Bioactive Inorganic Materials
(DMR0300631)
Challa V. Kumar Department of Chemistry University of Connecticut Storrs, CT 06269-3060 http://jasmin.chem.uconn.edu Challa.Kumar@UCONN.edu
Protein Stability - Energy Level Diagram
Bound unstable Free Bound stable Bound/unstable Free Bound/stable
Native
Denatured
Solids Used for Protein Binding
SEM of α-ZrP
O
O
OH
OH
OH
α-ZrP
α-ZrCMP
α-ZrCEP
Surface area ~ 5Å x 5Å per phosphate/phosphonate
Reversible Denaturation of Proteins bound to α-ZrP/Phosphonates
Hb/α-ZrP (90˚C/5 min)
heat
Cooling (2hr)
cool
3 mM guaiacol 0.52 mMO2 H 2 A 0.05 0.4 µM Hb/7.1 mM ZrP B S O 0.04 R B 0.03 heated 90°C 5 min /cool A native 2 hrs 25°C N C 0.02 E no heat : 1 -4 A/s x 10 0.01 heated : 1.3-4 A/s x 10 0 0 50 100 150 200 250 300 350 400 Time/sec
0.06
GO/Ca I N T E N S I T Y
+2
/ZrCEP
renatured
native
0
100
200 Time/s
300
400
Micropor. Mesopor. Mater., in Press 2004
Thermodynamics of Hb Binding to α-ZrP
29.2 85µMHb / 0.25mM Z Dilution
29
Hb
28.8
µcal / sec
ZrP
28.6
Q
28.4
28.2
28 0
Single-site Binding Model n1= 0.016 K1 = 9.1*105 M-1 ∆H = - 2.9 * 104 J/mol ∆S = -70.43 e.u.
10002000300040005000600070008000
Time (sec)
Micropor. Mesopor. Mater., in Press 2004
Thermal Annealing of Lysozyme Bound to α-ZrP
12.5
MHC: Lys(0.429mg/ml)/ZrP 10 mM Phosphate Buffer pH 7.16 (1 Scan For Each)
No annealing After 30 min annealing
12
11.5 C (Kcal/ Kmol)
11 After 0 min annealing
p
10.5 MHC lys ZRP 30 min scan 1 10 MHC lys ZRP 0 min scan 1 9.5 30 40 50 MHClysZrP no annealing scan 1 60 70
o
80 C
90
100
110
Temperature,
Untreated Sample ∆H kcal/mol ∆S kcal/mol Tm / ˚C 101+4.3 0.32+0.01 49.8 + 0.8
0 Min. annealing 71+1.0 0.20+0.01 86.5 + 0.1
30 Min. annealing 86+15 0.24+0.02 87 + 1