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Wendy Jastremski '95 Finds Her Niche in the Chemistry Department

By Cristy Nguyen                         October 22, 1993

It was Wendy Jastremski's experiences in her introductory chemistry classes that fostered her interest in organic chemistry. Combining chemistry with her interests in environmental studies, Wendy is well on her way to an exciting interdisciplinary career.

Not unlike most first-year students, Wendy Jastremski '95 didn't know what she wanted to major in when she first arrived on campus in the fall of 1991. She did know, however, that she was interested in the environment, especially waste management, and began to look for a curriculum that would complement these interests. Deciding that she would like to attack the environmental problem from a science-related angle, rather than from the administrative side, Wendy joined 300 or so other students in Chemistry 5 during her first winter term. This experience she labels as "miserable, because at first the class was so large and impersonal, the material was difficult and the concepts were too broad. It was very hard for me to get into the material we were studying." But what she also found from this experience was a group of professors who were extremely accessible, helpful and sincerely interested in her progress.

Wendy says that she would attend her Chem. 5 professor's office hours at least once a week and always stay for an hour or so, often discussing more than just the class material. She says, "We would talk about anything, he would ask me how my other

"We would talk about anything, he would ask me how my other classes were going, and stuff like that. It was actually my Chem. 5 professor who gave me some great ideas for a paper assigned in another class!"

 classes were going, and stuff like that. It was actually my Chem. 5 professor who gave me some great ideas for a paper assigned in another class!" Encouraged by the support she found in Chemistry 5 and 6, Wendy continued on to take Chemistry 51, the dreaded "orgo" class. Despite rampant rumors of the horrors of organic chemistry, she found the material manageable, even interesting, and soon it had become her favorite class. Once again, she found the chemistry professors to be "amazing teachers, and very helpful." When she became a teaching assistant
for Chem. 51 this fall, she says her old professor greeted her with an enthusiastic "Welcome aboard!" "It felt good," she says. Extolling the virtues of the Organic Chemistry class, as well as the entire Chemistry Department, Wendy cited them as major factors in her decision to become a chemistry major.

In order to incorporate her environmental concerns into her field of study, Wendy also elected to work towards an Environmental Studies certification. She has also found this to be a worthwhile experience, saying she has learned more than science from classes such as Earth as an Ecosystem (ENVS 2), Global Environmental Science (ENVS 30), and Environmental Law (ENVS 60). She also found the Environmental Chemistry class (Chem. 63) to be interesting, and says that she has been able to take courses in both departments which complement each other, as well as her present career goals. During the summer after her first year at Dartmouth, Wendy worked at the Stonington town dump, where she helped them implement their first recycling efforts. She says she worked right at the dump, educating and encouraging citizens about recycling, and remembers it as a great experience. At Dartmouth, Wendy was involved in the Dartmouth Outing Club's Environmental Studies Division (DOC/ESD), which works on campus to promote awareness of environmental issues. Wendy was also an English 2 tutor, an undergraduate advisor, and a member of the Dartmouth Women's Rugby Club.

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Biogeo-What? Biogeochemistry!

By Liz Maier '97                         July 13, 1997

Biogeochemist Andy Friedland describes his field, how he got there, and where it might lead you!

I had a chance to ask Professor Friedland a few questions about what it means to study biogeochemistry, an interdisciplinary field that draws upon almost every basic science out there. Have you ever studied the nitrogen cycle? The increase in global atmospheric CO2? Acid rain? Then you have been exposed to biogeochemistry! Professor Friedland teaches a number of Environmental Studies classes, including: ENVS 1, Humans and Nature in America; ENVS 2, Earth as an Ecosystem; ENVS 79, Soil Science; and ENVS 89, Forest Biogeochemistry. If this interview piques your interest, be sure to investigate the new biogeochemistry web site at: http://www.dartmouth.edu/artsci/envs/courses/envs89.html, for more information about red spruce decline and other biogeochemical issues.

