Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Interaction of the Bacillus sphaericusmosquito larvicidal proteins

Davidson, Elizabeth W., Oei, Coreen, Meyer, Marian, Bieber, Allan L., Hindley, John and Berry, Colin ORCID: 1990. Interaction of the Bacillus sphaericusmosquito larvicidal proteins. Canadian Journal of Microbiology 36 (12) , pp. 870-878. 10.1139/m90-151

Full text not available from this repository.


Genes for 51.4- and 41.9-kDa insecticidal proteins of Bacillus sphaericus were separately cloned and expressed in Escherichia coli. Both proteins were required for toxicity. Approximately equal numbers of cells containing the 51.4- and 41.9-kDa proteins produced the greatest toxicity; excess 41.9-kDa protein did not affect toxicity, whereas excess 51.4-kDa protein reduced activity. Larvae were killed when 41.9-kDa protein was fed up to 24 h after the 51.4-kDa protein, but not when the order of feeding was reversed. Radiolabelled toxins bound in approximately equal amounts to the gastric caecum and posterior midgut of Culex quinquefasciatus larvae. Radiolabelled 51.4-kDa protein was rapidly degraded by ca. 12–13 kDa in the larval gut, while 41.9-kDa protein was degraded by 1–2 kDa. Nonreduced toxin extracted from B. sphaericus produced a band on SDS–PAGE of ca. 68–74 kDa that contained both 51.4- and 41.9-kDa proteins based on sequence analysis, and a band of ca. 51 kDa that contained primarily 41.9-kDa protein. Escherichia coli containing 51.4-kDa protein enhanced toxicity of the latter eluted SDS-PAGE band. These proteins may associate very strongly, and trace amounts of 51.4-kDa protein in preparations of 41.9-kDa protein from B. sphaericus may be responsible for the previously reported toxicity of the latter.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Biosciences
Subjects: Q Science > QR Microbiology
Uncontrolled Keywords: Bacillus sphaericus, toxin, mosquito, cloning
Publisher: Canadian Science Publishing
ISSN: 0008-4166
Last Modified: 27 Oct 2022 10:28

Citation Data

Cited 44 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item