Allostery can occur by way of subtle cooperation among protein residues (e.g., 
amino acids) even in the absence of large conformational shifts. Dynamical 
network analysis has been used to model this cooperation, helping to 
computationally explain how binding to an allosteric site can impact the 
behavior of a primary site many ångstroms away. Traditionally, computational 
efforts have focused on the most optimal path of correlated motions leading from 
the allosteric to the primary active site. We present a program called Weighted 
Implementation of Suboptimal Paths (WISP) capable of rapidly identifying 
additional suboptimal pathways that may also play important roles in the 
transmission of allosteric signals. Aside from providing signal redundancy, 
suboptimal paths traverse residues that, if disrupted through pharmacological or 
mutational means, could modulate the allosteric regulation of important drug 
targets. To demonstrate the utility of our program, we present a case study 
describing the allostery of HisH-HisF, an amidotransferase from T. maritima 
thermotiga. WISP and its VMD-based graphical user interface (GUI) can be 
downloaded from http://nbcr.ucsd.edu/wisp.