Facts about Archaea

Archaea have no murein in their cell walls.

Archaea can reproduce using binary and multiple fission, fragmentation, and budding.

Archaea are similar to other prokaryotes in most aspects of cell structure and metabolism.

The relationship between Archaea and Eukarya remains an important problem.

Recently, several studies have shown that archaea exist not only in mesophilic and thermophilic (and hyperthermophic) environments but are also present, sometimes in high numbers, at low temperatures as well.

Many methanogenic archaea are found in the digestive tracts of animals such as ruminants, termites, and humans.

Archaea comes from the Greek ??????, meaning "ancient ones."

Recently, a species of flat, square archaean that lives in hypersaline pools has been discovered (Burns et al.

The enzymes isolated from some extremophile archaea have proven to be of great use in the biotechnology industry, able to function under conditions that would denature enzymes taken from most "normal" organisms.

Like bacteria and eukaryotes, archaea possess glycerol-based phospholipids.

Archaeans also have flagella that are notably different in composition and development from the superficially similar flagella of bacteria.

The name archaean has been used both for a single organism and as an adjective.

Archaea were originally described in extreme environments, but have since been found in many types of habitat.

Many archaeans are extremophiles (thrive in or require "extreme" conditions that would exceed optimal conditions for growth and reproduction in the majority of organisms).

The biological term, Archaea, should not be confused with the geologic phrase Archean eon, also known as the Archeozoic era.

Many archaeal tRNA and rRNA genes harbor unique archaeal introns, which are neither like eukaryotic introns, nor like bacterial (type I and type II) introns.

Perhaps even more significant are the large numbers of archaea found throughout most of the world's oceans, a predominantly cold environment (Giovannoni and Stingl 2005).

Woese argued that the bacteria, archaea, and eukaryotes each represent a primary line of descent that diverged early on from an ancestral progenote with poorly-developed genetic machinery.

Like bacteria, archaea are single-celled organisms lacking nuclei and are therefore prokaryotes.

Of note, the halobacteria can use light to produce ATP, although no archaea conduct photosynthesis with an electron transport chain, as occurs in other groups.

No clear examples of archaean pathogens are known (Eckburg 2003, Cavicchioli et al.

Several other characteristics also set the Archaea apart.

Archaeans also exhibit a variety of different types of metabolism.

Archaea are divided into two main taxonomic groups, the Euryarchaeota and Crenarchaeota, based on descent trees for ribosomal RNA.

Archaea are usually placed into three groups based on preferred habitat.

Archaea or Archaebacteria is a major division of living organisms, as well as the name of the members of this group, which in singular form are known as archaeon, archaeum, or archaean.