{'fraction_non_alphanumeric': 0.030601659751037343, 'fraction_numerical': 0.006742738589211619, 'mean_word_length': 4.724035608308605, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Profile of Bob B. Buchanan

On a clear June day in 1975, Bob Buchanan and two Oslo colleagues pulled up water samples from a lake in Norway, examining the microorganisms growing at various depths. “When we got to 6 meters,” Buchanan recalls, “there was a band of Chlorobium growing,” referring to a genus of green bacteria (now called Chlorobaculum ) that belongs to a unique class of organisms called photolithotrophs. These bacteria require sunlight for photosynthesis but obtain cellular reductants from sulfur compounds rather than water. The bacteria buck the traditional chemical pathways for energy production and carbon fixation and instead use pathways discovered by Buchanan, a member of the National Academy of Sciences and emeritus professor at the University of California, Berkeley.



Bob B. Buchanan. Image courtesy of Bob B. Buchanan.



Buchanan was born in 1937 in Richmond, Virginia. Fearing for the family’s safety during World War II, Buchanan’s mother took him and his two older sisters to a family farm in Southwest Virginia, near the Appalachian town of Glade Spring, while his father remained in Richmond to work. Farm life shaped Buchanan’s early years. He cared for pet lambs as a child and put himself through college by growing beans and milking cows. “By hand!” he says.

Buchanan attended nearby Emory and Henry College, where he took a bacteriology class from zoologist Lee T. Douglas. Under Douglas’ mentorship, Buchanan’s interest in microorganisms blossomed. “I remember seeing a culture of Bacillus subtilis , a bacterium that can grow with or without oxygen, stained with crystal violet under a simple microscope,” Buchanan says. “The cells were so brilliant; that’s what I wanted to work with.” He was fascinated by the concept of life without oxygen.

Buchanan moved to Duke University in 1958 for his graduate work. He studied Actinomyces , facultative anaerobes known to infect cattle …