Using a Poetry Reading on Hemoglobin To Enhance Subject Matter

Nov 29, 2012 - A reading of the poem “Jerry-Built Forever” (on various aspects of hemoglobin) is used as an ... Garland L. CrawfordKathryn D. Kloe...
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Using a Poetry Reading on Hemoglobin To Enhance Subject Matter Richard S. Herrick*,† and Robert K. Cording‡ †

Department of Chemistry, College of the Holy Cross, Worcester, Massachusetts 01610, United States Department of English, College of the Holy Cross, Worcester, Massachusetts 01610, United States



ABSTRACT: Poetry reading is identified as a fun way to review chemistry topics and spark student interest in the beauty and mystery of chemistry. A reading of the poem “Jerry-Built Forever” (on various aspects of hemoglobin) is used as an example; the poem is included in the article. Details of how the reading was performed and reactions of the students are presented.

KEYWORDS: General Public, Inorganic Chemistry, Biochemistry, Analogies/Transfer, Communication/Writing, Proteins/Peptides



INTRODUCTION Chemistry is a mysterious and beautiful science. We often lament that our students do not appreciate this statement. We know that they must wrestle with concepts, learn facts, and perform effective hands-on laboratory work over an extended period of time before reaching a true understanding of the subject. Learning chemistry is hard work. However, the way we teach and communicate (or do not communicate) the subject to our audiences is one cause of this problem. Because of its technical complexity, we necessarily spend most, or even all, of our educational efforts ensuring that our students can navigate the trees―the objective, fact-laden, concept-rich heart of the subject. Yet we often neglect to focus on the forest, the more subjective arena where the intrinsic allure of chemistry and its connection to people is manifested. Another reason that people do not appreciate the mystery and beauty of chemistry relates to human nature. John Donne, in his poem “Of the Progress of the Soul: The Second Anniversary” (1612), wrote, Why grasse is greene, or why our blood is red, Are mysteries which none have reach’d unto. These were indeed mysteries when this poem was written 400 years ago. But intense efforts by countless dedicated men and women have led to a detailed understanding of what makes grass green and blood red and a comprehensive understanding of chlorophyll and photosynthesis, of heme porphyrins and hemoglobin. We know why blood is red, and so much more. For example, we know that hemoglobin has four heme units embedded in four globular proteins; that the individual heme units bind oxygen and that they bind oxygen more tightly in an oxygen-rich environment; that fetuses use fetal hemoglobin to compete with their mother’s hemoglobin for the oxygen they need; and that the fetal hemoglobin is replaced with the adult © 2012 American Chemical Society and Division of Chemical Education, Inc.

form shortly after birth. Entire books are devoted to hemoglobin. However, by constructing this arsenal of knowledge, poetic mysteries can become dull facts. One can imagine a student asking about the color of blood and getting the response, “The cause of the red color in blood is due to the Soret band, an intense peak in the blue wavelength region of the visible spectrum that is characteristic of heme proteins.” The answer is perfectly accurate, but where is the mystery? Where is the beauty? While it takes time away from learning the concepts and facts of chemistry, occasionally taking the time to focus on its underlying allure can enhance student understanding and appreciation. There are many ways to accomplish this. There are books for a general audience that deal with these aspects of chemistry. Two important nonfiction examples are Primo Levi’s book, The Periodic Table,1 and Oliver Sacks’s book, Uncle Tungsten.2 Each is partly autobiographical. Levi’s book is deeply moving, dwelling partly on his imprisonment by the Nazis and partly on his career as a chemist. He uses a chemical element as the title of each chapter and as a metaphor for the subject of that chapter. Sacks recounts his fascination with chemicals and the periodic table in his humorous remembrance of his early life. Both books received high praise from the scientific community and the wider literary community; Levi’s book was named “the best science book ever” in 2006 by the Royal Institution.3 There are also works of fiction,4,5 plays,6,7 or paintings8 that combine chemistry and the arts in ways that can bring out the beauty and mystery of chemistry. Similarly, there have been reports of using the arts in the classroom as a way to teach or reinforce the learning of chemistry. Teachers have sung popular Published: November 29, 2012 215

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DISCUSSION POINTS The discussion began with a brief explanation by R.S.H. of some of the key points that Roald Hoffmann is making in the poem. These are listed below. The poem is “chunk-to-knowledge-chunk” with five different levels of comments. First, it was noted that there are several general science references early in the first section; “[F]ar bangs and dodges of light in space” infers the Big Bang, supernovas, and the observation of gravitational lensing that provided early proof of Einstein’s theory of general relativity. Other general science references mention the shallow Azov Sea and the distinctive peeling of bark from a birch tree. There are also chemical themes, including mention of the defensive spray of the bombardier beetle, frequently discussed in organic chemistry and biology courses because of the distinctive, hot, caustic mixture of hydrogen peroxide, quinones, and hydroquinones that the beetle produces. Second, there are many references, more beautiful than you would find in a textbook, describing the structure of hemoglobin. For example,18 Beauty whirls rococo In fussy chains round The oxygen pocket; beauty Cambers simplethe iron Hub of heme. The references to the allosteric nature of hemoglobin neatly illustrating the great structural changes because of the cooperativity effect are presented most elegantly:18 Oxygen, Enflamer, winds to a pocket Molded by protein, binds iron, moves It in consummation, chains Tethering heme tensea far Subunit feels the first heme’s bond Quiver, the chains pull, O2 binds Easier. Cooperativity, an allosteric Protein. Third, the repeated references to nature as a tinkerer, even the title of the poem, suggest that chemical evolution is a primary theme of the poem. Fourth, whether comparing internal combustion engines to hemoglobin or discussing our feeble attempts to learn nature’s secrets, the poem compares the scientific efforts of mankind to the accomplishments of nature. Finally, there is a very human aspect that looms over this poem. The author refers to someone, a friend or acquaintance perhaps, who committed suicide when he sealed up a garage, turned on an automobile engine, and breathed in lethal carbon monoxide. This tragic outcome is connected to the fact that nature, “the tinkerer”, did not succeed in making carbon monoxide nontoxic but only reduced its toxicity. The general discussions that followed were a pleasant surprise for the organizers. Students, normally disinclined to speak up in a science classroom setting, readily contributed. Comments covered a wide range of subjects. A few of the many topics discussed included: (i) the slight variation of hemoglobin in various organisms; (ii) the idea of chemical evolution; (iii) humanity’s inability to effect chemical transformations as effectively as nature; (iv) the contrast between the human side of the poem, with all that is unknowable, and the science side of the poem, with all the precise details that can be parsed with great accuracy.

songs to their class, rewriting the lyrics to reflect chemistry topics.9 They have had students keep journals, create paintings, use music, and write poems about chemistry.10−14 There are also contests specifically for poems about chemistry.15,16 But we have not noticed the use of the critical reading of a published poem as a means of enhancing or reinforcing the understanding of chemistry subject matter. There is a small set of poems that could serve this purpose. These include poems with direct chemical references,8,17−19 and poems that refer obliquely to chemical topics, such as Carl Sandburg’s poem, “Under”, with its references to the second law of thermodynamics.20 There are also whimsical examples, such as chemical clerihews.21,22 This article relates our reading of a poem, by 1981 Chemistry Nobel Laureate Roald Hoffmann, to science students and local high school teachers and the discussion that resulted. The poem, “Jerry-Built Forever” from the book Gaps and Verges18 is presented at the end of the article with the author’s and publisher’s permission.



PARTICIPANTS



POETRY READING AND DISCUSSIONS

Article

While teaching an upper-level elective course on bioinorganic chemistry, one of us (R.S.H.) decided to use this poem for a poetry reading to expose students to literary ideas regarding hemoglobin. The goal was to use a poetic lens to focus attention on this iconic protein from different scientific points of view and also to introduce humanistic aspects, including the poisonous nature of CO and its occasional use in suicide attempts. A poet in the English Department (R.K.C.) offered to read the poem and assist with the literary analysis. We have since presented the poem to two classes of bioinorganic chemistry, two classes of inorganic chemistry, and a summer class for local high school science teachers. Student scholarship recipients in Holy Cross’s NSF S-STEM (Scholarship in Science, Technology, Engineering, and Mathematics) program were also invited to attend. There were between 20 and 35 attendees at each of the presentations.

