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PRODID:UW-Madison-Physics-Events
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UID:UW-Physics-Event-1299
DTSTART:20090206T220000Z
DURATION:PT1H0M0S
DTSTAMP:20260420T040543Z
LAST-MODIFIED:20090202T150229Z
LOCATION:2241 Chamberlin Hall (coffee and cookies at 3:30 pm)
SUMMARY:Exploiting protein-crystal interactions to build switches\, th
 rottles and brakes: what shells\, bones and kidney stones can teach us
  about managing CO2\, Physics Department Colloquium\, James J. De Yore
 o\, Molecular Foundry\, LBNL
DESCRIPTION:Coal is the major source of energy for electrical generati
 on across the globe.  In the United States\, it provides about a third
  of our electricity\, while in China\, where coal accounts for over 75
 % of electrical generation\, a new coal-burning power plant comes on l
 ine every week.  But coal is amongst the most intense sources of green
 house gases\, producing nearly three tons of CO2 for every ton of coal
  consumed and contributing 40% of all anthropogenic CO2.  Moreover\, c
 oal is an essential constituent in about 65% of all steel production. 
  With oil nearing peak production\, nuclear energy likely to be slow i
 n coming on line\, solar and other renewables still in their infancy\,
  and no obvious substitute for coking steel\, the world will continue 
 to rely on coal for decades to come.  So what are we going to do with 
 all of that carbon?  The answer may lie in the workings of tiny marine
  organisms\, which transform CO2 into structural materials made of cal
 cium carbonate through a process known as biomineralization.  Similar 
 processes direct the growth of bones and teeth and prevent formation o
 f kidney stones.  The interaction of proteins with inorganic constitue
 nts is a defining feature of biomineralization.  An understanding of t
 he structural relationships\, adsorption dynamics and resulting contro
 l mechanisms may one day enable us to mimic the process.  In this talk
  I will present results from in situ AFM investigations of peptide and
  protein interactions with growing crystal surfaces in which cantileve
 rs designed to maximize tip-sharpness while minimizing contact force w
 ere used to obtain true single-molecule resolution.  Analysis of the r
 esults reveals how the slow adsorption dynamics\, strong electrostatic
  interactions and tendency towards aggregation peculiar to macromolecu
 les lead to unexpected and varied controls on crystal growth.  For exa
 mple\, when the timescales for peptide adsorption and step advancement
  overlap\, minute changes in growth conditions lead to rapid switching
  between two stable states of growth.  Physical models based on the th
 ermodynamics of steps on crystal surfaces and the dynamics of peptide 
 adsorption provide an understanding of the observed behavior.  The fin
 dings suggest strategies for sequestering CO2 by directing the timing 
 and rate of carbonate formation in subsurface reservoirs through the u
 se of protein-like molecules as "switches\, throttles and brakes".
URL:https://www.physics.wisc.edu/events/?id=1299
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