The ArchaeansThe ArchaeansLaura RodriguezLaura RodriguezMicrobiology B235Microbiology B235

CRN# 10582CRN# 10582

February 19, 2007February 19, 2007

The Dead SeaThe Dead Sea

Deep Sea VentsDeep Sea Vents

YellowstoneYellowstone

Essential QuestionsEssential Questions

1. What are the Archaea?1. What are the Archaea?

2. What makes them 2. What makes them different from bacteria different from bacteria and eukaryotes? and eukaryotes?

3. Where are Archaea 3. Where are Archaea found?found?

4. What are some special 4. What are some special ArchaeansArchaeans

MethanopyrusCourtesy Karl Stetter

Discovery of the ArchaeaDiscovery of the Archaea

Dr. Carl Woese was studying DNA Dr. Carl Woese was studying DNA sequences to determine relationships sequences to determine relationships among prokaryotes in the late 1970’s . among prokaryotes in the late 1970’s .

He found 2 distinct groups. Those He found 2 distinct groups. Those prokaryotes living in extreme conditions prokaryotes living in extreme conditions were very different from the usual bacteria were very different from the usual bacteria and also from eukaryotes and also from eukaryotes

He came up with 3 domains: He came up with 3 domains: Archaea Archaea Bacteria Bacteria EukaryotaEukaryota

Archaea GroupsArchaea Groups

The Archaeans The Archaeans have been have been divided into 3 divided into 3 groupsgroups

EuryarcheotaEuryarcheota methane producers, methane producers, salt loverssalt lovers

CrenarcheotaCrenarcheota extreme extreme temperaturestemperatures

KorarcheotaKorarcheota recently discovered, recently discovered,

based on DNA based on DNA sequencessequences

Sub groups of ArchaeansSub groups of Archaeans

Methanogens Methanogens - produce methane - produce methane gas as a waste product.gas as a waste product.

Halophiles - Halophiles - live in salty live in salty environments.environments.

Thermophiles - Thermophiles - live at extremely live at extremely hot temperatures.hot temperatures.

Sychrophiles - Sychrophiles - live at unusually cold live at unusually cold temperatures. temperatures.

MorphologyMorphologyVery small – less than 1 micronVery small – less than 1 micronMany shapes – coccus, bacillus, triangular, squareMany shapes – coccus, bacillus, triangular, squareMay have 1 or more flagellaMay have 1 or more flagellaNo internal membranesNo internal membranesDNA in a single loop – plasmidDNA in a single loop – plasmidtRNA different from all other life formstRNA different from all other life formsSome characteristics of tRNA more similar to Some characteristics of tRNA more similar to eukaryotes than to bacteriaeukaryotes than to bacteriaRibosomes also more like eukaryotes than Ribosomes also more like eukaryotes than bacteriabacteriaRNA sequences different from bacteria and RNA sequences different from bacteria and eukaryoteseukaryotes

Archaeans are structurally similar Archaeans are structurally similar to bacteria but chemically to bacteria but chemically

differentdifferent Cell Wall is not made of peptidoglycan, chitin or Cell Wall is not made of peptidoglycan, chitin or

cellulose, but is chemically distinct cellulose, but is chemically distinct (pseudomurein)(pseudomurein)

Cell Membrane also very different chemicallyCell Membrane also very different chemically chirality of glycerol: Archaeans have L glycerol instead chirality of glycerol: Archaeans have L glycerol instead

of Dof D ether linkage instead of an ester linkage –Archaean ether linkage instead of an ester linkage –Archaean

linkage lacks an oxygen atom and gives membrane linkage lacks an oxygen atom and gives membrane different chemical propertiesdifferent chemical properties

isoprenoid chains instead of fatty acid side chainsisoprenoid chains instead of fatty acid side chains branching of side chains. This does not occur in bacteria branching of side chains. This does not occur in bacteria

or eukaryotes Archaeans can form transmembrane or eukaryotes Archaeans can form transmembrane phospholipids and carbon rings. This may contribute to phospholipids and carbon rings. This may contribute to membrane stability at high temperaturesmembrane stability at high temperatures

Fossil RecordFossil Record Difficult to find fossils of such small Difficult to find fossils of such small

organisms. Physically would look the same organisms. Physically would look the same as bacteria.as bacteria.

