Allostery is one of most important processes in molecular biology by which proteins transmit the information from one functional site to another, frequently distant site. The information on ligand binding or on posttranslational modification at one site is transmitted along allosteric communication path to another functional site allowing for regulation of protein activity. The detailed analysis of the general character of allosteric communication paths is therefore extremely important. It enables to better understand the mechanism of allostery and can be used in for the design of new generations of drugs. Considering all the PDB annotated allosteric proteins (from ASD  AlloSteric Database) belonging to four different classes (kinases, nuclear receptors, peptidases and transcription factors), this work has attempted to decipher certain consistent patterns present in the residues constituting the allosteric communication subsystem (ACSS). The thermal fluctuations of hydrophobic residues in ACSSs were found to be significantly higher than those present in the non ACSS part of the same proteins, while polar residues showed the opposite trend. The basic residues and hydroxyl residues were found to be slightly more predominant than the acidic residues and amide residues in ACSSs, hydrophobic residues were found extremely frequently in kinase ACSSs. Despite having differentmore »
Nimber Sequences of NodeKayles Games
NodeKayles is an impartial game played on a simple graph. The SpragueGrundy
theorem states that every impartial game is associated with a nonnegative integer
value called a Nimber. This paper studies the Nimber sequences of various families of
graphs, including 3paths, lattice graphs, prism graphs, chained cliques, linked cliques,
linked cycles, linked diamonds, hypercubes, and generalized Petersen graphs. For most
of these families, we determine an explicit formula or a recursion on their Nimber
sequences.
 Award ID(s):
 1852378
 Publication Date:
 NSFPAR ID:
 10141270
 Journal Name:
 Journal of integer sequences
 Volume:
 23
 ISSN:
 15307638
 Sponsoring Org:
 National Science Foundation
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