NAGIOS: RODERIC FUNCIONANDO

Mutations in the Bacillus thuringiensis Cry1Ca toxin demonstrate the role of domains II and III in specificity towards Spodoptera exigua larvae

Repositori DSpace/Manakin

IMPORTANT: Aquest repositori està en una versió antiga des del 3/12/2023. La nova instal.lació está en https://roderic.uv.es/

Mutations in the Bacillus thuringiensis Cry1Ca toxin demonstrate the role of domains II and III in specificity towards Spodoptera exigua larvae

Mostra el registre parcial de l'element

dc.contributor.author Herrero Sendra, Salvador
dc.contributor.author González Cabrera, Joel
dc.contributor.author Ferré Manzanero, Juan
dc.contributor.author Bakker, Petra L.
dc.contributor.author de Maagd, Ruud A.
dc.date.accessioned 2010-06-29T10:37:21Z
dc.date.available 2010-06-29T10:37:21Z
dc.date.issued 2004
dc.identifier.citation Herrero,S.; González Cabrera, J.; Ferré, J.; Bakker, P.; de Maagd, R.A. Mutations in the Bacillus thuringiensis Cry1Ca toxin demonstrate the role of domains II and III in specificity towards Spodoptera exigua larvae. En Biochemical Journal 384, 2004, 507–513 en
dc.identifier.uri http://hdl.handle.net/10550/13995
dc.description.abstract Several mutants of the Bacillus thuringiensis Cry1Ca toxin affected with regard to specific activity towards Spodoptera exigua were studied. Alanine was used to replace single residues in loops 2 and 3 of domain II (mutant pPB19) and to replace residues 541– 544 in domain III (mutant pPB20). Additionally, a Cry1Ca mutant combining all mutations was constructed (mutant pPB21). Toxicity assays showed a marked decrease in toxicity against S. exigua for all mutants, while they retained their activity against Manduca sexta, confirming the importance of these residues in determining insect specificity. Parameters for binding to the specific receptors in BBMV (brush border membrane vesicles) of S. exigua were determined for all toxins. Compared with Cry1Ca, the affinity of mutant pPB19 was slightly affected (2-fold lower), whereas the affinity of the mutants with an altered domain III (pPB20 and pPB21) was approx. 8-fold lower. Activation of Cry1Ca protoxin by incubation with S. exigua or M. sexta BBMV revealed the transient formation of an oligomeric form of Cry1Ca. The presence of this oligomeric form was tested in the activation of the different Cry1Ca mutants, and we found that those mutated in domain II (pPB19 and pPB21) could not generate the oligomeric form when activated by S. exigua BBMV. In contrast, when oligomerization was tested using BBMV prepared from M. sexta, all of the Cry1Ca mutants showed the formation of a similar oligomeric form as did the wild-type toxin. Our results show how modification of insect specificity can be achieved by manipulation of different parts of the toxin structure involved in different steps of the mode of action of B. thuringiensis toxins. en
dc.language.iso en en
dc.subject Bacterial toxin; Manduca sexta; Mode of action; Protoxin activation; Toxin oligomerization; Toxin receptor binding en
dc.title Mutations in the Bacillus thuringiensis Cry1Ca toxin demonstrate the role of domains II and III in specificity towards Spodoptera exigua larvae en
dc.type journal article es_ES
dc.subject.unesco UNESCO::CIENCIAS DE LA VIDA::Bioquímica en
dc.identifier.idgrec 011258 en
dc.type.hasVersion VoR es_ES
dc.identifier.url http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1134136/pdf/bj3840507.pdf en

Visualització       (313.9Kb)

Aquest element apareix en la col·lecció o col·leccions següent(s)

Mostra el registre parcial de l'element

Cerca a RODERIC

Cerca avançada

Visualitza

Estadístiques