Enhancement of Bacillus thuringiensis Cry1Ab and Cry1Fa Toxicity to Spodoptera frugiperda by Domain III Mutations Indicates There Are Two Limiting Steps in Toxicity as Defined by Receptor Binding and Protein Stability
Cry1Ab and Cry1Fa toxins are environmentally safe insecticides that control important insect pests. is an important maize pest that shows low susceptibility to Cry1A toxins, in contrast to Cry1Fa, which is highly active against this pest and is used in transgenic maize for control. The β16 region fr...
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creator | Gómez, Isabel Ocelotl, Josue Sánchez, Jorge Lima, Christina Martins, Erica Rosales-Juárez, Anayeli Aguilar-Medel, Sotero Abad, André Dong, Hua Monnerat, Rose Peña, Guadalupe Zhang, Jie Nelson, Mark Wu, Gusui Bravo, Alejandra Soberón, Mario |
description | Cry1Ab and Cry1Fa toxins are environmentally safe insecticides that control important insect pests.
is an important maize pest that shows low susceptibility to Cry1A toxins, in contrast to Cry1Fa, which is highly active against this pest and is used in transgenic maize for
control. The β16 region from domain III of Cry1Ab has been shown to be involved in interactions with receptors such as alkaline phosphatase (ALP) or aminopeptidase (APN) in different lepidopteran insects. Alanine-scanning mutagenesis of amino acids of Cry1Ab β16 (
STLRVN
) revealed that certain β16 mutations, such as N514A, resulted in increased toxicity of Cry1Ab for
without affecting the toxicity for other lepidopteran larvae, such as
larvae. Exhaustive mutagenesis of N514 was performed, showing that the Cry1Ab N514F, N514H, N514K, N514L, N514Q, and N514S mutations increased the toxicity toward
A corresponding mutation was constructed in Cry1Fa (N507A). Toxicity assays of wild-type and mutant toxins (Cry1Ab, Cry1AbN514A, Cry1AbN514F, Cry1Fa, and Cry1FaN507A) against four
populations from Mexico and one from Brazil revealed that Cry1AbN514A and Cry1FaN507A consistently showed 3- to 18-fold increased toxicity against four of five
populations. In contrast, Cry1AbN514F showed increased toxicity in only two of the
populations analyzed. The mutants Cry1AbN514A and Cry1AbN514F showed greater stability to midgut protease treatment. In addition, binding analysis of the Cry1Ab mutants showed that the increased toxicity correlated with increased binding to brush border membrane vesicles and increased binding affinity for
ALP, APN, and cadherin receptors.
is the main maize pest in South and North America and also is an invasive pest in different African countries. However, it is poorly controlled by
Cry1A toxins expressed in transgenic crops, which effectively control other lepidopteran pests. In contrast, maize expressing Cry1Fa is effective in the control of
, although its effectiveness is being lost due to resistance evolution. Some of the Cry1Ab domain III mutants characterized here show enhanced toxicity for
without loss of toxicity to
Thus, these Cry1Ab mutants could provide useful engineered toxins that, along with other Cry toxins, would be useful for developing transgenic maize expressing stacked proteins for the effective control of
and other lepidopteran pests in the field. |
doi_str_mv | 10.1128/AEM.01393-18 |
format | Article |
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is an important maize pest that shows low susceptibility to Cry1A toxins, in contrast to Cry1Fa, which is highly active against this pest and is used in transgenic maize for
control. The β16 region from domain III of Cry1Ab has been shown to be involved in interactions with receptors such as alkaline phosphatase (ALP) or aminopeptidase (APN) in different lepidopteran insects. Alanine-scanning mutagenesis of amino acids of Cry1Ab β16 (
STLRVN
) revealed that certain β16 mutations, such as N514A, resulted in increased toxicity of Cry1Ab for
without affecting the toxicity for other lepidopteran larvae, such as
larvae. Exhaustive mutagenesis of N514 was performed, showing that the Cry1Ab N514F, N514H, N514K, N514L, N514Q, and N514S mutations increased the toxicity toward
A corresponding mutation was constructed in Cry1Fa (N507A). Toxicity assays of wild-type and mutant toxins (Cry1Ab, Cry1AbN514A, Cry1AbN514F, Cry1Fa, and Cry1FaN507A) against four
populations from Mexico and one from Brazil revealed that Cry1AbN514A and Cry1FaN507A consistently showed 3- to 18-fold increased toxicity against four of five
populations. In contrast, Cry1AbN514F showed increased toxicity in only two of the
populations analyzed. The mutants Cry1AbN514A and Cry1AbN514F showed greater stability to midgut protease treatment. In addition, binding analysis of the Cry1Ab mutants showed that the increased toxicity correlated with increased binding to brush border membrane vesicles and increased binding affinity for
ALP, APN, and cadherin receptors.
