Mosquitocidal toxins of spore forming bacteria: recent advancement

Mosquito borne diseases form a major component of vector borne diseases from all over the world. Several control strategies have been adopted to control diseases transmitted by mosquitoes. The discovery of highly potential bacteriocides like Bacillus sphaericus (Bs) and Bacillus thuringiensis subsp. israelensis (Bti) have revolutionized over conventional insecticides in mosquito control programs. The potential genes in Bs for mosquitocidal actions have been cloned and expressed recently. Some mosquito species (Culex pipiens pipiens, C. quinquefasciatus) which had been susceptible to Bs toxin in the field have developed resistance to Bs. But, this was not possible to Bti. The molecular mode of action and mechanism of resistance involved in developing resistance in vector species have been recently explored. The current review paper explores the novelty of these mosquito pathogenic bacteria for the control of disease transmitting mosquitoes. Key Words: Bacillus sphaericus, B. thuringiensis serovar. israelensis, mode of action, binding assays, resistance, management, cost-effective culture media. African Journal of Biotechnology Vol.3(12) 2004: 643-65