Methanococci It is the plural of methanococcus. Methanococcus is a genus of coccoid methanogens of the family Methanococcaceae. They are all mesophiles, except the thermophilic M. thermolithotrophicus and the hyperthermophilic M. jannaschii. The latter was discovered at the base of a “white smoker” chimney at 21°N on the East Pacific Rise and it was the first archaeal genome… Read More »


Methanobacterium In taxonomy, Methanobacterium is a genus of the Methanobacteriaceae. Contrary to their name, they are not exactly a bacterial species as they belong to the archaea and have the distinguishing biopolymer, peptidoglycan, missing from their cell membranes. Methanobacterium are nonmotile and live without oxygen. Some members of this genus can use formate to reduce methane; others live… Read More »

Lysinibacillus fusiformis

Lysinibacillus fusiformis Introduction: Lysinibacillus fusiformis (commonly abbreviated L. fusiformis) is a gram-positive, rod-shaped bacterium of the genus Lysinibacillus. Scientists have yet to completely characterize this microbe’s pathogenic nature. Though little is known about this organism, several genome sequencing projects for various strains of L. fusiformis are currently underway. History: Lysinibacillus fusiformis was initially isolated from the surface of… Read More »

Kingdom Plantae

Kingdom Plantae: Plants are mainly multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, plants were treated as one of two kingdoms including all living things that were not animals, and all algae and fungi were treated as plants. However, all current definitions of Plantae exclude the fungi and some algae, as well as the prokaryotes (the archaea… Read More »

Geobacillus stearothermophilus

Cell structure Geobacillus stearothermophilus (previously Bacillus stearothermophilus)[1][2] is a rod-shaped, Gram-positive bacterium and a member of the division Firmicutes. Ecology The bacterium is a thermophile and is widely distributed in soil, hot springs, ocean sediment, and is a cause of spoilage in food products. It will grow within a temperature range of 30 to 75°C. Some strains are… Read More »


Excavata Excavata is a large and diverse grouping that has been proposed based on a synthesis of morphological and molecular data. Many excavates share a similar feeding groove structure (from which the name is derived) (Simpson and Patterson, 2001; Simpson and Patterson, 1999). Many others lack this structure, but are demonstrably related to lineages that possess it in… Read More »

Cell wall

Cell wall The cells of plants and algae, fungi and most chromalveolates have a cell wall, a layer outside the cell membrane, providing the cell with structural support, protection, and a filtering mechanism. The cell wall also prevents over-expansion when water enters the cell. The major polysaccharides making up the primary cell wall of land plants are cellulose, hemicellulose, and pectin. The cellulose microfibrils are linked via hemicellulosic tethers to… Read More »

Centromeres and Telomeres:

Centromeres and Telomeres: Centromeres and telomeres are two essential features of all eukaryotic chromosomes. Each provide a unique function that is absolutely necessary for the stability of the chromosome. Centromeres are required for the segregation of the centromere during me iosis and mitosis, and teleomeres provide terminal stability to the chromosome and ensure its survival. Centromeres are those condensed… Read More »

Prokaryotic and eukaryotic cells

What are the key features of eukaryotic cells? Unlike prokaryotic cells, eukaryotic cells have: A membrane-bound nucleus, a central cavity surrounded by membrane that houses the cell’s genetic material. A number of membrane-bound organelles, compartments with specialized functions that float in the cytosol. (Organelle means “little organ,” and this name reflects that the organelles, like the organs of our body, have unique… Read More »

Role of Endosymbiosis in Eukaryotic Evolution

In addition to providing a significant nutritional mode, the advent of endocytosis in an ancestor of living eukaryotes also enabled a completely new way to generate cellular change and complexity: endosymbiosis. Put simply, endosymbiosis is the process by which one cell is taken up by another and retained internally, such that the two cells live together and integrate… Read More »