Imaging two-dimensional crystals of catalase by atomic force microscopy

Satomi Ohnishi, Masahiko Hara, Taiji Furuno, Hiroyuki Sasabe

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

Two-dimensional (2D) crystals of a water-soluble protein, catalase, were imaged in water using atomic force microscopy (AFM). The catalase molecules formed a 2D ordered monolayer by binding to a charged polypeptide monolayer of poly(1-benzyl-L-histidine) (PBLH) spread at the air-water interface. The film of PBLH, bound to catalase molecules, was horizontally transferred onto an alkylated silicon wafer for AFM imaging. The AFM images revealed that the 2D catalase crystal is composed of an array of tetramers. We also found that the pH of the sample during preparation strongly affected the quality of the AFM image because of the imaging resolution influence upon the force acting between the cantilever and the sample. The optimum sample pH was 6.0, at which a weak adhesive force in the range of 10-10 10-11 N was detected. From the results of investigation of the pH dependence of the sample during preparation on catalase-PBLH sample, it was demonstrated that the electrostatic force between the cantilever and the sample could be reduced as a result of charge cancellation at the catalase-PBLH interface (self-screening effect). We present 2D crystal images of catalase molecules acquired through AFM with molecular resolution, and demonstrate that sample preparation in which pH is optimized to induce the self-screening effect of surface charges is advantageous for AFM imaging of water-soluble protein molecules, because the electrostatic force can be controlled by changing the binding condition of the protein.

Original languageEnglish
Pages (from-to)6233-6238
Number of pages6
JournalJapanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers
Volume35
Issue number12 A
Publication statusPublished - 1996 Dec

Fingerprint

catalase
Atomic force microscopy
atomic force microscopy
histidine
Imaging techniques
Crystals
crystals
Molecules
Electrostatic force
Proteins
proteins
Water
Monolayers
Screening
preparation
water
molecules
screening
electrostatics
Polypeptides

Keywords

  • Air-water interface
  • Atomic force microscopy (AFM)
  • Catalase
  • Electrostatic interaction
  • Poly(1-benzyl-L-histidine) (PBLH)
  • Self-screening effect
  • Two-dimensional crystal
  • Water-soluble protein

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)
  • Engineering(all)

Cite this

Imaging two-dimensional crystals of catalase by atomic force microscopy. / Ohnishi, Satomi; Hara, Masahiko; Furuno, Taiji; Sasabe, Hiroyuki.

In: Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers, Vol. 35, No. 12 A, 12.1996, p. 6233-6238.

Research output: Contribution to journalArticle

Ohnishi, Satomi ; Hara, Masahiko ; Furuno, Taiji ; Sasabe, Hiroyuki. / Imaging two-dimensional crystals of catalase by atomic force microscopy. In: Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers. 1996 ; Vol. 35, No. 12 A. pp. 6233-6238.
@article{e43344bb25d54835b15535315aae56a6,
title = "Imaging two-dimensional crystals of catalase by atomic force microscopy",
abstract = "Two-dimensional (2D) crystals of a water-soluble protein, catalase, were imaged in water using atomic force microscopy (AFM). The catalase molecules formed a 2D ordered monolayer by binding to a charged polypeptide monolayer of poly(1-benzyl-L-histidine) (PBLH) spread at the air-water interface. The film of PBLH, bound to catalase molecules, was horizontally transferred onto an alkylated silicon wafer for AFM imaging. The AFM images revealed that the 2D catalase crystal is composed of an array of tetramers. We also found that the pH of the sample during preparation strongly affected the quality of the AFM image because of the imaging resolution influence upon the force acting between the cantilever and the sample. The optimum sample pH was 6.0, at which a weak adhesive force in the range of 10-10 10-11 N was detected. From the results of investigation of the pH dependence of the sample during preparation on catalase-PBLH sample, it was demonstrated that the electrostatic force between the cantilever and the sample could be reduced as a result of charge cancellation at the catalase-PBLH interface (self-screening effect). We present 2D crystal images of catalase molecules acquired through AFM with molecular resolution, and demonstrate that sample preparation in which pH is optimized to induce the self-screening effect of surface charges is advantageous for AFM imaging of water-soluble protein molecules, because the electrostatic force can be controlled by changing the binding condition of the protein.",
keywords = "Air-water interface, Atomic force microscopy (AFM), Catalase, Electrostatic interaction, Poly(1-benzyl-L-histidine) (PBLH), Self-screening effect, Two-dimensional crystal, Water-soluble protein",
author = "Satomi Ohnishi and Masahiko Hara and Taiji Furuno and Hiroyuki Sasabe",
year = "1996",
month = "12",
language = "English",
volume = "35",
pages = "6233--6238",
journal = "Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes",
issn = "0021-4922",
publisher = "Japan Society of Applied Physics",
number = "12 A",

