You are here: Home
/ Publication Information
Title: Optimization of Cry3A yields in Bacillus thuringiensis by use of sporulation-dependent promoters in combination with the STAB-SD mRNA sequence
Author: Park, Hyun-woo; Ge, Baoxue; Bauer, Leah S.; Federici, Brian A.;
Source: Applied and Environmental Microbiology. 64(10): 3932-3938.
Publication Series: Scientific Journal (JRNL)
Description: The insecticidal activity of Bacillus thuringiensis strains toxic to coleopterous insects is due to Cry3 proteins assembled into small rectangular crystals. Toxin synthesis in these strains is dependent primarily upon a promoter that is active in the stationary phase and a STAB-SD sequence that stabilizes the cry3 transcript-ribosome complex. Here we show that significantly higher yields of Cry3A can be obtained by using dual sporulation-dependent cyt1Aa promoters to drive the expression of cry3Aa when the STAB-SD sequence is included in the construct. The Cry3A yield per unit of culture medium obtained with this expression system was 12.7-fold greater than that produced by DSM 2803, the wild-type strain of B. thuringiensis from which Cry3Aa was originally described, and 1.4-fold greater than that produced by NB176, a mutant of the same strain containing two or three copies of cry3Aa, which is the active ingredient of the commercial product Novodor, used for control of beetle pests. The toxicities of Cry3A produced with this construct or the wild-type strain were similar when assayed against larvae of the cottonwood leaf beetle, Chrysomela scripta. The volume of Cry3A crystals produced with cyt1Aa promoters and the STAB-SD sequence was 1.3-fold that of typical bipyramidal Cry1 crystals toxic to lepidopterous insects. The dual-promoter/STAB-SD system offers an additional method for potentially improving the efficacy of insecticides based on B. thuringiensis.
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
- This publication may be available in hard copy. Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact Sharon Hobrla, email@example.com if you notice any errors which make this publication unusable.
XML: View XML
Park, Hyun-woo; Ge, Baoxue; Bauer, Leah S.; Federici, Brian A. 1998. Optimization of Cry3A yields in Bacillus thuringiensis by use of sporulation-dependent promoters in combination with the STAB-SD mRNA sequence. Applied and Environmental Microbiology. 64(10): 3932-3938.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility