Self-Assembling Peptides stabilize

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Bottom-up NanoBiotechnology from Membrane
proteins to BioSolar Power
Lab for Molecular Self Assembly mershin_at_mit.edu,
cookb_at_mit.edu http//web.mit.edu/lms/www/
October 12th 2006 Andreas Mershin, PhD Brian
Cook P.I. Shuguang Zhang, PhD
Self-Assembling Peptides stabilize membrane
proteins
Dog on a chip
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Surfactant/detergent peptides can be designed to
stabilize membrane proteins in unnatural
environments such as bioelectronic circuits or
sensors. Peptide stabilization can help in
crystallization studies
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1st Generation (flat monolayer) devices now in
the Boston Museum of Science. Good concept but
very low power and efficiency
lt1µm
Nature, Boston Globe AP,Reuters, CNN, NYT, FT,
BBC, etc.
Biomimicry resonates with people
4
Electric Nanoforest ZnO nanowires are
transparent, conducting tree-trunks
ZnO transparent and conducting nanowires grown
using CVD (high T) or wet deposition (low
temp) High surface area, transparent,
conducting, bio-friendly, enhancement factor
200-2000
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Self-assembled velcro
natural PsaD


ZnO-PsaD
ZnO-PS1
PS1
ITO
ZnO
PS-I
ZnO-binding peptide sequence (GLHIPTGSSYSHR)
ZnO NW
ITO
GLASS

• Direct attachment
• (less R, more I)

Device architecture
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Olfactory receptors smell background

• The mammalian nose has the ability to rapidly
  distinguish between an enormous range of small
  molecules at low concentrations
• The proteins responsible are olfactory receptors
  (ORs), a large class of sensory proteins which
  function combinatorially to allow the brain to
  discriminate odors
• Currently, the molecular mechanism by which this
  receptor set functions is unknown

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Olfactory receptors purification

• Tagged and optimized OR genes are synthesized
  (PCR-based gene assembly) then inserted into
  producer cell lines
• OR production is then induced in cell culture
  and the proteins harvested out and purified via
  the affinity tags (using HPLC)

Olfactory receptors structural functional
measurement

• Structure 2º confirmed via CD spectroscopy, 3º
  to be done with X-ray crystallography
• Function odorant binding via SPR (Biacore),
  plus other methods
• Beyond construction of prototype smell
  biosensors utilizing OR proteins