}

TY - JOUR

T1 - Imaging two-dimensional crystals of catalase by atomic force microscopy

AU - Ohnishi, Satomi

AU - Hara, Masahiko

AU - Furuno, Taiji

AU - Sasabe, Hiroyuki

PY - 1996/12

Y1 - 1996/12

N2 - Two-dimensional (2D) crystals of a water-soluble protein, catalase, were imaged in water using atomic force microscopy (AFM). The catalase molecules formed a 2D ordered monolayer by binding to a charged polypeptide monolayer of poly(1-benzyl-L-histidine) (PBLH) spread at the air-water interface. The film of PBLH, bound to catalase molecules, was horizontally transferred onto an alkylated silicon wafer for AFM imaging. The AFM images revealed that the 2D catalase crystal is composed of an array of tetramers. We also found that the pH of the sample during preparation strongly affected the quality of the AFM image because of the imaging resolution influence upon the force acting between the cantilever and the sample. The optimum sample pH was 6.0, at which a weak adhesive force in the range of 10-10 10-11 N was detected. From the results of investigation of the pH dependence of the sample during preparation on catalase-PBLH sample, it was demonstrated that the electrostatic force between the cantilever and the sample could be reduced as a result of charge cancellation at the catalase-PBLH interface (self-screening effect). We present 2D crystal images of catalase molecules acquired through AFM with molecular resolution, and demonstrate that sample preparation in which pH is optimized to induce the self-screening effect of surface charges is advantageous for AFM imaging of water-soluble protein molecules, because the electrostatic force can be controlled by changing the binding condition of the protein.

AB - Two-dimensional (2D) crystals of a water-soluble protein, catalase, were imaged in water using atomic force microscopy (AFM). The catalase molecules formed a 2D ordered monolayer by binding to a charged polypeptide monolayer of poly(1-benzyl-L-histidine) (PBLH) spread at the air-water interface. The film of PBLH, bound to catalase molecules, was horizontally transferred onto an alkylated silicon wafer for AFM imaging. The AFM images revealed that the 2D catalase crystal is composed of an array of tetramers. We also found that the pH of the sample during preparation strongly affected the quality of the AFM image because of the imaging resolution influence upon the force acting between the cantilever and the sample. The optimum sample pH was 6.0, at which a weak adhesive force in the range of 10-10 10-11 N was detected. From the results of investigation of the pH dependence of the sample during preparation on catalase-PBLH sample, it was demonstrated that the electrostatic force between the cantilever and the sample could be reduced as a result of charge cancellation at the catalase-PBLH interface (self-screening effect). We present 2D crystal images of catalase molecules acquired through AFM with molecular resolution, and demonstrate that sample preparation in which pH is optimized to induce the self-screening effect of surface charges is advantageous for AFM imaging of water-soluble protein molecules, because the electrostatic force can be controlled by changing the binding condition of the protein.

KW - Air-water interface

KW - Atomic force microscopy (AFM)

KW - Catalase

KW - Electrostatic interaction

KW - Poly(1-benzyl-L-histidine) (PBLH)

KW - Self-screening effect

KW - Two-dimensional crystal

KW - Water-soluble protein

UR - http://www.scopus.com/inward/record.url?scp=0030397047&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030397047&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0030397047

VL - 35

SP - 6233

EP - 6238

JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

SN - 0021-4922

IS - 12 A

ER -