Course Information



SUBJECT MATTER: Developmental programs of microorganisms are initiated and maintained in response to the organisms' critical evaluation of its environment. The presence or absence of nutrients, noxious substances, and other environmental factors as well as the number of individuals (cells) in the immediate vicinity all must be continually monitored and interpreted. Based on this information, a decision must be made as to what course of action is best for the cell--continued growth but at altered rate, enter stationary phase, undergo a developmental program. Many inputs have to be integrated and weighed appropriately for the correct decision to be made and implemented as often a significant percentage of the cells will not survive at the end of the developmental program.

Many insights have been obtained in recent years on the molecular mechanisms which underlie the regulation of developmental programs in microorganisms and on the sensing, integration, and decision making steps. A number of common themes as well as species-specific solutions have been identified.

The rationale or motivation behind developmental programs in microorganisms is very different from that for typically thought of developmental programs--gamete fusion and embryogenesis. The goal of latter program is to generate a new individual. For microorganisms, the programs are to ensure that some individuals survive when the immediate environment does not favor propagation and growth of the individual.

COURSE GOALS: The aim of this course is two fold: first to examine the molecular details of the control of development in microorganisms. A large part of this will be trying to understand the complex interplay between the cells and the environment and between one cell and another. The sensing and signaling mechanisms will be discussed along with how these are integrated to come to a consensus determination of the appropriate path for the cells to take. An examination will be made of the mechanisms used to continuously monitor the environment once a developmental program is underway and the feedback mechanisms which allow progress or abortion of the program.

The second goal is to become comfortable with reading, discussing, and presenting the scientific literature. In fact, much of your grade will be determined by your progress towards this goal, independently of what you may learn about microbial development.

CLASS FORMAT: Almost all of the class will be in a presentation/discussion format that will center on commonly or individually read papers. Much of the discussions will be student-led. Participation in class will be a large determinant of the final grade (70%). There are two parts to your participation. The first is when you are the lead presenter, either in a group of three students or individually. You will be judged on how well you do the following things:

1) give a clear but brief statement of what the work in the paper was addressing
2) present a concise overview of what led to the work, why it was undertaken, and why it was important to do so
3) indicate how the problem was addressed--the general approaches and methods used
4) describe what the major findings were, i.e., the results
5) indicate what conclusions can be drawn based on the results
6) identify any potential problems with the conclusions, any alternative explanations the authors did not present, etc.
7) integrate the findings/conclusions with what we have discussed previously

In all of these, please try to include critical assessment of the work and your own input into interpretations, problems, etc.

The second part of your participation is when you are not the lead presenter. You will be expected to read all the papers that we discuss, and you will be expected to contribute to the discussion on each paper. If you are shy, you better get over it soon. Nothing you say will be held against you--in other words, your comments and questions are welcomed independently of whether we eventually determine you were correct in what you said. I want to see evidence that you are thinking (hopefully in a critical manner) and am less interested in if you know all the "right' things.

A PAPER: The remaining 30% of your grade will be a paper due at the end of the semester. The paper should be no more than 5-7 pages (in other words, it should be concise), double spaced and typed. It should be a critical review of a specific, outstanding problem in microbial development and will involve the use of at least 3 to 5 related papers addressing the problem. Grading will reflect the degree of critical evaluation of the material and the amount of independent thought woven into the paper. The topic of your paper can be one of your own choosing (but it must be OK'ed by me) or I will have several topics from which you can choose.