Q: How did you get interested in science?
A: I don't know exactly, but I know I became interested in the environment in fifth grade, and I know that it was environmental science that I became most interested in. And that's because my fifth grade class, as part of the first Earth Day in 1970, went to what was then called a swamp -- Red Maple Swamp, near my elementary school. We cleaned up the litter and trash, and made some trails.,..and learned some of the species and things like that. So when people say, " Oh, I'm going to be an elementary school teacher," and some people treat that with disrespect, I think you have a great opportunity to influence a lot of people that way, and I think that's what got me interested in science.

 So when people say, "Oh, I'm going to be an elementary school teacher," and some people treat that with disrespect, I think you have a great opportunity to influence a lot of people that way, and I think that's what got me interested in science.

Q: What did you study in college?
A: I did a double major in ecology and environmental studies. I was pretty sure by the time I was in college that I wanted to focus on environment, but since my most exciting teacher in high school had been a history and constitutional law teacher, I came in thinking I wanted to do political science and international relations. And then I envisioned that I would use that to become some sort of environmental lawyer or environmental governmental official. But -- this was at the University of Pennsylvania -- in this course in international relations my freshman year, you'd have to wait in line for an hour to see the T.A....not the professor, the T.A.! And I very quickly moved away from international relations and found the environmental studies department, which was really the same thing as the geology department, which was my undergraduate home. And then I ended up staying at Penn and doing a Ph.D. in geology.

Q: What convinced you to go to graduate school?
A: It's not something that I planned. Lots of times I talk to undergraduates who want to lay out their whole [career], and I always refer to that as trying to line your ducks up in a row. Sometimes that's doable, and I try to do that, but other times you just sort of see what
In no way was there a master plan. I just took good opportunities.

opportunities there are. I got the opportunity to work with a professor of geology and environmental studies, and we did some field work, and that just rolled into some other

work, and they said, "Why don't you consider doing a Ph.D. here?" In no way was there a master plan. I just took good opportunities.

Q: When did you decide to become a professor?
A: The thought was to get a Ph.D., but I thought I might do environmental consulting or work for the government, work for the EPA....I guess by the time I was at the end of my Ph.D., I thought that it would be a great opportunity to be able to do research and teach.

Q: What did you do your graduate work in?
A: My graduate work was in trace metal biogeochemistry in forested ecosystems.

Q:What is biogeochemistry?
A: Biogeochemistry is the study of interactions between the atmosphere, the terrestrial biosphere, and the underlying soil and bedrock.

Q: What projects did you work on when you first came to Dartmouth?
A: I came to Dartmouth and had been involved with looking at red spruce decline, which we eventually showed was connected to air pollution, although not exclusively air pollution. I came in the fall of '87, and by the summer of '88 I had a couple of Dartmouth undergraduates and a bachelors student from the University of Pennsylvania (who couldn't get an advisor at Penn, so called me up and asked if I'd be his advisor for his bachelors thesis at Penn), and a couple other people, and we went running around the mountains of New England and New York making measurements relating to red spruce decline. And in that study, which was the only one that really looked at a west-east gradient, meaning that air pollution decreases as you go from west to east, we looked to see whether red spruce decline decreased as you go west to east, and in fact it did. It did not prove that air pollution caused the decline, or the lack of decline to the east, but nevertheless it was an interesting correlation. That was pretty prominently cited in a few locations in the National Atmospheric Precipitation Assessment Program reports about acid rain. So that was something I did just very quickly on coming.

Another thing I got started on [I] worked on very closely with an undergraduate...named Graham Herrick, who ended up doing a lot of good work with me. I was here now all of a
sudden really close to mountains, and working in the winter was an option, whereas when I was in Philadelphia, it was kind of a hassle. I would often try trips in the winter, but storms would either prevent me from getting up to Camel's Hump or from getting back after a trip.

 I was here now all of a sudden really close to mountains, and working in the winter was an option...
Whereas here, I could, depending on the day, go or not go, depending on the weather. It was much easier, because it was all within an hour's drive. So Graham and I designed a couple of projects, one of which he did most of while I was in Kenya, where we looked at water relations in needles on Mount Moosilauke. So that was perhaps the second project I started after coming to Dartmouth.