Need to look for molecular fossils – Need to look for molecular fossils – chemicals that are unique to the organism chemicals that are unique to the organism that do not decay or decay into predictable that do not decay or decay into predictable and known secondary chemicalsand known secondary chemicals

Isoprenes are such molecular fossils of Isoprenes are such molecular fossils of archaeans. They have been found in the archaeans. They have been found in the Isua district of Western Greenland which Isua district of Western Greenland which contains the oldest sediments known – 3.8 contains the oldest sediments known – 3.8 billion years oldbillion years old

Archaeans as earliest lifeArchaeans as earliest life

Archaeans were on earth within 1 Archaeans were on earth within 1 billion years of Earth forming. billion years of Earth forming.

Earth was still very hot, lots of Earth was still very hot, lots of methane and ammonia.methane and ammonia.

Toxic for life today, but just right for Toxic for life today, but just right for archaeans.archaeans.

Location, Location, LocationLocation, Location, Location Extreme environments Extreme environments

Deep sea hydrothermal ventsDeep sea hydrothermal vents Hot springsHot springs Hypersaline watersHypersaline waters Extremely alkaline or acidic Extremely alkaline or acidic

environmentsenvironments Digestive tracts of termites, Digestive tracts of termites,

cows and marine lifecows and marine life Anoxic muds of marshesAnoxic muds of marshes Petroleum depositsPetroleum deposits Ocean bottomOcean bottom Open ocean in planktonOpen ocean in plankton

MethanothermusCourtesy Karl Stetter

HalobacteriumHalobacterium One of the most studied One of the most studied

ArchaeansArchaeans Salt loving – found in salt ponds Salt loving – found in salt ponds

at SE end of San Francisco Bay, at SE end of San Francisco Bay, Dead SeaDead Sea

Contains bacteriorhodopsin, Contains bacteriorhodopsin, light-sensitive pigment that light-sensitive pigment that gives gives HalobacteriumHalobacterium its color its color

This is a simple photosynthetic This is a simple photosynthetic pigment similar to rhoodopsin pigment similar to rhoodopsin found in vertebrate retina found in vertebrate retina

Found to withstand lethal doses Found to withstand lethal doses of UV radiation, extreme of UV radiation, extreme dryness and eve the vacuum of dryness and eve the vacuum of spacespace

Salt flats at Lake Magadi, Kenya. The flats are red due to the proliferation of Halobacteria.

Pyrolobus fumariiPyrolobus fumarii

Literally, “fire lobe of the Literally, “fire lobe of the chimney”chimney”

Found at the deep sea vents Found at the deep sea vents in “black smokers”in “black smokers”

Increased the accepted Increased the accepted upper temperature limit for upper temperature limit for life to 113 degrees Celsius life to 113 degrees Celsius (235.4 degrees Fahrenheit).(235.4 degrees Fahrenheit).

Pyrolobus fumarii-Zellen, EM-Aufnahme - Image courtesy H. Huber, M. Hohn, R. Rachel & K.O. Stetter, Univ. Regensburg, Germany

Pyrococcus furiosisPyrococcus furiosis Live near deep sea ventsLive near deep sea vents Produce fuel, hydrogen Produce fuel, hydrogen

gasgas Produces an extra-stable Produces an extra-stable

enzyme that isn’t enzyme that isn’t denatured as it goes denatured as it goes through many cycles in through many cycles in the process of the process of polymerase chain polymerase chain reaction,reaction,PCRPCR. This is the . This is the method that is used for method that is used for gene sequencing and gene sequencing and DNA fingerprinting.DNA fingerprinting.

Courtesy of K.O. Stetter and R. Rachel, University of Regensburg.

Archaeoglobus fulgidusArchaeoglobus fulgidus Anaerobes Anaerobes Hyperthermophilic Hyperthermophilic Marine sulphate reducers Marine sulphate reducers Found in hydrothermal Found in hydrothermal

environments environments Contributes to Contributes to

subsurface oil-well subsurface oil-well 'souring' by iron 'souring' by iron sulphide, sulphide,

Causes corrosion of iron Causes corrosion of iron and steel in oil-and gas-and steel in oil-and gas-processing systems. processing systems.

Courtesy Karl Stetter Courtesy Karl Stetter

"Archaea and other extremists." "Archaea and other extremists." Microbe WorldMicrobe World. 2006. American Society for Microbiology . 14 Feb 2007 . 2006. American Society for Microbiology . 14 Feb 2007 <http://www.microbeworld.org/microbes/archaea/>. <http://www.microbeworld.org/microbes/archaea/>.