is the main maize pest in South and North America and also is an invasive pest in different African countries. However, it is poorly controlled by
Cry1A toxins expressed in transgenic crops, which effectively control other lepidopteran pests. In contrast, maize expressing Cry1Fa is effective in the control of
, although its effectiveness is being lost due to resistance evolution. Some of the Cry1Ab domain III mutants characterized here show enhanced toxicity for
without loss of toxicity to
Thus, these Cry1Ab mutants could provide useful engineered toxins that, along with other Cry toxins, would be useful for developing transgenic maize expressing stacked proteins for the effective control of
and other lepidopteran pests in the field.</description><identifier>ISSN: 0099-2240</identifier><identifier>EISSN: 1098-5336</identifier><identifier>DOI: 10.1128/AEM.01393-18</identifier><identifier>PMID: 30097439</identifier><language>eng</language><publisher>United States: American Society for Microbiology</publisher><subject>Alanine ; Alkaline phosphatase ; Amino acids ; Aminopeptidase ; Bacillus thuringiensis ; Binding ; Binding sites ; Cadherin receptors ; Cadherins ; Corn ; Gram-positive bacteria ; Insecticides ; Insects ; Invertebrate Microbiology ; Larvae ; Membrane vesicles ; Midgut ; Mutagenesis ; Mutants ; Mutation ; Pest control ; Pests ; Populations ; Proteins ; Receptors ; Scanning mutagenesis ; Spodoptera frugiperda ; Stability analysis ; Toxicity ; Toxins</subject><ispartof>Applied and environmental microbiology, 2018-10, Vol.84 (20)</ispartof><rights>Copyright © 2018 American Society for Microbiology.</rights><rights>Copyright American Society for Microbiology Oct 2018</rights><rights>Copyright © 2018 American Society for Microbiology. 2018 American Society for Microbiology</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c412t-d318bed0ea1f05f5f329e56ed6990fc92d59b62619b0684711cc8010838fede03</citedby><cites>FETCH-LOGICAL-c412t-d318bed0ea1f05f5f329e56ed6990fc92d59b62619b0684711cc8010838fede03</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC6182889/pdf/$$EPDF$$P50$$Gpubmedcentral$$H</linktopdf><linktohtml>$$Uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC6182889/$$EHTML$$P50$$Gpubmedcentral$$H</linktohtml><link.rule.ids>230,314,723,776,780,881,3175,27901,27902,53766,53768</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/30097439$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Gómez, Isabel</creatorcontrib><creatorcontrib>Ocelotl, Josue</creatorcontrib><creatorcontrib>Sánchez, Jorge</creatorcontrib><creatorcontrib>Lima, Christina</creatorcontrib><creatorcontrib>Martins, Erica</creatorcontrib><creatorcontrib>Rosales-Juárez, Anayeli</creatorcontrib><creatorcontrib>Aguilar-Medel, Sotero</creatorcontrib><creatorcontrib>Abad, André</creatorcontrib><creatorcontrib>Dong, Hua</creatorcontrib><creatorcontrib>Monnerat, Rose</creatorcontrib><creatorcontrib>Peña, Guadalupe</creatorcontrib><creatorcontrib>Zhang, Jie</creatorcontrib><creatorcontrib>Nelson, Mark</creatorcontrib><creatorcontrib>Wu, Gusui</creatorcontrib><creatorcontrib>Bravo, Alejandra</creatorcontrib><creatorcontrib>Soberón, Mario</creatorcontrib><title>Enhancement of Bacillus thuringiensis Cry1Ab and Cry1Fa Toxicity to Spodoptera frugiperda by Domain III Mutations Indicates There Are Two Limiting Steps in Toxicity as Defined by Receptor Binding and Protein Stability</title><title>Applied and environmental microbiology</title><addtitle>Appl Environ Microbiol</addtitle><description>Cry1Ab and Cry1Fa toxins are environmentally safe insecticides that control important insect pests.
