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Creating Anti-icing Surfaces via the Direct Immobilization of Antifreeze Proteins on Aluminum.

Gwak Y, Park JI, Kim M, Kim HS, Kwon MJ, Oh SJ, Kim YP, Jin E - Sci Rep (2015)

Bottom Line: The ABP bound well to the Al and did not considerably change the functional properties of AFP.Additional trehalose coating of Cn-AFP-Al considerably delayed AFP denaturation on the Al without affecting its antifreeze activity.This metal surface-coating method using trehalose-fortified AFP can be applied to other metals important in the aircraft and cold storage fields where anti-icing materials are critical.

View Article: PubMed Central - PubMed

Affiliation: Department of Life Science, Research Institute for Natural Science, Hanyang University, Seoul, 133-791, South Korea.

ABSTRACT
Cryoprotectants such as antifreeze proteins (AFPs) and sugar molecules may provide a solution for icing problems. These anti-icing substances protect cells and tissues from freezing by inhibiting ice formation. In this study, we developed a method for coating an industrial metal material (aluminum, Al) with AFP from the Antarctic marine diatom, Chaetoceros neogracile (Cn-AFP), to prevent or delay ice formation. To coat Al with Cn-AFP, we used an Al-binding peptide (ABP) as a conjugator and fused it with Cn-AFP. The ABP bound well to the Al and did not considerably change the functional properties of AFP. Cn-AFP-coated Al (Cn-AFP-Al) showed a sufficiently low supercooling point. Additional trehalose coating of Cn-AFP-Al considerably delayed AFP denaturation on the Al without affecting its antifreeze activity. This metal surface-coating method using trehalose-fortified AFP can be applied to other metals important in the aircraft and cold storage fields where anti-icing materials are critical.

No MeSH data available.


Coating of the Al substrate with Cn-AFP.(A) Scheme of Al coating with Cn-AFP. The blue corresponds to the Al-binding peptide. (B) Scheme of the tetramethylbenzidine (TMB) assay. TMB is a soluble colorimetric substrate for horseradish peroxidase (HRP). In the presence of HRP, TMB and peroxide present in the substrate solution react to produce a blue product. The color intensity is proportional to the HRP activity. (C) Confirmation of ABP-Cn-AFP binding to an Al substrate using the TMB assay. Al alone or after “coating” with Cn-AFP (without ABP) did not result in blue coloration. In the presence of ABP-Cn-AFP-coated Al, the solution color changed to blue, which indicated ABP-Cn-AFP binding to the Al.
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f3: Coating of the Al substrate with Cn-AFP.(A) Scheme of Al coating with Cn-AFP. The blue corresponds to the Al-binding peptide. (B) Scheme of the tetramethylbenzidine (TMB) assay. TMB is a soluble colorimetric substrate for horseradish peroxidase (HRP). In the presence of HRP, TMB and peroxide present in the substrate solution react to produce a blue product. The color intensity is proportional to the HRP activity. (C) Confirmation of ABP-Cn-AFP binding to an Al substrate using the TMB assay. Al alone or after “coating” with Cn-AFP (without ABP) did not result in blue coloration. In the presence of ABP-Cn-AFP-coated Al, the solution color changed to blue, which indicated ABP-Cn-AFP binding to the Al.

Mentions: To determine whether ABP-Cn-AFP can be effectively immobilized on the Al surface, a simple coating method was developed based on dipping an Al plate into a reaction solution containing Cn-AFPWT or ABP-Cn-AFPWT (Fig. 3A). The immobilization of AFP on Al was monitored using a colorimetric assay, where Cn-AFPWT or ABP-Cn-AFPWT expressed with His6-tag at its N-terminus was detected by Ni (II)/horseradish peroxidase (HRP), which produced a strong blue coloration because of HRP-catalyzed oxidation of its substrate (tetramethylbenzidine, TMB) (Fig. 3B). As shown in Fig. 3C, a strong blue color was significantly observed on the Al surface coated with ABP-Cn-AFPWT, while bare Al and ABP-free Cn-AFPWT produced no coloration. To further verify the ABP-mediated binding of Cn-AFP to Al, three surfaces (bare Al, Cn-AFPWT immobilized on Al, and ABP-Cn-AFPWT immobilized on Al) were characterized via Fourier transform-infrared (FT-IR) spectroscopy (Fig. 4). While the Al−OH regions were commonly observed for all three tested surfaces, as indicated by three bands in the FT-IR spectra at ~955, ~1033, and 3535–3580 cm−1, the intensities of protein-specific peaks corresponding to N-H stretching (3700–3500 cm−1), amide C = O stretching (1690–1630 cm−1), and amide C-N stretching (1000–1250 cm−1) were higher for ABP-Cn-AFPWT immobilized on the Al surface (blue line in Fig. 3) than those for the other two surfaces (black and red lines in Fig. 4). However, the red line (AFP without ABP tag) also showed an amide bond peak, which is presumed to be denatured after surface adsorption, taking consideration into Fig. 3. Taken together, these results indicate that ABP-fused Cn-AFP effectively binds to the Al surface via ABP without denaturation.


