Kingdom Archaea
Representative Organisms: Methanothermus, Archaeoglobus
Cell Type: • Prokaryotic (NO nucleus)
• unicellular
Cell Structure:
• cell membrane of archaea is different from that of bacteria in that they contain
unusual lipids.
• these lipids remain stable at extreme high and low temperatures. • similar shapes to bacteria
Methods of Reproduction:
Reproduction in archaea is asexual using the process of binary fission. Some archaea use conjugation Biological Role:
• Some Archae produce methane Connection to Human Health:
• None (this type of organism is rarely in contact with humans) 1
Kingdom Archaea
Types of Archaea:
• methanogens: are anaerobes, live in the depths of swamps and sewage and
the digestive tract of animals, give off methane (CH4)
• halophiles: love salty environments • thermoacidophiles: love heat and acid • psychrophiles: those that live at unusually cold temperatures
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Kingdom Archaea
Characteristics:
Archaea were initially classified as bacteria. But biochemically, and genetically, they are very different from bacteria. (thought to evolve from a common ancestor)
Archaea live in extreme environments (i.e. 100 oC). Extremophiles
Archaea obtains energy from inorganic molecules or light.
Archaeans obtain their energy from inorganic molecules such as
• hydrogen gas, • carbon dioxide • sulfur. Archaea are similar to other prokaryotes in most aspects of cell structure and metabolism. However, their genetic transcription and translation ­ the two central processes in molecular biology ­ do not show many typical bacterial features, and are in many aspects similar to those of eukaryotes. 3
Archaea and Biotechnology
Unique enzymes allow these organisms to live under extreme conditions of heat, cold, acidity, and salinity. A Biotechnology technique called the Polymerase Chain Reaction (PCR) uses an enzyme from an archaeon species that can grow in temperatures greater than 70o C. Because the process involves a technique that heats the reactants, thus the enzyme can be reused and are not destroyed in the process. PCR is an important technique used to make copies of DNA and can be used in forensic science and biotechnology
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Comparing Bacteria and Archaea
Bacteria
Archaea
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