is an important maize pest that shows low susceptibility to Cry1A toxins, in contrast to Cry1Fa, which is highly active against this pest and is used in transgenic maize for
control. The β16 region from domain III of Cry1Ab has been shown to be involved in interactions with receptors such as alkaline phosphatase (ALP) or aminopeptidase (APN) in different lepidopteran insects. Alanine-scanning mutagenesis of amino acids of Cry1Ab β16 (
STLRVN
) revealed that certain β16 mutations, such as N514A, resulted in increased toxicity of Cry1Ab for
without affecting the toxicity for other lepidopteran larvae, such as
larvae. Exhaustive mutagenesis of N514 was performed, showing that the Cry1Ab N514F, N514H, N514K, N514L, N514Q, and N514S mutations increased the toxicity toward
A corresponding mutation was constructed in Cry1Fa (N507A). Toxicity assays of wild-type and mutant toxins (Cry1Ab, Cry1AbN514A, Cry1AbN514F, Cry1Fa, and Cry1FaN507A) against four
populations from Mexico and one from Brazil revealed that Cry1AbN514A and Cry1FaN507A consistently showed 3- to 18-fold increased toxicity against four of five
populations. In contrast, Cry1AbN514F showed increased toxicity in only two of the
populations analyzed. The mutants Cry1AbN514A and Cry1AbN514F showed greater stability to midgut protease treatment. In addition, binding analysis of the Cry1Ab mutants showed that the increased toxicity correlated with increased binding to brush border membrane vesicles and increased binding affinity for
ALP, APN, and cadherin receptors.
is the main maize pest in South and North America and also is an invasive pest in different African countries. However, it is poorly controlled by
Cry1A toxins expressed in transgenic crops, which effectively control other lepidopteran pests. In contrast, maize expressing Cry1Fa is effective in the control of
, although its effectiveness is being lost due to resistance evolution. Some of the Cry1Ab domain III mutants characterized here show enhanced toxicity for
without loss of toxicity to
Thus, these Cry1Ab mutants could provide useful engineered toxins that, along with other Cry toxins, would be useful for developing transgenic maize expressing stacked proteins for the effective control of
and other lepidopteran pests in the field.</description><subject>Alanine</subject><subject>Alkaline phosphatase</subject><subject>Amino acids</subject><subject>Aminopeptidase</subject><subject>Bacillus thuringiensis</subject><subject>Binding</subject><subject>Binding sites</subject><subject>Cadherin receptors</subject><subject>Cadherins</subject><subject>Corn</subject><subject>Gram-positive bacteria</subject><subject>Insecticides</subject><subject>Insects</subject><subject>Invertebrate Microbiology</subject><subject>Larvae</subject><subject>Membrane vesicles</subject><subject>Midgut</subject><subject>Mutagenesis</subject><subject>Mutants</subject><subject>Mutation</subject><subject>Pest control</subject><subject>Pests</subject><subject>Populations</subject><subject>Proteins</subject><subject>Receptors</subject><subject>Scanning mutagenesis</subject><subject>Spodoptera frugiperda</subject><subject>Stability analysis</subject><subject>Toxicity</subject><subject>Toxins</subject><issn>0099-2240</issn><issn>1098-5336</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2018</creationdate><recordtype>article</recordtype><recordid>eNpVUk1v0zAYjhCIdYMbZ2SJKxn-aFL7gtR1HVTqBKLlbDn2m9ZTYgfbgfWn8m9wt1HBwbKl9_nS66co3hB8SQjlH-bL20tMmGAl4c-KCcGClxVj9fNigrEQJaVTfFacx3iHMZ7imr8szliezKZMTIrfS7dXTkMPLiHfoiulbdeNEaX9GKzbWXDRRrQIBzJvkHLm4Xmj0NbfW23TASWPNoM3fkgQFGrDuLMDBKNQc0DXvlfWodVqhW7HpJL1LqKVM1arBBFt9xAAzfPZ_vJobXubsiXaJBgiyryTh4roGlrrwBxVv4GGIfmArmyWyoRjrK_BJ8icTVKN7TLpVfGiVV2E10_3RfH9ZrldfC7XXz6tFvN1qaeEptIwwhswGBRpcdVWLaMCqhpMLQRutaCmEk1NayKavLvpjBCtOSaYM96CAcwuio-PusPY9GB0XmRQnRyC7VU4SK-s_H_i7F7u_E9ZE045F1ng3ZNA8D9GiEne-TG4nFlSQqsZZRVnGfX-EaWDjzFAe3IgWB6LIHMR5EMRJOEZ_vbfVCfw359nfwBGDrKA</recordid><startdate>20181001</startdate><enddate>20181001</enddate><creator>Gómez, Isabel</creator><creator>Ocelotl, Josue</creator><creator>Sánchez, Jorge</creator><creator>Lima, Christina</creator><creator>Martins, Erica</creator><creator>Rosales-Juárez, Anayeli</creator><creator>Aguilar-Medel, Sotero</creator><creator>Abad, André</creator><creator>Dong, Hua</creator><creator>Monnerat, Rose</creator><creator>Peña, Guadalupe</creator><creator>Zhang, Jie</creator><creator>Nelson, Mark</creator><creator>Wu, Gusui</creator><creator>Bravo, Alejandra</creator><creator>Soberón, Mario</creator><general>American