University of Delaware

Department of Biological Sciences

BISC667: "Molecular Mechanisms of Pathogens"

Spring 2008

 

This course will introduce advanced topics in mechanisms of pathogenesis in relation to the primary scientific literature.

 

Suggested textbook: Bacterial Pathogenesis: A molecular approach by Salyers and Whitt (ASM Press).  In addition, the class will discuss all topics in relation to the primary scientific literature.  Notes for the class and the papers to be discussed will be found on Web CT. 

 

Coordinator:  Dr. E. Fidelma Boyd

Schedule: Monday/Wednesday  Room Wolf 318, 1.45pm - 3.00pm

 

Grading

            50%    Two cumulative one hour exam on course material (25% mid-term and                                    25% Final exam to give 50% total)

            20%    Two class presentations per student of research papers (10% each)

            20%    Four written critiques of research articles (5% each)

            10%    Class participation

 

Prerequisites: BISC 300 (or equivalent).  In addition, a working understanding of microbial molecular biology and microbial genetics is expected.  If you have any doubts about your preparation please discuss this with Dr. E. Fidelma Boyd the first week of class.

 

Professor:      E. Fidelma Boyd, Ph.D.                              

                        Department of Biological Sciences

                        328 Wolf Hall                                                

                        fboyd@udel.edu                   

 

Course policies:

 

Attendance: Attendance will not be taken and is not figured into the final grade.  However, students are responsible for all material covered in class (which may or may not be found in the materials posted on WebCt).

 

EXAMS:  Two cumulative one hour exams will be given to test your understanding of the material presented in lecture.  All exam questions are either short answer format or multiple choice questions.  Make-up exams will only be given under the most unusual and very rare circumstances (such as medical emergency or family crisis), which must be accompanied by documentation.  You must contact Dr. E. Fidelma Boyd in writing at least two days ahead of the exam to be missed, to stand any chance of being granted a make-up exam.

Presentations: There are four paper sets, with each student presenting twice during the semester. I will assign papers after the first week of class. Each paper set consists of four papers, and each student with be assigned two papers to present and two papers to write a critique on (see below for details on written critique).  When it is your turn to present, you should give 1) a short introduction to the topic, 2) major findings and 3) overall conclusions of how the research has advanced the field.  Then open the floor for discussion. 10 presentations plus 5 minutes of discussion.  Every student is expected to have read all papers and therefore participate actively in discussion.

During the discussion, you should make sure as presenter that everyone gets a chance to participate, and should also recognize when the discussion is dwelling on minor points or bogging down and pose questions that will get things back on track.

To present visual information as part of your presentation, you may use the chalkboard, overheads, PowerPoint (for Windows or Macintosh). If you are going to use PowerPoint, e-mail the file to me by 1 p.m. on the day of your presentation, and if possible, bring the file to class on a flash drive or CD as a backup in case the e-mail doesn't work.

Each presentation will be worth 10 percent of your grade (20 per cent total), based on the thoroughness of your preparation, your effective use of visual aids (note that "effective" does not mean "flashy"; sometimes a simple chalkboard drawing is all you need), and your ability at leading a discussion.

Papers: You are required to submit a critique of each paper set presented (4 in all), at the end of class on the day of the discussion of each paper set.  Each paper must be typed and at least one-and-a-half single-spaced pages long (maximum word count 1000) and must identify the major question or questions each paper was trying to answer, discuss how well the papers addressed their main questions, mention one or two good and bad points about each paper, and suggest further research. Points are awarded to papers with more opinions then papers that merely summarize the contents of papers.  These papers will count for 20 percent of your grade.  Remember, it is more difficult than you may think to write a synopsis of paper, it takes time and effort.  You will not be able to start on your paper the night before it is due and expect to do a passing job.  Late papers will not be accepted.  If you have a conflict on the day a paper is due, I expect to receive it EARLY.

 

Participation: Your participation in the class discussions will count for 10 percent of your grade.  If you say something in every discussion class, you'll get the full 10 percent; to encourage uninhibited discussion, I'm not going to grade the content of your comments.

 

I will be happy to discuss your paper and presentations with you and help you put it together in the correct form if you are uncertain what is expected.  However, it is your responsibility to contact the course instructors with your problems.  If I do not hear from you, I will assume that you understand the assignments fully.

 

Office hours: I will not have formal office hours; if you'd like to talk to me, feel free to e-mail me to make an appointment or I'm generally at my office or lab from 8 a.m. to 6 p.m.

 

Academic dishonesty/plagiarism: It is the student’s responsibility to ensure that all work for this class is their own (you may discuss possible paper topics among yourselves).  We will prosecute any and all instances of cheating to the fullest extent allowable by the university.

