Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical
The phenylalanine radical (Phe˙) has been proposed to mediate biological electron transport (ET) and exhibit long-lived electronic coherences following attosecond photoionization. However, the coupling of ultrafast structural reorganization to the oxidation/ionization of biomolecules such as phenyla...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2022
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/155544 |
| _version_ | 1826110699048271872 |
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| author | Muhammad Shafiq Mohd Yusof Siow, Jing Xuan Yang, Ningchen Chan, Wei Xin Loh, Zhi-Heng |
| author2 | School of Physical and Mathematical Sciences |
| author_facet | School of Physical and Mathematical Sciences Muhammad Shafiq Mohd Yusof Siow, Jing Xuan Yang, Ningchen Chan, Wei Xin Loh, Zhi-Heng |
| author_sort | Muhammad Shafiq Mohd Yusof |
| collection | NTU |
| description | The phenylalanine radical (Phe˙) has been proposed to mediate biological electron transport (ET) and exhibit long-lived electronic coherences following attosecond photoionization. However, the coupling of ultrafast structural reorganization to the oxidation/ionization of biomolecules such as phenylalanine remains unexplored. Moreover, studies of ET involving Phe˙ are hindered by its hitherto unobserved electronic spectrum. Here, we report the spectroscopic observation and coherent vibrational dynamics of aqueous Phe˙, prepared by sub-6 fs photodetachment of phenylalaninate anions. Sub-picosecond transient absorption spectroscopy reveals the ultraviolet absorption signature of Phe˙. Ultrafast structural reorganization drives coherent vibrational motion involving nine fundamental frequencies and one overtone. DFT calculations rationalize the absence of the decarboxylation reaction, a photodegradation pathway previously identified for Phe˙. Our findings guide the interpretation of future attosecond experiments aimed at elucidating coherent electron motion in photoionized aqueous biomolecules and pave way for the spectroscopic identification of Phe˙ in studies of biological ET. |
| first_indexed | 2024-10-01T02:38:46Z |
| format | Journal Article |
| id | ntu-10356/155544 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T02:38:46Z |
| publishDate | 2022 |
| record_format | dspace |
| spelling | ntu-10356/1555442023-02-28T20:00:38Z Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical Muhammad Shafiq Mohd Yusof Siow, Jing Xuan Yang, Ningchen Chan, Wei Xin Loh, Zhi-Heng School of Physical and Mathematical Sciences Science::Chemistry Electrons Phenylalanine The phenylalanine radical (Phe˙) has been proposed to mediate biological electron transport (ET) and exhibit long-lived electronic coherences following attosecond photoionization. However, the coupling of ultrafast structural reorganization to the oxidation/ionization of biomolecules such as phenylalanine remains unexplored. Moreover, studies of ET involving Phe˙ are hindered by its hitherto unobserved electronic spectrum. Here, we report the spectroscopic observation and coherent vibrational dynamics of aqueous Phe˙, prepared by sub-6 fs photodetachment of phenylalaninate anions. Sub-picosecond transient absorption spectroscopy reveals the ultraviolet absorption signature of Phe˙. Ultrafast structural reorganization drives coherent vibrational motion involving nine fundamental frequencies and one overtone. DFT calculations rationalize the absence of the decarboxylation reaction, a photodegradation pathway previously identified for Phe˙. Our findings guide the interpretation of future attosecond experiments aimed at elucidating coherent electron motion in photoionized aqueous biomolecules and pave way for the spectroscopic identification of Phe˙ in studies of biological ET. Accepted version 2022-03-03T05:41:29Z 2022-03-03T05:41:29Z 2022 Journal Article Muhammad Shafiq Mohd Yusof, Siow, J. X., Yang, N., Chan, W. X. & Loh, Z. (2022). Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical. Physical Chemistry Chemical Physics, 24(5), 2800-2812. https://dx.doi.org/10.1039/d1cp04326a 1463-9076 https://hdl.handle.net/10356/155544 10.1039/d1cp04326a 35048090 2-s2.0-85123969581 5 24 2800 2812 en RG1/20 RG105/17 MOE2014-T2-2-052 Physical Chemistry Chemical Physics © 2022 The Owner Societies. All rights reserved. This paper was published by Royal Society of Chemistry in Physical Chemistry Chemical Physics and is made available with permission of The Owner Societies. application/pdf |
| spellingShingle | Science::Chemistry Electrons Phenylalanine Muhammad Shafiq Mohd Yusof Siow, Jing Xuan Yang, Ningchen Chan, Wei Xin Loh, Zhi-Heng Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical |
| title | Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical |
| title_full | Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical |
| title_fullStr | Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical |
| title_full_unstemmed | Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical |
| title_short | Spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical |
| title_sort | spectroscopic observation and ultrafast coherent vibrational dynamics of the aqueous phenylalanine radical |
| topic | Science::Chemistry Electrons Phenylalanine |
| url | https://hdl.handle.net/10356/155544 |
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