The effectiveness of Pseudomonas pigments as mosquito larvicidal and anti-arbovirus compounds

Understanding ways to control the spread for mosquito born diseases greatly benefits the overall health of society. Because the dengue virus infects about 100 million individuals a year and La Crosse virus infects nearly 100, it would be beneficial to develop safe ways to control the spread of disease by either limiting the transmission of the virus itself or controlling larval populations. Since most methods of controlling mosquito populations involve the widespread distribution of synthetic chemicals which could have negative consequences on the environment, developing new safe ways to accomplish this task will also preserve the welfare of the public. Since it has already been shown that prodigiosin, a pigment produced by Serratia marcescens, has larvicidal properties it would be worth considering other pigments produced by bacteria. The pigments were derived by culturing Pseudomonas aeruginosa (for pyocyanin) and an environmental Pseudomonas isolate (for the prodiginine-like pigment) in specialized media that is required for optimum pigment production. We have shown in preliminary experiments that the Pseudomonas pigments pyocyanin and a likely prodiginine display larvicidal properties when administered to Aedes albopictus and Culex quinquefasciatus mosquito larvae. We have also demonstrated antiviral activity by incubating the pigments with dengue viruses and La Crosse virus, then determining the level of viable virus in cell culture. Successful demonstration of these effects could lead to production of new, environmentally friendly larvicides that may have the added benefit of interfering with arbovirus infection or replication in the mosquito host.