Conformational behavior of poly‐N5‐(3‐hydroxypropyl)‐<scp>L</scp>‐glutamine in water–methanol mixtures studied by 13C nmr and CD spectroscopy

Blasi, R. Di; Verdini, A. S.

doi:10.1002/bip.1974.360131105

Cited by 9 publications

(1 citation statement)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…25 They have shown that lowmolecular-weight poly[N5-(3-hydroxy propy1)~-glutamine] in water/ methanol mixtures exhibits peak doubling in the carbon-13 nmr spectrum. On fractionation, the double-peak character is reduced.…”

Section: Resultsmentioning

confidence: 99%

Origin of multipeak behavior in the NMR spectra of poly(L‐glutamic acid)

Lader

Mandelkern

1979

Biopolymers

View full text Add to dashboard Cite

SynopsisThe previous report that poly (L-glutamic acid) exhibits doubled resonances in the helix-coil transition region by either proton or carbon-13 nmr resolves the question of whether or not this behavior is limited to uncharged polypeptides in organic solvents, as had been previously thought. In the present work, we show that the underlying principle causing this anomalous double-peak behavior is due to molecular-weight polydispersity of the sample. The molecular-weight range in which this phenomenon is observed is largely dependent on the values of u, the nucleation or cooperativity factor. The principles developed are shown to encompass all classes of polypeptides in a very natural way and to explain the key experimental data in the literature.

show abstract

Section: Resultsmentioning

confidence: 99%

Origin of multipeak behavior in the NMR spectra of poly(L‐glutamic acid)

Lader

Mandelkern

1979

Biopolymers

View full text Add to dashboard Cite

show abstract

A nuclear magnetic resonance study of the helix–coil transition of poly(L‐glutamic acid)

1977

View full text Add to dashboard Cite

SynopsisThere have been many reports that the nuclear magnetic resonance (nrnr) spectra of a large number of polypeptides exhibit peak doubling of the a-carbon and the a-carbon proton in the helix-coil transition region. One apparent exception to this generalization has been polypeptides with ionizable side chains, where the helix-coil transition is induced by changes in pH in aqueous solution. Because it is important to establish the proper theoretical reason for the peak doubling and its relation to the rate of conformational change of amino acid residues, we have reexamined the proton and carbon-13 nrnr spectra, a t high field, for two polydisperse samples of poly(L-glutamic acid). Doubling of the a-carbon proton resonance as well as those of the a-and &carbon, and backbone carbonyl are observed for a low-molecular-weight sample (DP = 54), while a higher molecular weight sample (DP = 309), exhibits only single resonances. Thus, polydispersity by itself is not sufficient to observe peak doubling; low-molecular weight is also required.

show abstract

Determination of the solid state conformation of poly[N⁵‐(2‐hydroxyethyl)‐L‐glutamine] from X‐ray diffraction

Spadon¹,

Verdini²,

Prà³

1978

Biopolymers

View full text Add to dashboard Cite

Conformational behavior of poly‐N⁵‐(3‐hydroxypropyl)‐L‐glutamine in water–methanol mixtures studied by ¹³C nmr and CD spectroscopy

Cited by 9 publications

References 26 publications

Origin of multipeak behavior in the NMR spectra of poly(L‐glutamic acid)

Origin of multipeak behavior in the NMR spectra of poly(L‐glutamic acid)

A nuclear magnetic resonance study of the helix–coil transition of poly(L‐glutamic acid)

Determination of the solid state conformation of poly[N⁵‐(2‐hydroxyethyl)‐L‐glutamine] from X‐ray diffraction

Contact Info

Product

Resources

About

Conformational behavior of poly‐N5‐(3‐hydroxypropyl)‐L‐glutamine in water–methanol mixtures studied by 13C nmr and CD spectroscopy

Cited by 9 publications

References 26 publications

Origin of multipeak behavior in the NMR spectra of poly(L‐glutamic acid)

Origin of multipeak behavior in the NMR spectra of poly(L‐glutamic acid)

A nuclear magnetic resonance study of the helix–coil transition of poly(L‐glutamic acid)

Determination of the solid state conformation of poly[N5‐(2‐hydroxyethyl)‐L‐glutamine] from X‐ray diffraction

Contact Info

Product

Resources

About

Conformational behavior of poly‐N⁵‐(3‐hydroxypropyl)‐L‐glutamine in water–methanol mixtures studied by ¹³C nmr and CD spectroscopy

Determination of the solid state conformation of poly[N⁵‐(2‐hydroxyethyl)‐L‐glutamine] from X‐ray diffraction