Isolation and identification of the α-protobacteria from Culex pipiens (Diptera. Culicidae) larvae

TRANCHIDA, MARÍA CECILIA; RICCILO, P.; RODRIGUERO, M. S.; GARCÍA, J.J.; MICIELI, M. V.

JOURNAL OF INVERTEBRATE PATHOLOGY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 2012 vol. 109 p. 143 - 147

0022-2011

A survey for pathogens of Culex pipiens larvae was conducted in drainage ditchesin suburban areas of La Plata, Buenos Aires Province, Argentina, from 2003 to 2006. Culex pipiens larvae with white opaque colour were found in several field collections. When the white larvae were dissected and observed in wet mount preparations under a phase contrast microscope, presence of bacteria was recorded. This microorganism was located in the hemocoel. Laboratory experiments were performed to dilucidate the pathway transmission of this pathogen. Traditional culturing approaches have failed to reveal the identity of this new microorganism; however molecular techniques to identify this pathogen were successful. The partial sequence of the 16S rRNA gene provides a powerful tool for the detection of new isolated obtained directly from larval hemocoele of C. pipiens. These bacteria were identified as belonging to the genus Novospirillum. In spite of their wide distribution in different aquatic environments, information related to symbiotic relationship of Novospirillum spp. with aquatic insects is scarce and there have not been described in other mosquito species. This is the first record of Novospirillum spp. as pathogen to mosquito larvae.