Autotrophe

By changing the enzyme and mediator, the amperometric sensor in Figure 11.39 is easily extended to the analysis of other substrates. Other bioselective materials may be incorporated into amperometric sensors. For example, a CO2 sensor has been developed using an amperometric O2 sensor with a two-layer membrane, one of which contains an immobilized preparation of autotrophic bacteria. As CO2 diffuses through the membranes, it is converted to O2 by the bacteria, increasing the concentration of O2 at the Pt cathode. 

Chlorella pyrenoidosa 200-m ponds outdoor sunlight, continuous CO2, urea autotrophic or mixotrophic with acetate 6.0-7.0 19.0-30.5 34... 

Nitrate and Nitrite. Nitrate is usually present in trace quantities in surface waters but occasionally occurs in high concentrations in some groundwaters. If present in excessive amounts, it can contribute to the illness infant methemoglobinemia. Nitrate is an essential nutrient for many photosynthetic autotrophs. Nitrite is an intermediate in the reduction of nitrate as well as in the oxidation of ammonia it is also used as a corrosion inhibitor in some industrial processes. 

Autotroph Organism which uses carbon dioxide as the sole carbon source. Autotrophic nitrification Oxidation of ammonium to nitrate through the combined... 

As we began this chapter, we saw that photosynthesis traditionally is equated with the process of COg fixation, that is, the net synthesis of carbohydrate from COg. Indeed, the capacity to perform net accumulation of carbohydrate from COg distinguishes the phototrophic (and autotrophic) organisms from het-erotrophs. Although animals possess enzymes capable of linking COg to organic acceptors, they cannot achieve a net accumulation of organic material by these reactions. For example, fatty acid biosynthesis is primed by covalent attachment of COg to acetyl-CoA to form malonyl-CoA (Chapter 25). Nevertheless, this fixed COg is liberated in the very next reaction, so no net COg incorporation occurs. 

Butlin, K. R. and Postgate, J. R., in Autotrophic Micro-organisms , Symp. Soc. Gen. Microbiol., Cambridge University Press (1954)... 

Blue-green bacteria Autotroph Atmospheric CO2 Sunlight NO3 ... 

Atomic spectroscopy, 1, 231-234 Atropisomers, 1,200 Aurintricarboxylic acid beryllium(II) complexes, 2, 482 Aurocyanides dissolution, 6,784 Autotrophic bacteria... 

Predicting the effect of the terrestrial vegetation response to C02-induced climate change for a particular site involves explicit treatment of feedbacks. These are diagramed in Figure 3. The balance between decomposition + autotrophic respiration and gross primary production (GPP) determines the net storage and release of carbon to atmosphere. Climate meets each of these... 

Carbon dioxide is produced as a result of metabolism of all heterotrophic organisms. The concentrations of CO2 in pore water of reduced sediments are therefore high. Autotrophic microorganisms consume CO2 in the oxidized part of the sediment, which can vary in depth from a meter in deep sea sediments to a few mm... 

Primary production maintains the main carbon flux from the atmosphere to the biota. In the process of photosynthesis, CO2 from the atmosphere is reduced by autotrophic organisms to a wide range of organic substances. The complex biochemistry involved can be represented by the formula... 

Several factors can influence metal uptake by stream autotrophic biofllms in fluvial systems. These include chemical factors (pH, saUnity, phosphate concentration) which affect metal bioavailabiHty by either altering the speciation of the metal or by complexing it at the biotilm s matrix and cell surfaces [18, 40], and also other biological and physical factors. 

Hill WR, Bednarek AT, Larsen XL (2000) Cadmium sorption and toxicity in autotrophic biofihns. Can J Fish Aquat Sci 57 530... 

D values of amino acids from autotrophs are directly related to the 5Dwater in the cellular and intercellular water. As food is metabolized, part of its organic hydrogen has an opportunity to... 

The reduction of ketones, aldehydes, and olefins has been extensively explored using chemical and biological methods. As the latter method, reduction by heterotrophic microbes has been widely used for the synthesis of chiral alcohols. On the contrary, the use of autotrophic photosynthetic organisms such as plant cell and algae is relatively rare and has not been explored because the method for cultivation is different from that of heterotrophic microbes. Therefore, the investigation using photosynthetic organisms may lead to novel biotransformations. 

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