and sit2 gene expression was up-regulated after iron depletion. When expressed heterologously in Saccharomyces cerevisiae, sit1 and sit2 were localized to the plasma membrane; sit1 efficiently complemented ferrichrome (FC) and ferrioxamine B (FOB) uptake in yeast cells, whereas sit2 complemented only FC uptake. Deletion of sit1 resulted in a decrease in FOB and FC uptake, and deletion of sit2 resulted in a decrease in FC uptake in A. fumigatus. It is of interest that a sit1 and sit2 double-deletion mutant resulted in a synergistic decrease in FC uptake activity. Both sit1 and sit2 were localized to the plasma membrane in A. fumigatus. The expression levels of the sit1 and sit2 genes were dependent on hapX under low-but not high-iron conditions. Furthermore, mirB, and sidA gene expression was up-regulated and sreA expression down-regulated when sit1 and sit2 were deleted. Although sit1 and sit2 failed to affect mouse survival rate, these genes affected conidial killing activity. Taken together, our results suggest that sit1 and sit2 are siderophore transporters and putative virulence factors localized to the plasma membrane.


2018 ◽  
Vol 27 (4) ◽  
pp. 505-513 ◽  
Author(s):  
Anna Cláudia Baumel Mongruel ◽  
Priscila Ikeda ◽  
Keyla Carstens Marques de Sousa ◽  
Jyan Lucas Benevenute ◽  
Margarete Kimie Falbo ◽  
...  

Abstract Arthropod-borne pathogens are medically important because of their ability to cause diseases in their hosts. The purpose of this study was to detect the occurrence of Ehrlichia spp., piroplasmids and Hepatozoon spp. in dogs with anemia and thrombocytopenia in southern Brazil. EDTA-whole blood was collected from 75 domestic dogs presenting anemia or/and thrombocytopenia from Guarapuava, state of Paraná, Brazil. DNA samples were subjected to conventional PCR assays for Ehrlichia spp. (dsb), piroplasmids (18S rRNA) and Hepatozoon spp. (18S rRNA), followed by sequencing and phylogenetic analyses. Among the 75 dogs, one (1.33%) was positive for Hepatozoon sp. and six (8%) were positive for piroplasmids in 18S rRNA cPCR assays. None of the dogs showed positive results in Ehrlichia spp.-cPCR targeting dsb gene. The phylogenetic analyses revealed that three piroplasm sequences were clustered with Rangellia vitalii, while one sequence was grouped with B. vogeli. The only sequence obtained from Hepatozoon spp.-PCR protocol was pooled with H. canis. Therefore, there is urgent need for differential molecular diagnosis of the two piroplasm species cited as etiological agents in clinical cases of canine hemoparasitic diseases, given the higher pathogenic potential of R. vitalii than of B. vogeli.


2003 ◽  
Vol 32 (6) ◽  
pp. 647-654 ◽  
Author(s):  
T Anthony ◽  
K Chandra Raj ◽  
A Rajendran ◽  
P Gunasekaran

Author(s):  
Ilham A Bunyan ◽  
Israa K Obais

The present study included the detection ofsome virulence factorsof Aeromonas hydrophila under molecular level to clinical isolates were taken from patients suffering from diarrhea during the period from July (2017) to October (2017). Molecular detection of Hemolysin gene (ahh) was done for all isolates. The results showed that all isolates (100%) gave positive results for this virulence gene. the positive results were detected by the presence of (130) bp bands when compared with allelic ladder. The genomic DNA of the samples was extracted and bands were observed by performing agarose gel electrophoresis. When PCR was performed,results clearly indicate that all isolated organisms contained serine protease gene and all the amplified products produced a band at the level of (900 bp) when compared with the allelic ladder. Molecular detection of this gene was carried out by using a specific PCR primer were done by comparison with allelic ladder which gave a (309bp) It was found that (Aerolysin) gene present in (12) (75%) of the positive samples. Lip gene was also detected in A. hydrophila samples and found that all 16 samples (100%) gave positive results to this gene which gave molecular length (382) bp. Molecular study was carried out to show the sequence identity of cytotonic enterotoxins gene in Aeromonas spp. to that in A. hydrophila. Analysis of the A. hydrophila genome revealed a number of a putative virulence factors,including a gene that heat-labile cytotonic enterotoxin (alt). Our study showed that all (16) isolates (100%) gave positive results to this gene,which gave molecular length (442)bp. Molecular detection of cytotonic enterotoxins gene (ast) was done for (16) A. hydrophila isolates and the results showed that all isolates have this gene (100%). The positive results for (ast) virulence were detected by the presence of (331) bp band compared with allelic ladder.


1985 ◽  
Vol 63 (10) ◽  
pp. 2262-2266 ◽  
Author(s):  
A. V. Arjunwadkar ◽  
S. Raghupathi Rami Reddy

Arginine kinase in claw muscle extracts of the scorpion, Palamneus phipsoni, was characterized. The enzyme, with a pH optimum of 8.5 in the direction of phosphoarginine synthesis, showed activation by Mg2+, high specificity towards L-arginine as the guanidino substrate, slight inhibition by high concentrations of L-arginine and ATP, and a molecular weight of 33 500. On polyacrylamide gel electrophoresis at pH 8.3 the enzyme migrated to the anode as a single molecular species. In addition to the claw muscle, the enzyme activity was also found to be present in the heart, alimentary canal, hepatopancreas, and nervous system. In general, scorpion muscle arginine kinase appears to be similar in its properties to the enzyme from other arthropods.


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.


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