Which of the following proteobacteria are oligotrophs?
A Alphaproteobacteria
B Betaproteobacteria
C Gammaproteobacteria
D Deltaproteobacteria
E Epsilonproteobacteria
The correct answer and explanation is:
The correct answer is A) Alphaproteobacteria.
Explanation:
Oligotrophs are organisms that are adapted to live in environments with low concentrations of nutrients, particularly in environments with limited available nitrogen, phosphorus, or carbon. These organisms have specialized mechanisms to survive and thrive in such nutrient-poor conditions.
Alphaproteobacteria, a class within the proteobacteria group, are well-known for their ability to thrive in oligotrophic environments. They are often found in environments such as oceans, lakes, and soil, where nutrient availability is limited. Many Alphaproteobacteria species have adapted to these conditions by developing metabolic pathways that allow them to efficiently utilize low concentrations of nutrients.
Some key features of Alphaproteobacteria that make them oligotrophs include their ability to fix nitrogen, process organic compounds efficiently, and survive in low-nutrient conditions. Additionally, some species in this group are involved in symbiotic relationships with plants and animals, where they help facilitate nutrient cycling in nutrient-poor soils or other habitats.
The other groups listed in the question, such as Betaproteobacteria, Gammaproteobacteria, Deltaproteobacteria, and Epsilonproteobacteria, do not share the same level of adaptation to oligotrophic environments. These groups are more commonly associated with environments where nutrients are more readily available, such as in water bodies with higher nutrient loads or in environments with higher organic matter.
For example:
- Betaproteobacteria are often found in environments with moderate to high nutrient availability.
- Gammaproteobacteria include many bacteria that are pathogens or involved in nutrient-rich environments.
- Deltaproteobacteria are often found in environments with organic matter or where sulfate reduction occurs.
- Epsilonproteobacteria are typically associated with gastrointestinal environments or other specialized niches where nutrients are not as limiting.
Therefore, Alphaproteobacteria are the best representatives of oligotrophic bacteria within the proteobacteria group.