Creating Anti-icing Surfaces via the Direct Immobilization of Antifreeze Proteins on Aluminum.

Gwak Y, Park JI, Kim M, Kim HS, Kwon MJ, Oh SJ, Kim YP, Jin E - Sci Rep (2015)

Coating of the Al substrate with Cn-AFP.(A) Scheme of Al coating with Cn-AFP. The blue corresponds to the Al-binding peptide. (B) Scheme of the tetramethylbenzidine (TMB) assay. TMB is a soluble colorimetric substrate for horseradish peroxidase (HRP). In the presence of HRP, TMB and peroxide present in the substrate solution react to produce a blue product. The color intensity is proportional to the HRP activity. (C) Confirmation of ABP-Cn-AFP binding to an Al substrate using the TMB assay. Al alone or after “coating” with Cn-AFP (without ABP) did not result in blue coloration. In the presence of ABP-Cn-AFP-coated Al, the solution color changed to blue, which indicated ABP-Cn-AFP binding to the Al.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4495550&req=5

f3: Coating of the Al substrate with Cn-AFP.(A) Scheme of Al coating with Cn-AFP. The blue corresponds to the Al-binding peptide. (B) Scheme of the tetramethylbenzidine (TMB) assay. TMB is a soluble colorimetric substrate for horseradish peroxidase (HRP). In the presence of HRP, TMB and peroxide present in the substrate solution react to produce a blue product. The color intensity is proportional to the HRP activity. (C) Confirmation of ABP-Cn-AFP binding to an Al substrate using the TMB assay. Al alone or after “coating” with Cn-AFP (without ABP) did not result in blue coloration. In the presence of ABP-Cn-AFP-coated Al, the solution color changed to blue, which indicated ABP-Cn-AFP binding to the Al.
Mentions: To determine whether ABP-Cn-AFP can be effectively immobilized on the Al surface, a simple coating method was developed based on dipping an Al plate into a reaction solution containing Cn-AFPWT or ABP-Cn-AFPWT (Fig. 3A). The immobilization of AFP on Al was monitored using a colorimetric assay, where Cn-AFPWT or ABP-Cn-AFPWT expressed with His6-tag at its N-terminus was detected by Ni (II)/horseradish peroxidase (HRP), which produced a strong blue coloration because of HRP-catalyzed oxidation of its substrate (tetramethylbenzidine, TMB) (Fig. 3B). As shown in Fig. 3C, a strong blue color was significantly observed on the Al surface coated with ABP-Cn-AFPWT, while bare Al and ABP-free Cn-AFPWT produced no coloration. To further verify the ABP-mediated binding of Cn-AFP to Al, three surfaces (bare Al, Cn-AFPWT immobilized on Al, and ABP-Cn-AFPWT immobilized on Al) were characterized via Fourier transform-infrared (FT-IR) spectroscopy (Fig. 4). While the Al−OH regions were commonly observed for all three tested surfaces, as indicated by three bands in the FT-IR spectra at ~955, ~1033, and 3535–3580 cm−1, the intensities of protein-specific peaks corresponding to N-H stretching (3700–3500 cm−1), amide C = O stretching (1690–1630 cm−1), and amide C-N stretching (1000–1250 cm−1) were higher for ABP-Cn-AFPWT immobilized on the Al surface (blue line in Fig. 3) than those for the other two surfaces (black and red lines in Fig. 4). However, the red line (AFP without ABP tag) also showed an amide bond peak, which is presumed to be denatured after surface adsorption, taking consideration into Fig. 3. Taken together, these results indicate that ABP-fused Cn-AFP effectively binds to the Al surface via ABP without denaturation.

Bottom Line: The ABP bound well to the Al and did not considerably change the functional properties of AFP.Additional trehalose coating of Cn-AFP-Al considerably delayed AFP denaturation on the Al without affecting its antifreeze activity.This metal surface-coating method using trehalose-fortified AFP can be applied to other metals important in the aircraft and cold storage fields where anti-icing materials are critical.

View Article: PubMed Central - PubMed

Affiliation: Department of Life Science, Research Institute for Natural Science, Hanyang University, Seoul, 133-791, South Korea.

ABSTRACT
Cryoprotectants such as antifreeze proteins (AFPs) and sugar molecules may provide a solution for icing problems. These anti-icing substances protect cells and tissues from freezing by inhibiting ice formation. In this study, we developed a method for coating an industrial metal material (aluminum, Al) with AFP from the Antarctic marine diatom, Chaetoceros neogracile (Cn-AFP), to prevent or delay ice formation. To coat Al with Cn-AFP, we used an Al-binding peptide (ABP) as a conjugator and fused it with Cn-AFP. The ABP bound well to the Al and did not considerably change the functional properties of AFP. Cn-AFP-coated Al (Cn-AFP-Al) showed a sufficiently low supercooling point. Additional trehalose coating of Cn-AFP-Al considerably delayed AFP denaturation on the Al without affecting its antifreeze activity. This metal surface-coating method using trehalose-fortified AFP can be applied to other metals important in the aircraft and cold storage fields where anti-icing materials are critical.

No MeSH data available.