Copying someone else's writing and pretending that it is yours is a serious violation of the University's Code of Conduct.  If you copy text from a book, article, web page, or other source, or from another student or former student, you will receive a 0 for the assignment. If the copying is particularly extensive or egregious, you will receive a harsher penalty, up to an F for the course.  In some cases, you may also be required to take university mandating courses on appropriate academic conduct to remain a student at UD.

To illustrate the difference between plagiarism and acceptable paraphrasing, here's a passage from Hudson et al. (1987):

The presence of a balanced polymorphism in the coding region of Adh could explain the relatively high level of polymorphism observed in that region. The existence of a balanced polymorphism at a single site can lead to higher levels of neutral polymorphism at linked sites (Strobeck 1983). The reason this can occur is that during the time that the balanced polymorphism is maintained by selection, new mutations will tend to accumulate in the region tightly linked to the selected site.

Copying these words exactly is plagiarism, even if you put "(Hudson et al. 1987)" at the end. It's also plagiarism if you just change a few words, like this:

A balanced polymorphism in the coding region of Adh could explain the high level of polymorphism in that region. The existence of a balanced polymorphism at a single site can cause higher levels of neutral polymorphism at linked sites (Strobeck 1983). This is because during the time that the balanced polymorphism is maintained by selection, new mutations will accumulate in the region tightly linked to the selected site (Hudson et al. 1987).

Instead of copying or trying to rewrite a passage, you should paraphrase it, summarizing the information in your own words:

There is an area around an amino acid polymorphism in Adh that has a relatively high level of silent polymorphism. This may be caused by balancing selection (Hudson et al. 1987).

 

NOTE: All statements of fact must be substantiated by a reference in correct format, preferably from the primary scientific literature.  Failure to reference your sources is also plagiarism. (For instance, this statement on plagiarism is liberally lifted from John McDonald’s course syllabus with permission :).

 

Direct quotes

In papers in other fields, such as English or history, it is common to use direct quotes, putting phrases or sentences from sources in quotation marks. This is because the exact words are important; if you're writing a paper on "Entomological ambiguities in Kafka's Metamorphosis," it's important to quote exactly what Kafka wrote about Gregor Samsa's carapace. As long as you cite the source correctly, using quotes in quotation marks is not plagiarism.

In scientific writing, however, we rarely use direct quotes. Partly, this is just a cultural tradition; partly, it's because when scientists cite another paper, it's because they're writing about the information in the paper, and the exact words used to convey that information are not important. You may use a quotation or two, if you come across a particularly pithy statement of an important concept, but you will get points off for excessive use of direct quotes.

Disabilities: Students suspected of having a learning disability must seek an accommodation from the office of academic enrichment http://www.aec.udel.edu/LD_ADHD_students.html.

 

 

BISC667: "Molecular Mechanisms of Pathogens"

Spring 2008

 

Date               Lecture Topic                                                                     

 

2/11                Introduction/course outline. Bacterial Cell and Genome Structure         

2/13                Molecular Bacterial Genetics I        

 

2/18                Molecular Bacterial Genetics II Horizontal transfer & integrative elements

2/20                Methods in Molecular Pathogenesis I                                            

 

2/25                Methods in Molecular Pathogenesis II       

2/27                Paper Presentations. Articles 1 to 4.                

 

3/3                   Water-borne Diseases I. The Players, Bacteria, viruses, protozoa

3/5                   Water-borne Diseases II. Molecular mechanisms (Vibrio cholerae)

                                                                       

3/10                Water-borne Diseases III. Molecular mechanisms (Salmonella)

3/12                Food-borne Diseases I. The Players, Bacteria, viruses, protozoa                                                        

3/17                Food-borne Diseases II. Molecular mechanisms (Escherichia coli)

3/19                Food-borne Diseases III. Molecular mechanisms (Listeria monocytogenes)

 

3/24                Paper Presentations. Articles 5 to 8.                            

 

************************* End of material for Exam 1*************

 

3/26                            MID-TERM EXAMINATION                                                                      

 

3/29- 4/6   SPRING BREAK

 

4/7                   Airborne Diseases I. The players, Bacteria and viruses                                     

4/9                   Airborne Diseases II: Molecular mechanisms (Legionella pneumophila)

 

4/14                Airborne Diseases III: Molecular mechanisms (Bordetella pertussis)

4/16                Vector-borne Disease I: Bacteria, viruses, protozoa

 

4/21                Vector-borne Disease II. Molecular mechanisms (Borrelia burgdorferi)           

4/23                Vector-borne Disease III. Molecular mechanisms (Yersinia pestis)                   

 

           

4/28                Paper Presentations. Articles 8 to 12.