The organizers planned the event to be low-key and fun, yet informational and thought provoking. Students were provided the poem beforehand and encouraged to read it carefully, so they would be engaged during the presentation and contribute to the conversation after the reading. At the onset, one of us (R.S.H.) gave a 10-min lecture on the structure, function, and allosteric movements of hemoglobin, using pictures and animations for illustration. This helped teach or remind attendees that hemoglobin functions like a “molecular lung”, as Max Perutz described it, and that this motion relates to the cooperativity of the hemoglobin molecule.23 As a further way to visualize the three-dimensional structure of hemoglobin, a glass cube containing the accurate, laser-etched structure of deoxyhemoglogin (pdb file 1A0Z),24,25 was passed around the classroom. After the scientific review, one of us (R.K.C.) gave a short explanation on how to read and analyze a poem. He then read the poem stopping after each section for comments. After reading all five sections, the group had a lengthy discussion. 216

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CONCLUSION These readings more than met the expectations of the two organizers. This is clearly an interesting way to examine a topic in chemistry. It attracted much student interest and engaged students’ attention; reading about a scientific subject when it is presented in a poetic fashion is fun for science students. They take subjects other than chemistry and biology, including English courses, and they enjoy using their talents in the humanities to think about important chemical concepts in a nontraditional way. Students also see faculty members from different disciplines work together, in this case to analyze a poem. Each faculty member has a different perspective and a different way of thinking that is on display during the event. It is also an opportunity to see members from each of C. P. Snow’s Two Cultures working together, using the skills of each to bring deeper meaning to a poem.26 Jerry-Built Forever 1 We think that all that matters Can’t be deep, but chunk-toKnowledge-chunk in subsurface Veins, and we, mind-armed miners Search/dance to lift earth cover, Free the plan. The world, oh it Waits patiently to be known, And we do know much: what The bombardier beetle sprays; The salts, silts and organics, The gradients in the Azov Sea; far bangs and dodges Of light in space; how vitamin B12 twists one pyrrole ring As it is made. Terra incogNita shrunk to the way the birch Bark peels and why he dressed In white the night he sealed The garage door cracks and Turned on the engine... 2 This biconcave bialy platelet Of the erythrocyte, the red Heart of the blood, holds the oxygen Carrier, hemoglobin. Four coiled Polypeptide chains, four subunits Changing pairwise twice in the fetus To let it soak up placental O2 Steadily. Each chain a globular Protein, juxtaposed twining Of helical segments, predestined Kinks, sequences of amino acids Alike in sperm whale and horse, A meander of bonds around The flat disc that colors all...heme. The active site, the oxygen binding Site, a porphyrin, iron. Oxygen, Enflamer, winds to a pocket Molded by protein, binds iron, moves It in consummation, chains Tethering heme tensea far Subunit feels the first heme’s bond Quiver, the chains pull, O2 binds Easier. Cooperativity, an allosteric

Protein. In 1937 Not long before the war, Felix Haurowitz watched crystals Of deoxyhemoglobin Shatter on oxygenation. 3 Beauty whirls rococo In fussy chains round The oxygen pocket; beauty Cambers simplethe iron Hub of heme. If God’s Plan for all this function Be heresy, at least let What came, chanced, to be Be best. Heme, myo- and hemoGlobins, vertebrates O2 Transport proteins, subunits’ Trim fit linkevolved. 4 Carried by blood, carrying Electrons, life-empowering Oxygen. Elsewhere, in engines It’s sucked into carburetor Trains, there to mix with branched Heptanes, octanes, another kind Of feedstock. Sparked, it burns Things in controlled explosions, A human specialty. And what Thermochemistry says should end In greening CO2 and steam, in Incomplete combustion partly Goes to CO, carbon monoxide. This odorless diatomic tressPasser sweeps into bronchia, brashly Binding 200 times better Than O2. A free ride on deoxyhemoGlobin down arteries, right past Cells that long for the other, can’t Wait too long before shutdown. 5 So a life ends. That wise blood, A million years in the making, it Should have fought, that oxygenStarved blood. But Nature’s A tinkerer, a shanty-town contractor, Filer of mis-fit gears, the original Found artist. In oxygenated Salty soups, lightning-lit, when Molecules swam to be shaped, And vines groped for the sun, she Took anything that worked, or the first That passed the million destructions Of her sweet time lab. No whiteCoated intelligences to hurry her Or remind her of the carbon Monoxide that was not there. Roald Hoffmann (Reprinted with permission of the University Press of Florida.) 217

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Notes

The authors declare no competing financial interest.



ACKNOWLEDGMENTS R.S.H. acknowledges the National Science Foundation for a STEM grant (DUE-0728549). The authors thank Roald Hoffmann for permission to include the text of the poem “Jerry-Built Forever” with this article.



REFERENCES

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