You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "where can you find bacteria that are not harmful?" whose answer is the gut flora.
Each document should contain about 30 words, and these documents should contain useful information.

Query: environments where bacteria are not harmful
Useful Output:

Doc 1: Some bacteria, such as those in your gut, help keep you healthy. Other bacteria may cause bacterial infections and require treatment.
Doc 2: Microbes live in soil, water, air, plants, rocks, and animals. They even live in extreme environments such as hot springs, deep ocean thermal
Doc 3: They inhabit virtually every environment on Earth, including many places where no other organisms can survive. Diagram showing diverse bacterial
Doc 4: Many bacteria (and the Bad Ones are no exception) grow happier when they grow together forming biofilms that will stick to living (teeth
Doc 5: Ground water has traditionally been considered to be the water source least susceptible to contamination by indicator bacteria or human