
Full text loading...
Category: Applied and Industrial Microbiology; Environmental Microbiology
An Interplay between Metabolic and Physicochemical Constraints: Lessons from the Psychrophilic Prokaryote Genomes, Page 1 of 2
< Previous page | Next page > /docserver/preview/fulltext/10.1128/9781555815813/9781555814229_Chap16-1.gif /docserver/preview/fulltext/10.1128/9781555815813/9781555814229_Chap16-2.gifAbstract:
This chapter summarizes the knowledge about the genomes of psychrophilic bacteria, a subclass of the cold-adapted bacteria, with emphasis on the specific selective features relevant to cold adaptation. A detailed analysis of the general features of genomes and proteomes from psychrophilic bacteria is presented. All investigators involved in sequencing the genomes of psychrophilic Bacteria looked for common features which would account for cold-adaptation. The genomes of psychrophilic bacteria also have the counterpart of major chaperonins such as the essential GroES GroEL complex. A remarkable observation poses interesting questions about the role of this complex. In the presence of molecular oxygen (dioxygen), this has the consequence that reactive oxygen species (ROS) are more frequent and stable for a longer time. Membrane fluidity can be increased in two ways: either by incorporating unsaturated fatty acids or by including branched-chain fatty acids in the diglycerides. Photobacterium profundum SS9 was found to exhibit enhanced proportions of both monounsaturated and polyunsaturated fatty acids when grown at a decreased temperature or elevated pressure. Three main features can be observed in the genomes and proteomes of these organisms: a variety of means to cope with ROS, a multiplicity of nucleic acid folding and unfolding devices, and, finally, a bias in the amino acid composition of their proteome.
Full text loading...
List of cold-growing bacteria for which complete genomes are available