And for Graham and eventually for me, too, and others who worked with us, one of the most exciting things was that we'd pack these red, plastic sleds that kids use on the golf course. We'd strap them to the pack -- they'd weigh almost nothing -- on the way up, and on the way down, you'd have this thirty minute bobsled run! Of course, we were doing it for the science, right? But it sure was fun. And that helped us get volunteers to come and help us with our work.

Q: What projects are you working on now?
A: One of the major projects I have going on right now is a long-term study of the biogeochemistry of major elements at Whiteface Mountain. This is a collaboration with Eric Miller, who is a research assistant professor in environmental studies. It's a study of the deposition of a variety of elements, particularly nitrogen, calcium, magnesium, and potassium.

If you had to describe my work, I am interested in how human beings have altered or perturbed elemental cycling patterns and rates, and elemental distribution in temperate forests. And I have two focuses: one is a particular system, a spruce-fir-birch system of high elevation mountains in New England and the high Adirondacks in New York; and with respect to elements that I study, there's a group of major elements -- calcium, magnesium, potassium, nitrogen, sulfur -- and trace metals -- lead, copper, zinc, nickel, and cadmium -- with probably the greatest focus on lead.

Nitrogen is presumably an element that did not cycle as much -- there wasn't as much deposited, there wasn't as much cycling -- prior to human activity. Lead was another element, and so for a long time my two contrasting elements were nitrogen and lead. Nitrogen was something plants need in large amounts and we are supplying in large amounts by the combustion of fossil fuels. On the other hand, lead is something we've provided lots of through the use of leaded gasoline, but it's something plants and ecosystems need none of. So that's an interesting comparison to make.

Q: What is the best preparation for students who are excited by your field?
A: I think biogeochemistry has a foundation in ecosystem studies, which is a part of ecology. So I'd say if someone thinks that biogeochemistry is interesting, it's important to know your chemistry and your geochemistry, but the intellectual foundation is in ecology. So
So I'd say if someone thinks that biogeochemistry is interesting, it's important to know your chemistry and your geochemistry, but the intellectual foundation is in ecology.

I'd encourage people to consider taking ecology courses. And another thing would be to consider some of the courses that are available in Earth Sciences. There's Geochemistry and Environmental Geology -- those are two courses that are relevant. And within Environmental Studies, ENVS 30, Global Environmental Science, and then there's Forest Biogeochemistry, of course. So for example, taking a course in oceanography and marine ecology might be relevant, because in some ways the oceans are the

ultimate repository for most of terrestrial biogeochemical cycling. It's really a broad field, and depending on where you get interested, you could find something of interest in almost all of the science departments on campus.

Q: What are the job options for biogeochemists?
A: Among undergraduates who have had a focus on biogeochemistry -- I'm thinking of people who have taken, say, both Soil Science and Forest Biogeochemistry, and other courses in earth sciences and ecology -- I've observed people go on and work in consulting firms in Washington D.C. and Boston and elsewhere, where they are doing various aspects of scientific consulting, whether it's some aspect of the Superfund legislation, or other toxic or hazardous waste-related enforcement or analyses. I've seen people go and do things in the solid waste and recycling fields; I've seen people go and get jobs from other faculty members as technicians -- field technicians, laboratory technicians. People have worked in various environmental institutes of one sort or another, or have gone to work for the EPA or a state environmental protection organization.

Q: So there are plenty of opportunities available in this field without a higher degree?
A: It appears that there are opportunities, although my impression is, speaking to...some people I got to know best, like my Kenya students, people who have been out five and seven years, in the last year or two a great number of them have been going back to graduate school. So it seems like you can go out [into the job market], but that within five years or so, people seem to want to do something more. So they are applying and going to places like Yale School of Forestry and Environmental Studies, Duke School of the Environment, law school, and business school.

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Karen Miller, Chemist Extraordinaire

By Kathryn Greer '00                         February 21, 2000

Karen Miller '00 is one who always seems to know what's going on, especially in chemistry classes. Having worked on a group lab project with her, I can say that this woman truly does know her chemistry. She not only knows her chemistry for classes, but has also done much chemistry work outside the classroom.

