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Department of Physics and Engineering
Optical Science Center for Applied Research (OSCAR)
Fall 2016 Seminar Series
Tuesday,November22,2016,11:00AM
NovelBiomolecularStructuralandFunctionalInformation
fromQuantumChemicalStudies
Dr.YongZhang
DepartmentofBiomedicalEngineering,Chemistry,andBiologicalSciences,StevensInstitute
ofTechnology,Hoboken,NJ
Abstract
Structure plays a key role on understanding biomolecular properties and biochemical activities, as well as
relatedbiomimeticstudies.Currentlythemostwidelyusedtechniquetodeterminebiomolecularstructureis
X-ray crystallography. But it suffers from some accuracy problems and limitations. Recently, based on the
intrinsic mathematical relationship between molecular geometry and spectroscopic property, by using the
most accurate physics in the atomic world and widely accessible spectroscopic observables, we have
developedtheIntegratedQuantumMechanicsandSpectroscopyApproachandgeneratedaccurateactivesite
structures of >20 metalloprotein systems. One example is the determination of the first atomic level HNO
boundproteinstructure.HNOplayssignificantrolesinmanybiologicalactivitiessuchasvascularrelaxation,
enzyme activity regulation, and neurological function regulation. However, details of how HNO binds with
proteinsandreactswithbiologicaltargetsarelargelyunknown.WerecentlydeterminedtheatomiclevelHNO
bound myoglobin active site, with a unique dual hydrogen bonding mode, which produced data that are in
excellentaccordwithvariousexperimentalspectroscopicresultsandstabilities.Anotherimportanttopicison
direct HNO probes for in vivo applications. Recent breakthroughs were made with CuII-based complexes
having fluorescence reporters. Their coordination environments are similar to that in Cu,Zn-superoxide
dismutase (SOD), which plays a significant role in cellular HNO/NO conversion. A quantum chemical
investigation was performed to provide structural, energetic, and electronic profiles of HNO/NO conversion
pathwaysviathefirstCuII-basedHNOprobe.Resultsnotonlyareconsistentwithexperimentalobservations,
butalsoprovidenumerousstructuralandmechanisticetailsunknownbefore,withimplicationsforCu,Zn-SOD
andmetal-basedHNOprobes.Theseresultsshallfacilitatefuturestudiesofvariousbiomolecularsystems.
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OSCAR Building, 1 Floor Seminar Room (A103)