Society for Microbiology</general><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7QL</scope><scope>7QO</scope><scope>7SN</scope><scope>7SS</scope><scope>7ST</scope><scope>7T7</scope><scope>7TM</scope><scope>7U9</scope><scope>8FD</scope><scope>C1K</scope><scope>FR3</scope><scope>H94</scope><scope>M7N</scope><scope>P64</scope><scope>RC3</scope><scope>SOI</scope><scope>5PM</scope></search><sort><creationdate>20181001</creationdate><title>Enhancement of Bacillus thuringiensis Cry1Ab and Cry1Fa Toxicity to Spodoptera frugiperda by Domain III Mutations Indicates There Are Two Limiting Steps in Toxicity as Defined by Receptor Binding and Protein Stability</title><author>Gómez, Isabel ; Ocelotl, Josue ; Sánchez, Jorge ; Lima, Christina ; Martins, Erica ; Rosales-Juárez, Anayeli ; Aguilar-Medel, Sotero ; Abad, André ; Dong, Hua ; Monnerat, Rose ; Peña, Guadalupe ; Zhang, Jie ; Nelson, Mark ; Wu, Gusui ; Bravo, Alejandra ; Soberón, Mario</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c412t-d318bed0ea1f05f5f329e56ed6990fc92d59b62619b0684711cc8010838fede03</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2018</creationdate><topic>Alanine</topic><topic>Alkaline phosphatase</topic><topic>Amino acids</topic><topic>Aminopeptidase</topic><topic>Bacillus thuringiensis</topic><topic>Binding</topic><topic>Binding sites</topic><topic>Cadherin receptors</topic><topic>Cadherins</topic><topic>Corn</topic><topic>Gram-positive bacteria</topic><topic>Insecticides</topic><topic>Insects</topic><topic>Invertebrate Microbiology</topic><topic>Larvae</topic><topic>Membrane vesicles</topic><topic>Midgut</topic><topic>Mutagenesis</topic><topic>Mutants</topic><topic>Mutation</topic><topic>Pest control</topic><topic>Pests</topic><topic>Populations</topic><topic>Proteins</topic><topic>Receptors</topic><topic>Scanning mutagenesis</topic><topic>Spodoptera frugiperda</topic><topic>Stability analysis</topic><topic>Toxicity</topic><topic>Toxins</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Gómez, Isabel</creatorcontrib><creatorcontrib>Ocelotl, Josue</creatorcontrib><creatorcontrib>Sánchez, Jorge</creatorcontrib><creatorcontrib>Lima, Christina</creatorcontrib><creatorcontrib>Martins, Erica</creatorcontrib><creatorcontrib>Rosales-Juárez, Anayeli</creatorcontrib><creatorcontrib>Aguilar-Medel, Sotero</creatorcontrib><creatorcontrib>Abad, André</creatorcontrib><creatorcontrib>Dong, Hua</creatorcontrib><creatorcontrib>Monnerat, Rose</creatorcontrib><creatorcontrib>Peña, Guadalupe</creatorcontrib><creatorcontrib>Zhang, Jie</creatorcontrib><creatorcontrib>Nelson, Mark</creatorcontrib><creatorcontrib>Wu, Gusui</creatorcontrib><creatorcontrib>Bravo, Alejandra</creatorcontrib><creatorcontrib>Soberón, Mario</creatorcontrib><collection>PubMed</collection><collection>CrossRef</collection><collection>Bacteriology Abstracts (Microbiology B)</collection><collection>Biotechnology Research Abstracts</collection><collection>Ecology Abstracts</collection><collection>Entomology Abstracts (Full archive)</collection><collection>Environment Abstracts</collection><collection>Industrial and Applied Microbiology Abstracts (Microbiology A)</collection><collection>Nucleic Acids Abstracts</collection><collection>Virology and AIDS Abstracts</collection><collection>Technology Research Database</collection><collection>Environmental Sciences and Pollution Management</collection><collection>Engineering Research Database</collection><collection>AIDS and Cancer Research Abstracts</collection><collection>Algology Mycology and Protozoology Abstracts (Microbiology C)</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>Genetics Abstracts</collection><collection>Environment Abstracts</collection><collection>PubMed Central (Full Participant titles)</collection><jtitle>Applied and environmental