Karen came to Dartmouth with the intention of majoring in chemistry, but thought her chemistry career would end at that. She knew she had an interest in chemistry, and chose Dartmouth in part because of the chemistry department's excellent reputation.
Little did Karen know she would come to love organic chemistry. She took the introductory chemistry classes, general and organic chemistry, and definitely enjoyed Little did Karen know she would come to love organic chemistry.
them, but it was not until she took Chemistry 59 (Special Topics in Chemistry), that she found her true passion. In the class, students spent the last four weeks of the term working on an independent project - not the traditional labs that most introductory classes have, but an actual research project. Karen worked with Heidi Hassinger, a graduate student who has since received her doctorate degree. Karen's role was to complete a six-step synthesis, creating a precursor to the molecule Hassinger was studying for her post-graduate work. She used many different techniques for the synthesis, a terrific learning experience.

During her sophomore summer, Karen worked as a lab assistant to Professor Gordon Gribble in the chemistry department. Professor Gribble's specialty lay in organic chemistry, so Karen was able to learn yet more about this branch of chemistry that continued to fascinate her. Because she had enjoyed her chemistry classes so much, she had applied for a Presidential Scholar program in organic chemistry with Professor David Lemal her sophomore spring. She switched to working in Professor Lemal's laboratory and has been working there since her junior fall. The Presidential Scholar program is a two-term commitment, and if a student completes just the two terms, he or she is called a Research Assistant. If the student's research culminates in a thesis, as Karen plans to do, the student is considered a Presidential Scholar.

Karen worked in Professor Lemal's lab as a Presidential Scholar for her junior fall, and then decided to work on-campus full-time that spring as she was not taking classes. Karen worked in Professor Lemal's laboratory with the aid of a Howard Hughes Biomedical Science Grant, which allowed her to live in Hanover and work full-time in the lab. Though the Howard Hughes grant is no longer available to students, she noted that students interested in going into the sciences as a career can apply for several research grants available to students on campus, such as the Richter Honor Thesis Grant. Karen advises students speak with Sandy Gregg, who works to coordinate grants for students.

Karen enjoys the independence her lab work affords her, the fact that she can work on it at any time and the problem solving aspects of her work.

Karen is currently working on her Presidential Scholar thesis in organic chemistry, attempting to create di-fluoro-cyclobutadiene. Karen enjoys the independence her lab work affords her, the fact that she can work on it at any time and the problem solving aspects of her work. She also likes the freedom to think independently in her work.

While Karen truly enjoys her work, she does find it frustrating at times, especially in regard to time. "It's difficult to schedule lab work because if you're in a situation where you have a three-hour block of time and something takes you two and a half hours when you thought it would take you a half hour, it can get very frustrating." Karen also has many other activities that she must balance with her intense lab work. She is an active member of Chamber Singers, and wrote "Bard by a Crystal Fountain," a musical mixture of skits and songs performed by the Chamber Singers this winter. Karen also has a part-time job and is a member of the Casque and Gauntlet senior society. While she finds it difficult at times to balance all of these activities with her hours in the lab, she certainly has success at it and finds it very rewarding.

Karen is currently hearing from and deciding on graduate schools in chemistry for next year. She plans to spend about five years getting a Ph.D. in organic synthesis and eventually work in industry rather than academia. Karen worked for Wyeth-Ayerst Pharmaceuticals this past summer and was impressed by the environment she found in industry work. Karen commented, "I'm just amazed with the resources that they have in industry, and you can do...any chemistry you would want...It is limiting in a sense because it has to be something that's...applicable to pharmaceuticals." However, the pharmaceutical industry is vast and Karen is very excited about the prospect of working in industry in the future.

Karen's advice to other students interested in doing lab work as an undergraduate is to
Karen's advice to other students interested in doing lab work as an undergraduate is to get involved early and to try working in a few different labs.

get involved early and to try working in a few different labs. She enjoyed being able to see first-hand some of the different kinds of research performed by the Professors at Dartmouth and also in other labs on off-campus terms. Karen was able to work in the chemistry department as early as her sophomore year. She also recommends that students try to find a way to work in a lab full-time.

