Open Access. Powered by Scholars. Published by Universities.®

Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

FIU Electronic Theses and Dissertations

Photoacoustic calorimetry

Articles 1 - 2 of 2

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Thermodynamics And Kinetics Of Ligand Photodissociation In Heme Proteins And Formation Of Dna I-Motif, David S. Butcher Mar 2017

Thermodynamics And Kinetics Of Ligand Photodissociation In Heme Proteins And Formation Of Dna I-Motif, David S. Butcher

FIU Electronic Theses and Dissertations

Heme proteins carry out a diverse array of functions in vivo while maintaining a well-conserved 3-over-3 α-helical structure. Human hemoglobin (Hb) is well-known for its oxygen transport function. Type 1 non-symbiotic hemoglobins (nsHb1) in plants and bacterial flavohemoglobins (fHb) from a variety of bacterial species have been predicted to carry out a nitric oxide dioxygenase function. In nsHb1 and fHb this function has been linked to protection from nitrosative stress. Herein, I combine photoacoustic calorimetry (PAC), transient absorption spectroscopy (TA), and classical molecular dynamics (cMD) simulations to characterize molecular mechanism of diatomic ligand interactions with a hexa-coordinate globin from plant ...


Conformational Dynamics Associated With Ligand Binding To Vertebrate Hexa-Coordinate Hemoglobins, Luisana Astudillo Mar 2014

Conformational Dynamics Associated With Ligand Binding To Vertebrate Hexa-Coordinate Hemoglobins, Luisana Astudillo

FIU Electronic Theses and Dissertations

Neuroglobin (Ngb) and cytoglobin (Cygb) are two new additions to the globin family, exhibiting heme iron hexa-coordination, a disulfide bond and large internal cavities. These proteins are implicated in cytoprotection under hypoxic-ischemic conditions, but the molecular basis of their cytoprotective function is unclear.

Herein, a photothermal and spectroscopic study of the interactions of diatomic ligands with Ngb, Cygb, myoglobin and hemoglobin is presented. The impact of the disulfide bond in Ngb and Cygb and role of conserved residues in Ngb His64, Val68, Cys55, Cys120 and Tyr44 on conformational dynamics associated with ligand binding/dissociation were investigated. Transient absorption and photoacoustic ...