Final answer:
Grow anaerobic bacteria in the lab, microbiologists typically use anaerobic jars to create oxygen-free environments and thioglycolate tubes to observe differential growth patterns that indicate oxygen requirements. These methods are crucial for cultivating bacteria with specific needs concerning oxygen presence.
Step-by-step explanation:
Methods for Growing Anaerobic Bacteria in the Lab
Anaerobes are bacteria that grow in the absence of oxygen. To cultivate these organisms successfully in the laboratory, microbiologists must use techniques that exclude oxygen. Two commonly used methods for growing these bacteria are:
- Anaerobic jars: This equipment is designed to grow obligate anaerobic bacteria, which are killed by the presence of oxygen. An anaerobic jar creates an environment devoid of oxygen, often by using a chemical reaction to remove oxygen from the sealed jar, allowing anaerobes to thrive.
- Thioglycolate tubes: This is a medium that can show differential growth patterns, illustrating the oxygen requirements of various bacteria. For obligate anaerobes, growth will occur at the bottom of the tube where the concentration of oxygen is lowest, while other categories of anaerobes may grow differently in the tube depending on their oxygen tolerances.
For facultative anaerobes like E. coli, the laboratory conditions can be adjusted to allow growth in the presence or absence of oxygen by controlling the ratios of oxygen and nitrogen gases. Understanding these growth requirements is essential in microbiology for the cultivation and study of various bacterial species, each with their unique physiological needs regarding oxygen.