BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//RLASKEY//CALENDEROUS//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
BEGIN:VEVENT
DTSTAMP:20260825T002132Z
LAST-MODIFIED:20121116T203436Z
DTSTART:20080418T173000Z
DTEND:20080418T183000Z
UID:event259@bu.edu
URL:http://physics.bu.edu/internal/events/show/259
SUMMARY:Force-induced single molecule DNA interactions: From small molecule
	 binding to HIV replication
DESCRIPTION:Featuring Mark C. Williams\, Northeastern University\nHosted by
	: Mikkel Jensen\n\nPart of the Biophysics/Condensed Matter Seminar Series.\
	n\nAbstract: When single DNA molecules are stretched\, mechanical work is p
	erformed that can induce structural and thermodynamic changes that alter DN
	A interactions in a measurable manner. Using an optical tweezers instrument
	\, we obtain the force required to extend the DNA molecule and to convert d
	ouble-stranded DNA into single-stranded DNA in the presence of binding liga
	nds\, which we refer to as force-induced melting. Depending on the nature o
	f the ligand binding mode\, several different effects are observed. For exa
	mple\, intercalators such as ethidium increase the contour length of double
	-stranded DNA as well as the melting force\, allowing for measurement of fo
	rce-dependent and zero force intercalation affinity. In contrast\, single-s
	tranded DNA binding proteins\, such as T4 gene 32 protein\, strongly destab
	ilize double-stranded DNA\, resulting in a decrease in melting force. The o
	bserved decrease in melting force as a function of protein concentration al
	lows us to quantify the protein binding free energy\, providing insights in
	to the function of these proteins during viral replication. Finally\, DNA s
	tretching allows us to characterize the mechanism by which retroviral nucle
	ocapsid proteins facilitate rearrangements of nucleic acid secondary struct
	ure\, which are required for reverse transcription and retroviral replicati
	on.
LOCATION:SCI 352\, 590 Commonwealth Avenue\, 02215
STATUS:CONFIRMED
CLASS:PUBLIC
END:VEVENT
END:VCALENDAR