Random Insertional Mutagenesis in Fungal Genomes to Identify Virulence Factors

Author(s):  
Parthasarathy Santhanam
2005 ◽  
Vol 187 (9) ◽  
pp. 3255-3258 ◽  
Author(s):  
Pascale Bourhy ◽  
Hélène Louvel ◽  
Isabelle Saint Girons ◽  
Mathieu Picardeau

ABSTRACT The recent availability of the complete genome sequences of Leptospira interrogans, the agent of leptospirosis, has allowed the identification of several putative virulence factors. However, to our knowledge, attempts to carry out gene transfer in pathogenic Leptospira spp. have failed so far. In this study, we show that the Himar1 mariner transposon permits random mutagenesis in the pathogen L. interrogans. We have identified genes that have been interrupted by Himar1 insertion in 35 L. interrogans mutants. This approach of transposon mutagenesis will be useful for understanding the spirochetal physiology and the pathogenic mechanisms of Leptospira, which remain largely unknown.


2021 ◽  
Vol 23 (1) ◽  
pp. 400
Author(s):  
Alexander Yemelin ◽  
Annamaria Brauchler ◽  
Stefan Jacob ◽  
Andrew J. Foster ◽  
Julian Laufer ◽  
...  

Diseases caused by dimorphic phytopathogenic and systemic dimorphic fungi have markedly increased in prevalence in the last decades, and understanding the morphogenic transition to the virulent state might yield novel means of controlling dimorphic fungi. The dimorphic fungus Z. tritici causes significant economic impact on wheat production, and yet the regulation of the dimorphic switch, a key first step in successful plant colonization, is still largely unexplored in this fungus. The fungus is amenable to suppression by fungicides at this switch point, and the identification of the factors controlling the dimorphic switch provides a potential source of novel targets to control Septoria tritici blotch (STB). Inhibition of the dimorphic switch can potentially prevent penetration and avoid any damage to the host plant. The aim of the current work was to unveil genetic determinants of the dimorphic transition in Z. tritici by using a forward genetics strategy. Using this approach, we unveiled two novel factors involved in the switch to the pathogenic state and used reverse genetics and complementation to confirm the role of the novel virulence factors and further gained insight into the role of these genes, using transcriptome analysis via RNA-Seq. The transcriptomes generated potentially contain key determinants of the dimorphic transition.


2012 ◽  
Vol 6 (1) ◽  
pp. 14-17
Author(s):  
Jabin Akhter ◽  
Shaheda Anwar ◽  
Sharmeen Ahmed

Urinary tract infection caused by Enterococci has become frequent occurrences in health care settings. Currently they emerged with increasing resistance to multiple antibiotics.  Haemolysin, gelatinase and biofilm production are some markers that have been proposed as possible Enterococcal virulence factors. In view of the increasing importance of Enterococcal infection, the present study was designed to isolate and identify the Enterococci to the species level from urine of urinary tract infection patients and to investigate their possible virulence factors. Biofilm was detected on polystyrene microtitre plate to see the adherence of microorganism. Haemolysin production and gelatin hydrolysis detected by standard microbiological method. Fifty nine enterococcal isolates were speciated by conventional microbiological method and examined for their ability to form biofilm by microtitre plate assay. In this study, biofilm formations by Enterococci were found in 83.33% isolates from catheterized and 56.09% from non-catheterized patients. Aong them, E.faecalis & 50% E.faecium produced biofilm. About 43.63% E.faecalis & 10% E.faecium produced haemolysin and only one isolate were found to be gelatinase positive. Frequency of virulence factors (VFs) in combination was observed in this study. Two VFs (haemolysin and biofilm) were observed in 27.11% in combination and 3 VFs ( haemolysinm biofilm and gelatinase) were present in 1.69% isolates. These results suggest that although there may not be an absolute role for individual virulence determinants in infectivity, combinations of factors may play a role in allowing a biofilm infection to be more resistant to therapy.DOI: http://dx.doi.org/10.3329/bjmm.v6i1.19361 Bangladesh J Med Microbiol 2012; 06(01): 14-17


2014 ◽  
Vol 5 (1) ◽  
pp. 17-25
Author(s):  
Agnieszka Sikora ◽  
Małgorzata Wójtowicz-Bobin ◽  
Anna Sikora ◽  
Maria Kozioł-Montewka ◽  
Dagmara Strzelec - Nowak
Keyword(s):  

2017 ◽  
Vol 13 (3) ◽  
pp. 206-221
Author(s):  
Hadi Rahman Rasheed Al-Taai ◽  
◽  
Zainab Mohammed Hameed ◽  
Izdehar Mohammed Jasim

Infectio ro ◽  
2018 ◽  
Vol 2 (54) ◽  
pp. 27
Author(s):  
Mădălina Preda ◽  
Alina Maria Holban ◽  
Lia-Mara Diţu ◽  
Coralia Bleotu ◽  
Mădălina-Maria Muntean ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document