TY - JOUR
T1 - Impact of a micellar environment on the conformations of two cyclic pentapeptides
AU - Bruch, M. D.
AU - Rizo-Rey, Jose
AU - Gierasch, L. M.
PY - 1992/12
Y1 - 1992/12
N2 - In an effort to explore the influence of interfacial environments on reverse turns, we have performed a detailed analysis by nmr of the solution conformations of two cyclic pentapeptides in sodium dodecyl sulfate (SDS) micelles. The first peptide, cyclo (D‐Phe1‐Pro2‐Gly3‐D‐Ala4‐Pro5), adopts a single rigid conformation in solution (either chloroform or dimethylsulfoxide) and in crystals, whereas the second, cyclo (Gly1‐Pro2‐D‐Phe3‐Gly4‐Val5), is much more flexible and adopts different conformations in the crystal and in solution. Both of these peptides are solubilized by SDS micelles, and nmr relaxation rates indicate that they are both partially immobilized by interaction with the micelles. Furthermore, some amide protons in both peptides participate in hydrogen bonds with water. In the presence of micelles, the former peptide retains a conformation essentially the same as that found in crystals and in solution, which consists of a β turn and an inverse γ turn. However, the micellar environment has a significant effect on the latter peptide. In particular, the population of a conformer containing a cis Gly‐Pro peptide bond is increased significantly. The most likely conformation of the cis isomer, determined by a combination of nmr and restrained molecular dynamics, contains a Gly1‐Pro2 δ turn and a γ turn about D‐Phe3. The nmr data on the trans isomer indicate that this isomer is averaging between two conformations that differ mainly in the orientation of the D‐Phe3‐Gly4 peptide bond. © 1992 John Wiley & Sons, Inc.
AB - In an effort to explore the influence of interfacial environments on reverse turns, we have performed a detailed analysis by nmr of the solution conformations of two cyclic pentapeptides in sodium dodecyl sulfate (SDS) micelles. The first peptide, cyclo (D‐Phe1‐Pro2‐Gly3‐D‐Ala4‐Pro5), adopts a single rigid conformation in solution (either chloroform or dimethylsulfoxide) and in crystals, whereas the second, cyclo (Gly1‐Pro2‐D‐Phe3‐Gly4‐Val5), is much more flexible and adopts different conformations in the crystal and in solution. Both of these peptides are solubilized by SDS micelles, and nmr relaxation rates indicate that they are both partially immobilized by interaction with the micelles. Furthermore, some amide protons in both peptides participate in hydrogen bonds with water. In the presence of micelles, the former peptide retains a conformation essentially the same as that found in crystals and in solution, which consists of a β turn and an inverse γ turn. However, the micellar environment has a significant effect on the latter peptide. In particular, the population of a conformer containing a cis Gly‐Pro peptide bond is increased significantly. The most likely conformation of the cis isomer, determined by a combination of nmr and restrained molecular dynamics, contains a Gly1‐Pro2 δ turn and a γ turn about D‐Phe3. The nmr data on the trans isomer indicate that this isomer is averaging between two conformations that differ mainly in the orientation of the D‐Phe3‐Gly4 peptide bond. © 1992 John Wiley & Sons, Inc.
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U2 - 10.1002/bip.360321215
DO - 10.1002/bip.360321215
M3 - Article
C2 - 1472656
AN - SCOPUS:0027006849
SN - 0006-3525
VL - 32
SP - 1741
EP - 1754
JO - Biopolymers
JF - Biopolymers
IS - 12
ER -