Biomolecules alkanes

Further work at EniTecnologies was conducted with Rhodococcus strains. Rhodococ-cus was selected for its metabolical versatility, easy availability in soils and water, and remarkable solvent tolerance. Its capabilities for catalyzing diverse transformation reactions of crude oils, such as sulfur removal, alkanes and aromatics oxidation and catabolism caught their attention. Hence, genetic tools for the engineering of Rhodococcus strains have been applied to improve its biotransformation performance and its tolerance to certain common contaminants of the crude oil, such as cadmium. The development of active biomolecules led to the isolation and characterization of plasmid vectors and promoters. Strains have been constructed in which the careful over-expression of selected components of the desulfurization pathway leads to the enhancement of the sulfur removal activity in model systems. Rhodococcus, Gordona, and Nocardia were transformed in this way trying to improve their catalytic performance in BDS. In a... 

Studying alkanes also provides an opportunity to learn about lipids, a group of biomolecules similar to alkanes, in that they are composed mainly of nonpolar carbon-carbon and carbon-hydrogen a bonds. Section 4.15 serves as a brief introduction only, so we will return to lipids in Chapters 10 and 29. 

Lipids are biomolecules whose properties resemble those of alkanes and other hydrocarbons. They are unlike any other class of biomolecules, though, because they are defined by a physical property, not by the presence of a particular functional group. 

The combustion of alkanes, the concentration of atmospheric carbon dioxide, and global warming (Section 4.14B) An introduction to lipids, biomolecules whose properties can be explained by understanding alkane chemistry cholesterol in the cell membrane (Section 4.15)... 

MD simulations of lipid bilayers as a function of temperature have not been extensive. The reliability of force fields is dependent on the accuracy of describing the torsional potential energies of alkanes which prompted improvements of some of the most commonly applied force fields for biomolecules [125] using recent ab initio computations of torsional potential in various trans/gauche n-alkanes (up to -decane) [126]. A few recent MD simulations have analyzed the temperature effects on models of PC lipid bUayers, mainly for long chains (16-18 C), with a reasonably successful prediction of the phase transition temperamre (error of 12-50 °C) [106, 127-130]. These studies relate the melting temperamre to the fast increase of gauche conformers in the alkyl chains. 

Most life processes are based on the reactions of functional groups. Since alkanes have no functional group, they are not abundant in the human body. However, most compounds in human cells contain parts consisting solely of carbon and hydrogen that behave very much like hydrocarbons. Thus, to understand the chemical properties of the more complex biomolecules, it is useful to have some understanding of the structure, physical properties, and chemical behavior of hydrocarbons. 

Systematic names drop the final -e of the alkane and add the suffix -amine, as in ethanamine. However, there is still wide usage of common names, in which the suffix -amine follows the name of the alkyl group thus, methylamine has one methyl group attached to N, diethylamine has two ethyl groups attached, and so forth. Figure 15.12 shows that the amine functional group occurs in many biomolecules. 

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