Jayant Radhakrishnan
Darien, Illinois, United States

Andrew Moyer, in his Peoria laboratory, discovered the process for mass producing penicillin. USDA-ARS National Center for Agricultural Utilization Research. Public domain.

 

“Though she be but little, she is fierce.” 
— William Shakespeare, A Midsummer Night’s Dream  

 

The adage “out of sight, out of mind” appears to have been coined for microbes. We only think about them when they cause havoc, as in the current pandemic. Lately the situation seems to be changing, albeit slowly. Three states in the US – Oregon, New Jersey, and Illinois – and one country, India, have chosen to recognize some important microbes. 

Ten years ago, the Government of India resolved that in an overwhelmingly agrarian society, the younger generation must understand the importance of microbes and the negative impact of pesticides and  chemical fertilizers. They assembled a sixteen-coach train, the “Science Express Biodiversity Special,” that stopped at various cities around the country. At these stops, Indian children were asked to vote for a “National Microbe.” They voted for Lactobacillus delbrueckii subsp. Bulgaricus.¹ This lactobacillus is a Starter Lactic Acid Bacterium (SLAB) present in yogurt cultures. It survives passage through the stomach because it is resistant to gastric acid, and through the small intestine, as it is not denatured by bile or pancreatic secretions. Under anaerobic conditions, it is able to ferment sugar substrates into lactic acid. It also has probiotic potential as it is present in adequate amounts in the terminal ileum² and may stimulate polyclonal antibody production, thus increasing resistance to infection.³ 

In the US, Oregon was the first to designate a “State Microbe.” They recognized a fungus that contributed tremendously to the state coffers. Saccharomyces cerevisiae (brewer’s or baker’s yeast) was given the title in 2013 because it is integral to the craft beer brewing culture, which brings as much as $2.4 billion a year into the state. Brewer’s yeast is also needed to make bread, cheese, and distilled spirits because it converts fermentable sugars into ethanol and carbon dioxide. According to Mark Johnson, the state legislator who launched this initiative, “It’s the bedrock of a lot of fun and enjoyable products.”⁴ 

Wisconsin, on the other hand, failed to designate Lactococcus lactis, a gram-positive coccus, as its state microbe in 2010.⁵ They produce over two billion pounds of cheese every year and this organism has a crucial role in the cheese industry. It is also vital in the production of buttermilk and sour cream and may be used to ferment vegetables. It is unclear why the initiative failed in the state senate. 

Since 2013, Hawaii has tried and failed to have two organisms designated as state microbes.⁶ The first is Flavobacterium akiainvivens, a gram-negative bacterium. This organism was first found in the ākia shrub, which is native to Hawaii. Ancient Hawaiians utilized the shrub for many purposes, including as a medicine. It failed to be designated because the next year, a competing proposal was introduced nominating Aliivibrio fischeri (also known as Vibrio fischeri), a gram-negative bacterium. This organism lives symbiotically with the Hawaiian bobtail squid and its bioluminescence enables the squid to hunt at night. Vibrio fischeri was also instrumental in other discoveries such as mechanisms that determine beneficial interactions between microbes and their hosts, and the phenomenon of quorum sensing, whereby bacteria can adjust gene expression based upon cell density. However, Vibrio fischeri could not be designated a state microbe because it is not confined to Hawaiian waters unlike its partner, the bobtail squid, which is native to Hawaii. 

In 2019 New Jersey recognized Streptomyces griseus as its state microbe.⁷ It is a mycelium-forming Actinobacterium that was found in “heavily manured” field soil in New Jersey in 1916 when Selman Waksman (1888-1973) was determining the microbiological population of the soil. His group isolated streptomycin in 1943 and presented it to the world in 1944. It was the first antibiotic that was bactericidal to a wide range of gram-positive and gram-negative bacteria. Waksman’s group had previously discovered streptothricin, which also acted upon gram-positive and gram-negative organisms but did not have as broad a spectrum.⁸ Streptomycin changed the therapeutic landscape, especially in the treatment of tuberculosis. In the US alone, streptomycin reduced tuberculosis deaths from 194 per 100,000 in 1900 to 9 per 100,000 in 1955.⁷ 

Waksman received the Nobel Prize in 1952 for discovery of the organism and the development of streptomycin. In addition to streptomycin (1943), Waksman was also involved in isolating other antibiotics such as actinomycin (1940), clavacin, streptothricin (1942), grisein (1946), neomycin (1948), fradicin, candicidin, and candidin.⁹ 

The latest state to adopt a microbe as its own is Illinois. On August 17, 2021 the Governor of Illinois signed into law Penicillium Rubens NRRL 1951 as the State Microbe.¹⁰ Credit for initiating the process and convincing politicians to recognize the mold and the pioneering work carried out in Illinois goes to Gary Kuzniar, a physical science technician, and Neil Price, a chemist, who set up the Illinois State Microbe Designation Project in 2019. 

