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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.


FT-IR spectra of three different Al surfaces.Bare Al (black line) and Cn-AFP-coated Al (red line) substrates were compared with ABP-Cn-AFP-coated Al (blue line). Black and red lines were used as the control surfaces, there was the difference in FT-IR spectra especially at the amide region (~1654 cm−1), where the red line was rather similar to the blue line (ABP-Cn-AFPWT on Al).
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f4: FT-IR spectra of three different Al surfaces.Bare Al (black line) and Cn-AFP-coated Al (red line) substrates were compared with ABP-Cn-AFP-coated Al (blue line). Black and red lines were used as the control surfaces, there was the difference in FT-IR spectra especially at the amide region (~1654 cm−1), where the red line was rather similar to the blue line (ABP-Cn-AFPWT on 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)

FT-IR spectra of three different Al surfaces.Bare Al (black line) and Cn-AFP-coated Al (red line) substrates were compared with ABP-Cn-AFP-coated Al (blue line). Black and red lines were used as the control surfaces, there was the difference in FT-IR spectra especially at the amide region (~1654 cm−1), where the red line was rather similar to the blue line (ABP-Cn-AFPWT on Al).
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f4: FT-IR spectra of three different Al surfaces.Bare Al (black line) and Cn-AFP-coated Al (red line) substrates were compared with ABP-Cn-AFP-coated Al (blue line). Black and red lines were used as the control surfaces, there was the difference in FT-IR spectra especially at the amide region (~1654 cm−1), where the red line was rather similar to the blue line (ABP-Cn-AFPWT on 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.