Jerry R. Mohrigl and Nancy M. TooneyZ H o ~ eCotleae ~ o a n d~ , i h i n
II
Biochemistry in the Undergraduate Curriculum A n interdisciplinary course
T h e increase in interest in biochemistry in the undergraduate curriculum mirrors the exponential growth of the field of biochemistry itself. The ACa report of the Conference on Biochemistry and Chemistry ( I ) noted that approximately 300 doctorates are awarded annually in the field of biochemistry. This number represents about 20% of the number of doctorates granted in chemistry per year, and the percentage is growing steadily. The excitement generated by DNA, cancer, protein biosynthesis, and hormone research has already touched the high school student. Yet the integration of biochemistry or biochemically oriented topics into the undergraduate chemistry curriculum tends to be rather haphazard. I n the four-year undergraduate college the situation is particularly acute. Since there is no graduate level course in biochemistry which can be opened to senior level students, either a separate course must be designed or biochemistry must be integrated with other course material, such as organic chemistry, physical chemistry, or molecular biology. Depending upon the interests and training of the staff, the structure of a biochemistry course a t the undergraduate level has ranged from a course oriented towards natural products taught in a chemistry departmcnt to a course centered around cell physiology taught in a biology department. There are several effective ways in which biochemistry may be presented in the chemistry curriculum. The "Biorganalytical" course offered a t the University of California a t Los Angeles (8) demonstrates an interesting synthesis of the three disciplines a t the sophomore level. Alternatively, biochemical topics have been introduced into the freshman program a t a number of colleges and universities. The program a t Yale University has recently becn described in THIS JOURNAL (3). A one-semester senior course in biochemistry is now a common offering in many colleges. In the past, a t Hope College, a semester lecture course in biochemistry has been offered to junior-senior students. The Kettering Foundation Internship Program operating through the Great Lakes Colleges Association offered us an opportunity to design a new biochemistry course involving a team teaching approach. Through this program a biochemist with a joint appointment in the biology and chemistry departments worked with an
' Present Addresi;: Department of Chemistry, Carleton College, Northfield, Minnesota 55057. a Ketterirrg Foundation Teaching Intern, Hope College, 196667. Present address: Children's Cancer Research Foundation, Inc., 35 Binney Street., Boston, Massachusetts 02115
organic chemist having an active interest in biochemistry. Our purpose was to design a course in which the concepts of contemporary biochemistry and molecular biology could be presented in an integrated form to a group of junior-senior level students with diverse iuterests and backgrounds. A year course involving a laboratory was offered for credit both in the biology and in the chemistry departments. Organic chemistry was a prerequisite for the course. About half of the students who enrolled had takcn or were simultaneously taking quantitative analysis. In general, most of the chemistry majors had not had any biology courses. Several chemistry majors had previously taken or were taking concurrently a year course in physical chemistry. Among the 32 students enrolled for the first semester, five were biology majors, 13 premedical or predental students, and 14 were chemistry majors. About 25 of these students are entering or planning to enter graduate school or medical/dental school. Four students have entered IJhD programs in biochemistry. The textbooks used for the coursc were Peter Karlson's "Introduction to AIodern Biochemistry" (4) and James D. Watson's "l\/lolecular Biology of the Gene" (5). Several outside readings were required. These were frequently taken from the ScientiJc Amelican. Problem sets were assigned intermittently, depending on the nature of the subject material. For example, a review of acid and base phenomena and buffer calculations were included in two problem sets and discussed in extra sessions with those students needing additional help. Many problems were taken from the literature or from Dawes' "Quantative Problems in Biochemistry" (6). During the second semester, students were required to write a critique of a paper selected from the current biochemistry literature. The first semester course had three lecture hours per week and carried three hours of credit. I n the second semester, students had the option of taking only the lecture course with two weekly lectures, for two hours of credit, or also participating in laboratory work for one additional credit hour. Although i t is our feeling that all students should do laboratory work, our facilities did not permit us to handle more than a dozen students in the laboratory. Among these twelve students were seven chemistry majors, three biology majors, and two premedical students. Since we were not certain how many students would be able to fit a year sequence into their course of studies, we attempted to structure the topics during the first semester as a reasonably complete Volume
46, Number I, lonuory 1969 / 33
Table 1.
Lecture Outline
Table 2.
Percent of Course Time Devoted to Topics
First Semes1er
I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 hours Biochemical methods An overview of oellulsr chemistry 11. CellTopoloav . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3. Cell structure and funotion Ilioohemioai compartmentation Intmduotioo t o moieeular genetic* 111. Proteins Chem/stry of t h s amino acids.. . . . . . . . . . . . . . . . . . . . . . . 1 Yeptldes 1 The yeptide bond Peptide synthesis Naturally occurring peptides Protein struoture and function. . . . . . . . . . . . . . . . . . . . . . . . . 6 Primary, secondary, tertiary, quaternary structures Techniques of protein analyais IIvdroee" bondin= and "hvdroohnhic" forcap . ~. Dhmthration The three dimensional structure of myogiobin IV. Nuoleio Acids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Purines, pyrimidines, nuoleosides, nueleotides P n m a w and seoondary struoture of DNA and RNA's nu ole^ aord biosyntheais Introduction t o protein synthesis and t h e genetic code V. Bioohemioal Catalysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Enryme structure and function Enzymesubstrate intersotions Enzyme kineties Detailed mee1,anistio studies on chymotrypsin and iranrddnlase Meehmisms of eoenayme aotivity Pyridoxnl phosphate Thiamine p y r o ~ h o s p h a t e VI. Carbohydrate utiliaation ............................. 6 Carbohydrates and powsaccharides Embdon-Meyerho1 pathway and enzymes T h e pyridine nuo!eotides Olyrogen synthesm VII. Bioenergetics l'roduotmn h d transfer of chemical energy.. . . . . . . . . . . 4.5 Revierr of e~uilibriumthermodynamios Energy Rich;' compound-ATP, Aoetyl CoA
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~
~~~~~~
~~~~
~~
8.0 10.2 5.7 6.1 10.0 9.1 4.7 5.1 3.0 8.0 6.8
... ... ... ... ...
2.7
~~~
~
C"il"l~rl .........rcart,nna .........
Group transfer reactions Biooridations . . . . . . . . . . . . . . . . . . . . . . . The I
