title: Recombinant Enterobacter amnigenus highly toxic to Anopheles dirus mosquito larvae.
abstract: The mosquito-larvicidal binary toxin of Bacillus sphaericus 2297 was expressed in Enterobacter amnigenus, a Gram-negative bacterium isolated from Anopheles dirus larvae gut. The toxin was placed under the regulation of various promoters in order to improve the expression level of the toxin. Amongst the recombinants obtained, E. amnigenus harboring pBS373, a plasmid which contains the toxin genes under the control of the native B. sphaericus promoter, expressed a significant amount of protein, comparable to that found in B. sphaericus 2297. In addition, this recombinant provided approximately twenty times higher toxicity against second-instar Anopheles dirus larvae when compared to B. sphaericus 2297. The procedure of obtaining this environmentally isolated bacterium from larvae gut and introducing the system for mosquito-larvicidal toxin synthesis is noteworthy. The promising result presented here provides a substantial degree of confidence for further field studies.
authors.affiliation: National Centre for Genetic Engineering and Biotechnology, Bangkok, 10400, Thailand.
authors.forename: P
authors.initials: P
authors.lastname: Khampang
authors.forename: P
authors.initials: P
authors.lastname: Luxananil
authors.forename: S
authors.initials: S
authors.lastname: Tanapongpipat
authors.forename: W
authors.initials: W
authors.lastname: Chungjatupornchai
authors.forename: S
authors.initials: S
authors.lastname: Panyim
mesh_terms: D000818:Animals; D000852:Anopheles / Q000382:microbiology*; D001407:Bacillus / Q000235:genetics / Q000378:metabolism; D001427:Bacterial Toxins / Q000235:genetics* / Q000378:metabolism* / Q000494:pharmacology; D004754:Enterobacter / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D007422:Intestines / Q000382:microbiology; D007814:Larva / Q000382:microbiology; D010572:Pest Control, Biological; D011995:Recombination, Genetic
chemical_list: D001427:Bacterial Toxins; C046134:binB protein, Bacillus sphaericus