Effects of divalent metals on nanoscopic fiber formation and small molecule recognition of helical proteins

Susheel K. Gunasekar, Luona Anjia, Hiroshi Matsui, Jin Montclare

Research output: Contribution to journalArticle

Abstract

Metal dependent protein-based assemblies derived from the cartilage oligomeric matrix protein (C) coiled-coil domain (His 6-C) and two variants with mutation at position 40 (His 6-T40A) and 44 (His 6-L44A) are explored. All proteins have an N-terminal hexahistidine tag (His 6) that interacts with divalent metal ions Zn(II) and Ni(II). Binding to Zn(II) confers enhanced helical structure and stability, while Ni(II) promotes aggregation. Surprisingly, His 6-L44A undergoes a conformational switch from unstructured to α-helix in the presence of Zn(II). Both His 6-C and His 6-T40A further assemble into discrete nanofibers that appear to be stabilized by Zn(II) in which the fiber formation is dictated by the α-helical content. Because Ni(II) promotes aggregation, the proteins visibly cluster, forming large fiber mats in the case of His 6-C and His 6-T40A or aggregated structures as observed for His 6-L44A. Due to the unique pentameric assembly of the proteins, recognition of a small molecule within the pore is assessed using curcumin as the guest molecule. In the presence of Zn(II), there is enhanced binding to curcumin, while the addition of Ni(II) causes a loss in binding. It is shown that metal binding serves as a trigger to control the conformation of the proteins, affecting the nanoscopic fibrous assemblies and small molecule recognition abilities.

Original languageEnglish (US)
Pages (from-to)2154-2159
Number of pages6
JournalAdvanced Functional Materials
Volume22
Issue number10
DOIs
StatePublished - May 23 2012

Fingerprint

His-His-His-His-His-His
Metals
proteins
Proteins
Molecules
fibers
Fibers
metals
molecules
assemblies
Agglomeration
Curcumin
cartilage
Cartilage
mutations
Nanofibers
helices
Metal ions
Conformations
metal ions

Keywords

  • coiled-coils
  • fibers
  • metals
  • self-assembly
  • small molecule recognition
  • stimuli-responsive materials

ASJC Scopus subject areas

  • Biomaterials
  • Electrochemistry
  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

Effects of divalent metals on nanoscopic fiber formation and small molecule recognition of helical proteins. / Gunasekar, Susheel K.; Anjia, Luona; Matsui, Hiroshi; Montclare, Jin.

In: Advanced Functional Materials, Vol. 22, No. 10, 23.05.2012, p. 2154-2159.

Research output: Contribution to journalArticle

Gunasekar, Susheel K. ; Anjia, Luona ; Matsui, Hiroshi ; Montclare, Jin. / Effects of divalent metals on nanoscopic fiber formation and small molecule recognition of helical proteins. In: Advanced Functional Materials. 2012 ; Vol. 22, No. 10. pp. 2154-2159.
@article{adf5cea92f4348cbb1140b370b0e47cb,
title = "Effects of divalent metals on nanoscopic fiber formation and small molecule recognition of helical proteins",
abstract = "Metal dependent protein-based assemblies derived from the cartilage oligomeric matrix protein (C) coiled-coil domain (His 6-C) and two variants with mutation at position 40 (His 6-T40A) and 44 (His 6-L44A) are explored. All proteins have an N-terminal hexahistidine tag (His 6) that interacts with divalent metal ions Zn(II) and Ni(II). Binding to Zn(II) confers enhanced helical structure and stability, while Ni(II) promotes aggregation. Surprisingly, His 6-L44A undergoes a conformational switch from unstructured to α-helix in the presence of Zn(II). Both His 6-C and His 6-T40A further assemble into discrete nanofibers that appear to be stabilized by Zn(II) in which the fiber formation is dictated by the α-helical content. Because Ni(II) promotes aggregation, the proteins visibly cluster, forming large fiber mats in the case of His 6-C and His 6-T40A or aggregated structures as observed for His 6-L44A. Due to the unique pentameric assembly of the proteins, recognition of a small molecule within the pore is assessed using curcumin as the guest molecule. In the presence of Zn(II), there is enhanced binding to curcumin, while the addition of Ni(II) causes a loss in binding. It is shown that metal binding serves as a trigger to control the conformation of the proteins, affecting the nanoscopic fibrous assemblies and small molecule recognition abilities.",
keywords = "coiled-coils, fibers, metals, self-assembly, small molecule recognition, stimuli-responsive materials",
author = "Gunasekar, {Susheel K.} and Luona Anjia and Hiroshi Matsui and Jin Montclare",
year = "2012",
month = "5",
day = "23",
doi = "10.1002/adfm.201101627",
language = "English (US)",
volume = "22",
pages = "2154--2159",
journal = "Advanced Materials for Optics and Electronics",
issn = "1057-9257",
publisher = "Wiley-VCH Verlag",
number = "10",

