Category Archives: Salmonella

Introducing DR. Ana Carolina Ritter, PhD! Moving from PhD student to Post Doctoral Fellow

So you can’t wait to finish your PhD.  The years have been slowly slugging by.  It seems you have been at it for eternity…  And then BAM!!! You are done.  It seems it has come all at once.  So what comes next? What comes after the PhD is completed?  And importantly, now that you have finished (which is what you have been waiting for), it may be hard to know how to move on or what to do next.  I HAVE BEEN THERE. And so has Ana Carolina.

Ana last wrote of her interesting PhD research on Salmonella, telling us how she was able to study and conduct her lab work in both Italy and in her native Brazil.  Now Ana updates us with her exciting news that she has received her PhD.  She also shares how she navigated the difficult road from PhD to landing a postdoctoral fellowship in Bologna, Italy.

Good Luck Ana!


Italy, I’m coming!

Hello! Good news, I’m going back to Italy … To do the postdoctoral research, this time in Bologna!

In my last blog post, I wrote a little bit about my experience completing part of my PhD at the University of Sassari… Since then, I have completed my PhD and the desire to return to Italy increased!

AnaPhD Talk

Ana’s PhD Seminar in Brazil

Therefore, while completing my doctorate, I sought out a group conducting strong research in food microbiology in Italy to do my postdoctoral research. After searching through PubMed, I found some papers published by the group led by Professor Maria Elisabetta Guerzoni.  I was very interested in the research they perform at the University of Bologna, more precisely in the Distal.  I contacted Professor Guerzoni and we were extremely well matched.

Upon receipt of her acceptance, I applied for a scholarship from a Brazilian funding agency for research, called “National Counsel of Technological and Scientific Development” (CNPq)1.  I outlined a project where I proposed working with new technology for disinfection of food, called Gas plasma2.  In late September I received a positive response from the Brazilian government, and will embark for Bologna in January 2013! Very cool huh?

Currently, it is exciting times for research in Brazil as the government is supporting researchers in bringing new technologies to Brazil by funding global travel for scientific education.  This initiative supports the development of competent professionals, through the granting of many scholarships to enable researchers to study in top universities worldwide.

I’m very excited as I am going through a new experience both in my personal life and academic life. And I hope that this partnership with the University of Bologna allows me to publish work as was the case happened with the University of Sassari3… And of course, I’ll be closer the Central Office of JIDC and old friends.

See you!


2: Ragni, A., Berardinelli,A.,, Vannini, L., Montanari, C, Sirri, F., Guerzoni, M.B., Guarnieri, A. Non-thermal atmospheric gas plasma device for surface decontamination of shell eggs. Journal of Food Engineering 100 (2010) 125–132.

3: Ritter, A. C., Bacciu, D., Santi, L., Silva, W.O.B, Vainstein, M. H., Rubino, S., Uzzau, S., Tondo,E.C. Investigation of rpoS and dps genes in Sodium Hypochlorite Resistance of Salmonella Enteritidis SE86 Isolated from Foodborne Illness Outbreaks in Southern Brazil. Journal of Food Protection. Journal of Food Protection. , v.75, p.437 – 442, 2012.


Ana’s PhD Graduation Celebration


Filed under Brazil, Countries, Infectious Disease, Postcards, Salmonella

A Plague of Bones: Conference!

Without a doubt, my favourite research project I have ever been a part of is the ancient Pathogens project. This was my research focus during my Visiting Professorship at the University of Sassari, Sardinia, Italy in 2010. This was my Indian Jones moment, except the treasure was not rare artifacts but the discovery of ancient pathogens.

In Sardinia there is an abundance of ancient and medieval mass graves (see burial map).  Although these mass graves data back more than 3,000 years, the reason for the mass grave construction still remains a mystery.  Thereby a fascinating scientific problem exists:  What did these people buried together die from?

Archeology of Sardinia

We hypothesized that by sequencing the nonhuman DNA extracted from the bones and teeth of the victims in the mass graves, we could identify a pathogen that may have infected these people and caused their death.   Our list of pathogenic suspects that may have caused death included Yersinia pestis, Salmonella enterica, Bacillos anthracis, Mycobacterium tuberculosis.  This mode of attack, sequencing ancient DNA to determine cause of death, is not new and previous examples include identification of Salmonella enterica enterica serovar Thypi as the causative agent of the ancient plague of Athens in 430 BC [1] and Yersinia pestis as the agent of the Black Plague [2–4] although the later has been disputed [5].   Importantly, mass graves are commonly devised during a disease outbreak to limit the spread of disease, as in Europe during the Black Plague.  Therefore, we speculated that the people buried together in the mass graves of Sardinia died of the same cause, a disease epidemic.  By identifying and studying the causative agent of ancient plagues, we hope to learn about the evolving nature of human and animal modern pathogens so that we can model current and future epidemics.