Many opportunities exist for students to study and work in many fields of science. Professors are great resources for finding a research job, as are upperclassmen students who may know of positions and openings. If you wish to work in a lab, take a bit of effort and you can do just that.

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Looking at Biology Through a Chemist's Eye

By Chris Wilson                         October 29, 2001

What does a molecule look like? Why do we need to know? How do computers factor in?

Dr. Amy Anderson in the Chemistry Department in Burke is answering those questions and more (http://www.csbcc.dartmouth.edu/acalab.html). I met with one of her graduate students, Brian Stevens, in the lab one sunny morning. The lab is new, the equipment is new, and some of it is still being unpacked and assembled. Dr. Anderson has only been at Dartmouth for two years, but she already has four graduate students and three undergraduates working for her. Brian showed me around and helped decipher some of what's going on in the lab.

"The structure of a molecule can tell you many things," Brian said. By studying the structure of an enzyme that is essential to the life of a pathogen, antibiotics can be designed to inhibit that enzyme, thereby killing the pathogen. By studying the structure of a molecule of an organism that has become drug resistant, it is possible to visualize how it became resistant, and redesign antibiotics accordingly.

 Dr. Anderson has only been at Dartmouth for two years, but she already has four graduate students and three undergraduates working for her.

The Steps Involved

The first step is to extract the enzyme. An enzyme is a protein inside living cells that has a particular function, like enabling DNA replication to occur. To get to the enzyme, grow bacteria that contains the enzyme, place the bacteria in a centrifuge to break the cells

Image Credit: Cody, V., Galitsky, N., Rak, D., Luft, J. R., Pangborn, W., Queener, S. F.: Ligand-Induced Conformational Changes in the Crystal Structures of Pneumocystis Carinii Dihydrofolate Reductase Complexes with Folate and Nadp+ Biochemistry 38 pp. 4303 (1999)

apart to free up the intracellular material, and freeze the samples immediately. The samples must be kept frozen to keep proteins from 'unfolding'. The frozen samples are brought into the cold room, which is kept at 4 degrees C, where the specific proteins are collected using column chromatography techniques. This process takes a few days.

Then the sample is crystallized. This is the step Brian is currently struggling with. Proteins do not form crystals easily, unlike salts and sugars. Brian explained the crystallization process as similar to placing a drop of salt water on a bench and waiting for the water to evaporate, leaving just the salt crystals. Depending on the protein involved, this process can take many trials, and perhaps even months to complete.

Once the protein is crystallized, the sample is placed in a machine that bombards it with an X-ray beam and collects the 'diffraction data', meaning the ways in which the beam reflects off the sample. The

diffraction data looks like a bunch of dots. "Think of diffraction data as an unfocused image in a microscope," said Brian. Using high-powered mathematics and high-powered computers, scientists are able to "focus the picture", adding color to create a visual work of art.

Scientists worldwide are solving molecular structures and making their discoveries available to each other via the web. The structure pictured is from the protein database webpage (www.rcsb.org) where all solved structures eventually get posted and made accessible to the scientific community. The structure is DHFR (an enzyme involved with DNA replication) from the organism Pneumocystis carinii, with two molecules attached, folate and NADP+ (shown in ball and stick).


Scientific Worlds Collide--With Amazing Results

One of the most fascinating things about this research is how interdisciplinary it is, presumably out of necessity. The techniques come from chemistry, biochemistry, molecular biology, structural biology, and biophysics. Intense computing is used to collect data, analyze data, and derive three-dimensional structures. A working knowledge of

 One of the most fascinating things about this research is how interdisciplinary it is, presumably out of necessity.
math and physics is necessary to understand and use the x-ray techniques. These scientists are operating in that realm just on the edge of chemistry and biology, where computers meet to give them a bird's eye view into the smallest of worlds. Brian, as an undergraduate, was a double major in biology and chemistry, and he feels like he constantly draws on his core knowledge from both of those sources. And now, as a graduate student, he is "looking at biological molecules as a chemist." With a little bit of computers thrown in.

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