BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//RLASKEY//CALENDEROUS//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
BEGIN:VEVENT
DTSTAMP:20261018T105140Z
LAST-MODIFIED:-11130T050000Z
DTSTART:20120426T140000Z
DTEND:20120426T150000Z
UID:event915@bu.edu
URL:http://physics.bu.edu/internal/events/show/915
SUMMARY:Neurophotonic Rhodopsins: Spectroscopic Characterization of Neurona
	l Triggers\, Silencers\, and in vivo Voltage Sensors
DESCRIPTION:Featuring John Ogren\n\nPart of the Preliminary Oral Exam.\n\nE
	xamining Committee:\nKenneth Rothschild (Advisor)\nShyamsunder ErramilliXue
	 Han\nRobert Carey\nClaudio Chamon\n \nAbstract:\nArchaerhodopsin-3 (A
	R3) is a light driven proton pump found in Halorubrum Sodomese.  Recen
	t studies have shown that AR3 and some of its mutants can be used both as e
	ffective genetically targetable neuronal silencers and as in vivo fluoresce
	nt sensors of membrane potential.  AR3 has a 73% sequence similarity w
	ith the more extensively studied bacteriorhodopsin (BR) proton pump from Ha
	lobacterium Halobium but unlike BR\, very little is known about the details
	 of AR3’s structure\, photocycle\, and molecular mechanism of proton 
	transport.  My work applies a series of spectroscopic techniques inclu
	ding time resolved FTIR difference spectroscopy and near-IR resonance Raman
	 spectroscopy with site-directed mutagenesis to compare the role of specifi
	c amino acid residues and water molecules in the structure and function of 
	BR and AR3.  Recently\, using FTIR difference spectroscopy\, I have fo
	und important differences between BR and AR3 in the region beyond 3600 cm-1
	 which reflects structural changes in internal water molecules which are th
	ought to be essential to the BR proton pumping mechanism.  In addition
	\, I have also found evidence that the proton uptake and Schiff base reprot
	onation mechanism which involves specific Asp and Glu residues may differ s
	ignificantly from BR.  These results and continued works will help ide
	ntify conserved elements in BR-like proton pumps as well as help to bioengi
	neer improved variants of AR3 to optimize neural silencing and voltage sens
	ing. 
LOCATION:SCI 352\, 590 Commonwealth Avenue\, 02215
STATUS:CONFIRMED
CLASS:PUBLIC
END:VEVENT
END:VCALENDAR