title: Isolation and characterization of halotolerant bacteria associated with the midgut of Culex quinquefasciatus Say (Diptera: Culicidae).
abstract: We show for the first time that the midgut of Culex quinquefasciatus (Say) mosquito larvae harbors halotolerant bacteria. The midgut from field collected Cx. quinquefasciatus larvae were dissected under aseptic conditions, homogenized and plated on LB agar medium with 2% (w/v) NaCl. Two different colonies were successfully isolated and bacterial isolates were identified by 16S rRNA sequences. The halotolerant bacterial isolates were: Halobacillus litoralis (CxH1) and Staphylococcus cohnii (CxH2). The gene sequence of these isolates has been deposited in GenBank (JN016804 and JN183986). These halotolerant bacteria grew in the absence of salt (0%) as well as in the presence of relatively high salt concentrations in culture medium (20%), and grew best in the presence of 8-10% (w/v) NaCl. H. litoralis and S. cohnii showed growth up to 18 and 20% (w/v) NaCl, respectively. Optimum growth temperatures for both the bacteria were between 30-37 degrees C. H. litoralis was resistant to the antibiotics oxacillin, penicillin, polymixin and S. cohnii was resistant to the antibiotic oxacillin.
authors: Entomology Research Institute, Loyola College, Chennai-600 034, Tamil Nadu, India.
authors: Appadurai Daniel
authors: AD
authors: Reegan
authors: Entomology Research Institute, Loyola College, Chennai-600 034, Tamil Nadu, India.
authors: Michael Gabriel
authors: MG
authors: Paulraj
authors: Entomology Research Institute, Loyola College, Chennai-600 034, Tamil Nadu, India.
authors: Savarimuthu
authors: S
authors: Ignacimuthu
mesh_terms: D000818:Animals; D003465:Culex / Q000382:microbiology*; D003470:Culture Media; D004064:Digestive System / Q000378:metabolism / Q000382:microbiology; D058678:Halobacillus / Q000235:genetics / Q000302:isolation & purification*; D007814:Larva / Q000378:metabolism / Q000382:microbiology; D010802:Phylogeny; D013210:Staphylococcus / Q000235:genetics / Q000302:isolation & purification*; D013696:Temperature
chemical_list: D003470:Culture Media