}

TY - JOUR

T1 - Effects of divalent metals on nanoscopic fiber formation and small molecule recognition of helical proteins

AU - Gunasekar, Susheel K.

AU - Anjia, Luona

AU - Matsui, Hiroshi

AU - Montclare, Jin

PY - 2012/5/23

Y1 - 2012/5/23

N2 - Metal dependent protein-based assemblies derived from the cartilage oligomeric matrix protein (C) coiled-coil domain (His 6-C) and two variants with mutation at position 40 (His 6-T40A) and 44 (His 6-L44A) are explored. All proteins have an N-terminal hexahistidine tag (His 6) that interacts with divalent metal ions Zn(II) and Ni(II). Binding to Zn(II) confers enhanced helical structure and stability, while Ni(II) promotes aggregation. Surprisingly, His 6-L44A undergoes a conformational switch from unstructured to α-helix in the presence of Zn(II). Both His 6-C and His 6-T40A further assemble into discrete nanofibers that appear to be stabilized by Zn(II) in which the fiber formation is dictated by the α-helical content. Because Ni(II) promotes aggregation, the proteins visibly cluster, forming large fiber mats in the case of His 6-C and His 6-T40A or aggregated structures as observed for His 6-L44A. Due to the unique pentameric assembly of the proteins, recognition of a small molecule within the pore is assessed using curcumin as the guest molecule. In the presence of Zn(II), there is enhanced binding to curcumin, while the addition of Ni(II) causes a loss in binding. It is shown that metal binding serves as a trigger to control the conformation of the proteins, affecting the nanoscopic fibrous assemblies and small molecule recognition abilities.

AB - Metal dependent protein-based assemblies derived from the cartilage oligomeric matrix protein (C) coiled-coil domain (His 6-C) and two variants with mutation at position 40 (His 6-T40A) and 44 (His 6-L44A) are explored. All proteins have an N-terminal hexahistidine tag (His 6) that interacts with divalent metal ions Zn(II) and Ni(II). Binding to Zn(II) confers enhanced helical structure and stability, while Ni(II) promotes aggregation. Surprisingly, His 6-L44A undergoes a conformational switch from unstructured to α-helix in the presence of Zn(II). Both His 6-C and His 6-T40A further assemble into discrete nanofibers that appear to be stabilized by Zn(II) in which the fiber formation is dictated by the α-helical content. Because Ni(II) promotes aggregation, the proteins visibly cluster, forming large fiber mats in the case of His 6-C and His 6-T40A or aggregated structures as observed for His 6-L44A. Due to the unique pentameric assembly of the proteins, recognition of a small molecule within the pore is assessed using curcumin as the guest molecule. In the presence of Zn(II), there is enhanced binding to curcumin, while the addition of Ni(II) causes a loss in binding. It is shown that metal binding serves as a trigger to control the conformation of the proteins, affecting the nanoscopic fibrous assemblies and small molecule recognition abilities.

KW - coiled-coils

KW - fibers

KW - metals

KW - self-assembly

KW - small molecule recognition

KW - stimuli-responsive materials

UR - http://www.scopus.com/inward/record.url?scp=84861147532&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84861147532&partnerID=8YFLogxK

U2 - 10.1002/adfm.201101627

DO - 10.1002/adfm.201101627

M3 - Article

AN - SCOPUS:84861147532

VL - 22

SP - 2154

EP - 2159

JO - Advanced Materials for Optics and Electronics

JF - Advanced Materials for Optics and Electronics

SN - 1057-9257

IS - 10

ER -