Biuletyn Informacji Publicznej Uniwersytetu Przyrodniczego we Wrocławiu

Job position: PhD student

Requirements:
Concerning the scholarship for a phD. student, we will apply the general criteria formulated by the National Science Centre in Poland and the following additional criteria:

• Candidate must hold a Master’s degree in veterinary medicine, microbiology, biotechnology, or in a related field or be a student in the last year of the Master's degree program in one of the aforementioned fields,
• Experience in laboratory work:

1. Molecular biology skills: PCR methods, DNA electrophoresis, DNA/RNA extraction, plasmid isolation, generation of deletion mutants, cloning,
2. Cell biology skills: in vitro culture of cell lines, adhesion, and invasion assay,
3. Microbiology skills: cultivation of bacteria, adhesion, and invasion assays;
4. Protein skills: protein purification, SDS PAGE, Western blot, ELISA,
5. Ability to work with animals in a research setting.

• Additional requirements:

1. Sound understanding of molecular mechanisms of bacterial pathogenesis (with particular emphasis on the Salmonella genus)
2. Basic proficiency in the use of biological databases and online resources/tools •
3. Good written and spoken English communication skills

Responsibilities:

It is expected that phD student will actively research the area related to the research grant, towards writing a phD. thesis related to the project’s topic. This will be done alongside and under the supervision of the Principal Investigator.
The tasks will include:

• Generation of Salmonella mutants (single, double, triple),
• Characterization of generated mutants,
• Cell line adhesion and invasion assays with the use of Salmonella,
• Participation in in vivo studies utilizing a mouse model of Salmonella infection,
• Real-time expression analysis using fluorescence techniques,
• Analysis of genes expression levels,
• Analysis of proteins expression levels,
• Data interpretation and statistical analysis,
• Attendance at national and international conferences (oral and poster presentation),
• Preparation of the research manuscripts based on results of investigations,
• regular work at the Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences.

Required documents:
Candidates should submit the following documents:

• scientific CV in English containing:
  - description of research experience,
  - list of publications - also those in preparation,
  - list of conference presentations,
  - list of awards and achievements regarding scientific work,
  - motivation letter describing research competencies and motivation to engage in the project,
  - scan of a document confirming receipt of the Master's degree or fifth-year student status,
  - confirmation of B2 English level.

We offer:

• doctoral scholarships for 48 months,
• doctoral scholarships shall amount to PLN 5,000 per month (gross) in the first two years and 6000 PLN per month (gross) in the last two years,
• financial support for conducting studies that are research tasks in the project and attending conferences to present the results of the project.

Eligibility criteria
Formal criteria:

• competencies to perform specific tasks in a research project (70% of the final score),
• publication and scientific achievement track record, including publications in renowned scientific papers/ magazines (30% of the final score).

Selection process:
Please submit your documents: krzysztof.grzymajlo@upwr.edu.pl

Application deadline: 28.07.2023 r.
Competition results announced: 15.08.2023 r.
Date of project commencement: 01.10.2023 r.

Competition committee:

• Krzysztof Grzymajło, Ph.D. - Chair of the Committee,
• Aleksandra Pawlak, Ph.D. – Member of the Committee,
• Ewa Wałecka-Zacharska, Ph.D. – Member of the Committee.

After reviewing applications, the highest-ranked candidates may be invited for an interview.

Additional information:

This offer is accompanied by a scholarship competition under the aegis of the National Science Centre PRELUDIUM BIS project number 2022/47/O/NZ6/01128, “Swim and adhere – regulation of Salmonella’s virulence factors expression and its impact on infection”, under the supervision of dr hab. Krzysztof Grzymajło, PI.

Description of the research project:
Salmonella infections are a serious epidemiological issue worldwide, globally affecting about 200 million people and resulting in 60,000 fatal cases per year. At the same time, it is a serious economic problem with an overall estimated economic burden that could be as high as 3 billion EURO per year only in European Union.
The pathogenesis of Salmonella infection is a multistage process of interactions between bacteria and host, focused on reaching, attaching, and invading the host cells. The expression of crucial virulence factors responsible for those events, like flagella, fimbriae, and secretion systems respectively, in the context of the host environment, determine the potential success of the infection. The first two, flagella and fimbriae are considered crucial for the initial stages of infection. Flagella, long helical filaments attached to rotary motors, enable bacteria to swim in liquids and swarm over the surface, enabling reaching the invasion site as well as in biofilm formation. Flagella are composed of three basic elements: the basal body, hook, and filament. The filament is made of two different antigenic proteins, FliC and FljB, that are coordinately regulated in the so-called phase variation mechanism. Among Salmonella’s adhesive structures, type 1 fimbriae (T1F) are one of the most extensively studied. T1F are relatively long, rod-shaped structures composed primarily of FimA monomers and with a lectin-like protein, FimH, present at the tip, which is directly responsible for binding to host cells. Despite numerous studies focused on the role and regulation of the initial stages of Salmonella’s virulence factors, there is no sufficient data on how flagellins and T1F are regulated - when and for how long expressed during Salmonella infection. The role and significance of T1F-flagella cross-talk remain relatively unknown. What is more, there is no detailed data on global transcription regulators impacting T1F and flagella expression. Therefore, the major research objective of this project is to explain the mutual regulation of Salmonella’s virulence factors (flagella and T1F) that plays a role in the first stages of Salmonella infection.
Our preliminary studies revealed that T1F expression is dependent on growth conditions and correlates with adhesion level to intestinal epithelial cells. Deletion of the entire T1F operon significantly reduced adhesion and invasion of porcine and mice intestinal cells. What is more, the knock-out of T1F operon regulatory genes impacts flagella expression level. Both fliC and fljB genes encoding flagellins, as well as direct regulators of flagella expression (fliA and fliZ) were expressed significantly lower compared to the WT strain.
Taking it all into consideration, we decided to propose a research project investigating the cross-talk between the adhesive and motility structures of Salmonella during the first and crucial stages of the pathogen infection. We are planning to make the new experimental models which allow us for the first time real-time tracking of Salmonella’s virulence factor expression through the course of infection. In addition, we will manipulate the level of T1F and flagella expression, by the construction of mutants with high constant expression and inducible expression of those structures. We will investigate the adhesion and invasion levels of Salmonella mutants using various cellular models. What is more, we will use an established mice model allowing persistent Salmonella infection to verify our in vitro results in the pathogen’s natural environment.
We expect, that the realization of this grant proposal will improve our current understanding of Salmonella pathogenesis, which can further lead to the improvement of current methods of salmonellosis prevention and treatment. This is especially relevant because taking into account Salmonella’s survival ability in variable conditions and adaption to new niches, together with the growing antibiotic resistance of microbes all over the world, salmonellosis prevention and treatment become more and more difficult. The results of this project might be used as a starting point for the development of prevention or alternative treatment therapy for bacterial infections.

The Information Clause for candidates for employees participating in the recruitment process can be found at University website.

W celu otrzymania dodatkowych informacji dot. rozstrzygnięcia konkursu prosimy o kontakt pod adresem: centrum.rozliczania@upwr.edu.pl.