Cyanobacteria, also known as blue-green algae, are a diverse group of microorganisms belonging to the phylum Cyanobacteria. They are photosynthetic bacteria that obtain their energy through the process of photosynthesis, converting sunlight into chemical energy. They are one of the oldest known forms of life on Earth, with fossil records dating back over three billion years.
Cyanobacteria are typically found in diverse habitats, such as freshwater, marine environments, and terrestrial ecosystems, including extreme environments like hot springs and Antarctica. These microorganisms play a vital role in the global ecosystem as primary producers, utilizing sunlight and carbon dioxide to produce oxygen and organic compounds through photosynthesis. Because of this, they are considered key contributors to Earth's oxygen-rich atmosphere.
Cyanobacteria exhibit a wide array of morphological forms, ranging from unicellular to multicellular filamentous colonies. Some species can form specialized cells called heterocysts, which enable them to fix atmospheric nitrogen and convert it into a usable form for other organisms. This ability makes cyanobacteria important contributors to nitrogen cycling in ecosystems.
Although cyanobacteria are generally beneficial, under certain conditions, they can proliferate excessively, forming harmful algal blooms or cyanobacterial harmful algal blooms (cyanoHABs). These blooms can release toxins harmful to humans, animals, and aquatic life, posing risks to water quality and ecosystem health. Cyanobacteria and their toxins also have the potential to cause human health issues, including skin irritations, gastrointestinal problems, and respiratory distress.
Ongoing research on cyanobacteria aims to better understand their ecological roles, their adaptations to environmental conditions, and to develop strategies for managing and mitigating their harmful effects while harnessing their potential beneficial contributions to various sectors such as biotechnology and renewable energy
