Boonhiang PromdonkoyPatcharee PromdonkoySutipa TanapongpipatPlearnpis LuxananilNamchai ChewawiwatMongkon AudthoSakol PanyimThailand National Center for Genetic Engineering and BiotechnologyMahidol University2018-07-242018-07-242004-01-01Current Microbiology. Vol.49, No.2 (2004), 84-88034386512-s2.0-3242750630https://repository.li.mahidol.ac.th/handle/20.500.14594/21413The mosquitocidal toxin 1 (mtx1) gene from genomic DNA of B. sphaericus strain 2297 was cloned and expressed in E. coli. DNA sequencing analysis of the cloned gene revealed a single open reading frame encoding an 870-amino acid polypeptide. Expression level of the full-length gene in E. coli was very low even though strong promoter was used or the gene was expressed as a fusion protein. Expression level was highly improved after the putative leader sequence was deleted, and the truncated gene was expressed as a fusion protein with glutathione S-transferase (GST-tMtx1). E. coli cells expressing GST-tMtx1 was highly toxic to Culex quinquefasciatus larvae and showed lower toxicity against Anopheles dirus and Aedes aegypti larvae. Enterobacter amnigenus An11, a mosquito larval gut colonizable bacteria, transformed with the cloned gene exhibited mosquito larvicidal activity. Result suggested that there is a potential to develop this protein to be used as an alternative mosquito control agent.Mahidol UniversityImmunology and MicrobiologyArticleSCOPUS10.1007/s00284-004-4274-y