Alexander Fleming reported on his discovery of penicillin in 1929¹¹ but it was forgotten for years, as the molecule was unstable and the antibiotic difficult to make in large amounts. After sulfonamides were introduced in 1935 and their great value in treating bacterial infections became apparent, interest in developing penicillin was resurrected. Ernst Chain and Howard Florey obtained Fleming’s Penicillium strain, concentrated it, and succeeded in creating a stable form of penicillin. They published their results in 1940.¹² As the World War was raging, it became apparent that large amounts of the antibiotic would be needed to keep injured Allied soldiers from dying of sepsis. The problem was that the strain of bacteria in the UK did not produce large amounts of antibiotic. In fact, the first patient treated with it in 1941 is said to have died because they ran out of penicillin. Furthermore, there were monetary restraints and a shortage of supplies in the UK because of the war. The US and UK governments decided to collaborate, and huge sums of money were poured into the mass production of penicillin in the US.¹³ In 1941 Howard Florey and Norman Heatley carried their mold to the United States Department of Agriculture (USDA) Northern Regional Research Laboratory (NRRL), now known as the National Center for Agricultural Utilization Research (NCAUR) in Peoria, Illinois. This laboratory is the largest of the Agricultural Research Service (USDA-ARS) research centers. At the laboratory in Peoria, experts in deep-tank fermentation had been successful in growing mold by using corn steep liquor, a byproduct of alcohol production, along with other nutrients. Between 1941 and 1943 they isolated high-yielding strains of the mold, the highest being from a strain found in a moldy cantaloupe in the local market.¹⁰ It was not revealed until after the war that this strain was also sent to the geneticist Milislav Demerec (1895-1966) at the Carnegie Institute of Washington (now Cold Spring Harbor Laboratory, Long Island, New York). Demerec had perfected the art of inducing genetic mutations in Drosophila virilis, a variety of fruit flies, by irradiating them. By radiating the mold, he increased its yield tenfold because the mutant strain was able to grow abundantly, even when submerged in a vat of the nutrient fluid. The natural variety grew only when floating on the surface.^{14, 15} As a result, the Allies had ample supplies of penicillin available for the troops on D-Day. 

Although Fleming called his strain of the mold Penicillium notatum and later it was renamed Penicillium chrysogenum, recent genomic studies of Fleming’s original isolate have demonstrated that Fleming’s and the American strains are all Penicillium rubens. Comparison of the strains revealed that the difference in yield of penicillin was caused by amino acid divergence in the main effector genes for producing penicillin G (pcbAB, pcbC, and penDE) while conserving a suite of regulatory genes.¹⁶ 

Microbes are extremely versatile. Therefore, even one that is dangerous and destructive under certain conditions can help us solve problems in other situations. We have already seen how fungi such as Penicillium that spoil food can be lifesaving under the right circumstances. Similarly, there are other organisms that are being studied as therapeutic agents, particularly for cancers. When microbes are used against cancer, three basic mechanisms can come into play. First, they could be directly cytotoxic to tumor cells. Secondly, they may attack the vasculature that nourishes the tumor. Finally, they might induce cell destruction by activating an immune response against the tumor. One of the first examples of immunotherapy for cancer was William B. Coley’s good results upon injecting Streptococcus pyogenes in patients with osteosarcoma in the 1890s. Because of skepticism and fear on the part of other doctors and the introduction of radiation and chemotherapy as adjuncts in the treatment of cancer, “Coley’s toxins” disappeared from the medical armamentarium. 

The best microbes for destroying tumor cells are obligate anaerobes such as those of the Clostridium genus (after removing the α toxin), and facultative anaerobes such as Salmonella typhimurium. Obligate anaerobes function in anoxic tumor tissue and are safer for the patient as they cannot survive in oxygenated healthy tissue. The disadvantage is that they have to be injected directly into the tumor. This presents a problem if the tumor is difficult to reach or there are multiple tumors, as may be the case with metastases. Facultative anaerobes can infect hypoxic and oxygenated tissues; thus, they pose the threat of infecting healthy tissues. The advantage of a facultative anaerobe is that if it survives passage through the stomach and small intestine, it becomes a candidate for oral delivery. An example is Salmonella.¹⁷ 

Microbes are also useful for cosmetic purposes; there is a tongue-in-cheek suggestion that Los Angeles should name Clostridium botulinum or BOTOX their “city microbe.”⁶ 

Clearly, many of these miniscule organisms have an outsized impact on the world. 

