Introduction
Archaea and the origin of life. The word Archaea originated from the Greeks, meaning beginning. Throughout this essay we will go through discovers of Archaea and why they are classified as Prokaryotes and what the actual evolutionary relationship of Archaea to Eukaryotes and bacteria. We will look at the differing views throughout the scientific community in regards to the number of domains. Over whether three domains of life or two domains of life fit in the Tree of life. We will look at some research that has supportive evidence of the same. This essay will then look at the Habitat of Archaea – why many Archaea are classified as extremophiles and how these are not just bacteria’s and that extremophiles are a diverse group and able to live in extreme conditions on earth. We will then talk about the Archaea and how they were originally classified as bacteria. Finally this essay will look at how Archaea work in symbiotic relationship in the digestive tract of termites.
Reasons that the Archaea have been classified as prokaryotes:
Before the latter part of the twentieth century Archaea was classified as an unusual group of bacteria called Archaeabacteria new research that pioneered the way by Dr Carl Woese and coworkers in the 1970’s which lead to work with phylogenetic on ribosomal RNA (rRNA) sequence comparisons using a technique that uses 16S rRNA sequencing. Moreover their information transfer systems or (DNA replication, transcription, translation) (Henderson’s, 1998).This is mainly involved in there active-protein translation, this helped accommodate Archaea to its own domain although they still have similar traits to their counterparts of Eukarya. Another different feature of Archaea is the distinctive method of...
... middle of paper ...
... E., Reid, W., Roterman, C., Sweeting, C., Thatje, S., & Zwirglmaier, K. (2012). The Discovery of New Deep-Sea Hydrothermal Vent Communities in the Southern Ocean and Implications for Biogeography PLoS Biology, 10 (1) DOI: 10.1371/journal.pbio.1001234
Lawrence, E (1998). Henderson’s Dictionary of Biological Terms, Eleventh Edition, Appendix 6,p.683
Syvanen, M. (2002). Rates of ribosomal RNA evolution are uniquely accelerated in eukaryotes. Journal of Molecular Evolution, 55(1), 85-91. doi:http://dx.doi.org/10.1007/s00239-001-2306-9
T. D. Brock, M. T. Madigan, J. M. Martinko, & J. Parker. 1994. Biology of Microorganisms, 7th ed. (New Jersey: Prentice Hall).
Yutin, N., Makarova, K. S., Mekhedov, S. L., Wolf, Y. I., & Koonin, E. V. (2008). The deep Archaea roots of eukaryotes. Molecular Biology and Evolution, 25(8), 1619-30. doi:http://dx.doi.org/10.1093/molbev/msn108
The eighteenth exercise of the laboratory manual titled Unknown Identification and Bergey’s Manual is an experiment to identify an unknown bacterium. In this exercise, a student must randomly choose a numbered bacterium available to the class. The keys in Appendix H, located on the last pages of the book, are the major helpful tools in this exercise because it provides completed steps of tests that needs to be performed in order to distinguish certain bacteria. This means that in this exercise, various types of tests and techniques must be performed to identify the chosen unknown bacterium. The unknown bacterium that I selected was number thirty-nine in which I discovered as the Bacillus megaterium after conducting several tests.
Just like bacteria, archaea are also single cell and are surrounded by a cell wall. Eukaryotes, unlike bacteria and archaea, contain a nucleus. And like bacteria and archaea, eukaryotes have a cell wall.
Todar, K. (2002). Streptococcus pyogenes (Vol. 1). Madison: University of Wisconsin-Madison Department of Bact. Retrieved July 30, 2008, from http://www.textbookofbacteriology.net/streptococcus.html
Miller, Kenneth R. and Joseph S. Levine. “Chapter 12: DNA and RNA.” Biology. Upper Saddle River: Pearson Education, Inc., 2002. Print.
Bacillus globigii. (n.d.) WordNet 3.0, Farlex clipart collection. (2003-2008). Retrieved March 20 2014 from http://www.thefreedictionary.com/Bacillus+globigii
Linking with the idea of hydrothermal vents being a 'reactor' for RNA hydrothermal vents rely on chemical energy from geothermal vents to sustain a organisms. Swarms of bacteria thrive in this environment which acts as an interface between the high temperature vents and cold oxygenated seawater. The bacteria thrive on gases produced by the vents such as methane and use these chemicals to produce simple organic molecules to support the local ecosystem in a similar way to plants using photosynthesis. Wachtershauser has proposed that a biochemical cycle grew and assembled the first living cell.
Linton, Alan. 1982. Microbes, Man and Animals: The Natural History of Microbial Interactions. John Wiley & Sons. 342pp
The Precambrian Era is when the Earth formed. Earth was barley a spec of dust in outer space and as time went by it gathered ice, rock and more dust particles. It eventually formed into a big rock flying around in space. The Earth was extremely hot and so when it rained the rain would evaporate in mid air or immediately after it hit the ground. But even though it evaporated these great rains cooled the Earth eventually building up water in lower areas creating oceans. The Earths atmosphere was water vapor, carbon dioxide, nitrogen and gases. After awhile oxygen level grew in the atmosphere. The earliest life forms were single celled organisms that lived in the oceans. These organisms used light energy to produce food called photosynthesis. These were called Prokaryotes and Eukaryotes. The evolution of multi celled organisms were Dramatic in change.
Talaro , K., & Chess, B. (2012). Foundations in microbiology. (8th ed., pp. 563-564). New York, NY:
The deep sea is one of the most hostile environments in the world, which a living organism is subjected to. As you progress from the surface (the epipelagic zone) through to the abyssopelagic zone near the basin of the ocean; the environmental characteristics begin to alter dramatically. Light, pressure, oxygen, temperature and food are abiotic factors that have all led to the fascinating adaptations of deep sea life. Pressure alone increases by 1 atmosphere for each 10m in depth which is an astonishing rate. The deep sea temperature remains between 2-4°c, which is just another factor inhabitants must overcome in order to survive, along with a reduced quantity and accessibility of essential factor’s like ;oxygen, food and light[3].
Cells are of two distinctly different types, prokaryotes and eukaryotes; thus, the living world is divided into two broad categories. The DNA of prokaryotes is a single molecule in direct contact with the cell cytoplasm, whereas the DNA of eukaryotes is much greater in amount and diversity and is contained within a nucleus separated from the cell cytoplasm by a membranous nuclear envelope. Many eukaryotic cells are further divided into compartments by internal membranes in addition to the nuclear envelope, whereas prokaryotic cells never contain completely
Figure 9. Bacterial elongation cycle. Elongation cycle involves sequential addition of amino acid to the growing peptide chain. Aminoacylated tRNA in complex with EF-Tu and GTP interacts with the A-site in the decoding center where the correctness of the codon-anticodon is determined. On accommodation aa-tRNA moves into the PTC after which the ribosome forms the hybrid A/P and P/E state in preparation of translocation. After GTP hydrolysis, dissociation of E-F-Tu-GDP and translocation, new aa-tRNA ternary complex reads the codon on the mRNA and continues this cycle(Voorhees e Ramakrishnan, 2013)
Levvit, Tom. "How Deep-sea Mining Could Destroy the." The Ecologist. N.p., 28 Oct. 2010. Web. 27 Mar. 2014. .
Leboffe, M. J., & Pierce, B. E. (2010). Microbiology: Laboratory Theory and Application, Third Edition 3rd Edition (3rd Ed.). Morton Publishing
Genomics- the classification of organisms based on their 16S rRNA (Wackett, Dodge, & Ellis, 2004; Xu, 2006)