Alternatively, Korarchaeota in the western GB may be genetically connected with populations further west. A Y-27632 dihydrochloride broader geographic survey of Korarchaeota in the Western U.S. and a corresponding analysis of other thermophilic taxa may resolve these alternatives. Nevertheless, these data challenge the strict interpretation of Baas-Becking��s dictum ����alles is overal: maar het milieu selecteert���� and is consistent with the proposal to elevate the interpretation of ����alles���� to the level of the bacterial or archaeal genus, at least in some cases. There has been renewed interest in understanding the structural and architectural organization of proteins through a network representation of proteins. The belief is that identifying the guiding organizational principles behind protein structures will lead to uncovering the principles behind protein folding. Ever since Anfinsen��s experiment in 1973 proved that all the information for a protein to fold into its three dimensional structure is encoded in its primary sequence, many models have been developed based on a host of theoretical, simulated or experimental techniques. The chief among these are the nucleation-propagation model, the nucleation-condensation model, the sequential and hierarchical model, the collapse model and the modular model. More recently, a unified model of protein folding that is based on the effective energy surface of a poly peptide chain has been introduced by Wolynes et al. according to which protein folding consists of a progressive organization of ensembles of partially folded structures that arise through multiple routes. Regardless of the model used, they are all in agreement about the fact that small regions of proteins tend to fold separately and then are aggregated into the final structure for globular proteins by means of stabilizing interactions between the different subunits. In addition, there is broad agreement between models with the predominantly kinetic character of protein folding process: strictly speaking, a minimum energy 3D configuration can be attached to any random amino acid sequence but only those sequences having ����kinetically reachable minima���� tend to effectively fold in a finite time. This ����kinetic first���� principle is implicit in the folding funnel CHIR-99021 paradigm. Graph theory based descriptors of proteins have gained prominence in recent times and have been shown to be ideally suited for studying general topological principles of protein structures. The consideration of proteins as networks by defining the amino acids in the polypeptide chain as the nodes and the noncovalent interactions among them as links allowed us to overcome the need for ����artificial���� definitions of structural classifications such as motifs, classes, topologies, fold families and superfamilies and to identify some architectural invariants of proteins: at the upper end, we discovered a maximal size for domains at around 275 residues while at the lower end we identified six residue hydrophobic patches or ����words���� as the smallest unit containing maximal information content as defined by Shannon��s entropy.