Oceans bacteria

Sieburth, J. McN., Distribution and Activity of Oceanic Bacteria, Deep-... 

Several fatty acids, specifically 15 0, 17 0 and all branched fatty acids, are produced primarily by both aerobic and anaerobic bacteria [55-57] and the sum of those fatty acids has been used to estimate bacterial contributions [58-61]. A comparison of bacterial markers in plankton, sediment trap and sediment samples showed the lowest values, with little variation, in plankton samples (Fig. 3 b), and the greatest bacterial levels in sediments. The sediment traps, containing partially degraded material, had bacterial marker levels intermediate between the other two sample types, and levels of bacterial markers increased with increasing period of deployment. However, there are conflicting theories concerning the usefulness of these markers and, for that reason, bacterial markers should only be employed with caution. For instance, in a recent paper, Harvey and Macko [57] did not find a correlation between total fatty acids attributed to bacteria and bacterial carbon, and they suggest that bacterial fatty acids only be used as qualitative tools to estimate bacterial contributions. Wakeham [62] also points out that fatty acids of common oceanic bacteria may not be compositionally different from planktonic fatty acids so that bacterial... 

Bubbles form in nature in many different ways. If a molecule has a pattern of water-loving and water-avoiding parts, it can form a bubble. Bubbly sea foam is made of proteins and sugars from the life in the sea. Ocean bacteria communicate and transfer material by blowing water-filled vesicle bubbles. 

Other appHcations of firefly hioluminescence include measurement of the activity of bacteria in secondary sewage treatment activated sludge (296,297), detection of bacteria in clean rooms and operating rooms, measurement of bacteria in bottled foods, beverages (298), and pharmaceuticals (299), determination of the antimicrobial activity of potential dmgs (300), determination of the viabiHty of seeds (301), and measuring marine biomass concentrations as a function of ocean depth or geographical location (302). 

Since methane is almost always a byproduct of organic decay, it is not surprising that vast potential reserves of methane have been found trapped in ocean floor sediments. Methane forms continually by tiny bacteria breaking down the remains of sea life. In the early 197Qs it was discovered that this methane can dissolve under the enormous pressure and cold temperatures found at the ocean bottom. It becomes locked in a cage of water molecules to form a methane hydrate (methane weakly combined chemically with water). This "stored" methane is a resource often extending hundreds of meters down from the sea floor. 

The most important type of mixed solution is a buffer, a solution in which the pH resists change when small amounts of strong acids or bases are added. Buffers are used to calibrate pH meters, to culture bacteria, and to control the pH of solutions in which chemical reactions are taking place. They are also administered intravenously to hospital patients. Human blood plasma is buffered to pH = 7.4 the ocean is buffered to about pH = 8.4 by a complex buffering process that depends on the presence of hydrogen carbonates and silicates. A buffer consists of an aqueous solution of a weak acid and its conjugate base supplied as a salt, or a weak base and its conjugate acid supplied as a salt. Examples are a solution of acetic acid and sodium acetate and a solution of ammonia and ammonium chloride. 

Rathgeber C, N Yurkova, E Stackebrandt, JT Beatty, V Yurkov (2002) Isolation of tellurite and selenite-resistant bacteria from hydrothermal vents of the Juan de Fuca Ridge in the Pacific Ocean. Appl Environ Microbiol 68 4613-4622. 

Interest in the possible persistence of aliphatic sulfides has arisen since they are produced in marine anaerobic sediments, and dimethylsulfide may be implicated in climate alteration (Charlson et al. 1987). Dimethylsnlfoniopropionate is produced by marine algae as an osmolyte, and has aronsed attention for several reasons. It can be the source of climatically active dimethylsulfide (Yoch 2002), so the role of specific bacteria has been considered in limiting its flux from the ocean and deflecting the prodncts of its transformation into the microbial sulfur cycle (Howard et al. 2006). 

By far the most important ores of iron come from Precambrian banded iron formations (BIF), which are essentially chemical sediments of alternating siliceous and iron-rich bands. The most notable occurrences are those at Hamersley in Australia, Lake Superior in USA and Canada, Transvaal in South Africa, and Bihar and Karnataka in India. The important manganese deposits of the world are associated with sedimentary deposits the manganese nodules on the ocean floor are also chemically precipitated from solutions. Phosphorites, the main source of phosphates, are special types of sedimentary deposits formed under marine conditions. Bedded iron sulfide deposits are formed by sulfate reducing bacteria in sedimentary environments. Similarly uranium-vanadium in sandstone-type uranium deposits and stratiform lead and zinc concentrations associated with carbonate rocks owe their origin to syngenetic chemical precipitation. 

