Students in agronomy (plant technologies) and soil science may know that genes from bacteria like Agrobacterium can be used in bio-engineering to develop disease resistance in plants. Also soil microbes are helpful in breaking down (decomposition) of dead organic material in the soil resulting in addition of nutrients to the soil. Still other soil microbes release minerals that are attached to soil particles and/or fix nitrogen. Since most nitrogen is in the atmosphere and not available to plants, microbes must combine the nitrogen with oxygen to make a soluble molecule called a nitrate which can be taken in through the roots.

During the breakdown of carbohydrates by microbes, numerous products like acids and alcohols may be produced. The production of these chemicals is a major industrial use of microbes. In the fermentation process, many foods including cheese and silage (animal food often used in the dairy industry) are the result of microbe activity. Pasteur was an early microbiologist who studied fermentation of grapes resulting in the production of wine. Later he introduced pasteurization (heating) to eliminate additional microbial fermentation so the wine "did not go bad." Saccharomyces (yeast) and Zygomonas (a bacterium) are commonly used to make beer and tequilla respectively.