"Archaeoglobus fulgidus ." "Archaeoglobus fulgidus ." TIGRTIGR. 2007. The Institute for Genomic Research. 18 Feb 2007 . 2007. The Institute for Genomic Research. 18 Feb 2007 <http://www.tigr.org/tdb/CMR/gaf/htmls/Background.html>. <http://www.tigr.org/tdb/CMR/gaf/htmls/Background.html>.

Barry, Patrick l.. "Secrets of a salty survivor." Barry, Patrick l.. "Secrets of a salty survivor." Science @ NASA Science @ NASA . September 9, 2004 . NASA. 12 Feb 2007 . September 9, 2004 . NASA. 12 Feb 2007 <http://science.nasa.gov/headlines/y2004/10sep_radmicrobe.htm>. <http://science.nasa.gov/headlines/y2004/10sep_radmicrobe.htm>.

Beal, Heather. "Microbial Life in Extremely Hot Environments." Beal, Heather. "Microbial Life in Extremely Hot Environments." Microbial Life Education ResourcesMicrobial Life Education Resources. November 30. . November 30. 2006 . SERC. 14 Feb 2007 <http://serc.carleton.edu/microbelife/extreme/extremeheat/index.html>. 2006 . SERC. 14 Feb 2007 <http://serc.carleton.edu/microbelife/extreme/extremeheat/index.html>.

Blöchl, Elisabeth, Reinhard Rachel, Siegfried Burggraf, Doris Hafenbradl, Holger W. Jannasch, and Karl O. Stetter . Blöchl, Elisabeth, Reinhard Rachel, Siegfried Burggraf, Doris Hafenbradl, Holger W. Jannasch, and Karl O. Stetter . "Pyrolobus fumarii, gen. and sp. nov., represents a novel group of archaea, extending the upper temperature limit for "Pyrolobus fumarii, gen. and sp. nov., represents a novel group of archaea, extending the upper temperature limit for life to 113°C ." life to 113°C ." Extremophiles JournalExtremophiles Journal Vol 1 issue 1February 19, 2004 14-21. February 18, 2007 Vol 1 issue 1February 19, 2004 14-21. February 18, 2007 <http://www.springerlink.com/content/g5tdkx307y56g0n0/>. <http://www.springerlink.com/content/g5tdkx307y56g0n0/>.

"Diversa Completes of Sequencing of Pyrolobus fumarii Genome - the World's Highest Temperature Organism ." "Diversa Completes of Sequencing of Pyrolobus fumarii Genome - the World's Highest Temperature Organism ." SpaceRef Interactive IncSpaceRef Interactive Inc. September 25,2001 . Diversa. 18 Feb 2007 <http://www.spaceref.com/news/viewpr.html?. September 25,2001 . Diversa. 18 Feb 2007 <http://www.spaceref.com/news/viewpr.html?pid=6101>. pid=6101>.

"First salt-loving bug sequenced ." "First salt-loving bug sequenced ." BBC News BBC News 2 October, 2000 February 10, 2007 2 October, 2000 February 10, 2007 <http://news.bbc.co.uk/2/hi/sci/tech/953356.stm>. <http://news.bbc.co.uk/2/hi/sci/tech/953356.stm>.

Tortora, Gerard, Berdell Funke, and Christine Case. Microbiology:An Introduction. 9th. San Francisco: Pearson Tortora, Gerard, Berdell Funke, and Christine Case. Microbiology:An Introduction. 9th. San Francisco: Pearson Education, Inc, 2007.Education, Inc, 2007.

Waggoner, Ben, and Brian Speer. ", Introduction to the Archaea: Life's extremists ." Waggoner, Ben, and Brian Speer. ", Introduction to the Archaea: Life's extremists ." University of California University of California Museum of PaleontologyMuseum of Paleontology. 1994-2007. University of California Museum of Paleontology. 10 Feb 2007 <, . 1994-2007. University of California Museum of Paleontology. 10 Feb 2007 <, http://www.ucmp.berkeley.edu/archaea/archaea.html>. http://www.ucmp.berkeley.edu/archaea/archaea.html>.

Zaun, Harald. "Von irdischen und außerirdischen Überlebenskünstlern." Zaun, Harald. "Von irdischen und außerirdischen Überlebenskünstlern." Mikrobiologe und Astrobiologie Mikrobiologe und Astrobiologie . August . August 23,2003. Heise Zeitschriften Verlag . 18 Feb 2007 <http://www.heise.de/tp/r4/artikel/15/15412/1.html>. 23,2003. Heise Zeitschriften Verlag . 18 Feb 2007 <http://www.heise.de/tp/r4/artikel/15/15412/1.html>.

CreditsCredits