Current Microbiology

, Volume 62, Issue 1, pp 38–43 | Cite as

Overproduction of Delta-Endotoxins by Sporeless Bacillus thuringiensis Mutants Obtained by Nitrous Acid Mutagenesis

  • Saoussen Ben Khedher
  • Nabil ZouariEmail author
  • Nadia Messaddeq
  • Patrick Schultz
  • Samir Jaoua


Asporogenic and oligosporogenic Bacillus thuringiensis mutants having the ability to overproduce insecticidal crystal protein were generated by using nitrous acid (50 mg/ml), as chemical mutagenic agent. Insecticidal crystal proteins produced by asporogenic mutants remained encapsulated within the cells. Delta-endotoxin production by most of mutants was improved compared to the corresponding wild strains BNS3 and a mutant M26. The overproduction by asporogenic and oligosporogenic mutants was attributed to defect in genes involved in sporulation and to random mutations affecting cell metabolism at different pathways and delta-endotoxin synthesis. Sporeless bioinsecticides could be developed based on stable and environmentally safe Bacillus thuringiensis mutants.


Shake Flask Complex Medium Glucose Medium Random Mutagenesis Duncan Test 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported by grants from the “Tunisian Ministry of Higher Education, Scientific Research and Technology” and the AUF “Agence Universitaire de la Francophonie”. We wish to thank Pr. Mohamed Ben Khedher and Dr. Moez Feki, for having proofread this paper.

Supplementary material

284_2010_9670_MOESM1_ESM.doc (356 kb)
Supplementary material 1 (DOC 356 kb)


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Saoussen Ben Khedher
    • 1
  • Nabil Zouari
    • 1
    Email author
  • Nadia Messaddeq
    • 2
  • Patrick Schultz
    • 3
  • Samir Jaoua
    • 1
    • 4
  1. 1.Laboratory of BiopesticidesCentre of Biotechnology of SfaxSfaxTunisia
  2. 2.Laboratoire de Microscopie ElectroniqueIGBMCIllkirchFrance
  3. 3.Département de Biologie et Génomique StructuralesIGBMC - UMR7104IllkirchFrance
  4. 4.Biological & Environmental Sciences Department, College of Arts and SciencesQatar UniversityDohaQatar

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