Since I left Sardinia and my little project, the ancient Pathogen Project has grown enormously.  And that brings us to the announcement of the Ancient Pathogens meeting hosted by Professor Salvatore Rubino in Sardinia, Italy, in September.  The conference is sponsered by JIDC, University Health Network, Shantou University Medical School, Immune Diagnostics and Research, Comune Di Stintino, University of Sassari. This is an exciting opportunity!

Mass grave excavation in Alghero, Sardinia

Titled Mummies, Bones, and Ancient Pathogens, the conference will take place 7-8 September 2012, in Stintino, Sardinia, Italy, at the STINTINO Palazzo Comunale. Over the course of the two days, four sessions on “Archaic and Modern Genomes”, “Evolutionary Medicine, Ancient Pathogens and Pathologies”, “Ancient Pathogens”, and “Bioarchaeology of Sardinia and Sicily” will be held. Several of Europe’s foremost researchers in the fields of Archaeology, Bioarchaeology, the History of Medicine, and Ancient Pathogens are featured speakers, including Prof. Carsten Pusch of the Institute of Human GeneticsUniversity of Tübingen, Germany;  Prof. Bernardino Fantini University of Geneva, Switzerland; Prof. Marco Milanese, University of Sassari; Susanna Sawyer University of Tübingen, Germany; Prof. Raffaella Bianucci University of Turin; Prof. Paolo Francalacci University of Sassari; Prof. Marco Rendeli, University of Sassari; Elisabetta Garau, Unversity of Sassari; Rossella Filigheddu, University of Sassari; and Dr. Alberto Leo Shantou University to name a few. Just to tantalize you, here are some titles of the exciting presentations:

“Archaic Genomes: A Story Written in Neanderthal and Denisova DNA”

“Placing the sequence of “Ötzi the Iceman” in the high resolution Y chromosome phlylogeny by whole genome sequencing”

“Cancer and Infectious Diseases: the Challenge of Soft Tissue Paleopathology”

“Vector-Borne Diseases in Ancient Human Remains”

“The Sicily Mummy Project”

“First Insights into the Metagenome of Ancient Egyptian Mummies Using Next Generation Sequencing”

“Sequencing DNA from Ancient Seeds with Medicinal Properties”

For more information including registration, please visit the conference website  or email Prof. Salvatore Rubino at rubino(at)uniss(dot)it

Reference List

    1.    Papagrigorakis MJ, Yapijakis C, Synodinos PN, Baziotopoulou-Valavani E (2006) DNA examination of ancient dental pulp incriminates typhoid fever as a probable cause of the Plague of Athens. Int J Infect Dis 10: 206-214. S1201-9712(05)00178-5 [pii];10.1016/j.ijid.2005.09.001 [doi].

2.    Raoult D, Aboudharam G, Crubezy E, Larrouy G, Ludes B, Drancourt M (2000) Molecular identification by “suicide PCR” of Yersinia pestis as the agent of medieval black death. Proc Natl Acad Sci U S A 97: 12800-12803. 10.1073/pnas.220225197 [doi];220225197 [pii].

3.    Drancourt M, Aboudharam G, Signoli M, Dutour O, Raoult D (1998) Detection of 400-year-old Yersinia pestis DNA in human dental pulp: an approach to the diagnosis of ancient septicemia. Proc Natl Acad Sci U S A 95: 12637-12640.

4.    Drancourt M, Raoult D (2004) Molecular detection of Yersinia pestis in dental pulp. Microbiology 150: 263-264.

5.    Gilbert MT, Cuccui J, White W, Lynnerup N, Titball RW, Cooper A, Prentice MB (2004) Absence of Yersinia pestis-specific DNA in human teeth from five European excavations of putative plague victims. Microbiology 150: 341-354.


Filed under Countries, Events, Infectious Disease, JIDC News, News, Salmonella, Tuberculosis, Yersinia pestis

Ana: Salmonella in Sardinia

I am please to present a Postcard written by the lovely Ana Carolina!  Ana is a microbiologist from Brazil who carried out part of her PhD in Sardinia, Italy studying salmonella.  I was lucky enough to work in Sardinia at the same time as Ana Carolina while I was completing my Visiting Professorship at the University of Sassari.  Ana works incredibly hard but always with a smile on her face.  It was a delight to see her everyday. I am happy to call Ana a colleague and a friend!

I went to Sardinia!

In 2008 I started my PhD in food microbiology at the Federal University of Rio Grande do Sul (UFRGS), in Porto Alegre, Brazil. It was a moment of transition, because I did my master’s degree working with mycotoxins and now I decided to work with Salmonella. I was accepted to a group that has studied the occurrence of outbreaks of salmonellosis in the state of Rio Grande do Sul (RS) (southern Brazil) for 10 years, the Laboratory of Food Microbiology of the ICTA/UFRGS.


