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The Amylases of Insects
Alpha-amylases are major digestive enzymes that act in the first step of maltopolysaccharide digestion. In insects, these enzymes have long been studied for applied as well as purely scientific purposes. In many species, amylases are produced by multiple gene copies. Rare species are devoid of Amy g...
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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SAGE Publications
2018
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6176531/ https://www.ncbi.nlm.nih.gov/pubmed/30305796 http://dx.doi.org/10.1177/1179543318804783 |
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author | Da Lage, Jean-Luc |
author_facet | Da Lage, Jean-Luc |
author_sort | Da Lage, Jean-Luc |
collection | PubMed |
description | Alpha-amylases are major digestive enzymes that act in the first step of maltopolysaccharide digestion. In insects, these enzymes have long been studied for applied as well as purely scientific purposes. In many species, amylases are produced by multiple gene copies. Rare species are devoid of Amy gene. They are predominantly secreted in the midgut but salivary expression is also frequent, with extraoral activity. Enzymological parameters are quite variable among insects, with visible trends according to phylogeny: Coleopteran amylases have acidic optimum activity, whereas dipteran amylases have neutral preference and lepidopteran ones have clear alkaline preference. The enzyme structure shows interesting variations shaped by evolutionary convergences, such as the recurrent loss of a loop involved in substrate handling. Many works have focused on the action of plant amylase inhibitors on pest insect amylases, in the frame of crop protection by transgenesis. It appears that sensitivity or resistance to inhibitors is finely tuned and very specific and that amylases and their inhibitors have coevolved. The multicopy feature of insect amylases appears to allow tissue-specific or stage-specific regulation, but also to broaden enzymological abilities, such as pH range, and to overcome plant inhibitory defenses. |
format | Online Article Text |
id | pubmed-6176531 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2018 |
publisher | SAGE Publications |
record_format | MEDLINE/PubMed |
spelling | pubmed-61765312018-10-10 The Amylases of Insects Da Lage, Jean-Luc Int J Insect Sci Mini-Review Alpha-amylases are major digestive enzymes that act in the first step of maltopolysaccharide digestion. In insects, these enzymes have long been studied for applied as well as purely scientific purposes. In many species, amylases are produced by multiple gene copies. Rare species are devoid of Amy gene. They are predominantly secreted in the midgut but salivary expression is also frequent, with extraoral activity. Enzymological parameters are quite variable among insects, with visible trends according to phylogeny: Coleopteran amylases have acidic optimum activity, whereas dipteran amylases have neutral preference and lepidopteran ones have clear alkaline preference. The enzyme structure shows interesting variations shaped by evolutionary convergences, such as the recurrent loss of a loop involved in substrate handling. Many works have focused on the action of plant amylase inhibitors on pest insect amylases, in the frame of crop protection by transgenesis. It appears that sensitivity or resistance to inhibitors is finely tuned and very specific and that amylases and their inhibitors have coevolved. The multicopy feature of insect amylases appears to allow tissue-specific or stage-specific regulation, but also to broaden enzymological abilities, such as pH range, and to overcome plant inhibitory defenses. SAGE Publications 2018-10-08 /pmc/articles/PMC6176531/ /pubmed/30305796 http://dx.doi.org/10.1177/1179543318804783 Text en © The Author(s) 2018 http://www.creativecommons.org/licenses/by-nc/4.0/ This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (http://www.creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage). |
spellingShingle | Mini-Review Da Lage, Jean-Luc The Amylases of Insects |
title | The Amylases of Insects |
title_full | The Amylases of Insects |
title_fullStr | The Amylases of Insects |
title_full_unstemmed | The Amylases of Insects |
title_short | The Amylases of Insects |
title_sort | amylases of insects |
topic | Mini-Review |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6176531/ https://www.ncbi.nlm.nih.gov/pubmed/30305796 http://dx.doi.org/10.1177/1179543318804783 |
work_keys_str_mv | AT dalagejeanluc theamylasesofinsects AT dalagejeanluc amylasesofinsects |