Alphaproteobacteria is a class of Proteobacteria that includes several obligate and facultative intracellular pathogens, such as the rickettsias. Additionally, some members of this class are oligotrophs capable of surviving in nutrient-poor environments, while others can convert atmospheric nitrogen into nitrites to make it usable for other forms of life.

Alphaproteobacteria

An oligotroph is an organism capable of surviving and growing in environments with very low levels of nutrients, such as deep oceanic sediments, glacial ice, or deep undersurface soil.

Google

The maximum growth of a microbial population is dependent upon its specific ideal physical and chemical conditions.

Growth Conditions

https://openstax.org/details/books/microbiology/

Microbiology covers the scope and sequence requirements for a single-semester microbiology course for non-majors. The book presents the core concepts of microbiology with a focus on applications for careers in allied health. The pedagogical features of the text make the material interesting and accessible while maintaining the career-application focus and scientific rigor inherent in the subject matter. Microbiology’s art program enhances students’ understanding of concepts through clear and effective illustrations, diagrams, and photographs.

Microbiology is produced through a collaborative publishing agreement between OpenStax and the American Society for Microbiology Press. The book aligns with the curriculum guidelines of the American Society for Microbiology.

OpenStax Microbiology Textbook

- Temperature 
- pH
- Osmotic Pressure
- Barometric Pressure
- Light 
- Oxygen (environmental)

Physical Factors Influencing Microbial Growth

Growth media, also known as nutritional media, are used to grow microorganisms in a laboratory setting and can be liquid, solid, or gel-like. A growth medium provides essential nutrients for microorganisms to grow and reproduce, including water, various salts, a source of carbon (like glucose), and a source of nitrogen and amino acids (like yeast extract). The ingredients in a growth medium can be modified to cultivate unique types of microorganisms.

Learn Before

Related

Learn After