Bacillus thuringiensis: a natural endophytic bacterium found in wild plants

Abstract Despite the fact that Bacillus thuringiensis is the most widely used bacterium in biological pest control, its ecology has been notoriously neglected. Its role in nature is uncertain, and a defined habitat and niche are under discussion. In this report, wild-type strains were isolated from...

Full description

Saved in:
Bibliographic Details
Published in:FEMS microbiology ecology 2023-05, Vol.99 (6)
Main Authors: Espinoza-Vergara, Gabriela, García-Suárez, Rosalina, Verduzco-Rosas, Luis Alfonso, Cando-Narvaez, Areli, Ibarra, Jorge E
Format: Article
Language:English
Subjects:
Bacillus thuringiensis
Bacteria
CRY protein
Endophytes
Gene sequencing
Larvae
Microflora
Morphology
Pest control
Plant species
Plant tissues
Plants (botany)
rRNA 16S
Sterilization
Strains (organisms)
Toxicity
Wildlife
Citations: Items that this one cites
Items that cite this one
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract Despite the fact that Bacillus thuringiensis is the most widely used bacterium in biological pest control, its ecology has been notoriously neglected. Its role in nature is uncertain, and a defined habitat and niche are under discussion. In this report, wild-type strains were isolated from the inner plant tissues as natural endophytic bacteria in wild plants. Once a reliable superficial sterilization technique was standardized, leaf samples from 110 wildlife plant species within 52 families were processed to obtain their endophytic microflora, which were able to grow in artificial media. From 93 morphologically different isolates, 22 showed the typical sporangium morphology of B. thuringiensis (endospore and parasporal bodies). These isolates were identified and characterized by their 16S ribosomal RNA, hag gene, MLST, and cry gene sequences. Also, isolates were characterized by Bc-RepPCR and parasporal body protein content. All the isolates showed at least some of the typical B. thuringiensis features tested, but 10 showed information in all those features, which, in a rigorous selection, were taken as B. thuringiensis sensu stricto strains. Only three subspecies were identified: five kurstaki, four nigeriensis, and one thuringiensis. None showed toxicity against mosquito larvae or Caenorhabditis elegans, and only one showed significant toxicity against Manduca sexta larvae. The role of B. thuringiensis as a natural endophytic bacterium is discussed. From 110 plant species collected in the wild and ornamentals, 12 endophytic Bacillus thuringiensis sensu lato and 10 Bacillus thuringiensis sensu stricto strains were isolated and characterized.
ISSN:1574-6941
0168-6496
1574-6941
DOI:10.1093/femsec/fiad043