Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated Descriptors
New quantitative structure−activity relationship (QSAR) models for bitter peptides were built with integrated amino acid descriptors. Datasets contained 48 dipeptides, 52 tripeptides and 23 tetrapeptides with their reported bitter taste thresholds. Independent variables consisted of 14 ami...
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| Format: | Article |
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MDPI AG
2019-08-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/24/15/2846 |
| _version_ | 1818284724891680768 |
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| author | Biyang Xu Hau Yin Chung |
| author_facet | Biyang Xu Hau Yin Chung |
| author_sort | Biyang Xu |
| collection | DOAJ |
| description | New quantitative structure−activity relationship (QSAR) models for bitter peptides were built with integrated amino acid descriptors. Datasets contained 48 dipeptides, 52 tripeptides and 23 tetrapeptides with their reported bitter taste thresholds. Independent variables consisted of 14 amino acid descriptor sets. A bootstrapping soft shrinkage approach was utilized for variable selection. The importance of a variable was evaluated by both variable selecting frequency and standardized regression coefficient. Results indicated model qualities for di-, tri- and tetrapeptides with R<sup>2</sup> and Q<sup>2</sup> at 0.950 ± 0.002, 0.941 ± 0.001; 0.770 ± 0.006, 0.742 ± 0.004; and 0.972 ± 0.002, 0.956 ± 0.002, respectively. The hydrophobic C-terminal amino acid was the key determinant for bitterness in dipeptides, followed by the contribution of bulky hydrophobic N-terminal amino acids. For tripeptides, hydrophobicity of C-terminal amino acids and the electronic properties of the amino acids at the second position were important. For tetrapeptides, bulky hydrophobic amino acids at N-terminus, hydrophobicity and partial specific volume of amino acids at the second position, and the electronic properties of amino acids of the remaining two positions were critical. In summary, this study not only constructs reliable models for predicting the bitterness in different groups of peptides, but also facilitates better understanding of their structure-bitterness relationships and provides insights for their future studies. |
| first_indexed | 2024-12-13T00:57:22Z |
| format | Article |
| id | doaj.art-9f7c2c2c826c47c7b97503326529bfb7 |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-12-13T00:57:22Z |
| publishDate | 2019-08-01 |
| publisher | MDPI AG |
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| series | Molecules |
| spelling | doaj.art-9f7c2c2c826c47c7b97503326529bfb72022-12-22T00:04:47ZengMDPI AGMolecules1420-30492019-08-012415284610.3390/molecules24152846molecules24152846Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated DescriptorsBiyang Xu0Hau Yin Chung1Food and Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, ChinaFood and Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, ChinaNew quantitative structure−activity relationship (QSAR) models for bitter peptides were built with integrated amino acid descriptors. Datasets contained 48 dipeptides, 52 tripeptides and 23 tetrapeptides with their reported bitter taste thresholds. Independent variables consisted of 14 amino acid descriptor sets. A bootstrapping soft shrinkage approach was utilized for variable selection. The importance of a variable was evaluated by both variable selecting frequency and standardized regression coefficient. Results indicated model qualities for di-, tri- and tetrapeptides with R<sup>2</sup> and Q<sup>2</sup> at 0.950 ± 0.002, 0.941 ± 0.001; 0.770 ± 0.006, 0.742 ± 0.004; and 0.972 ± 0.002, 0.956 ± 0.002, respectively. The hydrophobic C-terminal amino acid was the key determinant for bitterness in dipeptides, followed by the contribution of bulky hydrophobic N-terminal amino acids. For tripeptides, hydrophobicity of C-terminal amino acids and the electronic properties of the amino acids at the second position were important. For tetrapeptides, bulky hydrophobic amino acids at N-terminus, hydrophobicity and partial specific volume of amino acids at the second position, and the electronic properties of amino acids of the remaining two positions were critical. In summary, this study not only constructs reliable models for predicting the bitterness in different groups of peptides, but also facilitates better understanding of their structure-bitterness relationships and provides insights for their future studies.https://www.mdpi.com/1420-3049/24/15/2846QSARbitterpeptidesamino acid descriptors |
| spellingShingle | Biyang Xu Hau Yin Chung Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated Descriptors Molecules QSAR bitter peptides amino acid descriptors |
| title | Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated Descriptors |
| title_full | Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated Descriptors |
| title_fullStr | Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated Descriptors |
| title_full_unstemmed | Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated Descriptors |
| title_short | Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated Descriptors |
| title_sort | quantitative structure activity relationship study of bitter di tri and tetrapeptides using integrated descriptors |
| topic | QSAR bitter peptides amino acid descriptors |
| url | https://www.mdpi.com/1420-3049/24/15/2846 |
| work_keys_str_mv | AT biyangxu quantitativestructureactivityrelationshipstudyofbitterditriandtetrapeptidesusingintegrateddescriptors AT hauyinchung quantitativestructureactivityrelationshipstudyofbitterditriandtetrapeptidesusingintegrateddescriptors |