 

Bibliography

1. Press Information Bureau, Government of India, Ministry of Environment, Forest and Climate Change. Education for Biodiversity Conservation CoP-11, Hyderabad 18 October 2012. 
2. Lick S, Drescher K, Heller KJ (2001): Survival of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus in the terminal ileum of fistulated Götingen minipigs. Applied and Environmental Microbiol 67(9):4137-4143 doi: 10.1128/AEM.67.9.4137–4143.2001.
3. Easo JG, Measham JD, Munroe J, et al (2002): Immunostimulatory actions of Lactobacilli: Mitogenic induction of antibody production and spleen cell proliferation by Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus acidophilus. Food and Agricultural Immunology 14(1)73-83 doi:10.1080/09540100220137682.
4. Shute N (2013): Craft-Beer-Crazy Oregon poised to name official State microbe. NPR WBEZ, Chicago April 5, 2013. 
5. Norris M (2010): No state microbe for Wisconsin. Heard on all things considered. NPR WBEZ, Chicago April 28, 2010. 
6. Cave J (2014): Hawaii and other states calling dibs on official state bacteria. Huffington Post April 3, 2014. 
7. Associated Press (2019): New Jersey gets official State microbe: Streptomyces griseus. May 11, 2019. 
8. Schatz A, Bugie E, Waksman SA (1944): Streptomycin, a substance exhibiting antibiotic activity against Gram-positive and Gram-negative bacteria. Proc. Soc. Exp Biol and Med. 55(1):66-69 doi.org/10.3181/00379727-55-14461. 
9. Selman A. Waksman – Biographical. NobelPrize.org. Nobel Prize Outreach AB 2022. https://www.nobelprize.org/prizes/medicine/1952/waksman/biographical/.
10. Suszkiw J (2021): Penicillium strain named state microbe of Illinois. US Department of Agriculture Research Service. August 20, 2021. https://www.ars.usda.gov> news > research-news > 2021.
    
11. Fleming A (1929): On the antibacterial action of cultures of a penicillium, with special reference to their use in the isolation of B. Influenzæ. Brit. J Experimental Pathol. 10(3):226-236. 
12. Chain E, Florey HW, Gardner AD, et al (1940): Penicillin as a chemotherapeutic agent. Lancet 236(6104):226-228. doi:https://doi.org/10.1016/S0140-6736(01)08728-1. 
13. Fleming A (1945): Penicillin Nobel Lecture. NobelPrize.org. Nobel Prize Outreach AB 2022. https://www.nobelprize.org/prizes/medicine/1945/fleming/lecture/.
14. Stallard B (2019): Cold Spring Harbor Laboratory, Long Island NY Home page. October 29, 2019 
15. Demerec, Milislav: www.encyclopedia.com › science › demerec-milislav. 2022. 
16. Pathak A, Nowell RW, Wilson CG, et al (2020): Comparative genomics of Alexander Fleming’s original Penicillium isolate (IMI 15378) reveals sequence divergence of penicillin synthesis genes. Nature Research Scientific Reports 10:15705 doi.org/10.1038/s41598-020-72584-5. 
17. Weiman S (2014): (ed) Fox J. Harnessing the power of microbes as therapeutics: Bugs as drugs. Report on an American Academy of Microbiology Colloquium held in San Diego, CA, in April 2014.

 

---

 

JAYANT RADHAKRISHNAN, MB, BS, MS (Surg), FACS, FAAP, completed a Pediatric Urology Fellowship at the Massachusetts General Hospital, Boston following a Surgery Residency and Fellowship in Pediatric Surgery at the Cook County Hospital. He returned to the County Hospital and worked as an attending pediatric surgeon and served as the Chief of Pediatric Urology. Later he worked at the University of Illinois, Chicago from where he retired as Professor of Surgery & Urology, and the Chief of Pediatric Surgery & Pediatric Urology. He has been an Emeritus Professor of Surgery and Urology at the University of Illinois since 2000.

 

Winter 2022  |  Sections  |  Infectious Diseases