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“Never Alone: From Microbes to Millipedes, Camel Crickets, and Honey Bees, the Natural History of Where We Live,” by Rob Dunn, Basic Book, NY, 2018. This 323-page hard back describes the modern world of microbiology, the microbes that surround every aspect of life. Dunn is professor of applied ecology at North Carolina State University. He provides a highly readable overview of research in microbiology. We get a snapshot of the modern professional scientist who is creative in selecting interesting subjects but works with a team of students, post-docs, and other scientists. Omitted is the competition for funding usually through grant requests to government agencies.The story begins with Anthony van Leewenhoek, a Dutch fabric salesman, who discovered bacteria in 1676. He used a primitive microscope but was skilled and persistent in his studies. He began with a peppercorn but over five decades investigated many things around him. His work was published by the Royal Society.A chapter describes John Snow’s use of maps in 1854 to prove that cholera was spread by contaminated drinking water rather than mysterious miasmas. Maps are now used by epidemiologists to learn where disease originated. Diseases associated with chronic inflamation include Crohn’s disease, inflammatory bowel disease, asthma, allergies and multiple sclerosis. These diseases are more common in affluent areas. They become about twice as common every two decades since 1950, more so in wealthier countries. A follow-up study evaluated allergies in Karelia Finland, where a national border divided the region into traditional Russia and modern Finland. Traditional living found greater biodiversity in the plants around homes and fewer allergies. A related study compared Amish and Hutterite communities in Pennsylvania. The Amish are more traditional, and they had lower rates of asthma. Dunn also cites the treatment of c difficile patients with fecal transplants. Patients treated with oral antibiotics become susceptible to c difficile because good bacteria are eliminated. Fecal transplants reestablish healthy colonies.When you kill off living species but leave their food, tough species survive and thrive. Ecologists call this competitive release. Stachybotrys chartum is the black toxic mold often the subject of insurance claims in buildings. The mold was found in half of the samples when new wall board (purchased in Denmark) was soaked in sterile water for 70 days. Neosarorya hiratsuke, a fungus implicated in Parkinson’s disease, and Chaetomium globosum, an allergen, were also found.The author notes that scientists often focus their investigations in exotic areas and overlook the species close to home. Dunn and team undertook a study of insects found in eleven homes. In his own house they found 100 species of anthropods. Similar numbers were found in houses in San Francisco and Sweden. Ditto Peru, Japan, and Australia. The list included many varieties of flies, many likely new to science. In Raleigh, 14 species were identified from flies to mites and ticks. Houses with dogs had more bacteria. Some species of bacteria were more rare when cats were present.A recent study found that silverfish have enzymes that can digest cellulose. Klebsiella bacteria spread by house flies with their eggs produce compounds that kill fungi. Ants produce antibiotics in their venom glands. Dunn wonders if some of these might be useful as drugs. The thief ant was found to produce antibiotics effective against MRSA related bacteria.Yeasts in vineyards overwinter in the guts of wasps. A study looked for new yeasts to brew beer for a festival. A student found more than 100 yeasts. One could produce sour beer in a month rather than years. Some yielded breads with unique aromas and flavors. The German cockroach is described in a chapter. Its survival is closely tied to humans. A scientist at Clorox studied the baits used to control cockroaches. Usually glucose is the attractant for a pesticide. In one apartment cockroaches were immune to the bait. The cockroaches had developed an aversion to glucose. Fructose bait was effective. Natural selection leads to resistance to pesticides. In Africa, social spiders are brought into houses to control flies. In a trial at the Plague Research Laboratory, the fly population declined by 60% in three days in the presence of the spiders. Certain wasps can control cockroaches; a fungus can control bed bugs. In Glasgow, mice infected with Toxoplasma gondii were more active on a hamster wheel. Toxoplasma is associated with cats which are part of its life cycle. Infection is thought to create hyperactivity in animals making them easier for cats to catch. A personality test found that infected men were more likely risk takers. The infection is associated with schizophrenia. In the US 20% of adults are thought to be infected with toxoplasma. In the 1950s, Type 80/81 staphylococus aureus was dangerous to babies. A nurse working in the hospital was a carrier. Babies exposed after 24 hrs were not infected. Strain 502A was protective. 502A produced enzymes that prevented pathogens from forming biofilms. For a while babies were inoculated with 502A for protection. In the end, complications arose as some babies became infected. Antibiotics became the preferred treatment.An experiment placed agar in a two by four ft tray with regions of none to low to high antibiotic content. Bacteria grew rapidly in the antibiotic free region, but then a mutation occurred allowing the bacteria to grow in the low antibiotic region, and later the high antibiotic range. Bacteria mutate constantly. In the experiment the needed mutations occurred in eleven days.Resistance to antibiotics caused by over use is a continuing concern. In 1987, 20% of staph infections were resistant to methicillin; by 1997, more than 50%; by 2005, 60%. The number of infections is also increasing. The worst antibiotic resistant bacteria are usually found in hospitals where they are constantly challenged by antibiotics.Handwashing is discussed. The skin is covered by a layer of bacteria. Washing even with soap does not remove this layer. But washing for at least 20 seconds removes newly arriving bacteria. A final chapter studies the biodiversity of food related microorganizms. Many foods involve fermentation. The culture used gives the food unique flavors and characteristics. Dunn especially enjoys Korean cooking which uses numerous manual manipulations. The cook’s microbes affect the dishes. Rather than the bacteria that usually covers the skin, bakers skin was covered with microbes unique to their bakery. Sour dough starters are maintained by many for family recipes. These are unique. The same applies to kimchi, beer, bread, sauerkraut and dozens of other foods.This is an excellent introduction to the bio-world around us. Microbiology students will find it especially informative. References. Index. Illustrations.
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