Exploring the interaction between Fe 3+ and REGLE motif of the
high-affinity iron permease (Ftr1): an in silico approach
Abstract
Mucormycosis is an invasive fungal infection with considerably high
mortality rates in immunocompromised individuals. Due to COVID-19
pandemic, the disease has resurfaced recently and lack of appropriate
antifungals resulted in a poor outcome in patients. The iron uptake
mechanism in Rhizopus delemar, the predominant causal agent is
crucial for its survival and pathogenesis in human host. The current
study focuses on the structural dynamics of high affinity iron permease
(Ftr1) which act as a virulence factor in this fatal fungal disease.
Ftr1 is a transmembrane protein which is responsible for the transport
of Fe 3+ ion from the extracellular milieu to the
cytoplasm under iron-starving conditions in Rhizopus. In this
work, the three-dimensional modelling of Ftr1 was carried out and it was
found to possess seven transmembrane helices with N-terminal lying in
the extracellular region and C-terminal in the intracellular region.
Moreover, the present study delineates the interaction of glutamic acid
residues, found in the REGLE motif of the fourth transmembrane helix
with Fe 3+. The molecular dynamics (MD) simulation
study revealed that the glycine present in the motif destabilizes the
helix thereby bringing E157 closer to the positively charged ion.
Understanding the interaction between Fe 3+ ion and
Ftr1 would be helpful in designing effective small molecule drugs
against this novel therapeutic target for treating mucormycosis.