microbiology</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Gómez, Isabel</au><au>Ocelotl, Josue</au><au>Sánchez, Jorge</au><au>Lima, Christina</au><au>Martins, Erica</au><au>Rosales-Juárez, Anayeli</au><au>Aguilar-Medel, Sotero</au><au>Abad, André</au><au>Dong, Hua</au><au>Monnerat, Rose</au><au>Peña, Guadalupe</au><au>Zhang, Jie</au><au>Nelson, Mark</au><au>Wu, Gusui</au><au>Bravo, Alejandra</au><au>Soberón, Mario</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Enhancement of Bacillus thuringiensis Cry1Ab and Cry1Fa Toxicity to Spodoptera frugiperda by Domain III Mutations Indicates There Are Two Limiting Steps in Toxicity as Defined by Receptor Binding and Protein Stability</atitle><jtitle>Applied and environmental microbiology</jtitle><addtitle>Appl Environ Microbiol</addtitle><date>2018-10-01</date><risdate>2018</risdate><volume>84</volume><issue>20</issue><issn>0099-2240</issn><eissn>1098-5336</eissn><abstract>Cry1Ab and Cry1Fa toxins are environmentally safe insecticides that control important insect pests.
is an important maize pest that shows low susceptibility to Cry1A toxins, in contrast to Cry1Fa, which is highly active against this pest and is used in transgenic maize for
control. The β16 region from domain III of Cry1Ab has been shown to be involved in interactions with receptors such as alkaline phosphatase (ALP) or aminopeptidase (APN) in different lepidopteran insects. Alanine-scanning mutagenesis of amino acids of Cry1Ab β16 (
STLRVN
) revealed that certain β16 mutations, such as N514A, resulted in increased toxicity of Cry1Ab for
without affecting the toxicity for other lepidopteran larvae, such as
larvae. Exhaustive mutagenesis of N514 was performed, showing that the Cry1Ab N514F, N514H, N514K, N514L, N514Q, and N514S mutations increased the toxicity toward
A corresponding mutation was constructed in Cry1Fa (N507A). Toxicity assays of wild-type and mutant toxins (Cry1Ab, Cry1AbN514A, Cry1AbN514F, Cry1Fa, and Cry1FaN507A) against four
populations from Mexico and one from Brazil revealed that Cry1AbN514A and Cry1FaN507A consistently showed 3- to 18-fold increased toxicity against four of five
populations. In contrast, Cry1AbN514F showed increased toxicity in only two of the
populations analyzed. The mutants Cry1AbN514A and Cry1AbN514F showed greater stability to midgut protease treatment. In addition, binding analysis of the Cry1Ab mutants showed that the increased toxicity correlated with increased binding to brush border membrane vesicles and increased binding affinity for
ALP, APN, and cadherin receptors.
is the main maize pest in South and North America and also is an invasive pest in different African countries. However, it is poorly controlled by
Cry1A toxins expressed in transgenic crops, which effectively control other lepidopteran pests. In contrast, maize expressing Cry1Fa is effective in the control of
, although its effectiveness is being lost due to resistance evolution. Some of the Cry1Ab domain III mutants characterized here show enhanced toxicity for
without loss of toxicity to
Thus, these Cry1Ab mutants could provide useful engineered toxins that, along with other Cry toxins, would be useful for developing transgenic maize expressing stacked proteins for the effective control of
and other lepidopteran pests in the field.</abstract><cop>United States</cop><pub>American Society for Microbiology</pub><pmid>30097439</pmid><doi>10.1128/AEM.01393-18</doi><oa>free_for_read</oa></addata></record> |
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source | American Society for Microbiology; PubMed Central; Alma/SFX Local Collection |
subjects | Alanine Alkaline phosphatase Amino acids Aminopeptidase Bacillus thuringiensis Binding Binding sites Cadherin receptors Cadherins Corn Gram-positive bacteria Insecticides Insects Invertebrate Microbiology Larvae Membrane vesicles Midgut Mutagenesis Mutants Mutation Pest control Pests Populations Proteins Receptors Scanning mutagenesis Spodoptera frugiperda Stability analysis Toxicity Toxins |
title | Enhancement of Bacillus thuringiensis Cry1Ab and Cry1Fa Toxicity to Spodoptera frugiperda by Domain III Mutations Indicates There Are Two Limiting Steps in Toxicity as Defined by Receptor Binding and Protein Stability |
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