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Edward I. Stiefel 1942-2006 professor, Princeton Univ. senior scientific advisor, Exxon Corporate Research (ExxonMobil) Nucleosynthesis: Stars and Nova Explosions Produce Iron Iron has the highest binding energy per nucleon. Iron is a relatively abundant element in the cosmos. Seawater Crust [Mo6+] = 10-7 M [Fe] = 56g/1 kg [Fe3+] = 10-17 M [Mo] = 0.001g/1 kg [W] = 0.001g/1 kg ___) and Molybdenum (------) ___ Iron (Molybdenum in the Oceans over Time (-----) and Iron ( ) in the Oceans Over Ti me Archean 1850-1250 Ma Phanerozoic [Fe] < [Mo] [Mo] < [Fe] [Mo] < [Fe] [Fe] < [Mo] Concentration Anbar and Knoll, Science (2002) Evolution of Life on Earth Lawler (2001) Storage and yearly changes (fluxes) of the carbon between the atmosphere, water and the Earth. Quantities are expressed in billion tonnes of carbon. Redrawn from NASA's Earth Observatory. ‘Biological Pump’ Leads to Burial of Some Organic Carbon Chisholm (2002) ExxonMobile patent for using methanogens Methanotrophic Bacteria: Use in Bioremediation R. L. Brigmon Westinghouse Savannah River Company Aiken, SC 29808 More Complete Nitrogen Cycle Ammonia monooxygenase O2 Nitrification NO2- NH2 OH Nitrogen Fixation NO3- N2 NH3 Denitrification N2O reductase N2 O NO NO2- NO2Nitrate Assimilation Reduced Nitrite reductace Oxidized = Copper Enzymes More Complete Nitrogen Cycle Nitrite oxidoreductase O2 Nitrification NO2- NH2 OH Nitrogen Fixation NO3- N2 NH3 Denitrification Nitrogenase N2 O NO Respiratory Nitrate Reductase NO2Assimilatory Nitrate Reductase NO2Nitrate Assimilation Reduced Oxidized = Molybdenum Enzyme Haber Process for Ammonia Synthesis (Nitrogen Fixation) Human Population Growth Figure 4. The cyanobacterium Anabaena. The organism lives as a multicellular filament or chain of cells. The predominant photosynthetic (bright yellow-green) cells conduct photosynthesis, while the obviously large "empty" cells occasionally seen along a filament are differentiated cells in which nitrogen fixation, but not photosynthesis, takes place. photosynthesis N2 Inorganic Sulfur Cycle Molybdate Inhibition - O PPi ATP O A O O SO4 O- P S O O O- 2ATP sulfurylase APS HO Sulfite Oxidase A PS reductase OH ATP APS phosphorylase ADP SO3 2- PAPS reductase PAPS Sulfite reductase H2 S, HS Tetrathionate Reductase S4O 62- S2O 32- - Polysulfide reductase Sn2- S8 ScienceDaily (Oct. 5, 2007) — Thousands of new kinds of marine microbes have been discovered at two deep-sea hydrothermal vents off the Oregon coast by scientists at the MBL (Marine Biological Laboratory) and University of Washington's Joint Institute for the Study of Atmosphere and Ocean. Their findings, published in the journal Science, are the result of the most comprehensive, comparative study to date of deep-sea microbial communities that are responsible for cycling carbon, nitrogen, and sulfur to help keep Earth habitable. The researchers discovered that while there may be as few as 3,000 different kinds of archaea at these sites, the bacteria exceed 37,000 different kinds. "Most of these bacteria had never been reported before, and hundreds were so different from known microbes that we could only identify them to the level of phylum," says lead author, Julie Huber of the MBL. Opalescent Pool in Yellowstone National Park, Wyoming USA. In these types of hot springs, the orange, yellow and brown colors are due to pigmented photosynthetic bacteria which make up the microbial mats. The mats are literally teeming with bacteria. Cross section of a microbial mat showing the different layers of pigmented bacteria. (in cm.) Algen zijn belangrijke producenten van Dimethylsulfide (DMS). DMS is een vluchtig gas dat en grote rol speelt bij het ontstaan van nevel en wolken. Dit principe geldt voornamelijk in het Zuidelijk halfrond. In het Noordelijk halfrond is er te veel industriële uitstoot die het omzettingsproces van DMS in nevel beïnvloedt. Research @: www.rug.nl/boom/onderwerpen/klimaat/ijsalgen Symbiosis, or the living together of different organisms, allows some species to live in otherwise hostile environments, so it can be a powerful mechanism of evolutionary change. This is especially true in the deep sea. Survival in some deep-sea environments requires capabilities that animals alone don't possess. So teaming up with a microbial partner is the secret of survival for many host animals living in such environments. Dr Goffredi says: "Measures of significant population sizes, and the discovery of four additional host species in only three years, suggests that the Osedax worms and their bacterial 'partners' are likely to play substantial roles in the cycling of nutrients into the surrounding deep-sea community." This can be put into context by considering that the Osedax worms and their symbiotic bacteria can turn-over a large amount of organic carbon (one whale carcass may weigh up to 50 tons), approximately 2000 years faster than the usual mechanism of carbon deposition to the deep seafloor.