4/30                Sexually transmitted diseases I: The players, Bacteria and viruses                                          

5/5                   Sexually transmitted diseases II. Molecular mechanisms (Chlamydia trachomatis)    

5/7                   Sexually transmitted diseases III.  Molecular mechanisms (HIV)

                       

5/12                Emerging Infectious Diseases (Staphylococcus aureus)            

5/14                Origins of major human infectious diseases                                 

 

5/19                Paper Presentations. Articles 12 to 16.

 

************************* End of material for Exam 2*************

 

5/21                            FINAL EXAM

 

 

Research Papers: The following are a list of research papers that students are expected to read (articles 1 to 18) and present (articles 1 to 12) to supplement their notes from class.

 

1.      Hacker J and Carniel E.  Ecological fitness, genomic islands and bacterial pathogenicity. A Darwinian view of the evolution of microbes.  EMBO Rep. 2001 May;2(5):376-81.

2.      Wagner PL, Waldor MK. 2002.  Bacteriophage control of bacterial virulence.

      Infect Immun. 2002 Aug;70(8):3985-93.

3.      Faruque SM and Mekalanos JJ.  Pathogenicity islands and phages in Vibrio cholerae evolution.  Trends Microbiol. 2003 Nov;11(11):505-10.

4.      Burrus, Vincent , Joeli Marrero and Matthew K. Waldor. 2006.  The current ICE age: Biology and evolution of SXT-related integrating conjugative elements. Plasmid 55:173-183.

 

5.      Heithoff DM, Conner CP, Hanna PC, Julio SM, Hentschel U, Mahan MJ. Bacterial infection as assessed by in vivo gene expression. Proc Natl Acad Sci U S A. 1997  4;94(3):934-9.

6.      Saenz HL, Dehio C.  Signature-tagged mutagenesis: technical advances in a negative selection method for virulence gene identification.  Curr Opin Microbiol. 2005 Oct;8(5):612-9. Review.

7.      Merrell DS, Camilli A. Acid tolerance of gastrointestinal pathogens.Curr Opin Microbiol. 2002 Feb;5(1):51-5.

8.      Nielsen, Alex Toftgaard , Nadia A Dolganov, Glen Otto, Michael C Miller, Cheng Yen Wu, and Gary K Schoolnik.  2007.  RpoS Controls the Vibrio cholerae Mucosal Escape Response. PLoS Pathogen. 2(10): e109.

 

 

9.      Elahi, Shokrollah , James Holmstrom and Volker Gerdts. 2007.  The benefits of using diverse animal models for studying pertussis. Trends in Microbiology, 15(10):462-8.

10. De Buck, Emmy , Jozef Anné and Elke Lammertyn.  2007.  The role of protein secretion systems in the virulence of the intracellular pathogen Legionella pneumophila. Microbiology, 153(Pt 12):3948-53.

11. Hovius JW, van Dam AP, Fikrig E.   2007.  Tick-host-pathogen interactions in Lyme borreliosis.  Trends Parasitol.23(9):434-8.

12. Riedel CU, Monk IR, Casey PG, Morrissey D, O'Sullivan GC, Tangney M, Hill C, Gahan CG.  2007.  Improved luciferase tagging system for Listeria monocytogenes allows real-time monitoring in vivo and in vitro. Appl Environ Microbiol73(9):3091-4

 

13. Ohnishi M, Tanaka C, Kuhara S, Ishii K, Hattori M, Kurokawa K, Yasunaga T, Makino K, Shinagawa H, Murata T, Nakayama K, Terawaki Y, Hayashi T. Chromosome of the enterohemorrhagic Escherichia coli O157:H7; comparative analysis with K-12 MG1655 revealed the acquisition of a large amount of foreign DNAs.DNA Res. 1999 Dec 31;6(6):361-8.

14. Baker S, Dougan G.  The genome of Salmonella enterica serovar Typhi.Clin Infect Dis. 2007 Jul 15;45 Suppl 1:S29-33.

15. Sirand-Pugnet P, Lartigue C, Marenda M, Jacob D, Barre A, Barbe V, Schenowitz C, Mangenot S, Couloux A, Segurens B, de Daruvar A, Blanchard A, Citti C.  Being pathogenic, plastic, and sexual while living with a nearly minimal bacterial genome.  PLoS Genet. 2007 3(5):e75.

16. Terekhova D, Iyer R, Wormser GP, Schwartz I.  Comparative genome hybridization reveals substantial variation among clinical isolates of Borrelia burgdorferi sensu stricto with different pathogenic properties.  J Bacteriol. 2006 Sep;188(17):6124-34.

 

17. Bryant JE, Holmes EC, Barrett AD.Out of Africa: a molecular perspective on the introduction of yellow fever virus into the Americas.  PLoS Pathog. 2007 May 18;3(5):e75.

18. Wolfe ND, Dunavan CP, Diamond J.  Origins of major human infectious diseases.  Nature. 2007 447(7142):279-83.

 

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