 Helpful microbes in your daily life. Lee and Pat are busy microbiology students. The other day, Lee had a yogurt smoothie and a salami sandwich on rye bread for lunch. At the end of the day, Lee went to Pat's house for dinner. Pat lives on a dairy farm, and Lee could see the cows peacefully chewing their cud in the field. Pat had prepared a delicious meal of lasagna with cheese and a salad with wine vinegar dressing. Over dinner, Lee and Pat discussed the joys and frustrations of gardening, the benefits of good compost, and BT sprays to keep caterpillars away. Pat is diabetic, so after eating, Pat checked her blood sugar and needed to inject some insulin. Then Pat and Lee washed the dishes. Unfortunately, the drain was slow, but Pat pulled out some enzymatic drain cleaner to help clean out the deposits in the plumbing and speed the dishwater on its way to the septic tank. Yogurt is made from milk that has been fermented by bacteria. Salami and some sausages are fermented meats. The acids produced by the bacteria give these sausages a distinctive flavor and also act as a preservative. Yeasted breads get their light, spongy texture from the carbon dioxide bubbles produced by yeast in the dough. Cows have symbiotic bacteria living in their stomachs. The bacteria help break down cellulose and other plant components so that the cows are able to obtain sufficient nutrients from foods like grass and hay. Cheese is produced by adding bacterial cultures and renin to milk. Different strains of bacteria and molds, as well as different ripening conditions, are used to produce the wide range of cheeses from brie to cheddar to blue cheese. Wine vinegar is produced by alcoholic and acetic acid fermentation, done by yeasts and bacteria. Composts consists of organic material that has been decomposed by a variety of microbes to produce a rich soil-like mixture. BT sprays contain spores of the bacterium bacillus tringiensis. When an insect ingests the spores, the spores germinate into vegetative bacteria that produce a toxin which kills many insect larvae but is harmless to mammals. BT sprays are used in organic gardening and are also used to control gypsy moth larvae. Synthetic human insulin is produced by bacteria that have been genetically engineered to produce human insulin. Enzomatic drain cleaners contain bacterial spores. The spores germinate into vegetative cells in the moist environment of the drain and feed off material that contributes to build-up in plumbing. Septic tanks and municipal water treatment plants rely on microbes to break down waste and remove solid and dissolved substances from wastewater. You have completed helpful microbes in your daily life.