Revealing protein sequence organization via contiguous hydrophobicity with the blobulator toolkit.

Clusters of hydrophobic residues are known to promote structured protein stability and drive protein aggregation. Recent work has shown that identifying contiguous hydrophobic residue clusters within protein sequences (termed "blobs") has proven useful in both intrinsically disordered protein (IDP) simulation and human genome studies. However, an accessible toolkit was unavailable, and the role that blobs play across the structural context of a variety of protein families remained unclear. Here, we present the toolkit: consisting of a webtool, a command line interface, and a VMD plugin. We demonstrate how identifying blobs using biologically relevant parameters provides useful information about a globular protein, two orthologous membrane proteins, and an IDP. Other potential applications are discussed, including: predicting protein segments with critical roles in tertiary interactions, providing a definition of local order and disorder with clear edges, and aiding in predicting protein features from sequence. The webtool can be found at www.blobulator.branniganlab.org, and the source code with pip installable command line tool, as well as the VMD plugin with installation instructions, can be found on GitHub at www.GitHub.com/BranniganLab/blobulator.