In the same year, Miller and the biologist Antonio Lazcano (National Autonomous University of Mexico) spoke out against hypotheses that life could have originated at hydrothermal vents. They believe that the presence of thermophilic bacteria (the oldest life forms) does not prove that biogenesis occurred in the depths of the oceans. Stanley Miller sees a greater chance for successful pre-biotic chemistry under the conditions of a cold primeval Earth rather than at high temperatures in hydrothermal regions (Miller and Lazcano, 1995). 

Many unicellular eukaryotes are free-living cells, but may form huge local communities, which are especially beneficial to the homeostasis of the ocean/atmos-phere carbon cycle, e.g. coccoliths. Many others are not free-living, but are extremely valuable in symbiotic relationship with multi-cellular plants and animals. Unfortunately, some unicellular eukaryotes are the causes of disease, for example Trypanosoma, which are animals and cause sleeping sickness in humans (see Section 8.9 for parallel diseases of plants). These facts are reminders that while we consider that the whole ecosystem works to one general purpose (Section 4.4), this does not exclude the obvious feature that within its overall associations we can see diseases inflicted on one species by another or competition between similar species. Many bacteria are also causes of serious eukaryote diseases. Even so at the end of... 

The pK of Ca2+aq (204), 12.6 at zero ionic strength, rising to over 13 as ionic strength increases, means that concentrations of CaOH+aq will be negligible in body fluids (lpolluted waters, and under all conditions of biological relevance, from the very low pHs of 0.5 (Thiobacillus thiooxidans) to 1.5 at which bacteria used for oxidative metal extraction operate (205), through acid soils and acid rain (pH 3 to 6), streams, rivers, and oceans (pH 6 to 8), soda lakes (pH 10), up to the pHs of 11 or more in Jamaican Red Mud slurry ponds (206) (cf. Section II.C.l below). 

Simply on the basis of the normal composition of marine organisms, we would expect proteins and peptides to be normal constituents of the dissolved organic carbon in seawater. While free amino acids might be expected as products of enzymic hydrolysis of proteins, the rapid uptake of these compounds by bacteria would lead us to expect that free amino acids would normally constitute a minor part of the dissolved organic pool. This is precisely what we do find the concentration of free amino acids seldom exceeds 150 xg/l in the open ocean. It would be expected that the concentration of combined amino acids would be many times as great. There have been relatively few measurements of proteins and peptides, and most of the measurements were obtained by measuring the free amino acids before and after a hydrolysis step. Representative methods of this type have been described [245-259]. Since these methods are basically free amino acid methods, they will be discussed next in conjunction with those methods. 

Dimethyl sulfide is derived primarily from the enzymatic hydrolysis of dimethylsulfoniopropionate(CH3)2S+CH2CH2COO DMSP),an osmoregulatory compound produced by a wide variety of marine phytoplankton [313,317]. Intracellular DMSP hydrolysis has been shown in phytoplankton [318], in macro algae [319], and also in bacteria following uptake of DMSP from seawater [320]. Reported seawater concentrations of dissolved dimethyl sulfide (< 0.1-90 nM) and DMSP (1 -1000 nM) vary with increasing depth, spatially from coastal areas to the open ocean, and also temporally from winter to summer [313-316]. 

For most people, BL is represented by the flash of the firefly or the phosphorescence that frequently occurs on agitating the surface of ocean water. Chemical excitation, luminescent reactions occurs in almost all zoological kingdoms (bacteria, dinoflagelates, Crustacea, worms, clams, insects, and fishes) except higher vertebrates BL is not found in any organisms higher than fish. In most cases this phenomenon occurs within specialized cells called photocytes [3-5], As shown in Table 1, BL occurs in many terrestrial forms but is most common in the sea, particularly in the deep ocean, where the majority of species are luminescent [6],... 

In addition to the dissolved elements and compounds in the oceanic water column, a wide variety of water column chemicals are found in marine organisms and organic detritus. For example, a milliliter of surface seawater can contain on the order of 10 million viruses, 1 million bacteria, 100,000 phytoplankton, and 10,000 zooplankton [9]. With the advent of soft ionization processes for mass spectrometry systems, scientists have been able to study these marine organisms at molecular level. The use of electrospray ionization (ESI see Section 2.1.15), atmospheric pressure chemical ionization... 

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