Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red
The edible bird's nest (EBN) of the swiftlet Aerodramus fuciphagus, a mucin glycoprotein, is usually white in color, but there also exist the more desirable red or "blood" EBN. The basis of the red color has been a puzzle for a long time. Here, we show that the nitration of the tyrosy...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2020
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/142603 |
| _version_ | 1826129443677011968 |
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| author | Shim, Eric Kian-Shiun Lee, Soo-Ying |
| author2 | School of Physical and Mathematical Sciences |
| author_facet | School of Physical and Mathematical Sciences Shim, Eric Kian-Shiun Lee, Soo-Ying |
| author_sort | Shim, Eric Kian-Shiun |
| collection | NTU |
| description | The edible bird's nest (EBN) of the swiftlet Aerodramus fuciphagus, a mucin glycoprotein, is usually white in color, but there also exist the more desirable red or "blood" EBN. The basis of the red color has been a puzzle for a long time. Here, we show that the nitration of the tyrosyl residue to the 3-nitrotyrosyl (3-NTyr) residue in the glycoprotein is the cause of the red color. Evidence for the 3-NTyr residue comes from (a) the quantitative analysis of 3-NTyr in EBN by enzyme-linked immunosorbent assay, (b) the ultraviolet-visible absorption spectra of red EBN as a function of pH being similar to 3-nitrotyrosine (3-NT), (c) the change in the color of red EBN from yellow at low pH to red at high pH just like 3-NT, and (d) strong Raman nitro bands at 1330 cm-1 (symmetric -NO2 stretch) and 825 cm-1 (-NO2 scissoring bend) for red EBN. The high concentrations of nitrite and nitrate in red EBN are also explained. |
| first_indexed | 2024-10-01T07:40:42Z |
| format | Journal Article |
| id | ntu-10356/142603 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T07:40:42Z |
| publishDate | 2020 |
| record_format | dspace |
| spelling | ntu-10356/1426032020-06-25T04:41:01Z Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red Shim, Eric Kian-Shiun Lee, Soo-Ying School of Physical and Mathematical Sciences Science::Chemistry Red Edible Bird’s Nest Mucin Glycoprotein The edible bird's nest (EBN) of the swiftlet Aerodramus fuciphagus, a mucin glycoprotein, is usually white in color, but there also exist the more desirable red or "blood" EBN. The basis of the red color has been a puzzle for a long time. Here, we show that the nitration of the tyrosyl residue to the 3-nitrotyrosyl (3-NTyr) residue in the glycoprotein is the cause of the red color. Evidence for the 3-NTyr residue comes from (a) the quantitative analysis of 3-NTyr in EBN by enzyme-linked immunosorbent assay, (b) the ultraviolet-visible absorption spectra of red EBN as a function of pH being similar to 3-nitrotyrosine (3-NT), (c) the change in the color of red EBN from yellow at low pH to red at high pH just like 3-NT, and (d) strong Raman nitro bands at 1330 cm-1 (symmetric -NO2 stretch) and 825 cm-1 (-NO2 scissoring bend) for red EBN. The high concentrations of nitrite and nitrate in red EBN are also explained. 2020-06-25T04:41:01Z 2020-06-25T04:41:01Z 2018 Journal Article Shim, E. K.-S., & Lee, S.-Y. (2018). Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red. Journal of agricultural and food chemistry, 66(22), 5654-5662. doi:10.1021/acs.jafc.8b01619 0021-8561 https://hdl.handle.net/10356/142603 10.1021/acs.jafc.8b01619 29783841 2-s2.0-85047464028 22 66 5654 5662 en Journal of agricultural and food chemistry © 2018 American Chemical Society. All rights reserved. |
| spellingShingle | Science::Chemistry Red Edible Bird’s Nest Mucin Glycoprotein Shim, Eric Kian-Shiun Lee, Soo-Ying Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red |
| title | Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red |
| title_full | Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red |
| title_fullStr | Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red |
| title_full_unstemmed | Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red |
| title_short | Nitration of tyrosine in the mucin glycoprotein of edible bird's nest changes its color from white to red |
| title_sort | nitration of tyrosine in the mucin glycoprotein of edible bird s nest changes its color from white to red |
| topic | Science::Chemistry Red Edible Bird’s Nest Mucin Glycoprotein |
| url | https://hdl.handle.net/10356/142603 |
| work_keys_str_mv | AT shimerickianshiun nitrationoftyrosineinthemucinglycoproteinofediblebirdsnestchangesitscolorfromwhitetored AT leesooying nitrationoftyrosineinthemucinglycoproteinofediblebirdsnestchangesitscolorfromwhitetored |