Abstract
Background: The rat intestinal fatty acid-binding protein (I-FABP) is expressed in the
small intestine and is involved in the absorption and transport of dietary fatty acids. It is used as a
marker for intestinal injury and is associated with various gastrointestinal disorders. I-FABP has
been studied extensively using conventional experimental and computational techniques. However,
the detection of intrinsically disordered regions requires the application of special sampling
molecular dynamics simulations along with certain bioinformatics because conventional computational
and experimental studies face challenges in identifying the features of intrinsic disorder.
Methods: Replica exchange molecular dynamics simulations were conducted along with bioinformatics
studies to gain deeper insights into the structural properties of I-FABP. Specifically, the Cα
and Hα chemical shift values werecalculated, and the findings were compared to the experiments.
Furthermore, secondary and tertiary structure properties were also calculated, and the protein was
clustered using k-means clustering. The end-to-end distance and radius of gyration values were reported
for the protein in an aqueous solution medium. In addition, its disorder tendency was
studied using various bioinformatics tools.
Results and Conclusion: It was reported that I-FABP is a flexible protein with regions that demonstrate
intrinsic disorder characteristics. This flexibility and intrinsic disorder characteristics of IFABP
may be related to its nature in ligand binding processes.
Graphical Abstract
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