Notes on Archaea | I love my lavie <3

Domain Archaea

A domain of single-celled microorganisms that are prokaryotes and possess unique characteristics different from bacteria and eukarya.

Phylogenetic analysis

A method used to study the evolutionary relationships between organisms based on their genetic sequences.

Aboriginal lines of descent

Refers to the three main branches of living systems identified in the study - eubacteria, archaebacteria, and urkaryotes.

Archaea

Prokaryotic microorganisms that are phylogenetically closer to eukarya and possess characteristics similar to both bacteria and eukarya.

Plaque

A commemorative plaque that honors Carl Woese's contribution to the field of molecular sequencing and cataloging of 16S rRNA.

Cellular organization

Archaea have a simple cellular organization with a single bounding membrane.

Lipids

Archaeal membranes are made of lipids comprised of isoprenoid chains ether-linked to a glycerol backbone.

Cell wall

Archaea do not have peptidoglycan in their cell walls. Instead, they have pseudomurein or methanochondroitin.

S-layer

A paracrystalline surface layer found in archaea that provides resistance to osmotic lysis, high temperature, and low pH.

Genome organization

Archaea likely have small circular genomes, and their genes are often grouped by function for coordinated transcription.

Cytoskeleton

Archaea have cytoskeletal filaments similar to those found in bacteria and eukaryotes, and they play a role in cell shape and division.

Cell division

Archaea undergo cell division similar to bacteria, including the formation of a constriction ring to separate cells.

Structural and functional characteristics

Archaea possess unique characteristics compared to bacteria and eukarya, including differences in cell type, morphology, cell wall composition, plasma membrane type, and more.

Phylogenetic diversity

Archaea are diverse and present in all environments, with different groups such as crenarchaeota, euryarchaeota, and the recently discovered Asgard supergroup.

Extremophiles

Archaea are known for their ability to thrive in extreme environments, such as high temperatures, extreme pH levels, and high salinity.

Eukaryogenesis

The evolutionary process that gave rise to eukaryotic cells, proposed to involve an archaeon engulfing a bacterium and merging into a single bioentity.

Endosymbiotic theory

The theory that explains the origin of mitochondria and chloroplasts in eukaryotic cells through the engulfment of bacteria by ancestral eukaryotes.

Candidatus Prometheoarchaeum syntrophicum

An anaerobic archaeon isolated from deep-sea methane seep sediment, related to the Lokiarchaeota and potentially important in understanding eukaryogenesis.

Importance of Archaea

Archaea play ecological roles in element recycling, have potential applications in health and medicine, food and industry, and are a subject of ongoing research.

Extremozymes

Enzymes produced by archaea that can withstand extreme conditions and have industrial applications in various fields.