Cyanobacteria: Eubacteria or Algae?

Introduction:
Cyanobacteria, also known as blue-green algae, are a group of prokaryotic microorganisms that obtain energy through photosynthesis. They are found in a wide range of habitats, including freshwater, marine, and terrestrial environments. Cyanobacteria play a crucial role in global carbon and nitrogen cycles and have been present on Earth for billions of years. However, there is often confusion regarding their classification as either eubacteria or algae.

Eubacteria:
Eubacteria, also called true bacteria, are a large and diverse group of prokaryotic microorganisms. They are characterized by their cell structure, lack of a nuclear membrane, and presence of peptidoglycan in their cell walls. Eubacteria encompass a wide range of bacteria, including both beneficial and pathogenic species, such as Escherichia coli and Staphylococcus aureus.

Algae:
Algae, on the other hand, are a diverse group of eukaryotic organisms that contain chlorophyll and other pigments, allowing them to undergo photosynthesis. They can be unicellular or multicellular and are typically found in aquatic environments. Algae include various groups, such as green algae, red algae, and brown algae, each with distinct characteristics and ecological roles.

Classification of Cyanobacteria:
Cyanobacteria were historically classified as algae due to their ability to photosynthesize and their presence in aquatic environments. However, with advancements in molecular biology and genetic studies, it has been determined that cyanobacteria are actually prokaryotic organisms belonging to the domain Bacteria. They are considered a phylum within the kingdom Monera, which includes other bacteria as well.

Key Differences:
1. Cell Structure: Cyanobacteria, being prokaryotes, lack a true nucleus and membrane-bound organelles, which are present in eukaryotic algae.
2. Pigmentation: Cyanobacteria contain pigments similar to those found in algae, such as chlorophyll a and phycobiliproteins. However, the pigments in cyanobacteria are located in specialized structures called thylakoids, while in algae, they are found in chloroplasts.
3. Genetic Composition: Cyanobacteria possess a unique genetic composition that distinguishes them from algae. They have circular DNA and lack introns, which are commonly found in eukaryotes.

Conclusion:
In conclusion, cyanobacteria should be classified as eubacteria rather than algae. Despite their ability to photosynthesize and their resemblance to algae in some aspects, cyanobacteria are prokaryotic microorganisms with distinct cellular and genetic characteristics. Their classification as eubacteria is supported by molecular and genetic evidence.

It belongs to algae group. ...it is also known as blue green algae