This research group had already made several discoveries regarding Salmonella Enteritidis (S. Enteritidis).  In previous work done in the Laboratory of Food Microbiology, the spvR gene (Salmonella plasmid virulance)was identified in 82.7% of S. Enteritidis infections involved in food poisoning cases which occurred in RS from 1999 to 2000 [1] . These isolates were also characterized according to their antibiotic resistance, and it was shown that there was a high percentage of sensitivity to most of the drugs tested [1] . Oliveira et al. [2] demonstrated that strains of S. Enteritidis isolated from these outbreaks which occurred in RS in 2001 and 2002 showed similar resistance profiles as the lines of the preceding period.  Interestingly, it was identified that one strain of S. Enteritidis was involved in more than 95% of the salmonellosis cases which occurred in RS [2]. Importantly, other work from the laboratory evaluated the resistance of S. Enteritidis SE86 to disinfectants commonly used in food industries [2]. It was concluded from this work that peracetic acid, sodium hypochlorite and quaternary ammonium were able to inactivate S. Enteritidis SE86; however, this strain was more resistant to the concentration of 200 ppm sodium hypochlorite (commonly used in Brazil).

Salmonella by

Continuing the investigation into the strains of S. Enteritidis which are responsible for salmonellosis and acid resistance in RS, my PhD project aims to investigate the expression of resistance genes which may contribute to the involvement of this predominant strain of S. Enteritidis in food in Brazil. That was the part of the thesis that took me to the Laboratorio di Microbiologia at Univesrsità degli Studi di Sassari.


So, with the desire of live outside Brazil and to enrich the Brazilian science, I went to Sardinia or Sardegna, Italy.  Sardinia is a large Island in the Mediterranean Sea.


To realize this dream, I sent emails to  Professore Salvatore Rubino (Editor-in-Chief of JIDC) and Professore Sergio Uzzau, asking if I could perform one year of research in their laboratory. After their positive response, I applied for a scholarship to Capes, a Brazilian funding agency for research. The result was one year living in Sassari (2009 to 2010), developing my thesis.

Landscape of Sardinia

Landscape of Sardinia by Travel around the World

In Sardinia genetic modifications in the Brasilian S. Enteritidis (strain SE86) were preformed. With the help of Doctoressa Donatella Bacciu, we performed knockout techniques [3] and epitope tagging [4] in four different genes to check the expression of these strain’s forward acidity and high temperatures, results which I am currently writing up.

It was an incredible experience! Sardinia has breathtaking landscapes, incredible history and very nice people. The university gave me all necessary support for my research; with great colleagues guiding me … I learned a lot, both inside and outside the laboratory. I returned to my country with lots of knowledge: the language, the laboratory techniques, dear friends. I love Sardinia!

 Today I am writing the articles and the thesis, because I have to finish my PhD

The Italian Island of Sardinia by

by March 2012.

 Post doc? Why not? Science takes us to places that we never dreamed… 


 Ana is 31 years old. She studied biology (2000 until 2004), then did a two year master degree ( between 2005 and 2007) working with  Aspergillus flavus (food microbiology). In 2008, she started her PhD (food microbiology) at the Federal University of Rio Grande do Sul (UFRGS) in Porto Alegre, Rio Grande do Sul, Brazil. Ana’s story to be post in Portuguese soon!



Silvia, Francesca, me, Massimo and Donatella: friends and colleagues of the microbiology laboratory in SardiniaAna in Sardinia, ItalyAna in Sardinia

Amazing food and wine

Reference List


    1.    Geimba MP, Tondo EC, de Oliveira FA, Canal CW, Brandelli A (2004) Serological characterization and prevalence of spvR genes in Salmonella isolated from foods involved in outbreaks in Brazil. J Food Prot 67: 1229-1233.

    2.    de Oliveira FA, Brandelli A, Tondo EC (2006) Antimicrobial resistance in Salmonella enteritidis from foods involved in human salmonellosis outbreaks in southern Brazil. New Microbiol 29: 49-54.

    3.    Datsenko KA, Wanner BL (2000) One-step inactivation of chromosomal genes in Escherichia coli K-12 using PCR products. Proc Natl Acad Sci U S A 97: 6640-6645. 10.1073/pnas.120163297 [doi];120163297 [pii].

    4.    Uzzau S, Figueroa-Bossi N, Rubino S, Bossi L (2001) Epitope tagging of chromosomal genes in Salmonella. Proc Natl Acad Sci U S A 98: 15264-15269. 10.1073/pnas.261348198 [doi];261348198 [pii].


Filed under Postcards, Salmonella